Comparative study of Nano knife, cryoablation, radiofrequency ablation in the muscle xenografts in rabbits

Abstract

Objective To investigate the apoptosis, immunity and angiogenesis factor changes of rabbits after irreversible electroporation (IRE), cryoablation, radiofrequency ablation (RFA) of muscle can-cer xenografts, and to observe the antitumor effect and security of diversiform minimally invasive tech-niques for muscle cancer xenografts. Methods Eight muscle cancer xenograft models were randomly di-vided into IRE, cryoablation, RFA and control group, each group contained 2 rabbits. All the rabbits were executed after 24 hours. Liver, kidney function and creatinekinase were tested. ELISA methods were used to detect CTnI, Caspase-3, TNF-α and VEGF levels in the plasma. Tunel assay was used to detect the apoptosis of tumor tissue. Immunohistochemistry was applied to detect Bcl-2, HSP70 and VEGF expres-sion in muscle cancer xenografts. Results Rich blood vessels were showed on the tumor surface, with soft texture. Obvious coagulation necrosis and edema were found in the adjacent muscle tissue. HE stain-ing showed a clear borderline between the necrotic and normal area in the IRE group, visible liver cells in the cryoablation and RFA group. Tunel assay showed that IRE can significantly increase the apoptosis in muscle cancer cells compared with other groups. Each group could promote tumor apoptosis by increasing plasma Caspase-3 level and reducing Bcl-2 expression in the treatment area, inspired the antitumor im-munity by elevating plasma TNF-α level and induced to the elevation of plasma VEGF secretion in the short time after treatment, HSP70 and VEGF factor expression were variant in edge of the treatment area. Post-treatment serological test showed that liver, kidney functions and CTnI were within the normal range, except for significant higher levels of creatine kinase. Conclusions IRE, cryoablation, and RFA can in-hibit the growth of liver tumors via ablating directly, inducing apoptosis, producing specific anti-tumor im-mune response, it is safe and effective. IRE has advantages in the induction of apoptosis, protection of im-portant viscera nearby and short ablation time. This study may support further clinical application of IRE on human beings with the evidence from animals. Key words: Neoplasm transplantation; Models, animal; Muscle; Irreversible electroporation; Ab-lation techniques; Apoptosis