Glutaminase inhibitor discovery and nanoparticle-enhanced delivery for cancer therapy

Abstract

Currently available glutaminase inhibitors are generally poorly soluble, metabolically unstable, and/or require high doses, which together reduce their efficacy and therapeutic index. These can be formulated into nanoparticles and delivered safely and effectively for treatment of pancreatic cancer and other glutamine addicted cancers. Studies demonstrate that nanoparticle delivery of BPTES, relative to use of BPTES alone, can be safely administered and provides dramatically improved tumor drug exposure, resulting in greater efficacy. GLS inhibitors can be administered in higher concentrations with sub-100 nm nanoparticles, since the nanoparticles package the drug into “soluble” colloidal nanoparticles, and the nanoparticles deliver higher drug exposure selectively to the tumors due to the enhanced permeability and retention (EPR) effect. These factors result in sustained drug levels above the IC50 within the tumors for days, providing significantly enhanced efficacy compared to unencapsulated drug.

1 . A nanoencapsulated glutaminase inhibitor formulated for administration to an individual for the treatment of a glutamine addicted cancer. 
     
     
         2 . The inhibitor of  claim 1  selected from the group consisting of a compound of Formula (1) 
       
         
           
           
               
               
           
         
         wherein R 1  is independently selected from hydrogen, C(═O)C 1-10  aliphatic, C(═O)OC 1-10  aliphatic and C 1-10  aliphatic; 
         Het is either absent or a substituted or unsubstituted heterocycle, 
         L is absent, or selected from —CH═CH—, —C≡C—, O, S, SO 2  or NR 1 ; 
         X represents —CH═CH—, O, S, SO 2  or NR 1    
         n is independently selected from 0-10; 
         R is in each case independently selected from hydrogen, C 1-10  aliphatic, alkoxy or hydroxy, or the two R groups on the same carbon atom may form an oxo, and wherein two or more R groups on the same or different carbon atoms may form a ring; 
         Y and Z independently represent substituted or unsubstituted alkyl, hydroxyalkyl, aminoalkyl, acylaminoalkyl, alkenyl, alkoxy, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, heteroaryloxyalkyl or C(R 8 )(R 9 )(R 10 ), N(R 4 )(R 5 )) or OR 5 , wherein any free hydroxyl group may be acylated to form C(═O)R 7 ; 
         R 4  and R 5  each independently for each occurrence represent hydrogen or substituted or unsubstituted alkyl, hydroxyalkyl, acyl, aminoalkyl, acylaminoalkyl, alkenyl, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, or heteroaryloxyalkyl, wherein any free hydroxyl group may be acylated to form C(═O)R 7 ; 
         R 7  represents substituted or unsubstituted alkyl, hydroxyalkyl, aminoalkyl, acylaminoalkyl, alkenyl, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, or heteroaryloxyalkyl, 
         R 8 , R 9  and R 10  each independently for each occurrence represent hydrogen or substituted or unsubstituted alkyl, hydroxy, hydroxyalkyl, amino, acylamino, aminoalkyl, acylaminoalkyl, alkoxycarbonyl, alkoxycarbonylamino, alkenyl, alkoxy, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, or heteroaryloxyalkyl, or R 8  and R 9  together with the carbon to which they are attached, form a carbocyclic or heterocyclic ring system, wherein any free hydroxyl group may be acylated to form C(═O)R 7 , and wherein at least two of R 8 , R 9  and R 10  are not hydrogen; 
         R 11  represents aryl, arylalkyl, aryloxy, aryloxyalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, or heteroaryloxyalkyl, wherein the aryl or heteroaryl ring is substituted with either —OCHF 2  or —OCF 3  and is optionally further substituted, or R 11  represents C(R 12 )(R 13 )(R 14 ), N(R 4 )(R 14 ) or OR 14 , wherein any free hydroxyl group may be acylated to form C(═O)R 7 ; 
         R 12  and R 13  each independently represent H or substituted or unsubstituted alkyl, hydroxy, hydroxyalkyl, amino, acylamino, aminoalkyl, acylaminoalkyl, alkoxycarbonyl, alkoxycarbonylamino, alkenyl, alkoxy, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, or heteroaryloxyalkyl, wherein any free hydroxyl group may be acylated to form C(═O)R 7 , and wherein both of R 12  and R 13  are not hydrogen; and 
         R 14  represents aryl, arylalkyl, aryloxy, aryloxyalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, or heteroaryloxyalkyl, wherein the aryl or heteroaryl ring is substituted with either —OCHF 2  or —OCF 3  and is optionally further substituted. 
       
