TLR7 and breast cancer: Immune adjuvant effects through TLR3 and TLR7 can be achieved with systemic administration of poly(A:U); TLR3 is required to generate IFN-γ–producing CD8+ T cells, and TLR3 and TLR7 are required for clonal expansion of antigen-specific cells [74].The potent adjuvant activity of poly(A:U) has been exploited in breast cancer cells [75].