Low electric field parameters required to induce death of cancer cells

Abstract

Irreversible electroporation (IRE) is a novel technique that deals with killing undesirable cells, mainly cancer cells, directly without using any cytotoxic drugs. Commonly in this technique very high electric field up to 1000 V/cm is used but for very short exposure time (nanoseconds). Low electric fields (LEFs) are used before to internalize molecules and drugs inside the cells (electroendocytosis) but mainly not in killing the cells. The aim of this work is to determine the ability of using LEFs to kill cancer cells (Hela cells). The Physics idea is in making LEFs energy equivalent to IRE energy. Four IRE protocols were selected to represent very high, high, moderate and mild voltages IRE, then we make equivalent energy for each of these protocols using different LEFs’ parameters of different amplitudes (7, 10, 14 and 20 V), different pulse numbers (40, 80, 160 and 320 pulses), different frequencies from 0.5 to 106.86 Hz and different pulse widths from 9.38 to 2000 ms. Each of the calculated LEF equivalent to IRE was applied on Hela cell line. The results show complete destruction of the cancer cells for all the tested exposure protocols. This damage was not due to thermal effect because the measured temperature was not changed before and after the exposure. The possible effect mechanism is discussed. It was concluded that the lethal effect on the cancer cells can be achieved using LEFs if the same energy equivalent to IRE is used. This work will help in using low-risk drug-free techniques in cancer treatment.