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 mm³, not detected, however, when tumor size reached 800 mm³. 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.