Efficient apoptosis via double-strand breaks of DNA in human epithelial cells induced by non-thermal effect of high-field broadband terahertz waves.

Induction of apoptosis is a primary strategy in cancer therapies in clinical oncology. Chemical or biological stimuli generally result in drug or agent resistance and damage to the immune system. Current physical stimuli have strong side effects, such as radiation injury or collateral thermal damage, due to the inflammation from the necrosis. Therefore, a new physical non-inflammatory therapy based on a non-thermal effect is highly desirable. Here, we report highly efficient apoptosis, reaching nearly 99% in breast cancer cells, one of the human epithelial cells, induced by the non-thermal effect of high-field (average field strength of ~ 5.87 MV/cm) broadband terahertz (THz) waves via double-strand breaks of DNA damage after 4 h of irradiation. This is accompanied by 11 highly differentially expressed genes related to apoptosis and significant morphological changes in the cells. These results suggest that the non-thermal effect of high-field broadband THz waves could be used to develop a potential novel, noninvasive, and non-inflammatory therapy for human superficial tumors.