ERBB3 and cancer: Target drugs are expected to bind these abnormal receptor proteins, inhibit their activity, and inhibit cancer cell growth.[16, 17, 18] Therefore, anticancer drugs such as afatinib (AFT), which irreversibly binds to the ErbB family of receptors (including four different cancer cell receptors EGFR, HER2, ErbB3, and ErbB4), have become targets for mutant EGFR challenge.[19] A highly effective drug blocks the growth of cancer cells.