Different cell sensitivity to pulsed electric field

Abstract

One of the most anticipated benefits of medical applications of electric pulses (EP) in cancer therapy is their potential to selectively ablate tumors while sparing healthy tissues. The reason for such selectivity is the differential sensitivity of diverse cells and tissues to killing by EP. Early studies observed profound differences in sensitivity of various tumor and normal cell lines when exposed to either 100 or 10 μs pulses. The recent studies using short EP with pulse durations ranging from 10 to 300 ns have also reported a differential sensitivity of various cell lines. Although nanosecond EP applications require more energy to kill the cells, they provide a more distinct separation in cell sensitivities than conventional longer pulses thus demonstrating the better potential for selective elimination of the cell lines and tissues. Life or death decisions in response to EP exposure depend on many processes determining an ability of the cell to reseal the plasma membrane instantly after EP treatment and ability of the resealed cells to recover from EP insult. The mediators regulating cell sensitivity to EP are under investigation, and the role of some of them (lipid content, actin cortex) will be discussed in this chapter. While the data indicate a potential of EP for selective elimination of certain types of cells, there are no clear criteria for prediction of cell sensitivity to EP. Effect of electric pulses in cells partially can be predicted on the bases of presently known parameters but requires experimental verification on specific sets of cell lines and EP parameters (pulse duration, amplitude, frequency of their delivery).