Cell penetrating peptides and compounds comprising cell penetrating peptides for drug delivery

Abstract

Disclosed herein are cell penetrating peptides and compounds comprising cell penetrating peptides for drug delivery.

Description

[0001] Title: Cell penetrating peptides and compounds comprising cell penetratingpeptides for drug deliveryDescription of Invention FIELD OF THE INVENTIONThe present disclosure relates to cell penetrating peptides, compoundscomprising cell penetrating peptides for drug delivery and methods of formingcompounds comprising cell penetrating peptides for drug delivery.BACKGROUND OF THE INVENTION Carcinogenesis is a multi-step process by which normal cells collect metaplastic changes that are usually considered to be an early phase of the disease. Cancer cells are characterized by the ability to sustain proliferative signalling, deregulate cellular energetics, evade growth suppressors, avoid immune destruction, enable replicative immortality, promote inflammation, resist cell death, induce angiogenesis, activate invasion and metastasis. Though, it is well-established that carcinogenesis is largely the result ofirregular activation of oncogenes (for example RAS, ERK or WNT) and / orinactivation of tumor-suppressors (for example APC or p53) which lead tovarious cellular changes, the reasons for carcinogenesis are various or not always known. Furthermore, carcinogenesis pathways involve many genes, factors and conditions, which themselves and their interactions remaincomplicated or unclear. Consequently, there is still a lack of effective anti-cancer medications. Delivery of anticancer agents to specific intracellular locations into cancer cellsin order to cause cellular death is challenging. Active transport of drugs to intracellular targets, via vector molecules such as peptides, requires the development of approaches that can accomplish cellular membranetranslocation. Recently, several approaches including cell penetrating peptides(CPP) have been developed and used to deliver therapeutics with varying degrees of success. A CPP is a class of functional oligopeptide typicallycomprising from 5 to 20 amino acids, often a CPP is positively charged andoften a CPP comprises permeation enhancers. CPPs have the capacity to cross biological membranes in an energy- dependent or energy-independent way and mediate the uptake of single cargos into cells such as nucleic acids, proteins, imaging agents and smallmolecules. They have been experimentally tested in vitro and in vivo, so as toprove the ability to deliver small or large (up to 120 kDA) bioactive cargo inside cells.CPPs have been described and they are used in biomedical applications. Forinstance, CPPs can deliver contrast agents for cell imaging, drugs for therapy, nucleic acids for gene therapy and other molecules. They have been found effective and that is not only because they can easily deliver cargos into cellsbut also because of their adaptability. They are simple to synthesize and tomodify.Despite their advantages, there are no FDA approved CPP-conjugated drugsand several clinical trials have been discontinued. Among the reasons forthese failings are: (1) reduced cell penetration and cellular uptake of the drug due to physicochemical properties of the drug, frequent susceptibility to proteolytic degradation and development of resistance to receptor mediatedentrance; (2) high production cost;to escape from endosomes after being internalized by cells; (4) difficulty indeveloping theragnostics; and, (5) global and unspecific cytotoxicity to healthyand cancer cells (reduced tumor targeting). Although CPPs are able to penetrate cellular membranes, most of them cannot cross the blood-brain barrier (BBB), which is a highly selective semipermeable border of endothelial cells that protects the central nervous system from toxicity. Moreover, a limitation of current CPPs, is the associated difficulty to be equipped simultaneously with different functional moieties in an orthogonal way. One of the main issues of chemotherapeutic approaches in cancer is the selectivity of antitumor agents. Poor drug selectivity might decrease the efficacy and increase the side effects.With a view to mitigating the above problems, the present inventors developednew compounds comprising one or more multi cargo peptides enhanced withCPP abilities. SUMMARY OF THE INVENTION The present invention relates to novel cell penetrating peptides designed as multi-drug carriers to release intracellularly cytotoxic compounds. One nonlimiting example of a CPP according to the present invention is a compoundcomprising the sequence of amino acids of SEQ ID NO: 1 (FRRKRRKRC)connected to leucinamide through the cysteine residue. In this specification,iCPP has the structure: FRRKRRKRC-leucinamide. The sequence of SEQ IDNO: 1 is a polycationic nonapeptide. In iCPP, leucinamide is connected to thenonapeptide of SEQ ID NO: 1 through the cysteine residue. iCPP comprisesarginine and lysine and is capped with hydrophobic phenylalanine andleucinamide, which hydrophobic groups allow for efficient cell penetration withlow toxicity (as has been illustrated through confocal microscopy and flowcytometry (FACS) in the present specification). In the nonapeptide accordingto SEQ ID NO: 1, two lysine (in positions four and seven) and one cysteine (inposition 9) have been incorporated in strategic positions allowing orthogonalconjugation of therapeutic and / or imaging agents that provide for uses as anovel therapeutic, diagnostic or a combination of the two (i.e. a theragnosticcompound). This novel CPP (referred to as iCPP) has been designed tomitigate the problems that are obstacles in developing FDA approved CPP-conjugated drugs.iCPP is a low-cost compound comprising the nonapeptide sequence of SEQID NO: 1, with leucinamide connected to the cysteine residue, that can be synthesized easily and economically via standard peptide synthesis or via MWsynthesis. The full chemical structure of iCPP is as shown in Figure 1.Figure 1: Structure of iCPP (FRRKRRKRC-leucinamide).iCPP can cross the cellular membrane and mediate the uptake of single, ormultiple, cargos into cells such as nucleic acids, proteins, imaging agents andsmall molecules. A major limitation of current CPPs, as mentioned above, is the associated difficulty to be equipped simultaneously with different functional moieties in an orthogonal way. In iCPP, the present inventors strategically placed certain amino acids such as Lysine and Cysteine with the purpose to conjugate one or more moieties. One of the main issues of chemotherapeutic approaches in cancer is the selectivity of antitumor agents. Poor drug selectivity might decrease the efficacy and increase the side effects. One possible way to obtain specificity towards cancer cells is to develop tumor-homing CPPs. In this respect, tumor homing peptides (THP) can be proposed as a solution as they have been developed for triggering a variety of different tumor cells. THPs specifically bind to tumor cells or elements of the tumor microenvironment while they demonstrate no or low affinity to normal cells. Two known and larger categories of vascular-homing peptides are NGR (Asn-Gly-Arg) and RGD (Arg-Gly-Asp); NGR and RGD peptides all containing these tripeptide motifs.The NGR motif was isolated by in vivo phage display in nude mice bearinghuman breast tumors. Different studies have shown that this motif canspecifically bind to the tumor-associated blood vessels expressing CD13 butnot to vessels or epithelia in normal tissues. The NGR peptide is now used as an important drug vehicle that can deliver different cargos such as anticancer drugs and imaging agents for cancer therapy and diagnosis, showing high expressed on the surface of endothelial cells of tumor blood vessels. The NGR peptide-directed vasculature targeting aimed to increase neovasculature- homing attributes. In this regard, a broad spectrum of chemicals have been conjugated synthetically to NGR peptides, including cytotoxic drugs to generate tumour-targeted therapeutics with enhanced efficacy and reduced off-target toxicity, therapeutic proteins, pro-apoptotic peptides, viral particles,imaging agents for in vivo detection of AminoPeptidase N (APN) expression insolid tumours and DNA complexes. Doxorubicin is the first antineoplastic in the anthracycline class coupled to an NGR peptide (CNGRC). RGD (Arg-Gly-Asp) is a known tumor homing peptide class that can serve as a suitable vehicle for glioblastoma cells. It is known that glioblastoma cells express in their surface integrins (eterodimeric transmembrane surface is overexpressed in blood vessels in the tumor, therefore it could be exploited as a pharmacological target to deliver cytokines to tumor blood vessels. The biological target of RGD is av integrins (receptors expressed on cell surface) and they can recognize various av integrins heterodimers expressed in tumor blood vessels, but not in some normal tissues. For those reasons, integrins arementioned for NGR peptide, RGD can be utilized for cancer diagnosis andtherapy by delivering chemotherapeutics, peptides or proteins, nucleic acids, radionuclides, contrast agents in various carcinomas. The characteristics of RGD permit them to be used as homing devices for drugs or other cytotoxic agents to deliver therapy to specific types of cancers in which integrins are over-expressed. The present inventors postulated that iCPP can be tuned to target different tumors through attaching a tumor homing element. In the TumorHoPe database there are 744 different peptides with different tumor homing properties that can be attached to the CPPs of the present invention: i.e. cancer, lung, breast etc. non peptide agents can be also used: hyaluronic acidand biotin. Peptides in this database have been found to target different typesof tumors that include breast, lung, prostate, melanoma, colon and othercancers. These peptides have some common motifs including RGD (Arg-Gly- Asp) and NGR (Asn-Gly-Arg) motifs, which specifically recognize tumor angiogenic markers. Upon tuning the tumor homing element the tumor homingproperties of the carrier are changed, i.e. to target breast, lung, brain or othertypes of cancer. Thus, the CPPs of the present invention can used in personalized therapies. In order to prevent cancer, diagnosis at early stages it is essential through a variety of blood tests and imaging techniques including CT, PET, SPECT, MRIiCPP sequence, such as Lysine and Cysteine, provides regioselectivity byforming amide bonds and disulfide bonds respectively. These kind of reactionsoffer the advantage to load the iCPP simultaneously with THP, cytotoxic drugsand / or contrast agents or fluorescent dyes (DOTA and / or ICG) forming atheragnostic agent (giving therapy and diagnosis). A potential combination of achromophore, drugs and tumor homing element can be in Figure 2.Figure 2: Structure of a compound comprising a novel CPP with multipleconjugation sites. The compounds of the present invention (as depicted generally in Figure 2),which compounds can be referred to as conjugates when conjugated tomultiple different cargos, can have any one, two, three or four of each of:a) Drugs (the CPP can enhance the aqueous solubility of hydrophobicdrugs);b) Imaging agents (fluorescent dyes and / or contrast agents);c) Tumor homing elements; and / or,d) Biomolecules (nucleic acids and / or proteins);attached to the CPP, as shown in Figure 2. Figure 2 shows the possible locations for each component. Some, none or all of these components areincluded in compounds according to the present invention.Representative features of the present invention are set out in the following clauses, which stand alone or may be combined, in any combination, with one or more features disclosed in the text and / or drawings of the specification. Clauses:1. A compound comprising the formula X1-X2-X3-X4-X5-X6-X7-X8-X9-X10-X11-X12(Formula I), wherein: X1is absent or present; when present X1is a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; X2is absent or present; when present X2is an acetyl, a straight chain alkanoyl group, a branched alkanoyl group, a cyclic alkanoyl group, an aminohexanoic acid linker, substituted or unsubstituted C1-C26 alkyl, substituted or unsubstituted C1-C26chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26alkynyl, C1-C26 alkyl substituted with one or more substituted or unsubstituted benzyl groups, or C1-C26alkyl substituted with one or more substituted or unsubstituted triazole groups; X3is phenylalanine (F), alanine (A), valine (V), isoleucine (I), leucine (L), methionine (M), tyrosine (Y), tryptophan (W) or another hydrophobic amino acid group; X4is arginine (R) or D-arginine; X5is arginine (R) or D-arginine; X6is lysine (K), D-lysine, arginine (R), D-arginine, histidine (H), D- histidine or ornithine; optionally, wherein X6is unsubstituted or substituted; when substituted, X6is substituted by a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; X7 is arginine (R) or D-arginine;X8 is arginine (R) or D-arginine;X9is lysine (K), D-lysine, arginine (R), D-arginine, histidine (H), D- histidine or ornithine; optionally, wherein X9is unsubstituted or substituted; when substituted, X9is substituted by a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; X10 is arginine (R) or D-arginine;X11is cysteine (C), a cysteine derivative, D-cysteine, glycine, D-glycine, methionine, D-methionine or penicillamine; optionally, wherein X11is unsubstituted or substituted; when substituted, X11is substituted by a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; and, leucine, D-leucinamide, 2- aminoisobutyric acid or 2-amino-2-methylpropanamide; wherein, X13 is selected from the group consisting of -NH2, -SH2,-SH-W, -OH, -N3, -NH-W, -W or -O-W, wherein W is selected from thegroup consisting of: -CH2CCH, -(CH2)2CCH, -(CH2)3CCH, -(CH2)4CCH, -(CH2)5CCH, -(CH2)6CCH, -CH2N3, -(CH2)2N3, -(CH2)3N3, -(CH2)4N3, - (CH2)5N3, -(CH2)6N3, -CH2OH, -(CH2)2OH, -(CH2)3OH, -(CH2)4OH, - (CH2)5OH or -(CH2)6OH; or a tautomer, polymorph, hydrate, solvate, metabolite, prodrug, formulate or pharmaceutically acceptable salt thereof.2. The compound of clause 1, wherein X1 is absent, X2 is absent, X12 is 3. The compound of clause 1 or clause 2, wherein X4, X5, X7, X8and X10are arginine (R); or, wherein X4, X5, X7, X8and X10are D-arginine (R).4. The compound of any one of clauses 1 to 3, wherein X3 isphenylalanine (F).5. The compound of any one of clauses 1 to 4, wherein X6 and X9 arelysine (K); or, wherein X6and X9are D-lysine (K).6. The compound of any one of clauses 1 to 5, wherein X11 is substitutedor unsubstituted cysteine (C).7. The compound of any one of clauses 1 to 6, wherein X12 is leucine (L),leucinamide, D-leucine or D-leucinamide.8. The compound of any one of clauses 1 to 7, wherein X4, X5, X7, X8 andX10are D-arginine (R) and X12is or 2-amino-2-methylpropanamide.9. The compound of any one of clauses 1 to 7, wherein the compoundcomprises FRRKRRKRC-leucinamide.10. The compound of any one of clauses 1 to 9, wherein one of, two of,three of or four of X1, X6, X9and / or X11are selected from, or substituted with compounds selected from, the group consisting of:

[0002]

