Effect of HIF-1α on the proliferation of breast cancer MCF-7 cells and the mechanism

Objective To observe the effect of hypoxia-inducible factor-1α( HIF-1α) on the proliferation of breast cancer MCF-7 cells and to investigate the mechanism. Methods RNAi expression plasmids of HIF-1α were constructed and selected,and the breast cancer MCF-7 cells were transfected by the mediation of LipofectamineTM 2000. After 48 h,the transcription level of HIF-1α mRNA in transfected cells was detected by real-time RT-PCR to select HIF-1α RNAi plasmid with high interfering efficiency. CCK-8 kit was used to observe the changes in the proliferation of breast cancer cells before and after transfection,and real-time RT-PCR was used to detect the expression of Smathened protein(SMO) mRNA. Results pGPU6 / GFP / Neo / HIF-1α-shRNA1-4 plasmids were successfully constructed,the interference rate of HIF-1α shRNA-4 was 74% and had the highest interference efficiency(all P 0. 05). HIF-1α-shRNA-4 significantly inhibited the proliferation of MCF-7 cells after interference for 48 h,72 h and 96 h( all P 0. 05). The expression level of SMO mRNA decreased after HIF-1α shRNA-4 transfection in MCF-7 cells(0. 56 ± 0. 06 vs. 1. 07 ± 0. 16)( P 0. 05). Conclusion The expression of HIF-1α can promote the proliferation of breast cancer cells,which might be closely associated with the regulation of SMO expression.