Oxidative Effects during Irreversible Electroporation of Melanoma Cells—In Vitro Study

Abstract

Irreversible electroporation (IRE) is today used as an alternative to surgery for the excision of cancer lesions. This study aimed to investigate the oxidative and cytotoxic effects the cells undergo during irreversible electroporation using IRE protocols. To do so, we used IRE-inducing pulsed electric fields (PEFs) (eight pulses of 0.1 ms duration and 2–4 kV/cm intensity) and compared their effects to those of PEFs of intensities below the electroporation threshold (eight pulses, 0.1 ms, 0.2–0.4 kV/cm) and the PEFs involving elongated pulses (eight pulses, 10 ms, 0.2–0.4 kV/cm). Next, to follow the morphology of the melanoma cell membranes after treatment with the PEFs, we analyzed the permeability and integrity of their membranes and analyzed the radical oxygen species (ROS) bursts and the membrane lipids’ oxidation. Our data showed that IRE-induced high cytotoxic effect is associated both with irreversible cell membrane disruption and ROS-associated oxidation, which is occurrent also in the low electric field range. It was shown that the viability of melanoma cells characterized by similar ROS content and lipid membrane oxidation after PEF treatment depends on the integrity of the membrane system. Namely, when the effects of the PEF on the membrane are reversible, aside from the high level of ROS and membrane oxidation, the cell does not undergo cell death.

Micro- and Nanosecond Pulses Used in Doxorubicin Electrochemotherapy in Human Breast and Colon Cancer Cells with Drug Resistance

“…The application of PEFs contributes to the reversible or irreversible lipid membrane reorganization [ 18 ] and changes in MDR pumps’ activity. This effect also induces oxidative stress, which depends on the PEF’s parameters [ 33 , 34 ]. These factors contribute to a better cytostatic activity, which can enter the cell and lipid membrane, and MDR proteins are not a barrier.…”

Effects of high-frequency nanosecond pulses on prostate cancer cells

“…Cell viability and caspase 3/7 activity assays. After permeabilization, the viability of cells was measured in 24 h with MTT assay 26 . We utilized a Caspase-Glo 3/7 Assay from Promega (Madison, WI,) to assess the caspase 3/7 activity in 8 h 27 .…”

ROS Pleiotropy in Melanoma and Local Therapy with Physical Modalities

“…ROS production is a byproduct of the pulsed electric field treatment and plays a role in its efficacy [ 192 ] as it can be prevented by antioxidants [ 193 , 194 ]. ROS production and oxidative stress were also observed in electroporated melanoma cells in vitro [ 195 ]. Novel ECT approaches involve calcium electroporation with promising clinical results [ 196 ].…”