叶酸对胃癌细胞生物学特征以及alkB基因表达的影响

背景:抑癌基因启动子区DNA超甲基化是胃癌发生的重要机制之一。alkB基因可修复甲基化损伤,而叶酸对胃癌的发生起有预防作用;但叶酸的作用是否与alkB基因表达相关尚不清楚。目的:探讨叶酸对胃癌细胞生物学特征以及alkB基因表达的影响。方法:培养人胃癌细胞株SGC7901,分别以0mg/L、0.2mg/L、0.4mg/L、0.8mg/L、1.0mg/L和2.0mg/L浓度叶酸进行干预。以CCK-8法检测细胞增殖活力,流式细胞术分析细胞周期,实时定量RT-PCR法检测alkB基因mRNA表达。结果:与空白对照组相比,0.2mg/L、0.4mg/L浓度叶酸能明显抑制胃癌细胞增殖活力,G0/G1期细胞百分比显著减少;alkB基因mRNA表达明显上调。结论:叶酸干预可抑制胃癌细胞增殖,同时上调alkB基因表达,推测alkB基因表达改变或许参与叶酸抑制胃癌细胞增殖的作用机制。

Effect of Folic Acid on Biological Characteristics of Gastric Cancer Cell and Expression of alkB Gene

Background： Hypermethylation of promoter region of tumor suppressor gene is an important mechanism of gastric carcinogenesis, alkB gene can repair methylation damage, and folie acid plays a role in prevention of gastric cancer. However, it is not clear whether there is a relationship between effect of folic acid and alkB gene expression. Aims： To investigate the effect of folic acid on biological characteristics of gastric cancer cell and expression of alkB gene. Methods： Human gastric cancer cell line SGC7901 was cultured, and folie acid concentration at 0 mg/L, 0.2 mg/L, 0.4 mg/L, 0.8mg/L, 1.0 mg/L and 2.0 mg/L were added, respectively, for intervention of SGC7901 cell growth. CCK-8 method was used to assess cell proliferation and viability, flow cytometry was used to determine cell cycle, and mRNA expression of alkB gene was measured by real-time quantitative RT-PCR. Results： Compared with blank control cells, the proliferation and viability of gastric cancer cell was significantly inhibited by 0.2 mg/L and 0.4 mg/L folic acid, the percentage of G0/G1 phase ceils was significantly decreased, and the mRNA expression of alkB gene was significantly up- regulated. Conclusions： Intervention with folic acid can inhibit the proliferation of gastric cancer cell and up-regulate the expression of alkB gene. Therefore we propose that changes of alkB gene expression may be involved in folic acid suppression mechanism on proliferation of gastric cancer cell.