MUC1 and cancer: HzMUC1-MMAE is a humanized MUC-1 monoclonal antibody conjugated with monomethyl auristatin (MMAE, microtubule polymerization inhibitor) designed to target BC, as MUC-1 is overexpressed in a variety of cancers, and is a marker for anti-HER2 resistance as described previously [181].