Adenosine derivatives for use in the treatment of cancer

Abstract

The present invention relates to adenosine derivatives for use in cancer therapies, and particularly although not exclusively, to hormone-dependent cancer therapies, for example methods for treating, preventing or ameliorating prostate or breast cancer. Additionally, the present invention relates to methods for treating, preventing or ameliorating pancreatic cancer. The invention also extends to esters of Aspartyl-adenylate and to their use in therapy.

Description

[0001]Cancer Therapy The present invention relates to cancer therapies, and particularly although not exclusively, to hormone-dependent cancer therapies, for example, methods for treating, preventing or ameliorating prostate or breast cancer. Additionally, the present invention relates to methods for treating, preventing or ameliorating pancreatic cancer. The invention also extends to novel compositions of matter, and to their use in therapy. Prostate cancer (PCa) is one of the leading causes of cancer-related deaths in men worldwide, with over 1.4 million new cases diagnosed in the year 2020. The androgen receptor (AR) signalling axis has a critical role not only in the development and maintenance of male sex characteristics but also as a key regulator of the PCa development and its progression to castration-resistant prostate cancer (CRPC). Therefore, the standard of care treatment functions by directly targeting androgens or the AR signalling axis using androgen deprivation therapy (ADT). However, the failure of ADT and the subsequent development of CRPC, where targeted therapeutic options are very limited and mostly palliative, pose a major challenge for patients and healthcare systems around the world. The progression of PCa disease is characterised by abnormally increased AR activity which could result from the dysregulation of AR-associated factors (AR-AFs). AR- AFs, which display a diverse range of functions and are involved in multiple cellular pathways, interact with different domains of AR to modulate gene expression through a series of coordinated molecular events in different cellular compartments. Playing such an important role in controlling and driving AR transcriptional activity has enhanced interest in AR-AFs and their use as alternative new targets to block AR action in PCa and CRPC. Aminoacyl-tRNA synthetases (AARSs) are a family of enzymes that catalyse the covalent ligation of each of the twenty amino acids to their corresponding tRNA during the first stage of protein synthesis. Considered one of the ancient families of proteins, AARSs have evolved and adapted through time incorporating additional motifs and domains to participate in many types of protein-protein interactions and carry out diverse roles in the cells in addition to their canonical role in protein synthesis. Elucidation of emerging non-canonical functions of AARSs and their indispensable role in human diseases like central neuro-system disorders, inflammatory disorders, and cancer development and progression, have brought to light their potential as disease biomarkers and novel therapeutic targets. However, the role of AARSs in cancer is still not well understood. In view of the above, there is still an unmet urgent need to provide treatments for patients suffering from prostate cancer, and in particular, incurable CRPC, who do not respond to currently available therapies. Accordingly, in a first aspect of the invention, there is provided an inhibitor of an aminoacyl-tRNA synthetase (AARS), for use in treating, preventing or ameliorating cancer. In a second aspect of the invention, there is provided a method of treating, preventing or ameliorating cancer in a subject, the method comprising administering, or having administered, to a subject in need of such treatment, a therapeutically effective amount of an inhibitor of an aminoacyl-tRNA synthetase (AARS). As described in the Examples, the inventors have unexpectedly discovered that the androgen receptor (AR), which is predominantly a nuclear protein, interacts with the components of protein synthesis machinery, i.e. aminoacyl-tRNA synthetases (AARSs), which usually reside in the cytosol. They are the first to have observed this surprising bimolecular interaction, which therefore suggests a novel, non- canonical function of AARSs in regulating an oncogenic transcription factor. Additionally, the inventors have identified that AARS, such as the DARS enzyme (i.e. Aspartyl-tRNA synthetase) and the IARS enzyme (Isoleucyl-tRNA synthetase), drive AR activity in prostate cancer. From these unexpected observations, the inventors have demonstrated that the catalytic inhibition of DARS and / or IARS (e.g. by an analogue of Aspartyl-adenylate, Asp-AMS, or Ile-AMS), or the siRNA- mediated depletion of DARS and / or IARS, degrades AR and its highly oncogenic variant in hormone-resistant prostate cancer cells. In particular, the inventors have demonstrated that Asp-AMS triggers apoptosis in prostate cancer cells, and is superior to the current treatment Enzalutamide, in its growth repression of prostate cancer. The inventors have further demonstrated in tumour xenograft-bearing mouse models that Asp-AMS(OMe) and / or Ile-AMS, significantly control the growth of prostate, pancreatic and breast cancer tumours, promote apoptosis in prostate, pancreatic and breast cancer cells, and reduce the proliferation of tumour cells. Aminoacyl-tRNA synthetases (AARS), otherwise known as tRNA ligases, are a family of enzymes that catalyse the covalent ligation of cognate amino acids to their corresponding tRNA during the first stage of protein synthesis. In a preferred embodiment, the aminoacyl-tRNA synthetase (AARS), is Aspartyl tRNA-synthetase (DARS) or Isoleucyl tRNA-synthetase (IARS). Most preferably, the aminoacyl-tRNA synthetase (AARS) is Aspartyl tRNA- synthetase (DARS). In another preferred embodiment, the aminoacyl-tRNA synthetase (AARS) is Isoleucyl tRNA-synthetase (IARS). DARS ligates L-aspartate to tRNA(Asp) and is encoded by the gene, DARS1. In one embodiment, the nucleotide sequence encoding DARS1 is provided as GenBank ID No: NM_001349.2. In one embodiment, DARS may comprise an amino acid sequence of SEQ ID No: 2, which is provided herein, as follows: TSTSQAVFRLQSGICHLFRETLINKGFVEIQTPKIISAASEGGANVFTVSYFKNNAYLAQSPQLYKQMCI CADFEKVFSIGPVFRAEDSNTHRHLTEFVGLDIEMAFNYHYHEVMEEIADTMVQIFKGLQERFQTEIQTV NKQFPCEPFKFLEPTLRLEYCEALAMLREAGVEMGDEDDLSTPNEKLLGHLVKEKYDTDFYILDKYPLAV RPFYTMPDPRNPKQSNSYDMFMRGEEILSGAQRIHDPQLLTERALHHGIDLEKIKAYIDSFRFGAPPHAG GGIGLERVTMLFLGLHNVRQTSMFPRDPKRLTP [SEQ ID No: 2] Accordingly, in a preferred embodiment, DARS comprises or consists of an amino acid sequence substantially as set out in SEQ ID No: 2, or a fragment or variant thereof. In another preferred embodiment, the aminoacyl-tRNA synthetase (AARS) is Isoleucyl tRNA-synthetase (IARS). IARS ligates isoleucine to tRNA(Asp) and is encoded by the gene, IARS1. In one embodiment, the nucleotide sequence encoding IARS1 is provided as GenBank ID No: 3376. In one embodiment, IARS may comprise an amino acid sequence of SEQ ID No: 3, which is provided herein, as follows: QNLKVLIDPVSVQDKDTLSIHYLMLPRVREELIDKKTESAVSQMQSVIELGRVIRDRKTIPIKYPLKEIV VIHQDPEALKDIKSLEKYIIEELNVRKVTLSTDKNKYGIRLRAEPDHMVLGKRLKGAFKAVMTSIKQLSS EELEQFQKTGTIVVEGHELHDEDIRLMYTFDQATGGTAQFEAHSDAQALVLLDVTPDQSMVDEGMAREVI NRIQKLRKKCNLVPTDEITVYYKAKSEGTYLNSVIESHTEFIFTTIKAPLKPYPVSPSDKVLIQEKTQLK GSELEITLTRGSSLPGPACAYVNLNICANGSEQGGVLLLENPKGDNRLDLLKLKSVVTSIFGVKNTELAV FHDETEIQNQTDLLSLSGKTLCVTAGSAPSLINSSSTLLCQYINLQLLNAKPQECLMGTVGTLLLENPLG QNGLTHQGLLYEAAKVFGLRSRKLKLFLNETQTQEITEDIPVKTLNMKTVYVSVLPTTAD [SEQ ID No: 3] Accordingly, in a preferred embodiment, IARS comprises or consists of an amino acid sequence substantially as set out in SEQ ID No: 3, or a fragment or variant thereof. In a preferred embodiment, the inhibitor is a small molecule. Preferably, the inhibitor or small molecule is configured to inhibit an aminoacyl- tRNA synthetase (AARS). Preferably, the AARS is Aspartyl tRNA-synthetase (DARS) or Isoleucyl tRNA-synthetase (IARS). Most preferably, however, the inhibitor or small molecule is configured to inhibit DARS. Alternatively, in another preferred embodiment, the inhibitor or small molecule is configured to inhibit IARS. Preferably, the inhibitor is an analogue of Aspartyl-adenylate. Aspartyl-adenylate (N(6)-(1,2-dicarboxyethyl)-AMP) is the N(6)-(1,2-dicarboxyethyl) derivative of adenosine 5’-monophosphate. Most preferably, the inhibitor is 5’-O-[N-(L-Aspartyl)sulfamoyl]adenosine (Asp- AMS), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof. Asp-AMS is an analogue of Aspartyl-adenylate. Preferably, Asp-AMS has the formula C14H19N7O9S. Preferably, Asp-AMS has the formula (I): (I). In another embodiment, the inhibitor is an ester of Asp-AMS, or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof. For example, suitable esters of Asp-AMS have the formula (IV): a C6-C12 aryl. The term ” as used herein, unless otherwise specified, refers to a saturated straight or branched hydrocarbon. In certain embodiments, the alkyl group is a primary, secondary, or tertiary hydrocarbon. In certain embodiments, the alkyl group includes one to six carbon atoms, i.e. C1-C6 alkyl. C1-C6 alkyl includes for example methyl, ethyl, n-propyl (1-propyl) and isopropyl (2-propyl, 1-methylethyl), butyl, pentyl, hexyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl and isohexyl. “Aryl” refers to an aromatic 6 to 12 membered hydrocarbon group. The term includes bicyclic groups where one of the rings is aromatic and the other is not. It may be appreciated that in aryl groups all of the ring atoms are carbon. Examples of a C6-C12 aryl group include, but are not limited to, phenyl, α-naphthyl, β- naphthyl, biphenyl, tetrahydronaphthyl and indanyl. In an embodiment, R1is a C3 alkyl. In another embodiment, R1is a C2 alkyl. In a typical embodiment, R1is a C1 alkyl. Accordingly, the inhibitor may comprise Asp- AMS(OMe). Thus, in another embodiment, the inhibitor is Asp-AMS(OMe), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof. Preferably, Asp-AMS(OMe) has the formula C15H21N7O9S. Preferably, Asp-AMS(OMe) has the formula (II): (II). In another embodiment, R1is a C1-C6 alkyl substituted with a C6-C12 aryl. The alkyl may be a C1-C3 alkyl. In an embodiment, the alky l m ay be a C3 alkyl. In another embodiment, the alkyl may be a C2 alkyl. In a particular embodiment, the alkyl is methyl. The aryl may be phenyl. Accordingly, the inhibitor may comprise Asp- AMS(OBn). Thus, in another embodiment, the inhibitor is Asp-AMS(OBn), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof. In an embodiment, Asp-AMS(OBn) has the formula (V): . are Asp-AMS(OMe) and Asp-AMS(OBn) Therefore, in another aspect, there is provided a compound of formula (IVa), a C6-C12 aryl, or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof. In a further aspect, there is provided a compound of formula (IV) or (IVa), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof, for use as a medicament. In a further aspect, there is provided a compound of formula (IV) or (IVa), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof, for use in treating, preventing or ameliorating cancer. In a further aspect of the invention, there is provided a method of treating, preventing or ameliorating cancer in a subject, the method comprising administering, or having administered, to a subject in need of such treatment, a therapeutically effective amount of a compound comprising formula (IV) or (IVa), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof. In another aspect of the invention, there is provided a pharmaceutical composition comprising a therapeutically effective amount of a compound comprising formula (IV) or (IVa), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof, and a pharmaceutically acceptable vehicle. In another preferred embodiment, the inhibitor is an analogue of Isoleucyl - adenylate. Preferably, the inhibitor is Ile-AMS, or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof. Ile-AMS is an analogue of 5’-O-[N-(L- Isoleucyl)-sulfamoyl]adenylate. Preferably, Ile-AMS has the formula C16H25N7O7S. Preferably, Ile-AMS has the formula (III): . to refer to any salt of a carbohydrate provided herein which retains its biological properties and which is not toxic or otherwise undesirable for pharmaceutical use. Such salts may be derived from a variety of organic and inorganic counter-ions well known in the art. Such salts include, but are not limited to: (1) acid addition salts formed with organic or inorganic acids such as hydrochloric, hydrobromic, sulfuric, nitric, phosphoric, sulfamic, acetic, adepic, aspartic, trifluoroacetic, trichloroacetic, propionic, hexanoic, cyclopentylpropionic, glycolic, glutaric, pyruvic, lactic, malonic, succinic, sorbic, ascorbic, malic, maleic, fumaric, tartaric, citric, benzoic, 3-(4- hydroxybenzoyl)benzoic, picric, cinnamic, mandelic, phthalic, lauric, methanesulfonic, ethanesulfonic, 1,2-ethane-disulfonic, 2-hydroxyethanesulfonic, benzenesulfonic, 4-chlorobenzenesulfonic, 2-naphthalenesulfonic, 4-toluenesulfonic, camphoric, camphorsulfonic, 4-methylbicyclo[2.2.2]-oct-2-ene-1-carboxylic, glucoheptonic, 3-phenylpropionic, trimethylacetic, tert-butylacetic, lauryl sulfuric, gluconic, benzoic, glutamic, hydroxynaphthoic, salicylic, stearic, cyclohexylsulfamic, quinic, muconic acid and the like acids; or (2) base addition salts formed when an acidic proton present in the parent compound either (a) is replaced by a metal ion, e.g., an alkali metal ion, an alkaline earth ion or an aluminium ion, or alkali metal or alkaline earth metal hydroxides, such as sodium, potassium, calcium, magnesium, aluminium, lithium, zinc, and barium hydroxide, ammonia or (b) coordinates with an organic base, such as aliphatic, alicyclic, or aromatic organic amines, such as ammonia, methylamine, dimethylamine, diethylamine, picoline, ethanolamine, diethanolamine, triethanolamine, ethylenediamine, lysine, arginine, ornithine, choline, N,N′-dibenzylethylene-diamine, chloroprocaine, diethanolamine, procaine, N-benzylphenethylamine, N-methylglucamine piperazine, tris(hydroxymethyl)-aminomethane, tetramethylammonium hydroxide, and the like. Pharmaceutically acceptable salts may include, sodium, potassium, calcium, magnesium, ammonium, tetraalkylammonium and the like, and when the compound contains a basic functionality, salts of non-toxic organic or inorganic acids, such as hydrohalides, e.g. hydrochloride, hydrobromide and hydroiodide, carbonate or bicarbonate, sulfate or bisulfate, borate, phosphate, hydrogen phosphate, dihydrogen phosphate, pyroglutamate, saccharate, stearate, sulfamate, nitrate, orotate, oxalate, palmitate, pamoate, acetate, trifluoroacetate, trichloroacetate, propionate, hexanoate, cyclopentylpropionate, glycolate, glutarate, pyruvate, lactate, malonate, succinate, tannate, tartrate, tosylate, sorbate, ascorbate, malate, maleate, fumarate, tartarate, camsylate, citrate, cyclamate, benzoate, isethionate, esylate, formate, 3-(4-hydroxybenzoyl)benzoate, picrate, cinnamate, mandelate, phthalate, laurate, methanesulfonate (mesylate), methylsulphate, naphthylate, 2-napsylate, nicotinate, ethanesulfonate, 1,2-ethane- disulfonate, 2-hydroxyethanesulfonate, benzenesulfonate (besylate), 4- chlorobenzenesulfonate, 2-naphthalenesulfonate, 4-toluenesulfonate, camphorate, camphorsulfonate, 4-methylbicyclo[2.2.2]-oct-2-ene-1-carboxylate, glucoheptonate, 3-phenylpropionate, trimethylacetate, tert-butylacetate, lauryl sulfate, gluceptate, gluconate, glucoronate, hexafluorophosphate, hibenzate, benzoate, glutamate, hydroxynaphthoate, salicylate, stearate, cyclohexylsulfamate, quinate, muconate, xinofoate and the like. Hemisalts of acids and bases may also be formed, for example, hemisulphate salts. The skilled person will appreciate that the aforementioned salts include ones wherein the counterion is optically active, for