BIRC3 and neoplasm: Although the expression of c-IAP1 and c-IAP2 is not tumor-specific, their overexpression can suppress chemotherapy-induced apoptosis in vitro.[29] Kempkensteffen et al.,[29] performed quantitative RT-PCR for c-IAP1 and c-IAP2 in 104 nephrectomized specimens and demonstrated that the tumor-to-normal ratio of c-IAP1 was a prognostic factor, especially in pT3 tumors.