Stathmin Regulates Hypoxia-Inducible Factor-1α Expression through the Mammalian Target of Rapamycin Pathway in Ovarian Clear Cell Adenocarcinoma.

ABSTRACT: Stathmin, a microtubule-destabilizing phosphoprotein, is highly expressed in ovarian cancer, but the pathophysiological significance of this protein in ovarian carcinoma cells remains poorly understood. This study reports the involvement of stathmin in the mTOR/HIF-1 α /VEGF pathway in ovarian clear cell adenocarcinoma (CCA) during hypoxia. HIF-1 α protein and VEGF mRNA levels were markedly elevated in RMG-1 cells, a CCA cell line, cultured under hypoxic conditions. Rapamycin, an inhibitor of mTOR complex 1, reduced the level of HIF-1 α and blocked phosphorylation of ribosomal protein S6 kinase 1 (S6K), a transcriptional regulator of mTOR, demonstrating that hypoxia activates mTOR/S6K/HIF-1 α signaling in CCA. Furthermore, stathmin knockdown inhibited hypoxia-induced HIF-1 α and VEGF expre

SUBMITTER: Tamura K 

PROVIDER: S-EPMC3683482 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature