E-钙粘蛋白在进展期大肠癌转移淋巴结癌细胞中再表达的机制  

Re-expression of E-cadherin in metastatic lymph nodes of patients with advanced colorectal carcinoma

作　　者：李冬斌[1] 李晓宁[2] 许香梅[3] 段国强[1] 王影[1] 陈晓峰[4] 王凤安[1] 

机构地区：[1]河北医科大学第二医院胃肠外科,河北省石家庄市050000 [2]河北大学第二医院,河北省保定市071000 [3]河北省石家庄市第一医院,河北省石家庄市050011 [4]河北省保定市第二中心医院外科,河北省保定市072750

出　　处：《世界华人消化杂志》2010年第24期2545-2551,共7页World Chinese Journal of Digestology

摘　　要：目的:探讨E-钙粘蛋白(E-cad)在大肠癌转移淋巴结中的再表达机制及临床价值.方法:采用免疫组织化学SP法,Western blot,逆转录-多聚合酶链反应(RT-PCR)等方法联合检测32例大肠癌患者原发灶及相应转移淋巴结中E-cad的表达.结果:免疫组织化学结果显示:大肠癌原发灶中E-cad的异常表达率为90.6%(29/32).在转移淋巴结中,37.5%(12/32)E-cad再表达阳性,其中在高中分化、低分化腺癌E-cad再表达阳性率分别为55.6%(10/18)、14.3%(2/14),差异显著(P<0.05).Western blot结果显示:转移淋巴结组织中E-cad蛋白相对强度高于原发癌组织(P<0.05),但低于正常大肠黏膜(P<0.05).在转移淋巴结中,E-cad在高中分化、低分化腺癌蛋白相对强度分别为28-127(98.56±36.09)、11-62(66.21±29.74),差异显著(P<0.05).管状及乳头状腺癌转移淋巴结中E-cad蛋白相对强度高于黏液腺癌转移淋巴结(P<0.05).RT-PCR结果显示:大肠癌原发灶E-cad mRNA表达量相对值明显低于在正常大肠黏膜的表达量(0.733±0.009vs0.796±0.016,P<0.05);大肠癌转移淋巴结中E-cad mRNA表达量相对值明显高于在大肠癌原发灶的表达量(0.739±0.010vs0.733±0.009,P<0.05),但低于正常大肠黏膜表达量(P<0.05).高中分化腺癌转移淋巴结中E-cad mRNA表达量相对值高于低分化腺癌转移淋巴结(P<0.05),管状及乳头状腺癌转移淋巴结中E-cad mRNA表达量高于黏液腺癌转移淋巴结(P<0.05).结论:大肠癌发生发展过程中E-cad在基因及蛋白水平的表达存在一定的变化特征,这种特征可能使其成为大肠癌诊断与治疗的新靶点.AIM：To investigate the re-expression of E-cadherin（E-cad）in metastatic lymph node of advanced colorectal carcinoma and its clinical importance.METHODS：The expression of E-cad in 32 specimens of primary colorectal carcinoma and meta-static lymph nodes was examined by means of immunohistochemistry,Western blot and RTPCR to analyze the mechanism behind the reexpression of E-cad in metastatic lymph nodes.RESULTS：The abnormal expression rate of E-cad in primary colorectal carcinoma was 90.6%（29/32）,and the re-expression rate of E-cad in metastatic lymph nodes was 37.5%（12/32）.The re-expression rate of E-cad in metastatic lymph nodes was signifi cantly higher in patients with well/moderately differentiated carcinoma than in those with poorly differentiated carcinoma（55.6% vs 14.3%,P 0.05）.Western blot analysis showed that the relative expression intensity of E-cad in metastatic lymph nodes was higher than that in primary carcinoma（P 0.05）.The relative expression intensity of E-cad protein in metastatic lymph nodes was signif icantly higher in patients with well/moderately differentiated adenocarcinoma than in those with poorly differentiated adenocarcinoma（98.56 ± 36.09 vs 66.21 ± 29.74,P 0.05）.The relative expression intensity of E-cad protein in metastatic lymph nodes is correlated with tumor histological type.RT-PCR analysis showed that the relative expression level of E-cad mRNA in primary carcinoma was significantly lower than that in metastatic lymph nodes and normal mucosal tissue（0.733 ± 0.009 vs 0.739 ± 0.010 and 0.796 ± 0.016,both P 0.05）.The re-expression of E-cad mRNA in metastatic lymph nodes is associated with tumor differentiation degree and tumor histological type（both P 0.05）.CONCLUSION：E-cad expression shows characteristic changes during the development and progression of colorectal cancer.E-cad is a possible new target for diagnosis and treatment of colorectal cancer.

关 键 词：E-钙粘蛋白 人进展期大肠癌 转移淋巴结 再表达 免疫组织化学 蛋白免疫印迹 逆转录-多聚合酶链反应 

分 类 号：R735.34[医药卫生—肿瘤]