LOS ANGELES CA (EMBARGOED until July 25, 2003) In an article appearing in a special issue of the Journal of Neuro-oncology, researchers at Cedars-Sinai Medical Center's Maxine Dunitz Neurosurgical Institute describe a complex cell-level process that allows malignant brain tumors to protect themselves by damaging the thymus, rapidly degrading the immune system. In a second article, Institute scientists identify a molecular mechanism that causes cell death of cancer-fighting lymphocytes as they infiltrate a brain tumor. The special edition will be published July 25, 2003.
"We are dissecting and better understanding the mechanisms that enable tumors to evade destruction by the immune system. This gives us new tools in our fight against brain cancer, to essentially correct these deficits and further enhance the ability of the immune system, not only to detect but also to destroy brain tumors," said Keith L. Black, M.D., director of the Institute, Cedars-Sinai's Division of Neurosurgery and the Comprehensive Brain Tumor Program.
In an animal study, researchers found that intracranial gliomas aggressive brain tumors damage the thymus, the gland responsible for the development and potency of the immune system's T cells. As the thymus shrinks and its normal structure becomes distorted, many of the thymocytes the "immature" cells destined to become functional T cells potentially capable of destroying a variety of antigens undergo a process that weakens and kills them.
Thymocytes are derived from bone marrow and as they travel through the thymus they go through a natural selection process that removes the weakest and prepares the strongest to become lymphocytes that can later adapt as needed to meet a variety of immune challenges. When an intracranial glioma is present, the researchers found, the number of healthy T cells leaving the thymus is dramatically reduced, preventing a large-scale attack on the tumor.
Changes to the thymus and "rePage: 1 2 3 4 Related medicine news :1
Contact: Sandra Van
Cedars-Sinai Medical Center
. Cedars-Sinai medical tipsheet for Dec. 20042
. Cedars-Sinai October 2004 medical tipsheet3
. Cedars-Sinai Medical tipsheet for May 20044
. Cedars-Sinai receives full AAHRPP accreditation for all research involving human subjects5
. Cedars-Sinai March medical tipsheet6
. Cedars-Sinai researchers identify a gene that causes insulin resistance in Mexican Americans7
. Medical geneticist at Cedars-Sinai awarded $8.5 million NIH research grant8
. Cedars-Sinai Medical tipsheet for July 20039
. Cedars-Sinai researchers to present findings at Amerian College of Cardiology Scientific Meeting10
. Patients who need cardiac resynchronization therapy may be eligible for Cedars-Sinai clinical trials11
. Study at Cedars-Sinai Medical Center investigates effectiveness of two popular dietary supplements to improve symptoms of osteoarthritis