[0003] 11. The compound of any one of clauses 1 to 10, wherein X2 is selectedfrom the group consisting of: substituted or unsubstituted C1-C26alkyl, substituted or unsubstituted C1-C26chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26 alkynyl, C1-C26 alkyl substituted with one or more substituted or unsubstituted benzyl groups, C1-C26alkyl substituted with one or more substituted or unsubstituted triazole groups; or, -CH2CH3, -(CH2)2CH3, -(CH2)3CH3, -(CH2)4CH3, -(CH2)5CH3, -(CH2)6CH3, - CH2CH(CH3)2, -(CH2)2CH(CH3)2, -(CH2)3CH(CH3)2or -(CH2)4CH(CH3)2; or, -CH2CH2-, -(CH2)2CH2-, -(CH2)3CH2-, -(CH2)4CH2-, -(CH2)5CH2-, -(CH2)6CH2-, -CH2C(CH3)2-, -(CH2)2C(CH3)2-, -(CH2)3C(CH3)2- or -(CH2)4C(CH3)2-; or,-CH2Cl, -(CH2)2Cl, -(CH2)3Cl, -(CH2)4Cl, -(CH2)5Cl, -(CH2)6Cl, -CH2Br, - (CH2)2Br, -(CH2)3Br, -(CH2)4Br, -(CH2)5Br, -(CH2)6Br, -CH2I, -(CH2)2I, -(CH2)3I, -(CH2)4I, -(CH2)5I or -(CH2)6I; or,-CHCl-, -CHBr- or -CHI-; or,-CH2CCH, -(CH2)2CCH, -(CH2)3CCH, -(CH2)4CCH, -(CH2)5CCH or - (CH2)6CCH; or,-CH2CC-, -(CH2)2CC-, -(CH2)3CC-, -(CH2)4CC-, -(CH2)5CC- or -(CH2)6CC-; or,-CH2N3, -(CH2)2N3, -(CH2)3N3, -(CH2)4N3, -(CH2)5N3or -(CH2)6N3; or, -CHN3-; or, -CH2SH, -(CH2)2SH, -(CH2)3SH, -(CH2)4SH, -(CH2)5SH or -(CH2)6SH; or,-CH2S-, -(CH2)2S-, -(CH2)3S-, -(CH2)4S-, -(CH2)5S- or -(CH2)6S-; or,-CH2COOH, -(CH2)2COOH, -(CH2)3COOH, -(CH2)4COOH, -(CH2)5COOH, - (CH2)6COOH, -CH2COOR2, -(CH2)2COOR2, -(CH2)3COOR2, -(CH2)4COOR2, - (CH2)5COOR2or -(CH2)6COOR2; wherein R2is substituted or unsubstituted C1- C26alkyl; or, -CH2Ar, -(CH2)2Ar, -(CH2)3Ar, -(CH2)4Ar, -(CH2)5Ar, -(CH2)6Ar, -CH2CHArCH3 or -CH2CHArCH2CH3; wherein wherein A1, A2, A3, A4 and A5 are each selected independently but not limited to H, NO2, OH, O-alkyl or O-methyl or substituted or unsubstituted C1-C26 alkyl, substituted or unsubstituted C1-C26 chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26 alkynyl, C1-C26 alkyl substituted with one or more benzyl, pyrrolyl, furanyl, thiophenyl, flavynyl, chromenyl, coumarinoyl, quinolinyl, indonyl, pyridinyl or substituted benzyl, pyrrolyl, furanyl, thiophenyl, flavynyl, chromenyl, coumarinoyl, quinolinyl, indonyl, pyridinyl groups; or, -CH2Tz, -(CH2)2Tz, -(CH2)3Tz, -(CH2)4Tz, -(CH2)5Tz, -(CH2)6Tz, -CH2CHTzCH3 or -CH2CHTzCH2CH3; wherein wherein B is selected but not limited to: substituted or unsubstituted C1-C26alkyl, substituted or unsubstituted C1-C26 chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26alkynyl, C1-C26alkyl substituted with one or more benzyl, pyrrolyl, furanyl, thiophenyl, flavynyl, chromenyl, coumarinoyl, quinolinyl, indonyl, pyridinyl or substituted benzyl, pyrrolyl, furanyl, thiophenyl, flavynyl, chromenyl, coumarinoyl, quinolinyl, indonyl, pyridinyl groups.12. The compound of any one of clauses 1 to 11, wherein X11 is cysteine(C) substituted by a homing peptide, wherein the cysteine residues at X11andin the homing peptide are linked by a -S-S- bond; optionally, wherein thehoming peptide has the sequence CRGDR-COOH (SEQ ID NO: 2).13. The compound of any one of clauses 1 to 12, wherein the drug at eachoccurrence is independently selected from the group consisting of: sunitinib or a derivative of sunitinib (for example SB1), gemcitabine or a derivative of gemcitabine, SN-38 (7-ethyl-10-hydroxycamptothecin) or a derivative of SN- 38, doxorubicin or a derivative of doxorubicin, paclitaxel or a derivative of paclitaxel, temozolomide or a derivative of temozolomide, EMA401 or a derivative of EMA401, camptothecin or a derivative of camptothecin, irinotecan or a derivative of irinotecan, bevacizumab or a derivative of bevacizumab, erlotinib or a derivative of erlotinib.14. The compound of any one of clauses 1 to 13, wherein the fluorophoreat each occurrence is independently selected from the group consisting of: 5(6)-FAM (5(6)-Carboxyfluorescein; IUPAC: 3',6'-dihydroxy-3-oxo- spiro[isobenzofuran-1(3H),9'-[9H]xanthene]-ar-carboxylic acid), Rhodamine B (IUPAC: N-[9-(2-carboxyphenyl)-6-(diethylamino)-3H-xanthen-3-ylidene]-N- ethylethanaminium), IR820 (IUPAC: 2-[2-[2-Chloro-3-[[1,3-dihydro-1,1- dimethyl-3-(4-sulfobutyl)-2H-benzo[e]indol-2-ylidene]-ethylidene]-1- cyclohexen-1-yl]-ethenyl]-1,1-dimethyl-3-(4-sulfobutyl)-1H-benzo[e]indolium hydroxide inner salt, sodium salt), Indocyanine green, Flav7, CH-1055, IR- 1061 (IUPAC: 4-[2-[2-Chloro-3-[(2,6-diphenyl-4H-thiopyran-4- ylidene)ethylidene]-1-cyclohexen-1-yl]ethenyl]-2,6-diphenylthiopyryliumtetrafluoroborate) or IR-1048 (IUPAC: 1-Butyl-2-[2-[3-[(1-butyl-6-chlorobenz[cd]indol-2(1H)-ylidene)ethylidene]-2-chloro-1-cyclohexen-1- yl]ethenyl]-6-chlorobenz[cd]indolium tetrafluoroborate).15. The compound of any one of clauses 1 to 14, wherein X1 is DOTA(IUPAC: 2-[4,7,10-tris(carboxymethyl)-1,4,7,10-tetrazacyclododec-1-yl]acetic acid).16. The compound of any one of clauses 1 to 15, wherein X2 is 6-aminohexanoic acid.17. A conjugate comprising the compound of any one of clauses 1 to 16.18. A conjugate comprising the compound of any one of clauses 1 to 16,wherein the conjugate is of the formula: (conjugate S1ISR1).19. A conjugate comprising the compound of any one of clauses 1 to 16wherein the conjugate is of the formula:

