Researchers report that antibodies responsible for a disease called systemic lupus may make some cancers more sensitive to treatment.
Lupus is an autoimmune disease. In this type of disorder, the immune system gets confused and instead of protecting the body against bacteria and viruses, misguided antibodies attack healthy cells and organs, including the heart, kidneys, intestines, brain and skin. Lupus can be a fatal condition.
But ironically, there might also be a benefit to having lupus. For reasons scientists are just beginning to understand, about one-third fewer people with lupus develop cancer of the breast, ovaries and prostate compared to the general population. Researchers have discovered that an immune-system antibody produced by lupus patients, called 3E10, seems to sensitize cancer cells for destruction when used in conjunction with radiation treatments.
Peter Glazer is a professor of therapeutic radiology and genetics at Yale University School of Medicine in New Haven, Connecticut. He's part of a research team studying 3E10. Glazer says lupus antibodies, isolated from experimental mice, easily penetrate cancer cells, as well as normal ones.
“We speculate that perhaps the anti-cancer properties that we’ve identified in this one particular lupus antibody might be found or similar properties found in antibodies that lupus patients have," said Glazer.
Glazer says 3E10 appears to be harmless to benign or healthy cells. But in cancerous cells, the antibody interferes with the genetic repair mechanism. That means the cells can't fix broken DNA strands, leaving them more vulnerable to assaults by chemotherapy and radiation.
“And in that setting, the antibody was effective in killing the cancer cells all by itself," he said.
Glazer says researchers working with mouse models of lupus antibodies also found that they could kill defective cells associated with a type of breast cancer, as well as some ovarian and prostate cancers, without the need for chemotherapy or radiation.
Scientists say the discovery could lead to important insights into lupus, a disease that afflicts more than five million patients around the world. It also suggests that lupus antibodies - which have already been used safely in clinical trials of a possible lupus vaccine - could provide new and more effective forms of treatment for a variety of cancers.
An article on the potential therapy using a lupus antibody to fight cancer is published in the journal Science Translational Medicine.