Enhancing the treatment effects of tumor cell purified autogenous heat shock protein 70-peptide complexes on HER-3-overexpressing breast cancer*

Abstract

Abstract Objective The aim of this study was to enhance the treatment effect of tumor purified autogenous heat shock protein 70-peptide complexes (HSP70-PCs) on HER-3-overexpressing breast cancer. Methods In this study, we first studied the expression of HER-3 in breast cancer tissues and its relationship with patient characteristics. We then purified HSP70-PCs from primary breast cancer cells with different HER-2 and HER-3 expression profiles and determined the cytotoxicity of autogenous dendritic cells (DCs) and CD8+ T cells induced by these complexes. Third, recombinant human HSP70-HER-3 protein complexes were used to inhibit the autogenous HSP70-PCs purified from HER-3-overexpressing breast cancer cells, and the resulting immunological response was examined. Results The results show that HSP70-PCs can be combined with recombinant HSP70-HER-3 protein complexes to induce stronger immunological responses than autogenous HSP70-PCs alone and that these treatments induce autogenous CD8+ T cell killing of HER-3-positive breast cancer cells. Conclusion These findings provide a new direction for HSP70-DC-based immunotherapy for patients with HER-3-overexpressing breast cancer.