High blood cholesterol can make prostate tumors grow faster, researchers said on Thursday in another study linking high-fat diets with prostate cancer.
The tests in mice did not suggest that high cholesterol actually causes cancer, but did show that higher levels of the blood fats fueled prostate cancer growth, the researchers said.
“What we’re looking at is progression, not initiation, of a tumor,” said Michael Freeman of Children’s Hospital Boston, who led the study.
Writing in the Journal of Clinical Investigation, Freeman’s team said it also found evidence that cholesterol-lowering statin drugs can interfere with tumor growth.
They injected human prostate cancer cells into mice and watched as the tumors grew — not a perfect model of human cancer, but one widely used in cancer research.
When they fed the mice a high-cholesterol diet, cholesterol accumulated in the outer membranes of the tumor cells, Freeman’s team said.
Anti-cholesterol drugs may help
This in turn activated a chemical cell-survival process known as Akt, which scientists believe is a central pathway in prostate cancer. The tumor cells then resisted chemical cues to self-destruct through the process known as apoptosis or cell suicide, and they instead proliferated.
A second study in lab dishes showed that when the cholesterol-lowering drug simvastatin was used to reduce cholesterol in cell membranes, the tumors stopped proliferating.
“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,” Freeman said.
Prostate cancer is by far the most common cancer among U.S. men, and will affect 232,090 men this year and kill 30,350, according to American Cancer Society predictions.
