Abstract 2370: Therapeutic nano-DC vaccine For HER2 positive breast cancer

Abstract

Abstract Harnessing a patient's own immune capacity to eradicate malignant cells is a promising approach for cancer treatment, and therapeutic vaccine represents an important arm of cancer immunotherapy. Our research aims to develop a potent therapeutic cancer vaccine for breast cancer which is traditionally considered as poorly immunogenic. We have recently shown that porous silicon microparticles (PSMs) can stimulate type I interferon (IFN) expression in dendritic cells (DCs), and thus serve as a potent adjuvant for a therapeutic cancer vaccine (Xia et al: Cell Reports 2015, 11:957-966). This action is mediated by the TRIF/MAVS pathways, and is independent of the cell surface or endosomal Toll-like receptors. In addition, the nanometer-size pores in PSMs can serve as a reservoir for sustained antigen release. We have assembled a Nano-DC vaccine comprising of bone marrow-derived DCs internalized with HER2 antigen peptide-loaded PSMs. Treatment of murine models of HER2 positive breast cancer with this Nano-DC vaccine not only activates and expands antigen-specific CD8+ T cells, but also promotes a Th2-to-Th1 transition in the tumor microenvironment to favor anti-tumor activity. Thus, our result supports the development of a therapeutic Nano-DC vaccine for breast cancer. Citation Format: Haifa Shen, Xiaojun Xia. Therapeutic nano-DC vaccine For HER2 positive breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2370.