Study identifies drug resistance of CLL in bone marrow and lymph nodes
Potential mechanism identified
2010-12-07
(Press-News.org) ORLANDO ––– In research to be presented at the American Society of Hematology (ASH) annual meeting, investigators at Dana-Farber Cancer Institute in Boston offer a new explanation of why chronic lymphocytic leukemia (CLL) tends to recur in the lymph nodes and bone marrow after being cleared from the bloodstream by chemotherapy. Their findings will be reported during in an oral session on Monday, Dec. 6, at 4:45 p.m. in room 315 of the Orange County Convention Center.
To uncover the reasons for CLL's resilience in the marrow and lymph nodes, the researchers employed a technique called BH3 profiling, which had been devised by senior author Anthony Letai, MD, PhD, and his Dana-Farber colleagues in 2005. The technique makes it possible to identify cancer cells that are less likely to undergo mitochondrial apoptosis (a form of programmed cell death involving cell structures called mitochondria) because of alterations in the Bcl-2 family of proteins. These abnormalities can make such cells less susceptible to both standard chemotherapy and novel, targeted agents.
In the current study, Letai and his associates found that when CLL cells from patients were grown with non-cancerous support cells from the bone marrow and lymph nodes, the CLL cells were more resistant to apoptosis – and hence harder to kill with treatment – than were CLL cells from the bloodstream. Using BH3 profiling, they discovered that although circulating CLL cells were likely to die by mitochondrial apoptosis in response to treatment, CLL cells grown among non-cancerous cells were much less likely to die this way. The presence of these normal cells, known as stroma, apparently helped the CLL cells survive, despite receiving treatment that would otherwise have resulted in their death.
"We hope that by clearly identifying the ability of stromal cells to reduce the CLL cells' capability to undergo apoptosis, we can exploit strategies to selectively target the 'help' that stromal cells give to CLL cells," says Letai.
###
The study's lead author is Matthew Davids, MD, of Dana-Farber. Co-authors were Jennifer Brown, MD, PhD, of Dana-Farber, and Adrian Wiestner, MD, PhD, of the National Heart, Lung, and Blood Institute.
This study was supported by the NIH and Leukemia and Lymphoma Society.
Dana-Farber Cancer Institute (www.dana-farber.org) is a principal teaching affiliate of the Harvard Medical School and is among the leading cancer research and care centers in the United States. It is a founding member of the Dana-Farber/Harvard Cancer Center (DF/HCC), designated a comprehensive cancer center by the National Cancer Institute. It provides adult cancer care with Brigham and Women's Hospital as Dana-Farber/Brigham and Women's Cancer Center and it provides pediatric care with Children's Hospital Boston as Dana-Farber/Children's Hospital Cancer Center. Dana-Farber is the top ranked cancer center in New England, according to U.S. News & World Report, and one of the largest recipients among independent hospitals of National Cancer Institute and National Institutes of Health grant funding.
END
ELSE PRESS RELEASES FROM THIS DATE:
2010-12-07
Foreign pests are eating their way through our national forests, destroying majestic scenery and costing taxpayers millions of dollars.
If enforcement efforts to prevent their importation aren't stepped up, irreplaceable resources will be lost forever and taxpayers can expect to fork over billions of dollars by 2019, according to a comprehensive study published today in BioScience.
Researchers at the University of California at Santa Barbara, Michigan State University, the University of Central Florida and the United States Department of Agriculture Forest Service analyzed ...
2010-12-07
San Diego, CA, December 7, 2010 – Obesity in youngsters has risen dramatically in recent decades. Fruit and vegetable (FV) consumption and increased water intake can lower the risk of obesity, as can increased physical activity, but it is not always easy to convince children to eat better and exercise more. In a new study published in the January 2011 issue of the American Journal of Preventive Medicine, researchers found that video games designed to encourage these behaviors were effective.
"Escape from Diab" (Diab) and "Nanoswarm: Invasion from Inner Space" (Nanoswarm) ...
