Anticancer compound

Abstract

The present invention relates to the use of PM534 for the treatment of cancer.

Description

[0001] ANTICANCER COMPOUND

[0002] The present invention relates to the use of PM534 compound for the treatment of cancer.

[0003] BACKGROUND OF THE INVENTION

[0004] Microtubules are important components of the cytoskeleton networks in eukaryotic cells, responsible for cell shape maintenance and involved in the intracellular transport, cytoplasmic organization and mitosis. As they play a major role in cellular activities, microtubules have long been investigated as the drug target for cancer treatment.

[0005] Tubulin is a GTP-regulated protein that plays a central role in the formation of these microtubules. When bound to GTP, tubulin is in its active form, allowing it to self-assemble into microtubules. After the microtubules are formed, tubulin's intrinsic GTPase activity is activated, converting GTP into GDP. The GDP-bound form of tubulin is inactive, which leads to the disassembly of microtubules.

[0006] Currently, up to eight pharmacological regulatory sites on tubulin have been identified. Six of these sites namely, colchicine, vinca, maytansine, pironetin, gatorbulin and todalam bind compounds that inhibit microtubule formation through the inactivation of GTP-bound tubulin, classifying these compounds as microtubule-destabilizing agents (MDAs). The remaining two sites, taxane and laulimalide, bind compounds that promote microtubule formation by stabilizing the GDP-bound tubulin, known as microtubule-stabilizing agents (MSAs).

[0007] In clinical cancer therapy, only three regulatory sites are exploited: the vinca and maytansine sites, and the taxane site. Vinca alkaloids and taxanes are highly effective against different types of cancer. However, despite their efficacy, tubulin-targeting agents face significant limitations, including severe peripheral neurotoxicity and resistance mechanisms such as drug efflux pumps (mediated by ATP-binding cassette (ABC) transporters) and the overexpression of p-lll tubulin isoforms, which reduce their therapeutic potential.

[0008] International patent application WO2020 / 127194 discloses a compound of general Formula I and its efficacy in vitro in solid tumours, in particular NSCLC, pancreas, breast, and colorectal cancer.

[0009]

[0010] SUMMARY OF THE INVENTION

[0011] In a first aspect, the present invention is directed to PM534,

[0012]

[0013] for use in the treatment of solid tumours selected from prostate cancer, gastric cancer, sarcoma and small cell lung cancer.

[0014] In a yet further aspect of the present invention, there is provided the use of PM534, in the manufacture of a medicament for the treatment of cancer selected from prostate cancer, gastric cancer, sarcoma and small cell lung cancer.

[0015] In a yet further aspect of the present invention, there is provided a method of treatment of cancer selected from prostate cancer, gastric cancer, sarcoma and small cell lung cancer, wherein PM534 is administered.

[0016] In a yet further aspect of the present invention, there is provided a pharmaceutical composition or dosage form comprising PM534 according to the present invention, for use in the treatment of cancer selected from prostate cancer, gastric cancer, sarcoma and small cell lung cancer.

[0017] In a yet further aspect of the present invention, there is provided a kit comprising a therapeutically effective amount of compound PM534, according to the present invention, and a pharmaceutically acceptable carrier.

[0018] In a further aspect, there is provided PM534 for use in a method of inhibiting growth of a cell, said method comprising contacting a cell with PM534, wherein said cell is selected from a prostate cancer cell, a gastric cancer cell, a sarcoma cell and small cell lung cancer cell.In a yet further aspect of the present invention, there is provided a method for the prevention or treatment of cancer selected from prostate cancer, gastric cancer, sarcoma and small cell lung cancer, comprising administering an effective amount of PM534 according to the present invention, administering an effective amount of a pharmaceutical composition according to the present invention, or administering an effective amount of a dosage form according to the present invention to a patient in need thereof, notably a human.

[0019] In embodiments, PM534 is in the form of a pharmaceutically acceptable salt or ester thereof.

[0020] In embodiments, the compound PM534 of the present invention is for use in the treatment of sarcoma.

[0021] In embodiments, the compound PM534 of the present invention is for use in the treatment of soft tissue sarcoma.

[0022] In embodiments, the compound PM534 of the present invention is for use in the treatment of bone sarcoma.

[0023] In embodiments, the compound PM534 of the present invention is for use in the treatment of cic-rearranged sarcoma.

[0024] In embodiments, the compound PM534 of the present invention is for use in the treatment of Ewing sarcoma.

[0025] In embodiments, the compound PM534 of the present invention is for use in the treatment of fibrosarcoma

[0026] In embodiments, the compound PM534 of the present invention is for use in the treatment of uterine sarcoma.

[0027] In embodiments, the compound PM534 of the present invention is for use in the treatment of liposarcoma (LPS).

[0028] In embodiments, the compound PM534 of the present invention is for use in the treatment of leiomyosarcoma (LMS).

[0029] In embodiments, the compound PM534 of the present invention is for use in the treatment of dedifferentiated liposarcoma (DDLPS).

[0030] In embodiments, the compound PM534 of the present invention is for use in the treatment of gastric cancer.In embodiments, the compound PM534 of the present invention is for use in the treatment of stomach adenocarcinoma, gastroesophageal junction adenocarcinoma, gastrointestinal neuroendocrine tumors, gastrointestinal stromal tumors and primary gastric lymphoma.

[0031] In embodiments, the compound PM534 of the present invention is for use in the treatment of carcinoma gastric cancer.

[0032] In embodiments, the compound PM534 of the present invention is for use in the treatment of adenocarcinoma gastric cancer.

[0033] In embodiments, the compound PM534 of the present invention is for use in the treatment of prostate cancer.

[0034] In embodiments, the compound PM534 of the present invention is for use in the treatment of neuroendocrine prostate cancer.

[0035] In embodiments, the compound PM534 of the present invention is for use in the treatment of adenocarcinoma prostate cancer.

[0036] In embodiments, the compound PM534 of the present invention is for use in the treatment of carcinoma prostate cancer.

[0037] In embodiments, the compound PM534 of the present invention is for use in the treatment of small cell lung cancer.

[0038] In embodiments, the compound PM534 of the present invention is for use in the treatment of extensive stage small cell lung cancer.

[0039] In embodiments, the compound PM534 of the present invention is for use in the treatment of limited stage small cell lung cancer.

