胃癌细胞株MGC803中LTF基因的表达及其启动子甲基化相关性研究

摘要

Objective To investigate the expression of LTF (lactotransferrin) gene and its promoter region in human gastric cancer cel line MGC803. Methods The expression of LTF mRNA and protein levels in MGC803 cel s were detected by real- time PCR and Western blot, respectively;LTF promotor methylation status was determined by Bisulfite genomic sequencing PCR (BSP). MGC803 cel s were treated with 5- aza- CdR to reverse methylation status, Results LTF promotor methylation rate in MGC803 was 59.8%. Compared to control group, methylation status and mRNA expression of LTF in 5- aza- CdR treatment groups(2μmol/L and 10μmol/L) were reversed(P<0.05);however there was no difference between different treatment groups(P>0.05). Conclusion The LTF methylation in promoter region is high and LTFmRNA expression in MGC803 cel s is low, 5- aza- CdR can reverse the methylation status and up- regulate LTF mRNA expression.%目的：检测胃癌细胞株MGC803内乳铁蛋白（LTF）基因的甲基化和表达情况，探讨LTF的DNA启动子区甲基化异常与其在胃癌内表达的相关性。方法用亚硫酸氢盐测序PCR方法检测MGC803启动子区甲基化状态，使用real- time PCR和Western blot分别检测LTF在MGC803内的mRNA和蛋白表达水平。同时使用去甲基化剂5- aza- CdR处理胃癌细胞株，观察给药前后的DNA甲基化状态和mRNA表达情况。结果 MGC803启动子甲基化率达59.8%，使用5- aza- CdR处理的两组（2μmol/L组和10μmol/L组）和空白对照组甲基化率差异、LTF的mRNA表达差异均有统计学意义（均P＜0.05），并且随着MGC803启动子甲基化程度的下降，其mRNA和蛋白表达增加；而不同浓度药物处理组间差异均无统计学意义（均P＞0.05）。结论 LTF基因在胃癌细胞株MGC803内表现为较高甲基化状态，而且LTF的表达和其启动子区甲基化情况相关，使用去甲基化剂能逆转DNA的甲基化情况从而使其mRNA重新表达。