Fig. 5.

Rac1, SOX2 and NEDD9 are required for hypoxia-induced HIF-1α expression. (a) MDA-MB-231 and MDA-MB-468 cells were incubated under hypoxia for the indicated periods. Cellular lysates were assayed for HIF-1α expression via western blotting. HIF-1α was quantified and normalized against β-actin. *p < 0.05, **p < 0.01. (b-d) After transfection with siSOX2 (b), siNEDD9 (c) or Rac1-T17 N plasmids (d), hypoxic cells were lysed and HIF-1α expression was determined using western blotting analysis. HIF-1α was quantified and normalized against β-actin. *p < 0.05, **p < 0.01