TP53 and gastric cancer: The Asian Cancer Research Group (ACRG) classification categorizes GC into the following molecular subtypes: microsatellite stable/epithelial-mesenchymal transition (MSS/EMT); microsatellite unstable (MSI); microsatellite stable/tumor protein 53 active (MSS/TP53+); and microsatellite stable/tumor protein inactive (MSS/TP53−).