Preclinical characterization of OSI-027, a potent and selective inhibitor of mTORC1 and mTORC2: distinct from rapamycin
Autor: | Shripad V. Bhagwat, Lee D. Arnold, Prafulla C. Gokhale, Andrew P. Crew, Lorina Dudkin, Yan Yao, Jennifer Kahler, Andy Cooke, Jennifer E. Workman, Robert A. Wild, Peter J. Houghton, David Epstein, Christine Mantis, Neil W. Gibson, Jonathan A. Pachter, Mark Bittner |
---|---|
Rok vydání: | 2011 |
Předmět: |
Cancer Research
Mice Nude P70-S6 Kinase 1 Apoptosis mTORC1 Biology Pharmacology Mechanistic Target of Rapamycin Complex 1 mTORC2 Mice Cell Line Tumor Animals Humans Phosphorylation Protein kinase B Protein Kinase Inhibitors PI3K/AKT/mTOR pathway Cell Proliferation Sirolimus Cell Death Cell growth Triazines TOR Serine-Threonine Kinases RPTOR Imidazoles PTEN Phosphohydrolase Proteins Xenograft Model Antitumor Assays Enzyme Activation Oncology Multiprotein Complexes Female Proto-Oncogene Proteins c-akt HeLa Cells Transcription Factors |
Zdroj: | Molecular cancer therapeutics. 10(8) |
ISSN: | 1538-8514 |
Popis: | The phosphoinositide 3-kinase (PI3K)/AKT/mTOR pathway is frequently activated in human cancers, and mTOR is a clinically validated target. mTOR forms two distinct multiprotein complexes, mTORC1 and mTORC2, which regulate cell growth, metabolism, proliferation, and survival. Rapamycin and its analogues partially inhibit mTOR through allosteric binding to mTORC1, but not mTORC2, and have shown clinical utility in certain cancers. Here, we report the preclinical characterization of OSI-027, a selective and potent dual inhibitor of mTORC1 and mTORC2 with biochemical IC50 values of 22 nmol/L and 65 nmol/L, respectively. OSI-027 shows more than 100-fold selectivity for mTOR relative to PI3Kα, PI3Kβ, PI3Kγ, and DNA-PK. OSI-027 inhibits phosphorylation of the mTORC1 substrates 4E-BP1 and S6K1 as well as the mTORC2 substrate AKT in diverse cancer models in vitro and in vivo. OSI-027 and OXA-01 (close analogue of OSI-027) potently inhibit proliferation of several rapamycin-sensitive and -insensitive nonengineered and engineered cancer cell lines and also, induce cell death in tumor cell lines with activated PI3K–AKT signaling. OSI-027 shows concentration-dependent pharmacodynamic effects on phosphorylation of 4E-BP1 and AKT in tumor tissue with resulting tumor growth inhibition. OSI-027 shows robust antitumor activity in several different human xenograft models representing various histologies. Furthermore, in COLO 205 and GEO colon cancer xenograft models, OSI-027 shows superior efficacy compared with rapamycin. Our results further support the important role of mTOR as a driver of tumor growth and establish OSI-027 as a potent anticancer agent. OSI-027 is currently in phase I clinical trials in cancer patients. Mol Cancer Ther; 10(8); 1394–406. ©2011 AACR. |
Databáze: | OpenAIRE |
Externí odkaz: |