example, D-lactate, or racemic, for example, DL-tartrate. The term “solvate” may be understood to refer to a compound provided herein or a salt thereof, that further includes a stoichiometric or non-stoichiometric amount of solvent bound by non-covalent intermolecular forces. Where the solvent is water, the solvate is a hydrate. Pharmaceutically acceptable solvates in accordance with the invention include those wherein the solvent of crystallization may be isotopically substituted, e.g. D2O, d6-acetone and d6-DMSO. In another preferred embodiment, the inhibitor is an interfering nucleic acid molecule. Preferably the inhibitor or interfering nucleic acid molecule is configured to inhibit an aminoacyl-tRNA synthetase (AARS). Preferably, the AARS is Aspartyl tRNA- synthetase (DARS) or Isoleucyl tRNA-synthetase (IARS). Most preferably, however, the inhibitor or interfering nucleic acid molecule is configured to inhibit DARS. Alternatively, in another preferred embodiment, the inhibitor or interfering nucleic acid molecule is configured to inhibit IARS. The interfering nucleic acid molecule may include antisense oligonucleotide, siRNA, or dsRNA, which specifically targets the gene encoding an aminoacyl-tRNA synthetase (AARS). A functional interfering nucleic acid molecule, including antisense oligonucleotides, siRNA molecules, or dsRNA molecules, is capable of specifically downregulating a target gene, preferably one or more exons thereof. Accordingly, in a preferred embodiment, the inhibitor is RNAi. The RNAi may be microRNA (miRNA), small interfering RNA (siRNA) or short hairpin RNA (shRNA). Most preferably, the inhibitor is siRNA. In one embodiment, when the aminoacyl-tRNA synthetase (AARS) is Aspartyl tRNA- synthetase (DARS), preferably the siRNA comprises the nucleic acid sequence of SEQ ID No: 1 (Gene Accession: NM_001349), which is provided herein as follows: GAUCUUAGGACAUCAACUA [SEQ ID No: 1] Accordingly, in a preferred embodiment, the siRNA comprises a nucleic acid sequence as set out in SEQ ID No: 1, or a fragment or variant thereof. In one embodiment, the cancer is a hormone-dependent cancer. Accordingly, in another aspect of the invention, there is provided an inhibitor of an aminoacyl-tRNA synthetase (AARS), for use in treating, preventing or ameliorating a hormone-dependent cancer. In another aspect of the invention, there is provided a method of treating, preventing or ameliorating a hormone-dependent cancer in a subject, the method comprising administering, or having administered, to a subject in need of such treatment, a therapeutically effective amount of an inhibitor of an aminoacyl-tRNA synthetase (AARS). The term “hormone-dependent cancer” (or “hormone-sensitive cancer”) as used herein, will be understood to mean a cancer that is dependent on a hormone for growth and / or survival. The hormone-dependent cancer may be steroid hormone-driven cancer, an androgen-dependent cancer, an oestrogen-dependent cancer, or a progesterone- dependent cancer. Preferably, the androgen-dependent cancer is prostate cancer. Preferably, the oestrogen-dependent cancer is selected from a group consisting of: breast cancer, ovarian cancer, and endometrial (uterine) cancer. Preferably, the progesterone-dependent cancer is selected from a group consisting of: breast cancer and endometrial (uterine) cancer. Most preferably, the hormone-dependent cancer is prostate cancer. The prostate cancer may be castration-resistant prostate cancer, or AR-driven or androgen receptor positive aggressive form of prostate cancer. Alternatively, the hormone-dependent cancer may be breast cancer. Accordingly, it will be appreciated that in a most preferred embodiment, there is provided an inhibitor of Aspartyl tRNA-synthetase (DARS), for use in treating prostate cancer, wherein the inhibitor is siRNA or Asp-AMS or Asp-AMS(OMe). Most preferably, the cancer is castration-resistant prostate cancer. Alternatively, in another embodiment, there is provided an inhibitor of Aspartyl tRNA-synthetase (DARS), for use in treating prostate cancer, wherein the inhibitor is Ile-AMS. Typically, the cancer is castration-resistant prostate cancer. Alternatively, in another embodiment, there is provided an inhibitor of Aspartyl tRNA-synthetase (DARS), for use in treating breast cancer, wherein the inhibitor is siRNA or Asp-AMS or Asp-AMS(OMe). Alternatively, in another embodiment, there is provided an inhibitor of Aspartyl tRNA-synthetase (DARS), for use in treating breast cancer, wherein the inhibitor is Ile-AMS. Alternatively, in another embodiment, the cancer is pancreatic cancer. Accordingly, in one embodiment, there is provided an inhibitor of Aspartyl tRNA- synthetase (DARS), for use in treating pancreatic cancer, wherein the inhibitor is siRNA or Asp-AMS or Asp-AMS(OMe). Alternatively, in another embodiment, there is provided an inhibitor of Aspartyl tRNA-synthetase (DARS), for use in treating pancreatic cancer, wherein the inhibitor is Asp-AMS(OMe). As discussed in Examples 8-12, treatment with Asp-AMS(OMe) significantly controlled the growth of castrate-resistant 22Rv1 tumours, C4-2B tumours and BxPC-3 pancreatic tumours, compared to vehicle controls. Accordingly, in one embodiment, the inhibitor controls and represses the growth of tumours. In one embodiment, the inhibitor controls and represses the growth of prostate tumours, such as castrate-resistant tumours. In one embodiment, the inhibitor controls and represses the growth of breast tumours. In one embodiment, the inhibitor controls and represses the growth of pancreatic tumours. Additionally, both Asp-AMS(OMe) and Ile-AMS increased CC-3 levels indicating the promotion of apoptosis / cell death. Accordingly, in one embodiment, the inhibitor promotes apoptosis of cancer and / or tumour cells. Additionally, as shown in Example 8 and Figure 20, both Asp-AMS(OMe) and Ile- AMS reduced proliferation of tumour cells in vivo. Accordingly, in one embodiment, the inhibitor reduces the proliferation of cancer and / or tumour cells in vivo. It will be appreciated that the inhibitor of an aminoacyl-tRNA synthetase (AARS) according to the invention may be used in a medicament, which may be used as a monotherapy (i.e. use of the inhibitor of an AARS alone), for treating, preventing or ameliorating cancer, such as a hormone-dependent cancer, or pancreatic cancer, in a subject. Alternatively, the inhibitor of an AARS according to the invention may be used as an adjunct to, or in combination with, known therapies for treating, preventing or ameliorating cancer, such as a hormone-dependent cancer, or pancreatic cancer, in a subject. For example, the subject may be additionally treated with surgery, radiotherapy, and / or chemotherapy. The inhibitor of an aminoacyl-tRNA synthetase (AARS) according to the invention may be combined in compositions having a number of different forms depending, in particular, on the manner in which the composition is to be used. Thus, for example, the composition may be in the form of a powder, tablet, capsule, liquid, ointment, cream, gel, hydrogel, aerosol, spray, micellar solution, transdermal patch, liposome suspension or any other suitable form that may be administered to a person or animal in need of treatment. It will be appreciated that the vehicle of medicaments according to the invention should be one which is well-tolerated by the subject to whom it is given. Medicaments comprising the inhibitor of an aminoacyl-tRNA synthetase (AARS) according to the invention may be used in a number of ways. For instance, oral administration may be required, in which case the inhibitor of an AARS may be contained within a composition that may, for example, be ingested orally in the form of a tablet, capsule or liquid. The inhibitor of an AARS of the invention may be formulated with a cell membrane permeability enhancer, penetration enhancer and / or absorption enhancer. The inhibitor of an aminoacyl-tRNA synthetase (AARS) according to the invention may also be incorporated within a slow- or delayed-release device. Such devices may, for example, be inserted on or under the skin, and the medicament may be released over weeks or even months. The device may be located adjacent the treatment site. Such devices may be particularly advantageous when long-term treatment with the inhibitor of an AARS used according to the invention is required and which would normally require frequent administration (e.g. daily injection). In a preferred embodiment, medicaments according to the invention may be administered to a subject by injection into the blood stream or directly into a site requiring treatment. For example, the medicament may be injected close to, or at least adjacent to the pancreatic islets. Injections may be intravenous (bolus or infusion), intramuscular (bolus or infusion), subcutaneous (bolus or infusion), or intradermal (bolus or infusion). It will be appreciated that the amount of the inhibitor of an aminoacyl-tRNA synthetase (AARS) that is required is determined by its biological activity and bioavailability, which in turn depends on the mode of administration, the physiochemical properties of the peptide and whether it is being used as a monotherapy or in a combined therapy. The frequency of administration will also be influenced by the half-life of the inhibitor of an AARS within or on the subject being treated. Optimal dosages to be administered may be determined by those skilled in the art, and will vary with the particular inhibitor of an AARS in use, the strength of the pharmaceutical composition, and the mode of administration. Additional factors depending on the particular subject being treated will result in a need to adjust dosages, including subject age, weight, gender, diet, and time of administration. Optimal dosages may be determined depending on the severity of the cancer. The inhibitor of an aminoacyl-tRNA synthetase (AARS) may be administered once or twice a day for infected subjects who are hospitalised. Infected subjects who are not hospitalised may require less frequent administration of the inhibitor of an AARS, such as once or twice a week, and / or lower doses than hospitalised subjects. Alternatively, the inhibitor of an AARS may be administered even less frequently when being used as a prophylactic treatment. For example, weekly or monthly administration of the inhibitor of an AARS may be required for uninfected subjects with pre-existing disease conditions which contribute to the severity of cancer. Generally, a daily dose of between 0.001µg / kg of body weight and 10 mg / kg of body weight, or between 0.01 ^g / kg of body weight and 1 mg / kg of body weight, of the inhibitor of an aminoacyl-tRNA synthetase (AARS) according to the invention may be used for treating, preventing or ameliorating cancer, such as a hormone- dependent cancer, in a subject. The inhibitor of an aminoacyl-tRNA synthetase (AARS) may be administered before, during or after onset of symptoms associated with cancer. Daily doses may be given as a single administration (e.g. a single daily application). Alternatively, the inhibitor of an AARS may require administration twice or more times during a day. As an example, the inhibitor of an AARS may be administered as two (or more) daily doses of between 0.07 ^g and 700 mg (i.e. assuming a body weight of 70 kg). A patient receiving treatment may take a first dose upon waking and then a second dose in the evening (if on a two dose regime) or at 3- or 4-hourly intervals thereafter. Alternatively, a slow release device may be used to provide optimal doses of the inhibitor of an AARS according to the invention to a patient without the need to administer repeated doses. Known procedures, such as those conventionally employed by the pharmaceutical industry (e.g. in vivo experimentation, clinical trials, etc.), may be used to form specific formulations of the inhibitor of an aminoacyl-tRNA synthetase (AARS) according to the invention and precise therapeutic regimes (such as daily doses of the agents and the frequency of administration). The inventors believe that they are the first to suggest a cancer treatment composition, such as a hormone- dependent cancer treatment composition, based on the use of the inhibitor of an aminoacyl-tRNA synthetase (AARS) of the invention. Hence, in a third aspect of the invention, there is provided a cancer prevention, treatment or amelioration pharmaceutical composition comprising a therapeutically effective amount of an inhibitor of an aminoacyl-tRNA synthetase (AARS), and a pharmaceutically acceptable vehicle. The invention also provides in a fourth aspect, a process for making the cancer prevention, treatment or amelioration pharmaceutical composition according to the third aspect, the process comprising combining a therapeutically effective amount of the inhibitor of an aminoacyl-tRNA synthetase (AARS), with a pharmaceutically acceptable vehicle. In one embodiment, the composition according to the third and fourth aspect is a hormone-dependent cancer prevention, treatment or amelioration pharmaceutical composition. Accordingly, in another aspect of the invention, there is provided a hormone- dependent cancer prevention, treatment or amelioration pharmaceutical composition comprising a therapeutically effective amount of an inhibitor of an aminoacyl-tRNA synthetase (AARS), and a pharmaceutically acceptable vehicle. The invention also provides in another aspect, a process for making the hormone- dependent cancer prevention, treatment or amelioration pharmaceutical composition, the process comprising combining a therapeutically effective amount of the inhibitor of an aminoacyl-tRNA synthetase (AARS), with a pharmaceutically acceptable vehicle. Alternatively, in another embodiment, the composition according to the third and fourth aspect is a pancreatic cancer prevention, treatment or amelioration pharmaceutical composition. A “subject” may be a vertebrate, mammal, or domestic animal. Hence, medicaments according to the invention may be used to treat any mammal, for example livestock (e.g. a horse), pets, or may be used in other veterinary applications. Most preferably, however, the subject is a human being. A “therapeutically effective amount” of an inhibitor of an aminoacyl-tRNA synthetase (AARS) is any amount which, when administered to a subject, is the amount of active agent that is needed to treat, ameliorate, or prevent the cancer, or produce the desired effect. The inhibitor of an AARS may be used as an adjuvant for the prevention or treatment of a cancer. This means that lower doses of other prophylactic or therapeutic treatments would be required. For example, the therapeutically effective amount of inhibitor of an aminoacyl-tRNA synthetase (AARS) used may be from about 0.001 mg to about 800 mg, and preferably from about 0.01 mg to about 500 mg. A “pharmaceutically acceptable vehicle” as referred to herein, is any known compound or combination of known compounds that are known to those skilled in the art to be useful in formulating pharmaceutical compositions. In one embodiment, the pharmaceutically acceptable vehicle may be a solid, and the composition may be in the form of a powder or tablet. A solid pharmaceutically acceptable vehicle may include one or more substances which may also act as flavouring agents, lubricants, solubilisers, suspending agents, dyes, fillers, glidants, compression aids, inert binders, sweeteners, preservatives, coatings, or tablet- disintegrating agents. The vehicle may also be an encapsulating material. In powders, the vehicle is a finely divided solid that is in admixture with the finely divided active agents according to the invention. In tablets, the active agent (i.e. the peptide or nucleic acid) may be mixed with a vehicle having the necessary compression properties in suitable proportions and compacted in the shape and size desired. Suitable solid vehicles include, for example calcium phosphate, magnesium