Inhibitors to Overcome Secondary Mutations in the Stem Cell Factor

Oct 9, 2017 - After culturing for 24 h in serum and antibiotics containing media in humidified chambers at 37 °C/5% CO2, the cells were incubated for...
35 downloads 8 Views 5MB Size
Article Cite This: J. Med. Chem. 2017, 60, 8801-8815

pubs.acs.org/jmc

Inhibitors to Overcome Secondary Mutations in the Stem Cell Factor Receptor KIT Helena Kaitsiotou,† Marina Keul,† Julia Hardick,† Thomas Mühlenberg,‡,§ Julia Ketzer,‡,§ Christiane Ehrt,† Jasmin Krüll,†,○ Federico Medda,∥,∇ Oliver Koch,† Fabrizio Giordanetto,∥,⊥ Sebastian Bauer,*,‡,§ and Daniel Rauh*,† †

Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Straße 4a, D-44227 Dortmund, Germany Department of Medical Oncology, Sarcoma Centre West German Cancer Centre University Duisburg−Essen, Medical School, Hufelandstraße 55, D-45122 Essen, Germany § Germany and German Cancer Consortium (DKTK), Partner Site University Hospital Essen, D-45147 Essen, Germany ∥ Taros Chemicals GmbH & Co. KG, Emil-Figge-Straße 76a, D-44227 Dortmund, Germany ‡

S Supporting Information *

ABSTRACT: In modern cancer therapy, the use of small organic molecules against receptor tyrosine kinases (RTKs) has been shown to be a valuable strategy. The association of cancer cells with dysregulated signaling pathways linked to RTKs represents a key element in targeted cancer therapies. The tyrosine kinase mast/stem cell growth factor receptor KIT is an example of a clinically relevant RTK. KIT is targeted for cancer therapy in gastrointestinal stromal tumors (GISTs) and chronic myelogenous leukemia (CML). However, acquired resistance mutations within the catalytic domain decrease the efficacy of this strategy and are the most common cause of failed therapy. Here, we present the structure-based design and synthesis of novel type II kinase inhibitors to overcome these mutations in KIT. Biochemical and cellular studies revealed promising molecules for the inhibition of mutated KIT.



INTRODUCTION KIT is a type III receptor tyrosine kinase that is an important signaling protein for the development of melanocytes, erythrocytes, germ cells, mast cells, and interstitial cells of cajal (gastrointestinal pacemaker cells).1−3 Upon binding of its ligand, stem cell factor (SCF), KIT activates downstream signaling pathways that promote cell survival and cell proliferation and inhibit apoptosis.4 Constitutive activation of KIT as an oncogenic driver has first been described in feline sarcomas (“kitten”-KIT) but was later also found in a variety of human cancers including melanomas,5,6 seminomas, acute myeloid leukemias, systemic mastocytosis, sinonasal lymphoma, and gastrointestinal stromal tumors (GIST).7,8 Particularly, GISTs have since then become a paradigm of successful targeted treatment for cancer. GIST represents the most common mesenchymal tumor of the gastrointestinal tract,9−11 and approximately 85% of GISTs harbor oncogenic gain-of-function mutations of KIT or the platelet-derived growth factor receptor (PDGFR).12,13 Activating mutations of KIT represent an early oncogenic event, but KIT also remains the central oncogenic driver in patients with highly advanced GIST disease.7,14,15 Primary, activating mutations of KIT in GIST most commonly occur within the juxtamembrane (exon 11) and the extracellular regions (exon 9) and only very rarely in other exons (8, 13, 17).16−19 Three © 2017 American Chemical Society

inhibitors of KIT have until now been approved for the treatment of GIST. Of note, these three inhibitors had been primarily developed as inhibitors of kinases other than KIT such as BCR-ABL (1 (imatinib) 20 ) and VEGFR (2 (sunitinib),21 and 3 (regorafenib)22) (Figure 1).23−26 The possibility of inhibiting dysregulated tyrosine kinases in kinase mutation-driven cancer has led to the development of tyrosine kinase inhibitor (TKI) therapies. In many cases, TKIs have been shown to be more beneficial than traditional cancer treatments in terms of side effects and the overall clinical outcomes for patients with GIST.17,18 1, a 2-phenylaminopyrimidine derivative, is a rapidly absorbed oral kinase inhibitor that effectively inhibits exon 9 and exon 11 KIT mutants and whose response rates, as well as duration of clinical benefit, correlate with genotype.27,28 Long lasting disease control (median progression-free survival [PFS] exon 11:2.3 years; exon 9:1.6 years)29 paired with a favorable side effect profile have made 1 the standard first-line treatment. Nonetheless, the majority of patients eventually progress and secondary mutations within the ATP-binding pocket (exon 13, V654A; exon 14, T670I) and the activation loop (affecting codons 816−829) represent the major mechanisms of resistance.30,31 Received: June 8, 2017 Published: October 9, 2017 8801

