Navigation Links
Arsenic exposure activates an oncogenic signaling pathway; leads to increased cancer risk

PHILADELPHIA Researchers have found a new oncogenic signaling pathway by which the environmental toxin arsenic may lead to adverse health effects, including bladder cancer. These study results are published in Cancer Research, a journal of the American Association for Cancer Research.

"In a collaborative investigation we found that arsenic, at environmentally relevant levels, is capable of activating the Hedgehog pathway and may represent a novel pathway of arsenic-associated diseases, such as bladder cancer," said Margaret R. Karagas, Ph.D., professor in the Department of Community and Family Medicine at Dartmouth Medical School.

"We provide important insight into the etiology of arsenic-induced disease, potentially relevant to the millions of people worldwide who are exposed to arsenic," she said.

Arsenic is a well-known environmental toxin and carcinogen. Studies to date have shown that individuals who live in arsenic contaminated areas of the world exhibit an elevated cancer rate. In many regions of the world, notably Taiwan, Bangladesh and Argentina, high levels of arsenic are detected in drinking water, according to Karagas. Here in the United States, Karagas said that arsenic concentrations above the current maximum contaminant level of 10 μg/L are often found in private, unregulated drinking water systems.

While the correlation between exposure to arsenic resulting in human tumors such as those derived from bladder, lung and skin is well established, the molecular mechanisms driving this connection is unclear.

Karagas and colleagues examined the hypothesis that the secreted protein called Hedgehog, a key oncogenic signaling pathway, might be activated by arsenic. Activation might underlie the mechanism by which arsenic acts as a co-carcinogen.

Using experimental data from cell cultures and results of epidemiologic studies, the researchers found that arsenic activates the Hedgehog signaling by decreasing the stability of the repressor form of GLI3, which is one of the transcription factors that regulate Hedgehog activity. Also, Karagas and colleagues found high levels of arsenic exposure associated with high levels of Hedgehog activity.

"Constitutive Hedgehog signaling has been implicated in a wide spectrum of solid tumors," said Anthony Capobianco, Ph.D., editorial board member of Cancer Research. "This group observed increased Hedgehog activity in a large set of human bladder tumors. Interestingly, they also detected a strong correlation between high-level Hedgehog activity and arsenic exposure in this cohort of bladder cancer patients, supporting their mechanistic findings."

Capobianco is director of the Molecular Oncology Research Program in the Division of Surgical Oncology at the Sylvester Comprehensive Cancer Center, University of Miami, and was not associated with this study.

"This report is the first to link arsenic exposure to activation of the signaling pathway and its potential mediator of arsenic-driven tumors," he said.


Contact: Tara Yates
American Association for Cancer Research

Related medicine news :

1. Store-bought freshwater fish contain elevated levels of mercury, arsenic and selenium
2. Fetal Exposure to Arsenic Affects Genes
3. Arsenic-based therapy shown to help eradicate leukemia-initiating cells
4. People vary widely in ability to eliminate arsenic from the body
5. News brief: Arsenic biomethylation required for oxidative DNA damage
6. Acting Surgeon General Announces National Initiatives to Protect Children by Reducing Exposure to Secondhand Smoke
7. Penn School of Medicine receives $2.3 million to study biomarkers of cigarette smoke exposure
8. Teamsters Applaud Passage of Legislation to Protect Workers From Diacetyl Exposure
9. R rating might be unlikely to affect teens exposure to smoking in movies
10. Occupational exposures may be linked to death from autoimmune disease
11. Low Lead Exposures Can Hurt Kidneys
Post Your Comments:
Related Image:
Arsenic exposure activates an oncogenic signaling pathway; leads to increased cancer risk
(Date:6/27/2016)... ... , ... TherapySites, the leading website and online ... Counseling Association. This new relationship allows TherapySites to continue to extend their ... benefits and promotional offers. , "TCA is extremely excited about this new partnership, ...
(Date:6/26/2016)... ... ... Quality metrics are proliferating in cancer care, and are derived from many ... the beholder, according to experts who offered insights and commentary in the current issue ... the full issue, click here . , For the American Society of Clinical ...
(Date:6/26/2016)... , ... June 26, 2016 , ... Brent Kasmer, a legally blind and certified personal ... personalized through a fitness app. The fitness app plans to fix the two major problems ... offer a one size fits all type program , They don’t eliminate all ...
(Date:6/25/2016)... FL (PRWEB) , ... June 25, 2016 , ... The temporary closing of Bruton Memorial ... Plant City Observer , brings up a new, often overlooked aspect of head lice: the ... closing for fumigation is not a common occurrence, but a necessary one in the event ...
(Date:6/25/2016)... City, Oklahoma (PRWEB) , ... June 25, 2016 ... ... helping both athletes and non-athletes recover from injury. Recently, he has implemented orthobiologic ... the Oklahoma City area —Johnson is one of the first doctors to perform ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... CLEMENTE, Calif. , June 24, 2016  American Respiratory Labs ... company, is now able to perform sophisticated lung assessments in patients, ... Technologies , Inc. Patients are no longer limited ... ndd,s EasyOne PRO ® , ARL patients like Jeanne R. of ... done in the comfort of her own home. ...
(Date:6/24/2016)... According to a new market ... Needles, Safety Pen Needles), Needle Length (4mm, 5mm, 6mm, ... of Purchase (Retail, Non-Retail) - Trends & Global Forecasts ... market for the forecast period of 2016 to 2021. ... by 2021 from USD 1.65 Billion in 2016, growing ...
(Date:6/24/2016)... , June 24, 2016 VolitionRx ... of Dr. Edward Futcher to the ... effective June 23, 2016.Dr. Futcher was also appointed ... Governance Committees.  As a non-executive member of the ... and strategic counsel to VolitionRx in connection with ...
Breaking Medicine Technology: