PRF1 and neoplasm: It was demonstrated in almost all the studies under consideration thatadministration of DC-based vaccines activates an antitumor immune response:tumor-specific cytotoxic CD8+ T cells are activated; perforin andgranzyme expression and IFN-γ production are enhanced; some patientsdevelop a hypersensitivity response to tumor antigens (the DTH response); theregulatory T-cell count decreases, etc. However, despite the substantial immuneresponse, the clinical efficacy of antitumor DC-based therapy is lessimpressive.