By Jennifer Warner
March 31 (CBSHealthWatch)—A new, experimental treatment may one day allow cancer patients to give themselves the immune boost their bodies need to ward off cancer cells. For the first time, researchers say they have found a way to increase the number and effectiveness of a rare and powerful type of immune system cells within the human body—a process once only possible in a laboratory.
The study conducted at the University of California at Los Angeles’ Jonsson Cancer Center found injections of two immune system hormones effectively “switched on” the immune systems in patients whose immune systems had been turned off by cancer. Researchers say the discovery is a major step toward making cancer vaccine therapies more patient-friendly and less expensive.
“This is a home therapy,” says the study’s lead author, Dr. Michael Roth, associate professor of medicine at UCLA. “They are once-a-day injections that the patients give themselves pretty much the same way as they take an insulin injection.”
Previous cancer vaccine methods entailed labor intensive laboratory procedures and required large amounts of blood to be drawn, treated and then re-injected into the patients in a hospital setting.
The new technique involves re-activating dendritic cells, which are thought to be the key cells in the body that stimulate the immune system’s attack on abnormal molecules in the body from such invaders such as bacteria, viruses and allergens. But for some reason the cells do not work against cancer. Scientists believe cancers trick the immune system and prevent the dendritic cells from launching their attack.
“Cancer has circumvented the immune system, partly because cancer is your own ‘normal’ cells, so there are many ways that it can fool the immune system,” says T. J. Koerner, PhD, scientific program director at the American Cancer Society. “It offers a great promise to be able to have your own body develop a robust immunity to the cancer.”
Patients who received the new therapy had a 100-fold increase in the number of dendritic cells. Researchers say that means the patients may have enough cells to stimulate their immune systems to fight some types of cancer, but some may need additional treatment.
“A second step for some cancers may be you’d need to actually vaccinate the patient, which is a way of directing the immune system against a specific tumor,” says Roth.
The study is published in the April 1 issue of the journal Cancer
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