摘要
目的探讨长散在重复序列(long interspersed nucleotide element-1,LINE-1)启动子区DNA甲基化水平与食管癌发生的关系。方法采用甲基化特异性上述聚合酶链式反应(polymerase chain reaction,PCR)和焦磷酸测序法检测96例食管癌组织、癌旁组织和远癌组织标本中LINE-1基因甲基化水平,并用统计学方法分析LINE-1甲基化与食管癌临床特征及吸烟等生活习惯的关系。结果 96例癌组织、癌旁组织和远癌组织中LINE-1甲基化水平差异均无统计学意义(均有P>0.05)。LINE-1启动子区甲基化与食管癌患者的年龄、饮酒、家族史、病理组织类型、肿瘤部位及临床病理分期之间差异均无统计学意义(均有P>0.05);与患者性别、吸烟和分化程度之间差异均有统计学意义(均有P<0.05)。结论 LINE-1启动子区甲基化在食管癌患者中较为普遍,LINE-1启动子区低甲基化常发生于食管癌低分化组织和TNM晚期,LINE-1基因甲基化有潜力在食管癌诊断和预后监测方面发挥重要作用。
Objective To study the function of long interspersed nucleotide element-1(LINE-1) promoter region methylation in the development of esophageal cancer. Methods Pyrosequencing was applied to detect methylation levels of the promoter region of LINE-1 in 96 cases of esophageal cancer tissuses, pericancerous tissue and tissues distant from esophageal cancer. Statistical methods were performed to correlate the level of LINE-1 methylation with clinical features and living habits of the patients. Results The methylation level of LINE-1 was not significantly different among the esophageal cancer tissuses, pericancerous tissue and tissues distant from esophageal cancer(all P>0.05). Among 96 cancer tissuses, no association was found between methylation status of LINE-1 promoter region and age, drinking, family history, histopathological types, tumor locaton and tumor stage(all P>0.05). Metylation status of LINE-1 promoter region was associated with gender, smoking history and tumor differentiation(all P<0.05). Conclusion The methylation of LINE-1 is frequently happened to esophageal cancer. Promoter region hypermethylation of LINE-1 is often occurred to poor differentiated esophageal cancer and advanced TNM stage. The methylation of LINE-1 may play an important role in the diagnosis and prognosis monitoring of esophageal cancer.
引文
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