MCL1 and cancer: Overexpression of anti-apoptotic or pro-survival proteins of the Bcl family such as Bcl 2, B-cell lymphoma-extra large (Bcl-xL), myeloid cell leukemia 1 (Mcl-1), Bcl-2-like protein 2 (BCL2L2 or Bcl-w) and Bcl-2-related protein A1 (A1/Bfl-1) has been reported to be present in cancer [45].