The reactions were conducted in 50 ml volumes in 96-well plates and contained GST-tagged human-recombinant ABL1(T315I) kinase intracellular domain (1 nM), 3 mM phosphoacceptor peptide, 59 FAM-
EAIYAAPFAKKK-OH (CPC Scientific, also known as ProfilerPro Peptide 2, Caliper Life Sciences), test compound (11-dose threefold serial dilutions, 2% DMSO final) or DMSO only, 1 mM dithiothreitol (DTT), 0.002% Tween-20 and 5 mM MgCl2 in 25 mM HEPES, pH 7.1
Abstract
The BCR-ABL1 fusion gene is a driver oncogene in chronic myeloid leukaemia and 30–50% of cases of adult acute lymphoblastic leukaemia1. Introduction of ABL1 kinase inhibitors (for example, imatinib) has markedly improved patient survival2, but acquired drug resistance remains a challenge3,4,5. Point mutations in the ABL1 kinase domain weaken inhibitor binding6 and represent the most common clinical resistance mechanism. The BCR–ABL1 kinase domain gatekeeper mutation Thr315Ile (T315I) confers resistance to all approved ABL1 inhibitors except ponatinib7,8, which has toxicity limitations. Here we combine comprehensive drug sensitivity and resistance profiling of patient cells ex vivo with structural analysis to establish the VEGFR tyrosine kinase inhibitor axitinib as a selective and effective inhibitor for T315I-mutant BCR–ABL1-driven leukaemia. Axitinib potently inhibited BCR–ABL1(T315I), at both biochemical and cellular levels, by binding to the active form of ABL1(T315I) in a mutation-selective binding mode. These findings suggest that the T315I mutation shifts the conformational equilibrium of the kinase in favour of an active (DFG-in) A-loop conformation, which has more optimal binding interactions with axitinib. Treatment of a T315I chronic myeloid leukaemia patient with axitinib resulted in a rapid reduction of T315I-positive cells from bone marrow. Taken together, our findings demonstrate an unexpected opportunity to repurpose axitinib, an anti-angiogenic drug approved for renal cancer, as an inhibitor for ABL1 gatekeeper mutant drug-resistant leukaemia patients. This study shows that wild-type proteins do not always sample the conformations available to disease-relevant mutant proteins and that comprehensive drug testing of patient-derived cells can identify unpredictable, clinically significant drug-repositioning opportunities.
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Boehm, M., Beaumont, K., Jones, R.M., Kalgutkar, A.S., Zhang, L., Atkinson, K., Bai, G., Brown, J.A., Eng, H., Goetz, G.H. and Holder, B.R. Journal of Medicinal Chemistry (2017).
- Pfizer Worldwide Research & Development, Cambridge, Massachusetts 02139, United States
- Pfizer Worldwide Research & Development, Groton, Connecticut 06340, United States
The chemokine receptor CXCR7 is an attractive target for a variety of diseases. While several small-molecule modulators of CXCR7 have been reported, peptidic macrocycles may provide advantages in terms of potency, selectivity, and reduced off-target activity
Bainbridge, Travis W., et al. Scientific Reports 7.1 (2017): 12524.
- Protein Chemistry, Molecular Oncology, Discovery Chemistry, Cancer Immunology, and Neuroscience. Genentech Inc., South San Francisco, CA, 94080, USA
"ANP FAP and aP NIRF were synthesized by CPC Scientific (Sunnyvale, CA)… Another internally-quenched FRET peptide substrate (ANPFAP) for FAP has recently been reported and demonstrated for use as an activity-based, in vivo imaging tool. The peptide sequence contains two internal Gly-Pro dipeptide motifs, susceptible to FAP cleavage and a Cy5.5/QSY21, quenched-FRET pair."
Coorens, Maarten, et al. The Journal of Immunology 199.4 (2017): 1418-1428.
"CATH-2 and LL-37 were synthesized by Fmoc-chemistry at CPC Scientific (Sunnyvale, CA)."