DOI: 10.1021/acs.jmedchem.7b00841 J. Med. Chem. 2017, 60, 8801−8815

Journal of Medicinal Chemistry

Article

Figure 1. (A) Structural alignment of kinase inhibitors, approved by the FDA for the treatment of GIST, bound to wild-type KIT (pdb 4u0i) (1 (green, pdb 4bkj), 2 (yellow, pdb 3g0e), 3 (blue, modeled), and 4 (red, pdb 4u0i)). Unique substitution patterns and hinge binding elements of the inhibitors highlighted (right). (B) X-ray crystal structure of 4 in complex with wild-type KIT (pdb 4u0i) with modeled secondary mutations (sticks and surfaces). Hydrogen bonds are depicted by blue dotted lines.

hypertension-related side effects. Compared to the substantial benefits obtained with 1 as first-line treatment, the clinical benefits of 2 and 3 are moderate, and the side effect profiles of both inhibitors are much less favorable than those of 1.35−38 Currently, (S)-1-(4-fluorophenyl)-1-(2-(4-(6-(1-methyl-1Hpyrazol-4-yl)pyrrolo[2,1-f ][1,2,4]triazin-4-yl)piperazin-1-yl)pyrimidin-5-yl)ethan-1-amine39 ((BLU-285) (NCT02508532)), a potent inhibitor of PDGFRA-D842 and KIT exon 17 mutations and 1-N′-[2,5-difluoro-4-[2-(1methylpyrazol-4-yl)pyridine-4-yl]oxyphenyl]-1-N-phenylcyclopropane-1,1-dicarboxamide40 ((DCC-2618) (NCT02571036)), a type III inhibitor of KIT and PDGFRA, and PLX9486/PLX339741 (NCT02401815) represent the first wave of novel compounds that were designed especially for KIT to exhibit strong activity against exon 13/14 and 17, which is not only important for GIST but also for KIT-driven leukemias and melanomas.42 4 (ponatinib) is a next-generation, highly potent ATP-competitive inhibitor of BCR-ABL, which was rationally designed to inhibit the notoriously resistant T315I mutation.43,44 Approval was granted for the treatment of

Both 2 and 3 show better activity against KIT mutants with secondary resistance mutations, and approval was granted based on an improved median PFS of 4−5 months over placebo in second-32 and third-line treatment.33 However, response rates for both drugs are low (95% purity was conducted by high-performance liquid chromatography (HPLC). The purity was determined using Agilent 1200 series HPLC systems with UV detection at 210 nm (system: Agilent Eclipse XDB-C18 4.6 mm × 150 mm, 5 μM, 10−100% CH3CN in H2O, with 0.1% TFA, for 15 min at 1.0 mL/min). Reagents and Materials. All supplies for the KIT HTRF assay kit were purchased from CisBio (Bagnols-sur-Cèze, France). Small volume (20 μL fill volume) white round-bottom 384-well plates were obtained from Greiner Bio-One GmbH (Solingen, Germany). Activity-Based Assay for IC50 Determination. IC50 determinations for KIT kinases were measured with the KinEASE-TK assay from Cisbio according to the manufacturer’s instructions. A biotinylated poly-Glu-Tyr substrate peptide was phosphorylated by the specific kinase of interest. After completion of the reaction, an antiphosphotyrosine antibody labeled with europium cryptate and streptavidin labeled with the fluorophore XL665 were added. FRET between europium cryptate and XL665 was measured to quantify the phosphorylation of the substrate peptide. ATP concentrations were set at their respective KM values (30 μM for wild-type KIT, 20 μM for KIT V559D/T670I, 12 μM for KIT D816H, and 50 μM for V559D/ V654A). A substrate concentration of 330 nM was used for KIT wildtype, 450 nM was used for KIT V559D/T670I, 1 μM was used for KIT D816H and 1 μM was used for KIT V559D/V654A, respectively. Kinase and inhibitor were preincubated for 30 min before the reaction was started by addition of ATP and substrate peptide. A PerkinElmer EnVision multimode plate reader was used to measure the fluorescence of the samples at 620 nm (Eu-labeled antibody) and 665 nm (XL665 labeled streptavidin) 50 μs after excitation at 320 nm. The quotient of both intensities for reactions at eight different inhibitor concentrations was then analyzed using the Quattro software suite for IC50 value determination. Each reaction was performed in duplicate, and at least three independent determinations of each IC50 were made. Gist Cell Lines. GIST-T1 and GIST-T1 T670I were cultured in DMEM (Gibco), and GIST430-V654A, GIST-T1-D816E, and GIST48B were cultured in IMDM (Gibco), supplemented with 10−15% FBS (Biochrome) and 1% Pen/Step/Ampho (Gibco). GIST430V654A, GIST-T1-T670I, and GIST-D816E Media were supplemented with 1 100 nM, 200 nM, and 1 μM, respectively. GIST-T1 was established (by Takahiro Taguchi, Kochi University, Japan) from a 8812

