Preclinical Study of Locoregional Therapy of Hepatocellular Carcinoma by Bioelectric Ablation with Microsecond Pulsed Electric Fields (µsPEFs).

Unresectable hepatocellular carcinoma (HCC) needs locoregional ablation as a curative or downstage therapy. Microsecond Pulsed Electric Fields (µsPEFs) is an option. A xenograft tumor model was set up on 48 nude mice by injecting human hepatocellular carcinoma Hep3B cells subcutaneously. The tumor-bearing mice were randomly divided into 3 groups: µsPEFs treated, sham and control group. µsPEFs group was treated by µsPEFs twice in 5 days. Tumor volume, survival, pathology, mitochondria function and cytokines were followed up. µsPEFs was also conducted on 3 swine to determine impact on organ functions. The tumors treated by µsPEFs were completely eradicated while tumors in control and sham groups grew up to 2 cm(3) in 3 weeks. The µsPEFs-treated group indicated mitochondrial damage and tumor necrosis as shown in JC-1 test, flow cytometry, H&E staining and TEM. µsPEFs activates CD56+ and CD68+ cells and inhibits tumor proliferating cell nuclear antigen. µsPEFs inhibits HCC growth in the nude mice by causing mitochondria damage, tumor necrosis and non-specific inflammation. µsPEFs treats porcine livers without damaging vital organs. µsPEFs is a feasible minimally invasive locoregional ablation option.