ERBB2 and neoplasm: Doxorubicin (Dox), the conventional chemotherapy to reduce the number of MDSCs in tumor tissues and promote antitumor responses, is converted into a liposomal formulation to improve the efficacy of therapy, as well as the peptide named the E75 epitope (Pep) originating from human epidermal growth factor receptor 2 (HER2/neu).