Science Current Events | Science News | Brightsurf.com
 
Email a Friend Send to a friend
Printer Friendly Print Dual role in breast tissue for a protein involved in leukemia

Dual role in breast tissue for a protein involved in leukemia

June 15, 2009

Estrogen receptor status may modify how a protein that spurs leukemia behaves in the breast

Washington, DC - A protein known to play a role in growth of some types of leukemia appears to have a mixed function in breast cancer development, say researchers from the Lombardi Comprehensive Cancer Center at Georgetown University Medical Center (GUMC).




The findings, presented at the annual meeting of the Endocrine Society in Washington, DC, indicate that the function of this protein, known as Stat5a, may be different in developing breast cancer cells that are estrogen receptor-positive as compared to estrogen receptor-negative. When estrogen receptor levels were overexpressed, loss of Stat5a reduced development of a lobular type of preneoplasia. However, when estrogen receptor levels were normal, loss of Stat5a not only had no effect on reducing preneoplasia, but increased susceptibility to carcinogen-induced breast cancer. The results illustrate the importance of breast cancer heterogeneity when testing new therapeutic targets.

The researchers say Stat5a could be a target for treatment of leukemia, but add, "If Stat5a is to be used as a drug target for leukemia or other cancers, it is important to fully understand how altering its function impacts the breast, especially since it appears it may play different roles in different types of breast cancer," says the study's lead author, Anne Miermont, MS, a doctoral graduate student in tumor biology at Georgetown University Medical Center.

Stat5a is a member of the STAT family of proteins, which are key to regulating cell growth and differentiation. Because they have been found to be over-expressed in leukemia, Miermont and Priscilla Furth, MD, a professor of oncology, sought to see if they were important in breast cancer development. Estrogen receptors are over-expressed in more than half of human breast cancers, so the investigators set up studies to test if the function of Stat5a was the same or different in cells with estrogen receptor overexpression.

They found that Stat5a A is rather "two-faced" when it comes to its role in breast tissue. Previous studies had shown that mice born without the gene produce breast cells that are a little less differentiated than they should be, meaning that they are not fully developed enough to participate in milk production. Miermont found that when the animals were exposed to a cancer-causing chemical, they were more likely to develop breast cancer than mice with intact Stat5a genes. At the same time, however, Miermont found that when estrogen receptor was over-expressed, Stat5a collaborated with it to promote growth of a type of precancerous lesion of the breast termed a hyperplastic alveolar nodule.

"Our studies in in vivo mouse models illustrate a dual role for the Stat5a protein in breast tissue. While it can contribute to the growth of one type of precancerous lesion in the breast, this protein also appears to protects mammary cells from carcinogenic exposure," says Miermont.

These findings need to be validated and expanded, Furth says, but she adds that "while Stat5a is obviously a complicated protein that has many functions, the results underscore the need to specifically understand the mechanisms that regulate its different roles in breast cells and how changes in Stat5a activity may affect different types of breast cancer generation."

Georgetown University Medical Center



Related Breast Cancer Current Events and Breast Cancer News Articles Breast Cancer Current Events and Breast Cancer News RSS Breast Cancer Current Events and Breast Cancer News RSS
New figures on cancer in Europe show a steady decline in mortality but big variations
New figures on deaths from cancer in Europe show a steady decline in mortality between the periods 1990-1994 and 2000-2004. Deaths from all cancers in the European Union (EU) between these two periods fell by nine percent in men and eight percent in women, with a large drop among the middle-aged population.

Elastography reduces unnecessary breast biopsies
Elastography is an effective, convenient technique that, when added to breast ultrasound, helps distinguish cancerous breast lesions from benign results, according to an ongoing study presented today at the annual meeting of the Radiological Society of North America (RSNA).

First live targeting of tumors with RNA-based technology
Finding and treating a tumor without disturbing normal tissue presents challenges - sometimes the most effective therapies can be invasive and harsh.

Menopause-cardiology consensus statement on cardiovascular disease and on HRT
A menopause-cardiology consensus statement has called for direct action to prevent cardiovascular disease (CVD) in menopausal women. The statement also concludes that there is little evidence of increased CVD risk in taking HRT.

Researchers Identify Role of Gene in Tumor Development, Growth and Progression
Virginia Commonwealth University Massey Cancer Center and VCU Institute of Molecular Medicine researchers have identified a gene that may play a pivotal role in two processes that are essential for tumor development, growth and progression to metastasis.

UCLA researchers create 'fly paper' to capture circulating cancer cells
Just as fly paper captures insects, an innovative new device with nano-sized features developed by researchers at UCLA is able to grab cancer cells in the blood that have broken off from a tumor.

Fertility procedures need not delay breast cancer treatment for younger women
A new study published in the November issue of the Journal of the American College of Surgeons shows that breast cancer patients under 40 years old who undergo fertility preservation do not face a significant delay in the treatment of their disease when their care is coordinated in a timely fashion.

Coffee break: Compound brewing new research in colon, breast cancer
A compound in coffee has been found to be estrogenic in studies by Texas AgriLife Research scientists.

Drugs to treat anemia in cancer patients linked to thromboembolism
Medications frequently given to cancer patients to reduce their risk of anemia are associated with an increased risk of deep vein thrombosis or pulmonary embolism, according to new research led by Dawn Hershman, M.D, M.S., co-director of the breast cancer program at the Herbert Irving Comprehensive Cancer Center at NewYork-Presbyterian Hospital/Columbia University Medical Center.

