Categories
Cardiovascular
Diagnostics
Endocrinology
Health Insurance
Medical Devices
Mental Health
Nutrition
Oncology
Public Health
Sexual Health
Popular Articles

New Piece Found In Colorectal Cancer Puzzle
Prostasin, a relatively unknown protease enzyme expressed in most epithelial cells, may play a role in the genesis of colorectal cancer. Researchers writing in the open access journal BMC Cancer have associated a reduction in the expression of inhibitors of the enzyme with malignant cellular behavior.

Suspect In Murder Of Abortion Provider Tiller Sends Antiabortion Mailings From Jail
From his jail cell, Scott Roeder, the man charged in the murder of abortion provider George Tiller, has been sending inflammatory pamphlets calling such killings justifiable and corresponding with radical antiabortion-rights groups, the AP/Boston Globe reports. The pamphlets call Paul Hill, who was convicted of murdering abortion provider John Bayard Britton and his bodyguard in 1994, an "American hero" and quotes some of Hill"s writing about how murdering abortion providers is acceptable. Roeder obtained the pamphlets from the antiabortion-rights group Army of God. Roeder also has been corresponding with the Rev. Donald Spitz, founder of Army of God, and antiabortion-rights advocate Linda Wolfe, who has been jailed about 50 times for antiabortion activities and is a close friend of the woman convicted of shooting Tiller in the arms in 1993. The AP/Globe reports that the FBI and Department of Justice declined to comment on whether they are concerned about Roeder"s mailings. Last month, Roeder in an interview said that there are "many other similar events planned around the country as long as abortion remains legal." Roeder has not been accused of breaking any laws because of the correspondence (AP/Boston Globe, 7/4).
News of the day
Unique Collaboration Between TB Alliance And Tibotec To Accelerate Tuberculosis Drug Development
A new landmark collaboration between the Global Alliance for TB Drug Development (TB Alliance), a not-for-profit, product development partnership, and Tibotec Inc., (Tibotec), a global pharmaceutical company, has been announced at the Pacific Health Summit in response to the urgent need to accelerate the discovery and development of new drugs to fight tuberculosis (TB).
Endocrinology

Gliomas Exploit Immune Cells Of The Brain For Rapid Expansion

Gliomas are among the most common and most malignant brain tumors. These tumors infiltrate normal brain tissue and grow very rapidly. As a result, surgery can never completely remove the tumor. Now, the neurosurgeons Dr. Darko S. Markovic (Helios Klinikum Berlin-Buch) and Dr. Michael Synowitz (Charité) as well as Dr. Rainer Glass and Professor Helmut Kettenmann (both Max DelbrÃøck Center for Molecular Medicine, MDC, Berlin-Buch), have been able to show that glioma cells exploit microglia, the immune cells of the brain, for their expansion (PNAS Early Edition)*. Microglial cells are the immune cells of the brain/central nervous system. They constantly screen the brain environment. On their surface they use sensors to detect changes in their environment due to brain damage or infections. An important family of these sensors are Toll-like receptors (TLR). However, microglia do not attack glioma cells. On the contrary: they support the growth of the tumor and, thus, make the disease worse. Together with researchers in Warsaw, Poland, Amsterdam, The Netherlands, and Bethesda, USA, the researchers in Berlin have been able to show how the immune cells promote the tumor growth. Microglial cells are attracted toward the glioma cells and gather in and around the tumor in large numbers. Interestingly, gliomas consist of up to 30 per cent of microglia, especially at the tumor edge. Gliomas release certain enzymes, metalloproteases, which digest the extracellular matrix, and also dissolve the ties between cells. However, the metalloproteases are produced and released as inactive precursor protein which need to be cleaved to be activated. This cleavage is accomplished by another enzyme, which is produced by the microglial cells. This enzyme is anchored in the membrane and was therefore named membrane type 1 metalloprotease (MT1-MMP). MT1-MMP activates the metalloproteases which clear the way for the glioma cells and allows them to infiltrate normal brain tissue and expand very rapidly. Normally, microglial cells do not produce MT1-MMP. However, the glioma cells manipulate the microglial cells by stimulating microglial TLR which trigger the expression of MT1-MMP. The researchers could confirm their data from petri dish in mice. "Those mice, in which we had knocked out the MT1-MMP gene or a crucial gene for TLR signalling, did attract fewer microglial cells and the tumor grew much more slowly", explains Professor Kettenmann. They could also demonstrate that MT1-MMP was present in tissue from glioma patients. Remarkably, the gliomas with high level of microglial MT1-MMP were also more aggressive. Moreover microglial cells were more abundant in tissue sample from the tumor edge as compared to the center of the tumor. Glioma cells themselves do not produce MT1-MMP. However, when the researchers experimentally over expressed MT1-MMP in glioma cells, they died. The researchers hope, that interfering with TLR receptors or their intracellular pathways might reduce the rapid expansion of glioma cells. Professor Kettenmann: "Microglia are a new target for glioma researchers." * Gliomas induce and exploit microglial MT1-MMP expression for tumor expansion D. S. Markovica,b, K. Vinnakotaa, S. Chirasania, M. Synowitza,c, H. Ragueta, K. Stocka, M. Sliwad, S. Lehmanne, R. Ka¨ linf,N. van Rooijeng, K. Holmbeckh, F. L. Heppnerf, J. Kiwitb, V. Matyasha, S. Lehnardte, B. Kaminskad, R. Glassa,1,2, and H. Kettenmanna,1 aCellular Neuroscience, Max DelbrÃøck Center for Molecular Medicine, 13125 Berlin, Germany; bDepartment of Neurosurgery, Helios Clinics, 13125 Berlin, Germany; cDepartments of Neurosurgery and fNeuropathology and eCecilie Vogt Clinic for Neurology, Charité - Universitätsmedizin Berlin, 13353 Berlin, Germany; dLaboratory of Transcription Regulation, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland; gDepartment of Molecular Cell Biology, Faculty of Medicine, Vrije Universiteit, VU University Medical Center, 1081 BT Amsterdam, The Netherlands; and hCraniofacial Skeletal Diseases Branch, Matrix Metalloproteinase Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892 Barbara Bachtler Helmholtz Association of German Research Centres


Add your comment:
Name:
Site address: http://
Your message:
Enter today\\\\'s date, 2 digits
(spam protection):

© Copyright 2009