Combination of Radiofrequency Ablation and Glycated Chitosan as Treatment on a Syngeneic Breast Tumor Model.

Aim: Effects of radiofrequency ablation (RFA) combining immunoadjuvant glycated chitosan (GC) on tumor control and potent cytokine responses were investigated in a syngeneic breast tumor model. Materials and Methods: Murine 4T1 breast carcinoma cells harboring the luciferase reporter gene were used to evaluate the tumor growth rate and metastasis in vivo using bioluminescent imaging. Plasma of RFA/GC-treated tumor-bearing mice was collected for ex vivo cytotoxicity analysis and mouse chemokine array assays. Results: Tumor growth and systemic metastasis were suppressed by combined RFA and GC when tumor size reached 300 mm(3), not detected, however, when tumor size reached 800 mm(3). The survival rate of mice bearing small tumors was also higher than that of large ones after RFA-GC treatment. Plasma extracted from RFA-GC-treated small tumor-bearing mice exhibited cytotoxicity on cultured 4T1 cells. Moreover, reduced tumor growth-related cytokines and increased antitumor-related cytokines were detected in the plasma collected. Conclusion: RFA combining GC could control tumor progression with induced potent antitumor cytokine responses.