DOI: 10.1021/acs.jmedchem.7b00841 J. Med. Chem. 2017, 60, 8801−8815

Journal of Medicinal Chemistry



plasma ( f u50%) is extrapolated to the fraction unbound at 100% plasma (f u100%) using the following equation: f u100% = f u50%/(2 − f u50%) Caco-2 Assay. To measure cellular permeability, compounds were applied at a concentration of 10 μM in HBSS to either the apical (A) or basolateral (B) side of a Caco-2 cell monolayer and incubated for 2 h at 37 °C. Compound concentrations on each side of the monolayer were determined by LC-MS/MS and the apparent permeability (Papp) was calculated in the apical to basolateral (A → B) and basolateral to apical (B → A) directions according to the following equation: Papp(A → B) = (ΔCB × VB × 0.001)/(Δt × A × Ct0,A).



ACKNOWLEDGMENTS

This work was cofunded by the German Federal Ministry for Education and Research (NGFNPlus and e:Med) (grant no. BMBF 01GS08104, 01ZX1303C) and by the Deutsche Forschungsgemeinschaft (DFG). D.R. thanks the German federal state North Rhine Westphalia (NRW) and the European Union (European Regional Development Fund: Investing In Your Future) (EFRE-800400). C.E. is funded by the Kekulé Mobility Fellowship of the Chemical Industry Fund (FCI). O.K. is funded by the German Federal Ministry for Education and Research (BMBF, Medizinische Chemie in Dortmund, grant BMBF 1316053).

ASSOCIATED CONTENT

S Supporting Information *



The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jmedchem.7b00841. RMSD profiles for the MD simulations of wild-type KIT, KITT670I, and KITV654A in the presence and absence of ponatinib; RMSF values of the active site of wild-type KIT, KITT670I, and KITV654A; angle between the axis of the α helix C and the unit cell vector x during a 300 ns MD simulation; kinome dendrogram derived from the SelectScreen; Analysis of the ponatinib binding site volume for the MD simulations in the absence of ponatinib; PCA results for the MD simulations in the absence of ponatinib; data of the SelectScreen; in vitro intrinsic clearance CLint in human and murine liver microsomes; relative compound degradation of 7f, 10, ponatinib, imatinib, and regorafenib; pharmacokinetic parameters of 7f, 10, ponatinib, imatinib, and regorafenib; results of the RMSD-based binding site clustering analyses; hydrogen bond occupancies for the MD simulations with ponatinib; free energies of binding as estimated by MM-PB(GB)SA calculations; binding site comparison results; detailed synthetic procedures for the preparation of inhibitors for KIT mutants (PDF) Molecular formula strings (CSV)



Article

ABBREVIATIONS USED KIT, mast/stem cell growth factor receptor kinase; VEGFR, vascular endothelial growth factor receptor; GIST, gastrointestinal stromal tumors; RTK, receptor tyrosine kinase; SAR, structure−activity relationship: relationship between the chemical structure of a molecule and its biological activity on a target; TKI, tyrosine kinase inhibitor; MD, molecular dynamics; GI50, concentration for 50% of maximal inhibition of cell proliferation; IC50, concentration causing 50% inhibition of enzyme activity; PCA, principle component analysis; MMPB(GB)SA, molecular mechanics Poisson−Boltzmann (Generalized Born) solvent-accessible surface area; R-spine regulatory spine, highly conserved motif, found in every active kinase



