Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists uncover clues to ’disappearing’ precancers

01.07.2005


New research sheds light on why cervical precancers disappear in some women and not in others. Scientists at the Johns Hopkins Kimmel Cancer Center report in the July 1 issue of Clinical Cancer Research that the reason many of these lesions persist is an unlikely mix of human papilloma virus (HPV) strain and a woman’s individual immune system.



For decades, scientists have known that HPV causes nearly all cases of cancer in the neck of the womb. Most sexually active women – some reports say up to 80 percent – are exposed to HPV and more than half of these women are infected with strains of the virus that could likely turn a precancerous lesion to cancer. But only a small percentage of precancers progress to full-blown cancer, a process that takes years.

To find out why, gynecologic oncologist Cornelia Trimble, M.D., closely monitored 100 women with high-grade, precancerous cervical lesions before standard surgery to remove the abnormal tissue. Some of the lesions – about 28 percent -- regressed by themselves before surgery within a time period considered within the bounds of care standards. But among patients whose pre-cancers lingered, Trimble discovered that women were three times less likely to resolve their lesions if they carried a certain immune system gene and did not have HPV16, the most common strain of the virus.


Trimble was particularly interested in these molecular differences because she is using HPV-targeted vaccines in related studies to treat early cervical lesions before they turn into cancer. "It’s important for us to know the immunologic fingerprint of women who may best benefit from our vaccine," she says. "Some lesions are on the brink of resolving, but may need the vaccine to push them over."

Lesions containing HPV16 alone are the most troublesome and difficult to resolve. In the subset of 44 patients with HPV16 only, their type of immune system made no impact on whether or not their lesion resolved. But in 30 women with non-HPV16 lesions, those who carry a gene called HLA*A201 were three times less likely to clear up their lesions than those without the gene (14.3 percent vs. 42.3 percent). According to Trimble, 40 percent of people carry the HLA*A201 gene, which codes for certain white blood cell proteins.

None of the lesions got worse during the study period, and all unresolved lesions were surgically removed when the observation period ended. "Since none of the lesions progressed after 15 weeks, we can be reasonably assured that this window of time is safe for vaccine treatments," she said.

Trimble is studying a larger group of patients to confirm her results and rule out other potentially confounding factors such as age, smoking status, and contraceptive method, which may influence how these lesions clear. Trimble recently published results linking second-hand cigarette smoke to cervical cancer progression. She also is looking for additional immune system characteristics that could predict mechanisms of immune responses to HPV. This may provide more information on which women have lesions more likely to regress and potentially avoid surgery, plus provide the opportunity to treat early-stage disease.

According to the Centers for Disease Control, an estimated 20 million people in the United States are infected with HPV and up to three-quarters of these have viral strains that are linked to cervical, oral and anal cancers. More than 10,000 cases of cervical cancer are diagnosed in the United States annually.

Vanessa Wasta | EurekAlert!
Further information:
http://www.jhmi.edu

More articles from Health and Medicine:

nachricht Malaria Already Endemic in the Mediterranean by the Roman Period
27.07.2017 | Universität Zürich

nachricht Serious children’s infections also spreading in Switzerland
26.07.2017 | Universitätsspital Bern

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: Physicists Design Ultrafocused Pulses

Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.

Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

Programming cells with computer-like logic

27.07.2017 | Life Sciences

Identified the component that allows a lethal bacteria to spread resistance to antibiotics

27.07.2017 | Life Sciences

Malaria Already Endemic in the Mediterranean by the Roman Period

27.07.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>