Navigation Links
Arsenic exposure activates an oncogenic signaling pathway; leads to increased cancer risk
Date:2/23/2010

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
tara.yates@aacr.org
267-646-0558
American Association for Cancer Research
Source:Eurekalert  

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:
*Name:
*Comment:
*Email:
Related Image:
Arsenic exposure activates an oncogenic signaling pathway; leads to increased cancer risk
(Date:6/25/2016)... ... ... First Choice Emergency Room , the largest network of independent freestanding emergency ... its new Mesquite-Samuell Farm facility. , “We are pleased to announce Dr. Ogunleye ... M. Muzzarelli, Executive Medical Director of First Choice Emergency Room. , Dr. Ogunleye ...
(Date:6/25/2016)... ... June 25, 2016 , ... Dr. Calvin Johnson has ... he has implemented orthobiologic procedures as a method for treating his patients. The ... first doctors to perform the treatment. Orthobiologics are substances that orthopaedic surgeons use ...
(Date:6/25/2016)... ... June 25, 2016 , ... Conventional wisdom preaches the benefits ... terms of the latter, setting the bar too high can result in disappointment, perhaps ... slow progress toward their goal. , Research from PsychTests.com reveals that ...
(Date:6/24/2016)... ... June 24, 2016 , ... Those who have experienced traumatic events may ... to unhealthy avenues, such as drug or alcohol abuse, as a coping mechanism. To ... for healthy coping following a traumatic event. , Trauma sufferers tend to feel a ...
(Date:6/24/2016)... ... ... a crisis. Her son James, eight, was out of control. Prone to extreme mood shifts ... upset him, he couldn’t control his emotions,” remembers Marcy. “If there was a knife ... and say he was going to kill them. If we were driving on the ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... DUBLIN , June 24, 2016 ... "The World Market for Companion Diagnostic Tests" report to ... World Market for Companion Diagnostics The World ... diagnostic and personalized medicine diagnostics. Market analysis in the report ... Diagnostics Test Market (In Vitro Diagnostic Kits) by Region (N. ...
(Date:6/24/2016)... 2016  Arkis BioSciences, a leading innovator in ... durable cerebrospinal fluid treatments, today announced it has ... is led by Innova Memphis, followed by Angel ... investors.  Arkis, new financing will accelerate the commercialization ... release of its in-licensed Endexo® technology. ...
(Date:6/23/2016)... DUBLIN , June 23, 2016 ... the "Pharmaceutical Excipients Market by Type (Organic Chemical ... Preservative), Formulation (Oral, Topical, Coating, Parenteral) - Global Forecast ... The global pharmaceutical excipients ... 2021 at a CAGR of 6.1% in the forecast ...
Breaking Medicine Technology: