P-208 - The Therapeutic Effect of Irreversible Electroporation Ablation in Colon Cancer Animal Model

Date 04 July 2015
Event WorldGI 2015
Session Posters
Topics Basic Science
Colon Cancer
Surgery and/or Radiotherapy of Cancer
Presenter H.S. Choi
Citation Annals of Oncology (2015) 26 (suppl_4): 1-100. 10.1093/annonc/mdv233
Authors H.S. Choi1, H.J. Chun1, I.K. Yoo1, J.M. Lee1, S.H. Kim1, E.S. Kim1, B. Keum1, Y.T. Jeen2, H.S. Lee1, C.D. Kim1
  • 1Korea University College of Medicine, Seoul/KR
  • 2Department of Internal Medicine, Seoul/KR

Abstract

Introduction

Irreversible electroporation (IRE) is a promising novel technique for the ablation of tumors. IRE has an advantage over other ablation technique in its mechanism to remove undesired cells by affecting the cell membrane without thermally destructing blood vessels, nerves and the surrounding tissues. Studies regarding the clinical application of IRE have been performed in humans, as well as in animals, for organs such as the liver, kidney, prostate, etc. and IRE is now accepted as a novel anti-cancer ablation modality. The aim of this study was to evaluate the therapeutic effect of IRE in colon cancer animal model for the first time.

Methods

The Caco2 cells (ATCC) were cultured in petri-dishes. Male nude mice (Immunodeficient (CAnN.Cg-Foxn1 nu/CrljBgi) 6 weeks old, Orient inc., Korea) were introduced. Caco2 cells were each visually injected at 1.0 x 107 cells/ml into both flakes (one for control, the other for IRE). We performed in vivo IRE procedures in the tumors of nude mouse model. Electrical pulses were applied to the tumor of nude mouse using a DC generator at 1 ∼ 2kV/cm amplitude, 20 ∼ 50 pulses, 100 µS length, with 1mm separation between two needle type electrodes. We analyzed the tissues with H&E staining and TUNEL assay immediately afterwards, and then 10 hours, 24 hours.

Results

All mice were preserved during the experiment without significant complications. There was complete cell death within the IRE lesions without intervening live cells. Variable nucleic changes-pyknosis and karyohexis, and vacuolar degeneration were observed only within the IRE lesions. The framework of extracellular matrix and blood vessels were not affected by IRE. The apoptotic area and signals were increased in IRE groups comparing control groups in tunnel assay.

Conclusion

The present study demonstrated that IRE ablated colon cancer tissue very effectively through the induction of cellular apoptosis. This study suggests that IRE is the potential use of IRE in gastrointestinal cancer.