[0004] (conjugate 5(6)-FAM-S1ISR1).20. A pharmaceutical composition comprising a compound according to anyone of clauses 1 to 16, or a conjugate of any one of clauses 17 to 19, and a pharmaceutically acceptable carrier.21. A compound according to any one of claims according to any one ofclauses 1 to 16, or a conjugate of any one of clauses 17 to 19, or a pharmaceutical composition according to clause 20, for use in therapy.22. A compound according to according to any one of clauses 1 to 16, or aconjugate of any one of clauses 17 to 19, or a pharmaceutical composition according to clause 20, for use in treating cancer.23. The compound or pharmaceutical composition for use according toclause 22, wherein the cancer is selected from the group consisting of: breast cancer, ovarian cancer, non-small cell lung cancer, pancreatic cancer and bladder cancer, glioblastoma, acute monocytic leukemia, acute myelogenous leukemia, acute myelomonocytic leukemia, acute promyelocytic leukemia, adult T-cell leukemia, adult T-cell lymphoma, astrocytoma, atypical carcinoid lung cancer, basal cell carcinoma, B-acute lymphocytic leukemia, B-cell acute lymphoblastic leukemia / lymphoma, bladder cancer, brain cancer, and bronchial cancer. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention are described below with reference to the accompanying drawings, in which:Figure 1: Structure of iCPP.Figure 2: Structure of compounds comprising a novel CPP with multipleconjugation sites.Figure 3: Structure of a cell delivery platform comprising a compound ofFormula I.Figure 4: Structure of iCPP derivatized with 6-heptynoic acid.Figure 5: Trimolecular conjugate S1ISR1 (with the sunitinib derivativeand process for its formation.Figure 6: Tetramolecular conjugate 5(6)-FAM-S1ISR1 (with the sunitiniband process for its formation.Figure 7: A) Internalization of 5(6)-FAM-iCPP into HeLa cells. Confocal cell5(6)-FAM-iCPP. Representative fluorescence and bright field images are shown. B) FACs analysis of cellular uptake of 5(6)-FAM- line) compared with analysis of unstained control cells (purple line). Peptide internalization analyzed using the Kolmogorov-Smirnov (KS) statistic test (D- value).Figure 8: The effect of iCPP to A) L-proliferation in 2D proliferation; in 3D culture conditions. Each value represents the means ± SEM from at least three independent experiments.Figure 9: The effect of erlotinib, gefitinib, sunitinib and SB1 in 2 and 3D cellproliferation of glioma cell lines.Figure 10: A) Internalization of 5(6)-FAM-S1ISR1 into HeLa cells. Confocal cell5(6)-FAM-S1ISR1. Representative fluorescence and bright filed images are shown. B) FACS analysis of cellular uptake of 5(6)-FAM- (green line) compared with analysis of unstained control cells (red line). Peptide internalization analyzed using the Kolmogorov-Smirnov (KS) statistic test (D-value).Figure 11: The effect of S1ISR1 in glioma cell lines; U87 (A), LN18 (B & C),and M059K (D & E) 48h after its addition to cells. The results are expressed as % change ± SEM compared to untreated cells from at least three independent experiments. The asterisks denote statistically significant difference between experimental groups and untreated cells. C *P<0,05 and **P<0,001.Figure 12: Comparison of sunitinib, SB1 and S1ISR1 at 100nM in LN18 (A)and M059K (B) cells, 48h after their addition to cells. The results are expressed as % change ± SEM compared to untreated cells from at least three independent experiments. The asterisks denote statistically significant difference between experimental groups and untreated cells. C *P<0,05 and **P<0,001.Figure 13: The effect of sunitinib (appropriate IC50 for each cell line; U87: 29.0migration of U87, LN18 and M059K glioblastoma cells. The images are representative from three different experiments.Figure 14: The effect of sunitinib (appropriate IC50 for each cell line; U87: 29.0cell migration of U87, LN18 and M059K glioblastoma cells. The images are representative from three different experiments.Figure 15: Structure of iCPP-D-Lys (replacement of Fmoc-Lys(Boc)-OH withFmoc-D-Lys(Boc)-OH)Figure 16: Structure of iCPP-D-Arg-D-leucinamide (replacement of Fmoc-Arg(Pbf)-OH with Fmoc-D-Arg(Pbf)-OH and Fmoc-Leu-OH with Fmoc-D-Leu- OH)Figure 17: Structure of iCPP-D-Arg-Aib-NH2 (replacement of Fmoc-Arg(Pbf)-OH with Fmoc-D-Arg(Pbf)-OH and Fmoc-Leu-OH with Fmoc-Aib-OH)Figure 18: Mass spectroscopy for the identification of the iCPP where thefragments determined were: M+3 / 3=474, M+4 / 4=356Figure 19: Mass spectroscopy for the identification of iCPP-D-Lys where wethe fragments determined were: M+3 / 3=474, M+4 / 4=356, M+5 / 5=286Figure 20: Mass spectroscopy for the identification of iCPP-D-Arg-Aib-NH2where the fragments determined were: M+3 / 3=349 Figure 21: Mass spectroscopy for the identification of iCPP-D-Arg-D-leucinamide where the fragments determined were: M+4 / 4=356, M+5 / 5=286.Figure 22. Confocal microscopy of the localization of 5(6)-FAM-iCPP in HeLa cells. Figure 23. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM in after treatment (right). Figure 24. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM Figure 25. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM Figure 26. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM Figure 27. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM Figure 28. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in treatment (right). Figure 29. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in Figure 30. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in Figure 31. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in Figure 32. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in Figure 33. Confocal microscopy of the localization of iCPP-D-Arg-D- leucinamide-5(6)-FAM Figure 34. Confocal microscopy of the localization of iCPP-D-Arg-D- leucinamide-5(6)-FAM Figure 35. Confocal microscopy of the localization of iCPP-D-Arg-D- leucinamide-5(6)-FAM Figure 36. Confocal microscopy of the localization of iCPP-D-Arg-D- leucinamide-5(6)-FAM Figure 37. Confocal microscopy of the localization of iCPP-D-Arg-D- leucinamide-5(6)-FAM after treatment. Figure 38. Mass spectroscopy for the identification of the iCPP-DOTA conjugation where the fragments determined were: M+3 / 3 639.7227, M+4 / 4480.2940, M+5 / 5384.4369 and M+6 / 6 320.5321.Figure 39. Mass spectroscopy for the identification of the D-Lys-iCPP-DOTA conjugation where the fragments determined were: M+4 / 4480.3426 and +5 / 5 384.4712. Figure 40. Mass spectroscopy for the identification of the D-Arg-iCPP-DOTA conjugation where the fragments determined were: M+3 / 3640.1245, M+4 / 4 480.3421 and M+5 / 5384.4367. DETAILED DESCRIPTION OF THE INVENTION The following description and examples illustrate various embodiments of the present disclosure in detail. Those of skill in the art will recognize that thereare numerous variations and modifications of this disclosure that areencompassed by its scope. Accordingly, the description of the disclosedembodiments should not be deemed to limit the scope of the presentdisclosure. Definitions Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art. All patents, applications, published applications and other publications referenced herein are incorporated by reference in their entirety unless stated otherwise. In the event that there is a plurality of definitions for a term herein, those in this section prevail unless stated otherwise. As used herein, any "R" group(s) such as, without limitation, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, and R14 represent substituents that can be attached to the indicated atom. An R group may be substituted orunsubstituted. If two "R" groups are described as being "taken together" the Rgroups and the atoms they are attached to can form a cycloalkyl, cycloalkenyl, aryl, heteroaryl or heterocycle. For example, without limitation, if Raand Rbof an NRaRbgroup are indicated to be "taken together," it means that they are covalently bonded to one another to form a ring: atom(s) to which they are attached to form a ring as an alternative, the R groups may not be limited to the variables or substituents defined previously. comprises a fully saturated (no double or triple bonds) hydrocarbon group. The alkyl group may have 1 to 26 carbon atoms (whenever it appears herein, a e.g.atom, 2 carbon atoms, 3 carbon atoms, 4 carbon atoms, 5 carbon atom, 6carbon atoms, 7 carbon atoms, 8 carbon atoms, 9 carbon atom, 10 carbonatoms, 11 carbon atoms, 12 carbon atoms, 13 carbon atoms, 14 carbonatoms, 15 carbon atoms, 16 carbon atoms, 17 carbon atoms, 18 carbonatoms, 19 carbon atoms, 20 carbon atoms, 21 carbon atoms, 22 carbonatoms, 23 carbon atoms, 24 carbon atoms, 25 carbon atoms or 26 carbonatoms, although the present definition also covers the occurrence of the term umerical range is designated). The alkyl group may also be a medium size alkyl having from 1 to 10 carbon atoms. The alkyl group couldalso be a lower alkyl having from 1 to 6 carbon atoms. The alkyl group of the1-C6 a By1-C6atoms in the alkyl chain, i.e. the alkyl chain is selected from methyl, ethyl,propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, and t-butyl, pentyl (straight and branched) and hexyl (straight and branched). Typical alkyl groups include, but are in no way limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl (straight and branched) and hexyl (straight and branched). Thealkyl group may be mono- or polysubstituted or unsubstituted. Typicalsubstituents can be selected from -OH, -O-C1-6(optionally halo, e.g. F, -Cl, - Br or I)alkyl, -SH, -S-C1-6 alkyl, -N3, -NO2, -halo (e.g. F, -Cl, -Br or I), - COOH, and / or -COOR2(wherein R2is substituted or unsubstituted C1-C26alkyl).triple bonds) mono- or multi-cyclic hydrocarbon ring system. When composedof two or more rings, the rings may be joined together in a fused fashion. Cycloalkyl groups can contain 3 to 10 atoms in the ring(s) or 3 to 8 atoms inthe ring(s). A cycloalkyl group may be unsubstituted or substituted. Typicalcycloalkyl groups include, but are in no way limited to, cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl. Typical substituents can beselected from -OH, -O-C1-6(optionally halo, e.g. F, -Cl, -Br or I)alkyl, -SH, -S-C1-6 alkyl, -N3, -NO2, -halo (e.g. F, -Cl, -Br or I), -COOH, and / or -COOR2 (wherein R2is substituted or unsubstituted C1-C26alkyl). -cyclic or multi- cyclic aromatic ring system (including fused ring systems where two carbocyclic rings share a chemical bond) that has a fully delocalized pi- electron system throughout all the rings. The number of carbon atoms in an aryl group can vary. For example, the aryl group can be a C6-C14 aryl group, a C6-C10aryl group, or a C6aryl group. Examples of aryl groups include, but arenot limited to, phenyl, naphthyl, thienyl, indolyl, benzene, naphthalene andazulene. An aryl group may be mono- or polysubstituted or unsubstituted.Typical substituents can be selected from -OH, -O-C1-6(optionally halo, e.g. F, -Cl, -Br or I)alkyl, -SH, -S-C1-6 alkyl, -N3, -NO2, -halo (e.g. F, -Cl, -Br or I), -COOH, and / or -COOR2 (wherein R2 is substituted or unsubstituted C1-C26 alkyl).containing one or more double bonds. The alkenyl group may have 2 to 20carbon atoms, although the present definition also covers the occurrence of numerical range is designated. The alkenyl group may also be a medium size alkenyl having 2 to 9 carbon atoms. The alkenyl group could also be a lower alkenyl having 2 to 4 carbon atoms. The alkenyl 2-4 alk By way of2-4tomsin the alkenyl chain, i.e. the alkenyl chain is selected from the group consistingof ethenyl, propen-1-yl, propen-2-yl, propen-3-yl, buten-1-yl, buten-2-yl, buten- 3-yl, buten-4-yl, 1-methyl-propen-1-yl, 2-methyl-propen-1-yl, 1-ethyl-ethen-1-yl, 2-methyl-propen-3-yl, buta-1,3-dienyl, buta-1,2,-dienyl, and buta-1,2-dien-4-yl. Typical alkenyl groups include, but are in no way limited to, ethenyl, propenyl,butenyl, pentenyl, and hexenyl, and the like. An alkenyl group may be mono-or polysubstituted or unsubstituted. Typical substituents can be selected from -OH, -O-C1-6 (optionally halo, e.g. F, -Cl, -Br or I)alkyl, -SH, -S-C1-6 alkyl, - N3, -NO2, -halo (e.g. F, -Cl, -Br or I), -COOH, and / or -COOR2(wherein R2is substituted or unsubstituted C1-C26alkyl). As used herein, "Cycloalkenyl" refers to cyclic unsaturated aliphatic hydrocarbyl groups. The numbers of C-atoms referenced in connection with a given cycloalkyl group correspond to the number of rings forming carbon atoms, e.g. "C6 cycloalkenyl" refers to a cyclohexenyl. In some embodiments, the cycloalkenyl comprises one double-bond. In some embodiments, thecyclohexenyl comprises more than one double bond, optionally two doublebonds. containing one or more triple bonds. The alkynyl group may have 2 to 20 carbon atoms, although the present definition also covers the occurrence of numerical range is designated. The alkynyl group may also be a medium size alkynyl having 2 to 9 carbon atoms. The alkynyl group could also be a lower alkynyl having 2 to 4 carbon atoms. The alkynyl 2-4 2-4 tomsin the alkynyl chain, i.e. the alkynyl chain is selected from the group consistingof ethynyl, propyn-1-yl, propyn-2-yl, butyn-1-yl, butyn-3-yl, butyn-4-yl, and 2- butynyl. Typical alkynyl groups include, but are in no way limited to, ethynyl,propynyl, butynyl, pentynyl, and hexynyl, and the like. An alkynyl group may bemono- or polysubstituted or unsubstituted. Typical substituents can beselected from -OH, -O-C1-6(optionally halo, e.g. F, -Cl, -Br or I)alkyl, -SH, -S-C1-6 alkyl, -N3, -NO2, -halo (e.g. F, -Cl, -Br or I), -COOH, and / or -COOR2 (wherein R2 is substituted or unsubstituted C1-C26 alkyl). As used herein, group consisting of a carbon double bonded to an oxygen atom connected with an alkyl or aryl group and an amine group which can be mono or double substituted. As used herein, refers to molecules where a carbon atom is connected to an amino and a carbonyl group along with a side chain whichmay comprise aryl, alkyl, amino, carbonyl, alkoxy, benzyl, guanidine, thiol orthiolethers. Amino acids found in nature include (including their commonabbreviations): Aliphatic amino acids: glycine (Gly, G), alanine (Ala, A), valine (Val, V), leucine (Leu, L), isoleucine (Ile, I) and proline (Pro, P). Polar neutral amino acids: serine (Ser, S) and threonine (Thr, T). Amide containing side chains: asparagine (Asn, N) and glutamine (Gln, Q). Sulfur containing side chains: cysteine (Cys, C) and methionine (Met, M). Aromatic side chains: phenylalanine (Phe, F), tyrosine (Tyr, Y) and tryptophan (Trp, W). Anionic side chains: aspartate (Asp, D) and glutamate (Glu, E). Cationic side chains: histidine (His, H), lysine (Lys, K) and arginine (Arg, R). An amino acid may be in its natural form or it may be a synthetic amino acid. An amino acid may be described as, for example, polar, non-polar, acidic, basic, aromatic or neutral. A polar amino acid is an amino acid that may interact with water by hydrogen bonding at biological or near-neutral pH. The polarity of an amino acid is an indicator of the degree of hydrogen bonding at biological or near-neutral pH. Acidic amino acids have a net negative charge at a neutral pH. Basic amino acids have a net positive charge at a neutral pH. Aromatic amino acids are generally nonpolar, and may participate in hydrophobic interactions. Neutral, aliphatic amino acids are generally nonpolar and hydrophobic. An amino acid may be described by more than one descriptive category. Amino acids sharing a common descriptive category may be substitutable for each other in a peptide. An amino acid residue may be generally represented by a one-letter or three-letter designation, corresponding to the trivial name of the amino acid; see above for example Gfor glycine. Peptides described herein can comprise amino acids in the L- orD- configuration. Amino acids described herein may be modified bymethylation, amidation, acetylation or substitution with other chemical groups which may change the circulating half-life of the peptide without adversely affecting their biological activity. As used herein, - carbon atom alpha to the amino group has the D-configuration. Most amino acids found in nature have the L-configuration. "TEA" refers to triethylamine. "TFA" refers to trifluoroacetic acid. "DMF" refers to N,N-dimethylformamide. "THF" refers to Tetrahydrofuran. "HOBt" refers to 1-Hydroxybenzotriazole. "DIC" refers to N,N-Diisopropylcarbodiimide. "AcOH" refers to acetic acid. "EtOH" refers to ethanol. "DIPEA" refers to N,N-diisopropylethylamine. "rt" refers to room temperature. "h" refers to hour or hours. "mins" refers to minutes. "inert atmosphere" implies the continuous supply of nitrogen gas or argon gas. "Boc-" refers to the protecting group di-tert-butyl decarbonate. an amino acid that is leucine in which the carboxy (- OH) group is replaced by NH2. Unless, stated otherwise, leucinamide refers toL-leucinamide. D-leucinamide refers to the D-configuration of leucinamide.Leucinamide can be abbreviated to Leu-NH2. -proteinogenic amino acid 2-aminoisobutyric acid. -amino-2- -OH)group is replaced by NH2. 2-amino-2-methylpropanamide can be abbreviatedto Aib-NH2. As used herein, characteristics typical of cancer-causing cells, such as uncontrolled proliferation, immortality, metastatic potential, rapid growth and proliferation rate, and certain characteristic morphological features. Cancer cells are often in the form of a tumor, but such cells may exist alone within an animal, or may be a non-tumorigenic cancer cell, such as a leukemia cell. As used herein, the are not limited to, breast cancer, ovarian cancer, non-small cell lung cancer, pancreatic cancer and bladder cancer, glioblastoma, acute monocytic leukemia, acute myelogenous leukemia, acute myelomonocytic leukemia, acute promyelocytic leukemia, adult T-cell leukemia, adult T-cell lymphoma, astrocytoma, atypical carcinoid lung cancer, basal cell carcinoma, B-acute lymphocytic leukemia, B-cell acute lymphoblastic leukemia / lymphoma, bladdercancer, brain cancer, and bronchial cancer.As used herein, "Deregulation" refers to an alteration or modification of the expression of a gene that encodes an enzyme / protein in a biosynthetic pathway, such that the level or activity of said enzyme / protein is altered or modified, which is found in, but is not limited to, cancer cells. As used herein, "Furanyl" comprises a furan ring that can be bound by any carbon atom. As used herein, crystalline form which retains a certain number of water molecules as part of the solid crystalline structure. As used herein, "Overexpression" refers to an excessive expression of a gene, thereby producing an excess of its effect or product. Most cancers arise through the overexpression of key cellular regulatory genes. As used herein, "Pyrrolyl" comprises a pyrrole ring that can be bound by any carbon atom as well as by its nitrogen atom. As used herein, compound that interconvert readily by a chemical reaction called tautomerization, which commonly results in the formal migration of a hydrogen atom or proton, accompanied by a switch of a single bond and adjacent double bond. As used herein, "Thiophenyl" comprises a thiophen ring that can be bound by any C-atom.As used herein, peptide refers to a compound comprising at least two aminoacid residues covalently linked by peptide bonds or modified peptide bonds. However, when specifically used with reference to a specific SEQ ID NO, it is meant to comprise an amino acid sequence such as that represented by thenumbered SEQ ID NO (for example SEQ ID NO: 1). The peptides comprisingamino acids described herein may also be modified either by natural processes, such as posttranslational processing, or by chemical modification techniques which are well known in the art. Modifications can occur anywhere in a peptide, including the peptide backbone, the amino acid side-chains and the amino or carboxyl termini. It is understood that the same type of modification may be present in the same or varying degrees at several sites in a given peptide. does not cause significant irritation to an organism to which it is administered and does not abrogate the biological activity and properties of the compound. In some embodiments, the salt is an acid addition salt of the compound. Pharmaceutical salts can be obtained by reacting a compound with inorganicacids such as hydrohalic acid (e.g. hydrochloric acid or hydrobromic acid),sulfuric acid, nitric acid and phosphoric acid. Pharmaceutical salts can also be obtained by reacting a compound with an organic acid such as aliphatic or aromatic carboxylic or sulfonic acids, for example formic, acetic, succinic, lactic, malic, tartaric, citric, ascorbic, nicotinic, methanesulfonic, ethanesulfonic, p-toluensulfonic, salicylic or naphthalenesulfonic acid. Pharmaceutical salts can also be obtained by reacting a compound with a base