ERBB2 and breast carcinoma: For instance, many HER2-positive breast cancers do not respond to trastuzumab treatment (de novo resistance), while many trastuzumab-responsive patients develop resistance after continuous trastuzumab infusion within one year (acquired resistance) [18,19]; meanwhile, although the treatments have improved, the major problem in the hematological multiple myeloma (MM) is the resistance to therapy.