     
     
         3 . The inhibitor of  claim 1  wherein the glutaminase inhibitor is a compound of Formula (2): 
       
         
           
           
               
               
           
         
         wherein AA represents an optionally protected amino acid group and Alk represents substituted or unsubstituted alkyl, hydroxyalkyl, aminoalkyl, acylaminoalkyl, alkenyl, alkoxy, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, heteroaryloxyalkyl or C(R 8 )(R 9 )(R 10 ), N(R 4 )(R 5 ) or OR 5 , wherein any free hydroxyl group may be acylated to form C(═O)R 7  wherein R 4 -R 10  have the above meanings given above. 
         or a compound of Formula (3): 
       
       
         
           
           
               
               
           
         
         wherein 
         Ar is an optionally substituted aryl ring; 
         R 1 , L, and Z have the meaning given above, and 
         Het 1  is an optionally substituted heterocyclic ring; 
         a and d are independently selected from 0-10; 
         b and c are independently selected from 0-5; 
         Het 2  is absent, or is an optionally substituted heterocyclic ring. 
       
     
     
         4 . The inhibitor of  claim 3  wherein Ar is an aryl ring selected from: 
       
         
           
           
               
               
           
         
         wherein 
       
       
         
           
           
               
               
           
         
       
       indicates that the ring system may be attached at any atom in the ring, m is selected from 0-3; and
 R is independently selected from a C 1-10  aliphatic group, a halogen, a hydroxyl, a trifluoromethyl group, an O—C 1-10  aliphatic group, a C(═O)O—C 1-10  aliphatic group, an OC(═O)—C 1-10  aliphatic group, a cyano, a nitro, NH 2 , NH(ali), N(ali) 2 , wherein (ali) represents a C 1-10  aliphatic group, and wherein in the case of N(ali) 2  the two aliphatic groups may form a ring, an azido, a thiol, an S—C 1-10  aliphatic group, a C 1-10  aliphatic-O—C 1-10  aliphatic group, a C1-10 aliphatic-C(═O)O—C 1-10  aliphatic group, a C 1-10  aliphatic-OC(═O)—C 1-10  aliphatic group, and a heterocyclic group. 
 
     
     
         5 . The inhibitor of  claim 1  selected from a compound of Formula (4) 
       
         
           
           
               
               
           
         
         wherein m, R, R 1  and R 5  have the meanings given above, and Q is either CH or N. 
       
     
     
         6 . The inhibitor of  claim 2  modified with a heterocycle selected from the group consisting of 1,2,4 thiadiazolyl, pyridazinyl, morpholinyl, pyrrolidinyl, imidazolyl, benzimidazolyl, tetrazolyl, 1,2,3 triazolyl, 1,2,4 triazolyl, isoxazolyl, and isothiazolyl, wherein each heterocycle may be substituted one or more times by OH, COOH, NH 2  or SH. 
     
     
         7 . The inhibitor of  claim 1  wherein the glutaminase inhibitor is acivicin, 6-diazo-5-oxo-L-norleucine, azaserine, ebselen, chelerythrine or apomorphine. 
     
