“…Although several RTK signaling factors, including PDGF, IGF, EGF and HGF, can promote lens cell proliferation in vitro, only FGFs can induce lens cell differentiation in mammals (Choi et al, 2004;Hyatt and Beebe, 1993;Kok et al, 2002;Liu et al, 1996;McAvoy and Chamberlain, 1989;Reddan and Wilson-Dziedzic, 1983;Wormstone et al, 2000). In transgenic mice, misexpression of the secreted forms of Fgf1,3,4,7,8 or 9 led to premature differentiation of lens epithelial cells into fiber cells, whereas dominant-negative Fgfr1 suppressed lens epithelial cell proliferation (Faber et al, 2001;Lovicu and Overbeek, 1998;Robinson et al, 1998;Robinson et al, 1995).…”