Chronic fatigue syndrome, cancer linked to new virus
A newly identified virus has been found to be linked to chronic fatigue syndrome and might also provide clues about how to prevent prostate cancer, according to a report this month in the journal Science. Called XMRV, the virus is transmitted in blood and body fluids and might be a significant public health threat.
Judy Mikovits, Ph.D., senior author of the paper, described the research during grand rounds at the University of Florida College of Medicine Thursday, Oct. 20. She was a guest of the division of hematology/oncology.
"This discovery opens a new area of medical possibilities for people who have a condition that has baffled doctors and researchers for years, and gives an insight into potential prevention and cures of cancer," Mikovits said.
Chronic fatigue syndrome is a multi-system disorder that is the subject of much controversy surrounding whether it is a true medical condition. Its cause is unknown and there are no diagnostic tests. It affects an estimated 17 million people worldwide.
Mikovits, who is research director at the Whittemore Peterson Institute in Nevada, and colleagues, found that 67 percent of 101 patients who had chronic fatigue syndrome also had the virus. In contrast, the virus was present in about 4 percent of 218 controls who did not have the syndrome.
XMRV, short for xenotropic murine leukemia virus-related virus, affects the immune system. It exists in blood and body fluids and is readily transmitted.
Chronic fatigue syndrome sufferers' relatives who had been diagnosed with neuroimmune diseases such as atypical multiple sclerosis, fibromyalgia and autism also tested positive for the virus, though these data were obtained after the publication and are still preliminary.
Sequences of the virus had previously been found in men who have prostate cancer. Mikovits also showed preliminary data that CFS patients in the study who subsequently developed cancer, primarily lymphoma, all tested positive for the XMRV.That raises the possibility that treating the virus could ultimately prevent many cancers, she said.
"It opens a new path for understanding the pathogenesis of cancer," said Carmen Allegra, M.D., chief of hematology/oncology at UF College of Medicine.
Researchers say the level of XMRV infection revealed in the study is not just a concern among people who have chronic fatigue syndrome, but is a public health issue as well.
"This is the discovery of a new virus that doesn't have any treatment, affects 4 percent of the population and has a transmission that seems to be easy," Allegra said.
Researchers continue to seek answers to many unanswered questions about the virus, including how it got into the human population, how it acts to cause disease and whether the virus alters the risk of cancer development in people who have chronic fatigue syndrome.
"There's quite a bit of work to do to understand the risk associated with this," said Nam Dang, M.D., Ph.D., deputy chief of hematology/oncology.