[0040] FIGURES

[0041] Figure 1 : Dose-response curve for PM534 in 22Rv1 prostate cancer cell line incubated for 72h.

[0042] Figure 2: Dose-response curve for PM534 in LNCap prostate cancer cell line incubated for 72h.

[0043] Figure 3: Dose-response curve for PM534 in NCI-H660 prostate cancer cell line incubated for 72h.

[0044] Figure 4: Dose-response curve for PM534 in PC-3 prostate cancer cell line incubated for 72h.

[0045] Figure 5: Dose-response curve for PM534 in VCap prostate cancer cell line incubated for 72h.Figure 6: Dose-response curve for PM534 in AGS gastric cancer cell line incubated for 72h.

[0046] Figure 7: Dose-response curve for PM534 in CLS gastric cancer cell line incubated for 72h.

[0047] Figure 8: Dose-response curve for PM534 in NCI-N87 gastric cancer cell line incubated for 72h. Figure 9: Dose-response curve for PM534 in HGC-27 gastric cancer cell line incubated for 72h.

[0048] Figure 10: Dose-response curve for PM534 in Hs746t gastric cancer cell line incubated for 72h.

[0049] Figure 11 : Dose-response curve for PM534 in A673 sarcoma cell line incubated for 72h.

[0050] Figure 12: Dose-response curve for PM534 in HT1080 sarcoma cell line incubated for 72h.

[0051] Figure 13: Dose-response curve for PM534 in MES-SA sarcoma cell line incubated for 72h.

[0052] Figure 14: Dose-response curve for PM534 in RD-ES sarcoma cell line incubated for 72h.

[0053] Figure 15: Dose-response curve for PM534 in SK-NEP-1 sarcoma cell line for during 72h.

[0054] Figure 16: Dose-response curve for PM534 in SW872 sarcoma cell line incubated for 72h.

[0055] Figure 17: Dose-response curve for PM534 in TC32 sarcoma cell line incubated for 72h.

[0056] Figure 18: Dose-response curve for PM534 in TC71 sarcoma cell line incubated for 72h.

[0057] Figure 19: Dose-response curve for PM534 in DMS-53 SCLC cell line incubated for 72h.

[0058] Figure 20: Distribution of cell cycle phases following a 24-hours incubation period of 22Rv1 (prostate) with 10 nM of PM534. Results are presented as the median percentage (n=3).

[0059] Figure 21: Representative picture of the PM534-induced multinucleated cells (in light gray; under the same experimental conditions than in Figure 20) in the 22Rv1 cell line evaluated. Figure 22A to 22H: Time curve showing the survival probability (%) of tumor xenografted mice treated with either placebo (line and symbols, grey) or PM534 (line and symbols, black). PM534 2.5 mg / kg was administered to mice bearing VCaP (Figure 22A); at 3.75 mg / kg to mice bearing 22Rv1 tumors (Figure 22B); at 3.75 mg / kg to mice bearing H660 tumors (Figure 22C); at 5 mg / kg to mice bearing Hs746t (Figure 22D); at 5 mg / kg to mice bearing HGC-27 (Figure 22E); at 5 mg / kg to mice bearing HT-1080 (Figure 22F); at 2.5 mg / kg to mice bearing H526 (Figure 22G); at 3.56 mg / kg to mice bearing H82 (Figure 22H). Treatments of HT-1080 and H82 were intravenously given on days 0, and 7. The treatments of the other tumors were intravenously given on days 0, 7 and 14 (black line). Inlets: Box-and-Whisker plots of tumor volume on the last day of 100% alive population in the placebo-treated group.Figure 23: Box-and-Whisker plots of cell apoptosis found in tumors harvested from mice bearing VCaP and 22Rv1 tumors, 24 hours after the second dose of PM534 (placebo line and symbols, grey / PM534 line and symbols, black).

[0060] Figure 24: shows tumour volume evaluation on xenografts models with H660 prostate cell line treated intravenously with PM534 at 3.75 mg / kg by weekly administration for 3 consecutive weeks.

[0061] Figure 25: shows tumour volume evaluation on xenografts models with VCap prostate cell line treated intravenously with PM534 at 2.5 mg / kg by weekly administration for 3 consecutive weeks.

[0062] Figure 26: shows tumour volume evaluation on xenografts models with 22Rv1 prostate cell line treated intravenously with PM534 at 3.75 mg / kg by weekly administration for 3 consecutive weeks.

[0063] Figure 27: shows tumour volume evaluation on xenografts models with HGC-27 gastric cell line treated intravenously with PM534 at 5 mg / kg by weekly administration for 3 consecutive weeks.

[0064] Figure 28: shows tumour volume evaluation on xenografts models with Hs746t gastric cell line treated intravenously with PM534 at 5 mg / kg by weekly administration for 3 consecutive weeks.

[0065] Figure 29: shows tumour volume evaluation on xenografts models with HT-1080 sarcoma cell line treated intravenously with PM534 at 5 mg / kg by weekly administration for 2 consecutive weeks.

[0066] Figure 30: shows tumour volume evaluation on xenografts models with H82 small-cell lung cancer cell line treated intravenously with PM534 at 3.56 mg / kg by weekly administration for 2 consecutive weeks (3 / 4 MTD).

[0067] Figure 31: shows tumour volume evaluation on xenografts models with H526 small-cell lung cancer cell line treated intravenously with PM534 at 2.5 mg / kg by weekly administration for 3 consecutive weeks (1 / 2 MTD).

[0068] Figures 32A and 32B: Changes of body weights (as mean %) of mice bearing different VCap or 22Rv1 xenografts and treated with PM534 (black) or placebo (grey) on days 0, 7 and 14. Data are expressed as mean±SD (n>6 / group).Figure 33: Changes of body weights (as mean %) of mice bearing STS149 leiomyosarcoma xenografts and treated with PM534 at 4.75 mg / kg (black) or placebo (grey). T symbol means mouse sacrificed due to tumour volume > 2000 mm3; symbol means mouse sacrificed due to body weight loss.

[0069] Figure 34: Changes of body weights (as mean %) of mice bearing STS22 leiomyosarcoma xenografts and treated with PM534 at 4.75 mg / kg (black) or placebo (grey). T symbol means mouse sacrificed due to tumour volume > 2000 mm3; symbol means mouse sacrificed due to body weight loss.

