Abstract:Objective:To investigate the effect of transforming growth factor-β1 on metastasis and invasion of gastric cancer and its mechansism. Methods :The changes of bilogical behaver of gastric cancer SGC7901 and BGC823 cell line were tested after pretreatment by TGFβ1 at 0 or 10 ng/mL,and liver metastasis was measured 4 weeks after inoculation in Balb/c nude mice. Results:SGC7901 and BGC823 cells treated with TGF-β1 had more hepatic metastases and the effect of penetrated reconstituted basement-membrane barriers increased significantly than that untreated control cells did. Likewise, there was an apparent increase in tumor cell migration and adhesion capacity after treating with TGFβ1. Conclusions:These results suggest that TGF-β1 may modulate metastatic potential of gastric cancer cells by promoting their ability to break down and penetrate basement membrane barriers and by their adhesive and motile activities. TGF-β1 acts on SGC7901 and BGC823 cells as a progression-enhancing factor.