The result showed that X-ray irradiation (IR, inducing DNA double-strand breaks25), ultraviolet (UV, inducing DNA single-strand breaks25), and nine DNA-damaging drugs significantly increased KIFC1 and γH2AX (a DNA damage marker26) expressions in human breast cancer MDA-MB-231 cells (Fig. 2b). The gene discussed is KIFC1; the disease is breast cancer.