CyclinD1基因扩增及其蛋白表达在大肠癌中的意义

Amplification of CyclinD1 gene and overexpression of its protein product in colorectal carcinoma

目的探讨大肠癌中CyclinD1基因扩增和其蛋白表达的相关性及其临床意义。方法应用差异聚合酶链反应(DPCR)和免疫组化技术检测分析70例大肠癌、距癌灶3cm以外的癌旁组织及距癌灶10cm以外的正常组织中CyclinD1基因扩增和CyclinD1蛋白的表达情况。结果70例大肠癌中CyclinD1基因扩增占31.4%(22/70),CyclinD1蛋白过度表达占51.4%(36/70),二者成正相关(P<0.01,r=0.473),而癌旁及正常组织中CyclinD1基因扩增及其蛋白表达分别为2.9%(2/70)、4.3%(3/70)和0.0%(0/70)、0.0%(0/70)。与大肠癌相比差异有显著性(P<0.01)。Cy-clinD1基因扩增及其蛋白表达在大肠癌中不同组织学类型、淋巴结有无转移及Dukes不同分期差异有显著性(P<0.05)。结论大肠癌中CyclinD1基因扩增及其蛋白表达虽有一定相关性,但并不完全一致,说明还存在着其它导致CyclinD1蛋白过度表达的机理,CyclinD1基因扩增及其蛋白过度表达在大肠癌的恶性进展中起重要作用,可作为判定大肠癌恶性度的重要参数之一。

Objective To investigate the clinical significance of the amplification of CyclinD1 gene and overexpression of its protein product in colorectal carcinoma. Methods Differential polymerase chain reaction （DPCR） and immunohistochemical techniques were used to examine the amplification of CyclinD1 gene and overexpression of its protein product in 70 colorectal carcinomas, pericareinoma and normal tissues. Results The results showed that amplification of CyclinD1 gene was observed in 22 out of 70（31.4% ） colorectal carei- noma, the overexpression of its protein product was 51.4% （36/70）. Compared with pericareinoma and normal tissues, these findings were significant, and there was a strong correlation between the amplification of CyclinD1 gene and overexpression of its protein product in colorectal carcinoma. The amplification and overexpression of CyclinD1 gene in colorectal carcinoma were closely related to the tumor differentiation, lymphnode metastasis and Dukes stages. Conclusion The degree of CyclinD1 protein overexpression is not quite the same as the frequen- cy of the amplification of CyelinD1 gene. It suggests that the overexpression of CyclinD1 protein is also attributed to some other mechanisms. The status of high amplification and overexpression of CyclinD1 gene may play an im- portant role in the malignant progression of colorectal carcinoma, and may be as one of the important markers for judging the malignant extent of eolorectal carcinoma.