to form a salt such as an ammonium salt, an alkali metal salt, such as a sodium or a potassium salt, an alkaline earth metal salt, such as a calcium or a magnesium salt, a salt of organic bases such as dicyclohexylamine, N-methyl- D-glucamine, tris(hydroxymethyl)methylamine, C1-C7alkylamine, cyclohexylamine, triethanolamine, ethylenediamine, and salts with amino acids such as arginine and lysine.It is understood that, in any compound described herein having one or morechiral centers, if an absolute stereochemistry is not expressly indicated, then each center may independently be of R-configuration or S-configuration or a mixture thereof. Thus, the compounds provided herein may be enantiomerically pure, enantiomerically enriched, racemic mixture, diastereomerically pure, diastereomerically enriched, or a stereoisomericmixture. In addition, it is understood that, in any compound described hereinhaving one or more double bond(s) generating geometrical isomers that can be defined as E or Z, each double bond may independently be E or Z a mixture thereof. Where the compounds disclosed herein have at least one chiral center, they may exist as individual enantiomers and diastereomers or as mixtures of such isomers, including racemates. Separation of the individual isomers or selective synthesis of the individual isomers is accomplished by application of various methods which are well known to practitioners in the art. Unless otherwise indicated, all such isomers and mixtures thereof are included in the scope of the compounds disclosed herein. Furthermore, compounds disclosed herein may exist in one or more crystalline or amorphous forms. Unless otherwise indicated, all such forms are included in the scope of the compounds disclosed herein including any polymorphic forms. In addition, some of the compoundsdisclosed herein may form solvates with water (i.e. hydrates) or commonorganic solvents. Unless otherwise indicated, such solvates are included in the scope of the compounds disclosed herein. It is to be understood that where compounds disclosed herein have unfilled valencies, then the valencies are to be filled with hydrogens or isotopesthereof, e.g. hydrogen-1 (protium) and hydrogen-2 (deuterium).It is understood that the compounds described herein can be labelledisotopically. Substitution with isotopes such as deuterium may afford certain therapeutic advantages resulting from greater metabolic stability, such as, forexample, increased in vivo half-life or reduced dosage requirements. Eachchemical element as represented in a compound structure may include anyisotope of said element. For example, in a compound structure a hydrogenatom may be explicitly disclosed or understood to be present in the compound. At any position of the compound that a hydrogen atom may be present, the hydrogen atom can be any isotope of hydrogen, including but not limited to hydrogen-1 (protium) and hydrogen-2 (deuterium). Thus, reference herein to a compound encompasses all potential isotopic forms unless the context clearly dictates otherwise. pharmaceutically acceptable and upon administration is converted to a desired active compound. In some embodiments, the prodrug can be therapeutically inactive until cleaved to release the active compound. The prodrug will contain and a moiety (for example a protecting group) attachedto the active component. Removal of some or all of the moiety will convert the prodrug from an inactive form to an active drug. This is done in the body by a chemical or biological reaction.Depending on the moiety (for example a protecting group) attached to thepharmaceutically active compound, the at least one prodrug formed can be either a neutral (uncharged), a free acid, a free base or a pharmaceutically acceptable anionic or cationic salt form or salt mixtures with any ratio between positive and negative components. These anionic salt forms can include, but are not limited to, for example, acetate, l-aspartate, besylate, bicarbonate, carbonate, d-camsylate, l-camsylate, citrate, edisylate, formate, fumarate, gluconate, hydrobromide / bromide, hydrochloride / chloride, d-lactate, l-lactate, d,l-lactate, d,l-malate, l-malate, mesylate, pamoate, phosphate, succinate, sulfate, bisulfate, d-tartrate, l-tartrate, d,l-tartrate, meso-tartrate, benzoate, gluceptate, d-glucuronate, hybenzate, isethionate, malonate, methylsufate, 2- napsylate, nicotinate, nitrate, orotate, stearate, tosylate, thiocyanate, acefyllinate, aceturate, aminosalicylate, ascorbate, borate, butyrate, camphorate, camphocarbonate, decanoate, hexanoate, cholate, cypionate, dichloroacetate, edentate, ethyl sulfate, furate, fusidate, galactarate (mucate), galacturonate, gallate, gentisate, glutamate, glutamate, glutarate, glycerophosphate, heptanoate (enanthate), hydroxybenzoate, hippurate, phenylpropionate, iodide, xinafoate, lactobionate, laurate, maleate, mandelate, methanesulfonate, myristate, napadisilate, oleate, oxalate, palmitate, picrate, pivalate, propionate, pyrophosphate, salicylate, salicylsulfate, sulfosalicylate, tannate, terephthalate, thiosalicylate, tribrophenate, valerate, valproate, adipate, 4-acetamidobenzoate, camsylate, octanoate, estolate, esylate, glycolate, thiocyanate, or undecylenate. The cationic salt forms can include, but are not limited to, for example, sodium, potassium, calcium, magnesium, zinc, aluminum, lithium, cholinate, lysinium, ammonium, or tromethamine. The term "pharmaceutically acceptable carriers" includes, but is not limited to,0.01-0.1 M and preferably 0.05 M phosphate buffer, or in another embodiment0.8% saline. Additionally, such pharmaceutically acceptable carriers may be in another embodiment aqueous or non-aqueous solutions, suspensions, and emulsions. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such as olive oil, and injectable organic esters such as ethyl oleate. Aqueous carriers include water, alcoholic / aqueous solutions, emulsions or suspensions, including saline and buffered media. In some embodiments, the carrier can be a) 10% PEG (polyethylene glycol) 400 (hydroxypropyl -cyclodextrin), 50% w / v + 60% (v / v) Sterile Water for Injection or b) 0.1% (v / v) Tween 80 + 0.5% (w / v) carboxymethylcellulose in water. The term "subject" refers to a mammal, such as humans, domestic animals, such as feline or canine subjects, farm animals, such as but not limited to bovine, equine, caprine, ovine, and porcine subjects, wild animals (whether in the wild or in a zoological garden), research animals, such as mice, rats, rabbits, goats, sheep, pigs, dogs, and cats, avian species, such as chickens, turkeys, and songbirds. The subject can be, for example, a child, such as an adolescent, or an adult. The term "treatment" refers to any treatment of a pathologic condition in a subject, such as a mammal, particularly a human, and includes: (i) preventing and / or reducing the risk of a pathologic condition from occurring in a subject which may be predisposed to the condition but has not yet been diagnosed with the condition and, accordingly, the treatment constitutes prophylactic treatment for the disease condition; (ii) inhibiting and / or reducing the speed of development of the pathologic condition, e.g., arresting its development; (iii) relieving the pathologic condition, e.g., causing regression of the pathologic condition; or (iv) relieving the conditions mediated by the pathologic conditionand / or symptoms of the pathologic condition. Treatment of subjects who havepreviously and / or are currently, and / or are about to receive a cancer therapy are contemplated herein. The term "therapeutically effective amount" refers to that amount of a compound of the invention that is sufficient to effect treatment, when administered to a subject in need of such treatment. The therapeutically effective amount will vary depending upon the subject and disease condition being treated, the weight and age of the subject, the severity of the disease condition, the manner of administration and the like, which can readily be determined by one of ordinary skill in the art.It is understood that the methods and combinations described herein includecrystalline forms (also known as polymorphs, which include the different crystal packing arrangements of the same elemental composition of a compound), amorphous phases, salts, solvates, and hydrates. In some embodiments, the compounds described herein exist in solvated forms with pharmaceutically acceptable solvents such as water, ethanol, or the like. In other embodiments, the compounds described herein exist in unsolvated form. Solvates contain either stoichiometric or non-stoichiometric amounts of a solvent, and may be formed during the process of crystallization with pharmaceutically acceptable solvents such as water, ethanol, or the like. Hydrates are formed when the solvent is water, or alcoholates are formed when the solvent is alcohol. In addition, the compounds provided herein can exist in unsolvated as well as solvated forms. In general, the solvated forms are considered equivalent to the unsolvated forms for the purposes of the compounds and methods provided herein. Where a range of values is provided, it is understood that the upper and lower limit, and each intervening value between the upper and lower limit of the range is encompassed within the embodiments.CPP StructuresIn some embodiments, the present invention provides the synthesis of a novelCPP referred to as iCPP (FRRKRRKRC-leucinamide). iCPP can beconsidered a vector which can be derivatized with drugs, imaging agents,tumor homing elements, biomolecules and / or other moieties in order to targetspecific cells, such as cancer cells. The present invention also relates to the efficient delivery of different and multiple cargos (dyes, contrast agents, metal chelators, drugs, RNA, DNAand / or plasmids) in the membrane, the cytosol and / or the nucleus of targetcancer cells. The cargo can be covalently bound on the CPP with linkers thatare either labile in the tumor cell microenvironment (for example, disulphide or ester) and / or self-immolative to release the bioactive cargo if necessary orstable bonds (for example, amide or ether) in case the release of the activesubstance is not required.The described compounds and conjugates can be used in diagnosis, tumortreatment, the combination of therapy and diagnosis (theragnostics), genetherapy, bio-imaging and / or as a research tool and a targeting element.In some aspects, the invention relates to multicargo components tuned toeither diagnose and / or treat tumors. These complex compounds have increased stability and are designed to be more potent to escape fromendosomal-lysosomal compartments in order to express the desired actionwhich can be either diagnostic, therapeutic or a combination of them while being less or non toxic to healthy cells. iCPP (FRRKRRKRC-leucinamide) bears positive charged residues (arginines,lysines), a cysteine residue as well as hydrophobic ends (phenylalanine andleucinamide). iCPP has been designed so as to allow a rapid and easy orthogonal conjugation of different combinations of compounds (where thecompounds could be either drugs or fluorescent dyes (chromophores) orbiomolecules or tumor homing element etc. or combinations of them).In some embodiments, the present invention relates to a compoundcomprising the formula X1-X2-X3-X4-X5-X6-X7-X8-X9-X10-X11-X12(Formula I), wherein: X1is absent or present; when present X1is a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; X2is absent or present; when present X2is an acetyl, a straight chainalkanoyl group, a branched alkanoyl group, a cyclic alkanoyl group, anaminohexanoic acid linker, substituted or unsubstituted C1-C26alkyl, substituted or unsubstituted C1-C26 chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26alkynyl, C1-C26 alkyl substituted with one or more substituted or unsubstituted benzyl groups, or C1-C26 alkyl substituted with one or more substituted or unsubstituted triazole groups; X3is phenylalanine (F), alanine (A), valine (V), isoleucine (I), leucine (L), methionine (M), tyrosine (Y), tryptophan (W) or another hydrophobic amino acid group; X4is arginine (R) or D-arginine; X5is arginine (R) or D-arginine; X6is lysine (K), D-lysine, arginine (R), D-arginine, histidine (H), D- histidine or ornithine; optionally, wherein X6is unsubstituted or substituted; when substituted, X6is substituted by a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; X7 is arginine (R) or D-arginine;X8 is arginine (R) or D-arginine;X9is lysine (K), D-lysine, arginine (R), D-arginine, histidine (H), D- histidine or ornithine; optionally, wherein X9is unsubstituted or substituted; when substituted, X9is substituted by a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; X10 is arginine (R) or D-arginine;X11is cysteine (C), a cysteine derivative, D-cysteine, glycine, D-glycine, methionine, D-methionine or penicillamine; optionally, wherein X11is unsubstituted or substituted; when substituted, X11is substituted by a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; and, leucine, D-leucinamide, 2- aminoisobutyric acid or 2-amino-2-methylpropanamide; wherein, X13 is selected from the group consisting of -NH2, -SH2,-SH-W, -OH, -N3, -NH-W, -W or -O-W, wherein W is selected from thegroup consisting of: -CH2CCH, -(CH2)2CCH, -(CH2)3CCH, -(CH2)4CCH, -(CH2)5CCH, -(CH2)6CCH, -CH2N3, -(CH2)2N3, -(CH2)3N3, -(CH2)4N3, - (CH2)5N3, -(CH2)6N3, -CH2OH, -(CH2)2OH, -(CH2)3OH, -(CH2)4OH, - (CH2)5OH or -(CH2)6OH; or a tautomer, polymorph, hydrate, solvate, metabolite, prodrug, formulate or pharmaceutically acceptable salt thereof.A compound comprising Formula I can be used as a novel platform forintracellular multicargo delivery, comprising at least one cell penetrating peptide as described, which in some occasions comprises a covalently linked component at X6or X9and / or peptide or non-peptide construct at X11, which are described above. The delivery platform is capable of delivering cargo by covalent or non-covalent attachment.The cell delivery platform (compound comprising Formula I) may comprisemore than one peptide, more than one component and more than one targeting components coupled to each other in any order without any cargo. The cell delivery platform may be linked to one or more cargoes which may be delivered into cells, tissues or across a cell layer.The invention also relates to novel cell penetrating peptides, compoundscomprising cell penetrating peptides as well as methods of producingmulticargo CPPs. The cell penetrating peptides or compounds comprising cellpenetrating peptides is / are capable of reaching specific cells or tissues ofinterest. The targeting moiety may be an aptamer or targeting peptide such as a homing peptide or a receptor ligand.Figure 3 shows a cell delivery platform where a compound comprising FormulaI is conjugated to another peptide; which other compound can compriseFormula I or which other peptide can have a different structure. The otherpeptide (connected by an -S-S- linker in Figure 3 at X9) can be a targetingcomponent capable of reaching specific cells or tissues, such as a cell or tumor homing peptide, an aptamer, a receptor ligand, a spacer comprising a cleavable site coupled to an inactivating peptide, a peptide ligand, a cytotoxic peptide, a bioactive peptide ligand, a peptide sequence which selectively binds to a certain tissue or cell type or nuclear localization sequence. The otherpeptide (connected by an -S-S- linker in Figure 3 at X9) can be conjugatedtogether with the compound comprising Formula I through lysine, serine orcysteine.One or more spacers may be used to attach the compound comprisingFormula I and the cargoes (when present) to the other peptide (connected byan -S-S- linker in Figure 3 at X9). A spacer may be a linear or branched moietycomprising of one or several lysine, cysteine and / or ornithine residues and / or alkoxy, alkylamino, thioether, alkyl halide, PEGylated chains, disulfide and / or aryl substituted groups. With reference to Figure 3, one or more cargoes may be attached to the delivery system by covalent assembly or complex formation. The cargo maybe a detection marker imaging agent, labelling molecule, a fluorescent marker,aptamer, a receptor ligand, a spacer comprising a cleavable site coupled to an inactivating peptide, a peptide ligand, a cytotoxic peptide, a bioactive peptide,an antibody, a diagnostic agent, a protein or a pharmaceutical (e.g. ananticancer drug, an antiviral and / or antibiotics). Any anticancer drugs used asa cargo may be chosen from, but not limited to, an alkylating agent, a kinaseinhibitor, an antimetabolite and / or a cytotoxic antibiotic.In a further aspect of the invention, the constructs according to the inventionmay be used in the diagnosis of diseases, in the treatment of diseases, thecombination of diagnosis and therapy (theragnostics), in gene therapy, asresearch tools, as targeting systems and / or as pharmaceutical compositions.Materials and Methods Materials for chemical synthesis Unless otherwise stated, reactions were carried out under argon atmosphere, in flame dried, three-neck, with magnetic stirring. Organic solutions wereconcentrated by rotary evaporation at 23 40 °C under 15 Torr. 1H and 13CNMR spectra were measured in CDCl3 or DMSO-d6 on a 250 or 400 MHz Brüker spectrometer.1H chemical shifts are reported in ppm from an internal standard TMS, residual chloroform (7.26 ppm) or DMSO-d6 (2.50 ppm).13C NMR chemical shifts are reported in ppm from an internal standard TMS, residual chloroform (77.00 ppm) or DMSO-d6 (39.43 ppm). High resolution ESI mass spectra were measured on a Bruker EVOQ Elite LC-TQ Systems. Low resolution ESI spectra were measured with an Agilent 1100 LC-MS / MS spectrometer. Analytical thin layer chromatography (TLC) was performed with TLC plates (Merck 70-230 mesh silica gel). TLC visualisation took place under a 254 nm UV light source and by immersion in iodine, ninhydrin solution, acidic aqueous-ethanolic vanillin solution or in basic aqueous potassium permanganate (KMnO4) solution, followed by heating using a heat gun. Purification of reaction products was generally done by dry-column flash Carlo ErbaReactifs-SDS silica gel 60. Solvents, reagents and catalysts were used as received from the manufacturers (Acros, Aldrich, Alfa-Aesar, Fluka and Merk) except for tetrahydrofuran, dichloromethane, ethanol, methanol, ethyl acetate, hexane and toluene that were purified and dried according to recommended procedures. Peptide synthesis of iCPP and RGD -protection either on Rink Amide (iCPP: FRRKRRKRC-leucinamide) or Wang resin (RGD peptide: CRGDR-OH). Amino acids were introduced protected as Fmoc- Cys(Trt)-OH, Fmoc-Arg(Pbf)-OH, Fmoc-Gly-OH, Fmoc-Asp(tBu)-OH, Fmoc- Lys(Boc)-OH (Trt: trityl, Pbf: 2,2,5,7,8-pentamethyl-chromane-6-sulfonyl, tBu: tert-butyl, Boc: tert-Butyloxycarbonyl). Fmoc deprotection steps were carried out by 20 % piperidine in DMF (v / v) for 5-15 min. Coupling reactions of Fmoc amino acids were performed in DMF, using a molar ratio of amino acid / HOBt / DIC / resin (3:3:1). Reactions were monitored by colour Kaiser test. The dry peptide resin was then placed into a rotating reaction vessel and the tested cleavage mixture TFA / EDT / H2O / TIS (94 / 2.5 / 2.5 / 1; v / v / v / v) or TFA / DMB (95 / 5; v / v) was added in a ratio of 20 mL g-1peptide resin. After 3-5 h stirring, the resin was filtered and washed with TFA. The combined filtrates were concentrated under reduced pressure. Hexane was added and the resulting solution was reconcentrated. This procedure was performed twice. The peptide was precipitated with cold diethyl ether, filtered, dissolved in 2N acetic acid, and lyophilized. Synthesis of iCPP derivatised with 6-heptynoic acid iCPP derivatised with 6-heptynoic acid (as shown in Figure 4) was synthesised manually as described before (see peptide synthesis section) on Rink AmideAM resin. 