REFERENCES

(1) Tsujimura, T.; Furitsu, T.; Morimoto, M.; Isozaki, K.; Nomura, S.; Matsuzawa, Y.; Kitamura, Y.; Kanakura, Y. Ligand-independent activation of c-kit receptor tyrosine kinase in a murine mastocytoma cell-line p-815 generated by a point mutation. Blood 1994, 83, 2619− 2626. (2) Tsujimura, T.; Furitsu, T.; Morimoto, M.; Kanayama, Y.; Nomura, S.; Matsuzawa, Y.; Kitamura, Y.; Kanakura, Y. Substitution of an aspartic acid results in constitutive activation of c-kit receptor tyrosine kinase in a rat tumor mast cell line rbl-2h3. Int. Arch. Allergy Immunol. 2004, 106, 377−385. (3) Furitsu, T.; Tsujimura, T.; Tono, T.; Ikeda, H.; Kitayama, H.; Koshimizu, U.; Sugahara, H.; Butterfield, J. H.; Ashman, L. K.; Kanayama, Y.; Matsuzawa, Y.; Kitamura, Y.; Kanakura, Y. Identification of mutations in the coding sequence of the protooncogene c-kit in a human mast-cell leukemia-cell line causing ligand-independent activation of c-kit product. J. Clin. Invest. 1993, 92, 1736−1744. (4) Linnekin, D. Early signaling pathways activated by c-kit in hematopoietic cells. Int. J. Biochem. Cell Biol. 1999, 31, 1053−1074. (5) Carvajal, R. D.; Lawrence, D. P.; Weber, J. S.; Gajewski, T. F.; Gonzalez, R.; Lutzky, J.; O’Day, S. J.; Hamid, O.; Wolchok, J. D.; Chapman, P. B.; Sullivan, R. J.; Teitcher, J. B.; Ramaiya, N.; GiobbieHurder, A.; Antonescu, C. R.; Heinrich, M. C.; Bastian, B. C.; Corless, C. L.; Fletcher, J. A.; Hodi, F. S. Phase ii study of nilotinib in melanoma harboring kit alterations following progression to prior kit inhibition. Clin. Cancer Res. 2015, 21, 2289−2296. (6) Curtin, J. A.; Busam, K.; Pinkel, D.; Bastian, B. C. Somatic activation of kit in distinct subtypes of melanoma. J. Clin. Oncol. 2006, 24, 4340−4246. (7) Ashman, L. K.; Griffith, R. Therapeutic targeting of c-kit in cancer. Expert Opin. Invest. Drugs 2013, 22, 103−115. (8) Abbaspour Babaei, M.; Kamalidehghan, B.; Saleem, M.; Huri, H. Z.; Ahmadipour, F. Receptor tyrosine kinase (c-kit) inhibitors: A potential therapeutic target in cancer cells. Drug Des., Dev. Ther. 2016, 10, 2443−2459. (9) Poveda, A.; Martinez, V.; Serrano, C.; Sevilla, I.; Lecumberri, M. J.; de Beveridge, R. D.; Estival, A.; Vicente, D.; Rubió, J.; Martin-Broto,

AUTHOR INFORMATION

Corresponding Authors

*For D.R.: phone, +49 (0)231-755-7080; fax, +49 (0)231-7557082; E-mail, [email protected]. *For S.B.: phone, +49 (0) 201-723-2112; fax, +49 (0) 201-2015996; E-mail, [email protected]. ORCID

Daniel Rauh: 0000-0002-1970-7642 Present Addresses ⊥

For F.G.: D. E. Shaw Research, 120 West 45th Street, 39th Floor, New York, New York 10036, United States. ∇ For F.M.: CytRx Corporation Drug Discovery Branch, Engesserstraße 4, 79108 Freiburg, Germany. ○ For J.K.: Department of Chemistry and Pharmacy, University Erlangen−Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany. Author Contributions