[0070] Figure 35: Changes of body weights (as mean %) of mice bearing STS112 dedifferentiated liposarcoma xenografts and treated with PM534 at 4.75 mg / kg (black) or placebo (grey). T symbol means mouse sacrificed due to tumour volume > 2000 mm3; symbol means mouse sacrificed due to body weight loss.

[0071] Figure 36: Tumor volume evaluation in xenograft murine model injected with STS149 leiomyosarcoma cell line with the compound of the present invention PM534 at dose of 4.75 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 36). 1 murine model treated with placebo was sacrificed on Day 13. 3 murine models treated with PM534 were sacrificed between Day 9 and Day 10 due to weight loss or a tumor volume higher than 2000 mm3.

[0072] Figure 37:Tumour volume evaluation in xenograft murine model injected with STS22 leiomyosarcoma cell line with the compound of the present invention PM534 at dose of 4.75 mg / kg by weekly administration for 3 consecutive weeks. 1 murine model treated with placebo was sacrificed on Day 13.

[0073] Figure 38: Tumour volume evaluation in xenograft murine model injected with STS112 dedifferentiated liposarcoma cell line with the compound of the present invention PM534 at dose of 4.75 mg / kg by weekly administration for 3 consecutive weeks. 2 murine model treated with placebo was sacrificed on Day 7 and 1 was sacrificed on Day 11 due to a tumor volume higher than 2000 mm3.

[0074] DETAILED DESCRIPTION PM534 is a synthetic analogue of a natural compound originally isolated from the sponge Discordemia sp. (order Lithistida, family Theonellidae) isolate.

[0075] This sponge was collected by hand using Rebreather diving system in Halmahera, Indonesia (2'16.307' N / 127° 44.466' E) at depths ranging between 6 and 73 m. A sample of the specimen was deposited at the Centre for Advanced Studies of Blanes in Girona, Spain, with the reference code HALM-706.

[0076] PM534 binds to the whole colchicine binding domain (CBD), covering four of the five pharmacophore centers, and displays high tubulin binding affinity.

[0077] In particular, PM534 makes contact with p-tubulin N-terminal domain (p-strands S5 and S6), helix H7, the intermediate domain (helices H8 and p-strands S8 and S10,) and a-tubulin T5 loop

[0078] Remarkably, it has been found that PM534 has a powerful antitumor activity in lung epithelial, small and non-small lung cancer cells (SCLC and NSCLC), breast, colon, prostate, gastric, and pancreas cancer and sarcoma and, it is able to override typical resistance mechanisms against Microtubule-Targeting Agents MTAs (overexpression of detox pumps or specific tubulin pill isotype).

[0079] PM534 is disclosed as Compound 76 and can be synthesised following the processes disclosed in WO 2020 / 127194.

[0080] The following embodiments apply to all aspects of the present invention.

[0081] In the present invention, the term “treating”, as used herein, unless otherwise indicated, means reversing, attenuating, alleviating or inhibiting the progress of the disease or condition to which such term applies, or one or more symptoms of such disorder or condition. The term “treatment”, as used herein, unless otherwise indicated, refers to the act of treating as “treating” is defined immediately above.

[0082] In embodiments, PM534 may be in the form of a pharmaceutically acceptable salt or ester thereof.

[0083] The terms “pharmaceutically acceptable salt” and “ester” refers to any pharmaceutically acceptable salt or ester which, upon administration to the patient is capable of providing (directly or indirectly) a compound as described herein. However, it will be appreciated that non-pharmaceutically acceptable salts also fall within the scope of the invention since those may be useful in the preparation of pharmaceutically acceptable salts. The preparation of salts can be carried out by methods known in the art.

[0084] For instance, pharmaceutically acceptable salts of compounds provided herein are synthesized from the parent compound, which contains a basic or acidic moiety, by conventional chemical methods. Generally, such salts are, for example, prepared by reacting the free acid or base forms of these compounds with a stoichiometric amount of the appropriate base or acid in water or in an organic solvent or in a mixture of both. Generally, nonaqueous media like ether, ethylacetate, ethanol, 2-propanol or acetonitrile can be used. Examples of the acid addition salts include mineral acid addition salts such as, for example, hydrochloride, hydrobromide, hydroiodide, sulfate, nitrate, phosphate, and organic acid addition salts such as, for example, acetate, trifluoroacetate, maleate, fumarate, citrate, oxalate, succinate, tartrate, malate, mandelate, methanesulfonate and p-toluenesulfonate. Examples of the alkali addition salts include inorganic salts such as, for example, sodium, potassium, calcium and ammonium salts, and organic alkali salts such as, for example, ethylenediamine, ethanolamine, N,N-dialkylenethanolamine, triethanolamine and basic aminoacids salts.

[0085] The compound of the invention may be in amorphous form or in crystalline form either as free compound or as solvate (e.g. hydrates) and it is intended that all forms are within the scope of the present invention. Methods of solvation are generally known within the art.

[0086] In addition, compounds referred to herein may exist in isotopically-labelled forms. All pharmaceutically acceptable salts, esters and isotopically labelled forms of the compound referred to herein, and mixtures thereof, are considered within the scope of the present invention.

[0087] It is provided pharmaceutical compositions of compound PM534 or a pharmaceutically acceptable salt or ester thereof that possess cytotoxic activities and its use as anticancer agent. The present invention further provides pharmaceutical compositions comprising a compound PM534 or a pharmaceutically acceptable salt or ester thereof, with a pharmaceutically acceptable carrier or diluent. Examples of pharmaceutical compositions include any solid (tablets, pills, capsules, granules, etc.) or liquid (solutions, suspensions or emulsions) composition for oral, topical or parenteral administration.

[0088] Administration of the compound PM534 or composition of the present invention may be by any suitable method, such as intravenous infusion, oral preparations, and intraperitoneal and intravenous administration.

[0089] The correct dosage of the compound PM534 will vary according to the particular formulation, the mode of application, and the particular situs, host and tumour being treated. Other factors like age, body weight, sex, diet, time of administration, rate of excretion, condition of the host, drug combinations, reaction sensitivities and severity of the disease shall be taken into account.

[0090] The compound of the invention has anticancer activity against several cancer types, particularly solid tumours.

[0091] In an embodiment, compound PM534 of the present invention is for use in the treatment of small-cell lung cancer.Lung cancer is a disease in which malignant (cancer) cells form in the tissues of the lung. The two major types of lung cancer are small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC).

