Antigen selection observes specific rules: (1) to facilitate ADCs acknowledgement, the antigen should be extracellular; (2) the antigen should be non-secreted, preventing major side effects with a minor antigen expression in tumor cells; (3) related to ADCs approved or under investigations, antigens are specific proteins presented by solid tumors, such as HER2, trop2, nectin4 and EGFR [8]. The gene discussed is ERBB2; the disease is neoplasm.