New studies published in the British Journal of Cancer
suggest that, in mice at least, consumption of a diet enhanced with fish
oil helped a chemotherapy drug to work more effectively against and also
reduced intestinal damage caused by the drug.
The Health Science Center researchers, W. Elaine
Hardman, Ph.D., Mary Pat Moyer, Ph.D., and Ivan Cameron, Ph.D., noted
significantly increased tumor regression in mice receiving fish
oil-enhanced diets. The findings are so promising, Dr. Hardman said, that
the researchers have proposed a clinical trial in humans to the National
Cancer Institute. The chemotherapy drug in the study was CPT-11 (irinotecan).
Dr. Hardman, research assistant professor in the
Department of Cellular and Structural Biology, and Dr. Cameron, professor
of cellular and structural biology, compared groups of mice on normal
diets and fish oil-added diets. The fish oil-supplemented group of mice
received a low dose of specially processed omega-3 fatty acids (fish oil),
equivalent to a human consumption of 10 to 12 grams of fish oil per day.
“While the chemotherapy stopped growth of the
implanted breast cancers in mice eating a normal diet, in those mice
eating a fish oil-added diet the tumors were significantly reduced and the
intestinal damage caused by CPT-11 was ameliorated,” Dr. Hardman said.
Salmon, striped bass, swordfish and tuna are rich
sources of omega-3 fatty acids, and scientists previously have shown these
fatty acids slow or prevent tumor growth. The new study is one of the
first to show the impact of fish oil on the effectiveness of cancer
chemotherapy, however. Walnuts, soybeans, canola oil and flaxseed are
other less-concentrated sources of omega-3 fatty acids.
Dr. Hardman emphasized that the tumor regression
findings were based on use of specially processed and formulated omega-3
fatty acids, and cannot be extrapolated to consumption of currently
available fish oil products.