Effect of Low-Field High-Frequency nsPEFs on the Biological Behaviors of Human A375 Melanoma Cells

Objective: To evaluate the effect of low-field high-frequency nanosecond pulsed electric fields (nsPEFs) on multiple biological behaviors of human A375 melanoma cells and to optimize suitable parameters for further study and clinical use. Methods: An nsPEF generator was developed to generate appropriate pulses. Cell apoptosis and the cell cycle were evaluated by flow cytometry. The CCK-8 assay was performed to explore the effect of nsPEFs on the viability of A375 melanoma cells. Cell migration was assessed using a Transwell Boyden Chamber. The proliferation of A375 melanoma cells was determined by the cloning efficacy test. Furthermore, the nude mouse tumorigenicity assay was used to detect the effectiveness of nsPEFs in vivo. Results: The nsPEFs with our tested parameters failed to induce apoptosis of A375 melanoma cells, though nsPEFs with high pulse duration (500 ns) induced necrosis. However, the viability and migration of A375 melanoma cells were significantly inhibited by nsPEFs. nsPEFs also suppressed the proliferation of A375 melanoma cells by restricting cells in G0/G1 phase. Moreover, animal experiments demonstrated that nsPEFs inhibited the growth of melanoma in vivo. Conclusion: Low-field high-frequency nsPEFs failed to induce apoptosis but effectively inhibited the growth of melanoma via affecting other biological behaviors of melanoma cells, such as cell viability, proliferation, and migration. Significance: This study investigated the influence of low-field high-frequency nsPEFs on melanoma through evaluating their effects on multiple biological behaviors and is helpful in the treatment of melanoma and other tumors.