Fig. 5. Proposed mechanism of the cytoprotective effect of KGF. The cell-damaging effects of UV irradiation and of xenobiotics with electrophilic and oxidative properties are alleviated by KGF. Upon binding of KGF to its receptor signaling pathways are activated, which induces the expression of cytoprotective genes. A higher activity of cytoprotective proteins renders a cell more resistant against the cellular damage caused by UV irradiation, menadione, tBHQ and other substances.