The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript. Notes

The authors declare no competing financial interest. 8813

DOI: 10.1021/acs.jmedchem.7b00841 J. Med. Chem. 2017, 60, 8801−8815

Journal of Medicinal Chemistry

Article

expressing bcr-abl, tel-abl, and tel-pdgfr fusion proteins. Blood 1997, 90, 4947−4952. (27) Pogorzelski, M.; Falkenhorst, J.; Bauer, S. Molecular subtypes of gastrointestinal stromal tumor requiring specific treatments. Curr. Opin. Oncol. 2016, 28, 331−337. (28) Heinrich, M. C.; Owzar, K.; Corless, C. L.; Hollis, D.; Borden, E. C.; Fletcher, C. D.; Ryan, C. W.; Von Mehren, M.; Blanke, C. D.; Rankin, C.; Benjamin, R. S.; Bramwell, V. H.; Demetri, G. D.; Bertagnolli, M. M.; Fletcher, J. A. Correlation of kinase genotype and clinical outcome in the north American intergroup phase iii trial of imatinib mesylate for treatment of advanced gastrointestinal stromal tumor: Calgb 150105 study by cancer and leukemia group b and southwest oncology group. J. Clin. Oncol. 2008, 26, 5360−5367. (29) Debiec-Rychter, M.; Sciot, R.; Le Cesne, A.; Schlemmer, M.; Hohenberger, P.; van Oosterom, A. T.; Blay, J. Y.; Leyvraz, S.; Stul, M.; Casali, P. G.; Zalcberg, J.; Verweij, J.; Van Glabbeke, M.; Hagemeijer, A.; Judson, I. Kit mutations and dose selection for imatinib in patients with advanced gastrointestinal stromal tumours. Eur. J. Cancer 2006, 42, 1093−1103. (30) Heinrich, M. C.; Corless, C. L.; Blanke, C. D.; Demetri, G. D.; Joensuu, H.; Roberts, P. J.; Eisenberg, B. L.; Von Mehren, M.; Fletcher, C. D.; Sandau, K.; McDougall, K.; Ou, W. B.; Chen, C. J.; Fletcher, J. A. Molecular correlates of imatinib resistance in gastrointestinal stromal tumors. J. Clin. Oncol. 2006, 24, 4764−4774. (31) Blanke, C. D.; Demetri, G. D.; Von Mehren, M.; Heinrich, M. C.; Eisenberg, B.; Fletcher, J. A.; Corless, C. L.; Fletcher, C. D.; Roberts, P. J.; Heinz, D.; Wehre, E.; Nikolova, Z.; Joensuu, H. Longterm results from a randomized phase ii trial of standard- versus higher-dose imatinib mesylate for patients with unresectable or metastatic gastrointestinal stromal tumors expressing kit. J. Clin. Oncol. 2008, 26, 620−625. (32) Demetri, G. D.; van Oosterom, A. T.; Garrett, C. R.; Blackstein, M. E.; Shah, M. H.; Verweij, J.; McArthur, G.; Judson, I. R.; Heinrich, M. C.; Morgan, J. A.; Desai, J.; Fletcher, C. D.; George, S.; Bello, C. L.; Huang, X.; Baum, C. M.; Casali, P. G. Efficacy and safety of sunitinib in patients with advanced gastrointestinal stromal tumour after failure of imatinib: A randomised controlled trial. Lancet 2006, 368, 1329− 1338. (33) Demetri, G. D.; Reichardt, P.; Kang, Y. K.; Blay, J. Y.; Rutkowski, P.; Gelderblom, H.; Hohenberger, P.; Leahy, M.; von Mehren, M.; Joensuu, H.; Badalamenti, G.; Blackstein, M.; Le Cesne, A.; Schöffski, P.; Maki, R. G.; Bauer, S.; Nguyen, B. B.; Xu, J.; Nishida, T.; Chung, J.; Kappeler, C.; Kuss, I.; Laurent, D.; Casali, P. G. Efficacy and safety of regorafenib for advanced gastrointestinal stromal tumours after failure of imatinib and sunitinib (grid): An international, multicentre, randomised, placebo-controlled, phase 3 trial. Lancet 2013, 381, 295−302. (34) Garner, A. P.; Gozgit, J. M.; Anjum, R.; Vodala, S.; Schrock, A.; Zhou, T.; Serrano, C.; Eilers, G.; Zhu, M.; Ketzer, J.; Wardwell, S.; Ning, Y.; Song, Y.; Kohlmann, A.; Wang, F.; Clackson, T.; Heinrich, M. C.; Fletcher, J. A.; Bauer, S.; Rivera, V. M. Ponatinib inhibits polyclonal drug-resistant kit oncoproteins and shows therapeutic potential in heavily pretreated gastrointestinal stromal tumor (gist) patients. Clin. Cancer Res. 2014, 20, 5745−5755. (35) Bauer, S.; Joensuu, H. Emerging agents for the treatment of advanced, imatinib-resistant gastrointestinal stromal tumors: Current status and future directions. Drugs 2015, 75, 1323−1334. (36) Demetri, G. D.; Reichardt, P.; Kang, Y. K.; Blay, J. Y.; Rutkowski, P.; Gelderblom, H.; Hohenberger, P.; Leahy, M.; von Mehren, M.; Joensuu, H.; Badalamenti, G.; Blackstein, M.; Le Cesne, A.; Schoffski, P.; Maki, R. G.; Bauer, S.; Nguyen, B. B.; Xu, J.; Nishida, T.; Chung, J.; Kappeler, C.; Kuss, I.; Laurent, D.; Casali, P. G.; GRID study investigators. Efficacy and safety of regorafenib for advanced gastrointestinal stromal tumours after failure of imatinib and sunitinib (grid): An international, multicentre, randomised, placebo-controlled, phase 3 trial. Lancet 2013, 381, 295−302. (37) Wu, L.; Zhang, Z.; Yao, H.; Liu, K.; Wen, Y.; Xiong, L. Clinical efficacy of second-generation tyrosine kinase inhibitors in imatinib-

