Navigation Links
RNA snippet suppresses spread of aggressive breast cancer
Date:6/15/2009

CAMBRIDGE, Mass. (June 11, 2009) A low cellular level of a tiny fragment of RNA appears to increase the spread of breast cancer in mouse models of the disease, according to researchers at Whitehead Institute for Biomedical Research.

Measuring levels of this so-called microRNA, which is also associated with metastatic breast cancer in humans, may more accurately predict the likelihood of metastasis (which accounts for 90% of cancer-related deaths) and ultimately help determine patient prognoses.

In the study, whose results are reported in the June 12 issue of Cell, Scott Valastyan, a graduate student in Whitehead Member Robert Weinberg's laboratory, screened patient breast cancer samples for microRNAs with potential roles in metastasis. MicroRNAs are single strands of RNA about 21-23 nucleotides long. Within a cell, a single microRNA can fine-tune the expression of dozens of genes simultaneously. This capability could be particularly important in metastasis, a multi-step process that could be influenced by a single microRNA at several points.

The screened samples were classified as either metastatic cancer or non-metastatic cancer. After analysis, the microRNA miR-31 stood out because of its inverse correlation with metastasis. In samples where a patient's original tumor had not metastasized, the cancer cells retained high levels of the microRNA. But where the tumor had metastasized, the cancer cells came to possess lower levels of miR-31.

The functional role of miR-31 in metastasis regulation was then confirmed in mice. When Valastyan removed miR-31 from normally non-aggressive breast cancer cells and implanted those cells into mice, the cells formed highly aggressive tumors. Mice injected with the cancer cells lacking miR-31 had 6 to 10 times more cancer cells that metastasized to their lungs than did their counterparts implanted with unmodified cancer cells.

To see how increasing miR-31 levels could affect metastasis, Valastyan introduced miR-31 into breast cancer cells that readily metastasize. After injecting these altered cells into mice, the mice had four to 40 times fewer metastases than mice injected with the unaltered cells.

Valastyan says that quantifying miR-31 levels in a patient's cancer cells could one day support a more accurate prognosis. Currently, breast cancers are divided into three major categories, two of which are typically associated with poor prognoses.

"This microRNA seems to be quite unique, in that it seems to provide some prognostic utility across these existing subclassifications [of cancers]," says Valastyan. A better-defined prognosis could help patients determine whether they might benefit from poorly tolerated cancer therapies.

In addition, miR-31 could be a useful target for cancer therapy. Weinberg, who is also a professor of biology at MIT, is cautiously optimistic. "At present, it's quite difficult to inhibit the action or promote the actions of a microRNA in a whole organism," he says, "but in the future, microRNAs like this one might prove to be very important in altering the clinical progression of a tumor or causing it to revert to a more benign state."

This research was supported by the National Institutes of Health (NIH), MIT Ludwig Center for Molecular Oncology, U.S. Department of Defense (DoD), Breast Cancer Research Foundation, Harvard Breast Cancer Specialized Program of Research Excellence (SPORE), and a DoD Breast Cancer Research Program (BCRP) Idea Award.


'/>"/>

Contact: Nicole Giese
giese@wi.mit.edu
617-258-6851
Whitehead Institute for Biomedical Research
Source:Eurekalert

Related medicine news :

1. Protein that suppresses androgen receptors could improve prostate cancer diagnosis, treatment
2. Turmeric extract suppresses fat tissue growth in rodent models
3. Protein switch suppresses skin cancer development
4. Protein suppresses allergic response in mice
5. Guardian Survey Reveals Widespread Lack of Understanding of Health Savings Accounts
6. Drug May Extend Life When Breast Cancer Spreads
7. Spread of Swine Flu in Japan Could Raise WHO Alert to Highest Level
8. Researchers study the human factor in spread of pandemic illness
9. Fiber Technology Products that Help Combat Spread of Superbugs Now Available to the Consumer Market
10. New technique may help detect potential breast cancer spread
11. Genes Linked to Spread of Breast Cancer
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/17/2017)... ... February 17, 2017 , ... Corrective ... Warning Letter, **An FDAnews Webinar**, Feb. 23, 2017 — 1:30 p.m. – 3:00 ... corrective action (CA) and preventive action (PA)? , The methods share techniques and ...
(Date:2/17/2017)... ... February 17, 2017 , ... MAP ... today that Karen Pilley has been promoted to Chief Executive Officer. , ... healthcare paradigm – a shift that demands the transition from pay-for-service to pay-for-performance ...
(Date:2/17/2017)... ... ... Like most hospitals across the nation, Onslow Memorial Hospital is looking for more ... Program (HRRP), the return of a patient to the hospital within 30 days of ... providers are struggling to leverage limited resources and technology, Onslow Memorial Hospital has saved ...
(Date:2/16/2017)... ... February 17, 2017 , ... Harsha Chigurupati ... years of research, development and clinical trials, the founder of Chigurupati Technologies has ... compound of FDA approved ingredients that when infused into alcohol, protect the consumer’s ...
(Date:2/16/2017)... ... February 16, 2017 , ... As a reflection of ... care, NWH has achieved Magnet® recognition for the second time, announced ... The American Nurses Credentialing Center’s Magnet Recognition Program® distinguishes organizations that meet rigorous ...
Breaking Medicine News(10 mins):
(Date:2/17/2017)... DUBLIN , Feb. 17, 2017 ... ("Theravance Biopharma" or the "Company") today announced the ... novel, potent, and orally administered pan-Janus kinase (JAK) ... 12 th Congress of the European Crohn,s ... the Company reported further data from its completed ...
(Date:2/17/2017)... Research and Markets has announced the addition of the "Drug-Eluting ... ... for the US, Canada , Japan ... Latin America , and Rest of World. Annual estimates and ... historic analysis is provided for these markets. Market data and analytics are ...
(Date:2/17/2017)... LOUIS , Feb. 17, 2017   FormFast ... has announced a new partnership with Engage , ... the United States . FormFast will serve as ... of Engage,s implementations with MEDITECH .  ... provides essential functionality to complement and enhance the electronic ...
Breaking Medicine Technology: