结直肠癌组织中成纤维细胞激活蛋白的表达及临床意义

Expression and clinical significance of fibroblast activation protein in colorectal carcinoma tissue

目的探讨成纤维细胞激活蛋白（FAP）在结直肠癌组织中的表达及其与各病理学指标之间的关系。方法应用免疫组织化学染色法检测55例结直肠癌组织和50例正常结直肠组织中FAP的表达，观察阳性细胞在不同组织中的分布数量，结合肿瘤分期、有无淋巴结转移及不同浸润深度等病理学指标，评价FAP表达与结直肠癌病理特征的相关性。结果正常结直肠组织中几乎无FAP表达，少数癌细胞有微弱表达。FAP阳性细胞主要为结直肠癌间质组织中的肿瘤相关成纤维细胞（CAFs）。TNMⅢ～Ⅳ期标本中FAP阳性细胞为（40．1±15．9）个，多于Ⅰ-Ⅱ期的（18．3±7．7）个（P〈0.01）；且阳性细胞数量与分期程度相关（r=0．544，P〈0．01）。淋巴结转移组中阳性细胞为（44．4±13．3）个，多于无淋巴结转移的（18．5±8．1）个（P〈0．01）；且阳性细胞数量与有无淋巴结转移相关（r=0．793，P〈0．01）。不同浸润深度T2、T1和T4组标本中FAP阳性细胞数分别为（25．2±8．9）、（32．4±19．3）和（29．2±16．5）个（P〉0．05）；阳性细胞数量与浸润深度无关（r=0．003，P〉0．05）。结论FAP在正常结直肠组织中无表达．而主要表达于结直肠癌组织中的CAFs中。FAP阳性细胞与结直肠癌的TNM分期及淋巴结转移相关。

Objective To detect the expression of fibroblast activation protein （FAP） in eoloreetal cancer tissue, and to investigate the association between expression of FAP with pathological parameters. Methods Fifty-five cancer tissues and 50 normal colorectal samples were examined using immunohistochemistry with anti-FAP polyclonal antibody. The distribution of positive cells in different tissues, and associations of positive cell number with tumor staging, lymph node metastasis and tumor invasion were investigated to evaluate the effects of FAP on pathological progress in colorectal cancer. Results No FAP expression was observed in 50 normal colorectal tissue samples. FAP positive cells were seen in carcinoma associated fibroblasts （CAFs）, and in few colorectal cancer cells. The numbers of FAP positive cells in tissue samples of TNM Ⅲ-Ⅳ （40.1±15.9） was significantly greater than that of TNM Ⅰ-Ⅱ （18.3±7.7） （P〈0.01）. Furthermore, the number of FAP positive ceils in tissue samples with lymph node metastasis （44.4±13.3） was also significantly higher than those without lymph node metastasis （18.5±8.1） （P〈0.01）. Significant possitive correlations were found between the number of FAP-positive cells with the tumor TNM staging and lymph node metastasis （r=0.544 and r=0.793, respectively） （P〈0.01）. The number of FAP-positive cells was 25.2±8.9 in T2, 32.41±19.30 in T3, and 29.2±16.5 in T4. The association between number of positive cells and depth of invation was not statistically significant（P〉0.05）. Conclusions The FAP mainly expresses in CAFs locating in colorectal cancer tissues. The number of FAP positive cells is positively correlated with TNM staging of colorectal cancer and lymph node metastasis.