In summary this study shows that combined inhibition of HDAC and BET proteins has synergistic effects in the treatment of melanoma in vitro and in vivo which are associated with more marked increases in upregulation of the pro-apoptotic protein BIM and downregulation of the anti-apoptotic proteins Bcl-2, Bcl-XL and XIAP than seen with the single drugs alone. The gene discussed is XIAP; the disease is melanoma.