人大肠癌组织中Smad4蛋白的表达和微血管密度检测

Detection of expression of Smad4 and MVD in human colorectal cancer tissue

目的:探讨大肠癌组织中Smad4蛋白的表达和微血管密度(MVD)的关系。方法:采用免疫组化SP法,检测64例大肠癌组织(其中结肠癌34例,直肠癌30例;高中分化腺癌42例,低分化腺癌22例;Dukes分期AB期36例,CD期28例;浸润深度在肌层以内者25例,浸润已达浆膜或超过浆膜者39例;有淋巴结转移者37例,无淋巴结转移者27例)和10例经病理证实为正常的癌旁大肠组织中Smad4蛋白的表达情况,并选取CD34标记血管内皮细胞测定MVD。结果:64例大肠癌组织中Smad4蛋白的阳性率为46.88%,10例正常大肠组织中Smad4蛋白的阳性率为90.00%,2组相比差异有统计学意义(P<0.05)。MVD在大肠癌组织及正常大肠组织中分别为26.85±8.27,8.83±4.94,二者差异有统计学意义(t=-8.987,P=0.000)。大肠癌组织中浸润深度达到或超过浆膜层,Dukes分期CD期和有淋巴结转移的大肠癌组织Smad4的阳性率明显低于浸润深度在浆膜以内,Dukes分期AB期和无淋巴结转移的大肠癌组织,差异均有统计学意义(P<0.05);Smad4表达阳性组MVD明显低于Smad4表达阴性组(P<0.01)。结论:Smad4的低表达与大肠癌的发展,生物学行为和预后可能有关,可作为重要的生物学标志。

Aim ： To examine the expression of Smad4 protein in colorectal cancer tissue and its association with angiogenesis. Methods：The expression of Smad4 and MVD were detected using immunohistochemistry in 10 cases of normal mocosa sample and 64 cases of colorectal carcinoma including 34 cases of colon carcinoma and 30 cases of rectum carcinoma; 36 cases of Dukes A-B stages and 28 cases of Dukes C-D stages ; 42 cases of highly-moderately differentiation and 22 cases of poorly differentiation ; 39 cases with infiltration into serosal layer or whole layer and 25 cases without infiltration into serosal layer; 37 cases with lymph node metastasis and 27 cases without lymph node metastasis. Results：The positive rates of Smad4 in colorectal carcinoma group and normal group were 46.88% and 90.00%. There were significant differences between the two groups （ P 〈 0.05 ）. MVD in colorectal carcinoma group and normal group were 26.85 ± 8.27,8.83 ± 4.94, respectively, and there were significant differences between the two groups （ P 〈 0.05）. The positive rates of Smad4 were significantly lower in the tissue of Dukes C-D stages, with infiltration into serosal layer or whole layer and with lymph node metastasis than that of Dukes A-B stages, without infiltration into serosal layer and without lymph node metastasis （ P 〈 0.05）. MVD in Smad4-positive group was significantly lower than that in Smad4-negative group （ P 〈 0.01 ）. Conclusion： Smad4 may be associated with the carcinogenesis, biological behavior and prognosis of colorectal cancer, and can be used as important biological markers in colorectal cancer.