stearate, talc, sugars, lactose, dextrin, starch, gelatin, cellulose, polyvinylpyrrolidine, low melting waxes and ion exchange resins. In another embodiment, the pharmaceutical vehicle may be a gel and the composition may be in the form of a cream or the like. However, the pharmaceutical vehicle may be a liquid, and the pharmaceutical composition is in the form of a solution. Liquid vehicles are used in preparing solutions, suspensions, emulsions, syrups, elixirs and pressurized compositions. The active agent according to the invention (i.e. the peptide or nucleic acid) may be dissolved or suspended in a pharmaceutically acceptable liquid vehicle such as water, an organic solvent, a mixture of both or pharmaceutically acceptable oils or fats. The liquid vehicle can contain other suitable pharmaceutical additives such as solubilisers, emulsifiers, buffers, preservatives, sweeteners, flavouring agents, suspending agents, thickening agents, colours, viscosity regulators, stabilizers or osmo-regulators. Suitable examples of liquid vehicles for oral and parenteral administration include water (partially containing additives as above, e.g. cellulose derivatives, preferably sodium carboxymethyl cellulose solution), alcohols (including monohydric alcohols and polyhydric alcohols, e.g. glycols) and their derivatives, and oils (e.g. fractionated coconut oil and arachis oil). For parenteral administration, the vehicle can also be an oily ester such as ethyl oleate and isopropyl myristate. Sterile liquid vehicles are useful in sterile liquid form compositions for parenteral administration. The liquid vehicle for pressurized compositions can be a halogenated hydrocarbon or other pharmaceutically acceptable propellant. Liquid pharmaceutical compositions, which are sterile solutions or suspensions, can be utilized by, for example, intramuscular, intrathecal, epidural, intraperitoneal, intravenous and particularly subcutaneous injection. The inhibitor of an aminoacyl- tRNA synthetase (AARS) may be prepared as a sterile solid composition that may be dissolved or suspended at the time of administration using sterile water, saline, or other appropriate sterile injectable medium. The inhibitor of an aminoacyl-tRNA synthetase (AARS) and compositions of the invention may be administered orally in the form of a sterile solution or suspension containing other solutes or suspending agents (for example, enough saline or glucose to make the solution isotonic), bile salts, acacia, gelatin, sorbitan monoleate, polysorbate 80 (oleate esters of sorbitol and its anhydrides copolymerized with ethylene oxide) and the like. The inhibitor of an AARS used according to the invention can also be administered orally either in liquid or solid composition form. Compositions suitable for oral administration include solid forms, such as pills, capsules, granules, tablets, and powders, and liquid forms, such as solutions, syrups, elixirs, and suspensions. Preferably, orally administrable formulations do not dissolve in the stomach, but preferentially dissolve in the duodenum. Orally administrable formulations may be enterically-coated, for example, enteric-coated tablets or capsules. Forms useful for parenteral administration include sterile solutions, emulsions, and suspensions. It will be appreciated that the invention extends to any nucleic acid or peptide or variant, derivative or analogue thereof, which comprises substantially the amino acid or nucleic acid sequences of any of the sequences referred to herein, including variants or fragments thereof. The terms “substantially the amino acid / nucleotide / peptide sequence”, “variant” and “fragment”, can be a sequence that has at least 40% sequence identity with the amino acid / nucleotide / peptide sequences of any one of the sequences referred to herein, for example 40% identity with any of the sequence identified herein. Amino acid / polynucleotide / polypeptide sequences with a sequence identity which is greater than 65%, more preferably greater than 70%, even more preferably greater than 75%, and still more preferably greater than 80% sequence identity to any of the sequences referred to are also envisaged. Preferably, the amino acid / polynucleotide / polypeptide sequence has at least 85% identity with any of the sequences referred to, more preferably at least 90% identity, even more preferably at least 92% identity, even more preferably at least 95% identity, even more preferably at least 97% identity, even more preferably at least 98% identity and, most preferably at least 99% identity with any of the sequences referred to herein. The skilled technician will appreciate how to calculate the percentage identity between two amino acid / polynucleotide / polypeptide sequences. In order to calculate the percentage identity between two amino acid / polynucleotide / polypeptide sequences, an alignment of the two sequences must first be prepared, followed by calculation of the sequence identity value. The percentage identity for two sequences may take different values depending on:- (i) the method used to align the sequences, for example, ClustalW, BLAST, FASTA, Smith-Waterman (implemented in different programs), or structural alignment from 3D comparison; and (ii) the parameters used by the alignment method, for example, local vs global alignment, the pair-score matrix used (e.g. BLOSUM62, PAM250, Gonnet etc.), and gap-penalty, e.g. functional form and constants. Having made the alignment, there are many different ways of calculating percentage identity between the two sequences. For example, one may divide the number of identities by: (i) the length of shortest sequence; (ii) the length of alignment; (iii) the mean length of sequence; (iv) the number of non-gap positions; or (v) the number of equivalenced positions excluding overhangs. Furthermore, it will be appreciated that percentage identity is also strongly length dependent. Therefore, the shorter a pair of sequences is, the higher the sequence identity one may expect to occur by chance. Hence, it will be appreciated that the accurate alignment of protein or DNA sequences is a complex process. The popular multiple alignment program ClustalW (Thompson et al., 1994, Nucleic Acids Research, 22, 4673-4680; Thompson et al., 1997, Nucleic Acids Research, 24, 4876-4882) is a preferred way for generating multiple alignments of proteins or DNA in accordance with the invention. Suitable parameters for ClustalW may be as follows: For DNA alignments: Gap Open Penalty = 15.0, Gap Extension Penalty = 6.66, and Matrix = Identity. For protein alignments: Gap Open Penalty = 10.0, Gap Extension Penalty = 0.2, and Matrix = Gonnet. For DNA and Protein alignments: ENDGAP = -1, and GAPDIST = 4. Those skilled in the art will be aware that it may be necessary to vary these and other parameters for optimal sequence alignment. Preferably, calculation of percentage identities between two amino acid / polynucleotide / polypeptide sequences may then be calculated from such an alignment as (N / T)*100, where N is the number of positions at which the sequences share an identical residue, and T is the total number of positions compared including gaps and either including or excluding overhangs. Preferably, overhangs are included in the calculation. Hence, the most preferred method for calculating percentage identity between two sequences comprises (i) preparing a sequence alignment using the ClustalW program using a suitable set of parameters, for example, as set out above; and (ii) inserting the values of N and T into the following formula:- Sequence Identity = (N / T)*100. Alternative methods for identifying similar sequences will be known to those skilled in the art. For example, a substantially similar nucleotide sequence will be encoded by a sequence which hybridizes to DNA sequences or their complements under stringent conditions. By stringent conditions, the inventors mean the nucleotide hybridises to filter-bound DNA or RNA in 3x sodium chloride / sodium citrate (SSC) at approximately 45ºC followed by at least one wash in 0.2x SSC / 0.1% SDS at approximately 20-65ºC. Alternatively, a substantially similar polypeptide may differ by at least 1, but less than 5, 10, 20, 50 or 100 amino acids from any of the sequences described herein. Due to the degeneracy of the genetic code, it is clear that any nucleic acid sequence described herein could be varied or changed without substantially affecting the sequence of the protein encoded thereby, to provide a functional variant thereof. Suitable nucleotide variants are those having a sequence altered by the substitution of different codons that encode the same amino acid within the sequence, thus producing a silent (synonymous) change. Other suitable variants are those having homologous nucleotide sequences but comprising all, or portions of, sequence, which are altered by the substitution of different codons that encode an amino acid with a side chain of similar biophysical properties to the amino acid it substitutes, to produce a conservative change. For example, small non-polar, hydrophobic amino acids include glycine, alanine, leucine, isoleucine, valine, proline, and methionine. Large non-polar, hydrophobic amino acids include phenylalanine, tryptophan and tyrosine. The polar neutral amino acids include serine, threonine, cysteine, asparagine and glutamine. The positively charged (basic) amino acids include lysine, arginine and histidine. The negatively charged (acidic) amino acids include aspartic acid and glutamic acid. It will therefore be appreciated which amino acids may be replaced with an amino acid having similar biophysical properties, and the skilled technician will know the nucleotide sequences encoding these amino acids. All of the features described herein (including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined with any of the above aspects in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying Figures, in which:- Figure 1 shows androgen receptor (AR) qPLEX-RIME (Quantitative Rapid Immunoprecipitation Mass Spectrometry of Endogenous Proteins) under androgenic and enzalutamide conditions. (A) AR peptide sequence coverage and number of unique peptides identified in the AR qPLEX-RIME. (B) Volcano plot summarising the enrichment of proteins binding to AR under androgenic or enzalutamide conditions from the quantitative results obtained from the AR qPLEX-RIME in C4-2B cells. Changes in AR complex after 2 hours of 1μM enzalutamide treatment were observed. For each condition four biological replicates were used per AR-RIME matched with three negative controls IgG-RIME. Figure 2 shows the validation of Aspartyl tRNA-synthetase (DARS) physical interaction with AR in C4-2B and 22Rv1 PCa cell lines. Western blot of AR and DARS protein levels of (A) Forward co-IP pulling down AR performed in C4-2B cells growing in complete media. (B) Reverse co-IP pulling down DARS performed in C4- 2B cells growing in complete media. (C) Same as (A) except that in 22Rv1 cells. (D) Same as (B) except that in 22Rv1. IgG negative control was used in all co-IPs and a 1% input was run as positive control in each Western blot. AR means full length androgen receptor (AR-FL) in all cases. Figure 3 demonstrates that DARS silencing reduces cell viability in prostate epithelial cell lines including PCa cell lines. Cell viability assay in RWPE-1, C4-2B, 22Rv1, R1-AD1 and R1-D567 after siRNA-mediated DARS and AR knockdown assessed by MTS assay at five days post-transfection. The percentage of cell viability is relative to non-targeting scramble siRNA (siScr). Results represent mean ± SEM (n=3 biological replicates). *= p<0.033, **= p<0.002, ***= p<0.001. Figure 4 illustrates that DARS knockdown reduces AR transcriptional activity as measured by the expression of three AR-target gene (ARTGs) expression in PCa cell lines LNCaP, C4-2B, and 22Rv1. Relative gene expression of AR target genes (ARTGs), KLK3, TMPRSS2 and NKX3.1, assessed by RT-qPCR in (A) LNCaP, (B) C4- 2B, and (C) 22Rv1 PCa cells growing in complete media and treated with siRNA- mediated knockdown of AR and DARS (SiRNA concentration was 10 nM). Cells were harvested at 72 hours post-transfection. Non-targeting scramble negative control (siScr) was used. Results represent mean ± SEM of gene expression enrichment relative to negative control siScr. AR means AR-FL in all cases. (n=3 biological replicates), *= p<0.033, **= p<0.002, ***= p<0.001. Figure 5 shows that DARS gene expression is regulated by AR in LNCaP, C4-2b and 22Rv1 PCa cells. Relative gene expression of AR, DARS and ARTGs assessed in PCa cells treated with siRNA-mediated knockdown of AR and DARS (10 nM siRNA used for transfection). Cells were harvested at 72 hours post-transfection and gene expression of AR and DARS were assessed by RT-qPCR. (A) LNCaP, (B) C4-2B cells showed a reduction of DARS gene expression after AR depletion (C) 22Rv1 showed a reduction of DARS gene expression after AR depletion as well as a reduction of AR and AR-V7 gene expression after DARS silencing. Non-targeting scramble negative control (siScr) was used in all cases for data normalisation. (D) LNCaP and (E) C4- 2B cells treated with 1nM of synthetic androgen R1881 for 48 hours showing an increase of DARS gene expression. (F) 22Rv1 cells treated with 1nM of synthetic androgen R1881 for 48 hours showed no changes in DARS gene expression after androgen stimulation. Results represent mean ± SEM of gene expression enrichment relative to negative control siScr or Vehicle. AR means AR-FL in all cases. (n=3 biological replicates), *= p<0.033, **= p<0.002, ***= p<0.001. Figure 6 illustrates the effect of Asp-AMS (an analogue of Aspartyl-adenylate) in PCa cell lines. The relative confluence of LNCaP, C4-2B and 22RV1 cell lines were assessed using the Incucyte® SX5 Live-Cell Analysis System. Cells growing in complete media were treated for five days with increasing concentrations of Asp- AMS up to 4 μM and with 10μM Enzalutamide as positive control. (A) LNCaP cells were shown to be less sensitive to Asp-AMS than Enzalutamide. (B) C4-2B cells showed that concentrations of Asp-AMS higher than 2.5 μM repressed cell growth more effectively than 10 μM Enzalutamide. (C) 22Rv1 cells were shown to be more sensitive to Asp-AMS than 10μM Enzalutamide. Relative confluence was calculated in relation to confluency at 0 hours. (n=2 biological replicates), *= p<0.033, **= p<0.002, ***= p<0.001. Figure 7 shows a flow cytometry analysis of Asp-AMS induction of apoptosis in PCa cell lines. FACS plots showing dual staining of Annexin and 7-AAD in LNCaP, C4-2B, and 22RV1 cells treated with increasing doses of Asp-AMS up to 10 μM in combination with / without 1nM of synthetic androgen R1881 for 72 hours. (A) LNCaP cells reduced the number of apoptotic cells induced by 10 μM Asp-AMS by 26% when co-treated with androgens. (B) C4-2B cells reduced the number of apoptotic cells induced by 10 μM Asp-AMS by 11% when co-treated with androgens. (C) 22Rv1 cells did not show any reduction of the number of apoptotic cells when co-treated with androgens. FACS plot images are representative of two biological replicates. (D), (E) and (F) represent the percentage of apoptotic cells of (A), (B) and (C). FACS plots are representative of two biological replicates. Data is represented as mean ± SEM of duplicate experiments (n=2 biological replicates), *= p<0.033, **= p<0.002, ***= p<0.001. Figure 8 shows the effect of direct DARS inhibition on AR protein levels and subcellular localisation. Western blots showing AR and DARS total protein levels and subcellular localisation in PCa cell lines, LNCaP, C4-2B and 22Rv1, treated with Asp- AMS for 72 hours prior to be harvested and sample processed. Whole-cell lysate (WcL) and cytosolic and nuclear fractions were evaluated by western blotting. (A) LNCaP cells treated with 2.5 μM Asp-AMS showed no effect on AR and DARS protein levels or subcellular localisation. (B) C4-2B cells treated with 2.5 μM Asp-AMS showed no effect on AR and DARS protein levels but a slight decrease on AR nuclear levels was observed after treatment. (C) 22Rv1 cells treated with 2 μM Asp- AMS showed a strong decrease in AR and AR-Vs protein levels, as well as DARS protein levels reflected on cytoplasmic and nuclear fractions. β-Actin was used as loading control and H3 was used as nuclear fraction marker. (D), (E) and (F) show densitometry of (A), (B) and (C) normalised to β-actin. Note that the DARS second band detected in whole-cell lysate and cytoplasmic fraction belongs to mitochondrial DARS (DARS2), which serves as internal cytoplasmic marker of cell fractionation. AR means AR-FL in all cases. (n=2 biological replicates), *= p<0.033, **= p<0.002, ***= p<0.001. Figure 9 shows the effect of direct DARS inhibition on AR and ARTG gene expression and transcriptional activity. Relative gene expression of AR, ARTGs and DARS assessed by RT-qPCR in PCa cell lines treated with Asp-AMS alone or in combination with 1 nM of synthetic androgen R1881. (A) LNCaP cells treated with 2.5 μM of Asp-AMS showed no effect on AR gene expression or on the androgen- induced ARTGs expression. (B) C4-2B cells treated with 2.5 μM Asp-AMS showed no effect on AR gene expression. Androgen-induced expression of KLK3 and DARSs was slightly decreased by Asp-AMS treatment. (C) 22RV1 cells were strongly affected by treatment with 2 μM of Asp-AMS reducing AR and AR-V7 gene expression and therefore ARTGs expression. Results represent mean ± SEM of gene expression enrichment relative to the negative control Vehicle. AR means AR-FL in all cases. (n=3 biological replicates), *= p<0.033, **= p<0.002, ***= p<0.001. Figure 10 shows that AR physically interacts with IARS. Western blot of AR and IARS protein levels after co-IP pulling down IARS performed in prostate cancer (C4- 2B) cell lysates treated with 100 μg / ml of RNase A for 15 minutes at 37°C. IgG was used as IP negative control and a 1% input was used as Western blot positive control. Note that to be able to degrade tRNA with RNaseA a low NaCl concentration was used in the lysates (< 0.1 M). Figure 11 shows that IARS depletion reduces AR and AR-V7 transcripts expression in prostate cancer (PCa) cell lines C4-2B and 22Rv1. The results show the relative gene expression of AR assessed by qRT-PCR in C4-2B (A) along with the relative gene expression of AR and AR-v7 in 22Rv1 (B and C). Cells were grown in RPMI 1640 media and transfected with siRNA targeting IARS (10 nM). Cells were harvested 72 hours post-transfection, mRNA was isolated, and qRT-PCR was conducted. Non-targeting scramble negative control (siScr) was used. siRNA targeting the AR (siAR) was used as a positive control. Results represent mean +- SEM of gene expression enrichment relative to negative control. (n=3 biological replicates) AR represents AR full-length in all cases. Figure 12 illustrates that IARS depletion reduces AR protein levels. (A) Western blot analysis of AR and AR-V7 / 9 protein levels following siRNA mediated silencing of eight AARSs (siDARS, siEPRS, siHARS, siIARS, siQARS, siRARS and siVARS) in 22Rv1 PCa cell lines. (B) Western blot analysis of AR, AR-V7 / 9 and IARS protein levels in the nucleus and cytosol of C4-2B and 22Rv1 PCa cell lines following siRNA mediated depletion on IARS. β-actin and histone H3 were used as a loading control. Figure 13 shows AARSs knockdown effects on three ARTGs transcript expression in C4-2B and 22Rv1 cell lines. C4-2B (A) and 22Rv1 (B) cell lines were treated with an individual siRNA (10 nM) targeting eight different AARSs (siDARS, siEPRS, siHARS, siIARS, siIARS2, siQARS, siRARS and siVARS) or a non-targeting scramble siRNA control (siScr). siAR was used as a positive control. Cells were harvested at 72 hours post-transfection and ARTGs (KLK3, TMPRSS2 and NKX3.1) expression was assessed by RT-qPCR. Results represent mean ± SEM of enrichment relative to the negative control (n=3 biological replicates).90 *= p<0.033, **= p<0.002, ***= p<0.001. Figure 14 illustrates that IARS inhibitor Iso-AMS alters gene expression of AR and AR target genes. Relative gene expression of AR-FL, KLK3 and NKX3.1 transcripts assessed in C4-2B cells treated with either DMSO, Iso-AMS or Enzalutamide with or without synthetic androgen R1881 (1nM). Cells were harvested 24 hours post- treatment and the gene expression of AR-FL, KLK3 and NKX3.1 were assessed by RT-qPCR. (A) C4-2B cells showed a reduction in AR-FL gene expression when treated with Iso-AMS. (B) C4-2B cells showed a reduction in the AR-TG KLK3 gene expression when treated with Iso-AMS. (C) C4-2B cells showed a reduction in the AR-TG NKX3.1 gene expression when treated with Iso-AMS. The data was normalised to GAPDH. Figure 15 illustrates that Iso-AMS IC50 in PCa cell lines is linked to androgen responsiveness. LNCaP and C4-2B PCa cells were treated with increasing doses of Iso-AMS alone or in combinatorial treatment with 1 nM of synthetic androgen R1881. Cell viability of the cells was assessed by MTS assay at five days of treatment. (A) LNCaP cell viability profile and IC50 values showed a higher degree of resistance to Iso-AMS treatment when combined with androgens. (B) LNCaP cell viability profile and IC50 values showed a higher degree of resistance to Enzalutamide when combined with androgens than that was seen in LNCaP cell with Iso-AMS drug treatment. (C) C4-2B cell viability profile and IC50 values showed a slight degree of resistance to Iso-AMS treatment when combined with androgens. (D) C4-2B cell viability profile and IC50 values showed a higher degree of resistance to Enzalutamide induced by combination with androgens treatment compared to that seen in C4-2B cells with Iso-AMS drug treatment. (E) 22Rv1 cell viability profile and IC50 values showed higher degree of resistance to Iso-AMS treatment when combined with androgens. (F) 22Rv1 cell viability profile and IC50 values showed a higher degree of resistance to Enzalutamide when combined with androgens than that seen in LNCaP cell with Iso-AMS drug treatment. The IC50 values were determined using GraphPad Prism 8.4.3. Plotted values represent mean ± SEM of two biological replicates (n=3 biological replicates). Figure 16 shows that Iso-AMS alters the protein expression of the AR. Western blot of C4-2B cells treated with DMSO control, Enzalutamide or Iso-AMS - / + 1nM synthetic androgen R1881. Cells were harvested 24 hours post-treatment. Treatment with Iso-AMS reduced both AR and IARS levels in the whole cell lysate. Densitometry analysis of Western blot analysis is shown below the Western blot. The data was normalised to β-actin. AR represents AR full length in all cases. Figure 17 shows that Iso-AMS is safe to use in animals. Three male Balb / c nude mice were given 10 mgs / kg Iso-AMS once daily (oral dosing) for 14 days and body weights were measured daily. Average daily weight changes are shown. Figure 18 shows the volume of 22Rv1 prostate tumours on male Balb / c nude mice, following daily treatment with Enzalutamide at 10 mg / kg or Asp-AMS-(OMe) at 5 mg / kg compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 19 shows the volume of 22Rv1 prostate tumours on male Balb / c nude mice, following daily treatment with Enzalutamide at 10 mg / kg or Isoleucyl-AMS (Ile- AMS) at 5 mg / kg compared to vehicle control (vehicle and Enzalutamide arms duplicated; same as in Figure 18). Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 20 shows immunohistochemical analysis of apoptotic (CC-3) and proliferation markers (Ki67) in excised 22Rv1 tumour xenografts following treatment with Asp-AMS(OMe) or Ile-AMS. CC-3 levels were quantified in tumours to determine tumour apoptotic index following oral administration of Enzalutamide, Asp-AMS(OMe) and Ile-AMS to tumour-bearing mice (A, B). The H-score was calculated by quantifying the levels of proliferation marker Ki67 following oral administration of Enzalutamide, Asp-AMS(OMe) and Ile-AMS to tumour-bearing mice (C, D). Statistical significance was calculated using a one-way ANOVA test for all treatment groups. (vehicle and Enzalutamide arms duplicated in Figures B and D from A and C) Figure 21 shows the normalised bodyweight of male Balb / c nude mice bearing 22Rv1 tumours following daily treatment with Enzalutamide at 10 mg / kg, Asp-AMS- (OMe) at 5 mg / kg compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 22 shows the normalised bodyweight of male Balb / c nude mice bearing 22Rv1 tumours following daily treatment with Enzalutamide at 10 mg / kg, Ile-AMS at 5 mg / kg compared to vehicle control (vehicle and Enzalutamide arms duplicated; same as in Figure 21). Values shown are mean ±SEM; initially n=8 for all treatment groups. Figure 23 shows the volume of C4-2B prostate tumours on male Balb / c nude mice, following daily treatment with Enzalutamide at 10 mg / kg or Asp-AMS-(OMe) at 5 mg / kg compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 24 shows the volume of C4-2B prostate tumour xenograft in male Balb / c nude mice, following daily (QD) treatment with Enzalutamide at 10 mg / kg or Isoleucyl-AMS at 5 mg / kg compared to vehicle control (vehicle and Enzalutamide arms duplicated; same as in Figure 23). Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one- way ANOVA test. Figure 25 shows apoptotic (CC-3) and proliferation markers (Ki67) in tumours following treatment with Asp-AMS(OMe) or Ile-AMS. CC-3 levels were quantified in tumours to determine tumour apoptotic index following oral administration of Enzalutamide, Asp-AMS(OMe) and Ile-AMS to C4-2B prostate tumour-bearing mice (A, B). The H-score was calculated by quantifying the levels of proliferation marker Ki67 following oral administration of Enzalutamide, Asp-AMS(OMe) and Ile-AMS to tumour-bearing mice (C, D). Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 26 shows the normalised body weight of male Balb / c nude mice bearing C4- 2B prostate tumours following daily treatment with Enzalutamide at 10 mg / kg, Asp- AMS-(OMe) at 5 mg / kg compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 27 shows the normalised body weight of male Balb / c nude mice bearing C4- 2B prostate tumours following daily treatment with Enzalutamide at 10 mg / kg, Ile- AMS at 5 mg / kg compared to vehicle control. (vehicle and Enzalutamide arms duplicated; same as in Figure 26) Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 28 shows the volume of MCF-7 breast tumours on female NXG mice, following daily treatment with tamoxifen at 4 mg / kg or Asp-AMS-(OMe) at 5 mg / kg (5-on / 2-off) compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one- way ANOVA test. Figure 29 shows the volume of MCF-7 breast tumours on female NXG mice, following daily treatment with tamoxifen at 4 mg / kg or Ile-AMS at 5 mg / kg (5- on / 2-off) compared to vehicle control. (vehicle and Tamoxifen arms duplicated; same as in Figure 28). Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 30 shows the normalised body weight of female NXG mice bearing MCF-7 breast tumours following daily treatment with Tamoxifen at 4 mg / kg, Asp-AMS- (OMe) at 5 mg / kg compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 31 shows the normalised body weight of female NXG mice bearing MCF-7 breast tumours following daily treatment with Tamoxifen at 4 mg / kg, Ile-AMS at 5 mg / kg (5-on / 2-off) compared to vehicle control. (vehicle and Tamoxifen arms duplicated; same as in Figure 30). Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. (ns=non-significant). Figure 32 shows the volume of T-47D breast tumours on female NXG mice, following daily treatment with tamoxifen at 4 mg / kg or Asp-AMS-(OMe) at 5 mg / kg (5-on / 2-off) compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one- way ANOVA test. Figure 33 shows the volume of T-47D breast tumours on female NXG mice, following daily treatment with tamoxifen at 4 mg / kg or Ile-AMS at 5 mg / kg (5- on / 2-off) compared to vehicle control. (vehicle and Tamoxifen arms duplicated; same as in Figure 32). Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 34 shows the digital biomarker (defined here as tumour proliferation index (Ki67 expressing proliferative cells) divided by tumour apoptotic index (quantifying apoptotic cells with CC-3 expression) in excised T-47D breast tumour (n=3 in each condition) following treatment with Asp-AMS(OMe) or Ile-AMS. Tamoxifen was used as a control (A, B). (vehicle and Tamoxifen arms duplicated in A & B). Statistical significance was calculated using a one-way ANOVA test. Figure 35 shows the normalised body weight of female NXG mice bearing T-47D breast tumours following daily treatment with Tamoxifen at 4 mg / kg, Asp-AMS- (OMe) at 5 mg / kg compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 36 shows the normalised bodyweight of female NXG mice bearing T-47D breast tumours following daily treatment with Tamoxifen at 4 mg / kg, Ile-AMS at 5 mg / kg (5-on / 2-off) compared to vehicle control. (vehicle and Tamoxifen arms duplicated; same as in Figure 35). Values shown are mean ±SEM; initially n=8 for all treatment groups. Statistical significance was calculated using a one-way ANOVA test. Figure 37 shows the volume of BxPC-3 pancreatic tumour xenograft established in female Balb / c nude mice, following treatment with Gemcitabine (60 mg / kg, intraperitoneal injection once a week) or oral Asp-AMS-(OMe) at 5 mg / kg (5-day on / 2-day off for the first two weeks, then escalated to daily dosing) compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. An unpaired t-test with Welch’s correction was used to determine statistical significance. Figure 38 shows the percentage of cells expressing apoptotic marker (CC-3) (Fig. 38A) and proliferation markers (Ki67) (Fig.38B) in BxPC-3 tumour xenografts following treatment with Asp-AMS(OMe) or Gemcitabine. CC-3 levels were quantified in tumours to determine tumour apoptotic index following oral administration of Asp-AMS(OMe) or intraperitoneal administration of Gemcitabine to tumour-bearing mice (A, B). Statistical significance was calculated using one-way ANOVA test. (ns=non-specific) Figure 39 shows the normalised bodyweight of female Balb / c nude mice bearing BxPC-3 pancreatic tumours following oral administration of Asp-AMS(OMe) or intraperitoneal administration of Gemcitabine compared to vehicle control. Values shown are mean ±SEM; initially n=8 for all treatment groups. Examples set out to identify functionally relevant androgen receptor-associated AFs) that are important in driving AR transcriptional activity during prostate cancer (PCa) development and progression to castration-resistant prostate cancer (CRPC). In doing so, the inventors identified an unexpected interaction between the androgen receptor and aminoacyl-tRNA synthetases (AARSs). From this discovery, the inventors set out to determine whether the inhibition of AARSs, such as DARS, by catalytic inhibition or siRNA depletion, could inhibit and prevent the growth of prostate cancer. Materials and Methods Cell lines culture conditions and authentication Prostate cancer cell lines (LNCaP, C4-2B, 22Rv1, DU145, R1-AD1 and R1-D567) and benign prostate epithelial cells (RWPE-1) were obtained from commercial suppliers and authenticated by short tandem repeat (STR) genotyping. Cells were cultured and maintained in an incubator at 37°C with an atmosphere of 5% CO2 as recommended by a commercial supplier. For androgen stimulation, cells were plated in media supplemented with 5% of charcoal-stripped serum (CSS) for 24 hours prior to being stimulated with 1 nM R1881 (Metribolone, (17b)-17-Hydroxy- 17-methyl-Estra-4,9,11-trien-3-one) (Sigma). Cell treatments with Enzalutamide (Selleckchem) final concentrations of 1 or 10 μM were used, and for Asp-AMS (5'- O-[N-(L-Aspartyl) sulfamoyl] adenosine) (MedChemExpress), the final concentrations used ranged from 0.5 to 10 μM. Asp-AMS(OME) and Iso-AMS were synthesised by O2H Discovery. Analysis of cell growth Cell