Bcl-2、Bcl-xL 和Bax在结直肠癌中的表达

目的:观察结直肠癌与癌旁组织中Bcl-2、Bcl-xL 和Bax的表达,探讨它们在结直肠癌发生发展中的可能作用.方法:RT-PCR、免疫组化MaxVision一步法分别检测40例结直肠癌组织与癌旁组织中Bcl-2、Bcl-xL 和Bax mRNA表达及其相应蛋白表达水平.结果:癌组织和癌旁组织的Bcl-2 mRNA及其蛋白表达水平都很低,两者之间无显著差异;两者Bcl-xL mRNA及蛋白表达水平均较高,且癌组织明显高于癌旁组织(P<0.05);两者Bax mRNA及蛋白表达水平均较Bcl-2、Bcl-xL高,但两者间无显著差异.两者Bcl-2/Bax和Bcl-xL/Bax的比值间无显著差异.Bcl-2蛋白表达与Dukes分期和TNM分期都呈负相关(P<0.05),与其他临床病理相关因素(性别、年龄、肿瘤大小、发生部位、组织学类型、分化程度)无明显相关;而Bcl-xL 、Bax在基因及蛋白水平的表达均与临床病理相关因素无关.结论:结直肠癌中Bcl-xL在基因及蛋白表达水平明显强于Bcl-2,且明显高于癌旁组织;前者可能促进了肿瘤的发生发展.Bcl-2蛋白表达与肿瘤分期呈负相关,可作为评价结直肠癌临床预后的参考指标.

Expression of Bcl-2,Bcl-xL and Bax in colorectal carcinomas

Objective:To observe the expression of Bcl-2,Bcl-x_(L) and Bax in colorectal cancer tissues and their corresponding adjacent tissues(>5 cm from the tumor tissue),and to study their roles in the development and progression of colorectal cancer.Methods: The mRNA levels of Bcl-2,Bcl-x_(L),Bax were detected by RT-PCR and their protein levels were detected by MaxVision one step method in 40 colorectal cancer tissues and their corresponding adjacent tissues.Results: The mRNA and protein levels of Bcl-2 were very low in both cancer tissues and adjacent tissues(P>0.05).Both cancer tissues and adjacent tissues had higher Bcl-x_L mRNA and protein levels,with those of the cancer tissues obviously higher than those of the adjacent tissues(P<0.05).The levels of Bax mRNA and protein were higher than those of Bcl-2 and Bcl-x_(L) in both tissues,but with no significant difference between the 2 tissues.The ratio of Bcl-2/Bax and Bcl-x_(L)/Bax in 2 tissues had no significant difference,either.The expression of Bcl-2 protein was negatively correlated with Dukes and TNM stages of the colorectal cancer((P<0.05),) and was not correlated with other factors such as sex,age,tumor size,tumor location and morphological types.Levels of mRNA and protein of Bcl-x_(L) and Bax were not correlated with pathological factors.Conclusion: Bcl-x_(L) expression is obviously higher than that of Bcl-2 in colorectal tissues and also higher than that of Bcl-x_(L) in adjacent tissues,suggesting that Bcl-x_(L) may enhance the development and progression of colorectal cancer.Bcl-2 may be a prognostic indicator for colorectal cancer because it is negatively correlated with tumor stages.