Objective To explore in vitro cytotoxic activities of DCIKs against hepatocarcinoma cells by co-culturing cytokine-induced killer cells (CIKs) with dendritic cells (DCs) derived from peripheral blood of patients with hepatocellular carcinoma (HCC).Methods Peripheral blood mononuclear cells (PBMCs) were isolated from 23 patients with HCC and cultured with cytokines to induce DCs and CIKs.DCIKs were induced by co-culturing CIKs with DCs.After 14 days of co-culture,the phenotypes of DCIKs and CIKs were analyzed by flow cytometry,and their in vitro cytotoxic activities against SMCC-7721 and HepG2 hepatocarcinoma cells were measured by MTT assay.Levels of IL-12,IL-4 and IFN-γ in the supernatants of cell culture were detected by enzyme-linked immunosorbent assay (ELISA).Results High expressions of CD3+CD8+ and CD3+CD56+ were observed on DCIKs.The percentages of effector cells,cytotoxic activity and cytokine secretion were all significantly increased with DCIKs as compared with those CIKs without DC co-culture (P＜0.05).Conclusion Co-culture of CIKs with DCs can enhance the differentiation of effector cells and the cytolytic activities of CIKs against hepatocarcinoma cells in vitro.Immunotherapy with DCIKs may be a promising strategy for the treatment of patients with HCC.