Discovery in worms by Queen's researchers points to more targeted cancer treatment
Researchers at Queen's University have found a link between two genes involved in cancer formation in humans, by examining the genes in worms. The groundbreaking discovery provides a foundation for how tumor-forming genes interact, and may offer a drug target for cancer treatment.
More Breast Cancer Current Events and Breast Cancer News Articles
New Balance Women's Lace Up X Out Breast Cancer Tech Tee (Athletic Grey, Small)

New Balance Women's Lace Up X Out Breast Cancer Tech Tee (Athletic Grey, Small)
by New Balance

The New Balance X Out Breast Caner Tee has a soft hand and clearly states how everyone feels!

1149 WOMENS VINTAGE BLACK ADJUSTABLE FATIGUE CAP w/PINK STRIPES & ''BREAST CANCER'' RIBBON

1149 WOMENS VINTAGE BLACK ADJUSTABLE FATIGUE CAP w/PINK STRIPES & ''BREAST CANCER'' RIBBON
by Rothco

A portion of these proceeds go to the Babylon Breast Cancer Coalition- For Life, For Hope, For Change, For the Future Visit www.babylonbreastcancer.org for more information.

Breast Cancer Survival Manual, Fourth Edition: A Step-by-Step Guide for the Woman With Newly Diagnosed Breast Cancer

Breast Cancer Survival Manual, Fourth Edition: A Step-by-Step Guide for the Woman With Newly Diagnosed Breast Cancer
by John Link (Author)

A completely updated edition of the definitive guide for patients with breast cancer
The new fourth edition of The Breast Cancer Survival Manual provides essential updates on treatment and care, enhancing the basic information that has made this the most trusted guide for women diagnosed with breast cancer for the past decade. This edition includes the most current advice on • getting a second opinion: why it’s important, what questions    to ask, and how to decide which team of doctors is best for you
• updates on genetic testing and how doctors are using
   the results to tailor care for each patient
• navigating new types of radiation, the herceptin
   breakthrough, and improved reconstruction surgeries
Conscious of the rapidly evolving spectrum of...

Sunbeam Camelot Microplush Heated Throw, Breast Cancer Awareness Pink

Sunbeam Camelot Microplush Heated Throw, Breast Cancer Awareness Pink
by Sunbeam

Soft comfortable fabric that you can cuddle up with anywhere in your house. Use it on the couch while curling up to read a good book or in a chair while watching your favorite show. This throw is 50"x60", with a primstyle control which features 3 warming settings and 3 hour auto-off. So turn on your warming blanket, turn off your thermostat and save on your heating bill. Warm up to a good cause! Sunbeam is joining the fight against breast cancer. Through the purchase of this pink throw, sunbeam will donate $1.00 to city of hope for breast cancer research, treatment and education* up to $25,000. Program ends april 30, 2009. "to save lives and end breast cancer forever by empowering people, ensuring quality care for all, and energizing science to find the cures." *to learn more about...

Hope Courage Strength Pink Ribbon Breast Cancer Awareness Expressively Yours Bracelet

Hope Courage Strength Pink Ribbon Breast Cancer Awareness Expressively Yours Bracelet
by MyJewelThief



Wrangler Women's Tough Enough To Wear Pink Breast Cancer Awareness Jacket,Pink,X-Large

Wrangler Women's Tough Enough To Wear Pink Breast Cancer Awareness Jacket,Pink,X-Large
by Wrangler

Are you tough enough to wear pink? That is the question the western industry asked 12/9/05 at the Wrangler National Finals Rodeo (Wrangler NFR), the "Super Bowl of pro rodeo," as it launched Tough Enough to Wear Pink (TETWP). TETWP is a multi-year, western-industry-wide fundraiser to raise awareness and funds for breast cancer research. TETWP partners are ponying up to support this cause by manufacturing pink merchandise with proceeds benefiting breast cancer research. By wearing this Tough Enough to Wear Pink shirt you are helping in the fight against breast cancer. This TETWP shirt is a pink cotton plaid. Import. Tough Enough to Wear Pink. long sleeve zip front jacket with zippered front slash pockets and the breast cancer embroidery on left chest. 100% Polyester Fleece/100% Nylon...

Raymond Geddes National Breast Cancer Foundation Pen (67709)

Raymond Geddes National Breast Cancer Foundation Pen (67709)
by Raymond Geddes

Breast Cancer Awareness Pen, Join Geddes in supporting the National Breast Cancer Foundation and the fight against Breast Cancer. Assortment contains pink pens with pink ribbons. Retractable, black in pen ink. 5 1/2" long.

Just Get Me Through This!: The Practical Guide to Breast Cancer

Just Get Me Through This!: The Practical Guide to Breast Cancer
by Deborah A. Cohen (Author), M.D., Robert M. Gelfand (Author)



Fox Run Breast Cancer Awareness Baking Set

Fox Run Breast Cancer Awareness Baking Set
by Fox Run

Support Breast Cancer awareness in a sweet way with this five piece set. Bake cookies using the ribbon cookie cutters or cupcakes using the white paper bake cups with the pattern of pink ribbons. Decorate both with the included 4 in 1 sprinke assortement jar. The set also includes a pink silicone spoon spatula to help mix up your favorite batch of cookie dough.

Find the Cure Pink Breast Cancer Awareness Wristband

Find the Cure Pink Breast Cancer Awareness Wristband
by sci

Find The Cure Pink Breast Cancer Awareness wristband

© 2009 BrightSurf.com