胃癌及胃癌前病变中APC、bcl-2和c-met基因的表达及意义

目的：探讨APC、bcl-2和c-met基因在胃癌发生、发展中的作用以及在胃癌早期诊断中的意义。方法：应用免疫组化技术检测APC、bcl-2、c-met蛋白在30例胃癌、30例不典型增生、30例肠上皮化生(肠化)、10例胃腺瘤及20例正常胃黏膜组织中的表达。结果：　①APC 阳性表达率在肠化、不典型增生、胃癌及胃腺瘤组织中表达率分别为66.7%、53.3％、53.3％和50.0%，与正常胃黏膜组织（90.0%）比较明显降低（P<0.05），其中中重度不典型增生APC表达率（47.1％）低于轻度不典型增生（61.5％）(P<0.05)。APC在无淋巴结转移的胃癌组织中表达率高于有淋巴结转移的胃癌组织（P<0.05）。② bcl-2阳性表达率在胃癌（66.7％）、不典型增生（43.3％）、肠化（40.0％）胃黏膜组织中表达率均明显高于正常对照组（5.0％）和胃腺瘤组（10.0％）（P<0.05）；轻度不典型增生组阳性表达率（30.8％）低于胃癌组 (P<0.05)；中重度不典型增生组（52.9％）与胃癌组比较差异无显著性 (P>0.05)。中高分化胃癌组织中bcl-2表达率者高于低分化者(P<0.05)， Lauren分型肠型胃癌中表达率高于弥漫型（P<0.05）。③ c-met阳性表达率在胃癌（63.3％）、肠化（63.3％）和不典型增生组织（60.0％）均明显高于正常胃黏膜组（10.0％）和胃腺瘤组（10.0％）（P<0.05）；中重度不典型增生组阳性表达率（70.6％）明显高于轻度不典型增生组（46.1％）（P<0.05）；中重度肠化组阳性表达率（75.0％）明显高于轻度肠化组（55.6％）（P<0.05）。中高分化胃癌c-met阳性表达率高于低分化胃癌(P<0.05)，有淋巴结转移者高于无淋巴结转移者（P<0.05）。结论：APC基因的失活、bcl-2和c-met基因的过表达对胃癌的发生、发展起促进作用;对中重度不典型增生胃黏膜进行APC、bcl-2和c-met基因检测有助于胃癌的早期诊断。

Expressions of APC, bcl-2 and c-met in gastric cancer and its precancerous lesion and their significances

Objective To investigate the role of the expressions of APC,bcl-2 and c-met gene in the progress of gastric cancer and their significances in the diagnosis of early gastric cancer.Methods The immunohistochemical technique was used to detect the expressions of APC,bcl-2 and c-met gene in 30 cases of human gastric carcinoma(GC),30 cases of intestinal metaplasia(IM),30 dysplasia(Dys) gastric mucosa,10 gastric adenoma(GA) and 20 normal gastric mucosa.Results ①The positive expression rates of APC in GC,IM,Dys and GA(53.3%,67.7% and 53.3%,respectively) were significantly lower than those in normal gastric mucosa(90.0%,P<0.05).The positive rate of APC in moderate and severe Dys(47.1%) was lower than that in mild Dys(61.5%,P<0.05).The expression rate of APC in GC without lymph node metastasis was higher than those with lymph node metastasis(P<0.05).②The positive expression rates of bcl-2 in GC(66.7%),IM(40.0%) and Dys(43.3%)were higher than those in normal gastric mucosa(5.0%) and GA(10.0%).The positive expression rate of bcl-2 in mild Dys(30.8%) was lower than those in GC(66.7%,P<0.05).The bcl-2 expression showed a significant negative correlation with lymph node metastasis and Lauren type(P<0.05).③The positive expression rates of c-met in GC(76.0%),IM(63.3%) and Dys(60.0%) were higher than those in normal gastric mucosa(10.0%,P<0.05)) and gastric adenoma(10.0%,P<0.05).The positive expression rate of c-met in moderate and severe IM(70.6%)was higher than those in mild IM(46.1%,P<0.05).The positive expression rate of c-met in moderate and severe Dys(75%) was higher than that in mild Dys(55.6%,P<0.05).The expression of c-met gene in GC with well differentiation was higher than that with bad differentiation(P<0.05).The expression of c-met gene in GC with lymph node metastasis was higher than that without lymph node metastasis(P<0.05).Conclusion The lose of APC or bcl-2 and c-met gene overexpression are contributed to the occurance and development of GC.To detect the expressions of APC,bcl-2 and c-met gene in moderate and severe Dys may be helpful for diagnosis of early gastric cancer.