FLICKR, JO NAYLORExposure to even a low level of light at night makes implanted human breast cancer tumors grow faster in rats and makes the cancer cells impervious to the drug tamoxifen, according to a study published today (July 25) in Cancer Research. The researchers attributed these effects to light’s suppression of melatonin production, and showed that administering melatonin in the rodents’ drinking water helped eliminate the negative effects of light exposure.
“The implication is that it may be possible to overcome the insensitivity of some tumors in cancer patients by giving supplemental melatonin,” Russel Reiter, a professor of cell biology at the University of Texas Health Science Center in San Antonio who was not involved in the study, wrote in an e-mail to The Scientist. He added that the idea should be tested in clinical trials “as soon as possible.”
“I think it’s pretty much consistent with our growing knowledge that lifestyle is an enormous influence on breast cancer,” said Pamela Munster, a professor of medicine at the University of California, San Francisco, who also was not involved with the study.
Exposure to light at night in humans has been linked epidemiologically to many cancers, including ...
