The study conducted by our group has also shown that silibinin induced apoptosis in human bladder cancer 5637 cells in vitro and in vivo, which was associated with the activation of cytochrome c (Cyto C)/caspase-dependent and AIF/caspase-independent pathways involving selective release of Omi/HtrA2 from mitochondria17. Here, HTRA2 is linked to urinary bladder cancer.