RIPK3 and neoplasm: Extensive loss/reduction of RIPK3 expression in many cancers suggests its loss provides some kind of selective advantage to tumor cells,[9a] while previous characterization of RIPK3 knockout mice did not observe spontaneous tumor formation in these studies.[18] We therefore sought to define the role of RIPK3 in tumor suppression by using Ripk3−/− mice where the tumor‐promoting/enhancing conditions might be more readily seen, such as in carcinogen‐induced models or in models where other tumor suppressors were lost.