In the context of tumor EVs, we showed that TLR9 agonist-conjugated EVs could dramatically improve the activation of DCs, processing and presentation of EV-encased antigens by DCs, and subsequent priming of antigen-specific CD8+ T cells, leading to significantly improved CTL response and antitumor efficacy against lymphoma and melanoma. The gene discussed is TLR9; the disease is melanoma.