growth after treatment with Asp-AMS was assessed using the Incucyte® SX5 Live-Cell Analysis System (Sartorius). Cells were seeded in 96-well plates at the required seeding density and treated 24 hours after with treatment conditions in triplicates. Growth was monitored for at least 120 hours via phase-contrast images taken every 3 hours. Confluence was assessed by default settings of the Incucyte® SX5 software in relation to the starting point zero hours. Cell viability MTS assay Cell viability was assessed using the CellTiter 96® AQueous MTS Reagent Powder, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H- tetrazolium; inner salt (Promega), which measures the metabolic activity of cells indicating the number of living cells in culture. Cell death (Cell cycle) analysis by Annexin V and 7-AAD staining Cells were counted and plated at the required seeding density under the desired treatment conditions. After completion of treatment, cells were harvested and were resuspended in 1X Annexin V Binding Buffer supplemented with PE Annexin V and 7-AAD, as recommended by the manufacturer (BD Biosciences). Samples were incubated in the dark and resuspended with an additional 1X Annexin V Binding Buffer. Flow cytometry analysis for viable, apoptotic, and necrotic cells were performed using the MACSQuant® Analyzer 10. siRNA-mediated gene knockdown DARS (J-010334-06), IARS (J-009272-12), AR (J-003400-07) and siSCR (non- targeting control) (D-001810-01) siRNA transient transfections of cells were done using the reverse transfection method using a final siRNA concentration of 10 nM. Reverse transfections were performed using Lipofectamine RNAiMAX (Invitrogen) following instructions from supplier Dharmacon (Horizon Discovery). After transfection, cells were incubated at 37°C in 5% CO2 for the appropriate time. Viability of the cells was assessed at five days post-transfection and RT-qPCR and Western blot analysis were performed at 72 hours post-transfection. Whole-cell and cell fractionation lysate preparation and western blot analysis Cell lysates were prepared in 1x RIPA lysis buffer (Millipore) which contained proteases (Roche) and phosphatases (Roche) inhibitor cocktail mix diluted 1:100. To obtain cytoplasmic and nuclear fractions, a buffer containing 10 mM Hepes pH 7.9, 10 mM KCl, 1.5 mM MgCl2, 0.34 M sucrose, and 10% glycerol supplemented with 0.1 % of Triton X-100, was used. Nuclear fractions were obtained using buffer containing 3mM EDTA, 0.2 mM EGTA. Nuclear fraction DNA was disrupted by 3-5 cycles of 30 seconds ON / OFF sonication ultrasonic disintegrator Soniprep 150 (MSE) with the Exponential Microprobe (3 mm diameter tip) and an amplitude of 7.5 microns. Protein quantification of whole and fractionated cell lysates was done using the Pierce™ BCA Protein Assay Kit, (Life technologies) by following the manufacturer’s protocol. Samples were stored at -80°C. Co-Immunoprecipitation Co-IPs experiments for AR, IARS and DARS were performed using Protein A Dynabeads® (Invitrogen). Antibodies used were AR (5153, Cell Signalling), IARS (ab150557, Abcam) and DARS (ab206695, Abcam). Cross-linking of beads and antibody was performed using 20 mM Dimethyl pimelimidate (DMP) (Sigma) in 0.2 M of triethanolamine (Sigma). Cross-linked beads and whole-cell lysates or cytoplasmic and nuclear fractions were incubated on a roller from 2-3 hours to overnight at 4°C. After washes with IP wash buffer containing 2% of detergent, beads were resuspended in 1x NuPAGE® LDS loading buffer (Life Technologies) and 1x NuPAGE® sample reducing agent (Life Technologies) prepared in RIPA buffer. Beads were then incubated for 10 minutes at 70 °C and samples were run straight away on an SDS-PAGE gel or stored at -20°C. SDS-PAGE and Western Blot analysis Samples were prepared with 1x NuPAGE® LDS loading buffer (Life Technologies) and 1x NuPAGE® sample reducing agent (Life Technologies) and boiled in a heating block for 10 minutes at 70°C. Samples were then loaded on NuPAGE 4-12% bis-Tris gels (Invitrogen) and the gel tank was filled with 1X MOPS-SDS (3-(N-morpholino) propane sulfonic acid-sodium dodecyl sulphate) running buffer (Invitrogen). Gels were run under a voltage of 120 V for varying durations depending on the target protein size. A PageRuler™ Plus Prestained Protein Ladder (Thermo Fisher) was used as a molecular weight marker. Proteins were then transferred to a nitrocellulose membrane by using the iBlot® 2 Dry Transfer System (Invitrogen), and the membrane was blocked with 5% non-fat dry milk powder in tris-buffered 5 saline containing 0.1% Tween 20 (TBS-T) for 1 h at room temperature, and incubated overnight at 4 °C with the following primary antibodies: AR ( sc-816, SCT), IARS (ab150557, Abcam), DARS (ab181985, Abcam), β-Actin (8457, CST). Membranes were then incubated with anti-rabbit or anti-mouse antibodies for one hour at room temperature, washed and incubated with SuperSignal® West Femto 10 chemiluminescent substrate (Life Technologies). Images were taken using the ChemiDoc-It2 imager in combination with VisionWorkLS Software (Ultra-violet products Ltd, UVP). Real-time quantitative PCR 15 To identify relative target gene expression, total RNA was extracted from cell lines using the RNeasy® Plus Micro / Mini Kit (Qiagen), according to the manufacturer’s instructions. RNA was converted into cDNA using the QuantiNovaTM Reverse Transcription Kit (Qiagen) by following the manufacturer’s instructions. Quantitative PCR (qPCR) was performed using 10 ng of cDNA per reaction using the Stratagene 20 Mx3000P qPCR System (Agilent Technologies). QuantiNovaTM SYBR® Green PCR Kit (Qiagen) was used to measure the amount of PCR product. Primer sequences are provided in Table 1. Table 1: Primer sequences for RT-qPCR 25 Target Forward primer SEQ SEQ ID Reverse primer ID Application No No AR GGACATGCGTTTGGAGACTG4CAATCATTTCTGCTGGCGCA5RT-qPCR KLK3 TGTGCTTCAAGGTATCACGTCAT6TTGATCCACTTCCGGTAATGC7RT-qPCR TMPRSS2 CCATTTGCAGGATCCGTCTG8GGATGTGTCTTGGGGAGCAA9RT-qPCR NKX3.1 AGAAGGCCTCCTCTTTCAGG10GCCAAGAACCTCAAGCTCAC11RT-qPCR DARS CGCGGCGGAAGATTATGCTAAA12TGCACGTACCCAAACAACTTCA13RT-qPCR β-Actin ATGTACCCTGGCATTGCCG14GACTCGTCATACTCCTGCTTG15RT-qPCR GAPDH GACAGTCAGCCGCATCTTCT16GCGCCCAATACGACCAAATC17RT-qPCR IARS GCCCCTCAGCAACAAAATGCT18CCAGTTGCAAAAGGAGGACCA19RT-qPCR Rapid Immunoprecipitation Mass Spectrometry of Endogenous Proteins (RIME) The RIME experiment was performed at the Cancer Research UK Cambridge 5 Institute, University of Cambridge) Proteomics facility through a fee-for-service contract. Cells (10 x 106) were grown in a 15 cm plate with complete media. After a relevant time, the media was removed and replaced with a 2 mM solution of disuccinimidyl glutarate (DSG) (Santa Cruz Biotechnologies) in PBS for 20 minutes of cross-linking. The DSG solution was discarded and replaced with 1% 10 formaldehyde (Polysciences) for a second cross-linking of 10 minutes. Crosslinking was quenched with Glycine 1.25 M to a final concentration of 0.125 M and cells were washed with PBS and harvested in 1.5 ml tubes. The nuclear fraction of the cells was extracted by resuspending the pellets in 1 ml of Lysis Buffer 1 (50 mM HEPES-KOH (pH 7.5), 140 mM NaCl, 1 mM EDTA, 10% glycerol, 0.5% NP-40 and 15 0.25% Triton X-100) and mixed for 10 minutes at 4°C. Cells were pelleted and resuspended in 1 ml of Lysis Buffer 2 (10 mM Tris-HCL (pH 8.0), 200 mM NaCl, 1 mM EDTA and 0.5 mM EGTA) and mixed for 5 minutes at 4°C. Cells were pelleted again and resuspended in 300 μl of Lysis Buffer 3 (10 mM Tris-HCl (pH 8), 100 mM NaCl, 1 mM EDTA, 0.5 mM EGTA, 0.1% Na-deoxycholate and 0.5% N- 20 lauroylsarcosine). Samples were then sonicated using the ultrasonic disintegrator Soniprep 150 (MSE) for 10 cycles with intermittent 30 seconds ON and 30 seconds OFF, to obtain approximately 200-600 bp chromatin fragment sizes. Samples were then incubated with magnetic Dynabeads™ Protein A (Invitrogen) previously bounded with 20 μg of antibody AR (ab7472, Abcam), and immunoprecipitated 25 overnight at 4°C. The next day, beads were washed 10 times with 1 ml of RIPA buffer and twice with 100 mM of ammonium hydrogen carbonate solution (AMBIC) (Sigma) and stored at -80°C. Tryptic digestion, peptide desalting and mass spectrometry, were performed by 30 Proteomics Core Facility in the CRUK-Cambridge Institute. Briefly, tryptic digestion was performed by adding 10 μl of trypsin (10 μg / ml in 100 mM AMBIC) directly onto the beads and incubating overnight at 37°C. After, the tubes were placed on a magnetic rack to collect supernatant which was directly placed into formic acid to give a final concentration of 5%. Peptide mixtures were desalted using C18 ultra 35 micro spin columns and eluted with 50 μl of 60% (v / v) acetonitrile / 0.1% (v / v) formic acid. The eluted peptides were then completely dry by vacuum centrifugation. Each sample was reconstituted in 10 μl of loading buffer (0.1% formic acid / 2% acetonitrile / water) and 2-5 μl aliquots were analysed using nano- LC-MS / MS. A flow rate of 300 nl / min was used, spraying the peptides directly into an LTQ Velos-Orbitrap MS (Thermo Scientific) using collision-induced for peptide ion fragmentation. For quantitative RIME (qPLEX-RIME), digested and cleaned peptide samples were dried with speedvac, reconstituted in 100 μl of 0.1 M TEAB (triethylammonium bicarbonate), and labelled using TMT 10plex reagents (Thermo Fisher) with a randomised design. The peptide mixture was then fractionated with Reversed-Phase cartridges at high pH (Pierce). Nine fractions were collected using different elution solutions in the range of 5–50% ACN. Peptide fractions were then analysed on a Dionex Ultimate 3000 UHPLC system coupled with the nano-ESI Fusion Lumos (Thermo Scientific). Data processing was carried out by Proteomics Core Facility from the CRUK- Cambridge Institute. Quantitative RIME (qPLEX-RIME) raw MS data files were processed using Proteome Discoverer 2.1 software (Thermo Scientific) and SequestHT as a search engine against UniProt human database for peptide and protein identifications. The node for SequestHT included the following parameters: Precursor Mass Tolerance 20 ppm, Fragment Mass Tolerance 0.5 Da, Dynamic Modifications were Oxidation of M (+15.995 Da), Deamidation of N, Q (+0.984 Da) and Static Modifications were TMT6plex at any N-Terminus, K (+229.163 Da) for the quantitative data. Methylthio at C (+45.988) was included for the total proteome data. The Reporter Ion Quantifier node included a TMT 6plex (Thermo Scientific Instruments) quantification method. Quantitative datasets were imported into R and were analysed using the qPLEXanalyzer tool using a limma-based differential analysis to identify differential abundant proteins. Unique peptides identified with high confidence (peptide FDR < 1%) were used for the analysis. A multiple testing correction was applied on the p-value using the Benjamini- Hochberg method to control the FDR. 22Rv1 prostate tumour xenografts Male Balb / c mice aged 5-9 weeks, weighing approximately 23-30g were used for the study. Animals were housed in IVC cages (up to 5 per cage) with individual mice identified by tail mark. All animals were allowed free access to a standard certified commercial diet and sanitised water during the study. The animal holding room was maintained as follows - room temperature at 20-24°C, humidity at 45- 65% and a 12h light / dark cycle used. All pre-clinical protocols / procedures were carried out under the guidelines of the Animal (Scientific Procedures) Act 1986. Tumour cell implantation, maintenance & observations Castration resistant 22Rv1 prostate cancer cells (5x106in 1:1 Matrigel) were implanted subcutaneously onto the flank of male Balb / c nude mice using a 23- gauge needle. Once tumours reached approximately 150 mm3, mice with similar- sized tumours were assigned to treatment groups. Eight animals were enrolled into each treatment group on staggered basis due to tumours growing at the different rates. Bodyweight was measured three times weekly. Tumour volume was also measured three times weekly. Drug Formulation: Enzalutamide was formulated daily in 5% DMSO: 95% methylcellulose (0.5% w / v in UP water): 0.1% Tween-80. A 1 mg / ml solution was prepared for the 10 mg / kg daily oral dosing. The dosing solution was administered orally at 10 ml / kg daily for 28 days. ASP-AMS-(OMe) was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. A 0.5 mg / ml solution was prepared for the 10 mg / kg daily dose. The dosing solution was administered orally at 10 ml / kg daily for 28 days. Ile-AMS was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. A 0.5 mg / ml solution was prepared for the 5 mg / kg daily dose. The dosing solution was administered orally at 10 ml / kg daily for 28 days. Terminal Sampling: Following study completion, tumours were resected, formalin-fixed and tumours from between 4 to 6 mice from each treatment group were sectioned and stained for Ki-67 (a marker for proliferation) and CC-3 (a marker for cell death via apoptosis) using immune-histochemistry. Statistical analysis The statistical significance was analysed using one-way ANOVA employing Dunnett’s multiple comparison test. C4-2B prostate tumour xenografts Male Balb / c mice aged 5-9 weeks, weighing approximately 23-30g were used for the study. Animals were housed in IVC cages (up to 5 per cage) with individual mice identified by tail mark. All animals were allowed free access to a standard certified commercial diet and sanitised water during the study. The animal holding room was maintained as follows - room temperature at 20-24°C, humidity at 45- 65% and a 12h light / dark cycle was used. All pre-clinical protocols / procedures were carried out under the guidelines of the Animal (Scientific Procedures) Act 1986. Tumour cell implantation / Maintenance & observations: Prostate cancer C4-2B cells (5x106in 1:1 Matrigel) were implanted subcutaneously onto the flank of male Balb / c nude mice using a 23-gauge needle. Once tumours reached approximately 150 mm3, mice with similar-sized tumours were assigned to treatment groups. Eight animals were enrolled into each treatment group on a staggered basis due to tumours growing at the different rates. Bodyweight was measured three times weekly. Tumour volume was also measured three times weekly. Drug Formulation: Enzalutamide was formulated daily in 5% DMSO: 95% methylcellulose (0.5% w / v in UP water): 0.1% Tween-80. A 1 mg / ml solution was prepared for the 10 mg / kg dose. The dosing solution was administered orally at 10 ml / kg daily for 29 days. ASP-AMS-(OMe) was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. A 0.5 mg / ml solution was prepared for the 10 mg / kg dose. The dosing solution administered orally at 10 ml / kg daily for 29 days. Ile-AMS was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. A 0.5 mg / ml solution was prepared for the 5 mg / kg dose. The dosing solution was administered orally at 10 ml / kg daily for 29 days. Terminal Sampling: Following study completion, tumours were resected, formalin fixed and tumours from between 4 to 6 mice from each treatment group were sectioned and stained for Ki-67 and CC3 using immune-histochemistry. Blood sampled on days 0, 14, 21, and 28 (terminal) and plasma were prepared. PSA ELISA was run to evaluate the PSA levels in mouse blood. Statistical analysis: The statistical significance was analysed using one-way ANOVA employing Dunnett’s multiple comparison test. MCF-7 breast tumour xenografts Female NXG mice aged 5-9 weeks, weighing approximately 17-24g were used for the study (Janvier Laboratories). Animals were housed in IVC cages (up to 5 per cage) with individual mice identified by tail mark. All animals were allowed free access to a standard certified commercial diet and sanitised water during the study. The animal holding room was maintained as follows - room temperature at 20- 24°C, humidity at 45-65% and a 12h light / dark cycle was used. All pre-clinical protocols / procedures were carried out under the guidelines of the Animal (Scientific Procedures) Act 1986. Tumour cell implantation / Maintenance & observations: At least 7 days prior to tumour cell implantation animals were given unlimited access to oestrogen-supplemented drinking water (8µg / ml). Tumour cells were implanted in Female NXG mice with MCF-7 cells (5 x 106in 1:1 Matrigel) into the second inguinal mammary fat pad under anaesthesia (inhaled). When tumours reached approximately 100mm3animals were assigned to the treatment groups to ensure an equal spread of tumour volume. Bodyweight was measured three times weekly. Tumour volume was also measured three times weekly using digital callipers. Drug Formulation: Tamoxifen was formulated daily for dosing in 0.3% hydroxypropyl cellulose. The concentration of the dosing solution administered was 0.8 mg / ml for subcutaneous administration at 5 ml / kg, daily at 4 mg / kg for 27 days. ASP-AMS-(OMe) was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. A 0.5 mg / ml solution was prepared for the 10 mg / kg dose. The dosing solution was administered orally at 10 ml / kg (5-on / 2-off) for 27 days. Ile-AMS was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. A 0.5 mg / ml solution was prepared for the 5 mg / kg dose. The dosing solution was administered orally at 10 ml / kg (5-on / 2-off) for 27 days. Terminal Sampling: Following study completion, tumours were resected, formalin fixed and tumours from between 4 to 6 mice from each treatment group were sectioned and stained for Ki-67 and CC-3 using immune-histochemistry. Statistical analysis: The statistical significance was analysed using one-way ANOVA employing Dunnett’s multiple comparison test. T-47D breast tumour xenografts Female NXG mice aged 5-9 weeks, weighing approximately 17-24g were used for the study (Janvier Laboratories). Animals were housed in IVC cages (up to 5 per cage) with individual mice identified by tail mark. All animals were allowed free access to a standard certified commercial diet and sanitised water during the study. The animal holding room was maintained as follows - room temperature at 20- 24°C, humidity at 45-65% and a 12h light / dark cycle was used. All pre-clinical protocols / procedures were carried out under the guidelines of the Animal (Scientific Procedures) Act 1986. Tumour cell implantation / Maintenance & observations: At least 7 days prior to tumour cell implantation animals were given unlimited access to oestrogen-supplemented drinking water (8µg / ml). Tumour cells were implanted in Female NXG mice with T-47D cells (5 x 106in 1:1 Matrigel) into the second inguinal mammary fat pad under anaesthesia (inhaled). When tumours reached approximately 100mm3animals were assigned to the treatment groups to ensure an equal spread of tumour volume. Bodyweight was measured three times weekly. Tumour volume was also measured three times weekly using digital callipers. Drug Formulation: Tamoxifen was formulated daily for dosing in 0.3% hydroxypropyl cellulose. The concentration of the dosing solution administered was 0.8 mg / ml for subcutaneous administration at 5 ml / kg, daily at 4 mg / kg for 27 days. ASP-AMS-(OMe) was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. A 0.5 mg / ml solution was prepared for the 10 mg / kg dose. The dosing solution was administered orally at 10 ml / kg (5-on / 2-off) for 27 days. Ile-AMS was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. A 0.5 mg / ml solution was prepared for the 5 mg / kg dose. The dosing solution was administered orally at 10 ml / kg (5-on / 2-off) for 27 days. Terminal Sampling: Following study completion, tumours were resected, formalin-fixed and tumours from between 4 to 6 mice from each treatment group were sectioned and stained for Ki-67 and CC-3 using immune-histochemistry. Statistical analysis: The statistical significance was analysed using one-way ANOVA employing Dunnett’s multiple comparison test. BxPC-3 pancreatic tumour xenografts Female Balb / c nude mice aged 5-9 weeks, weighing approximately 16-22g were used for the study. Animals were housed in IVC cages (up to 5 per cage) with individual mice identified by tail mark. All animals were allowed free access to a standard certified commercial diet and sanitised water during the study. The animal holding room was maintained as follows - room temperature at 20-24°C, humidity at 45-65% and a 12h light / dark cycle was used. All pre-clinical protocols / procedures were carried out under the guidelines of the Animal (Scientific Procedures) Act 1986. Tumour cell implantation / Maintenance & observations: Gemcitabine-resistant BxPC-3 pancreatic cancer cells (1x107 in 1:1 Matrigel) were implanted subcutaneously onto the flank of female Balb / c nude mice using a 23- gauge needle. Once tumours reached approximately 100 mm3, mice with similar- sized tumours were assigned to treatment groups. Eight animals were enrolled into each treatment group on a staggered basis due to tumours growing at different rates. Bodyweight was measured three times weekly. Tumour volume was also measured three times weekly using digital callipers. Drug Formulation: Gemcitabine: Gemcitabine was formulated fresh on the day of each dosing occasion in 5% DMSO: 10% Solutol: 85% saline. The final dosing matrix was a clear solution at a concentration of 6 mg / mL. IP administration of this solution at 10 mL / kg was used to deliver effective doses of 60 mg / kg once weekly. ASP-AMS-(OMe): was formulated daily in 2% DMSO: 30% PEG 300: 5% Tween-80: 63% Ultra-pure water. The final dosing matrix will be a clear solution at a concentration of 0.5 mg / mL. PO administration of this solution at 10 mL / kg was used to deliver effective doses of 5 mg / kg. To the BxPC-3 model, mice were first administered Asp-AMS(OMe) on a 5-day on / 2-day-off basis for the first two weeks and then daily for the last 2 weeks. Vehicle animals were dosed with: 2% DMSO: 30% PEG300: 5% Tween-80: 63% Ultra-Pure water. Terminal Sampling: Following study completion, tumours were resected, formalin-fixed and tumours from between 3 to 6 mice from each treatment group were sectioned and stained for Ki-67 (a marker for proliferation) and CC-3 (a marker for cell death via apoptosis) using immune-histochemistry. Results Example 1 – AARSs are part of the AR regulatory complex To identify functionally relevant AR-associated factors (AR-Afs) that are important in driving AR transcriptional activity during PCa development and progression to CRPC, a quantitative AR qPLEX-RIME in C4-2B PCa cell lines under androgenic and Enzalutamide conditions was performed. Using this qPLEX-RIME, a targeted proteomics quantitative method, the inventors unexpectedly identified an interaction between aminoacyl-tRNA synthetases (AARSs) machinery and the androgen signalling (Figure 1). This suggests a novel non-canonical function of AARSs. Example 2 – DARS interacts with AR and modulates its transcriptional activity The inventors next set out to identify whether an AR and Aspartyl tRNA-synthetase (DARS), as one synthetases (AARSs). Physical interaction between AR and DARS was surprisingly confirmed by forward and reverse co-IP experiments in PCa cell lines expressing different AR isoforms (Figure 2). This suggests that DARS interacts not only with full-length androgen receptor (AR-FL) but also with AR variants (AR-Vs). Additionally, the inventors demonstrated that DARS siRNA-mediated knockdown significantly reduces the cell viability of four of the five genetically different cell lines included in a cell panel containing one immortalised prostate epithelial cell line (RWPE-1) and four PCa cell lines (C4-2B, 22Rv1, R1-AD1, and R1-D567) (Figure 3). Furthermore, DARS modulation of AR transcriptional activity was assessed by evaluating the gene expression of three well-known AR target genes (ARTGs), KLK3, TMPRSS2, and NKX3.1, after DARS silencing. As shown in Figure 4, DARS siRNA-mediated knockdown reduces AR transcriptional activity in PCa cell lines LNCaP, C4-2B, and 22Rv1, as demonstrated by the reduced gene expression of the ARTGs. Example 3 – DARS expression is regulated by the AR signalling axis The inventors demonstrated that DARS expression is significantly reduced after AR depletion in PCa cell lines, LNCaP, C4-2B and 22Rv1 (Figure 5A, 5B and 5C), and its expression is increased by androgens in androgen-sensitive PCa cell lines, LNCaP and C4-2B (Figure 5D and 5E). DARS depletion induced a slight increase of AR gene expression in LNCaP cells (Figure 5A), while C4-2B cells exhibited a slight decrease in AR gene expression (Figure 5B). In the 22Rv1 cell line the depletion of DARS decreased expression of not only AR-FL but also AR-V7 to a similar extent (Figure 5C). Example 4 – Inhibition of the catalytic function of DARS by an analogue of Aspartyl- an analogue of called Asp- as a strategy in PCa. Asp-AMS (Cas No: 828288-98-8) is an Aspartyl-tRNA synthetase inhibitor. LNCaP and C4-2B cells, both androgen-responsive, showed different responses to Asp-AMS treatment. LNCaP cells showed a decrease in cell growth comparable to the decrease induced by 10 μM dose of the currently available standard-of-care drug, Enzalutamide, when treated with 4 μM dose of Asp-AMS (Figure 6A). C4-2B cells showed a decrease in cell growth comparable to the one induced by 10 μM dose of Enzalutamide when treated with concentrations equal or higher than 2.5 μM dose of Asp-AMS (Figure 6B). The 22Rv1 cell line, which has a more aggressive phenotype than LNCaP and C4-2B cell lines and is Enzalutamide-resistant, exhibited a strong decrease in cell growth induced by Asp-AMS. Although initially, cell growth was enhanced at the lowest concentration of 0.5 μM Asp-AMS, potentially due to a non-specific stress response of the cells, these exhibited a strong inhibition of cell growth from 1.5 μM of Asp-AMS (Figure 6C). Accordingly, this demonstrates that the treatment of cellular models of PCa with Asp-AMS is more efficient in comparison to the standard of care, Enzalutamide. Additionally, the inventors demonstrated that inhibition of the catalytic function of DARS by Asp-AMS inhibits the growth of PCa cell lines by triggering apoptosis (Figure 7). LNCaP cells reduced the number of apoptotic cells induced by 10 μM Asp-AMS by 26% when co-treated with androgens (Figure 7A). C4-2B cells reduced the number of apoptotic cells induced by 10 μM Asp-AMS by 11% when co-treated with androgens (Figure 7B).22Rv1 cells did not show any reduction in the number of apoptotic cells when co-treated with androgens (Figure 7C). Therefore, sensitivity to Asp-AMS seems to be linked to the androgen responsiveness of the PCa cells, being able to reduce sensitivity to Asp-AMS in androgen-responsive cell lines compared to androgen-independent cell lines. Example 5 – DARS inhibition directly affects AR protein levels and subcellular localisation The inventors have further demonstrated that Asp-AMS decreases AR protein levels in androgen-independent cell lines. Asp-AMS has different effects on AR and DARS protein levels between cell lines. LNCaP cells treated with 2.5 μM Asp-AMS showed no effect on AR and DARS protein levels or subcellular localisation (Figure 8A). C4- 2B cells treated with 2.5 μM Asp-AMS showed no effect on AR and DARS protein levels but a slight decrease in AR nuclear levels was observed after treatment (Figure 8B). Castrate resistant, androgen-independent 22Rv1 cells, which were shown to be more sensitive to Asp-AMS, exhibited a robust decrease of AR and AR- V protein levels, as well as DARS protein levels reflected on cytoplasmic and nuclear fractions (Figure 8C). Furthermore, the inventors demonstrated that Asp-AMS decreases AR transcriptional activity in androgen-independent cell lines. AR and AR-V7 transcripts were significantly reduced in 22Rv1 cells by Asp-AMS, which was shown to be highly sensitive to Asp-AMS treatment (Figure 9C). Example 6 – IARS interacts with AR and modulates its transcriptional activity The inventors next set out to demonstrate that an interaction occurs between AR and Isoleucyl tRNA-synthetase (IARS), as another example of the aminoacyl-tRNA synthetases (AARSs). As illustrated in Figure 10, the androgen receptor (AR) competes with Isoleucyl tRNA to physically interact with IARS, i.e. AR and IARS mutually interact with each other. This interaction is enhanced following treatment with RNase A indicating competition between AR and Isoleucyl tRNA to bind to IARS. Additionally, the inventors demonstrated that IARS depletion reduces AR and AR-V7 transcript expression. As shown in Figure 11, AR full-length expression was significantly reduced following the silencing of IARS in both C4-2B and 22Rv1 prostate cancer (PCa) cell lines. AR-V7 expression was also significantly reduced following siRNA-mediated IARS silencing in 22Rv1 cells. Furthermore, the inventors also demonstrated that siRNA-mediated IARS depletion reduces AR protein levels. C4-2B and 22Rv1 PCa cell lines were fractionated following IARS silencing in order to examine more specifically where in the cell AR depletion was occurring. Western blot analysis indicated that IARS silencing reduced AR protein levels more specifically in nuclear fractions (Figure 12). Additionally, IARS modulation of AR transcriptional activity was assessed by evaluating the gene expression of three well-known AR target genes (ARTGs), KLK3, TMPRSS2 and NKX3.1, following IARS silencing in C4-2B and 22Rv1 cell lines. As illustrated in Figure 13, IARS silencing alters the gene expression of AR target genes. Example 7 – Inhibition of the catalytic function of IARS by an analogue of Isoleucyl - cells with the Iso- referred to as , and ARTG (KLK3 and NKX3.1) was analysed. A significant reduction in gene expression was observed when treated with Iso-AMS (Figure 14). This demonstrates that the IARS inhibitor Iso-AMS represses AR and AR target gene transcription. Furthermore, the effect of IARS inhibitor Iso-AMS on the growth of PCa cell lines was analysed. Treatment of LNCaP, C4-2B and 22Rv1 cell lines with Iso-AMS reduced androgen R1881-induced cell viability. The inhibition of growth was more pronounced than Enzalutamide (Figure 15B,D,F). Similar to IARS depletion, the inventors also demonstrated that Iso-AMS alters the protein expression of the AR. Following the treatment of C4-2B cells with Iso-AMS, a reduction in the protein expression of both the AR and IARS was observed in the whole cell lysate (Figure 16). Finally, the inventors demonstrated that orally administered Iso-AMS is safe in vivo. Following the administration of 10 mgs / kg Iso-AMS, the weight on animals was measured on a daily basis for 14 days. No decrease was observed in mice weight at the end of the experiment (Figure 17). Example 8 - Preclinical efficacy of Aspartyl tRNA Synthetase inhibitor Asp- AMS(OMe) and Isoleucyl tRNA in (A) inhibitor Asp-AMS(OMe) and Isoleucyl tRNA Synthetase inhibitor Ile-AMS in repressing 22Rv1 tumour xenografts As expected, treatment with Enzalutamide at 10 mg / kg (daily; QD) had no significant effect on the growth of 22Rv1 tumours, compared to vehicle-treated controls (p=0.1028) (Figure 18 & duplicated in Figure 19 to allow comparison with Ile-AMS group). Treatment with Asp-AMS(OMe) at 5 mg / kg QD significantly controlled the growth of castrate-resistant 22Rv1 tumours compared to vehicle control and a(p=0.0057) and Enzalutamide. Treatment with Ile-AMS at 5 mg / kg QD also significantly controlled the growth of castrate-resistant 22Rv1 tumours compared to vehicle control(p=0.0002) and Enzalutamide (Figure 19). B) Effect of Aspartyl tRNA Synthetase inhibitor Asp-AMS(OMe) and Isoleucyl tRNA Synthetase inhibitor Ile-AMS on proliferative and apoptotic markers in C4-2B tumour xenografts Immunohistochemistry analysis to detect proliferation marker Ki67 and apoptotic marker cleaved caspase-3 (CC3) was performed. While Enzalutamide did not increase apoptotic index, both