CASP9 and neoplasm: Mechanisms of its pro-tumor effects include promoting tumor cell proliferation, apoptosis, invasion and migration by regulating antiapoptotic protein levels [13, 14], modulating the endoplasmic reticulum stress pathway [13], the mitogen-activated protein kinase (MAPK) pathway [5], the tumor necrosis factor-α (TNF-α) pathway [15] and the Bax/Bcl-2/caspase-9/caspase-3 pathway [6].