We initially performed immunohistochemical (IHC) analysis of ECSIT expression in intestines of Apcmin/+ mice (which are heterozygous for the gene encoding adenomatous polyposis coli [Apc] and develop multiple intestinal neoplasia).[20] We demonstrated that ECSIT expression was significantly down‐regulated in tumor tissue compared to their unaffected counterpart peri‐tumor tissue (Figure S16D, Supporting Information). The gene discussed is APC; the disease is neoplasm.