Asp-AMS(OMe) (p=0.015) and Ile-AMS increased (p=0.0079) CC-3 levels indicating promotion of apoptosis / cell death by both drugs where the standard of care drug Enzalutamide fails to induce apoptosis (Figures 20A & B). The tumour proliferative index (measured by nuclear H-Score of Ki67 positive tumour cells) remained unaffected by Enzalutamide, marginally decreased Asp-AMS(OMe) (p=0.07), but Ile-AMS treated tumours showed a significant decrease in proliferation (p=0.38). (C) Effect of drugs on body weight of mice bearing 22Rv1 tumour xenografts Treatment with Enzalutamide at 10 mg / kg was well tolerated in 22Rv1 tumour- bearing Balb / c nude mice throughout the study period (Figures 21 and 22, same observation duplicated). No evidence of bodyweight loss or any other effects on animal appearance or behaviour was recorded. This agent had no effect on the growth of 22Rv1 tumours. Asp-AMS-(OMe) at 5 mg / kg was tolerated, although all animals receiving this treatment displayed a marginal bodyweight loss at some point during the treatment period (p=0.0003) (Figure 21). All animals made it to the end of the treatment period with no evidence of any other effects on animal appearance or behaviour recorded. Treatment with Ile-AMS at 5 mg / kg was also well tolerated, all animals receiving this treatment displayed marginal, statistically insignificant bodyweight loss at some point during the treatment period (Figure 22). Example 9 - Preclinical efficacy of Aspartyl tRNA Synthetase inhibitor Asp- AMS(OMe) and Isoleucyl tRNA in C4- (A) tRNA Synthetase inhibitor Asp-AMS(OMe) and Isoleucyl tRNA Synthetase inhibitor Ile-AMS in repressing C4-2B tumour xenografts Treatment with Enzalutamide at 10 mg / kg was well tolerated in C4-2B tumour- bearing Balb / c nude mice throughout the study period. This standard-of-care drug had a significant effect on the growth of C4-2B tumours (p=0.0007). (Figure 23 & duplicated in Figure 24 to allow comparison with Ile-AMS group). Compared to Enzalutamide, half the Daily dose of Asp-AMS(OMe) at 5 mg / kg resulted in significant control of the C4-2B tumour model (p=0.0002) (Figure 23). Treatment with Ile-AMS at 5 mg / kg QD (daily) significantly controlled the growth of C4-2B tumours compared to vehicle controls (p<0.0001) (Figure 24). (B) Effect of Aspartyl tRNA Synthetase inhibitor Asp-AMS(OMe) and Isoleucyl tRNA Synthetase inhibitor Ile-AMS on proliferative and apoptotic markers in C4-2B tumour xenografts Immunohistochemistry to detect proliferation marker Ki67 and apoptotic marker cleaved caspase-3 (CC3) was performed. While Enzalutamide did not increase the apoptotic index, both Asp-AMS(OMe) and Ile-AMS increased it (Figures 25A & B). The proliferative index was decreased by Enzalutamide, and both by Asp-AMS(OMe) and Ile-AMS. (C) Effect on tumour-bearing mouse body weight of Aspartyl tRNA Synthetase inhibitor Asp-AMS(OMe) and Isoleucyl tRNA Synthetase inhibitor Ile-AMS treatment Treatment with Enzalutamide at 10 mg / kg was well tolerated in C4-2B tumour- bearing Balb / c nude mice throughout the study period (Figure 26 and duplicated in Figure 27 to allow comparison with Ile-AMS group). No evidence of bodyweight loss or any other effects on animal appearance or behaviour was recorded. Asp-AMS-(OMe) at 5 mg / kg was tolerated, although all animals receiving this treatment displayed a marginal bodyweight loss at some point during the treatment period (p<0.0001) (Figure 26). All animals made it to the end of the treatment period with no evidence of any other effects on animal appearance or behaviour recorded. Treatment with Ile-AMS at 5 mg / kg was tolerated, and all animals receiving this treatment displayed marginal bodyweight loss at some point during the treatment period (p<0.0001) (Figure 27). Example 10 – Preclinical efficacy of Aspartyl tRNA Synthetase inhibitor Asp- AMS(OMe) and Isoleucyl tRNA Synthetase in MCF-7 tumour inhibitor Asp-AMS(OMe) and Isoleucyl tRNA Synthetase inhibitor Ile-AMS in repressing MCF-7 breast tumour xenografts Treatment with tamoxifen was well tolerated in MCF-7 tumour-bearing NXG mice throughout the study period. This agent had a significant effect on the growth of MCF-7 tumours (p=0.0002). (Figure 28 & duplicated vehicle in Figure 29 to allow comparison with Ile-AMS group). Treatment with Asp-AMS(OMe) at 5 mg / kg resulted in significant growth control of the MCF-7 tumour model (p=0.0278) (Figure 28). Treatment with Ile-AMS at 5 mg / kg also led to significantly controlled growth of MCF-7 tumours compared to vehicle controls (p=0.0007) (Figure 29). (B) Effect of drugs on the body weight of tumour-bearing mouse Treatment with tamoxifen was well tolerated in MCF-7 tumour-bearing mice throughout the study period, a small but significant increase in the body weight was noted in animals who received tamoxifen (p=0.0004)) (Figure 30 and duplicated vehicle in Figure 31 to allow comparison with Ile-AMS). In Asp-AMS(OMe) treated mice, a marginal decrease was observed in body weight (P=0.0277) (Figure 30). Asp-AMS-(OMe) at 5 mg / kg was tolerated, although all animals receiving this treatment displayed a marginal bodyweight loss at some point during the treatment period (Figure 30). Treatment with Ile-AMS at 5 mg / kg was well tolerated, all animals receiving this treatment experienced negligible bodyweight loss at any point during the treatment period (Figure 31). Example 11 – Preclinical efficacy of Aspartyl tRNA Synthetase inhibitor Asp- AMS(OMe) and Isoleucyl tRNA Synthetase in T-47D tumour inhibitor Asp-AMS(OMe) and Isoleucyl tRNA Synthetase inhibitor Ile-AMS in repressing T-47D breast cancer xenografts Treatment with tamoxifen was well tolerated in T-47D tumour-bearing Balb / c nude mice throughout the study period. This agent had a significant effect on the growth of MCF-7 tumours (p=0.0012). (Figure 32 & duplicated vehicle and tamoxifen groups in Figure 33 to allow comparison with Ile-AMS). Treatment with Asp- AMS(OMe) at 5 mg / kg (5-day on / 2-day off) resulted in significant growth control of the MCF-7 tumour model (p<0.0032) (Figure 32). Treatment with Ile-AMS at 5 mg / kg (5-day on / 2-day off) also led to significantly controlled growth of T-47D breast tumours compared to vehicle controls (p<0.0038) (Figure 33). (B) Effect of Aspartyl tRNA Synthetase inhibitor Asp-AMS(OMe), Isoleucyl tRNA synthetase inhibitor, Ile-AMS and Tamoxifen on proliferative and apoptotic markers in T47-D tumour xenografts Immunohistochemistry to detect proliferation marker Ki67 and apoptotic marker cleaved caspase-3 (CC3) was performed in three tumour tissues from each treatment condition. The digital biomarker expression was calculated. In this context, the digital biomarker was defined as the ratio of tumour proliferation index (TPI) divided by tumour apoptotic index (TAI). Both tRNA synthetase inhibitors, Asp-AMS(OMe) (p=0.0038), Ile-AMS (p=0.0059) and tamoxifen increased (0.0011) the level of digital marker indicating inhibition of T47-D tumour proliferation (Figures 34A & B). The statistical significance was calculated by the one-way ANOVA test. (C) Effect of drugs on the body weight of tumour-bearing mouse Treatment with tamoxifen was well tolerated in T-47D tumour-bearing mice throughout the study period, a small increase in the body weight was noted in animals who received tamoxifen (0.0038) (Figure 35 and with the duplicated vehicle in Figure 36). In Asp-AMS(OMe) treated mice, a marginal decrease was observed in body weight (0.0002) (Figure 35). Treatment with Ile-AMS at 5 mg / kg was tolerated, and all animals receiving this treatment experienced negligible bodyweight loss at any point during the treatment period (p<0.0001) (Figure 36). Example 12 - Preclinical efficacy of Aspartyl tRNA Synthetase inhibitor Asp- AMS(OMe) in Gemcitabine- of Aspartyl tRNA in repressing BxPC-3 tumour xenografts As expected, treatment with Gemcitabine (60 mg / kg, intraperitoneal route, once per week) had no significant effect (p=0.55) on the growth of BxPC-3 tumours, compared to vehicle-treated controls (Figure 37). Treatment with Asp-AMS(OMe) for the first half of the study (i.e.2 weeks) at 5 mg / kg as 5-day on / 2-day off and then QD for the rest two-weeks of the study significantly controlled the growth of BxPC-3 pancreatic tumours compared to vehicle controls (p=0.0031). B) Effect of Aspartyl tRNA Synthetase inhibitor Asp-AMS(OMe) on proliferative and apoptotic markers in BxPC-3 pancreatic tumour xenografts Immunohistochemistry analysis to detect proliferation marker Ki67 and apoptotic marker cleaved caspase-3 (CC3) was performed. While Gemcitabine did not increase apoptotic index, Asp-AMS(OMe) increased (p=0.05) CC-3 levels indicating promotion of apoptosis / cell death where standard-of-care drug Gemcitabine fails to induce apoptosis (Figure 38A). The tumour proliferative index (measured by nuclear H-Score of Ki67 positive tumour cells) remained unaffected by all treatments (Figure 38B). (C) Effect of drugs on the body weight of mice bearing BxPC-3 tumour xenografts Treatment with Gemcitabine and Asp-AMS(OMe) was well tolerated in BxPC-3 tumour-bearing Balb / c nude mice throughout the study period (Figure 39). No evidence of bodyweight loss or any other effects on animal appearance or behaviour was recorded. Example 13 - Preclinical efficacy of Aspartyl tRNA Synthetase inhibitors Asp- AMS(OMe) and Asp-AMS(OBn) In addition to synthesising the novel compound per se, Asp-AMS(OMe), which is the methyl ester of ASP-AMS, the inventors also made and tested another novel compound, Asp-AMS(OBn), which is the benzyl ester of ASP-AMS. They then tested the efficacy of these two esters and compared their activities in vitro against Enzalutamide and Asp-AMS, using the Asp-AMS MTS assay. Cell viability MTS assays measure changes in cell viability in response to the drug treatment given. Cell viability assays were carried out in several different cells lines in order to determine the effect that treatment with the investigational drug compounds would have in different PCa cell line models and to compare between cell lines and to the control compound, Enzalutamide. A portion of those cells were also treated with a synthetic androgen (R1881) which is a mitogen for PCa cells and should oppose the effect of the drugs. Furthermore, the differences between IC50 values (amount of compound to reduce cell viability by 50%) of those treated with or without R1881 show whether cells are sensitive to androgens of insensitive. R1881-treated cells act as a more clinically relevant model as patients will always have some free circulating androgens in the blood. Therefore, IC50 values in this model will be compared between compounds and cell lines, and the results are shown in Table 2, which summarises IC50 values generated in the cell viability assays. Table 2 - IC50 values calculated by non-linear regression analysis of cell line cell viability upon treatment with compounds (µM) Enzalutamide IC50 Asp-AMS Asp-AMS(OMe) Asp- (µM) IC50 (µM) IC50 (µM) AMS(OC6H5) IC50 (µM) LNCaP 18.0 7.6 5.3 4.8 C4-2b 26.1 6.6 5.1 3.8 22Rv1 50.9 1.2 1.4 1.1 R1-X-11 10.3 1.3 1.5 1.6 R1-D567 20.9 1.9 1.5 1.6 LNCaP-95 24.6 3.3 3.6 2.0 PC3 1959.0 17.5 3.2 2.2 CV-1 47.2 12.5 12.4 12.4 As can be seen, both of the esters of Asp-AMS killed cancer cells in vitro. Discussion To identify functionally relevant AR-associated factors (AR-Afs) that are important in driving AR transcriptional activity during PCa development and progression to CRPC, a quantitative AR qPLEX-RIME in C4-2B PCa cell lines under androgenic and Enzalutamide conditions was performed (Figure 1). This identified an unexpected interaction between AR and aminoacyl-tRNA synthetases (AARSs). Further studies to understand the functional relationship between AR and Aspartyl tRNA-synthetase (DARS) / Isoleucyl tRNA-synthetase (IARS), which were selected as two exemplar species of the AARS genus, confirmed the interaction between DARS / IARS and AR, revealing a novel and therefore non-canonical function of DARS / IARS directly modulating AR transcriptional activity and confronting the skilled person’s conventional understanding of transcription and translation as separate biological processes. The fact that DARS / IARS are an androgen / AR-regulated gene, allows AR to control translation through DARS / IARS transcription which at the same time would control AR transcriptional activity. Current PCa therapeutical intervention relies on directly targeting the androgens / AR signalling axis by using ADT. The inventors have tested using an analogue of Aspartyl-adenylate called Asp-AMS, as a potential alternative therapeutical strategy in PCa specifically to treat patients that do not respond to currently available therapies. Interestingly, treatment of cellular models of PCa with Asp-AMS showed the analogue to be more efficient, in comparison to standard of care, Enzalutamide, inhibiting cell growth by triggering apoptosis in CRPC cells 22Rv1 expressing constitutively active androgen-independent AR-Vs, than androgen-responsive LNCaP and C4-2B cell lines. Investigation of the effect of Asp-AMS treatment on AR and DARS gene and protein levels as well as AR transcriptional activity brought into light the remarkable reduction of both gene and protein levels of AR and AR-Vs and consequent reduction of AR target genes (ARTGs) expression-induced with low concentrations of Asp-AMS treatment in androgen-independent 22Rv1 cell line, which explains the higher sensitivity and low survival rates of these cells to DARS inhibition in comparison to an Enzalutamide standard dose. The distinction observed in DARS / IARS inhibition sensitivity between androgen- responsive and androgen-independent cell lines, could be exploited by drugs targeting DARS / IARS, as well as the other AARSs, to treat PCa patients by combining it with anti-androgens to inhibit AR activity as well as to treat patients suffering from incurable CRPC for whom new treatments are urgently needed. Conclusions The inventors have discovered that the androgen receptor (AR) unexpectedly interacts with components of the protein synthesis machinery in the nucleus, i.e. aminoacyl-tRNA synthetases (AARSs). Aspartyl tRNA-synthetase (DARS) and Isoleucyl tRNA-synthetase (IARS), as well as other AARS, are part of the AR nuclear regulatory complex modulating AR transcriptional activity. DARS / IARS gene expression is regulated by AR, allowing AR to control translation through DARS transcription, which at the same time would control AR transcriptional activity. As such, the inventors have surprisingly identified that the various AARS, such as the DARS or IARS enzyme for example, drive AR activity in pancreatic cancer, or hormone-dependent cancers such as prostate cancer and breast cancer. As two exemplars of the AARS, the inventors have demonstrated that the catalytic inhibition of DARS (e.g. by Asp-AMS or Ile-AMS) or IARS, or the siRNA depletion of DARS, degrades AR and its highly oncogenic variant in resistant prostate cancer cells. In particular, the inventors have demonstrated that Asp-AMS and Ile-AMS trigger apoptosis in prostate cancer cells, and is superior to the current treatment Enzalutamide, in its growth repression of prostate cancer. The inventors have also demonstrated that Asp-AMS and Ile-AMS significantly control the growth of pancreatic, prostate and breast cancer tumours, and promote apoptosis in pancreatic, prostate and breast cancer cells. In conclusion, this work has uncovered a novel relationship between transcription and translation, opening up the possibility of a potential alternative therapeutic strategy in pancreatic cancer, or hormone-dependent cancers, such as prostate and breast cancer. Specifically, this could be used to treat patients who do not respond to currently available therapies, by targeting DARS and other AARSs, to treat patients suffering from pancreatic, prostate or breast cancer or incurable CRPC for whom new treatments are urgently needed.

