IGF1 and colorectal carcinoma: Many studies have reported the functions of histone variants in CRC 63, and various dysregulated genes related to CRC prognosis have also been reported: For example, high expression levels of CXCR2, IGF1, IL1A, OSM, and PLA2G4A, and hypermethylated MAPT were associated with poor prognosis 64-69; low expression levels of GFAP and PLA2G2A were associated with poor prognosis 70, 71.