     
         8 . The inhibitor of  claim 1  formulated in a hydrophobic polymer having a coating of a hydrophilic polymer selected from the group consisting of polyethylene glycol and polyoxyethylene glycol copolymers. 
     
     
         9 . The inhibitor of  claim 1  wherein the nanoparticles have a diameter of 100 nm or less. 
     
     
         10 . A method of inhibiting the growth of a glutamine addicted tumor comprising administering an effective amount of the inhibitor of  claim 1 . 
     
     
         11 . The method of  claim 10  wherein the cancer is pancreatic cancer. 
     
     
         12 . The method of  claim 10  wherein the inhibitor is administered systemically. 
     
     
         13 . The method of  claim 10  wherein the inhibitor is administered directly into the tumor. 
     
     
         14 . The method of  claim 10  comprising administering concurrently or sequentially other chemotherapeutics with the nanoparticulate inhibitor. 
     
     
         15 . The method of  claim 10  wherein the chemotherapeutics are selected from the group consisting of gemcitabine, taxols, capecitabine, erlotinib, 5-FU, Platinum analogs, fluoropyrimidine, and combinations thereof. 
     
     
         16 . The method of  claim 10  further comprising exposing the tumor to radiation. 
     
     
         17 . A compound of Formula (A): 
       
         
           
           
               
               
           
         
         wherein 
         R 1a -R 5a  are independently selected from hydrogen; halo, nitro, cyano, substituted or unsubstituted alkyl, hydroxy, hydroxyalkyl, amino, acylamino, aminoalkyl, acylaminoalkyl, alkoxycarbonyl, sulfonylalkyl, alkoxycarbonylamino, alkenyl, alkoxy, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, or heteroaryloxyalkyl 
         a, b and c are independently selected from 1-10; 
         R is selected from hydrogen, C(═O)C 1-10  aliphatic, C(═O)OC 1-10  aliphatic, C 1-10  aliphatic 
         L is absent, or selected from O, S, SO 2  or NR, —C≡C—, or optionally substituted alkenyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, aryl or heterocyclyl; 
         X is independently selected from O, S, NR, —R 1 C═CR 1 —; 
         R 1  is independently selected from hydrogen or substituted or unsubstituted alkyl, hydroxy, hydroxyalkyl, amino, acylamino, aminoalkyl, acylaminoalkyl, alkoxycarbonyl, alkoxycarbonylamino, alkenyl, alkoxy, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, or the two R 1  groups may together with the atoms to which they are attached, form a substituted or unsubstituted carbocyclic or heterocyclic ring system; 
         n is selected from 0 or 1; 
         Y is absent, a divalent aromatic heterocyclyl, or a divalent radical selected from: 
       
       
         
           
           
               
               
           
         
         Z is selected from COOH, substituted or unsubstituted heterocyclyl, or aryl of the following formula: 
       
       
         
           
           
               
               
           
         
         wherein R 1b -R 5b  are independently selected from hydrogen; halo, nitro, cyano, substituted or unsubstituted alkyl, hydroxy, hydroxyalkyl, amino, acylamino, aminoalkyl, acylaminoalkyl, alkoxycarbonyl, sufonylalkyl, alkoxycarbonylamino, alkenyl, alkoxy, alkoxyalkyl, aryl, arylalkyl, aryloxy, aryloxyalkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl, heteroaryloxy, or heteroaryloxyalkyl, 
       
       with the proviso that when c is 1, at least R 1a  is different than R 1b , R 2a  is different than R 2b , R 3a  is different than R 3b , R 4a  is different than R 4b , or R 5a  is different than R 5b . 
     
