Objective: To investigate effects of stanniocalcin-1 （STC-1） on proliferation balance under hypoxic condition in renal cancer cells and its mechanism. Methods: Hypoxic model was induced on renal cancer GRC-1 cells （Group H）, the cells were treated with STC-1 protein at concentrations of 0.1 nmol/L （H1, 0.5 nmol/L （H2）, 1.0 nmol/L （H3）, or normal saline （H0） for 48 h, respectively. Cells proliferation was measured by MTT assay; mRNA and protein expressions of hypoxia inducible factor 1α （HIF-1α） and STC-1 in GRC-1 cells were detected by RT-PCR and ELISA, respectively; the intracellular levels of Ca²⁺ and adenosine triphosphate （ATP） were determined by fluorescence spectrophotometry and spectrophotometry， respectively. Results:

The expression of HIF-1α, STC-1 and Ca²⁺ levels were increased in GRC-1 cells under hypoxia condition; STC-1 reversed these changes in a dose-effect manner. Hypoxia significantly inhibited cell proliferation and the generation of ATP in GRC-1 cells and exogenous STC-1 reversed the effects of hypoxia; ATP generation increased gradually with increasing STC-1 concentration, but the cell proliferation was reduced. Conclusion: Exogenous STC-1 can promote the proliferation of renal cancer cells in hypoxia condition by reducing HIF-1α expression and Ca²⁺ content and increased ATP production, but the progressive inhibition of HIF-1 α hindered the renal carcinoma cell proliferation further, which indicates that STC-1 may be involved in anti-hypoxia proliferative balance of renal cancer cells．