Activin was initially described as a
protein that stimulates release of
follicle stimulating hormone from the pituitary, and it is well known for its important roles in different reproductive functions. In recent years, this multifunctional factor has attracted the attention of researchers in other fields, as new functions of
activin in angiogenesis,
inflammation, immunity,
fibrosis and
cancer have been discovered. Studies from our laboratory have identified
activin as a crucial regulator of wound healing and skin
carcinogenesis. On the one hand, it strongly accelerates the healing process of skin
wounds but, on the other hand, it enhances
scar formation and the susceptibility to skin
tumorigenesis. Finally, results from several laboratories have revealed that
activin enhances tumour formation and/or progression in some other organs, in particular through its effect on the tumour microenvironment, and that it also promotes
cancer-induced bone disruption and muscle wasting. These findings provide the basis for the use of
activin or its downstream targets for the improvement of impaired wound healing, and of
activin antagonists for the prevention and treatment of
fibrosis and of malignant tumours that overexpress
activin. Here, we summarize the previously described roles of
activin in wound healing and
scar formation and discuss functional studies that revealed different functions of
activin in the pathogenesis of
cancer. The relevance of these findings for clinical applications will be highlighted.