Effect of Cold Atmospheric Plasma on Gene Expression and Methylation of Genes Involved in Colorectal Cancer

Background and purpose: Colorectal cancer (CRC) is ranked as the second most common cancer in men and the third most common cancer in women worldwide. Routine treatments have many side effects and little efficiency. The aim of this study was to investigate the effects of Cold Atmospheric Plasma (CAP) on epigenetic changes of some genes involved in CRC progression. Materials and methods: Proliferation rate of cells after 40 s treatment was analyzed using MTT assay. Gene expressions of Beclin-1, Runx3, and AIM2 were measured using Real time PCR and methylation alternations of mentioned genes were evaluated with quantitative Methylation-Specific PCR (Q-MSP). Results: The viability of CAP-treated C26 cells significantly decreased compared to that of the L929 cells. The viability of C26 cell line decreased to75%, 52.2%, and 34% following 12, 24, and 48 hours of CAP therapy for 40 seconds. CAP therapy decreased the AIM2 expression (fold change=0.12) and increased the Runx3 gene expression (fold change=2.66) in C26 cell line. Also, treatment with CAP decreased the methylation level of Runx3 gene in CAP-treated cells compared with untreated cells (33.45% vs 63.24%). Conclusion: This study confirmed the selective effect of CAP on cancer cells which is an ultimate goal of cancer therapy approach. Also, CAP treatment was found to affect gene expression and methylation level of critical players of CRC.