RIPK3 and cancer: To identify the function of Ppm1b in necroptosis in different cancer lines, we tested the expression of Ppm1b in normal human colon cell line FHC, HT29 and SW480, and breast cancer cells MDA-MB-231, MCF-7, and MDA-MB-453, we found that 3-BP could inhibit the expression of Ppm1b in MDA-MB-231 cells, with up-regulated expression of TNF-α and p-RIP 3, while no significant change in expression of RIP3 in MCF-7 cells (Figures 3A, B).