[0092] SCLC comprises only about 13-15% of all lung cancers at diagnosis; however, SCLC is the more aggressive form of lung cancer. With SCLC, the cancer cells tend to grow quickly and travel to other parts of the body, or metastasize, more easily. Its incidence is associated with smoking, almost two thirds of patients present with advanced disease, and although response rates to chemotherapy are high, the benefit is short-lived. The median survival of patients with untreated SCLC is two to four months (Clark, 1998; Glisson, 2003; Davies, 2004).

[0093] According to the present invention, the small-cell lung cancer may be at an extensive or limited stage.

[0094] In another embodiment, the compound PM534 of the present invention is for use in the treatment of sarcoma.

[0095] Sarcoma is a rare type of cancer. It forms in the body’s connective tissue, which includes bone, muscle, fat and nerves. Sarcomas can occur at any age and in any part of the body. There are two main types of sarcomas: soft tissue sarcoma and bone sarcoma.

[0096] In an embodiment, the sarcoma is Ewing sarcoma.

[0097] In another embodiment, the sarcoma is cic-rearranged sarcoma.

[0098] In a further embodiment, the sarcoma is soft tissue sarcoma.

[0099] In another embodiment, the sarcoma is selected from fibrosarcoma, uterine sarcoma, liposarcoma (LPS), leiomyosarcoma (LMS) and dedifferentiated liposarcoma (DDLPS).

[0100] In a further embodiment, the compound PM534 of the present invention is for use in the treatment of gastric cancer.

[0101] Stomach cancer, which is also called gastric cancer, is a cancer that is caused by the uncontrolled growth of cells in the inner lining of the stomach, forming a mass or ulcer. There are different types of gastric cancers: stomach adenocarcinoma, gastroesophageal junction adenocarcinoma, gastrointestinal neuroendocrine tumors, gastrointestinal stromal tumors and primary gastric lymphoma.

[0102] In an embodiment, the gastric cancer is selected from carcinoma gastric cancer, and adenocarcinoma gastric cancer.

[0103] In an embodiment, the compound PM534 of the present invention is for use in the treatment ofprostate cancer.

[0104] Prostate cancer develops when abnormal cells form and grow in the prostate gland. The most common prostate cancer type is adenocarcinoma, while the less common types are small cell carcinomas, neuroendocrine tumors, sarcomas and transitional cell carcinomas.

[0105] In an embodiment, the prostate cancer is selected from neuroendocrine prostate cancer, adenocarcinoma prostate cancer, and carcinoma prostate cancer.

[0106] EXAMPLES

[0107] EXAMPLE 1: In vitro assays of PM534 in prostate and gastric cancer, sarcoma and small cell lung cancer cell lines

[0108] PM534 compound

[0109] PM534 was synthesized at PharmaMar, S.A. (Colmenar Viejo, Madrid, Spain) with a purity higher than 98%. For in vitro experiments, stock solutions of PM534 were prepared in DMSO at 1 mg / mL and stored at -20°C. Further dilutions with culture media were performed as necessary to achieve working solutions (DMSO concentration <1%) at the target concentrations of PM534 for each experimental setup. For xenograft experiments, PharmaMar S.A. manufactured lyophilized vials of PM534 (9 mg), which were reconstituted with water for injection and diluted with sterile saline to the final dosing concentration.

[0110] Cell lines

[0111] A panel of nineteen tumor cell lines representing four human tumors (prostate, gastric, sarcoma, and small cell lung cancer) were used throughout. All these cell lines were purchased from the American Type Culture Collection (ATCC), the European Collection of Authenticated Cell Cultures (ECACC), the German Collection of Microorganisms and Cell Cultures (DSMZ), or the Japanese Collection of Research Bioresources Cell Bank (JCRB Cell Bank). Cell lines were kept in vitro at 37°C in a humidified atmosphere of 5% CO2 in culture media recommended by the supplier, supplemented with 10% fetal bovine serum (FBS), 1% penicillin and streptomycin and 2 mM L-glutamine. Only low passage cells (between passages 3 and 7) were used throughout.

[0112] In vitro growth inhibition assays

[0113] Cell growth inhibition was analysed by MTT assay following Manufacturer's instructions (MTT Cell Proliferation Kit I; Roche Diagnostics). An appropriate number of cells, to reach a final cell density in the assay ranging from 5,000 to 15,000 cells per well depending on the cell line, were seeded in 96-well plates and allowed to stand in culture medium for 24 h at 37°C under 5% CO2 and 98% humidity.In vitro growth inhibition assays were performed after continuous exposure of cell cultures to increasing PM534 concentrations for 72 hours. PM534 or DMSO in culture medium were added to reach a final volume of 200 pL keeping PM534 concentration in a range covering 10 serial 2 / 5 dilutions starting from 0.1pg / mL (127 nM) in 1% (v / v) DMSO.

[0114] At this point a set of “time zero control plates” treated with 1% (v / v) DMSO were processed with MTT as described below. The rest of the plates were incubated during 72 h under the aforementioned environmental conditions. Afterwards 50 pL of a 1 mg / mL MTT solution in culture medium were added to the wells and incubated for 6-8 hours at 37°C to allow formazan crystals generation. Culture medium was then removed and 100 pL of neat DMSO added to each well to dissolve the formazan product into a coloured solution whose absorbance at 540 nm was finally measured in a PolarStar Omega microplate multilabel reader (BMG Labtech, Ortenberg, Germany).

[0115] All evaluations were performed at least in triplicate and the resulting data were fitted by nonlinear regression to a four-parameters logistic curve with Prism v5.0 software (GraphPad Prism Software v9.4.1, La Jolla, CA, USA) following the algorithm developed by the American National Cancer Institute (NCI). Such algorithm allows the calculation of three parameters defining the compound effect: GI50 (compound concentration that produces 50% of cell growth inhibition as compared to control cultures), TGI (compound concentration that causes total cell growth inhibition, i.e. a cytostatic effect, as compared to control cultures) and LC50 (compound concentration that produces 50% of net cell killing cytotoxic effect).