Tcholakov, I., Grimshaw, C.E., Shi, L., Kiryanov, A., Murphy, S.T., Larson, C.J., Plonowski, A. and Ermolieff, J. Bioscience Reports 37, no. 3 (2017): BSR20170275.
- Departments of In Vitro Pharmacology, Immunology, Enzymology and Biophysical Chemistry, Medicinal Chemistry, External Innovation, Metabolic Disease, In Vitro Pharmacology, and Gastrointestinal and Enterology Discovery Unit, Takeda California, Inc., 10410 Science Center Drive, San Diego, CA 92121, U.S.A
The substrate used for our PHD2 kinetic study was a 17-mer peptide mimicking the sequence of HIF-1a surrounding the Pro564 residue hydroxylated by the PHD enzymes (Biotin-DLEMLAPYIPMDDDFQL). The substrate used for FIH1 was a 34-mer peptide mimicking the sequence of HIF-1α surrounding residue Asn803 (DESGLPQLTSYDCEVNAPIQGSRNLLQGEELLRAL). Both peptides were synthesized by CPC Scientific Inc.
Wilson, Sarah S., et al. PLoS Pathogens 13.6 (2017): e1006446.
"Cryptdin 2 (UniProtKB: P28309, LRDLVCYCRTRGCKRRERMNGTCRKGHLMYTLCCR)... obtained by oxidative refolding of partially purified linear peptides (synthesized by CPC Scientific...) and purifying the correctly folded species by reverse-phase high-pressure liquid chromatography (RP-HPLC). Purity was determined by analytical RP-HPLC, and the mass of the disulfide-bonded peptides was verified by high mass accuracy liquid chromatography-mass spectrometry."
Sattiraju, A., et al. Oncotarget 2017, 8 (26), 42997-43007.
For Ac-225 labeling, the prepared DOTA-Pep-1L (CPC-scientific, San Jose, CA) was incubated with Ac-225 at 70°C for 50 minutes. The TLC plates were scanned on a BioScan Imaging Scanner. Cu-64 was purchased from Washington University in St. Louis. The custom peptide specific to IL13RA2 and a scrambled peptide were conjugated with NOTA by CPC scientific Inc (San Jose, CA). Both the peptides, Pep-1L and scrambled peptide-NOTA were radiolabeled with Cu-64 according to the previously reported methods [15].
Puthenveetil, Sujiet, et al. PloS One 12.5 (2017): e0178452.
- Worldwide Medicinal Chemistry, Pfizer Global R&D, Groton, Connecticut, United States of America.
- Pfizer Oncology Research, Pearl River, NY, United States of America.
"Peptide-payload conjugate (7) was prepared by reacting 2mM aizoacetyl-Ser-Lys-Gly-Ser-Lys (CPC scientific, inc. Sunnywale, CA) with 8 mM NHS-ester payload [19] in 50% Dimethyl sulfoxide (DMSO), 50 mM borate buffer pH 8.5 for 2 h at 37°C."
Kwon, Ester J., et al. Advanced Materials 29.35 (2017).
"[..] synthesized for initial screening with FAM-conjugated lysine at the C-terminal end of the membrane-interactive peptide and with or without D[KLAKLAK]2 on the C-terminus using standard Fmoc chemistry[..] All peptides were synthesized with N-terminal myristic acid and C-terminal amine. [..] larger quantities of the peptides were synthesized by CPC Scientific to 90% purity"
Noland, Cameron L., et al. Proceedings of the National Academy of Sciences 114.30 (2017): E6044-E6053.
- Departments of Structural Biology, Infectious Diseases, Biochemical and Cellular Pharmacology, Pathology, Translational Immunology, and Biomolecular Resource Group, Genentech, Inc., South San Francisco, CA 94080.
"..peptide substrates were synthesized based on the Pal lipoprotein, Pal peptideshort (Pam2Cys-SSNKNGGK-Biotin; CPC Scientific, Inc.).."