BCL2 and neoplasm: Different classes of small-molecule drugs enforce the intrinsic mitochondrial pathway: On the one hand, by mimicking the natural antagonists of BCL-2 family survival proteins (so called BH3-mimetics or BCL-2 family inhibitors) or of the inhibitors of apoptosis (IAPs) (so called SMAC-mimetics); on the other hand, by directly targeting BCL-2 expression with antisense oligonucleotides—all sensitizing tumor cells to death [26].