摘要
目的:通过观察低氧对SGC7901细胞株SP细胞的影响及其与HIF-2α和ABCG2表达变化的关系,初步探讨低氧对肿瘤干细胞的影响及机制。方法:用氯化钴(CoCl2)创建低氧模型。Hoechst33342染色法检测SP细胞比例,免疫荧光细胞化学法检测ABCG2在SP和非SP细胞中的表达,免疫细胞化学法检测HIF-2α和ABCG2蛋白的表达,RT-PCR法检测ABCG2mRNA的表达。结果:SP细胞比例为2.36%,低氧诱导后其比例逐渐增加,P<0.05。ABCG2在SP细胞中的表达明显高于非SP细胞(P<0.01),低氧诱导后在SP细胞和非SP细胞中的表达均增强(P值均<0.01),且在SP细胞中的表达高于非SP细胞,P<0.01。低氧诱导后HIF-2α、ABCG2蛋白及ABCG2mRNA的表达较常氧组明显增强(P值均<0.01),且HIF-2α与ABCG2蛋白表达呈高度正相关(n=4,r=0.893,P<0.05)。结论:低氧能促进SGC7901细胞株SP细胞比例的增加,其机制可能与低氧激活HIF-2-αABCG2通路的表达,促进肿瘤细胞的干细胞化及维持干细胞的未分化状态有关。
OBJECTIVE： To observe the effect of hypoxia on the ratio of side population （SP） cells in human gastric cancer cell line SGC7901 and its relationship with the expression of hypoxia inducible factor-2 alpha （HIF-2α and ABCG2, initially investigate the effects of hypoxia on cancer stem cells and its mechanism. METHODS： The model of hypoxia was established by COC12. The percentage of SP cells in human gastric cancer cell line SGC7901 was detected by Hoechst 33342 staining, and the expression of ABCG2 proteins in SP cells and non-SP was detected by fluorescence immunocytochemical method. The expression of HIF-2α and ABCG2 proteins was detected by immunocytochemical staining. The expression of ABCG2 mRNA was detected by RT-PCR. RESULTS： The ratio of SP cells in SGC7901 cells was 2. 36% under normoxia. While after induced by hypoxia, there was a statistically significant increase compared with the normoxia （P〈0.05）. The expression of ABC2 protein in SP cells was evidently higher than that in non-SP cells under normoxia（P〈0.01）. While after induced by hypoxia, its expression significantly increase in a time-dependent manner both in SP and non-SP cells （both P〈0. 01）, and the expression in SP cells was more higher than in non-SP cells（P〈0.01）. The expression of HIF-2α and ABCG2 protein and ABCG2 mRNA under hypoxia was evidently higher than the normoxia （all P〈0. 01）. A significant positive correlation was noted between the expression of HIF-2α and ABCG2 protein in SCK;7901 cells （n= 4, r= 0. 893, P〈0. 05）. CONCLUSIONS： Hypoxia can increase the ratio of SP cells in human gastric cancer cell line SGC7901. It may be related to the activation of HIF-2α ABCG2 pathway by hypoxia, which increase cancer cell stemness by promoting cancer cells dedifferentiation and maintainning cancer stem cells undiferentiated state.
出处
《中华肿瘤防治杂志》
CAS
2011年第12期921-925,共5页
Chinese Journal of Cancer Prevention and Treatment
基金
山东省中医管理局中医药科技发展计划基金资助项目(2007-156)
关键词
胃肿瘤
SP细胞
低氧诱导因子-2α
ABCG2
stomach neoplasms
side population cell
hypoxia inducible factor 2 alpha
ABCG2
