Alterations in the mortality and growth cycle of cervical cancer cells treated with electroporation at different electric strengths

Objective: To explore the biological effects of electric fields of various strengths on Hela cells. Methods: Electroporation experiments were performed using Hela cells. Changes in cell mortality, cell vitality, cell cycle, and apoptosis status were examined. In addition, temperature changes in the surrounding tissue were measured. Results: Cell proliferation was markedly inhibited after treatment with field strengths of 2-2.5 kV/cm. The expression of caspase-3 increased significantly in cells treated with field strengths of 1.5-2.5 kV/cm. Field strengths of 1.75-2.5 kV/cm produced complete cancer cell ablation. G2 phase frequency increased significantly after treatment with field strengths of 2-2.5 kV/cm. During this process, the maximum temperature increase in the pulsed electric field was 4.9 +/- 1.17 degrees C under free air convection. Conclusions: IRE can be used alone for the treatment of cancer, and its thermal effect is negligible. Cell death was caused by the effects of IRE and apoptosis. The tumor cells must be destroyed completely, or the altered cell cycle may lead to tumor recurrence and accelerated growth.

Pulsed electric field; Cervical cancer cells; Cell cycle; Apoptosis

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