potentiate the cidal effect of this nitroimidazole.

no evidence for increased sub G1 cell populations or pronounced XL765 induced apoptotic cell death was observed. Cell lines utilized were re fingerprinted, Crizotinib as per above, during their use for the current study. Compounds utilized in our studies included the small molecule dual PI3K/mTOR inhibitor, XL765, the dual PI3K/mTOR inhibitor, PI103, and the mTORC1 inhibitor rapamycin. XL765 chemical structure will be described in a manuscript currently in preparation by Sanofi, structure of other compounds is provided in Fig 1A. Further information can be found in Supplementary data. Cellular growth and autophagy related assays Experiments were conducted in multiple cell lines and with either or/both inhibitors as previously described. Assessing autophagy mandates the conduct of multiple complementary assays evaluating both autophagosome accumulation as well as autophagic flux. Studies conducted here followed recently published guidelines and were performed as previously described. Immune system Transfection procedures were performed as previously described. Additional information can be found in supplementary data. In vivo xenograft therapeutic experiments All animal procedures and care were approved by the MD Anderson Cancer Center Institutional Animal Care and Usage Committee. Animals received humane care as per the Animal Welfare Act and the NIH Guide for the Care and Use of Laboratory Animals. Animal experiments were conducted as previously described. Detailed information regarding animal models, therapeutic regimens, schedule and doses can be found in Supplemental Data. The dual PI3K/mTOR inhibitor XL765 inhibits MPNST cell growth We have previously demonstrated that PI3K/mTOR blockade exerts marked anti MPNST effects in vitro utilizing the experimental inhibitor PI103. Seeking to expand these initial studies and evaluate the impact of this therapeutic strategy on MPNST local and metastatic growth in vivo, we opted Oprozomib to test the effect of a novel PI3K/mTOR inhibitor, XL765, currently in human clinical trials. First, we confirmed the anti MPNST effects of this compound on cultured human MPNST cells. Dose range selected was in accordance with previously published pre clinical studies and per companys recommendation. XL765 was found to induce a marked dose dependent decrease in the phosphorylation of AKT and the mTOR downstream targets 4EBP1 and S6K. MPNST cell treatment with increasing XL765 doses induced significant growth inhibition, extrapolated XL765 IC50 concentrations were found to be S462 0. 81uM, MPNST724 0. 86uM, STS26T 1. 75uM, MPNST642 1. 93uM, and ST88 2. 49uM. Similarly, a XL765 dose dependent decrease in MPNST cell colony forming capacity was noted. Concurring with our previous PI103 studies, XL765 treatment resulted in G1 cell cycle arrest in MPNST cells.