SMAD4 and cancer: Among these cancer-related pathways, the TGF-β pathway has been found to be more frequently mutated in MSI colorectal cancer than in MSI endometrial cancer.[47] It is interesting that SMAD4, a member of the TGF- β pathway, was reported to be associated with a poorer prognosis in MSI-H CRCs, but not in MSS CRCs.[48,49] In endometrial cancers, however, the differential roles of SMAD4 in the prognosis depending on MSI status were not reported.