EGFR and colorectal cancer: The EREG (epiregulin) gene can function as a ligand of EGFR (epidermal growth factor receptor), as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors and is known to be associated to diseases like colorectal cancer, and hypopharynx cancer.