Among all pro-survival BCL-2 proteins, only BCL-2, BCL-xL and BCL-W are bound with relevant affinities by ABT-737 and ABT-263.38, 39 Accordingly, resistance of tumor cells is commonly caused by high levels of MCL-1 and/or BFL1/A140 and thus targeting these two proteins has become increasingly interesting. Here, BCL2 is linked to neoplasm.