Incorporation of electroendocytosis and nanosecond pulsed electric field in electrochemotherapy of breast cancer cells

ABSTRACT

The study aimed to evaluate the possibility to perform electrochemotherapy using nanosecond pulsed electric field (nsPEF) and low electric field (LEF) monopolar electrical impulses to alleviate the problems of conventional electroporation. Two types of pulses have been used to treat MCF-7 human breast carcinoma cell line: very low voltage (electric field strength) long trains of short unipolar electric pulses, and low frequencies of extremely intense (40kV/cm), ultra-short (10ns) electric pulses. The electropermeabilization efficiency of the formed endocytotic vesicles was measured using the cloning efficacy test. The cell viability was decreased significantly at a repetition frequency begins from 0.01 Hz by ~35% and reached complete cell loss at 1 Hz of nanosecond pulses for cells treated before with monopolar pulses at 20 V/cm in the presence of BLM with 4 µM concentration. The uptake of non-permeant drugs has been done without plasma membrane permeabilization (classical electroporation), but by endocytosis. Nanosecond electric pulses can disrupt the membrane of endocytotic vesicles and release the cytotoxic drug bleomycin.

KEYWORDS:

• Low-electric field (LEF) monopolar pulses
• nanosecond pulsed electric fields (nsPEF)
• cloning efficacy test
• bleomycin (BLM)
• MCF-7 cells

Acknowledgments

The present work was supported by the Department of Radiology and Medical Imaging, College of Applied Medical Sciences, Prince Sattam Bin Abdul-Aziz University, Alkharj, SA.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.