6-heptynoic acid was conjugated to the -NH2 terminal group of thelast amino acid (phenylalanine, F) of iCPP, as a common amino acid. Coupling reaction was performed in DMF using a molar ratio of 6-heptynoic acid / DIC / HOBt / resin (3:3:3:1). The reaction was monitored by colour Kaiser test. The dry peptide resin was then placed into a rotating reaction vessel and the tested cleavage mixture TFA / EDT / H2O / TIS (94 / 2.5 / 2.5 / 1; v / v / v / v) was added in a ratio of 20 mL g-1 peptide resin. After 7 h stirring, the resin was filtered and washed with TFA. The combined filtrates were concentrated under reduced pressure. Hexane was added and the resulting solution was reconcentrated. This procedure was performed twice. The peptide was precipitated with cold diethyl ether, filtered, dissolved in 2N acetic acid, water, acetonitrile and lyophilized.The crude peptide was purified with preparative HPLC. Mobile Phase : A :H2O; B : MeCN; Gradient elution (G1) : linear gradient from A / B 98 / 2 (v / v) to A / B 0 / 100 (v / v) in 30 min. This method showed that it is possible to derivatise iCPP at the X3position, at least when X3is phenylalanine, F. Synthesis of a Sunitinib analogue In order to conjugate a derivative of sunitinib to iCPP, a carboxylic acid analogue of sunitinib was synthesized. The diethylamine moiety in native sunitinib was replaced with a carboxylic acid group where the carbonyl group replaces the interaction of the tertiary amine. The detailed sunitinib synthesis is described below. Synthesis of Sunitinib derivative bearing a carboxylic acid 2-(Hydroxyimino)-3-oxo-butyric acid tert-butyl ester Aqueous sodium nitrite solution (1.74 g, 2 equiv.) was added drop wise to an ice-cooled solution of tert-butyl acetoacetate (2 g, 1 equiv.) in acetic acid (5 ml) keeping the temperature below 15°C. After the addition, the solution was warmed to room temperature and stirred for 1 h. After 2 h, extraction with ether (3 x 25 ml), which was washed with water (10 ml), sodium bicarbonate solution (3 x 10 ml), and water (20 ml), gave 2-(hydroxyimino)-3-oxo-butyric acid tert- butyl ester as a yellow solid (2.1 g, 89%) which was used in next step without further purification. . Ethyl-3-oxobutyrate (1.75 g, 1.2 equiv.) was dissolved in 20 ml of acetic acid, zinc dust (0.557 g, 0.76 equiv.) was added to it and the mixture heated to 60 °C with stirring. The crude 2-(hydroxyimino)-3-oxo-butyric acid tert-butyl ester (2.1 g, 1.0 equiv.) was cautiously added keeping the temperature at about 65 °C by slowing the addition and cooling the flask. More zinc dust (4x 0.557 g, 3.04 equiv.) was added after 1 h in portions and the mixture was stirred at 75- 80°C for 2 h. The mixture was filtered to remove the zinc powder when it was hot, the filtrate was poured on ice and the precipitate was filtered the solid was dissolved in ether (3 x 25 ml), which was washed with water (10 ml), the combined organic extracts were dried with sodium sulphate, filtered and the in vacuo to obtain 2-tert-Butyl 4-ethyl 3,5-dimethyl-1H- as an off white solid (0.615 g) which was used in further purification. MHz, DMSO-d6) : 1.43 (t, J=7.13 Hz, 3H), 1.51 (s, 9H), 2.39 (s,, 4.16 (q, J= 7.13, 14.12 Hz, 2H), 11.62 (s, 1H). MHz, DMSO-d6) : 12.3, 14.1, 14.9, 28.7, 59.4, 80.7, 112.7, 139.4, 160.9, 165.3. : calculated 267.32, found 268.4 1H-pyrrole-3-carboxylic acid ethyl ester 2-tert-Butyl 4-ethyl 3,5-dimethyl-1H-pyrrole-2,4-dicarboxylate 0.61 g wasdissolved in neat trifluoroacetic acid 10 mL and the solution was stirred at room temperature for 30 min (the mix turned Burgundy red with gas evolution), then cooled it to 0 °C on ice bath. Neat trimethylorthoformate 2 mL was added and the mix was stirred at 0 °C for 1 h, the solvent was removed in vacuo the residue was diluted gradually with water addition, the resulting slurry was shaken for 5 min and the precipitated ethyl ester intermediate was collected by filtration, washed thoroughly with water and dried by suction to obtain 5-formyl- 2,4-dimethyl-1H-pyrrole-3-carboxylic acid ethyl ester as a brown solid (0.3 g) which was used in next step without further purification.1H-NMR (400 MHz, DMSO-d6) : 1.27 (t, J=7.08 Hz, 3H), 2.42 (s, 3H), 2.46 (s, 3H), 4.19 (q, J= 7.08, 14.13 Hz, 2H), 9.60 (s, 1H), 12.16 (s, 1H).13C-NMR (100 MHz, DMSO-d6) : 10.4, 13.6, 14.3, 59.1, 112.6, 128.3, 133.8, 142.7, 164.3, 177.9. ESI MS (m / z): calculated 195.22, found 196.1 5-formyl-2,4-dimethyl-1H-pyrrole-3-carboxylic acid 5-formyl-2,4-dimethyl-1H-pyrrole-3-carboxylic acid ethyl ester (0.3 mg) was dissolved in water : methanol (2 ml : 0.5 ml), potassium hydroxide (0.2 g) was added to it and refluxed it for 3 h. It was cooled to room temperature and extracted it with dichloromethane (3 x 5 ml), aqueous layer was acidified to pH 4 with addition of 10 N HCl at 0 °C. The solid was filtered and washed with water (20 ml), dried under reduced pressure to get 5-formyl-2,4-dimethyl-1H- pyrrole-3-carboxylic acid as yellow a solid (0.3 g).1H-NMR (400 MHz, DMSO-d6) : 2.41 (s, 3H), 2.45 (s, 3H), 9.59 (s, 1H), 12.07 (s br, 2H).13C-NMR (63 MHz, DMSO-d6) : 10.4, 13.6, 113.4, 128.2, 134.1, 142.8, 166.0, 177.8. ESI MS (m / z): calculated 167.16, found 168.2 5-fluoro-3-hydrazonoindolin-2-one To a stirred solution of 5-fluoroisatin (2 g, 1 equiv.) in methanol (20 mL) was added dropwise hydrazine hydrate (1.18 mL, 2 equiv.) over a period of 30 min at room temperature. The reaction mixture was heated to refluxing and stirred for 1 h, and then cooled to room temperature and filtered. The solid obtained was washed with methanol and dried in vacuo to give 5-fluoro-3- hydrazonoindolin-2-one as a yellow solid (1.9 g).1H-NMR (250 MHz, DMSO-d6) : 6.82 (dd, J=4.3, 12.03 Hz, 1H), 6.95 (dt, J=1.6, 8.6 Hz, 1H), 7.12 (dd, J=1.7, 8.1 Hz, 1H), 9.74 (d, J=14.5 Hz, 1H), 10.63 (d, J=15.4 Hz, 2H).13C-NMR (100 MHz, DMSO-d6) : 104.5 (dd, J=25.2 Hz), 110.8 (d, J=8.4 Hz), 113.2 (d, J=24.1 Hz), 125.7 (d, J=211.9 Hz), 134.7, 156.8, 159.2, 162.9. ESI MS (m / z): calculated 179.15, found 180.3 5-fluoroindolin-2-one 5-fluoro-3-hydrazonoindolin-2-one (1.9 g, 1 equiv.) was added to a freshly prepared sodium ethoxide (3.6 g, 5 equiv.) in absolute ethanol (20 mL) and heated to refluxing for 5 h, and then cooled to room temperature. To the mixture was added slowly ice-water (50 mL), adjusted to pH 1 with 4 N HCl and filtered. The solid obtained was recrystallized from water to afford 5- fluoroindolin-2-one (1.2 g) as an off-white solid.1H-NMR (400 MHz, DMSO-d6) : 3.48 (s, 2H), 6.78 (dd, J=4.4, 8.4 Hz, 1H), 6.98 (dt, J=2.7, 8.4 Hz, 1H), 7.09 (dd, J=2.4, 6.07 Hz, 1H), 10.35 (s, 1H).13C-NMR (100 MHz, DMSO-d6) : 36.8, 110.2, 112.8, 114.2, 128.3, 140.5, 159.5, 176.8. ESI MS (m / z): calculated 151.14, found 152.2 5-((5-fluoro-2-oxoindolin-3-ylidene)methyl)-2,4-dimethyl-1H-pyrrole-3- carboxylic acid To a solution of 5-formyl-2,4-dimethyl-1H-pyrrole-3-carboxylic acid (0.175 g, 1 equiv.) and 5-fluoroindolin-2-one (0.15 g, 0.95 equiv.) in ethanol (10 mL) pyrrolidine (4 drops) was added and refluxed for 12 h. The reaction mixture was cooled to room temperature and the solid obtained was filtered, washed it with ethanol (20 mL) to obtain 5-((5-fluoro-2-oxoindolin-3-ylidene)methyl)-2,4- dimethyl-1H-pyrrole-3-carboxylic acid as an orange solid (0.26 g).1H-NMR (400 MHz, DMSO-d6) : 2.5 (s, 3H), 2.53 (s, 3H), 6.84 (q, J=3.6 Hz,1H), 6.93 (dt, J=1.3, 8.4 Hz, 1H), 7.74 (s, 1 ),7.77 (d, J=9.9 Hz, 1H), 10.93 (s,1H), 13.85 (s, 1H).13C-NMR (100 MHz, DMSO-d6) : 12.1, 15.1, 106.8, 110.7, 113.4, 116.3, 125.4, 126.7, 127.6, 134.1, 135.3, 141.5, 157.7, 160.1, 166.6, 170.2. ESI MS (m / z): calculated 300.28, found 301.4 Ethyl-3-(5-((5-fluoro-2-oxoindolin-3-ylidene)methyl)-2,4-dimethyl-1H-pyrrole-3- carboxamido) propanoate To a solution of 5-((5-fluoro-2-oxoindolin-3-ylidene)methyl)-2,4-dimethyl-1H- pyrrole-3-carboxylic acid (0.25 g, 1 equiv.) in DMF (5 mL) was added 1-ethyl- 3-(3-dimethylaminopropyl)carbodiimide hydrochloride (0.258 g, 2 equiv.), hydroxybenzotriazole (0.135 g, 1.2 equiv.), triethylamine (0.46 mL, 4 equiv.) -alanine ethyl ester hydrochloride (0.153 g, 1.2 equiv.) and the reaction mixture was stirred at room temperature for 24 h. Brine (200 mL) was added, the solids were collected by vacuum filtration washed with water and dried under vacuum to give ethyl-3-(5-((5-fluoro-2-oxoindolin-3-ylidene)methyl)-2,4- dimethyl-1H-pyrrole-3-carboxamido)propanoate as a yellow solid (0.225 g).1H-NMR (400 MHz, DMSO-d6) : 1.19 (t, J=7.14 Hz, 3H), 2.39 (s, 3H), 2.41 (s, 3H), 2.57 (m, 2H), 3.44 (m, 2H), 4.08 (q, J=7.1, 14.25 Hz, 2H), 6.83 (dd, J=4.5, 8.4 Hz, 1H), 6.92 (dt, J=2.4, 9.4 Hz, 1H), 7.69 (d, 5.6 Hz, 1H), 7.7 (s, 1H), 7.75 (dd, J=2.4, 6.9 Hz, 1H), 10.88 (s, 1H), 13.67 (s, 1H).13C-NMR (100 MHz, DMSO-d6) : 11.1, 13.8, 14.7, 34.7, 35.7, 60.6, 106.5, 110.6, 113.0, 115.2, 121.2, 125.4, 126.4, 127.8, 130.9, 135.1, 137.1, 160.0, 165.4, 170.2, 172.1. ESI MS (m / z): calculated 399.42, found 401.0 3-(5-((5-fluoro-2-oxoindolin-3-ylidene)methyl)-2,4-dimethyl-1H-pyrrole-3- carboxamido) propanoic acid (referred to as SB1) To a solution of ethyl-3-(5-((5-fluoro-2-oxoindolin-3-ylidene)methyl)-2,4- dimethyl-1H-pyrrole-3-carboxamido)propanoate (0.2 g) in methanol (10 mL) 10 ml of 4 N solution of LiOH in H2O was added and stirred at room temperature for 24 h. The mixture was neutralized to pH 7 by adding concentrated HCl and methanol was removed under reduced pressure, the residue was adjusted to pH 3 the solid obtained was filtered washed with water and dried well to obtain 3-(5-((5-fluoro-2-oxoindolin-3-ylidene)methyl)-2,4-dimethyl-1H-pyrrole-3- carboxamido) propanoic acid as a yellow solid (0.155 g).1H NMR (400 MHz, DMSO-d6) : 2.39 (s, 3H), 2.41 (s, 3H), 2.44 (t, J= 1.8 Hz, 2H), 3.44 (m, 2H), 6.85 (dd, J= 4.5 Hz and 8.3 Hz, 1H), 6.94 (td, J= 2.0 Hz and 8.4 Hz, 1H), 7.67 (t, J= 5.4 Hz, 1H), 7.70 (s, 1H), 7.76 (dd, J= 2.0 and 7.0 Hz, 1H), 10.88 (s, 1H), 12.23 (bs, 1H), 13.67 (s, 1H).13C NMR (100 MHz, DMSO-d6) :173.70, 170.18, 165.27, 160.00, 137.19, 135.12, 130.95, 127.72, 126.39, 125.51, 121.24, 115.20, 113.10, 112.86, 110.66, 110.58, 106.67, 106.42, 35.72, 34.68, 13.88, 11.09. HRMS (ESI): m / z calculated C19H19F O4 3: 372.1282, found: 372.1353SB1 and RGD conjugationCRGDR-OH peptide was synthesized manually as described above (peptide synthesis section) on Wang resin. The last Fmoc-cleavage from Cysteine was carried out. A small linker was introduced to conjugate the RGD peptide and sunitinib analogue. Under argon atmosphere, 3 equivalents of bromo-acetic acid, HOBt and DIC were dissolved in 3ml of DMF / DCM 1 / 1 and stirred for 30 min. The mixture was transferred to the reaction vessel containing the NH2- CRGDR-Wang resin peptide, and left stirring overnight. Washes using DMF and DCM were carried out and the reaction was monitored by Kaiser colour test. A slightly orange colour indicates that the reaction was successful.2.5 equivalents of sunitinib and K2CO3 were dissolved in DMF / DCM 1 / 1 and stirred for 30min. The solution was added to the reaction vessel and stirred overnight. Washes using DMF and DCM were carried out until no colourful liquid appeared. The modified peptide resin was dried and cleavage and deprotection was carried out as described under the peptide synthesis section(see Figure 5B for the synthetic method).15 mg of pure iCPP (FRRKRRKRC-leucinamide) and 11.66 mg of DTP reagent (ratio of Cysteine potent sequence to DTP 1 / 5) were used for the formation of 14.4 mg of activated sequence. The whole quantity of DTP reagent was dissolved in 1.5 ml solution of acetic acid and water (3 / 1, v / v) giving pH 3. pH was kept stable during the reaction time by addition of proper solutions (NaOH 0.5 N or HCl 0.5 N). Next, in the reaction vessel the iCPP was added gradually (every 20-30 min) in solid form. The reaction process was monitored by ESI-MS. After 24 h the reaction mixture was lyophilized. Lyophilization was followed by separation of active peptide and the excess of DTP reagent. Separation was performed by extraction in ethyl acetate and water. Thus, separation was achieved by collecting the aqueous phase in which the peptide is dissolved. The ESI-MS of aqueous phase showed that the activated peptide was received in satisfactory purity so as to omit HPLC purification and continue to next step. Lyophilization of the aqueous phase was then preformed and the quantity of 14.4 mg active-iCPP was obtained (89 % yield) (see Figure 5C).Figure 5: (A) Designed trimolecular conjugate S1ISR1 consisting of cellpenetrating peptide (iCPP), a cytotoxic drug (sunitinib derivative, SB1, uin the figure) and integrin targeting element (RGDpeptide). (B,C) Synthetic procedure to obtain the trimolecular S1ISR1 (g). (i) Bromoacetic acid, HOBt, DIC, DMF:DCM 1:1; (ii) K2CO3, DMF:DCM 1:1; (iii) TFA:EDT:H2O:TIS (94:2.5:2.5:1); (iv) DTP, CH3COOH:H2O 3:1; (v) 0,1N CH3COOH. Synthesis of the trimolecular S1ISR1 14.4 mg of active-iCPP and 10.6 mg of pure SB1-CRGDR-OH (1.1 excess) were used for the formation of 21.4 mg of final trimolecular complex. The whole quantity of activated peptide was dissolved in 1 ml acetic acid 0.1 N. SB1-CRGDR-OH was added in the reaction mixture in solid form gradually (every 20-30 min). The reaction was performed in an argon atmosphere with continuous magnetic stirring, and was the reaction was periodically monitored by ESI-MS. After 5 hours the ESI-MS shows no active-iCPP. The reaction mixture was extracted using ethyl acetate. The aqueous phase was lyophilized and 21.4 mg of crude trimolecular S1ISR1 was obtained (yield 93%). Purification of the final product was achieved by RP-HPLC (see Figure 5C). (M+3H)3+= 811.7643 Cell culture and reagentsIn vitro experiments were performed using U87, LN18 and M059Kglioblastoma cell lines, the human cervical cancer-derived HeLa cell line and L-929, a mouse fibroblast cell line. All cell lines were purchased from American Type Culture Collection (ATCC). U87, LN18, M059K and HeLa cells were cultured in DMEM supplemented with 2 mM L-glutamine. The medium for U87, M059K and HeLa cells contained 10 % fetal bovine serum (FBS) (working medium 1 hereafter) and the medium for LN18 contained 5 % FBS (working medium 2 hereafter). L-929 cells were cultured in EMEM supplemented with 2 mM L-glutamine and 10% horse serum (HS). All media were supplemented with 100 U / ml penicillin- 37 °C, 5 % CO2 and 100% humidity. iCPP carrier and S1ISR1 were diluted in water. The tested concentrations for the dose- S1ISR1, they were 0, 10-3, 10-2, 5 x 10-2, 10- other experiments were performed using the IC50 values extrapolated from proliferation curves. MTT assay (2D proliferation assay) To determine whether the tested agents affect cell proliferation, the 3-[4,5- dimethylthiazol-2-yl]-2,5-dimethyltetrazolium bromide (MTT) assay was used. Briefly, cells were seeded at a density of 8 x103cells / well in 48-well plates and treated as described above. Forty-eight hours after addition of agents, MTT solution (5 mg / ml in PBS) was added at a volume equal to 1 / 10, to each well isopropanol (0.33 ml HCl in 100 ml isopropanol) was added to each well in order to solubilize the dark blue formazan crystals. The solution was transferred to 96-well plates and was immediately read in a microplate reader (Tecan, Sunrise, Magellan 2) at a wavelength of 570 nm using reference wavelength 620 nm. Conjugation of iCPP with 5(6)-FAM and cysteine activation 5(6)-FAM-iCPP was synthesized manually as described before (see peptide synthesis section) on Rink Amide AM resin. A 6-aminohexanoic acid was introduced as linker to conjugate 5(6)-FAM and iCPP. Fluorescein was conjugated to the NH2 terminal group of 6-aminohexanoic acid as a common amino acid. Coupling reaction was performed in DMF using a molar ratio of fluorescein / DIC / HOBt / resin (3:3:3:1).5 mg of pure 5(6)-FAM-iCPP (5(6)-FAM- FRRKRRKRC-leucinamide) and 2.86 mg of DTP reagent (ratio of Cysteine potent sequence to DTP 1 / 5) were used for the formation of 5.2 mg of activated sequence. The whole quantity of DTP reagent was dissolved in 1 ml solution of acetic acid and water (3 / 1, v / v) pH 3. pH value was kept stable during reaction time by addition of (NaOH 0.5 N or HCl 0.5 N). Next, in the reaction vessel the potent sequence of 5(6)-FAM-iCPP was added gradually (every 20-30 min) in solid form. The reaction process was monitored by ESI-MS. After 24 h the reaction mixture was lyophilized. Lyophilization was followed by separation of active peptide and the excess of DTP reagent. Separation was performed by extraction in ethyl acetate and water. Thus, separation was achieved by collecting the aqueous phase in which peptide is dissolved. The ESI-MS of aqueous phase showed that the activated peptide was obtained in satisfactory purity and so HPLC purification was not required.3.4 mg of active-5(6)-FAM- iCPP were obtained (64 % yield) (see Figure 6B-C). Synthesis of tetramolecular 5(6)-FAM-S1ISR1 The active-5(6)-FAM -iCPP (3.4 mg) and pure Sunitinib-CRGDR-OH (1.1 equivalence) (2 mg) were used for the formation of 8 mg of final tetramolecular complex. The entire quantity of activated sequence was dissolved in 1 ml acetic acid 0.1 N. Sunitinib-CRGDR-OH was added in the reaction mixture in solid form gradually (every 20-30 min). The reaction was performed in argonatmosphere and continuous magnetic stirring, while being periodicallymonitored by ESI-MS. After 5 h the ESI-MS shows no active-5(6)-FAM-iCPP. The reaction mixture was extracted using ethyl acetate. The aqueous phase was lyophilized and 7 mg of crude tetramolecular-complex were obtained (yield 87 %). Purification of the final product was achieved by RP-HPLC (see Figure 6D). Figure 6: (A) Designed tetramolecular 5(6)-FAM-S1ISR1 consisting of cell penetrating peptide (iCPP), a cytotoxic drug (sunitinib derivative, SB1), an integrin targeting element (RGD peptide) and carboxyl fluorescein. (B,C) Synthetic procedure to obtain the tetramolecular 5(6)-FAM-S1ISR1 (m). (i) 6- aminohexanoic acid, HOBt, DIC, DMF:DCM 1:1; (ii) 20% piperidine in DMF (v / v) ; (iii) 5(6)-FAM, HOBt, DIC, DMF:DCM 1:1; (iv) TFA:EDT:H2O:TIS (94:2.5:2.5:1); (v) DTP, CH3COOH:H2O 3:1; (vi) 0,1N CH3COOH. Imaging of cells by confocal microscopy HeLa cells were plated on coverslips in 24 well plates (5x104 cells / well) for 24 h. The next day, after complete adhesion the culture medium was exchanged (dissolved in Phosphate-buffered saline, PBS) in medium without serum. Cells were washed five times with cold PBS and the coverslips placed on preheatedaluminium slides for live cell microscopy. Distribution of fluorescently labelledpeptides was analyzed using a Leica TCS SP5 confocal microscope (Leica Microsystems GmbH, Mannheim, Germany) objective HCX PL APO CS 63.0x1.4 oil UV.5(6)-FAM-labeled peptides were excited at 488 nm using an argon laser and their emission was detected at 500-600 nm. Flow cytometry To analyze the internalization of peptides by FACS, HeLa cells were plated into 12 well tissue culture plates (12 x 104 cells / well) for 24 h. The next day, after complete adhesion the culture medium was exchanged and replaced with peptides in medium without serum for 1hr at 37 °C. After this incubation, the cells washed three times with PBS, were then treated with 0.05% Trypsin (500 were centrifuged at 1,300 rpm for 5 min and after the supernatant was removed, were resuspended in PBS. The samples were subjected on a FACS calibur (BD Biosciences) flow cytometer using 488 nm laser excitation and a 525 nm emission filter. For negative control they used unstained HeLa cells -FITC antibody (ImmunoTools). Cell colony formation (3D proliferation assay) U87, LN18 and M059K were cultured in soft agar assay using a standard procedure. Briefly, in a 12-well plate, a bottom layer consisting of 0.7 % agar in 1ml working medium 1 or 2 according to cell line was first allowed to solidify in each well. Appropriate number of cells (5 x 104 cells / well) mixed with 1 ml working medium 1 or 2 that contains 0.5 % agar and it was allowed to solidify on the top of the bottom agar media layer. Each well was further supplemented with 1 ml fresh working medium 1 or 2 once a week with or without the tested agents at the concentration of IC50. After 10-15 days of incubation at 37 °C, 5 % CO2 and 100 % humidity, cells were stained with crystal violet 0.05 % and visualized in an inverted microscope (Axiovert 40 CFL, AxioCam ERc, Zeiss, Germany) at a magnitude of 4X or 10X. Boyden chamber assay (Single cell migration) To evaluate the effect of trimolecular S1ISR1 on single cell migration, a Biosciences, Oxford, UK) was used. Cells were cultured with working medium 1 or 2, after reaching 100% of confluence, were trypsinized and resuspended at 3 x 104 / 0.1ml in medium with 1% FBS. Cell solution was loaded in the upper chamber. The bottom chamber was filled with 0.6 ml of working medium 1 or 2. Twenty-four hrs later, the non-invading cells were removed from the upper compartment using a cotton swab. Transwell filters were fixed with saline-buffered formalin for 10 min and then in 100% methanol for 20 min. Cells were stained in toluidine blue solution for 10 min and washed twice in 1% PBS. Images of cells that have migrated through the filter were captured using an inverted microscope (Axiovert 40 CFL, AxioCam ERc, Zeiss, Germany) at a magnification of 20X. Scratch-wound assay (Collective cell migration) The effect of Sunitinib and S1ISR1 on collective cell migration was evaluated using 2D scratch-wound assay. Cells were seeded in 6-well plates at a density of 2.5 x105 cells / well. After reaching 100% confluence, an artificial gap was created by a yellow pipette tip. Cells were then rinsed several times with the appropriate medium to remove dislodged cells. In order to prevent the effect of cell expansion proliferation on cell movement, cells were treated with cytosineß-D- -Aldrich Chemie GmbH,Germany), a