[0116] Briefly, if “Tz” is the number of cells at time zero, “C” is the number of cells after 72 h in DMSO-treated control wells, and “T” is the number of cells after 72 h in test wells, two different scenarios can be considered:

[0117] 1. If Tz < T < C (i.e. no effect or growth inhibition) cell survival is defined as:

[0118] % Cell survival=100 ■ ((T - Tz) / (C - Tz))

[0119] 2. If T < Tz (i.e. net cell killing), cell survival is defined as

[0120] % Cell survival=100 ■ ((T - Tz) / Tz)

[0121] GI50 is finally used as reference value (Table 1). Results presented here were obtained with the analysis of at least three independent experiments (n) each of them performed in triplicate for each of the compound in every tumor cell line, except for 22Rv1 and NCI-H660 where only a duplicate was obtained. Dose-response curves for PM534 in each cell line assayed are shown in Figures 1-19. PM534 compound showed a dose-dependence potency in vitro in the different cell lines in the low nanomolar range.Table 1. Antiproliferative effect (GI50) of PM534 in a panel of cell lines representative of prostate, gastric, sarcoma and small-cell lung human tumors.

[0122] Tissue Cell line GI5o(M) (n) Prostate 22Rv1 2.14E-09 2

[0123] LNCap 3.04E-09 3

[0124] NCI-H660 1.87E-09 2

[0125] PC-3 1.67E-09 4 VCap 2.72E-09 4 Gastric AGS 2.00E-09 4

[0126] CLS-145 3.36E-09 4

[0127] NCI-N87 1.14E-09 4

[0128] HGC-27 2.16E-09 5 Hs746t 1.42E-09 4 Sarcoma A673 2.23E-09 4

[0129] HT-1080 2.17E-09 3

[0130] MES-SA 2.33E-09 3

[0131] RD-ES 2.74E-09 4

[0132] SK-NEP-1 1.88E-09 3 SW872 2.29E-09 3

[0133] TC-32 1.95E-09 5

[0134] TC-71 2.99E-09 3

[0135] Lung-SCLC DMS-53 2.30E-09 3

[0136]

[0137] Cell cycle, flow cytometry and Immunofluorescence assay

[0138] 22Rv1 prostate cancer cells were seeded at 60-70% confluency. After 24 hours, cells were treated with PM534 or vehicle. Following a 24-hour treatment, cells were incubated with 10 pM 5-BrdU (MedchemExpress, HY-15910) for 1 hour at 37°C. Cells were then trypsinized, centrifuged, and resuspended in PBS containing LIVE / DEAD™ Fixable Near-IR (ThermoFisher, L10119) following the manufacturer’s protocol. After 20 minutes at 4°C, cells were centrifuged and fixed in 300 pL ethanol at -20°C overnight. Cells were centrifuged and rehydrated in PBS for 15 minutes. DNA denaturation was achieved with 2M HCI for 20 minutes, followed by neutralization in 0.1 M Na2B4O? for 10 minutes. Cells were washed, incubated with anti-BrdU antibody (Biolegend, Clone 3D4), and washed again. Finally, cells were resuspended in PBS with 0.1% Triton X-100, 50 pg / mL RNase (ThermoFisher, EN0531), and 20 pg / mL propidium iodide (ThermoFisher, P3566) for 1 hour at 37°C. Cell cycle analysis was performed on a Cytoflex S cytometer (Beckman Coulter).For the immunofluorescence assay, cells were treated with PM534 for 24 h, fixed with 4% paraformaldehyde, permeabilized and incubated with a blocking solution (5% bovine serum albumin in PBS) for 30 min. Cells were then incubated with primary mouse anti-human a-tubulin antibody for 1 h at room temperature. After three washes with a PBS / BSA1% solution, cells were incubated with Alexa Fluor 488-conjugated goat anti-mouse IgG secondary antibody at room temperature for 1 h. Preparations were counterstained with Hoechst 33342, labelling DNA, and mounted with Mowiol mounting medium. Pictures were taken with a Leica 157 DM I RM fluorescence microscope equipped with a 100 oil immersion objective and a DFC 340 FX digital camera (Leica, Wetzlar, Germany).

[0139] EXAMPLE 2: In vivo assays of PM534 in xenograft murine models

[0140] All animal protocols were reviewed and approved according to regional Institutional Animal Care and Use Committees (IACUC).

[0141] Design, randomization and monitoring of experiments (including body weights and tumor measurements) were performed through NewLab Software v2.25.06.00 (NewLab Oncology, France).

[0142] Athymic Nude-Foxn1nu / nu (both genders) and CB17 / lcr-Prkc / csc / c / (male) mice (Envigo RMS B.V., Limburg, Netherlands) between 4 and 6 weeks of age were housed in individually ventilated cages on a 12-h light-dark cycle at 21-23°C and 40-60% humidity. Mice were allowed free access to an irradiated diet and sterilized water.

[0143] 2.1 Unilateral subcutaneous transplantation of patient tumor tissue

[0144] Mice were injected into their right flank with ca. 5 106cells suspended in 0.05 mL of a solution consisting of 50% Matrigel (Corning Inc., USA) and 50% cell culture medium, without serum or antibiotics. Male athymic Nude-Foxn1nu / nu and male CB17 / \cr-Prkdcscid were xenografted with 22Rv1 and VCaP tumors, respectively.

[0145] When tumors reached ca. 150 mm3, mice (n>6 mice / group) were randomly allocated (Day 0) to receive PM534 or placebo. PM534 doses were selected based on the previously calculated maximum tolerated dose (MTD), that were determined to be from 5.0 and 2.5 mg / kg. Mice bearing H526 and H82 xenografted tumors were treated at 2.5 mg / kg (1 / 2MTD) and 3.6 mg / kg (3 / 4MTD) of PM534 respectively, while xenografted mice with the other tumors received the full MTD (Tables 2 to 9 and Figures 24-31).

[0146] Intravenous treatments consisted of a weekly administration for 2 consecutive weeks (HT-1080, H82) or 3 consecutive weeks (VCaP, 22RV1, HGC-27, H526, Hs746t, H660). In each experiment, control animals received an equal volume of placebo with the same schedule.Caliper measurements of the tumor diameters were performed 2 to 3 times a week, and tumor volumes were calculated according to the following formula: volume =(a b2) / 2, where a and b presented the longest and shortest tumor diameters, respectively. For survival evaluation, the euthanasia endpoint was either a tumor volume larger than 2,000 mm3, tumor necrosis, or both. Complete tumor regression (CR) was defined as tumor volume <63 mm3for 2 or more consecutive measurements, such value corresponding to the lowest measurable limit considering the contribution of the skin, mass from fibrous material, and so on.

