Navigation Links
MicroRNA molecule increases number of blood stem cells, may help improve cancer treatment
Date:8/4/2010

Investigators have identified a new mechanism that controls the number of hematopoietic stem cells cells that give rise to all blood and immune system cells. In a report in the online Early Edition of Proceedings of the National Academy of Sciences, researchers from Massachusetts General Hospital (MGH) and the Harvard Stem Cell Institute identify a tiny RNA molecule that increases the number of these blood stem cells, an advance that may improve treatment of blood system cancers.

"This novel molecule raises blood stem cell numbers by suppressing the normal cell-death process," explains David Scadden, MD, director of the MGH Center for Regenerative Medicine and senior author of the report. "We've known that these non-coding RNAs can define what an immature cell will become, but none has previously been identified that can tell a blood system stem cell whether to live or die."

MicroRNAs short strands of RNA not involved in the production of proteins bind to and silence the expression of their target genes and play important roles in cellular development and differentiation, including the process by which hematopoietic stem cells (HSCs) mature into red or white blood cells. Since the process that controls the size of the HSC population is unknown, the researchers investigated whether microRNAs were involved. They found that loss of the enzyme Dicer, known to be essential to the generation of microRNAs, caused the death of HSCs, supporting the involvement of microRNAs in maintaining HSC levels.

Futher investigation identified a cluster of microRNAs present at enhanced levels in HSCs and showed that one of them, miRNA-125a, increased numbers of HSCs by protecting them from the cell-death process that normally limits cellular populations. The protective effects of miRNA-125a were only seen at the stem-cell level and may involve suppression of the cell-death protein Bak1.

A related PNAS study from researchers at California Institute of Technology, also released online, found that elevated levels of a related molecule called miRNA-125b in HSCs could lead to an aggressive form of leukemia in mice. "These molecules modify cellular numbers in ways that can be both beneficial and detrimental, so it will be important to understand the differences," Scadden explains.

"We're now looking at ways to expand the stem cell population to briefly turn on the anti-cell-death protection to overcome limited levels of stem cells that can restrict the use of stem cell transplantation for patients with blood system failure and blood-cell cancers. Accomplishing that could make life-saving stem cell transplants available to more patients," he adds. Scadden is the Gerald and Darlene Jordan Professor of Medicine at Harvard Medical School and co-director of the Harvard Stem Cell Institute.


'/>"/>

Contact: Sue McGreevey
smcgreevey@partners.org
617-724-2764
Massachusetts General Hospital
Source:Eurekalert

Related medicine news :

1. Scientists identify microRNA as possible cause of chemotherapy resistance
2. Study links microRNA to shut-down of DNA-repair genes
3. Cancer cells show rewired, fragmented microRNA networks
4. IU research team discovers TB disease mechanism and molecule to block it
5. Tiny molecules may tell big story about cardiovascular disease risk
6. New Cancer-Fighting Strategy Focuses On Signaling Molecules
7. Small molecule with high impact
8. Sigma-Aldrich Reaches Agreement to Sell Pfizers Bioactive Small Molecule Compounds
9. Inflammation Molecule May Determine Fat Levels
10. Exploring the Davids and Goliaths of therapeutic molecules
11. ACS Webinar focuses on drug discovery process for small molecule therapeutics
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/12/2016)... ... February 12, 2016 , ... Each year, the American Physical ... in Anaheim, CA at the Anaheim Convention Center. Almost 10,000 physical therapists across the ... products in action, learn more about their chosen field and network with their colleagues. ...
(Date:2/12/2016)... Atlanta, GA (PRWEB) , ... February 12, 2016 ... ... and relationship-marketing firm announced that nominations have closed for the ISE Southeast Awards ... categories will be announced at the ISE® Southeast Executive Forum and Awards Gala ...
(Date:2/12/2016)... , ... February 12, 2016 , ... Every winter, someone ... This winter the West Penn Burn Center, part of the Allegheny Health ... to bring you the “Space Heaters Need Space” campaign. , “Space ...
(Date:2/12/2016)... ... ... The Jones Agency, a family owned insurance company with offices serving Arlington, Dallas, ... with the Tarrant Area Food Bank in the hopes of alleviating hunger for nearby ... Tarrant County Food Bank offers hope and security to the one in six Texas ...
(Date:2/12/2016)... ... February 12, 2016 , ... Young Asset Protection, a full ... of the latest charity campaign in their community enrichment program. Art Expression utilizes ... worthy cause are currently being accepted at: http://artexpressioninc.org/ . , Art Expression ...
Breaking Medicine News(10 mins):
(Date:2/11/2016)... -- The primary goal of this research is to ... usage of liquid biopsy. Key information the survey seeks ... of liquid biopsy adoption amidst future users - Predominantly ... - Sample inflow to conduct liquid biopsy tests - ... so on. - Correlation analysis of sample type and ...
(Date:2/11/2016)... SAN FRANCISCO , Feb. 11, 2016  Kindred ... focused on saving and improving the lives of pets, ... Technical Section of the New Animal Drug Application (NADA) ... the pivotal field study (KB0120) of Zimeta for the ... by the Company. --> ...
(Date:2/11/2016)... Feb. 11, 2016 Potrero Medical, Inc., the developer ... announce the appointment of George M. Rapier, III , ... Antonio, TX , WellMed is one of the nation,s ... and HMO members in Texas and ... out of his own internal medicine practice, he has been ...
Breaking Medicine Technology: