ABSTRACT
Objective To investigate the therapeutic effects of microwave ablation combined with dendritic cell (DC) tumor vaccine on a murine breast cancer model and to explore its immunological mechanism.Methods Forty-eight Balb/c mice were used to establish models of mouse mammary carcinoma,and then randomly divided into a sham-operation group,a microwave ablation treated group,a DC tumor vaccinated group and a microwave ablation plus DC tumor vaccinated group.Microwave ablation was conducted with the microwave ablation group on day 14 after establishing the model.DC tumor vaccination was performed on day 7 in the vaccinated group.In the microwave ablation plus DC tumor vaccinated group,DC tumor vaccination and microwave ablation were consecutively performed on days 7 and 14,respectively.Tumor growth,lung metastasis and survival were observed.The proportion of CD3+ and CD4+ T cells in splenocytes were analyzed by fluorescence Activated Cell Sorter (FACS) on the 14th day after microwave ablation.Serum levels of interferon-γ (IFN-γ) and interleukin-4 (IL-4) were also detected using ELISA.Results The survival time (56.4 ± 4.3 days),tumor size (67.3 ± 6.1 mm2) and lung metastasis index (0.6 ± 0.4) in the microwave ablation plus DC tumor vaccinated group were all significantly lower than the corresponding averages in the microwave ablation and DC tumor vaccinated group.The proportions of splenic CD3 + T cells (27.8 ±10.3 ％) and CD4+ T cells (16.7 ± 8.3 ％) in the microwave ablation plus DC tumor vaccinated group were significantly larger than in the control group.Average serum levels of IFN-γ (41.8 ± 22.9 pg/ml) in the microwave ablation plus DC tumor vaccinated group were also significantly larger than in the control group,while the average serum level of IL-4 (15.4± 6.4 pg/ml) was significantly lower.Conclusions Microwave ablation and DC tumor vaccination together could have synergistic effects in treating experimental breast cancer,which might be closely related to the enhanced immune response.
