Similar results were obtained for XIAP-deficient NEC cells that demonstrated an impaired average tumor growth [NEC-DUE1: 111.1 mm3 (± 25.72) versus control: 279.8 mm3 (± 38.5), (p = 0.008) and NEC-DUE2: 284.9 mm3 (± 57.95) versus control 603.9 mm3 (± 109.8), p = 0.027)] and reduced average tumor weight (NEC-DUE1: 0.06 g (± 0.01) versus control 0.09 g (± 0.01), (p = 0.023) and NEC-DUE2: 0.31 g (± 0.06) versus control 0.52 g (± 0.07), p = 0.039) (Figure 2E and Supplementary Figure 2E and 2F). Here, XIAP is linked to neoplasm.