ERBB2 and colorectal carcinoma: Moreover, the EGFR family includes three additional members (ERBB2, −3 and −4), often expressed by CRC cells and able to form any kind of functional heterodimers upon binding to two distinct ligand families (EGF‐like factors, binding to EGFR, and neuregulins binding to ERBB3 or −4) [44].