RIPK3 and colorectal cancer: Serial paraffin cuts of tissue specimens from colorectal cancer patients with differential TRAF6 protein levels were subjected to immunohistochemical assays for the RIPK1 classical necroptotic pathway RIPK1-RIPK3-MLKL, and the protein levels of RIPK1, RIPK3, MLKL in human colorectal cancer tissues from the high level TRAF6 group was found to be significantly lower than that of the low expression TRAF6 group (Fig. 1h).