Navigation Links
Total darkness at night is key to success of breast cancer therapy -- Tulane study
Date:7/24/2014

Exposure to light at night, which shuts off nighttime production of the hormone melatonin, renders breast cancer completely resistant to tamoxifen, a widely used breast cancer drug, says a new study by Tulane University School of Medicine cancer researchers. The study, "Circadian and Melatonin Disruption by Exposure to Light at Night Drives Intrinsic Resistance to Tamoxifen Therapy in Breast Cancer," published in the journal Cancer Research, is the first to show that melatonin is vital to the success of tamoxifen in treating breast cancer.

Principal investigators and co-leaders of Tulane's Circadian Cancer Biology Group, Steven Hill and David Blask, along with team members Robert Dauchy and Shulin Xiang, investigated the role of melatonin on the effectiveness of tamoxifen in combating human breast cancer cells implanted in rats.

"In the first phase of the study, we kept animals in a daily light/dark cycle of 12 hours of light followed by 12 hours of total darkness (melatonin is elevated during the dark phase) for several weeks," says Hill. "In the second study, we exposed them to the same daily light/dark cycle; however, during the 12 hour dark phase, animals were exposed to extremely dim light at night (melatonin levels are suppressed), roughly equivalent to faint light coming under a door."

Melatonin by itself delayed the formation of tumors and significantly slowed their growth but tamoxifen caused a dramatic regression of tumors in animals with either high nighttime levels of melatonin during complete darkness or those receiving melatonin supplementation during dim light at night exposure.

These findings have potentially enormous implications for women being treated with tamoxifen and also regularly exposed to light at night due to sleep problems, working night shifts or exposed to light from computer and TV screens.

"High melatonin levels at night put breast cancer cells to 'sleep' by turning off key growth mechanisms. These cells are vulnerable to tamoxifen. But when the lights are on and melatonin is suppressed, breast cancer cells 'wake up' and ignore tamoxifen," Blask says.

The study could make light at night a new and serious risk factor for developing resistance to tamoxifen and other anticancer drugs and make the use of melatonin in combination with tamoxifen, administered at the optimal time of day or night, standard treatment for breast cancer patients.


'/>"/>

Contact: Arthur Nead
anead@tulane.edu
504-247-1443
Tulane University
Source:Eurekalert  

Related medicine news :

1. NIH scientists take totally tubular journey through brain cells
2. Obesity associated with longer hospital stays, higher costs in total knee replacement patients
3. Patients with metabolic disorder may face higher complication risk following total joint replacement
4. Total hip replacement surgery safe for nonagenarian patients
5. Total Balance Men’s: Review Released for Xtend-Life’s Comprehensive Dietary Supplement for Men
6. Extreme Makeover Home Edition Star John Littlefield Discussed His Experiences on The Show on The Total Education Celebrity Show, a Division of The Simply G Media Network
7. OrthAlign, Inc. Announces Milestone in 13,500th KneeAlign® Total Knee Arthroplasty Case
8. Total Wellness Cleanse Review
9. How This Program Helps People Detox Their Body Naturally – HealthReviewCenter
10. Total Body Cleanse and Detox Tips to Improve Health and Wellness Released by Detox Dieter
11. Total Wellness Cleanse Review Released by Detox Dieter
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Total darkness at night is key to success of breast cancer therapy -- Tulane study
(Date:3/24/2017)... (PRWEB) , ... March 24, 2017 , ... ... Nursing Society (ONS) wanted to create a communications platform that positions them as ... goal, Elliance and ONS reinvented their online publication as an always-on, always-fresh news, ...
(Date:3/24/2017)... ... March 24, 2017 , ... On ... Advanced ERISA Benefit Claims Litigation seminar in Chicago, Illinois. She will present ... majority of cases litigated under ERISA involve claims for long-term disability benefits. ...
(Date:3/24/2017)... ... ... Viewers who like to educate themselves on current issues and who enjoy ... societal issues tend to appreciate and love the "Informed" series, hosted by Rob Lowe. ... for causes around the world. , Running for charity has become a ...
(Date:3/24/2017)... Southlake, Texas (PRWEB) , ... March 24, 2017 ... ... make 2017 the year of enhancements, upgrading their training and leads programs. , ... Empower University. Reserved for elite sales agents, Performance Partners is designed to teach ...
(Date:3/24/2017)... ... March 24, 2017 , ... “Finding ... God #TruthwithGrace”: a devotional journal chronicling the writer’s path toward true communion with ... Walk with God #TruthwithGrace” is the creation of published author Lea Michelle Johnson, ...
Breaking Medicine News(10 mins):
(Date:3/24/2017)... KNOXVILLE, Tenn. , March 23, 2017 /PRNewswire/ ... ("Provectus" or the "Company"), a clinical-stage oncology and ... previously announced Definitive Financing Commitment Term Sheet (the ... with a group of the Company,s stockholders, who ... "PRH Group" in a Form 8-K filed with ...
(Date:3/23/2017)... March 23, 2017 The key factors ... increasing diabetic population, accelerating economic growth and increasing healthcare expenditure. ... are higher life expectancy of ESRD patients, rising demand for ... However, the expansion of the market is hindered by high ... ...
(Date:3/23/2017)... -- As a result of diagnostic technology increasing ... allergic diseases, cutting edge developments in targeted drugs ... in which pharmaceutical and biotech companies are addressing ... both a high quality meeting and a platform ... research scholars and doctors. The event will also ...
Breaking Medicine Technology: