MTORC1 drives HIF-1α and VEGF-A signalling via multiple mechanisms involving 4E-BP1, S6K1 and STAT3.

ABSTRACT: Recent clinical trials using rapalogues in tuberous sclerosis complex show regression in volume of typically vascularised tumours including angiomyolipomas and subependymal giant cell astrocytomas. By blocking mechanistic/mammalian target of rapamycin complex 1 (mTORC1) signalling, rapalogue efficacy is likely to occur, in part, through suppression of hypoxia-inducible factors (HIFs) and vascular endothelial growth factors (VEGFs). We show that rapamycin reduces HIF-1α protein levels, and to a lesser extent VEGF-A levels, in renal cystadenoma cells in a Tsc2+/- mouse model. We established that mTORC1 drives HIF-1α protein accumulation through enhanced transcription of HIF-1α mRNA, a process that is blocked by either inhibition or knockdown of signal transducer and activation of transcripti

SUBMITTER: Dodd KM 

PROVIDER: S-EPMC4172452 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature