胃癌及癌前病变胃黏膜和胃腺瘤中APC基因表达及其意义

目的 探讨结肠腺瘤性息肉病（APC）基因在胃癌及胃腺瘤发生、发展中的重要作用以及其在胃癌早期诊断中的意义。方法 运用免疫组化技术检测APC基因蛋白在30例胃癌，30例不典型增生，30例肠上皮化生（肠化）和10例胃腺瘤，30例正常胃黏膜组织中的表达。结果 APC基因蛋白阳性表达率在胃腺瘤（50％），肠化（66．7％），不典型增生胃黏膜组织（53．3％）及胃癌（60％）中比正常胃黏膜（90％）明显降低（P〈0．05）。在中重度不典型增生胃黏膜组织中APC基因表达率（30．8％）比在轻度不典型增生中（70．6％）低（P〈0．05）。APC基因在中分化腺癌组表达率与低分化组比较差异有统计学意义（38．5％vs 83．3％，P=0．0287）。肠型胃癌中APC基因的表达率比在弥漫型胃癌低（47．6％vs 88．9％，P=0．0401）。结论 APC基因的失活在胃腺瘤的发生中起重要作用。APC基因的失活是胃癌发生的早期事件，APC基因蛋白表达产物的检测对早期胃癌的诊断可能是一项比较有价值的指标。

The study on the significance of APC gene expression in gastric cancer, precancerous lesion and gastric adenoma

Objective To investigate the role of the expression of APC gene in the progress of gastric cancer and gastric adenoma and the significance of the APC gene expression in the diagnosis of early gastric cancer.Methods Immunohistochemistry technology was applied in 30 cases with human gastric cancer(GC),30 cases with intestinal metaplasia(IM),30 cases with dysplasia(Dys) gastric mucosa,10 cases with gastric adenoma(GA) and 30 cases with normal stomach mucosa.Result The positive expression rates of APC in GC,IM,Dys and GA(60%,66.7%,53.3% and 50%,respectively) were significantly lower than those in normal gastric mucosa(90%,P<0.05).The positive rate of APC in moderate and severe Dys(30.8%) were lower than that in mild Dys(70.6%,P<0.05).The expression of APC was significantly lower in the moderate differentiation GC than that in the poor differentiation GC(38.5% Vs 83.3%,P=0.0287).The expression of APC was significantly lower in intestinal type GC than that in diffuse type GC(47.6% Vs 88.9%,P=0.0401).Conclusion It was important that APC gene lose of function in the occur GA.APC gene loss of function was an early event in the progress of GC.Detection of APC gene expression may be a valuable index to diagnose the early GC.