| Backgroud:Cryoablation is becoming the primary therapy for liver metastasis from colorectal cancer, while the exploration of cryoimmunology response will provide the combination of local therapy with immune therapy, and would provide rationale and experimental foundation for synthetic therapy of advanced cancer. Objective:To make the models of liver metastasis from colorectal cancer. To assess the anti-tumor immune response after cryoablation combined GM-CSF treatment. Material andMethods:Mouse models of liver metastasis from colorectal cancer were made, and the tumor-bearing mice were divided into different groups:control group, GM-CSF group, cryoablation group, cryoablation+GM-CSF group. Cryoablation was applied by cryosurgery needle with1.7mm diameter from Endocare Argon-Helium cryosurgery system. Tumor size and survival time were observed, the number changes of dendritic cells in tumor were assessed by immunohistochemistry, serum cytokine (IFN-y, IL-4) levels were analyzed by enzyme-linked immunosorbent assay (ELISA), and the Thl/Th2ratio was estimated from the IFN-y/IL-4ratio.Result:(1) The Cryoablation+GM-CSF treatment significantly reduced to tumor lesion size (P＜0.001), and to extend the survival time of tumor-bearing mice (p＜0.001).(2) On the day before, seventh day after,14th day after,21st day after cryoablation+GM-CSF treatment, the DC numbers per high power field in tumor were1.5±0.55,17.4±1.26,14.6±0.54,7.2±1.47respectively (P＜0.05).(3) The Thl/Th2ratios were6.32±0.45,13.43±0.23,14.87±0.53,15.54±0.64on the day before, seventh days after,14th day after,21st day after cryoablation+GM-CSF treatment (P＜0.05). Conclusion:Combined cryoablation with GM-CSF treatment could increase the number of DC in tumor micro environment, improve the systemic anti-tumor immune response, increase the ratio of Thl/Th2, prolong the median survival times. |
