TGFA and carcinoma: TGFα is expressed primarily in ectodermic and epithelial cells during normal development and is frequently up-regulated in carcinoma cells (Greten et al., 2001; Awwad et al., 2003; Calvisi and Thorgeirsson, 2005), and expression of TGFα can confer a transformed phenotype and tumorigenesis to normal cells (Derynck, 1990; Lee et al., 1995; Humphreys and Hennighausen, 2000; Shi et al., 2000).