Relative electropermeability and electric pulse effectiveness in human breast adenoeareinoma: an in vitro study

ABSTRACT

This study was carried out in order to evaluate the effects of electrochemotherapy, electrical pulses and chemotherapeutic drugs on the killing of cancerous cells and their probable synergistic effects. Electrochemotherapy treatments conducted on MCF-7 cell line derived from human breast adenocarcinoma tumor using four chemotherapeutic drugs including bleomycin, cisplatin, adriamycin and cyclophosphamide and six electrical doses. Cell survival assayed using MTT method, 72 hrs after the treatment; also the killing effects of each drug and electric dose determined. Finally, "Relative Pulse Effectiveness" and "Relative Electropermeability Effectiveness" calculated. All electrical doses decreased cell survival, significantly for bleomycin and cisplatin, however, they were only, significant in high concentration of cyclophosphamide and adriamycin. For the applied drugs, "Relative Electropermeability Effectiveness" was more than one [1.00], except for adriamycin. It seems that for the diffusion of molecules into cells, application of high duration electric pulses is more efficient for high molecular weight drugs while for low molecular weight drugs, strong pulses are more effective. In intermediate molecular weight, there is no difference between increasing the pulse strength and/or duration to achieve additional electropermeability. Electropermeability effect of different electric doses and electrochemotherapy efficiency can be evaluated by "REE" and "RPE", respectively