Further, CRC is classified into four CMSs with distinct molecular and biological features: CMS1 (microsatellite instability immune; enriched for MSI tumors and BRAF-mutations), CMS2 (canonical; epithelial characteristics with marked WNT and MYC signaling and high CIN), CMS3 (metabolic; epithelial features but less CIN, enriched for KRAS mutations, evident metabolic dysregulation), and CMS4 (mesenchymal; prominent TGF-β activation, stromal invasion, angiogenesis, inflammatory, immunosuppressive phenotype) [33]. This evidence concerns the gene KRAS and colorectal carcinoma.