Claims

Claims 1. An inhibitor of an aminoacyl-tRNA synthetase (AARS), for use in treating, preventing or ameliorating cancer.

2. The inhibitor, for use according to claim 1, wherein the aminoacyl-tRNA synthetase (AARS) is Aspartyl tRNA-synthetase (DARS), or Isoleucyl tRNA- synthetase (IARS).

3. The inhibitor, for use according to either claim 1 or claim 2, wherein the inhibitor is a small molecule, preferably wherein the small molecule is configured to inhibit an aminoacyl-tRNA synthetase (AARS).

4. The inhibitor, for use according to any preceding claim, wherein the inhibitor is an analogue of Aspartyl-adenylate.

5. The inhibitor, for use according to any preceding claim, wherein the inhibitor is 5’-O-[N-(L-Aspartyl)sulfamoyl]adenosine (Asp-AMS), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof.

6. The inhibitor, for use according to claim 5, wherein Asp-AMS has the formula (I): .to any preceding claim, wherein the inhibitor an or a acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof.

8. The inhibitor, for use according to claim 7, wherein the ester of Asp-AMS has the formula (IV):with a C6-C12aryl.

9. The inhibitor, use according to any preceding claim, wherein the inhibitor is Asp-AMS(OMe) or Asp-AMS(OBn), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof.

10. The inhibitor, for use according to claim 9, wherein: Asp-AMS(OMe) has the formula (II): ,Asp-AMS(OBn) has the formula (V): .

11. The inhibitor, for use according to any one of claims 1 to 3, wherein the inhibitor is an analogue of Isoleucyl-adenylate, preferably wherein the inhibitor is Ile-AMS, or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof.

12. The inhibitor, for use according to claim 11, wherein Ile-AMS has the formula (III): (III).

13. The inhibitor, for use according to either claim 1 or claim 2, wherein the inhibitor is an interfering nucleic acid molecule, preferably wherein the interfering nucleic acid molecule is configured to inhibit an aminoacyl-tRNA synthetase (AARS).

14. The inhibitor, for use according to claim 11, wherein the inhibitor is RNAi, preferably wherein the RNAi is microRNA (miRNA), small interfering RNA (siRNA) or short hairpin RNA (shRNA).

15. The inhibitor, for use according to either claim 13 or claim 14, wherein the inhibitor is siRNA.

16. The inhibitor, for use according to either claim 14 or claim 15, wherein the siRNA comprises a nucleic acid sequence as set out in SEQ ID No: 1, or a fragment or variant thereof.

17. The inhibitor, for use according to any preceding claim, wherein the cancer is a hormone-dependent cancer.

18. The inhibitor, for use according to claim 17, wherein the hormone- dependent cancer is a steroid hormone-driven cancer, an androgen-dependent cancer, an oestrogen-dependent cancer, or a progesterone-dependent cancer.

19. The inhibitor, for use according to claim 18, wherein: (i) the androgen-dependent cancer is prostate cancer; (ii) the oestrogen-dependent cancer is selected from a group consisting of: breast cancer, ovarian cancer, and endometrial (uterine) cancer; and / or (iii) the progesterone-dependent cancer is selected from a group consisting of: breast cancer and endometrial (uterine) cancer.

20. The inhibitor, for use according to any one of claims 17 to 19, wherein the hormone-dependent cancer is prostate cancer.

21. The inhibitor, for use according to claim 20, wherein the prostate cancer is castration-resistant prostate cancer, or AR-driven or androgen receptor positive aggressive form of prostate cancer.

22. The inhibitor, for use according to any one of claims 17 to 19, wherein the hormone-dependent cancer is breast cancer.

23. The inhibitor, for use according to any one of claims 1 to 16, wherein the cancer is pancreatic cancer.

24. A cancer prevention, treatment or amelioration pharmaceutical composition comprising a therapeutically effective amount of an inhibitor of an aminoacyl-tRNA synthetase (AARS), and a pharmaceutically acceptable vehicle.

25. A process for making the cancer prevention, treatment or amelioration pharmaceutical composition according to claim 24, the process comprising combining a therapeutically effective amount of the inhibitor of an aminoacyl-tRNA synthetase (AARS), with a pharmaceutically acceptable vehicle.

26. The composition according to claim 24, or the process according to claim 25, wherein the composition is a hormone-dependent cancer prevention, treatment or amelioration pharmaceutical composition.

27. The composition according to claim 24, or the process according to claim 25, wherein the composition is a pancreatic cancer prevention, treatment or amelioration pharmaceutical composition.

28. A compound of formula (IVa),wherein R1is a C1-C3 alkyl optionally substituted with a C6-C12 aryl, or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof.

29. A compound of formula (IV) or (IVa), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof, for use as a medicament.

30. A compound of formula (IV) or (IVa), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof, for use in treating, preventing or ameliorating cancer.

31. A pharmaceutical composition comprising a therapeutically effective amount of a compound comprising formula (IV) or (IVa), or a pharmaceutically acceptable salt, solvate, tautomeric form, stereoisomer or polymorphic form thereof, and a pharmaceutically acceptable vehicle.

32. A compound according to claim 28, a compound for use according to either claim 29 or claim 30, or a composition according to claim 31, wherein R1is a C1 alkyl.

33. A compound, a compound for use, or a composition according to claim 32, wherein the cancer is (i) prostate cancer; (ii) pancreatic cancer; and / or (ii) breast cancer, ovarian cancer, and endometrial (uterine) cancer.

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