Fig. 1.

TTFields kill cancer cells by triggering apoptosis followed by extracellular release of HMGB1. LLC-1 and murine CT-26 colon carcinoma cells were treated with TTFields for 24–72 h at optimal frequency. a Effect of TTFields treatment on cell counts. N ≥ 3, and data are presented as mean ± SD. b Elevation of percentage of early apoptotic cells (Annexin V +/7AAD-) and late apoptotic cells (Annexin V+/7AAD+) following treatment with TTFields. N ≥ 3. c Release of HMGB1 was monitored using ELISA assay. N ≥ 3, and data are presented as mean ± SD. P values were determined using one-way ANOVA followed by Dunnett’s post-test. *P < 0.05; **P < 0.01; ***P < 0.001