selective inhibitor of DNA synthesis but not of RNA synthesis for 1 h. The medium was replaced, S1ISR1 was finally added to cells and 24 h later images of living cells were captured using an inverted microscope at 4X magnification (Axiovert 40 CFL, AxioCamERc, Zeiss, Germany). Statistical Analysis Differences between groups and controls were tested by one-way ANOVA (OriginPro 8 SR0, Northampton, USA). Each experiment included at least triplicate measurements. All results are expressed as mean ± SEM from at least three independent experiments. In case of peptide internalization the analysis was performed using the Kolmogorov-Smirnov (KS) statistic test (D- value). Results and Discussion Design, synthesis and purification of a trimolecular conjugate consisted of a novel cell penetrating peptide a tumor targeting element and a cytotoxic drug Sunitinib (SU11248, Pfizer) which exhibits potent antitumor activity is an oral, small-molecule, multi-targeted receptor tyrosine kinase (RTK) inhibitor. It has been approved for the treatment of metastatic renal cell carcinoma (mRCC) and imatinib-resistant gastrointestinal stromal tumor (GIST). Although there are reports over the insufficient activity of sunitinib in glioblastoma, only a few report the activity of analogues of sunitinib in glioblastoma. In order to generate a tumor homing peptide for selective targeting, a carboxylic acid containing analogue of sunitinib was synthesized. The diethylamine moiety in native sunitinib was replaced with a carboxylic acid group where the carbonyl group replaces the interaction of the tertiary amine group. The increased efficiency of drug is achieved when it is specifically toxic for the tumor cells and remains nontoxic for the healthy cells. This is hard to achieve unless the drug is guided selectively to the tumor cells. According to the data presented below, the carrier iCPP showed its selectivity towards the tumor cells over normal cells and therefore coupling it to the drug may v 3 integrins are reported to be overexpressed in several cancer cells such as breast, melanoma, ovarian cancer, prostate and glioblastoma. On the other side the RGD peptides are reported to have v 3 integrins, the attachment of the drug on the RGD would enhance tumor targeting capability. The trimolecular compound (g) (Figure 5) was synthesized consisted of the drug, the cell penetrating peptide, and the tumor homing peptide (RGD peptide) and their activity is compared. The attachment of fluorescent label to track the path of the trimolecular complex would conclude also the track of the drug, so the tetramolecular complex is synthesised where the label is conjugated to the trimolecular via an amide linkage. Conjugation of the dye to the trimolecular molecule enables its potential to be used as a theragnostic device. Internalization analysis by confocal microscopy and FACSInitially, 5(6)-FAM was conjugated to iCPP and its ability to enter into cells wasstudied. First localization of 5(6)-FAM-iCPP in HeLa cells was studied, 1 h after its addition to serum free medium and found the iCPP in the cytoplasm asshown in Figure 7A. In order to quantify its cellular uptake, a FACS analysiswas performed and it was found that 5(6)-FAM-iCPP was quantitatively incorporated by cells as confirmed by the analysis based on D value (D=0.92, p=0.001). A similar analysis based on confocal microscopy and FACS was conducted for the trimolecular (S1ISR1) conjugated with 5(6)-FAM (5(6)-FAM-S1ISR1). The same analysis based on D value revealed the quantitative cell uptake of S1ISR1 by HeLa cells (D=1.00, p=0.001).Figure 7: A) Internalization of 5(6)-FAM-iCPP into HeLa cells. Confocal cell5(6)-FAM-iCPP. Representative fluorescence and bright field images are shown. B) FACs analysis of cellular uptake of 5(6)-FAM- line) compared with analysis of unstained control cells (purple line). Peptide internalization analyzed using the Kolmogorov-Smirnov (KS) statistic test (D- value).In vitro cytotoxicityCell culture and reagents U87, LN18 and M059K were treated with erlotinib, gefitinib and sunitinib. All drugs were diluted in DMSO and their final concentration in culture medium was less than 0.5%. Erlotinib, gefitinib and sunitinib were used at 0, 1, 2, 5, 10, Apoptosis assay Cells were plated at 3 x 104cells / well in 24-well plates. iCPP carrier was added to cells at the indicated concentration. At the end of the 48 h incubation, cells were washed twice with PBS, trypsinized for 7 min and centrifuged for 4 min at 166 g. Apoptotic and necrotic cells were detected using the Muse - Millipore, Germany). Briefly, cells were resuspended in medium with 1% FBSand 100 l from cell suspension was incubated with 100 l of Muse AnnexinV & Dead Cell reagent for 20 min, protected from light at room temperatureAfter the incubation, cells were analysed by Muse Cell Analyzer, accordingsoftware, Merck-Millipore, Germany). The assay application using annexin V (An) and a dead cell marker (DCM) distinguishes 4 populations; the viable (An- / DCM-), the early apoptotic (An+ / DCM-), the late apoptotic (An+ / DCM+) and the necrotic (An- / DCM+) cells. The sum of early and late apoptotic cells calculated as apoptotic cells. Cell cycle analysis Cells were plated at 1 x 106cells per Petri dish and iCPP carrier was added at the indicated concentration. At the end of the 48 h incubation, cells were washed twice with PBS, trypsinized for 7 min and centrifuged for 4 min at 166g. Cell cycle analysis was performed using the Muse Cell Cycle kit-Millipore, Germany). Briefly, cells were washed once with phosphate buffer saline (PBS) and centrifuged for 5 min at 300 g. The supernatants were discarded leaving approximately 50 added drop-wise into a tube containing 1 ml of ice cold 70% ethanol while vortexing at medium speed. The samples were kept at -20 C for at least 3 h.was resuspended in 200 l of Muse Cell Cycle Reagent and cells wereincubated for 30 min, protected from light, at room temperature. After theincubation, cells were analysed by Muse Cell Analyzer, according to thesoftware, Merck-Millipore, Germany). The potential toxicity of iCPP in the non-cancerous cells, L-929 (mouse fibroblasts) cells number was examined and no cytotoxicity was found 48 h after its application to cells. The IC50 value, extrapolated from the dose in figure 8A. The evidencewas confirmed from cell proliferation curve by studying types of cell death No effect was found of iCPP in L-929 apoptosis, necrosis and cell cycle arrest as shown in table 1. Table 1: The effect of iCPP in L-929 cell apoptosis, necrosis and cell cycle arrest. Its effect in glioblastoma cells was further investigated; U87, LN18 and M059K.It was found that iCPP decreased cell number in a dose dependent manner 48for U87, LN18 and M059K cells, respectively, as shown in figure 4B. Also, the effect of iCPP in 3D cell cultures of glioblastomas was studied at the concentration of IC50 values for each cell line and an inhibitory effect was found in cell colony formation as shown in figure 8C. The effect of iCPP was studied in different types of cell death including apoptosis, necrosis and cell cycle arrest. The experiments were performed using the IC50 values. It was found that the effect of iCPP carrier in M059K cells was in line with an increase in cell apoptosis with statistically significant manner (p=0,005) as shown in table 2. However, in case of U87 and LN18 cells there was no effect in apoptosis, necrosis or cell cycle arrest at G0 / G1 phase (table 2). It is possibleto assume that in these cells another type of death might occur like autophagy, a type of death related to endocytosis or anoikis, a form of programmed cell death that occurs in anchorage-dependent cells when they detach from the surrounding extracellular matrix (ECM). Table 2: The effect of iCPP in cell death of U87, LN18 and M059K Figure 8: The effect of iCPP to A) L-proliferation; in 3D culture conditions. Each value represents the means ± SEM from at least three independent experiments. iCPP, was conjugated with a molecule containing modified sunitinib (SB1), with the following structure: (SB1). sunitinib modified sunitinib (SB1)The sunitinib derivative was chosen to be modified according to its effect in glioma cells compared to erlotinib and gefitinib. The latter drugs target solely EGFR and sunitinib targets PDGFR, VEGFR, RET, CSF-1R and flt3. Sunitinib exerted an improved effect in 2D and 3D cell proliferation as shown in figure 9A, B, C and D. The IC50 values are shown in table 3 as were extrapolated by proliferation curves. The superior effect of sunitinib was confirmed by the results from cell apoptosis, necrosis and cycle arrest as shown in table 4. The antitumor effect of sunitinib was in line with apoptosis increase. A similar effectwas observed with SB1, too. Figure 9: The effect of erlotinib, gefitinib, sunitinib and SB1 in 2 and 3D cell proliferation of glioma cell lines. The dose response curves of erlotinib(A), gefitinib(B), sunitinib (C)and SB1 (D) in U87, LN18 and M059K cell lines were their effect in 3D cultures of the same cell lines (E) using the IC50 values for 2 wks period treatment. The results are representative from three independent experiments. Table 3: The IC50values for erlotinib, gefitinib, sunitinib and SB1 as were extrapolated by dose response curves Table 4: The effect of erlotinib, gefitinib and sunitinib in cell death Figure 10: A) Internalization of 5(6)-FAM-S1ISR1 into HeLa cells. Confocal cell5(6)-FAM-S1ISR1. Representative fluorescence and bright filed images are shown. B) FACS analysis of cellular uptake of 5(6)-FAM- (green line) compared with analysis of unstained control cells (red line). Peptide internalization analysed using the Kolmogorov-Smirnov (KS) statistictest (D-value). After the synthesis of the molecule S1ISR1, dose response experiments were performed -3, 10- 2, 5x10-2, 10x10- entity was estimated 48 h after its application to glioma cells as shown in figure 11. Although it was found that S1ISR1 had no effect in U87 glioma cell proliferation (fig.11A), S1ISR1 exerted an antiproliferative effect in LN18 and M059K cells (fig.11B & D) consistent with a U-shaped dose response curve as shown in figure 11C and E. The figures since that concentration was toxic for cells. The dose of S1ISR1 with the highest inhibitory effect was 100 nM. This is not the first time that an agent does not demonstrate the typical sigmoidal dose response curve. Previous reports show that several antitumors agents have a similar profile. The concentration was compared of S1ISR1 with 100 nM of sunitinib and 100 nM of SB1. SB1 at this concentration presented no cytotoxicity with respect to native sunitinib. However, upon conjugation of SB1 to the iCPP carrier and the tumor homing peptide (RGD) forming the trimolecular compound S1ISR1 in the very same concentration the trimolecular compound presented a superioreffect than native sunitinib and SB1 as shown in figure 12. This result furtherclarifies the applicability of our strategy to amplify the cytotoxicity of anticancer drugs through their incorporation on the iCPP-RGD carrier system. Figure 11: The effect of S1ISR1 in glioma cell lines; U87 (A), LN18 (B & C),and M059K (D & E) 48h after its addition to cells. The results are expressed as% change ± SEM compared to untreated cells from at least three independent experiments. The asterisks denote statistically significant difference between experimental groups and untreated cells. C *P<0,05 and **P<0,001.Figure 12: The comparison of sunitinib, SB1 and S1ISR1 at 100nM in LN18(A) and M059K (B) cells, 48h after their addition to cells. The results are expressed as % change ± SEM compared to untreated cells from at least three independent experiments. The asterisks denote statistically significant difference between experimental groups and untreated cells. C *P<0,05 and **P<0,001. Furthermore, the effect of S1ISR1 was tested on single and collective cell migration of glioblastoma cells. S1ISR1 inhibited both types of cell migration in U87, LN18 and M059K cells as shown in figure 13 and 14. It is noteworthy that proliferation. In case of U87 and M059K cells, the effect of S1ISR1 was superior to sunitinib in both single and collective migration. In LN18 cells, a superior effect was observed in single cell migration (Fig.13), while in collective cell migration the effect of S1ISR1 and sunitinib was similar (Fig. 14).Figure 13: The effect of sunitinib (appropriate IC50 for each cell line; U87: 29.0migration of U87, LN18 and M059K glioblastoma cells. The images are representative from three different experiments.Figure 14: The effect of sunitinib (appropriate IC50 for each cell line; U87: 29.0cell migration of U87, LN18 and M059K glioblastoma cells. The images are representative from three different experiments.iCPP derivatives were synthesised, so as to test changes in stability and / orimprovements the physicochemical profile of the iCPP.Peptide synthesis of iCPP-D-Lys, iCPP-D-Arg-Aib-NH2, iCPP-D-Arg-D-leucinamide iCPP was modified by replacing certain amino acids with their respective D-amino acids. The respective peptides were then conjugated to 5(6)-FAM andthe resulting conjugates tested in cells by confocal microscopy. -protection onRink Amide AM resin. Amino acids were introduced protected as Fmoc-Cys(Trt)-OH, Fmoc-Arg(Pbf)-OH, Fmoc-Gly-OH, Fmoc-Phe-OH, Fmoc-Aib-OH, Fmoc-Asp(tBu)-OH, Fmoc-Lys(Boc)-OH, Fmoc-D-Arg(Pbf)-OH, Fmoc-D-Lys(Boc)-OH, Fmoc-D-Leu-OH (Trt: trityl, Pbf: 2,2,5,7,8-pentamethyl-chromane-6-sulfonyl, tBu: tert-butyl, Boc: tert-Butyloxycarbonyl). Fmoc deprotection steps were carried out by 20% piperidine in DMF (v / v) for 5 and 15 min. Coupling reactions of Fmoc amino acids were performed in DMF, using a molar ratio of amino acid / HOBt / DIC / resin (3:3:3:1). Reactions were monitored by colour Kaiser test. The dry peptide resin was then placed into a rotating reaction vessel and the tested cleavage mixture TFA / EDT / H2O / TIS(94 / 2.5 / 2.5 / 1; v / v / v / v) was added in a ratio of 20 mL g-1 peptide resin. After 7 hstirring, the resin was filtered and washed with TFA. The combined filtrates were concentrated under reduced pressure. Hexane was added and the resulting solution was reconcentrated. This procedure was performed twice. The peptide was precipitated with cold diethyl ether, filtered, dissolved in 2Nacetic acid, water, ACN and lyophilized.To test the cell penetrating ability of the peptides they were conjugated with5(6)-FAM as described above correspondingly with iCPP.5(6)-FAM-iCPP peptides were synthesized manually as described before (see peptide synthesis section) on Rink Amide AM resin. Fluorescein was conjugated to the NH2 terminal group of the last amino-acid in each peptide, as a common amino acid. Coupling reaction was performed in DMF using a molar ratio of fluorescein / DIC / HOBt / resin (3:3:3:1).Figure 15: Structure of iCPP-D-Lys (replacement of Fmoc-Lys(Boc)-OH withFmoc-D-Lys(Boc)-OH)Figure 16: Structure of iCPP-D-Arg-D-leucinamide (replacement of Fmoc-Arg(Pbf)-OH with Fmoc-D-Arg(Pbf)-OH and Fmoc-Leu-OH with Fmoc-D-Leu- OH)Figure 17: Structure of iCPP-D-Arg-Aib-NH2 (replacement of Fmoc-Arg(Pbf)-OH with Fmoc-D-Arg(Pbf)-OH and Fmoc-Leu-OH with Fmoc-Aib-OH)Figure 18: Mass spectroscopy for the identification of iCPP (SEQ ID NO: 1)where the fragments determined were: M+3 / 3=474, M+4 / 4=356Figure 19: Mass spectroscopy for the identification of iCPP-D-Lys where thefragments determined were: M+3 / 3=474, M+4 / 4=356, M+5 / 5=286Figure 20: Mass spectroscopy for the identification of iCPP-D-Arg-Aib-NH2where the fragments determined were: M+3 / 3=349Figure 21: Mass spectroscopy for the identification of iCPP-D-Arg-D-leucinamide where the fragments determined were: M+4 / 4=356, M+5 / 5=286.Cell culture HeLa cells were cultured in DMEM (Sigma, low glucose), supplemented with 10% FBS and 1% Penicillin / Streptomycin. Cells were incubated at 37oC and 5% CO2 in a humidified atmosphere. Confocal Microscopy HeLa cells were plated on coverslips in 24-well plates (50000 cells / well). The next day cells were incubated with 10 of peptides (diluted in DMSO) for 30. Then, they were washed with PBS buffer (1X) and fixed with 3.7% PFA for 15 min. The cells were again washed with PBS and quenched with 50 mM NH4Cl for another 15 min. Finally, coverslips were mounted on glass slides with a drop of Mowiol containing DABCO. Samples were analyzed by monitoring the fluorescence of peptides using a Leica TCS-SP5 confocal microscope.Peptides were excited at 488 nm using the Argon laser. The peptides thatwere tested were iCPP-D-Arg-Aib-NH2, iCPP-D-Lys iCPP-D-Arg-D-leucinamide 5,6-carboxy fluorescein (5(6)-FAM). The localization of 5(6)-FAM-iCPP in HeLa cells was studied 1 h after its addition to serum free medium and found the iCPP in the cytoplasm. Figure 22. Confocal microscopy of the localization of 5(6)-FAM-iCPP in HeLa cells.Then localization of different iCPP derivatives conjugated with 5(6)-FAM wasstudied, so as to compare their cell penetrating ability with iCPP of Figure 1(SEQ ID NO: 1). It was observed that all the derivatives seem to have exceptfrom cytoplasm internalization, nucleus internalization too. Further studies of nucleus staining and confocal experiments were carried out again and FACSfor all four derivatives in order to quantify their cellular uptake. In Figures 23 to37 (inclusive) the internalization is shown via confocal microscopy in 3 differentconcentrations for each conjugate.iCPP-D-Arg-Aib-NH2-5(6)-FAM (50 M, 20 M, m at 30 and 60 min)Figure 23. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM in after treatment (right). Figure 24. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM Figure 25. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM Figure 26. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM Figure 27. Confocal microscopy of the localization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM Figures 23, 24, 25, 26 and 27 show the internalization of iCPP-D-Arg-Aib-NH2- 5(6)-FAM into HeLa cancer cells, which were incubated for 30 and 60 minutes with 50 conjugate. At a concentration of 50 fluorescence signal of the same intensity is observed at both 30 and 60 minutes of incubation. However, the fluorescence intensity is slightly reduced with respect to the higher concentration. The iCPP-D-Arg-Aib-NH2-5(6)-FAM is stable and appears to enter both the cytoplasm and the cell nucleus. -- - - (50 M, 20 M, m at 30 and 60 min)Figure 28. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in treatment (right). Figure 29. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in Figure 30. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in Figure 31. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in Figure 32. Confocal microscopy of the localization of iCPP-D-Lys-5(6)-FAM in min after treatment. Figures 28, 29, 30, 31 and 32 show the internalization of the iCPP-D-Lys-5(6)- FAM into HeLa cancer cells, which were incubated for 30 and 60 minutes with50 M, conjugate. At a concentration of 50 M and 20and 60 minutes of incubation, as well as a vesicular system at 60 minutes of observed, slightly lower at 60 incubation minutes, as well as a very strong vesicular system. The fluorescence intensity between the two concentrations is similar. The iCPP-D-Lys-5(6)-FAM is highly stable and appears to enter both the cytoplasm and the cell nucleus. -- - - -5(6)-FAMFigure 33. Confocal microscopy of the localization of iCPP-D-Arg-D- -5(6)-FAM Figure 34. Confocal microscopy of the localization of iCPP-D-Arg-D- -5(6)-FAM Figure 35. Confocal microscopy of the localization of iCPP-D-Arg-D- -5(6)-FAM Figure 36. Confocal microscopy of the localization of iCPP-D-Arg-D- -5(6)-FAM Figure 37. Confocal microscopy of the localization of iCPP-D-Arg-D- -5(6)-FAM Figures 33, 34, 35, 36 and 37 show the internalization of iCPP-D-Arg-D- leucinamide-5(6)-FAM into HeLa cancer cells, which were incubated for 30and 60 minutes with 50 conjugate. At theconcentration of 50 lower at 60 minutes of incubation, as well as a strong vesicular system which fluorescence signal of the same intensity is observed at both 30 and 60 minutes of incubation, as well as an intense vesicular system. iCPP-D-Arg-D- leucinamide-5(6)-FAM peptide is stable and appears to enter both the cytoplasm and the cell nucleus. iCPP-DOTA derivativesSome iCPP derivatives were derivatised with DOTA as a proof of concept thatthe iCPP derivatives can be further derivatised.The synthesis of 1-(acetic acid)-4,7,10-tris(tert-butoxycarbonylmethyl)- 1,4,7,10-tetraaza-cyclododecane was carried out starting from cyclen according to the published procedure in the literature (Li C, Winnard P Jr, Bhujwalla ZM. Facile synthesis of 1-(acetic acid)-4,7,10-tris(tert- butoxycarbonylmethyl)-1,4,7,10-tetraaza-cyclododecane: a reactive precursorchelating agent. Tetrahedron Lett. 2009; 50(24):2929-2931).

