Bcl-xL、Bax和Bcl-2蛋白在大肠癌伴血吸虫病中的表达及其意义

Bcl-x L, Bax and Bcl-2 expressions in colorectal carcinoma associated with schistosomiasis

目的检测Bcl-x L、Bax和Bcl-2蛋白在大肠癌伴血吸虫病中的表达,探讨血吸虫感染与大肠癌之间的可能发病机制。方法 76例大肠癌患者分为两组,大肠癌伴血吸虫病组40例及单纯大肠癌组36例。用免疫组化SP法检测Bcl-x L、Bax和Bcl-2蛋白在两组患者中的表达水平。肿瘤HE切片在显微镜下观察细胞形态并进行凋亡率统计。结果在大肠癌伴血吸虫病组及单纯大肠癌两组中,Bcl-x L蛋白的表达强度均为中等,阳性率分别为50.0%,66.7%(P>0.05);在大肠癌伴血吸虫病组中,Bax蛋白的表达强度为中度,阳性率为25.0%,而在单纯大肠癌组中的表达强度为中到强阳性,阳性率为77.8%(P<0.001);Bcl-2蛋白在大肠癌伴血吸虫病组中的表达强度为弱到中度,阳性率为55.0%,而在单纯大肠癌组中的表达强度较弱,阳性率为22.2%(P<0.05)。大肠癌伴血吸虫病组及单纯大肠癌两组的细胞凋亡率分别为15.0%、42.0%(P<0.001)。结论慢性日本血吸虫病与大肠癌之间可能存在一定的关系;在慢性血吸虫病引起的肠粘膜的恶变过程中,Bcl-2和Bax的异常表达,引起凋亡的失调,从而导致肿瘤的发生、发展。

Objective To investigate the relationship between chronic schistosomiasis japonica and colorectal carcinomathrough detecting the expression pattern of Bcl-x L, Bax and Bcl-2 in colorectal carcinoma with schistosomiasis.Methods We divided the colorectal cancer patients in two different groups, one associated with Schistosoma and the otherwithout Schistosoma. The expression of Bcl-x L, Bax and Bcl-2 was detected in 40 cases of colorectal cancer with Schistosoma and 36 colorectal cancer without Schistosoma by S-P immunohistochemical technique, in addition the apoptotic activity ofthese tumor cells were analyzed by HE. Results The immunostaining intensity of Bcl-x L protein in colorectal cancer with Schistosoma and colorectal cancer without Schistosoma were moderate, the positive percentage of Bcl-x L expression incolorectal cancer with Schistosoma group was 50.0%, and it was 66.7% in control group（P0.05）;In colorectal cancer with Schistosoma, the immunostaining intensity of Bax protein was moderate, the positive percentage was 25.0%, and it wassignificantly lower than the control group（77.8%）（P0.001）. The immunostaining intensity of Bcl-2 protein in two groups wereweak, the positive percentage of Bcl-2 expression in colorectal cancer with Schistosoma was 55.0%, and it was significantlyhigher than the control group（22.2%）（P0.05）. Apoptotic activity was more evident in colorectal cancer without Schistosoma group（42.0%） than that of the other group（15.0%）（P0.001）. Conclusion There might be a high correlation between chronicschistosomiasis japonica and colorectal carcinoma. These observations suggest that the genotoxic agents may play a role incolorectal cancer with Schistosoma pathogenesis through the dysregulation of apoptosis by alteration the expression pattern ofBcl-2 and Bax protein differently from colorectal cancer without Schistosoma.