     
         18 . The compound according to  claim 17 , wherein each substituent is independently selected from C 1 -C 12  alkyl, C 2 -C 12  alkenyl, C 2 -C 12  alkynyl, C 6 -C 18  aryl, C 3 -C 12  cycloalkyl, C 1 -C 12  heterocyclyl, C 1 -C 18  heteroaryl, C 1 -C 12  alkoxy, C 1 -C 12  alkylamine, NR e   2 , NR e C(═O)R e , C(═O)NR e   2 , NR e C(═O)OR e , SR e , SO 2 R e , S(═O)R e , OH, OR e , C(═O)R e , COOH, C(═O)OR e , OC(═O)R e , OC(═O)OR e , CN, N═C═O, P(═O)R e , PO 3 R e   2 , halogen and NO 2 , wherein each R e  is independently selected from hydrogen or C 1-10  aliphatic, and wherein two R e  groups may form a ring. 
     
     
         19 . The compound according to  claim 17 , wherein R 1 -R 5  are each hydrogen. 
     
     
         20 . The compound according to  claim 17 , wherein Z is selected from COOH, or substituted or unsubstituted benzimidazolyl, benzofuranyl, benzothiofuranyl, benzothiophenyl, benzoxazolyl, benzoxazolinyl, benzthiazolyl, benztriazolyl, benztetrazolyl, benzisoxazolyl, benzisothiazolyl, benzimidazolinyl, carbazolyl, 4aH carbazolyl, carbolinyl, chromanyl, chromenyl, cinnolinyl, decahydroquinolinyl, 2H,6H-1,5,2-dithiazinyl, dihydrofuro[2,3 b]tetrahydrofuran, furanyl, furazanyl, imidazolidinyl, imidazolinyl, imidazolyl, 1H-indazolyl, indolenyl, indolinyl, indolizinyl, indolyl, 3H-indolyl, isatinoyl, isobenzofuranyl, isochromanyl, isoindazolyl, isoindolinyl, isoindolyl, isoquinolinyl, isothiazolyl, isoxazolyl, methylenedioxyphenyl, morpholinyl, naphthyridinyl, octahydroisoquinolinyl, oxadiazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl, oxazolidinyl, oxazolyl, oxindolyl, pyrimidinyl, phenanthridinyl, phenanthrolinyl, phenazinyl, phenothiazinyl, phenoxathinyl, phenoxazinyl, phthalazinyl, piperazinyl, piperidinyl, piperidonyl, 4-piperidonyl, piperonyl, pteridinyl, purinyl, pyranyl, pyrazinyl, pyrazolidinyl, pyrazolinyl, pyrazolyl, pyridazinyl, pyridooxazole, pyridoimidazole, pyridothiazole, pyridinyl, pyridyl, pyrimidinyl, pyrrolidinyl, pyrrolinyl, 2H-pyrrolyl, pyrrolyl, quinazolinyl, quinolinyl, 4H-quinolizinyl, quinoxalinyl, quinuclidinyl, tetrahydrofuranyl, tetrahydroisoquinolinyl, tetrahydroquinolinyl, tetrazolyl, 6H-1,2,5-thiadiazinyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl, thianthrenyl, thiazolyl, thienyl, thienothiazolyl, thienooxazolyl, thienoimidazolyl, thiophenyl, and xanthenyl. 
     
     
         21 . The compound according to  claim 20 , wherein Z is selected from COOH, 1,2,4 thiadiazolyl, pyridazinyl, morpholinyl, pyrrolidinyl, imidazolyl, benzimidazolyl, tetrazolyl, isoxazolyl, isothiazolyl, wherein each heterocycle may be substituted one or more times by OH, COOH, NH 2  or SH. 
     
     
         22 . The compound according to  claim 17 , wherein n is 0. 
     
     
         23 . The compound according to  claim 17 , wherein L is absent. 
     
     
         24 . The compound according to  claim 17 , wherein X is S. 
     
     
         25 . The compound according to  claim 17 , wherein Y is 
       
         
           
           
               
               
           
         
       
     
     
         26 . The compound according to  claim 17 , wherein Z is heterocyclyl, and c is 1. 
     
     
         27 . The compound according to  claim 17 , wherein Z is COOH. 
     
     
         28 . (canceled)