J. Seom clinical guideline for gastrointestinal sarcomas (gist) (2016). Clin. Transl. Oncol. 2016, 18, 1221−1228. (10) Antonescu, C. R. The GIST paradigm: Lessons for other kinasedriven cancers. J. Pathol. 2011, 223, 252−262. (11) Søreide, K.; Sandvik, O. M.; Søreide, J. A.; Giljaca, V.; Jureckova, A.; Bulusu, V. R. Global epidemiology of gastrointestinal stromal tumours (gist): A systematic review of population-based cohort studies. Cancer Epidemiol. 2016, 40, 39−46. (12) Hirota, S.; Isozaki, K.; Moriyama, Y.; Hashimoto, K.; Nishida, T.; Ishiguro, S.; Kawano, K.; Hanada, M.; Kurata, A.; Takeda, M.; Muhammad, T. G.; Matsuzawa, Y.; Kanakura, Y.; Shinomura, Y.; Kitamura, Y. Gain-of-function mutations of c-kit in human gastrointestinal stromal tumors. Science 1998, 279, 577−580. (13) Heinrich, M. C.; Corless, C. L.; Duensing, A.; McGreevey, L.; Chen, C. J.; Joseph, N.; Singer, S.; Griffith, D. J.; Haley, A.; Town, A.; Demetri, G. D.; Fletcher, C. D.; Fletcher, J. A. PDGFRA activating mutations in gastrointestinal stromal tumors. Science 2003, 299, 708− 710. (14) Corless, C. L.; McGreevey, L.; Haley, A.; Town, A.; Heinrich, M. C. Kit mutations are common in incidental gastrointestinal stromal tumors one centimeter or less in size. Am. J. Pathol. 2002, 160, 1567− 1572. (15) Verweij, J.; Casali, P. G.; Zalcberg, J.; LeCesne, A.; Reichardt, P.; Blay, J. Y.; Issels, R.; van Oosterom, A.; Hogendoorn, P. C.; Van Glabbeke, M.; Bertulli, R.; Judson, I. Progression-free survival in gastrointestinal stromal tumours with high-dose imatinib: Randomised trial. Lancet 2004, 364, 1127−1134. (16) Corless, C. L.; Barnett, C. M.; Heinrich, M. C. Gastrointestinal stromal tumours: Origin and molecular oncology. Nat. Rev. Cancer 2011, 11, 865−878. (17) Jensen, B. M.; Akin, C.; Gilfillan, A. M. Pharmacological targeting of the kit growth factor receptor: A therapeutic consideration for mast cell disorders. Br. J. Pharmacol. 2008, 154, 1572−82. (18) Gramza, A. W.; Corless, C. L.; Heinrich, M. C. Resistance to tyrosine kinase inhibitors in gastrointestinal stromal tumors. Clin. Cancer Res. 2009, 15, 7510−7518. (19) Joensuu, H.; Hohenberger, P.; Corless, C. L. Gastrointestinal stromal tumour. Lancet 2013, 382, 973−983. (20) Zimmermann, J. Pyrimidin derivatives and process for their preparation. EP0564409B1, 19.01.2000, 2000. (21) Sun, C. L.; Wei, C. C.; Tang, P. C.; Koenig, M.; Zhou, Y.; Vojkovsky, T.; Nematalla, A. S. Prodrugs of a 3-(pyrrolo-2ylmethylidene)-2-indolinobne derivatives. US 2003/0100555 A1, 29.05.2003, 2003. (22) Boyer, S.; Dumas, J.; Phillips, B.; Scott, W. J.; Smith, R. A.; Chen, J.; Jones, B.; Wang, G. 2-Oxo-1,3,5-perhydrotriazapine derivatives useful in the treatment of hyper-proliferative, angiogenesis, and inflammatory disorders. WO2004078746 A3, 01.03.2004, 2004. (23) Buchdunger, E.; Cioffi, C. L.; Law, N.; Stover, D.; Ohno-Jones, S.; Druker, B. J.; Lydon, N. B. Abl protein-tyrosine kinase inhibitor sti571 inhibits in vitro signal transduction mediated by c-kit and platelet-derived growth factor receptors. J. Pharmacol. Exp. Ther. 2000, 295, 139−145. (24) Sun, L.; Liang, C.; Shirazian, S.; Zhou, Y.; Miller, T.; Cui, J.; Fukuda, J. Y.; Chu, J. Y.; Nematalla, A.; Wang, X.; Chen, H.; Sistla, A.; Luu, T. C.; Tang, F.; Wei, J.; Tang, C. Discovery of 5-[5-fluoro-2-oxo1,2- dihydroindol-(3z)-ylidenemethyl]-2,4- dimethyl-1h-pyrrole-3-carboxylic acid (2-diethylaminoethyl)amide, a novel tyrosine kinase inhibitor targeting vascular endothelial and platelet-derived growth factor receptor tyrosine kinase. J. Med. Chem. 2003, 46, 1116−1119. (25) Wilhelm, S. M.; Dumas, J.; Adnane, L.; Lynch, M.; Carter, C. A.; Schutz, G.; Thierauch, K. H.; Zopf, D. Regorafenib (bay 73−4506): A new oral multikinase inhibitor of angiogenic, stromal and oncogenic receptor tyrosine kinases with potent preclinical antitumor activity. Int. J. Cancer 2011, 129, 245−255. (26) Carroll, M.; Ohno-Jones, S.; Tamura, S.; Buchdunger, E.; Zimmermann, J.; Lydon, N. B.; Gilliland, D. G.; Druker, B. J. CGP 57148, a tyrosine kinase inhibitor, inhibits the growth of cells 8814

