BAK1 and myeloid leukemia: Therefore, our present findings identified GBP1 and GBP2 as novel apoptosis-inducing proteins in myeloid leukemia cells, which regulate both MCL-1 and BAK; these are two critical members of the BCL-2 protein family presenting opposite functions to regulate the fate of cells by forming or disrupting the heterodimeric complex of MCL-1-BAK.