[0005] Scheme 1: Synthetic procedure of 1-(acetic acid)-4,7,10-tris(tert- butoxycarbonylmethyl)-1,4,7,10-tetraaza-cyclododecane. To a suspension of cyclen (1g, 5.81 mmol) and triethylamine (TEA) (2.59ml, 18.56 mmol) in acetonitrile (60 mL) was added a solution of t-butyl bromoacetate (2.66ml, 17.98 mmol) dropwise over a period of 0.5 h. After 24 hof vigorous stirring at 70oC, the reaction mixture was removed in vaccuo andwater (20 mL) was added. The mixture was extracted 3× with ethyl acetate (3 × 30 mL). The organic phases were combined and further washed 2× with brine. The organic solution was dried with Na2SO4and the solvent was removed under reduced pressure to leave a crude product which was pure enough to be carried out to the next reaction. Yield: 2.67g (89%).1H NMR (500 MHz, CDCl3(m, 8H), 3.10 (m, 4H), 3.29 (s, 2H), 3.38 (s, 4H), 10.03 (br s, 1H);13C NMR 169.5, 170.4. Synthesis of 1-(ethyl acetate)-4,7,10-tris(tert-butoxycarbonylmethyl)-1,4,7,10- tetraazacyclododecane. 1,4,7-tris(tert-butoxycarbonyl-methyl)-1,4,7,10-tetraazacyclododecane (2.0 g, 3.8 mmol) were dissolved in 50 mL anhydrous acetonitrile and then anhydrous K2CO3(1.08g, 7.6 mmol, 2 equiv.) were charged in the round bottom flask. Then ethyl bromoacetate (634 mg, 3.8 mmol, 1.0 equiv.) was added. This suspension was stirred for 12 h under nitrogen atmosphere at 30 °C. The reaction was monitored by TLC until all starting material was consumed. After all the starting material was consumed, the reaction was filtered and the filtrate was evaporated. The crude product (light-yellow oil) was purified by flash chromatography on silica gel (dichloromethane / methane = 10 / 1 (v / v) to afford 2 as a light yellow powder (2.2 g, yield: 98%).1H NMR (400 MHz, CDCl3): d 4.04 (q, J = 7.3 Hz, 2H), 3.8 1.61 (broad andmultiple peaks with an integration of 24 H), 1.36 (s, 27H), 1.16 (t, J = 7.4 Hz, 3H);13C NMR (100 MHz, CDCl3): d 175.7, 172.4, 172.2, 82.0, 81.9, 59.2, 57.4, 56.2, 55.7, 53.0-50.8, 50.4-47.4, 28.2, 28.1, 13.3. Synthesis of 1-(acetic acid)-4,7,10-tris(tert-butoxycarbonylmethyl)- 1,4,7,10-tetraazacyclododecane 1-(ethyl acetate)-4,7,10-tris(tert-butoxycarbonylmethyl)-1,4,7,10- tetraazacyclododecane 3 (1.2g, 2.01 mmol was dissolved in a mixture (30 mL) of dioxane and NaOH with the ratio of 3:1 (v:v). This solution was stirred vigorously for 4 h at 50°C. Dioxane was removed in vacuo and water (20 mL) was added. The mixture was extracted 3× with dichloromethane (3 × 30 mL). The organic phases were combined and further washed 2× with brine. The organic solution was dried with Na2SO4 and the solvent was removed under reduced pressure to leave a transparent solid product. This was re-dissolved in 20 mL diethyl ether and allowed to re-crystallize by cooling the solution at 4 °C overnight. The final product 3 was obtained by filtration as a white solid with the yield of 83%.1H NMR (400 MHz, CDCl3): d 3.71 1.69 (very broad and multiple peaks withan integration corresponding to 24 H), 1.37 (s, 27H).13C NMR (100 MHz, CDCl3): d 175.9, 172.4, 172.1, 82.0, 81.9, 57.3, 56.3, 55.6, 53.2-50.9, 50.5-47.7, 28.3, 28.1.iCPP-DOTA conjugates were synthesized manually as described before (seepeptide synthesis section) on Rink Amide AM resin. Then the iCPP derivatives were derivatized with Fmoc-aminohexanoic acid to the -NH2terminal group ofthe last amino acid in each peptide (phenylalanine), as a common amino acid.Coupling reaction was performed in DMF using a molar ratio of fluorescein / DIC / HOBt / resin (3:3:3:1).Finally, 1-(acetic acid)-4,7,10-tris(tert-butoxycarbonylmethyl)-1,4,7,10-tetraaza-cyclododecane was conjugated to the -NH2 terminal group of the last amino-acid in each peptide, as a common amino acid. Coupling reaction was performed in DMF using a molar ratio of fluorescein / DIC / HOBt / resin (3:3:3:1). iCPP-DOTA derivatives formed:1. iCPP-DOTADOTA-6-Aminohexanoic acid-Phe-Arg-Arg-Lys-Arg-Arg-Lys-Arg-Cys- leucinamide 2. D-Lys-iCPP-DOTADOTA-6-Aminohexanoic acid-Phe-Arg-Arg-D-Lys-Arg-Arg-D-Lys-Arg-Cys- leucinamide 3. D-Arg-iCPP-DOTADOTA-6-Aminohexanoic acid-Phe-D-Arg-D-Arg-Lys-D-Arg-D-Arg-Lys-D-Arg- Cys-D-leucinamide Figure 38. Mass spectroscopy for the identification of the iCPP-DOTA conjugation where the fragments determined were: M+3 / 3 639.7227, M+4 / 4480.2940, M+5 / 5384.4369 and M+6 / 6 320.5321.Figure 39. Mass spectroscopy for the identification of the D-Lys-iCPP-DOTA conjugation where the fragments determined were: M+4 / 4480.3426 and +5 / 5 384.4712. Figure 40. Mass spectroscopy for the identification of the D-Arg-iCPP-DOTAconjugation where the fragments determined were: M+3 / 3 640.1245, M+4 / 4480.3421 and M+5 / 5384.4367.iCPP-DOTA, D-Lys-iCPP-DOTA and D-Arg-iCPP-DOTA are currently beingevaluated as iCPP containing conjugates and derivatives of iCPP containingconjugates. It is expected that iCPP-DOTA, D-Lys-iCPP-DOTA and D-Arg-iCPP-DOTA will show effectiveness as carriers of biologically activemolecules. References The following references are included to provide background information and to provide more detail on experimental protocols, where necessary. The following references are incorporated by reference in their entirety.1. Uzman, A., Molecular Cell Biology, Sixth Edition. Biochemistry andMolecular Biology Education, 2010.38(1): p.60-61.2. Aguirre, T.A., et al., Current status of selected oral peptide technologiesin advanced preclinical development and in clinical trials. Adv Drug Deliv Rev, 2016.106(Pt B): p.223-241.3. Moroz, E., S. Matoori, and J.C. Leroux, Oral delivery of macromoleculardrugs: Where we are after almost 100years of attempts. Adv Drug Deliv Rev, 2016.101: p.108-121.4. Bechara, C. and S. Sagan, Cell-penetrating peptides: 20 years later,where do we stand? FEBS Lett, 2013.587(12): p.1693-702.5. Habault, J. and J.L. Poyet, Recent Advances in Cell PenetratingPeptide-Based Anticancer Therapies. Molecules, 2019.24(5).6. Pujals, S., et al., D-SAP: a new, noncytotoxic, and fully proteaseresistant cell-penetrating peptide. ChemMedChem, 2008.3(2): p.296-301.7. Raucher, D. and J.S. Ryu, Cell-penetrating peptides: strategies foranticancer treatment. Trends Mol Med, 2015.21(9): p.560-70.8. Lu, L., et al., Vascular-homing peptides for cancer therapy. Biomedicine& Pharmacotherapy, 2017.92: p.187-195.9. Arap, W., R. Pasqualini, and E. Ruoslahti, Cancer treatment by targeteddrug delivery to tumor vasculature in a mouse model. Science, 1998. 279(5349): p.377-80.10. Pasqualini, R., E. Koivunen, and E. Ruoslahti, Alpha v integrins asreceptors for tumor targeting by circulating ligands. Nat Biotechnol, 1997. 15(6): p.542-6.11. Seidi, K., et al., NGR (Asn-Gly-Arg)-targeted delivery of coagulase totumor vasculature arrests cancer cell growth. Oncogene, 2018. 37(29): p. 3967-3980.12. Curnis, F., A. Sacchi, and A. Corti, Improving chemotherapeutic drugpenetration in tumors by vascular targeting and barrier alteration. J Clin Invest, 2002.110(4): p.475-82.13. Sacchi, A., et al., Crucial role for interferon gamma in the synergismbetween tumor vasculature-targeted tumor necrosis factor alpha (NGR-TNF) and doxorubicin. Cancer Res, 2004.64(19): p.7150-5.14. Zarovni, N., L. Monaco, and A. Corti, Inhibition of tumor growth byintramuscular injection of cDNA encoding tumor necrosis factor alpha coupled to NGR and RGD tumor-homing peptides. Hum Gene Ther, 2004. 15(4): p. 373-82.15. Sacchi, A., et al., Synergistic antitumor activity of cisplatin, paclitaxel,and gemcitabine with tumor vasculature-targeted tumor necrosis factor-alpha. Clin Cancer Res, 2006.12(1): p.175-82.16. Garde, S.V., et al., Binding and internalization of NGR-peptide-targetedliposomal doxorubicin (TVT-DOX) in CD13-expressing cells and its antitumor effects. Anti-Cancer Drugs, 2007.18(10).17. Li, Y.M. and W.A. Hall, Cell surface receptors in malignant glioma.Neurosurgery, 2011.69(4): p.980-94; discussion 994.18. Desgrosellier, J.S. and D.A. Cheresh, Integrins in cancer: biologicalimplications and therapeutic opportunities. Nat Rev Cancer, 2010. 10(1): p. 9- 22.19. Avraamides, C.J., B. Garmy-Susini, and J.A. Varner, Integrins inangiogenesis and lymphangiogenesis. Nat Rev Cancer, 2008.8(8): p.604-17.20. Ruoslahti, E., RGD and other recognition sequences for integrins. AnnuRev Cell Dev Biol, 1996.12: p.697-715.21. Ruoslahti, E. and M.D. Pierschbacher, Arg-Gly-Asp: a versatile cellrecognition signal. Cell, 1986.44(4): p.517-8.22. Schiffelers, R.M., et al., Cancer siRNA therapy by tumor selectivedelivery with ligand-targeted sterically stabilized nanoparticle. Nucleic Acids Res, 2004.32(19): p. e149.23. Jiang, J., et al., Sequential treatment of drug-resistant tumors withRGD-modified liposomes containing siRNA or doxorubicin. Eur J Pharm Biopharm, 2010.76(2): p.170-8.24. Alam, M.R., et al., Intracellular delivery of an anionic antisenseoligonucleotide via receptor-mediated endocytosis. Nucleic acids research, 2008.36(8): p.2764-2776.25. Haubner, R., et al., Noninvasive imaging of alpha(v)beta3 integrinexpression using 18F-labeled RGD-containing glycopeptide and positron emission tomography. Cancer Res, 2001.61(5): p.1781-5.26. Chen, X., P.S. Conti, and R.A. Moats, In vivo near-infrared fluorescenceimaging of integrin alphavbeta3 in brain tumor xenografts. Cancer Res, 2004. 64(21): p.8009-14.27. Svensen, N., J.G. Walton, and M. Bradley, Peptides for cell-selectivedrug delivery. Trends Pharmacol Sci, 2012.33(4): p.186-92.28. Kapoor, P., et al., TumorHoPe: a database of tumor homing peptides.PLoS One, 2012.7(4): p. e35187.29. Diamantis, D.A., et al., Biotin-Yellow a biotin guided NIR turn-onfluorescent probe for cancer targeted diagnosis. Sensors and Actuators B: Chemical, 2021.337: p.129807.30. KING, D.S., C.G. FIELDS, and G.B. FIELDS, A cleavage method whichminimizes side reactions following Fmoc solid phase peptide synthesis. International Journal of Peptide and Protein Research, 1990. 36(3): p. 255- 266.31. Sarin, V.K., et al., Quantitative monitoring of solid-phase peptidesynthesis by the ninhydrin reaction. Analytical Biochemistry, 1981. 117(1): p. 147-157.32. Kreisl, T.N., et al., Continuous daily sunitinib for recurrent glioblastoma.J Neurooncol, 2013.111(1): p.41-8.33. McNamara, M.G. and W.P. Mason, Antiangiogenic therapies inglioblastoma multiforme. Expert Review of Anticancer Therapy, 2012.12(5): p. 643-654.34. Schnell, O., et al., Expression of integrin alphavbeta3 in gliomascorrelates with tumor grade and is not restricted to tumor vasculature. Brain Pathol, 2008.18(3): p.378-86.35. -mediatedovarian cancer cell adhesion and motility in an RGD-dependent fashion. The International Journal of Biochemistry & Cell Biology, 2005.37(3): p.590-603. 36. tumors using 89Zr-RGD peptides. Mol Imaging Biol, 2011.13(6): p.1224-33.37. Ahluwalia, M.S., et al., Targeting SRC in glioblastoma tumors and brainmetastases: Rationale and preclinical studies. Cancer Letters, 2010.298(2): p. 139-149.38. Kuphal, S., R. Bauer, and A.K. Bosserhoff, Integrin signaling inmalignant melanoma. Cancer Metastasis Rev, 2005.24(2): p.195-222.39. Dobrucki, L.W., et al., Analysis of angiogenesis induced by local IGF-1expression after myocardial infarction using microSPECT-CT imaging. J Mol Cell Cardiol, 2010.48(6): p.1071-9.40. Temming, K., et al., RGD-based strategies for selective delivery oftherapeutics and imaging agents to the tumour vasculature. Drug Resist Updat, 2005.8(6): p.381-402.41. Garanger, E., D. Boturyn, and P. Dumy, Tumor targeting with RGDpeptide ligands-design of new molecular conjugates for imaging and therapy of cancers. Anticancer Agents Med Chem, 2007.7(5): p.552-8.42. Liu, S., Radiolabeled multimeric cyclic RGD peptides as integrinalphavbeta3 targeted radiotracers for tumor imaging. Mol Pharm, 2006. 3(5): p.472-87.43. Rosca, E.V., et al., Development of a biomimetic peptide derived fromcollagen IV with anti-angiogenic activity in breast cancer. Cancer Biol Ther, 2011.12(9): p.808-17. When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components. The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof. Although certain example embodiments of the invention have been described, the scope of the appended claims is not intended to be limited solely to these embodiments. The claims are to be construed literally, purposively, and / or to encompass equivalents.

