XIAP and non-small cell lung carcinoma: Despite the studies of several possible regulators of apoptosome in NSCLC cells, including the inhibitor of apoptosis proteins XIAP, cIAP-1 and cIAP-2, TUCAN, Smac, and PHAPI (28–32), and the evidence of high-Mr apoptosome complexes incapable of PC-9 processing (33–35), the regulation of apoptosome assembly and signalling in NSCLC is still elusive.