High cholesterol levels (search) may accelerate the growth of existing prostate cancer tumors (search), according to a new study.

Researchers say the results suggest that treating high cholesterol with cholesterol-lowering drugs like statins (search) may offer a new way to treat and potentially prevent prostate cancer.

"Our study opens up a new paradigm in thinking about how cancer might be controlled pharmacologically by manipulating cholesterol," says researcher Michael Freeman, PhD, program director of the urological diseases research center at Children’s Hospital Boston, in a news release. "Our data support the notion that cholesterol-lowering drugs -- which are widely used and fairly safe -- might be effective in prevention of prostate cancer, or as an adjunctive therapy."

The findings appear in the April 1 issue of The Journal of Clinical Investigation.

Cholesterol May Affect Prostate Cancer

In the study, researchers studied the effects of high cholesterol levels on prostate tumor growth in mice.

Mice were injected with human prostate cancer cells, and when the animals’ cholesterol levels were raised by diet, cholesterol accumulated in the outer walls of the tumor cells. This cholesterol buildup activated a “cell survival” pathway known as Akt.

Activation of this pathway prompted the tumor cells to resist cues to die. Therefore, the cancer cells multiplied and the tumors grew.

Researchers say elevated cholesterol levels did not stimulate new prostate cancers but promoted tumor growth.

In a separate experiment, researchers looked at the effects of adding a cholesterol-lowering statin drug to prostate cancer cells in a test tube. The drug reduced cholesterol buildup in the cell walls and increased the rate of cell death, which caused the cancer cells to stop growing.

Researchers say although some studies have linked high cholesterol levels to certain types of cancer, very little is known about the relationship between cholesterol and cancer at the cellular level. This study suggests that cholesterol may help prostate cancer tumors survive and grow at the cellular level by changing the chemical signaling pattern within the cells.

By Jennifer Warner, reviewed by Brunilda Nazario, MD

SOURCES: Zhuang, L. The Journal of Clinical Investigation, April 1, 2005; online advance edition. News release, Children’s Hospital Boston.