BIRC5 and colorectal cancer: In the present study, we aimed to examine cytotoxicity, apoptosis, cell cycle distribution, expression of IAPs Survivin, cIAP1, cIAP2 and XIAP and used the more physiologic three-dimensional (3D) clonogenic survival assay in three colorectal cancer cell lines, pretreated with BV6 followed by exposure to different doses of ionizing radiation.