Men who consumed a low-fat diet and fish oil capsules for 4 to 6 weeks before undergoing radical prostatectomy exhibited reduced prostate cancer (PCa) proliferation and lower ratios of omega-6 to omega-3 polyunsaturated fatty acids (PUFAs) in prostate tissue, in a recent study.
In their report for Cancer Prevention Research, William J. Aronson, MD, of the Jonsson Comprehensive Cancer Center at the University of California, Los Angeles, and co-investigators reported preclinical study findings that suggest lowering dietary fat and decreasing the ratio of omega-6 to omega-3 PUFAs reduces the risk of prostate cancer development and progression. Aronson’s team randomized 55 men scheduled for radical prostatectomy to a low-fat diet with 5 g of fish oil daily (representing a dietary omega-6 to omega-3 ratio of 2:1) or to a control Western diet (omega-6 to omega-3 ratio of 15:1) for 4 to 6 weeks before surgery.
Blood samples and prostate tissue from the 48 men who completed the trial revealed no differences between groups in terms of the primary end point, which was a change in serum insulin-like growth factor 1 (IGF-1). However, analysis for secondary outcomes demonstrated that the low-fat diet featuring fish-oil supplementation changed the membrane composition of both healthy cells and cancer cells in the prostate. The cell membranes had increased levels of omega-3 fatty acids and decreased levels of omega-6 fatty acids, and the tissues obtained from the radical prostatectomy specimens showed that this diet was associated with reduced levels of Ki-67, a protein involved in cancer cell progression and growth. ONA