Navigation Links
High HPV concentrations combined with smoking significantly raise risks of cervical cancer

Cigarette smoking and concurrent infection with high levels of the virus associated with cervical cancer can increase cancer risk by as much as 27 times, according to a study published in the November 2006 issue of Cancer Epidemiology, Biomarkers & Prevention.

Anthony Gunnell, a medical biostatistician and epidemiologist and colleagues at the Karolinska Institutet in Stockholm reviewed the medical exams of women with non-invasive cervical cancer in situ (the most common type) and cancer-free women in one of the largest studies to date to examine the relationships between smoking and the human papilloma virus (HPV). The virus and smoking behavior have long been associated with the disease, but not enough evidence has come forth to determine how either may cause the disease.

Gunnell's study, in fact, suggests that both may create a biochemical synergy that propels the disease. The researchers looked at "Pap" smear examination data from 105,760 Swedish women and identified 499 women with cervical cancer in situ, along with 499 cancer-free women as controls. For these women, they compared their smoking behavior with concentrations (known as viral load) of HPV-16, the viral strain most associated with cervical cancer. The researchers found that a combination of high viral loads and smoking during the time they were initially examined resulted in very high risk of later cervical cancer.

"We were surprised to see this dramatically increased risk among women with high viral loads who smoked," Gunnell said.

Among their findings:

  • Women who smoked and had a high HPV-16 load during their first exam had a 27-fold increased risk of later cancer than women who smoked but did not have an HPV infection.
  • Women who were positive for HPV-16 (irrespective of amount of viral load) and were smokers had a 14-fold increased risk over women who were HPV-16 negative and smoked.
  • Nonsmoking women with high HPV -16 loads had just a 6-fold risk compared to HPV-negative nonsmokers.

"Our initial analyses centered on whether smoking was an independent risk factor for cervical cancer," said Gunnell. "Clearly, both exposures need to be present at the same time for there to be interaction.

"Our study would imply a synergistic action between HPV and smoking that would greatly increase the likelihood of women developing cervical cancer if they are HPV-positive smokers. This would put them in a risk group worthy of careful monitoring."

The study, which also may partly explain why some women may not get cervical cancer despite smoking behavior or being HPV-positive, had too few women with high viral loads for the researchers to declare both smoking and HPV, by themselves, caused the disease. But since it was one of the largest studies to examine this relationship, it strongly suggests directions that future research should take to explore a causative effect.

The researchers also found a relationship between smoking duration and cancer. "We found a statistically significant multiplicative interaction between the duration of smoking and HPV presence causing cervical cancer," Gunnell said. "One explanation for this interaction could involve the influence of smoking on persistence of HPV infection, probably due to localized immune suppression. Conversely, it could be related to the progression of neoplastic growth, since HPV and smoking appear to alter the levels of certain cytokines, which are involved in controlling abnormal cell growth. More likely, the combination of both mechanisms are contributory factors.

In any event, confirmation of an interaction between cigarette smoking and HPV in cervical cancer development is of vital importance to public health, considering the widespread exposure to the virus and cigarette smoking in young women at risk for the disease, he said.

Cervical cancer is one of the leading causes of cance r deaths worldwide, and death rates are particularly high in developing countries. Although rates of incidence and mortality have dropped by 50 percent in the past 20 years, out of the 9,700 women diagnosed just in the United States this year, 3,700 will die. Early diagnosis and treatments have helped curb mortality rates, but the disease still remains one of the world's deadliest. In addition, it remains more common among Hispanic and African-American women.


Source:American Association for Cancer Research

Related biology news :

1. Vaccine combined with short-term postexposure antibiotics protects monkeys from inhalational anthrax
2. Research shows smoking adds a decade to reproductive age of IVF patients
3. OHSU research shows vitamin C counteracts some negative impacts of smoking on unborn babies
4. Indias smoking gun: Dino-killing eruptions
5. Alcoholism, smoking and genetics among Plains American Indians
6. Both alcoholism and chronic smoking can damage the brains prefrontal cortex
7. Researchers test new way to quit smoking
8. Blood test predicts success of quitting smoking using the nicotine patch
9. Quitting smoking improves lung function considerably
10. Cigarette smoking impedes tendon-to-bone healing
11. Heavy smoking cuts womens chance of pregnancy -- even with donated oocytes
Post Your Comments:

(Date:6/27/2016)... June 27, 2016 Research and Markets has ... 2016-2020" report to their offering. ... America to grow at a CAGR of 12.28% during ... based on an in-depth market analysis with inputs from industry experts. ... the coming years. The report also includes a discussion of the ...
(Date:6/22/2016)... -- The American College of Medical Genetics and Genomics was once ... one of the fastest-growing trade shows during the Fastest 50 ... Las Vegas . Winners ... each of the following categories: net square feet of paid ... The 2015 ACMG Annual Meeting was ranked 23 out of ...
(Date:6/22/2016)... , June 22, 2016   ... management and verification solutions, has partnered with ... software solutions for Visitor Management, Self-Service Kiosks ... provides products that add functional enhancements to ... provides corporations and venues with an automated ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... , June 27, 2016  Alex,s Lemonade Stand ... that that it will open a state-of-the-art bioinformatics lab, ... cancer research. This announcement comes as Liz Scott ... the National Cancer Moonshot Summit in Washington, ... Biden as a participant and advocate of pediatric cancer ...
(Date:6/27/2016)... , June 27, 2016  Global demand for ... percent through 2020 to $7.2 billion.  This market ... beverages, cleaning products, biofuel production, animal feed, and ... diagnostics, and biocatalysts). Food and beverages will remain ... by increasing consumption of products containing enzymes in ...
(Date:6/27/2016)... GUELPH, ON , June 27, 2016 /PRNewswire/ - BIOREM ... it has been advised by its major shareholders, Clean ... LP, United States based venture ... common shares of Biorem (on a fully diluted, as ... for the disposition of their entire equity holdings in ...
(Date:6/27/2016)... DIEGO , June 27, 2016  Sequenom, Inc. ... committed to enabling healthier lives through the development of ... Court of the United States ... courts that the claims of Sequenom,s U.S. Patent No. ... patent eligibility criteria established by the Supreme Court,s Mayo ...
Breaking Biology Technology: