亚硒酸钠抑制人胃癌SGC-7901细胞系增殖和hTERT的表达

Effects of sodium selenite on the growth and hTERT expression of gastric cancer SGC-7901 cell line

目的探讨亚硒酸钠对人胃癌SGC-7901细胞系增殖和hTERT表达的作用及其机制。方法用含亚硒酸钠(0μmol/L、0.5μmol/L、2.5μmol/L、5μmol/L、8μmol/L)的培养液培养SGC-7901细胞24h、48h、72h、96h,通过四甲基偶氮唑盐(MTT)比色法检测亚硒酸钠对SGC-7901的增殖的影响,免疫细胞化学SABC法和RT-PCR检测亚硒酸钠对人胃癌细胞系SGC-7901hTERT蛋白和hTERTmRNA表达的作用。结果亚硒酸钠对人胃癌SGC-7901细胞具有明显的抑制作用,且随亚硒酸钠浓度的增加和培养时间的延长对SGC-7901细胞生长抑制作用逐渐加强。SGC-7901细胞hTERT蛋白免疫细胞化学染色的平均吸光度(AA),随0.5μmol/L、2.5μmol/L亚硒酸钠组培养时间增加逐渐降低,96h时明显低于空白对照组(P<0.01),5μmol/L、8μmol/L亚硒酸钠组的AA每个时间点均比空白对照组明显降低(P<0.01)。0.5μmol/L亚硒酸钠组SGC-7901 hTERTmRNA的表达无明显的变化;在2.5μmol/L亚硒酸钠组则随时间增加逐渐降低,48h后明显低于空白对照组;5μmol/L、8μmol/L亚硒酸钠组均明显低于空白对照组(P<0.01),72h后明显低于其他低硒组。结论亚硒酸钠抑制人胃癌SGC-7901细胞生长,下调hTERT表达。

Objective To investigate effects of sodium selenite on human gastric cancer SGC-7901 cell growth and hTERT expression and to explore the mechanism. Methods SGC-7901 cells were treated with different concentrations （0μmol/L,0. 5 μmol/L,2. 5μmol/L, 5 μmol/L, 8μmol/L） of sodium selenite for 24 hours, 48 hours, 72 hours and 96 hours. Growth inhibition of SGC-7901 cells was detected by assay of MTT. Immunohistochemical SABC method and RT- PCR assay were used to study the changes of hTERT proteins and hTERT mRNA in SGC-7901 ceils. Results Sodium selenite significantly suppressed the growth of SGC-7901 cells. The cell growth rate reduced in a dose-and time-dependent manner. The same changes had occurred for the hTERT protein level in SGC-7901 cells. The averae absorbance （AA） of hTERT protein in SGC-7901 cells was gradually lower along time, unto 96 hour it was significantly decreased in 0. 5μmol/L sodium selenite group or 2. 5μmol/L sodium selenite group than that in blank control group （ P 〈 0.01 ）. It was significantly decreased in 5μmol/L, 8μmol/L sodium selenite group than in blank control group all time （P 〈 0.01 ）. RT- PCR results demonstrated there was no obvious alteration of hTERT mRNA levels after 0. 51xmoL/L sodium selenite treatment, hTERT mRNA levels were gradually reduced along time in 2. 5μmol/L sodium selenite group, there was significantly different after 48 hours treatment in 2. 5μmol/L sodium selenite group than in blank control group, hTERT mRNA levels were significantly decreased all time in 5μmol/L, 8μmol/L sodium selenite group than in blank control group （ P 〈 0.01 ） , unto 72 hours it, was significantly decreased than others lower sodium selenite groups （ P 〈 0.05 ）. Conclusion Sodium selenite suppressed the SGC-7901 cell growth, and down-regulated the hTERT expression.