Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

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

20.11.2006
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 cancer 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.

Yarissa Ortiz | EurekAlert!
Further information:
http://www.aacr.org

More articles from Health and Medicine:

nachricht New antibody analysis accelerates rational vaccine design
09.08.2018 | Scripps Research Institute

nachricht Distrust of power influences choice of medical procedures
01.08.2018 | Johannes Gutenberg-Universität Mainz

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

Im Focus: World record: Fastest 3-D tomographic images at BESSY II

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

'Building up' stretchable electronics to be as multipurpose as your smartphone

14.08.2018 | Information Technology

During HIV infection, antibody can block B cells from fighting pathogens

14.08.2018 | Life Sciences

First study on physical properties of giant cancer cells may inform new treatments

14.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>