MGMT与hMLH1在胃癌组织中的表达及其临床相关性研究

目的：研究肿瘤修复基因蛋白产物MGMT、hMLH1在胃癌组织中的表达及其与胃癌临床病理特征的关系.方法：采用免疫组化方法（SP）检测96例胃癌切除标本中MGMT和hMLH1蛋白表达水平,并分析两者与胃癌临床病理特征的关系.结果：胃癌组织中MGMT和hMLH1在胃癌组织中的阳性率分别为74%（71/96）和65.6%（63/96）.MGMT and hMLH1的表达在胃癌组织学分类、浸润深度、淋巴结转移、肿瘤分期以及术后有无复发或远处转移等临床指标中具有统计学意义,P＜0.05;两者的表达在年龄、性别上的差异无统计学意义,P＞0.05.Kendall＇s tau-b相关分析显示,MGMT与hMLH1在胃癌组织中的表达呈正相关,r=0.370,P＜0.000 5.胃癌组织MGMT高表达或hMLH1高表达患者术后生存期要好于MGMT低表达或hMLH1低表达患者术后生存期,并且差异有统计学意义.结论：MGMT或hMLH1的表达与胃癌的发生密切相关,均具有抑制胃癌发生及发展的作用.

Expressions and the clinical significance of MGMT, hMLH1 in human gastric carcinoma

OBJECTIVE:To study the expressions and correlation of MGMT and hMLH1 in gastric carcinoma tissues, and at the same time, to investigate the relationship between their expressions and the clinicopathological features of gastric carcinoma studied. METHODS: We investigated the expression of the DNA repair enzyme that protected against alkylating mutagens, O6-methylguanine DNA methyltransferase (MGMT), and the mismatch repair (MMR) enzyme hMLH1 in 96 gastric cancer specimens by immunohistochemical means. The relationship between clinicopathologic features and expressions of MGMT and hMLH1 proteins were studied. RESULTS: The positive rates of MGMT and hMLH1 proteins in gastric carcinoma were 74%(71/96) and 65.6%(63/96), respectively. And there were significant differences about the expressions of MGMT and hMLH1 proteins in the clinicopathological factors, such as histologic classification, infiltrating depth, lymph nodes metastasis, TNM stages and recurrence or metastasizing after the operation (P<0.05). Both MGMT and hMLH1 expressions were not related to age and sex. Kendall's tau-b analysis indicated that the expressions of MGMT and hMLH1 in the gastric carcinoma were positive related each other (r=0.370,P<0.000 5). The survival curve showed that a loss of MGMT or hMLH1 was correlated with a poor prognosis. Combined evaluation of MGMT and hMLH1 revealed that the survival of patients with negative status for MGMT and hMLH1 was poorer. CONCLUSION: The expressions of MGMT and hMLH1 may be related to the carcinogenesis and progression, and have inhibitory effects on the carcinogenesis and progression of gastric carcinoma.