Abstract
INTRODUCTION: Colorectal cancer (CRC) is one of the most prevalent malignancies worldwide. Tumor Treating Fields (TTFields), a novel anticancer therapy using intermediate frequency and low-intensity alternating electric fields, has demonstrated efficacy in various cancers, but its application in CRC remains underexplored. OBJECTIVE: To determine the optimal frequency and treatment duration of TTFields therapy for CRC through in vitro experiments. METHODS: Four human CRC cell lines (2 MSI: HROC110 T1 M7, HROC285 T0 M2; 2 MSS: HROC450, HROC463) were treated using the inovitro TTFields system. Frequencies (100, 200, 300 kHz) and daily exposure durations (16, 20, 24 h/day) were varied. Cell viability was assessed after 72 h using crystal violet staining and spectrophotometry. Data were analyzed using t-tests or ANOVA, with p < 0.05 considered statistically significant. RESULTS: TTFields significantly reduced cell viability at all tested frequencies. The 100 kHz frequency yielded the most pronounced effects, especially in MSI cell lines (p < 0.001). Treatment duration of 24 h/day led to the greatest viability reduction across all cell lines (p < 0.01), while 16 h/day and 20 h/day showed comparatively weaker effects. CONCLUSION: Our study demonstrates that TTFields effectively reduce CRC cell viability, supporting their therapeutic potential. Further studies are needed to understand their mechanisms and synergy with existing treatments.