Hypoxia induces STC1 expression. (A) The mRNA expression trend of STC1 and hypoxia inducible factor-1-alpha (HIF-1α) in ccRCC cell lines and HKC cells. (B) The association between STC1 and HIF-1α mRNA expression in clinical samples. (C) Representative images showed the morphological changes of RCC cell lines and HKC cells after CoCl2 treatment (magnification, ×100). (D) The mRNA level changes of STC1 and HIF-1α in A498 and Caki-2 cells after CoCl2 treatment. *,P < 0.05; **,P < 0.01; ***,P < 0.001.