Low Cholesterol May Protect Against Aggressive Prostate Cancer
November 4, 2009
According to a prospective study of over 5,500 US men, epidemiologists say they now have evidence that having lower levels of heart-clogging fat may cut a man’s risk of developing high-grade prostate cancer, an aggressive form of the disease with a poorer prognosis. "For many reasons, we know that it’s good to have a cholesterol level within the normal range," says Elizabeth Platz, ScD, MPH, associate professor at the Johns Hopkins Bloomberg School of Public Health and co-director of the cancer prevention and control program at the Johns Hopkins Kimmel Cancer Center. "Now, we have more evidence that among the benefits of low cholesterol may be a lower risk for potentially deadly prostate cancers." Normal range is defined as less than 200 mg/dL (milligrams per deciliter of blood) of total cholesterol. Platz and her colleagues found similar results in a study first published in 2008, and in 2006, she linked use of cholesterol-lowering statin drugs to lower risk of advanced prostate cancer. For the current study, Platz, members of the Southwest Oncology Group, and other collaborators analyzed data from 5,586 men aged 55 and older. Men with cholesterol levels lower than 200 mg/dL had a 59 percent lower risk of developing high-grade prostate cancers, which tend to grow and spread rapidly. In Platz’s study, cholesterol levels had no significant effect on the entire spectrum of prostate cancer incidence, only those that were high-grade, she says. Platz cautions that results could have been affected by whether men in the study were taking cholesterol-lowering drugs at the time of the blood collections, a data point the researchers expect to analyze soon. "Cholesterol may affect cancer cells at a level where it influences key signaling pathways controlling cell survival," says Platz. "Cancer cells use these survival pathways to evade the normal cycle of cell life and death." She says that targeting cholesterol metabolism may be one route to treating and preventing the disease, but this remains to be tested.