Nanoliposomes carrying HER2/neu-derived peptide AE36 with CpG-ODN exhibit therapeutic and prophylactic activities in a mice TUBO model of breast cancer

•Synthesis of liposomes formulations containing AE36 HER2/neu-derived peptide.•Immunological studies on TUBO cancer cell line and mice bearing HER2+ breast cancer.•Prophylactic and therapeutic studies on mice bearing HER2+ breast cancer.

This study was designed to prepare and characterize nanoliposomal vaccine formulation encapsulating AE36 HER2/neu-derived peptide with or without CpG and evaluate the immunologic and therapeutic responses of that in BALB/c mice model of Her2 overexpressing breast cancer. AE36 was encapsulated in liposomes composed of DOTAP, DOPE and Cholesterol (DDC) or DD with. The formulations could induce both CD8+ and CD4+ responses and stimulate production of cytokines which was detected by Enzyme-linked immunospot assay (ELISpot) kits, cytotoxicity test and intracellular cytokine assay by flow cytometry. The formulation showed both therapeutic and prophylactic effects in BALB/c mice bearing Her2+ breast cancer. DDC + CpG showed the best effect in prophylactic study and DD + pG showed the best effect in therapeutic study, which both of them decreased the size of tumors significantly. The engineered nanoliposomes containing AE36 could be a candidate vaccine for the treatment or prophylaxis of HER2+ breast cancer and merits further investigation.