Melatonin is found in animals as well as plants. In animals, it is a hormone that anticipates the daily onset of darkness and regulates physiological functions, such as sleep timing, blood pressure, and reproduction. Melatonin has also been found to have anti-tumor properties. Malignant cancers are the most common cause of death, and the mortality rate of ovarian tumor is the highest among gynecological diseases. This study investigated the anti-tumor effects of melatonin on the ovarian cancer lines, OVCAR-429 and PA-1. We observed the accumulation of melatonin-treated cells in the G1 phase due to the down-regulation of CDK 2 and 4. Our results suggest that in addition to the known effects on prevention, melatonin may also provide anti-tumor activity in established ovarian cancer.
Shen, C. J., Chang, C. C., Chen, Y. T., Lai, C. S., & Hsu, Y. C. (2016). Melatonin suppresses the growth of ovarian cancer cell lines (OVCAR-429 and PA-1) and potentiates the effect of G1 arrest by targeting CDKs. International Journal of Molecular Sciences, 17(2). https://doi.org/10.3390/ijms17020176