Bif-1 and Bax expression in cutaneous Merkel cell carcinoma.

Background: Bax-interacting factor-1 (Bif-1) binds to Bax, which in turn activates this proapoptotic protein. In the absence of Bif-1, the ability to induce apoptosis through the intrinsic pathway is greatly reduced. Merkel cell carcinoma (MCC) classically shows an aggressive behavior and lack of response to chemotherapy, which remains unexplained.