Claims

Claims1. A compound comprising the formula X1-X2-X3-X4-X5-X6-X7-X8-X9-X10-X11-X12(Formula I), wherein: X1 is absent or present; when present X1 is a fluorophore, a contrastagent, a drug, a biological cargo, a linker, or a homing peptide; X2 is absent or present; when present X2 is an acetyl, a straight chainalkanoyl group, a branched alkanoyl group, a cyclic alkanoyl group, an aminohexanoic acid linker, substituted or unsubstituted C1-C26 alkyl, substituted or unsubstituted C1-C26chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26alkynyl, C1-C26 alkyl substituted with one or more substituted or unsubstituted benzyl groups, or C1-C26alkyl substituted with one or more substituted or unsubstituted triazole groups; X3 is phenylalanine (F), alanine (A), valine (V), isoleucine (I), leucine(L), methionine (M), tyrosine (Y), tryptophan (W) or another hydrophobic aminoacid group; X4 is arginine (R) or D-arginine;X5is arginine (R) or D-arginine; X6is lysine (K), D-lysine, arginine (R), D-arginine, histidine (H), D- histidine or ornithine; optionally, wherein X6is unsubstituted or substituted; when substituted, X6is substituted by a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; X7 is arginine (R) or D-arginine;X8 is arginine (R) or D-arginine;X9 is lysine (K), D-lysine, arginine (R), D-arginine, histidine (H), D-histidine or ornithine; optionally, wherein X9is unsubstituted or substituted; when substituted, X9is substituted by a fluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homing peptide; X10 is arginine (R) or D-arginine;2X11 is cysteine (C), a cysteine derivative, D-cysteine, glycine, D-glycine,methionine, D-methionine or penicillamine; optionally, wherein X11is unsubstituted or substituted; when substituted, X11is substituted by afluorophore, a contrast agent, a drug, a biological cargo, a linker, or a homingpeptide; and,leucine, D-leucinamide, 2-aminoisobutyric acid or 2-amino-2-methylpropanamide;wherein, X13 is selected from the group consisting of -NH2, -SH2,-SH-W, -OH, -N3, -NH-W, -W or -O-W, wherein W is selected from thegroup consisting of: -CH2CCH, -(CH2)2CCH, -(CH2)3CCH, -(CH2)4CCH, -(CH2)5CCH, -(CH2)6CCH, -CH2N3, -(CH2)2N3, -(CH2)3N3, -(CH2)4N3, - (CH2)5N3, -(CH2)6N3, -CH2OH, -(CH2)2OH, -(CH2)3OH, -(CH2)4OH, - (CH2)5OH or -(CH2)6OH; or a tautomer, polymorph, hydrate, solvate, metabolite, prodrug, formulate or pharmaceutically acceptable salt thereof.

2. The compound of claim 1, wherein X1 is absent, X2 is absent, X12 is3. The compound of claim 1 or claim 2, wherein X4, X5, X7, X8 and X10 arearginine (R); or, wherein X4, X5, X7, X8and X10are D-arginine (R).

34. The compound of any one of claims 1 to 3, wherein X3 is phenylalanine(F).

5. The compound of any one of claims 1 to 4, wherein X6 and X9 are lysine(K); or, wherein X6and X9are D-lysine (K).

6. The compound of any one of claims 1 to 5, wherein X11 is substituted orunsubstituted cysteine (C).

7. The compound of any one of claims 1 to 6, wherein X12 is leucine (L),leucinamide, D-leucine or D-leucinamide.

8. The compound of any one of claims 1 to 7, wherein X4, X5, X7, X8 andX10are D-arginine (R) and X12is or 2-amino-2-methylpropanamide.

9. The compound of any one of claims 1 to 7, wherein the compoundcomprises FRRKRRKRC-leucinamide.

10. The compound of any one of claims 1 to 9, wherein one of, two of, threeof or four of X1, X6, X9and / or X11are selected from, or substituted withcompounds selected from, the group consisting of:5.

611. The compound of any one of claims 1 to 10, wherein X2 is selected fromthe group consisting of: substituted or unsubstituted C1-C26alkyl, substituted or unsubstituted C1-C26chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26 alkynyl, C1-C26 alkyl substituted with one or more substituted or unsubstituted benzyl groups, C1-C26alkyl substituted with one or more substituted or unsubstituted triazole groups; or, -CH2CH3, -(CH2)2CH3, -(CH2)3CH3, -(CH2)4CH3, -(CH2)5CH3, -(CH2)6CH3, - CH2CH(CH3)2, -(CH2)2CH(CH3)2, -(CH2)3CH(CH3)2or -(CH2)4CH(CH3)2; or, -CH2CH2-, -(CH2)2CH2-, -(CH2)3CH2-, -(CH2)4CH2-, -(CH2)5CH2-, -(CH2)6CH2-, -CH2C(CH3)2-, -(CH2)2C(CH3)2-, -(CH2)3C(CH3)2- or -(CH2)4C(CH3)2-; or,-CH2Cl, -(CH2)2Cl, -(CH2)3Cl, -(CH2)4Cl, -(CH2)5Cl, -(CH2)6Cl, -CH2Br, - (CH2)2Br, -(CH2)3Br, -(CH2)4Br, -(CH2)5Br, -(CH2)6Br, -CH2I, -(CH2)2I, -(CH2)3I, - (CH2)4I, -(CH2)5I or -(CH2)6I; or,-CHCl-, -CHBr- or -CHI-; or,-CH2CCH, -(CH2)2CCH, -(CH2)3CCH, -(CH2)4CCH, -(CH2)5CCH or - (CH2)6CCH; or,-CH2CC-, -(CH2)2CC-, -(CH2)3CC-, -(CH2)4CC-, -(CH2)5CC- or -(CH2)6CC-; or,-CH2N3, -(CH2)2N3, -(CH2)3N3, -(CH2)4N3, -(CH2)5N3or -(CH2)6N3; or, -CHN3-; or, -CH2SH, -(CH2)2SH, -(CH2)3SH, -(CH2)4SH, -(CH2)5SH or -(CH2)6SH; or,-CH2S-, -(CH2)2S-, -(CH2)3S-, -(CH2)4S-, -(CH2)5S- or -(CH2)6S-; or,-CH2COOH, -(CH2)2COOH, -(CH2)3COOH, -(CH2)4COOH, -(CH2)5COOH, - (CH2)6COOH, -CH2COOR2, -(CH2)2COOR2, -(CH2)3COOR2, -(CH2)4COOR2, - (CH2)5COOR2or -(CH2)6COOR2; wherein R2is substituted or unsubstituted C1- C26alkyl; or, -CH2Ar, -(CH2)2Ar, -(CH2)3Ar, -(CH2)4Ar, -(CH2)5Ar, -(CH2)6Ar, -CH2CHArCH3 or -CH2CHArCH2CH3;7 whereinwherein A1, A2, A3, A4 and A5 are each selected independently but not limited to H, NO2, OH, O-alkyl or O-methyl or substituted or unsubstituted C1-C26 alkyl, substituted or unsubstituted C1-C26 chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26 alkynyl, C1-C26 alkyl substituted with one or more benzyl, pyrrolyl, furanyl, thiophenyl, flavynyl, chromenyl, coumarinoyl, quinolinyl, indonyl, pyridinyl or substituted benzyl, pyrrolyl, furanyl, thiophenyl, flavynyl, chromenyl, coumarinoyl, quinolinyl, indonyl, pyridinyl groups; or, -CH2Tz, -(CH2)2Tz, -(CH2)3Tz, -(CH2)4Tz, -(CH2)5Tz, -(CH2)6Tz, -CH2CHTzCH3 or -CH2CHTzCH2CH3; whereinwherein B is selected but not limited to: substituted or unsubstituted C1-C26alkyl, substituted or unsubstituted C1-C26 chloroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted benzyl, substituted or unsubstituted C1-C26alkynyl, C1-C26alkyl substituted with one or more benzyl, pyrrolyl, furanyl, thiophenyl, flavynyl, chromenyl, coumarinoyl, quinolinyl, indonyl, pyridinyl or substituted benzyl, pyrrolyl, furanyl, thiophenyl, flavynyl, chromenyl, coumarinoyl, quinolinyl, indonyl, pyridinyl groups.

12. The compound of any one of claims 1 to 11, wherein X11 is cysteine (C)substituted by a homing peptide, wherein the cysteine residues at X11and in8the homing peptide are linked by a -S-S- bond; optionally, wherein the homingpeptide has the sequence CRGDR-COOH (SEQ ID NO: 2).

13. The compound of any one of claims 1 to 12, wherein the drug at eachoccurrence is independently selected from the group consisting of: sunitinib ora derivative of sunitinib (for example SB1), gemcitabine or a derivative ofgemcitabine, SN-38 (7-ethyl-10-hydroxycamptothecin) or a derivative of SN- 38, doxorubicin or a derivative of doxorubicin, paclitaxel or a derivative of paclitaxel, temozolomide or a derivative of temozolomide, EMA401 or a derivative of EMA401, camptothecin or a derivative of camptothecin, irinotecan or a derivative of irinotecan, bevacizumab or a derivative of bevacizumab, erlotinib or a derivative of erlotinib.

14. The compound of any one of claims 1 to 13, wherein the fluorophore ateach occurrence is independently selected from the group consisting of: 5(6)-FAM (5(6)-Carboxyfluorescein; IUPAC: 3',6'-dihydroxy-3-oxo-spiro[isobenzofuran-1(3H),9'-[9H]xanthene]-ar-carboxylic acid), Rhodamine B (IUPAC: N-[9-(2-carboxyphenyl)-6-(diethylamino)-3H-xanthen-3-ylidene]-N-ethylethanaminium), IR820 (IUPAC: 2-[2-[2-Chloro-3-[[1,3-dihydro-1,1-dimethyl-3-(4-sulfobutyl)-2H-benzo[e]indol-2-ylidene]-ethylidene]-1- cyclohexen-1-yl]-ethenyl]-1,1-dimethyl-3-(4-sulfobutyl)-1H-benzo[e]indolium hydroxide inner salt, sodium salt), Indocyanine green, Flav7, CH-1055, IR-1061 (IUPAC: 4-[2-[2-Chloro-3-[(2,6-diphenyl-4H-thiopyran-4-ylidene)ethylidene]-1-cyclohexen-1-yl]ethenyl]-2,6-diphenylthiopyryliumtetrafluoroborate) or IR-1048 (IUPAC: 1-Butyl-2-[2-[3-[(1-butyl-6-chlorobenz[cd]indol-2(1H)-ylidene)ethylidene]-2-chloro-1-cyclohexen-1- yl]ethenyl]-6-chlorobenz[cd]indolium tetrafluoroborate).

15. The compound of any one of claims 1 to 14, wherein X1 is DOTA(IUPAC: 2-[4,7,10-tris(carboxymethyl)-1,4,7,10-tetrazacyclododec-1-yl]acetic acid).

916. The compound of any one of claims 1 to 15, wherein X2 is 6-aminohexanoic acid.

17. A conjugate comprising the compound of any one of claims 1 to 16.

18. A conjugate comprising the compound of any one of claims 1 to 16,wherein the conjugate is of the formula:(conjugate S1ISR1).

19. A conjugate comprising the compound of any one of claims 1 to 16wherein the conjugate is of the formula:10(conjugate 5(6)-FAM-S1ISR1).

20. A pharmaceutical composition comprising a compound according to anyone of claims 1 to 16, or a conjugate of any one of claims 17 to 19, and apharmaceutically acceptable carrier.

21. A compound according to any one of claims according to any one ofclaims 1 to 16, or a conjugate of any one of claims 17 to 19, or apharmaceutical composition according to claim 20, for use in therapy.

22. A compound according to according to any one of claims 1 to 16, or aconjugate of any one of claims 17 to 19, or a pharmaceutical composition according to claim 20, for use in treating cancer.

23. The compound or pharmaceutical composition for use according toclaim 22, wherein the cancer is selected from the group consisting of: breast cancer, ovarian cancer, non-small cell lung cancer, pancreatic cancer and bladder cancer, glioblastoma, acute monocytic leukemia, acute myelogenous leukemia, acute myelomonocytic leukemia, acute promyelocytic leukemia,11 adult T-cell leukemia, adult T-cell lymphoma, astrocytoma, atypical carcinoid lung cancer, basal cell carcinoma, B-acute lymphocytic leukemia, B-cell acute lymphoblastic leukemia / lymphoma, bladder cancer, brain cancer, andbronchial cancer.

Images