Abstract: | Transforming growth factor type-e (TGFe) is a novel TGF which was first described as a growth factor possibly involved in autocrine stimulation of anchorage-independent growth of carcinoma cells. Its later identification in normal tissues, plasma, and platelets suggested a role for TGFe in normal cell growth. This study shows that TGFe stimulates both anchorage-dependent and -independent growth of epithelial and fibroblastic cells of nonneoplastic origin. The mitogenic activity of TGFe in monolayer is slightly less than that of basic fibroblast growth factor, equipotent to that of epidermal growth factor, and greater than that of IGF-1. TGFe acts as a progression factor for both AKR-2B and Balb-3T3 cells. TGFe is also a potent mitogen for normal human epidermal keratinocytes and may therefore play a role in epidermal growth and regeneration. |