SMAD4 and gastric cancer: The models that ranked #2-6 (GSE103639 (NGE vs pCP_GC), GSE45956, GSE103639 (NGE vs pChePS_GC), GSE16902, GSE93774) were all genetically engineered mouse models (GEMMs) in which targeted deletions were performed on genes (CDH1, SMAD4, CLDN18, etc.)that are associated with risk of GC, by virtue of being either the most common germline mutation in GC (CDH1 [43]), or for harboring disease-associated SNPs (SMAD4 [44]) or being the target of the most frequent somatic genomic rearrangements [45] (CLDN18).