结肠癌中骨形成蛋白-6启动子异常甲基化

Hypermethylation of BMP-6 in human colorectal carcinoma

目的研究骨形成蛋白-6(BMP-6)启动子在结肠癌细胞中的甲基化状态。方法运用甲基化特异PCR(MSP)法检测30例原发结肠癌和癌旁组织中BMP-6的甲基化水平。甲基化修饰后亚硫酸盐测序PCR(BSP)分析结肠癌细胞COLO-205细胞BMP-6启动子CpG岛甲基化状态。提取细胞RNA,通过实时定量PCR(real time-PCR)检测BMP-6 mRNA在不同浓度的DNA甲基化酶抑制剂5’-杂氮-2’-脱氧胞嘧啶(5-aza-dC)处理COLO-205细胞后BMP-6 mRNA的改变情况。结果原发性结肠癌的甲基化异常检出率是33.3%(10/30)。BMP-6在COLO-205细胞中存在高甲基化状态,COLO-205细胞经5-aza-dC处理后BMP-6 mRNA表达明显上调。结论BMP-6在原发性结肠癌中存在甲基化异常,说明BMP-6基因甲基化异常可能参与结肠癌的发生。

Objective To detect the methylation status of BMP-6 promoter in colorectal carcinoma （CRC）cells. Methods Thirty primary CRC tissues and corresponding normal tissues were detected by Methylationspecific PCR （MSP） method. Methylation status of BMP-6 promoter in CRC cell line COLO-205 was detected by Bisulfite-sequencing PCR （BSP）. And the expression of BMP-6 in COLO-205 or cells treated with increasing mount of demethylation agent, 5- aza-dC was identified by RT-PCR. Results Aberrant methylation in primary CRC was 33.3% （10/30）. Hypermethylation of BMP-6 was observed in COLO-205 cells. Increased BMP-6 mRNA can be restored in COLO-205 after treatment with 5-aza-dC. Conclusion The promoter hypermethylation of BMP-6 may play an important role in tumorigenesis of CRC.