[0147] Statistical differences in animal survival were assessed by Kaplan-Meier curves using the log-rank test. Post-treatment tumor volume data were analyzed using a non-parametric, two-tailed Mann-Whitney ( / -test. Data are presented as medians and IQR or mean±SD.

[0148] Table 2. Tumour volume evaluation in xenograft murine model intravenously injected with H660 prostate cancer cell line with the compound of the present invention PM534 at dose of 3.75 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 24).

[0149] Days Median tumour volume (mm3)

[0150] Placebo PM534

[0151] 0 239.1 184.6

[0152] 4 241.9 184.6

[0153] 7 359.7 178.9

[0154] 10 451.2 162.5

[0155] 14 584.3 151.3

[0156] 18 643.3 176.2

[0157] 21 828.5 219.1

[0158] 25 1073.3 383.3

[0159] 28 1518.6 504.8

[0160] 32 - 876.2

[0161] 35 - 1117.6

[0162] 39 - 1188.0

[0163] 42 - 1555.4

[0164]

[0165] Table 3. Tumour volume evaluation in xenograft murine model intravenously injected with VCap prostate cancer cell line with the compound of the present invention PM534 at dose of 2.5 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 25).

[0166] Days Median tumour volume (mm3)

[0167] Placebo PM534

[0168] 0 159.5 158.4

[0169] 3 230.8 155.9

[0170] 7 382.6 174.0

[0171] 10 479.6 197.2

[0172] 14 614.2 235.5

[0173] 17 811.1 241.9

[0174] 21 981.8 316.8

[0175] 24 1107.9 344.5

[0176] 28 1372.0 488.7

[0177] 31 1393.4 559.8

[0178] 35 1510.1 550.0

[0179] 38 - 886.2

[0180] 42 - 1080.0

[0181] 45 - 1120.0

[0182] 49 - 1512.3

[0183]

[0184] Table 4. Tumour volume evaluation in xenograft murine model intravenously injected with 22Rv1 prostate cancer cell line with the compound of the present invention PM534 at dose of 3.75 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 26).

[0185] Days Median tumour volume (mm3)

[0186] Placebo PM534

[0187] 0 179.0 165.2

[0188] 2 233.5 175.2

[0189] 4 436.3 171.1

[0190]

[0191] 7 647.2 208.8

[0192] 9 863.3 239.7

[0193] 11 1135.1 272.0

[0194] 14 1510.1 299.6

[0195] 16 - 260.1

[0196] 18 - 339.2

[0197] 21 - 679.0

[0198] 23 - 1033.8

[0199] 25 - 1520.1

[0200]

[0201] Table 5. Tumour volume evaluation in xenograft murine model intravenously injected with HGC-27 gastric cancer cell line with the compound of the present invention PM534 at dose of 5 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 27).

[0202] Days Median tumour volume (mm3)

[0203] Placebo PM534

[0204] 0 191.9 191

[0205] 3 421.2 221.2

[0206] 5 663.8 258.2

[0207] 7 897.5 364.8

[0208] 10 1251.1 396.2

[0209] 12 1517.3 566.3

[0210] 14 1867.5 680.8

[0211] 17 2025 786.1

[0212] 19 - 1042.5

[0213] 21 - 1284.4

[0214] 24 - 2027.7

[0215]

[0216] Table 6. Tumour volume evaluation in xenograft murine model injected with Hs746t gastric cancer cell line with the compound of the present invention PM534 at dose of 5 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 28).

[0217] Days Median tumour volume (mm3)

[0218] Placebo PM534

[0219] 0 184 185

[0220] 4 465.5 158.4

[0221] 7 683.5 176.4

[0222] 11 987.7 145.1

[0223] 14 1312.5 153.5

[0224] 18 1345.2 166.3

[0225] 21 1491.7 221.7

[0226] 25 - 621.6

[0227] 28 - 1061.1

[0228] 32 - 1444.9

[0229] 35 - 1618.7

[0230]

[0231] Table 7. Tumour volume evaluation in xenograft murine model injected with HT-1080 sarcoma cell line with the compound of the present invention PM534 at dose of 5 mg / kg by weekly administration for 2 consecutive weeks (data shown in Figure 29).

[0232] Days Median tumour volume (mm3)

[0233] Placebo PM534

[0234] 0 7.9 7.9

[0235] 2 11.3 9.8

[0236] 4 12.2 8.3

[0237] 7 13.9 8.1

[0238] 9 15.0 8.5

[0239] 11 16.4 9.0

[0240] 14 18.0 10.6

[0241]

[0242] 16 - 13.2

[0243] 18 - 14.5

[0244] 21 - 15.3

[0245] 24 - 16.4

[0246] 28 - 17.2

[0247]

[0248] Table 8. Tumour volume evaluation in xenograft murine model injected with H82 small-cell lung cancer cell line with the compound of the present invention PM534 at dose of 3.56 mg / kg by weekly administration for 2 consecutive weeks (3 / 4 MTD) (data shown in Figure 30).

[0249] Days Median tumour volume (mm3)

[0250] Placebo PM534

[0251] 0 194.5 177.1

[0252] 2 383.5 187.7

[0253] 4 512.5 181.0

[0254] 7 682.2 141.2

[0255] 9 937.0 130.5

[0256] 11 1210.4 133.3

[0257] 14 1513.8 160.2

[0258] 16 - 236.4

[0259] 18 - 287.6

[0260] 21 - 517.7

[0261] 23 - 760.9

[0262] 25 - 950.8

[0263] 28 - 1134.7

[0264] 30 - 1317.6

[0265] 32 - 1524.2

[0266]

[0267] Table 9. Tumour volume evaluation in xenograft murine model injected with H526 small-cell lung cancer cell line with the compound of the present invention PM534 at dose of 2.5 mg / kg by weekly administration for 3 consecutive weeks (1 / 2 MTD) (data shown in Figure 31).Days Median tumour volume (mm3)

[0268] Placebo PM534

[0269] 0 178.6 183.8

[0270] 3 331.3 173.9

[0271] 5 580.4 139.9

[0272] 7 884.8 152.7

[0273] 10 - 149.3

[0274] 12 1179.6 186.0

[0275] 14 1528.8 264.3

[0276] 17 1713.2 356.9

[0277] 19 - 448.0

[0278] 21 - 620.6

[0279] 24 - 892.8

[0280] 26 - 1185.5

[0281] 28 - 1502.0

[0282]

[0283] 2.2. Bilateral subcutaneous transplantation of patient tumor tissue

[0284] In the case of in vivo LMS and DDLPS xenograft murine models, xenografts were established by bilateral subcutaneous transplantation of patient tumour tissue in 6-7-week-old female, partially immunodeficient NMRI nu / nu mice (Janvier Laboratories). All patients underwent surgery in the Department of Surgical Oncology or Orthopedic Surgery, University Hospitals Leuven (Belgium) and gave a written informed consent for using the tissue to create patient-derived xenograft (PDX) models and the use of these models in preclinical research projects. The establishment of PDX models was also approved by the Medical Ethics Committee of the University Hospitals Leuven and by the KU Leuven Ethics Committee for Animal Research.