2010-12-07
The London School of Hygiene & Tropical Medicine (LSHTM) has contributed to a study showing that a low dose of aspirin reduces the occurrence of several common cancers. The study is published in today's Lancet.
The work was started and carried out by Professor Peter Rothwell in Oxford, and is based on an overview of several randomised trials of aspirin. These have been primarily concerned with reducing heart attacks, but have also gathered information on deaths from cancer.
The trial contributing most information to the overview has been the Thrombosis Prevention Trial ...
2010-12-07
Scientists have created the highest resolution map of the Sumatran tiger distribution ever produced, revealing that the island now hosts the second largest tiger population on earth. The research, carried out with the Wildlife Conservation Society's Indonesia Program and Forum HarimauKita, will be published in a special issue of Integrative Zoology, on tiger conservation and research methodologies.
Hariyo T. Wibisono and Wulan Pusparini conducted a questionnaire-based survey across the island to identify the status of Sumatran tiger distribution. They found that tigers ...
2010-12-07
The risk of having a heart attack is 60 per cent higher just a year after a patient has been diagnosed with rheumatoid arthritis, according to research published in the December issue of the Journal of Internal Medicine.
Swedish researchers followed 7,469 patients diagnosed with rheumatoid arthritis (RA) between 1995 and 2006, together with 37,024 matched controls without RA to determine the risk of ischaemic heart disease, with particular reference to myocardial infarction (heart attack). The maximum follow-up was 12 years and the median was just over four years.
"Our ...
2010-12-07
Tapping into young people's use of online social networks presents health agencies with a powerful opportunity to help control the rise in HIV and other sexually transmitted infections in homeless youth in Los Angeles. According to new research1 by Sean Young from UCLA and Eric Rice from USC in the US, online social networking - and the topics discussed on these networks - have the potential to affect sexual risk behaviors. Targeting homeless youths with sexual health messages, by exploiting their use of these networks, is likely to be an effective way to reach and influence ...
2010-12-07
A brand-new bacterial species has been found aboard the RMS Titanic, which is contributing to its deterioration. The discovery reveals a potential new microbial threat to the exterior of ships and underwater metal structures such as oil rigs.
The researchers, who report their findings in the latest issue of the International Journal of Systematic and Evolutionary Microbiology published on 8 December, isolated the micro-organisms from a 'rusticle', collected from the RMS Titanic, 3.8 km below the ocean surface.
The novel bacterium has been named Halomonas titanicae by ...
2010-12-07
Researchers in South America have studied the viability of using earthworms to process hazardous material containing high concentrations of heavy metal for the bioremediation of old industrial sites, landfill and other potentially hazardous areas. They provide details of a possible approach in the International Journal of Global Environmental Issues this month.
After pollinating insects, worms are probably the gardener's best friend and they have been encouraged to process garden waste and soil for generations. The common earthworm, Eisenia fetida, could also become a ...
2010-12-07
A team led by scientists at the United Kingdom's National Oceanography Centre have measured the air-sea exchange of carbon dioxide in the open ocean at higher wind speed then anyone else has ever managed. Their findings are important for understanding how interactions between the oceans and the atmosphere influence climate.
"Evaluating the factors influencing the transfer of gases such as carbon dioxide between the atmosphere and the ocean is needed for a full understanding of Earth's climate system," explained researcher John Prytherch of the National Oceanography Centre.
The ...
2010-12-07
A well-known paper-based medical chart used by pediatric emergency personnel across America is undergoing a 21st century boost in an collaborative effort between Virginia Tech's College of Engineering, Roanoke-based Carilion Clinic Children's Hospital, and the physician who created the original method some 25 years ago.
The Broselow Pediatric Emergency Tape – otherwise known as the Broselow Tape -- has been a staple of ERs and child trauma units for nearly three decades. Created by Hickory, N.C.-based physician James Broselow, the Broselow Tape is a long, durable tape ...
LAST 30 PRESS RELEASES:
[Press-News.org] Study identifies drug resistance of CLL in bone marrow and lymph nodes
Potential mechanism identified