Fas及TRF1、TRF2在亚硒酸钠诱导胃癌SGC-7901细胞凋亡过程中的表达

EXPRESSION OF FAS,TRF1 AND TRF2 IN THE APOPTOSIS OF SGC-7901 CELLS INDUCED BY SODIUM SELENITE

目的通过检测Fas蛋白及端粒结合蛋白TRF1、TRF2在亚硒酸钠诱导胃癌细胞SGC-7901细胞凋亡过程中的表达,探讨硒抗癌的机制。方法用含不同浓度亚硒酸钠(0.5、2.5、5.0、.8.0μmol/L)的培养液分别培养人胃癌细胞株SGC-7901细胞24、48、72、96h后,用流式细胞仪检测Fas蛋白的表达;链霉亲和素-生物素复合物(SABC)法和Western blot法检测TRF1、TRF2蛋白的表达。结果亚硒酸钠能提高Fas蛋白阳性表达细胞百分比(P<0.05)。免疫细胞化学法检测结果显示:亚硒酸钠可以降低TRF1蛋白和提高TRF2蛋白的灰度值(P<0.05)。Western blot检测结果显示:亚硒酸钠可以提高TRF1和降低TRF2蛋白表达强度(P<0.05)。它们都具有剂量依赖性。结论亚硒酸钠诱导胃癌SGC-7901细胞凋亡的机制可能跟上调Fas蛋白和TRF1蛋白表达,下调了TRF2蛋白表达有关。

Objective To study the mechanisms of selenium＇s anti-cancer by investigating the expressions of Fas and telomeric repeat binding factor 1,2 in human gastric cancer SGC-7901 cells apoptosis by sodium selenite, Methods SGC-7901 cells were treated with different concentrations （0.5, 2.5, 5.0, 8.0 μmol/L） of sodium selenite for 24, 48, 72, 96 hrs, The expression of Fas protein was detected by flow cytometry. The expression of TRF1, TRF2 protein was detected by method of immunocytochemical SABC （strept avidin-biotin complex） and Western blot. Results The results showed that sodium selenite increased the percentages of the Fas protein positive cells （P〈0.05）. Immunocytochemistry showed that sodium selenite reduced the grey value of TRF 1 protein and increased the grey value of TRF2 protein （P〈0.05）. Western blot showed that sodium selenite increased the TRF1 protein levels and reduced the TRF2 protein levels （P〈0.05）. All changes were concentration-dependent. Conclusion The mechanism underlying the effect of sodium selenite on SGC-7901 cell apoptosis is associated with increased TRF1 and Fas protein levels, and reduced TRF2 protein level.