[0285] The in vivo efficacy of PM534 was evaluated using two leiomyosarcoma (UZLX-STS149 and -STS22) models and a dedifferentiated liposarcoma (UZLX-STS112) PDXs. For cohort expansion of each model, 36 mice were implanted subcutaneously on both left and right flank with the model under general anaesthesia.Pre-study tumour volumes were measured weekly, until tumours reached an average tumour volume of approximately 150mm3, then 32 mice were randomized into 4 treatment groups (7 to 9 mice per group), as described in Table 10.

[0286] Table 10. Treatment applied with placebo or PM534 to LMS and DDLPS murine xenografts

[0287] Concentration working Group Treatment Schedule Dose solution A1 (n=4) Control (PM534 placebo) Q7Dx3 i.v. 5ml / kg 0.95 mg / ml A2 (n=4) Control (PM534 placebo) Q7Dx3 i.v. 5ml / kg 0.95 mg / ml D1 (n=4) PM534 Q7Dx3 i.v. 4.75 mg / kg 0.95 mg / ml

[0288]

[0289] D2 (n=4) PM534 Q7Dx3 i.v. 4.75 mg / kg 0.95 mg / ml

[0290] The drug was administered on a weekly administration for 3 consecutive weeks through intravenous tail vein injection. All abnormal injections were recorded, nothing was reported if abnormalities with injections did not occur.

[0291] Tumors were measured three times each week in three dimensions (Length, Width, Height) under isoflurane anaesthesia, and tumour volume (V) calculated as V= ir / 6 x L x W x H. Animals were weighed three times each week. General wellbeing of animals was monitored daily, and all observations were recorded (Tables 11 to 13).

[0292] Each individual mouse was followed until its tumor exceeds 2000 mm3, or showed severe signs of toxicity (e.g. decrease in body weight to <80% of the starting value) or up until a maximum of 16 days, whichever was first. Mice were sacrificed by pentobarbital overdose and cervical dislocation. Gross necropsy was performed, and abnormal findings were recorded. Tumours were collected and cut in half, one half was fixed in formalin and subsequently embedded in paraffin to obtain formalin fixed paraffin-embedded (FFPE) blocks. The other half of the tumour sample was cut in smaller fragments and snap-frozen in liquid nitrogen and stored at -80°C.

[0293] Table 11. Tumor volume evaluation in xenograft murine model injected with STS149 leiomyosarcoma cell line with the compound of the present invention PM534 at dose of 4.75 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 36). 1 murine model treated with placebo was sacrificed on Day 13. 3 murine models treated with PM534 were sacrificed between Day 9 and Day 10 due to weight loss or a tumor volume higher than 2000 mm3.Days Median tumour volume (mm3)

[0294] Placebo PM534

[0295] 1 176.7 201.8

[0296] 5 463.2 268.3

[0297] 7 461.1 279.7

[0298] 9 723.9 240.9

[0299] 12 1054.8 264.8

[0300] 14 1133.2 318.8

[0301] 16 1228.3 372.4

[0302]

[0303] Table 12. Tumour volume evaluation in xenograft murine model injected with STS22 leiomyosarcoma cell line with the compound of the present invention PM534 at dose of 4.75 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 37). 1 murine model treated with placebo was sacrificed on Day 13.

[0304] Days Median tumour volume (mm3)

[0305] Placebo PM534

[0306] 1 153.0 92.6

[0307] 2 104.3 76.4

[0308] 6 206.3 118.3

[0309] 8 202.6 118.0

[0310] 10 271.8 131.7

[0311] 13 242.2 141.4

[0312] 15 235.9 118.1

[0313] 16 316.3 103.3

[0314]

[0315] Table 13. Tumour volume evaluation in xenograft murine model injected with STS112 dedifferentiated liposarcoma cell line with the compound of the present invention PM534 at dose of 4.75 mg / kg by weekly administration for 3 consecutive weeks (data shown in Figure 38).

[0316] 2 murine model treated with placebo was sacrificed on Day 7 and 1 was sacrificed on Day 11 due to a tumor volume higher than 2000 mm3.Days Median tumour volume (mm3)

[0317] Placebo PM534

[0318] 1 210.9 171.6

[0319] 3 257.9 202.3

[0320] 6 418.1 218.3

[0321] 8 284.2 238.4

[0322] 10 329.1 241.6

[0323] 13 443.4 268.9

[0324] 15 559.6 287.6

[0325] 16 558.2 251,6

[0326]

[0327] Results

[0328] The in vitro antitumor activity of PM534 was evaluated in a panel of nineteen tumor cell lines representing four different human tumors: prostate cancer, small-cell lung cancer, gastric cancer and sarcoma. The results demonstrated very strong PM534-mediated in vitro antitumor activity, the mean GI50 being 2.17 nM, with values ranging from 1.14 nM (NCI-N87 gastric) to 3.36 nM (CLS-145; gastric).

[0329] Cell cycle and immunofluorescence assay demonstrated that after 24 hours of treatment with PM534 at 10nM, a pronounced accumulation of cells in the G2 / M phase was recorded, being the percentage of cell population in this phase (versus control) of 53.1% (versus 26.1%) in 22Rv1 prostate cancer cells. These findings are in agreement with the effect on the cell cycle mediated by a disruptor of tubulin polymerization (Figure 20). Moreover, a-tubulin immunofluorescence revealed multinucleated and divided cells 24 hours post-treatment with PM534 (Figure 21).

