The first evidence regarding the association between miR-200c-3p and radiotherapy resistance came from a study on breast cancer cells in which low levels of miR-200c-3p expression were correlated with radiotolerance, and ectopic miR-200c-3p expression enhanced irradiation-induced apoptosis by directly targeting TBK1 (TANK-binding kinase 1) [24]. The gene discussed is TBK1; the disease is breast cancer.