大肠腺癌中细胞增殖周期调控因子p16和cyclin D_1的表达和意义

Expression and significance of cell division cycle regulators p16 and cyclin D_1 in human large intestinal adenocarcinoma

应用S－P免疫组织化学染色方法观察人大肠腺癌中细胞增殖周期调控因子p16和cyclinD1的表达和意义。结果表明，在良恶性细胞p16蛋白表达均位于细胞浆，CyclinD1蛋白表达主要位于细胞核。在大肠腺癌p16蛋白表达阳性率为49．2％，明显低于癌旁正常粘膜（789％），染色强度大部分为弱阳性或阳性（＋）。cyclinD1蛋白表达阳性率为67％，明显高于癌旁正常粘膜（28．9％），染色强度大部分为阳性（＋），强阳性（＋＋）。p16蛋白表达阳性率随大肠腺癌分化程度的降低而下降，与淋巴结转移无关。cyclinD1蛋白表达阳性率与大肠腺癌的分化程度、淋巴结转移均有关。本研究结果表明p16蛋白抑制肿瘤细胞增殖，而cyclinD1蛋白促进肿瘤细胞增殖这一细胞增殖周期调控机制，可能与大肠腺癌的发生发展有关。

Using streotavidin peroxidase immunohistochemical staining method was used to study the expression and significance of cell division cycle regulators p16 and cyclin D1 in cases with large intestinal adenocarcinoma.The results showed that the expression of p16 protein was located in cytoplasm, while the expression of cyclin D1 protein was located in nucleus in both benign and malignant cells. The positive rate of p16 protein in the large intestinal adenocarcinoma was 49. 2% (33/67), much lower than 78. 9% in normal colon mucosa, the intensity of staining of most sections was weak (±), but in some of them was strong (+ ). The positive rate of cyclin D1 protein was 67% (45/67), much higher than 28. 9% in normal colon mucosa, the intensity of staining of most sections was strong (+ ) and in some very strong (+ + ). The positive rate of p16 protein lowered with lower degree of differentiation in large intestinal adenocarcinoma, but it did not correlate with lymph node metastasis of the tumor. The positive rate of cyclin D1 was correlated with both the degree of differentiation and lymph node metastasis of the tumor. The results show that p16 protein can suppress tumor cell proliferation, but cyclin D1 protein can promote tumor cell proliferation. The mechanism of cell division cycle regulation is possibly related to the tumorigenesis of large intestinal adnocarcinoma.