候选抑癌基因Syk启动子甲基化与胃癌转移相关

目的：探讨Syk（spleen tyrosine kinase）基因启动子甲基化在胃癌发生、转移过程中的作用及其临床意义。方法：采用RT-PCR检测61例胃癌组织、癌旁组织中SykmRNA的表达．并用甲基化特异性PCR（MSP）方法检测Syk基因启动子甲基化情况。结果：61例癌旁组织均检测到Syk基因的表达，胃癌组织有14例检测到Syk基因的表达，Syk基因在胃癌组织中表达率显著降低（P〈0．05）。61例胃癌旁组织未发现有Syk基因启动于的甲基化。而61例癌组织中有21例检测到Syk基因启动子的甲基化。癌组织Syk基因启动于甲基化率显著高于癌旁组织（P〈0．05）。有淋巴结转移的31例胃癌组织中，有17例Syk基因启动子甲基化，有淋巴结转移的Syk基因启动于甲基化姓著高于无淋巴结转移组（P〈0．05）。结论：Syk基因启动于甲基化是导致Syk基因失活的原因之一。Syk基因启动子的甲基化可能与胃癌的发生、转移有关。

Relationship between hypermethylation of Syk gene in promoter and oncogenesis,metastasis of gastric carcinoma

Objective: To study the correlation between methylation of Syk (spleen tyrosine kinase)gene in promoter region with oncogenesis, metastasis of gastric carcinoma. Methods:Using RT-PCR technique, specimens from 61 patients with gastric cancer (tumor tissues, adjacent normal tissues) were detected to analyse Syk expression . Meanwhile, Methylation-specific PCR was used to detect methylation of Syk promoter region. Results: Syk gene was expressed in all normal gastric tissues, while in 61 cases of gastric carcinoma samples, only 14 showed the expression of Syk mRNA.Syk expression in gastric carcinoma was lower than that in adjacent normal tissues(P < 0.05). No methylation of Syk promoter was found in adjacent normal tissues, while 21 out of 61 cases of gastric carcinoma (42.5%) were detected hypermethylation of Syk gene in promoter region.The rate of methylation of Syk promoter in gastric carcinoma was higher than that in adjacent normal tissues(P < 0.05). In 31 cases with lymph node metastasis, 17 were found with Syk promoter methylation. A significant difference was noted between two groups(P < 0.05). Conclusion:Hypermethylation leads to inactivation of the Syk gene in human gastric carcinoma. Methylation of Syk promoter might be related with oncogenesis, metastasis of gastric carcinoma.