A dual-acting compound that fights—or could prevent—breast cancer, developed by pharmacy professors Dr. Paula Witt-Enderby and Dr. David Lapinsky and former professor Dr. Vicki L. Davis, has been patented.
Their design incorporates melatonin, a naturally occurring hormone associated with the sleep-wake cycle, and tamoxifen, a medication often used to treat and prevent certain types of breast cancer. Individually, the two substances target breast cancer differently. In combination, their positive impact seems intensified. Additionally, the compound could be even more important because of a new discovery that exposure to even dim light at night can cause cancer cells to grow faster.
“Individually, melatonin and tamoxifen can tackle breast cancer in different ways, so the idea is that if they were appropriately combined into a single medicine, they could potentially synergistically treat or prevent breast cancer by a number of different mechanisms,” said Lapinsky, associate professor of medicinal chemistry.
“The data show enhanced binding, a very unique result, in terms of how well the melatonin-tamoxifen hybrid compound binds to their individual receptors,” said Witt-Enderby, professor of pharmacology and a melatonin specialist.
The ramped-up impact from delivering both in a single compound hints that a special association between estrogen and melatonin receptors occurs in the presence of this new hybrid drug that could prove to be protective against breast cancer; however, this still needs to be confirmed through rigorous testing.
“While tamoxifen carries an increased risk of endometrial cancer, this unwanted side effect could be offset by the new compound because, in data to be published, melatonin has been shown to protect the uterus from excessive estrogen stimulation,” said Witt-Enderby.
Additionally, new findings from the Tulane University of School of Medicine show that exposure to even a low level of light spurs cancer cells growth, according to The Scientist Magazine.
“The patent is so important because of this research from Tulane, showing that dim light equivalent to the light seen from under the door in an otherwise dark room is enough to increase tumor cells because melatonin is suppressed—and not only does cancer then grow faster, it also becomes tamoxifen resistant,” Witt-Enderby said.
Other studies have pointed to melatonin as inhibiting pathways for cancer growth and progression, and as a natural anti-depressant. Depression may occur alongside cancer.
“There’s just a wealth of background information that logically says tamoxifen and melatonin should be combined together for purposes of either the treatment or prevention of breast cancer,” Lapinsky said.
The multifaceted approach to fighting cancer is a trend in drug development. “We used to think we should only develop one drug to hit one drug target, but cancer cells are just so darn smart they’ll figure out a way to create resistance affecting that one drug target or one drug,” Lapinsky said. “So researchers have changed to the perspective that we need to hit cancer in multiple ways to achieve effective treatment and prevention.”