Data from breast and prostatic cancer cell studies indicate that Fgf8 transcription is, in part, under the regulatory control of androgen signaling through androgen receptors (AR) (Evans, 1988; Ohuchi et al., 1994; Yamanishi et al., 1995; Gnanapragasam et al., 2002; Tanaka et al., 2002). This evidence concerns the gene FGF8 and prostate carcinoma.