CDKN1B and colorectal carcinoma: Colorectal carcinoma and neuroblastoma cells treated with catalase also showed p27Kip1 localized primarily within the nucleus as compared with controls, in which p27Kip1 distribution was predominantly cytoplasmic (Figures 7A and 7B show treatments for 24 h and Figures S9A and S9B show treatments for 6h).