Potentiation of Invasive Capacity of Rat Ascites Hepatoma Cells by Transforming Growth Factor‐β

The in vitro invasive capacity of poorly invasive cells (W(1)), which were cloned from rat ascites hepatoma cells (AH 130), was potentiated dose‐ and time‐dependently by pretreating the cells with transforming growth factor‐β (TGF‐β). This potentiation of invasive capacity was completely abolished by anti‐TGF‐β antibody. When the treated cells were ip inoculated into rats, the cells extensively invaded the peritoneum, and formed penetrating tumor nodules. The effect of TGF‐β was reversed by subculturing the treated cells without TGF‐β. The potentiation of invasive capacity by TGF‐β might participate in platelet‐associated enhancement of tumor cell metastasis.