JAM3基因甲基化是食管鳞状细胞癌潜在的分子标志物

目的研究JAM3基因启动子区在食管癌中的甲基化情况及其表达调控机制,探讨JAM3基因启动子区异常甲基化作为食管鳞状细胞癌的潜在诊断标志物和治疗靶标。方法应用半定量RT-PCR、甲基化特异性PCR等技术对7个食管癌细胞系(KYSE140、KYSE150、KYSE410、KYSE450、COLO680N、KYSE520和TE13)、5例正常食管黏膜组织和83例原发性食管鳞状细胞癌组织进行分析。结果JAM3 mRNA在KYSE520、KYSE140、KYSE450细胞中高表达,这些细胞的JAM3基因启动子区呈非甲基化状态。JAM3 mRNA在KYSE410、COLO680N、TE13、KYSE150细胞中表达缺失,且其基因启动子区在这些细胞中呈完全甲基化。经过5-Aza-dc处理后,JAM3基因在KYSE410、COLO680N、TE13、KYSE150细胞中恢复表达。这些结果表明,JAM3在食管癌细胞中的表达受启动子区甲基化的调控。JAM3基因启动子区在5例正常食管黏膜组织中呈非甲基化状态(0/5),而在原发性食管鳞状细胞癌中其甲基化率为50.6%(42/83),且JAM3甲基化与肿瘤的位置相关(P<0.05)。结论JAM3在食管鳞状细胞癌中频繁发生甲基化,JAM3基因的表达受启动子区甲基化的调控,JAM3基因是潜在的食管癌诊断标志物和治疗靶标。

Promoter region methylation of JAM3 is a potential diagnostic marker and therapeutic target in human esophageal squamous cell carcinoma

Objective To explore the promoter region methylation status of JAM3 gene and the mechanism of JAM3 expression regulation in human esophageal cancer.Methods Seven esophageal cancer cell lines(KYSE140, KYSE150, KYSE410, KYSE450, COLO680 N,KYSE520 and TE13), 5 cases of normal human esophageal mucosa and 83 cases of primary human esophageal squamous cell carcinoma were employed. Semi-quantitative RT-PCR and methylation specific PCR(MSP) techniques were used to detect the expression and methylation status of JAM3.Results JAM3 mRNA was highly expressed in KYSE520, KYSE140 and KYSE450 cells, and the promoter region was unmethylated in these cells. While, the expression of JAM3 was lost in KYSE410, COLO680 N, TE13 and KYSE150 cells, and the promoter region was completely methylated in these four cells. The expression of JAM3 was induced by 5-Aza-2′-deoxycytidine treatment. These results suggested that the expression of JAM3 was regulated by promoter region methylation in esophageal cancer. Methylation of JAM3 was found in 50.6%(42/83) of primary esophageal squamous cell carcinoma samples, while no methylation was examined in normal esophageal mucosa(0/5). Methylation of JAM3 was significantly associated with tumor location(P<0.05).Conclusion JAM3 is frequently methylated in human esophageal squamous cell carcinoma, and the expression of JAM3 is regulated by promoter region methylation. Methylation of JAM3 is a potential diagnostic marker and therapeutic target in human esophageal cancer.