抑制HIF1α表达对低氧培养SGC-7901胃癌细胞CD44表达的影响

Effect of HIF1α Down-regulation on CD44 Expression in Gastric Cancer Cell Line SGC7901 in Hypoxia

目的研究低氧条件下胃癌细胞HIF1α及CD44的表达变化,并观察下调HIF1α表达对CD44表达的影响。方法以人胃癌细胞系SGC7901细胞为研究对象,分别于正常氧压及含1%O2条件下传代培养1周。随后加入20 nm/L雷帕霉素培养72 h,CCK8法检测细胞活力,Transwell试验检测细胞侵袭能力,实时定量PCR及western blot检测CD44及HIF1α的m RNA及蛋白表达。结果与正常组对比,低氧条件下细胞增殖活性明显升高(P<0.05),侵袭活性明显增强(P<0.05),HIF1α及CD44基因的m RNA及蛋白表达水平明显升高(P<0.01)。雷帕霉素处理后,不论在常氧及低氧条件下细胞活力均较对照组弱(P<0.05),细胞侵袭活性明显下降(P<0.05)。细胞HIF1α和CD44的m RNA及蛋白表达水平均明显降低(P<0.01)。结论低氧条件下胃癌细胞SGC7901增殖及侵袭能力明显增强,下调细胞的HIF1α表达后,显著降低CD44的表达。由此可推测,低氧可能通过HIF1α调节CD44的表达,调控胃癌细胞增殖及侵袭潜能。

Objective To observe the change of expression of HIF1α and CD44 in human gastric cell line SGC7901 in hypoxia,and the effect of down-regulating HIF1α expression on CD44 expression. Methods SGC7901 cells were cultured in 1%O2condition for 1 week,and then treated with 20 nm / L rapamycin for 72 h. Cell viability was measured by CCK8 assay. Cell invasion was detected by Transwell invasion assay. Protein and m RNA expression of HIF1α and CD44 was detected by Western blotting and real-time RT-PCR. Results Compared with the control group,cell viability and invasion obviously increased in hypoxia( P < 0. 05),but decreased after treated with rapamycin( P < 0. 05). Protein and m RNA expression of HIF1α and CD44 obviously decreased in hypoxia( P < 0. 05),and inhibited by rapamycin( P < 0. 05). Conclusion In hypoxia,the proliferation and invasion of SGC7901 increased,and down-regulating the expression of HIF1α can significantly inhibit CD44 expression. Therefore,it is possible that hypoxia can regulate the CD44 expression of gastric cancer cell via HIF1α,and regulate cell proliferation and invasion.