DCC基因在大肠癌中的表达及与Bcl-2, Bax关系

目的：探讨DCC(deleted in colorectal carcinoma)基因在大肠癌组织中的表达情况及与Bcl-2，Bax蛋白之间的关系。 方法：采用免疫组织化学法结合图像分析技术观察74例大肠癌组织中DCC，Bcl-2，Bax蛋白的表达情况。 结果：大肠癌组织中，DCC蛋白失表达率为 54.1% (40/74)，其表达在不同的肿瘤分化程度 (P＝0.002)及Dukes分期中有差异 (P＝0.042)； Bcl-2蛋白表达阳性率为60.8% (45/74)，其表达与不同的大肠癌临床Dukes分期 (P＝0.032)及是否有淋巴结转移 (P<0.001)中有差异；Bax蛋白表达阳性率为48.6% (36/74)，在不同的大肠癌组织学类型、分化程度、Dukes分期及淋巴结是否转移中均无差异 (P>0.05)。大肠癌中DCC蛋白表达与Bcl-2表达水平呈负相关（r＝－0.201, P＝0.043），与Bax表达水平呈正相关（r＝0.296, P＝0.005）。 结论：大肠癌中DCC表达缺失频率较高，且可能通过上调Bcl-2蛋白表达和下调Bax蛋白表达阻止细胞凋亡，从而促进大肠癌发生。

Detection of DCC expression in colorectal carcinomas and its relationshiop to Bcl-2, Bax

ObjectiveTo study the expression of deleted in colorectal carcinoma(DCC) protein and its relationship to Bcl-2 and Bax in human colorectal carcinoma.MethodsSeventy-four cases of primary carcinoma were studied by streptavidin peroxidase immunohistochemical technique and image analysis. ResultsNegative rate of DCC protein was 54.1%(40/74), DCC expression had significantly difference with degree of the differentiation (P＝0.002)and Dukes stage (P＝0.042); Positive rate of Bcl-2 protein was 60.8% (45/74), Bcl-2 expression had significantly difference indifferent Dukes stage (P＝0.032) and lymphoma metastasis (P<0.001); Positive rate of Bax protein was 48.6 % (36/74), no correlation was found between Bax expression and the clinical pathological parameters of colorectal carcinomas. DCC expression significantly positively correlated with Bax (r＝0.296, P<0.01), and negatively correlated with Bcl-2 (r＝－0.201, P<0.05). ConclusionLoss or downregulation of DCC protein expression is a frequent event，which possibly plays a role in colorectal carcinoma by upregulating Bcl-2 protein and downregulating Bax protein.