OBJECTIVETo investigate the role of tissue factor (TF) expression in the invasive and metastatic ability of colorectal carcinoma and explore the influence of TF on the invasive ability of HT-29 cells.

METHODSTF expression of specimens from 85 colorectal carcinomas and 6 colorectal adenomas was observed by immunohistochemistry. The role of TF expression in prognosis and tumor invasion and metastasis was analyzed. The plasmids pcDNA3.1/Zeo bearing either sense or antisense-TFcDNA were transfected into HT-29 cells by the way of Lipofectamine 2000. TF proteins in transfected and untransfected HT-29cells were detected by Western blot. In vitro Matrigel invasion assays were performed to show the invasive ability of those cells.

RESULTSTF expression was positive in 40 (47.1%) of 85 colorectal carcinoma specimens, but negative in normal mucosa and adenoma specimens. TF expression showed significant correlation with tumor invasive depth (r = 0.895, P < 0.01). TF expression showed significant correlation with synchronous and metachronous hepatic metastasis (r = 0.974, P < 0.01 and r = 0.963, P < 0.01 respectively). TF expression was a significant risk factor for hepatic metastasis (P < 0.01) and prognosis (P < 0.01). TF expression in HT-29 cells with sense/antisense-TFcDNA transfection was more/less than that of the cells without transfection. The invasive ability of HT-29 cells with sense-TFcDNA transfection was increased in vitro compared with the untransfected cells, but HT-29 cells with antisense-TFcDNA transfection got the contrary change.

CONCLUSIONSTF may take part in the invasive and metastatic process of primary colorectal carcinoma, and TF expression may be an indicator of hepatic metastasis and prognosis for colorectal carcinoma patients. TF expression may increase the invasive ability of HT-29 cell in vitro.