FAP and colorectal carcinoma: To investigate the role of integrin αvβ6 in regulating active fibroblasts, we co-cultured CCD-18Co fibroblasts with the above-mentioned four types of CRC cells for 96 h, and followed by RT-PCR and Western blotting to detect the mRNA and protein expression, respectively, of α-SMA and FAP in fibroblasts.