Objective: To investigate the treatment of spontaneous metastatic lung cancer by tumor antigen-pulsed, interleukin-12 (IL-12) gene-modified dendritic cells (DC). Methods:The spontaneous metastatic lung cancer model, prepared by injection of the 3LL Lewis lung cancer cells into the footpads of C57BL/6 mice, was treated by subcutaneous vaccination with tumor antigen peptide mut1-pulsed, IL-12 gene-modified dendritic cells (DC-IL-12/mut1) derived from the normal bone morrow. After treatment, the lung weight, the number of lung metastatic nodes and the survival time of the tumor-bearing mice were observed, and the NK and CTL activity were determined respectively. The mice were divided into 8 groups with 12 mice in each group. Results: Compared with mice treated with mut1-pulsed, control LacZ gene modified DC and untreated DC, tumor-bearing mice treated with DC-IL-12/mut1 had the lightest lung weights (P<0.01), the least lung metastatic node number (P<0.01), the longest survival time (P<0.01), also with the induction of potent CTL activity (P<0.01) and NK activity (P<0.01). Conclusion: Tumor antigen-pulsed, IL-12 gene-modified dendritic cells have significant therapeutic effects on the spontaneous metastatic lung cancer, providing a new approach to treatment of lung tumors.
