Activation of initiator caspase-9 after exposure to TRAIL or IR was reported in carcinomas of the prostate and lung (Nimmanapalli et al, 2001; Joseph et al, 2001; Sun et al, 2001), Ewing's sarcoma (Mitsiades et al, 2001) and Jurkat lymphoma cells (Kim et al, 2001a; Rudner et al, 2001). This evidence concerns the gene CASP9 and prostate carcinoma.