Epitope diversification driven by non-tumor epitope-specific Th1 and Th17 mediates potent antitumor reactivity

► Non tumor-specific CD4+ T cells can induce tumor antigen presentation by DC. ► Th1 and Th17, but not Th2 facilitated diverse tumor antigen presentation. ► Autocrine of IL-23 by DC plays a critical role in diverse tumor antigen presentation. ► Diverse tumor antigen presentation resulted in potent antitumor immunity in vivo.