[0330] These data clearly demonstrate that PM534 exhibits potent antitumor activity across a diverse panel of human cancer cell lines, inducing irreversible effects that result in G2 / M cell cycle arrest and multinucleation.

[0331] Furthermore, in vivo antitumor activity of PM534 was evaluated in a panel of eight unilateral transplanted xenografts including representative prostate (H660, VCaP, and 22RV1), gastric (HGC-27, HS746t), sarcoma (HT-1080) and small-cell lung cancer (H526 and H82) tumors.In this panel, tumor-bearing mice were administered with PM534 once per week for two or three consecutive weeks (dose levels of 2.5 and 5 mg / kg). In the population of treated mice, no PM534-related mortality was recorded.

[0332] Moreover, in vivo activity was evaluated in a panel of three bilateral transplanted xenografts including STS149 and STS22 leiomyosarcoma cancer and ST112 dedifferentiated liposarcoma tumours. In this panel, tumor-bearing mice were administered with PM534 once per week for three consecutive weeks (dose level of 4.75 mg / kg).

[0333] In vivo antitumor activity was assessed in each xenograft (unilateral transplantation) by tumor volume on the last day, with 100% of the live population in the placebo-treated group (inlets Figures 22A to 22H). Regardless of the type of tumor, a very highly statistically significant antitumor activity was recorded after PM534 administration. Thus, median tumor volume reductions (compared to placebo) were recorded in mice HC-660 (219.1 mm3vs. 828.5 mm3on Day 21), VCap (344.5 mm3vs. 1 ,107.9 333 mm3on Day 24), 22Rv1 (208.8 mm3vs. 647.2 mm3on Day 7), HGC-27 (566.3 mm3vs. 1517.3 mm3on Day 12), Hs746t (176.4 mm3vs. 683.5 mm3on Day 7), HT-1080 (10.6 mm3vs. 18 mm3on Day 14), H82 (236.4 mm3vs. sacrificed mice on Day 16), H526 (264.3 mm3vs. 1528.8 mm3on Day 14) xenograft tumors.

[0334] This tumor reduction resulted in statistically significant increases in the median survival time of tumor-bearing mice treated with PM534 vs. placebo (Figures 22A to 22H).

[0335] In the bilateral transplanted xenografts, antitumor activity was assessed by tumor volume (Tables 11 to 13 and Figures 36 to 38). In the STS149 leiomyosarcoma, STS22 leiomyosarcoma, and ST112 dedifferentiated liposarcoma tumor models, treatment with PM534 led to tumor volume stabilization and tumor growth delay. In the STS149 leiomyosarcoma model, the treated group showed growth of 185% vs 695% for placebo on day 16. In the STS22 leiomyosarcoma model, the treated group showed growth of 112% vs 207% for placebo on day 16. In the ST112 dedifferentiated liposarcoma model, the treated group showed growth of 147% vs 265% for placebo on day 16. The antitumor effect in all three models was significantly better than in vehicle-treated mice.

[0336] PM534 was shown to be well tolerated with no severe signs of toxicity (e.g. decrease in body weight to <80% of the starting value). Figures 33 to 35 show PM534 was well tolerated throughout the experiment at the dose administered.

[0337] In conclusion, PM534 markedly reduces tumor volume and extends survival across diverse xenograft models with no severe toxicity reported.Moreover, after administration of PM534 (at 2.5 or 5 mg / kg) to xenografted mice, prostate tumors (22Rv1 and VCaP) were obtained at 168 hours after treatment (24 hours after a second dose of PM534).

[0338] Results demonstrated a statistically significant increase (versus placebo) in the number of apoptotic cells after PM534 treatment. Specifically, apoptotic nuclei (mean±SD) were 4.0±0.7 vs. 2.2±1.1 (p=0.0397) in VCaP and 33.8±11.2 vs. 3.6±2.4 (p=0.0079) in 22Rv1 tumors (Figure 23). Additionally, a marked increase in the percentage of necrosis (compared to placebo) was observed in 22Rv1 tumors at 95% vs. 45% (harvested 24 hours after the second dose of PM534). However, the same level of necrosis was not seen in VCap tumor. This is probably due to the time on which the tumor was extracted. In fact, it is believed that it was undertaken too early to note a marked percentage of necrosis.

[0339] PM534 significantly increases apoptosis, mitotic catastrophe, and necrosis in multiple xenograft tumors, underscoring its potent antitumor effects.References

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Claims

CLAIMS1. PM534for use in the treatment of solid tumours selected from prostate cancer, gastric cancer, sarcoma and small cell lung cancer.

2. PM534 for use according to claim 1 , wherein the solid tumour is prostate cancer.

3. PM534 for use according to claim 2, wherein the prostate cancer is neuroendocrine prostate cancer, adenocarcinoma prostate cancer or carcinoma prostate cancer.

4. PM534 for use according to claim 1 , wherein the solid tumour is gastric cancer.

5. PM534 for use according to claim 4, wherein the gastric cancer is stomach adenocarcinoma, gastroesophageal junction adenocarcinoma, gastrointestinal neuroendocrine tumors, gastrointestinal stromal tumors and primary gastric lymphoma.

6. PM534 for use according to claim 4, wherein the gastric cancer is carcinoma gastric cancer or adenocarcinoma gastric cancer.

7. PM534 for use according to claim 1 , wherein the solid tumour is sarcoma.

8. PM534 for use according to claim 7, wherein the sarcoma is soft tissue sarcoma, bone sarcoma, cic-rearranged sarcoma, Ewing sarcoma, fibrosarcoma, uterine sarcoma, liposarcoma (LPS), leiomyosarcoma (LMS) or dedifferentiated liposarcoma (DDLPS).

9. PM534 for use according to claim 1 , wherein the solid tumour is small cell lung cancer.

10. PM534 for use according to claim 9, wherein the small cell lung cancer is extensive stage small cell lung cancer or limited stage small cell lung cancer.

11. PM534 for use according to any one of claims 1 to 10, wherein PM534 is in the form of a pharmaceutically acceptable salt or ester thereof.

12. A pharmaceutical composition comprising PM534, for use in the treatment of cancer according to any one of claims 1 to 11.

13. A dosage form comprising PM534 for use in the treatment of cancer according to any one of claims 1 to 11.

14. A kit comprising a therapeutically effective amount of compound PM534 and a pharmaceutically acceptable carrier for use in the treatment of cancer according to any one of claims 1 to 11.

Images