Gene therapy protocol at UCSD activates immune system in patients with leukemiaFebruary 12, 2008A research team at the Moores Cancer Center at University of California, San Diego (UCSD) reports that patients with chronic lymphocytic leukemia (CLL) who were treated with a gene therapy protocol began making antibodies that reacted against their own leukemia cells. The study will be published on line the week of February 11-15 in the online edition of the Proceedings of the National Academy of Science. Researchers led by Thomas J. Kipps, M.D., Ph.D., inserted a gene with the potential to activate an immune response - a gene therapy protocol developed at UCSD - into six patients with CLL, the most common form of adult leukemia. Several of the patients started making antibodies that reacted against their own leukemia cells. When tested in the lab, the antibodies also reacted with the leukemia cells of other patients with the disease. "The patient's own leukemia cells were modified outside of their body and given back as a vaccine," said Kipps. "The result raises hope that it may be possible to activate a patient's immune system against their own cancer."
The patients were shown to make antibodies reactive with a leukemia-associated antigen - a protein made by leukemia cells that can stimulate the body's immune system to produce antibodies - called ROR1. This antigen appears to be found only on the cell surface of the leukemia cells, but not on normal cells, and serves as a receptor that binds to a ligand called Wnt5a, which activates a pathway important for the survival of the leukemia cells. "The Wnt5a ligand interacts with ROR1 to enhance leukemia-cell survival. Antibodies that react with ROR1 can interfere with this survival signal and might also specifically target the leukemia cells for destruction," Kipps said. He also noted that because the ROR1 antigen is found only on leukemia cells, it could be developed as a very specific marker to monitor for the continued presence of leukemia cells after treatment or for identifying leukemia cells in patients with early disease, when the cancer otherwise might not be detected. It also provides a much more specific target for antibody therapy. Antibodies that target ROR1 would be unlike currently used antibodies, which bind antigens found not only on leukemia cells, but also on normal cells. Because they can destroy normal cells, the antibodies currently used to treat patients with this leukemia can cause side-effects and weaken the immune system. The ROR1 antigen is ordinarily found on a few cells in early embryonic development and is not detected on adult human cells or tissues. However, high amounts of this antigen are found on all the leukemia cells of patients with CLL. In the PNAS paper, the UCSD researchers present data on the leukemia cells of approximately 70 patients, all of which expressed the ROR1 antigen. University of California - San Diego | |||||||||||||||||||||
|
Related Leukemia Current Events and Leukemia News Articles Hodgkin lymphoma -- new characteristics discovered Researchers are still discovering new characteristics of Hodgkin lymphoma, a common form of cancer of the lymphatic system. The malignant cells are derived from white blood cells (B cells), but have lost a considerable part of the B cell-specific gene expression pattern. Anti-cancer drug prevents, reverses cardiovascular damage in mouse model of premature aging disorder An experimental anti-cancer drug can prevent -- and even reverse -- potentially fatal cardiovascular damage in a mouse model of progeria, a rare genetic disorder that causes the most dramatic form of human premature aging, National Institutes of Health (NIH) researchers reported today. New research to help dogs with cancer may benefit people A new study jointly conducted by Oregon State University College of Veterinary Medicine and the Oregon Health & Science University Cancer Institute may one day help not only our canine friends with cancer, but also people with the human form of the disease. Embryonic stem cells might help reduce transplantation rejection Researchers have shown that immune-defense cells influenced by embryonic stem cell-derived cells can help prevent the rejection of hearts transplanted into mice, all without the use of immunosuppressive drugs. VCU Massey Cancer Center Spearheads Novel Clinical Study for Lymphoma Patients The Virginia Commonwealth University Massey Cancer Center recently opened a National Cancer Institute (NCI)-sponsored, phase II clinical study for certain sub-types of non-Hodgkin's lymphoma. New insights into the regulation of PTEN tumor suppression function The PTEN tumor suppressor gene controls numerous biological processes including cell proliferation, cell growth and death. But PTEN is frequently lost or mutated; in fact, alteration of the gene is so common among various types of human cancer that PTEN has become one of the most frequently mutated of all tumor suppressors. Children's national co-leads nationwide study of landmark sickle cell treatment Children's National Medical Center immunologist and blood and marrow transplant physician Naynesh Kamani, MD, will serve as the study co-chair for a new national clinical trial of unrelated donor marrow and umbilical cord blood transplants for severe sickle cell disease. Newly discovered molecular switch helps decide cell type in early embryo development Researchers have discovered a central molecular switch in fruit fly embryos that opens new avenues for studying the causes of birth defects and cancer in humans. Writing about their study in the Aug. 12 Developmental Cell, scientists at Cincinnati Children's Hospital Medical Center determined the switch to be a main tuning mechanism for instructing cells whether to form sensory nerves or blood cells in different parts of the body. McGill researchers overcome chemotherapy resistance in the lab Researchers from McGill University's Faculty of Medicine have discovered a compound that reduces resistance to chemotherapy agents used to treat cancer. Their results were published in the June issue of The Journal of Clinical Investigation (JCI). Crucial Factors in Lymphoma Development and Survival Discovered Researchers at National Jewish Medical and Research Center have discovered an important factor in the development of B-cell lymphomas, one of the fastest growing forms of cancer. More Leukemia Current Events and Leukemia News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||