FOXA1 (HNF3A, Hepatocyte nuclear factor 3- alpha) is member of the Forkhead family of winged-helix transcription factors. It is known to be involved in the development and differentiation of several organs including liver, kidney, pancreas, lung, prostate and mammary gland (Lupien, 2008). High expression of FOXA1 is often seen in tumors arising from both the prostate and breast where it is believed to interact with either the androgen receptor or estrogen receptor alpha, in each of the tumor type respectively (Lupien, 2008). In the case of ERa, FOXA1 has gained notice because of its interactions with the cis- regulatory regions in heterochromatin and because it enhances the interaction of ERa with chromatin (Badve, 2007).