Light-at-night (LAN) is a worldwide problem co-distributed with breast cancer prevalence. We hypothesized that exposure to LAN is coincided with a decreased melatonin (MLT) secretion level, followed by epigenetic modifications and resulted in higher breast cancer tumors growth-rate. Accordingly, we studied the effect of LAN exposure and exogenous MLT on breast cancer tumors growth-rate. 4T1 cells were inoculated into BALB/c short day-acclimated mice, resulting in tumors growth. Growth rates were followed under various light exposures and global DNA methylations were measured. Results demonstrated the positive effect of LAN on tumors growth-rate, reversed by MLT through global DNA methylation.
Bibliographical noteFunding Information:
The authors declare no conflict of interests. Authors are thankful to the Research Authority, the University of Haifa, for their partial financial support.
- Breast cancer
- Epigenetic modifications
- Global methylation state
- Light at night
ASJC Scopus subject areas
- Physiology (medical)