Effect of irreversible electroporation on cancer cells

Cancer remains responsible for several million deaths each year, occurring worldwide. The conventional treatment strategies for cancer cause a plethora of side effects along with an exorbitant treatment cost per sitting. The focus now is on the development of new modalities of treatments which could minimize the side effects and prove to be an affordable treatment option to the patients. Usage of electrical pulses along with drugs - Electrochemotherapy (ECT) is a fast rising option for the treatment of chemo-refractive cancers. This has proven to be more efficient and effective than other existing methods of treatment and there is a growing evidence of research and clinical trials on the same. The major advantage that this mode of treatment offers is the massive reduction in the dosage of drug that is administered, thus significantly reducing the intensity of undesired side effects. The applied electrical pulses can be of two types - that for reversible and irreversible electroporation of cells. While reversible electroporation is primarily used as a means for delivery of molecules into the cell, irreversible electroporation is a mode which could be applied as such in the absence of a chemodrug to kill the cancerous cells. This would be of immense significance in the clinical scenario since it could be targeted treatment while totally eliminating the necessity of any chemodrug. In this paper we give a detailed report on the effect of such high voltage pulses on cancer cells. The variables tested out in the pulse parameters used include intensity of electric field applied, pulse duration, number of pulses and time interval between each train. The electric field applied is varied between 500V/cm to 2500V/cm with a pulse duration ranging from microseconds to milliseconds to keep the energy delivery constant. The effect of the parameters individually and effect of combination of all these parameters on the cells is studied and discussed in this paper. This study could be of clinical relevance in the translation of these findings to application at the patient-level.