DOI: 10.1021/acs.jmedchem.7b00841 J. Med. Chem. 2017, 60, 8801−8815

Journal of Medicinal Chemistry

Article

Conformational changes in protein kinases. Arch. Pharm. (Weinheim, Ger.) 2010, 343, 193−206. (54) Taylor, S. S.; Kornev, A. P. Protein kinases: Evolution of dynamic regulatory proteins. Trends Biochem. Sci. 2011, 36, 65−77. (55) Kornev, A. P.; Haste, N. M.; Taylor, S. S.; Ten Eyck, L. F. Surface comparison of active and inactive protein kinases identifies a conserved activation mechanism. Proc. Natl. Acad. Sci. U. S. A. 2006, 103, 17783−17788. (56) Quintás-Cardama, A.; Kantarjian, H.; Cortes, J. Flying under the radar: The new wave of bcr-abl inhibitors. Nat. Rev. Drug Discovery 2007, 6, 834−848. (57) DiNitto, J. P.; Wu, J. C. Molecular mechanisms of drug resistance in tyrosine kinases cabl and ckit. Crit. Rev. Biochem. Mol. Biol. 2011, 46, 295−309. (58) Mol, C. D.; Dougan, D. R.; Schneider, T. R.; Skene, R. J.; Kraus, M. L.; Scheibe, D. N.; Snell, G. P.; Zou, H.; Sang, B. C.; Wilson, K. P. Structural basis for the autoinhibition and sti-571 inhibition of c-kit tyrosine kinase. J. Biol. Chem. 2004, 279, 31655−31663. (59) Lambert, G. K.; Duhme-Klair, A. K.; Morgan, T.; Ramjee, M. K. The background, discovery and clinical development of bcr-abl inhibitors. Drug Discovery Today 2013, 18, 992−1000. (60) Doroshow, J. H. Overcoming resistance to targeted anticancer drugs. N. Engl. J. Med. 2013, 369, 1852−1853. (61) Rey, J. B.; Launay-Vacher, V.; Tournigand, C. Regorafenib as a single-agent in the treatment of patients with gastrointestinal tumors: An overview for pharmacists. Target Oncol. 2015, 10, 199−213. (62) Guo, T.; Agaram, N. P.; Wong, G. C.; Hom, G.; D’Adamo, D.; Maki, R. G.; Schwartz, G. K.; Veach, D.; Clarkson, B. D.; Singer, S.; DeMatteo, R. P.; Besmer, P.; Antonescu, C. R. Sorafenib inhibits the imatinib-resistant kitt670i gatekeeper mutation in gastrointestinal stromal tumor. Clin. Cancer Res. 2007, 13, 4874−4881. (63) Taguchi, T.; Sonobe, H.; Toyonaga, S.; Yamasaki, I.; Shuin, T.; Takano, A.; Araki, K.; Akimaru, K.; Yuri, K. Conventional and molecular cytogenetic characterization of a new human cell line, gistt1, established from gastrointestinal stromal tumor. Lab. Invest. 2002, 82, 663−665. (64) Tomassi, S.; Lategahn, J.; Engel, J.; Keul, M.; Tumbrink, H. L.; Ketzer, J.; Mühlenberg, T.; Baumann, M.; Schultz-Fademrecht, C.; Bauer, S.; Rauh, D. Indazole-based covalent inhibitors to target drugresistant epidermal growth factor receptor. J. Med. Chem. 2017, 60, 2361−2372.

resistant gastrointestinal stromal tumors: A meta-analysis of recent clinical trials. Drug Des., Dev. Ther. 2014, 8, 2061−2067. (38) Nishida, T.; Blay, J. Y.; Hirota, S.; Kitagawa, Y.; Kang, Y. K. The standard diagnosis, treatment, and follow-up of gastrointestinal stromal tumors based on guidelines. Gastric Cancer 2016, 19, 3−14. (39) Zhang, Y.; Hodous, B. L.; Kim, J. L.; Wilson, K. J.; Wilson, D. Compositions useful for treating disorders related to kit. WO2015/ 057873, 2017. (40) Flynn, D. L.; Petillo, P. A.; Kaufman, M. D. Cyclopropane amides and analogs exhibiting anti-cancer and anti-proliferative activities. US 8278331, 2013. (41) Plx9486 ± plx3397; Plexxikon: San Antonio, TX, 2017; http:// www.plexxikon.com/pipeline/plx9486-plx3397/ (accessed September 10, 2017). (42) BLU-285, DCC-2618 show activity against gist. Cancer Discovery 2017, 7, 121−122, 10.1158/2159-8290.CD-NB2016-165. (43) O’Hare, T.; Shakespeare, W. C.; Zhu, X.; Eide, C. A.; Rivera, V. M.; Wang, F.; Adrian, L. T.; Zhou, T.; Huang, W. S.; Xu, Q.; Metcalf, C. A., III; Tyner, J. W.; Loriaux, M. M.; Corbin, A. S.; Wardwell, S.; Ning, Y.; Keats, J. A.; Wang, Y.; Sundaramoorthi, R.; Thomas, M.; Zhou, D.; Snodgrass, J.; Commodore, L.; Sawyer, T. K.; Dalgarno, D. C.; Deininger, M. W.; Druker, B. J.; Clackson, T. Ap24534, a pan-bcrabl inhibitor for chronic myeloid leukemia, potently inhibits the t315i mutant and overcomes mutation-based resistance. Cancer Cell 2009, 16, 401−412. (44) Huang, W. S.; Metcalf, C. A.; Sundaramoorthi, R.; Wang, Y.; Zou, D.; Thomas, R. M.; Zhu, X.; Cai, L.; Wen, D.; Liu, S.; Romero, J.; Qi, J.; Chen, I.; Banda, G.; Lentini, S. P.; Das, S.; Xu, Q.; Keats, J.; Wang, F.; Wardwell, S.; Ning, Y.; Snodgrass, J. T.; Broudy, M. I.; Russian, K.; Zhou, T.; Commodore, L.; Narasimhan, N. I.; Mohemmad, Q. K.; Iuliucci, J.; Rivera, V. M.; Dalgarno, D. C.; Sawyer, T. K.; Clackson, T.; Shakespeare, W. C. Discovery of 3-[2(imidazo[1,2-b]pyridazin-3-yl)ethynyl]-4-methyl-n-{4-[(4-methylpiperazin-1-y l)methyl]-3-(trifluoromethyl)phenyl}benzamide (ap24534), a potent, orally active pan-inhibitor of breakpoint cluster region-abelson (bcr-abl) kinase including the t315i gatekeeper mutant. J. Med. Chem. 2010, 53, 4701−4719. (45) Cortes, J. E.; Kantarjian, H.; Shah, N. P.; Bixby, D.; Mauro, M. J.; Flinn, I.; O’Hare, T.; Hu, S.; Narasimhan, N. I.; Rivera, V. M.; Clackson, T.; Turner, C. D.; Haluska, F. G.; Druker, B. J.; Deininger, M. W.; Talpaz, M. Ponatinib in refractory philadelphia chromosomepositive leukemias. N. Engl. J. Med. 2012, 367, 2075−2088. (46) Dorer, D. J.; Knickerbocker, R. K.; Baccarani, M.; Cortes, J. E.; Hochhaus, A.; Talpaz, M.; Haluska, F. G. Impact of dose intensity of ponatinib on selected adverse events: Multivariate analyses from a pooled population of clinical trial patients. Leuk. Res. 2016, 48, 84−91. (47) Jain, P.; Kantarjian, H.; Jabbour, E.; Gonzalez, G. N.; Borthakur, G.; Pemmaraju, N.; Daver, N.; Gachimova, E.; Ferrajoli, A.; Kornblau, S.; Ravandi, F.; O’Brien, S.; Cortes, J. Ponatinib as first-line treatment for patients with chronic myeloid leukaemia in chronic phase: A phase 2 study. Lancet Haematol. 2015, 2, e376−e383. (48) Azam, M.; Seeliger, M. A.; Gray, N. S.; Kuriyan, J.; Daley, G. Q. Activation of tyrosine kinases by mutation of the gatekeeper threonine. Nat. Struct. Mol. Biol. 2008, 15, 1109−1118. (49) Barouch-Bentov, R.; Sauer, K. Mechanisms of drug resistance in kinases. Expert Opin. Invest. Drugs 2011, 20, 153−208. (50) Richters, A.; Ketzer, J.; Getlik, M.; Grütter, C.; Schneider, R.; Heuckmann, J. M.; Heynck, S.; Sos, M. L.; Gupta, A.; Unger, A.; Schultz-Fademrecht, C.; Thomas, R. K.; Bauer, S.; Rauh, D. Targeting gain of function and resistance mutations in abl and kit by hybrid compound design. J. Med. Chem. 2013, 56, 5757−5772. (51) Batista, J. H.; Hawkins, P. C. D.; Tolbert, R.; Geballe, M. T. SiteHopper - a unique tool for binding site comparison. J. Cheminf. 2014, 6, 57. (52) Genheden, S.; Ryde, U. The mm/pbsa and mm/gbsa methods to estimate ligand-binding affinities. Expert Opin. Drug Discovery 2015, 10, 449−461. (53) Rabiller, M.; Getlik, M.; Klüter, S.; Richters, A.; Tuckmantel, S.; Simard, J. R.; Rauh, D. Proteus in the world of proteins: 8815

DOI: 10.1021/acs.jmedchem.7b00841 J. Med. Chem. 2017, 60, 8801−8815