BCL2 and cancer: ABT-737, a predecessor of orally applicable ABT-263 was prepared by nuclear magnetic resonance (NMR)-assisted structure-based modulation of a compound selected from a chemical library that strongly interacted with the BH3-binding hydrophobic groove of BCL-XL/BCL2 and induced apoptosis of various human cancer cell lines at submicromolar concentration (Figure 2) [63].