Navigation Links
Link between obesity and enhanced cancer risk elucidated

Epidemiological studies indicate that being overweight or obese is associated with increased cancer risk. The most dramatic effect of obesity on cancer risk has been noted for a common form of liver cancer called hepatocellular carcinoma or HCC. Modeling the effect of obesity in mice, researchers at the University of California, San Diego School of Medicine have conclusively demonstrated that obesity is tumor-promoting and have obtained evidence that this effect depends on induction of low-grade, chronic inflammation.

Their results, published January 22 by the journal Cell, may suggest novel therapy to prevent HCC development in obese men who suffer from chronic liver disease.

Michael Karin, PhD, Distinguished Professor of Pharmacology in UCSD's Laboratory of Gene Regulation and Signal Transduction, who led the study, found that obesity enhanced the development of HCC by stimulating the production of tumor-promoting cytokines interleukin-6 (Il-6) and tumor necrosis factor (TNF) that also cause chronic inflammation. Production of these signaling molecules, which are elevated in obese mice and in humans, causes inflammation of the liver and activation of a tumor-promoting transcription factor, a protein called STAT3. This protein in turn activates the formation and growth of liver cancer.

The primary role of TNF is in the regulation of immune cells, but its deregulated production can cause diseases such as rheumatoid arthritis or Crohn's disease. Ironically, while TNF was also tested for its ability to kill cancer, its chronic production was found to actually enhance tumor development.

IL-6 is known to be involved in the pathogenesis of rheumatoid arthritis, but previous work in the Karin lab has shown that IL-6 also contributes to the chronic inflammation that leads to liver cancer. HCC a devastating complication of chronic liver disease and inflammation caused by risk factors such as hepatitis B and C viruses, or alcoholic liver disease makes up the majority of liver cancers in humans and is the third-leading cause of death worldwide. Recent epidemiological studies have confirmed the critical role of IL-6 in the progression of viral hepatitis to HCC in humans. However, the mechanisms by which obesity strongly increased the risk of HCC had remained a mystery.

"The chronic inflammatory response caused by obesity and enhanced production of circulating IL-6 and TNF may also increase the risk of other cancers," Karin added.

The actual increase in cancer risk is dependent on the type of cancer and the body-mass-index (BMI). The largest effect of BMI higher than 25 (the recommended BMI level) is seen on HCC; the risk of this type of liver cancer is increased by up to 4.5-fold in men with a BMI of between 35 and 40. But the effect of excess body weight increases the risk of all cancers 1.5-fold in men and 1.6-fold in women, according to Karin.

"In addition to HCC, obesity markedly increases the risk of pancreatic, gastrointestinal tract and kidney cancers," he said. "Given the prevalence of obesity in the Western and developing worlds, even a modest increase in cancer risk represents a major public health problem."

The new UCSD research suggests that anti-TNF drugs, currently used in the treatment of chronic inflammatory diseases, may be used to prevent HCC development in obese men who suffer from chronic liver disease. According to the studies in mice, inhibition of TNF signaling may even prevent hepatosteatosis, or accumulation of fat in the liver.


Contact: Debra Kain
University of California - San Diego

Related medicine news :

1. Comparison of obstetric outcomes between on-call and patients own obstetricians
2. Mailman School of Public Health study examines link between racial discrimination and substance use
3. New link between estrogen and breast cancer
4. Link Uncovered Between Benign Prostatic Hyperplasia and NSAIDs, Says Harvard Mens Health Watch
5. Link Between Chronic Pain and Insomnia Uncovered at PAINWeek 2007
6. Scientists demonstate link between genetic variant and effectiveness of smoking cessation meds
7. Researchers discover correlation between GERD and obesity in females
8. NIH awards $10.8M to Columbia to study connection between diabetes and heart disease
9. Researchers Pinpoint Link Between Caloric Restriction and Longevity
10. Link Between Air Pollution, Stroke Gets Clearer
11. No Link Between Anti-Nausea Drug, Heart Trouble
Post Your Comments:
(Date:6/25/2016)... ... June 25, 2016 , ... Dr. Calvin ... injury. Recently, he has implemented orthobiologic procedures as a method for treating his ... of the first doctors to perform the treatment. Orthobiologics are substances that orthopaedic ...
(Date:6/24/2016)... ... , ... A recent article published June 14 on E Online ... on to state that individuals are now more comfortable seeking to undergo not only ... calf and cheek reduction. The Los Angeles area medical group, Beverly Hills Physicians (BHP) ...
(Date:6/24/2016)... , ... June 24, 2016 , ... Marcy was in a crisis. Her son James, ... out at his family verbally and physically. , “When something upset him, he couldn’t control ... use it. He would throw rocks at my other children and say he was going ...
(Date:6/24/2016)... ... June 24, 2016 , ... Dr. Amanda Cheng, an ... Dr. Cheng has extensive experience with all areas of orthodontics, including robotic Suresmile ... orthodontics. , Micro-osteoperforation is a revolutionary adjunct to orthodontic treatment. It can ...
(Date:6/24/2016)... ... June 24, 2016 , ... People across the U.S. are sharpening their pencils ... an essay contest in which patients and their families pay tribute to a genetic ... 2016 National Society of Genetic Counselors (NSGC) Annual Education Conference (AEC) this September. ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... , June 23, 2016  MedSource announced ... as its e-clinical software solution of choice.  This ... best possible value to their clients by offering ... The preferred relationship establishes nowEDC as the EDC ... for MedSource,s full-service clients.  "nowEDC has long been ...
(Date:6/23/2016)... INDIANAPOLIS , June 23, 2016 Roche ... received 510(k) clearance for its Elecsys BRAHMS PCT (procalcitonin) ... severe sepsis or septic shock. With this clearance, Roche ... provide a fully integrated solution for sepsis risk assessment ... associated with bacterial infection and PCT levels in blood ...
(Date:6/23/2016)... Calif. , June 23, 2016 ... CST on Thursday, July 7, 2016 , , , , ... ) , , , , EXPERT PANELISTS:  , , ... Naik; Senior Industry Analyst, Christi Bird; Senior Industry Analyst, Divyaa Ravishankar ... The global pharmaceutical industry is witnessing an exceptional ...
Breaking Medicine Technology: