Navigation Links
Connection between light at night and cancer revealed in additional study

A new study from the Center for Interdisciplinary Chronobiological Research at the University of Haifa has found an additional link between Light At Night (LAN) and cancer. This research joins a series of earlier studies carried out at the University of Haifa that also established the correlation. "High power light bulbs contribute more to 'environmental light pollution', which the study has shown is a carcinogenic pollution," notes Prof. Abraham Haim, who headed the study.

Earlier studies in which Prof. Haim has participated at the University of Haifa, have shown that people living in areas that have more night-time illumination are more susceptible to prostate cancer in men and breast cancer in women. The researchers' hypothesis was that LAN harms production of melatonin, a hormone that is released from the pineal gland during the dark part of the 24h cycle and which is linked to the body's cyclical night-day activity and seasonality. When this hormone is suppressed, the occurrence of cancer rises.

The current study, in which Dr. Fuad Fares and Adina Yokler, Orna Harel and Hagit Schwimmer also participated, set out to establish or refute this hypothesis. In order to do so, four groups of lab mice injected with cancerous cells were examined: one group was exposed to "long days" of 16 hours of light and 8 hours of darkness, simulating exposure to artificial light beyond the natural number of light hours in a day; a second group was exposed to the same "long days" but were treated with melatonin; a third group was exposed to "short days" of 8 light hours and 16 dark hours; and a fourth group was exposed to the same "short days" but during the dark hours was exposed to a half-hour interval of light.

The results show once again the clear link between LAN and cancer: the cancerous growths in mice exposed to "short days" were smallest (0.85 cubic cm. average), while those mice exposed to the interval of LAN during dark hours had larger growths (1.84 cubic cm. average) and those exposed to "long days" even larger growths (5.92 cubic cm. average).

The study also discovered that suppression of melatonin definitely influences development of the tumor. The size of tumor in mice exposed to "long days" but treated with melatonin was only 0.62 cubic cm. on average, which is not much different from the size of the growth in mice exposed to "short days". The study also found that the death rate in mice treated with melatonin was significantly lower than in those not treated.

The researchers say that their study results show that suppression of melatonin due to exposure to LAN is linked to the worrying rise in the number of cancer patients over the past few years. However, it is not yet clear what mechanism causes this.

"Exposure to LAN disrupts our biological clock and affects the cyclical rhythm that has developed over hundreds of millions of evolutionary years that were devoid of LAN. Light pollution as an environmental problem is gaining awareness around the world, and the World Health Organization's International Agency for Research on Cancer (IARC) has already classified working the night shift as a higher grade of cancer risk," the researchers noted.


Contact: Rachel Feldman
University of Haifa

Related biology news :

1. Connection between light at night (LAN) and cancer revealed in additional study
2. Brain connections break down as we age
3. Calcium connections: Basic pathway for maintaining cells fuel stores
4. Searching for causes of neural disconnection in schizophrenia
5. Connection elucidated between obesity, salt sensitivity and high blood pressure
6. Brain connections for stress -- lessons from the worm
7. Impaired brain connections traced to schizophrenia mutation
8. Lifelong memories linked to stable nerve connections
9. The food-energy cellular connection revealed
10. Ben-Gurion U. researchers reveal connection between cancer and human evolution
11. MU study finds connection between evolution, classroom learning
Post Your Comments:
(Date:5/12/2016)... , May 12, 2016 , ... published the overview results from the Q1 wave of ... recent wave was consumers, receptivity to a program where ... with a health insurance company. "We were ... share," says Michael LaColla , CEO of Troubadour ...
(Date:5/3/2016)... Lithuania , May 3, 2016  Neurotechnology, ... released the MegaMatcher Automated Biometric Identification System ... of large-scale multi-biometric projects. MegaMatcher ABIS can process ... accuracy using any combination of fingerprint, face or ... MegaMatcher SDK and MegaMatcher Accelerator ...
(Date:4/28/2016)... Sweden , April 28, 2016 First ... M (139.9), up 966% compared with the first quarter of 2015 ... profit totaled SEK 589.1 M (loss: 18.8) and the operating margin ... 7.12 (loss: 0.32) Cash flow from operations was SEK ... The 2016 revenue guidance is unchanged, SEK 7,000-8,500 M. ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... NC (PRWEB) , ... June 24, 2016 , ... Researchers ... the most commonly-identified miRNAs in people with peritoneal or pleural mesothelioma. Their findings are ... to read it now. , Diagnostic biomarkers are signposts in the blood, lung ...
(Date:6/23/2016)... June 23, 2016 /PRNewswire/ - FACIT has announced ... biotechnology company, Propellon Therapeutics Inc. ("Propellon" ... commercialization of a portfolio of first-in-class WDR5 inhibitors ... such as WDR5 represent an exciting class of ... precision medicine for cancer patients. Substantial advances have ...
(Date:6/23/2016)... -- The Prostate Cancer Foundation (PCF) is pleased to announce 24 new ... prostate cancer. Members of the Class of 2016 were selected from a pool ... Read More About the Class of 2016 PCF Young Investigators ... ... ...
(Date:6/23/2016)... ... 23, 2016 , ... STACS DNA Inc., the sample tracking software company, today ... Laboratory, has joined STACS DNA as a Field Application Specialist. , “I am ... and COO of STACS DNA. “In further expanding our capacity as a scientific integrator, ...
Breaking Biology Technology: