Navigation Links
COX-2 expression is marker for cancer development in some benign breast biopsies
Date:3/11/2008

ROCHESTER, Minn. -- Its a good news, bad news situation. Some women who have a breast biopsy are told that while they dont have cancer, they do have atypical hyperplasia -- cells that arent quite normal and might become cancerous someday. This happens to one-fourth of women undergoing breast biopsies but no one knows which individuals are at risk.

In their quest to discover who is at risk, researchers at Mayo Clinic (http://mayoresearch.mayo.edu/mayo/research/womens_cancer/breast_excellence.cfm) are building a biopsy profile to try to predict cancer outcome, and in the March 11 online edition of the Journal of the National Cancer Institute (http://jnci.oxfordjournals.org/rss/recent.xml), they report finding a new variable to add to this profile.

The research team discovered that women whose atypia tissue expressed COX-2 enzymes were more likely to develop breast cancer subsequently, and that the more the enzyme expressed, the higher the risk.

Specifically, 20 years after a biopsy in which atypia was found, 31 percent of women with high levels of COX-2 in their atypia sample had developed breast cancer, versus 14 percent of those with no COX-2 expression. For those with moderate levels of COX-2, 24 percent had developed breast cancer.

Based on these findings, COX-2 expression in atypia may be a biomarker of risk of progression to breast cancer, says the studys senior investigator, Mayo Clinic oncologist Lynn Hartmann, M.D (http://mayoresearch.mayo.edu/mayo/research/staff/hartmann_lc.cfm). COX-2 is a relevant candidate because it drives a number of malignant features and has been shown to be important in breast cancer.

Each year in the United States, about 1 million women have a benign breast biopsy; and some of them receive the worrisome news that they have atypical hyperplasia, Dr. Hartmann says. If other studies validate these findings, she notes that one strategy to help manage patients may be to use a COX-2 inhibiting agent, such as celecoxib (http://en.wikipedia.org/wiki/Celecoxib)or rofecoxib (http://en.wikipedia.org/wiki/Rofecoxib), to prevent breast cancer from developing. This study raises the possibility of targeting COX-2 in selected women to reduce their risk of breast cancer, she says.

In the biopsy profile thus far, the Mayo risk model includes age, the number of regions of atypical cells in the biopsy, COX-2 expression and the status of the normal lobules in the breast.

Our goal is to individualize risk for breast cancer so that we can provide effective care and risk reduction for each of our patients, says Dr. Hartmann.

Cyxlooxygenase (COX) enzymes produce prostaglandin compounds responsible for pain and inflammation, and nonsteroidal anti-inflammatory drugs (NSAIDs) are designed to reduce expression of COX enzymes, although some NSAID use has been associated with side effects (most notably possible kidney failure). COX-2 is a form of COX that is not usually found in normal tissues but which has been associated with several cancers, including ductal carcinoma in situ and invasive breast cancers.

In this study, researchers examined breast biopsy samples that contained atypia for COX-2 expression which has never been done before.

Investigators looked at 235 women who had a breast biopsy following a mammogram at Mayo Clinic from 1967 through 1991, and who were diagnosed with the atypical hyperplasia cell growth disorder.

During an average follow-up period of 15 years, 41 (17 percent) of the women developed breast cancer. The average time for that breast cancer to be diagnosed was 11.4 years.

The researchers examined the biopsies for the level of COX-2 expression and for other variables, such as the number of areas (or foci) within the biopsy that contained atypical growth. They found that moderate expression was identified in 71 (30 percent) of the samples and that 34 (14 percent) of the biopsies exhibited strong expression of the enzyme.

The researchers calculated that, among the women in the study group, the absolute risk of developing breast cancer 15 years after a diagnosis of atypical hyperplasia was 13 percent in biopsies with little or no COX-2 expression, 19 percent with moderate COX-2 expression, and 25 percent with strong COX-2 expression. In women who had been followed for 20 years or more, the association was more definitive: stratification of risk was 14 percent, 24 percent, and 31 percent, respectively. (Because the participants had atypical hyperplasia, they were all at increased baseline risk of developing breast cancer.)

The finding that risk of later breast cancer was associated with increasing levels of COX-2 expression was of borderline statistical significance (p=.07), likely due to the small sample size Dr. Hartmann says. But higher expression levels were tightly linked to an increased number of abnormal foci in the biopsy, which we had earlier found to be a strong risk factor for breast cancer.

The researchers also assessed the relative risk of developing breast cancer, based on COX-2 expression in atypical hyperplasia, compared to a control population of unaffected women, and found that little COX-2 expression was associated with 2.6 times the risk, moderate COX-2 expression increased risk by 3.5 times, and a strong expression of COX-2 elevated risk by more than 5.6 times, compared to women in the general population.

COX-2 appears to be a biomarker that further stratifies breast cancer risk among women with atypia and may be a relevant target for chemoprevention strategies, says Dr. Hartmann.


'/>"/>

Contact: Russ Vanderboom
newsbureau@mayo.edu
507-284-5005
Mayo Clinic
Source:Eurekalert

Related medicine news :

1. Altered expression of ultraconserved noncoding RNAs linked to human leukemias and carcinomas
2. 10th Anniversary of Revolutionary Teaching Approach that Offers the Severely Disabled the Gift of Self-Expression - Through Painting
3. New study shows that therapeutic gene expression can be sustainable for 1 year
4. Xceed Molecular Launches Ziplex(R) Automated Gene-Expression System at the Association for Molecular Pathology, Booth 84/85
5. Flip-flopping gene expression can be advantageous
6. Facial expressions have greater impact on kids with bipolar disorder
7. Biolytix to Offer Industrial Gene Expression Analysis and Genotyping Services Using Affymetrix GeneChip(R) Technology
8. iNOS expression may links chronic biliary inflammation to malignant transformation
9. How does Fu-Zheng-Jie-Du-Decoction act on PTEN expression in hepatocellular carcinoma?
10. Jefferson scientists uncover role of cancer stem cell marker: controlling gene expression
11. NEJM editorial on significance and limitations of new lupus gene expression research
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/5/2016)... Kansas (PRWEB) , ... May 05, 2016 , ... ... that some macroalgae can use ultraviolet light A (UV-A) for photosynthesis, researchers Juntian ... of red, green, and brown seaweeds. The pair observed that when photosynthetically active ...
(Date:5/5/2016)... MS (PRWEB) , ... May 05, 2016 , ... ... medical conditions and Make-A-Wish grants the most heartfelt wishes of these children. ... rounds of medical treatment. President and CEO of Make-A-Wish Mississippi, Brent Wilson ...
(Date:5/5/2016)... ... 2016 , ... Long Island’s fastest growing comprehensive eye care provider, North ... Kathleen Van Valkenburg, MD as part of their ongoing effort to increase ophthalmic coverage ... managing partner of North Shore Eye Care. , “We are extremely proud to ...
(Date:5/5/2016)... ... May 05, 2016 , ... TIME for Kids and The ZAC Foundation ... new partnership to reach nearly 1 million children with important water safety messages before ... the leading cause of accidental death in children one to 6 years of age. ...
(Date:5/5/2016)... ... May 05, 2016 , ... In honor of National Nurses Week 2016, ... the United States to thank a nurse who's made a difference in their life. ... the American Red Cross of San Diego/Imperial Counties (up to $10,000) every time someone ...
Breaking Medicine News(10 mins):
(Date:5/5/2016)... , May 5, 2016 Progra m ... trial of Oxitec , s mosquito in ... aegypti by 96 %   ... new plan to fight wild Aedes aegypti, the dangerous mosquito that ... the island of Grand Cayman .  MRCU, a global leader ...
(Date:5/5/2016)... , May 5, 2016 Research ... PET Imaging in Top 5 EU Markets"  report to their ... This report provides information on the current Positron Emission Tomography ... European Markets (T5 EU), which includes France ... , Spain and the ...
(Date:5/5/2016)... DUBLIN , May 5, 2016 /PRNewswire/ ... the addition of the  "Europe Thalassaemia Market ... to their offering.       (Logo: ... research Europe Thalassaemia Market and Competitive Landscape ... Thalassaemia pipeline products, Thalassaemia epidemiology, Thalassaemia market ...
Breaking Medicine Technology: