Fish Oils Reduce Size of Cancer Tumors

The omega-3 essential fatty acid known as docosahexaenoic acid (DHA) is more effective at reducing the size of breast cancer tumors than the chemotherapy drug cisplatin, and can also reduce that drug's harmful side effects, reports a new study published in the journal Cell Division.

"Our results suggest a new, fruitful drug regimen in the management of solid tumors based on combining cisplatin and possibly other chemotherapeutics with DHA," said researcher A.M. El-Mowafy of Egypt's Mansoura University. "DHA elicited prominent chemo-preventative effects on its own, and appreciably augmented those of cisplatin as well. Furthermore, this study is the first to reveal that DHA can obliterate lethal cisplatin-induced nephrotoxicity [kidney damage] and renal tissue injury."

Researchers injected a group of mice with breast cancer cells, then treated them with either 125 or 250 milligrams per kilogram of DHA, a regular dose of cisplatin, a mix of cisplatin and 125 milligrams per kilogram of DHA, or a placebo. They recorded tumor size and blood levels of white blood cells, C-reactive protein (CRP) and MDA at the start of the study and again after 20 days.

CRP is a marker of inflammation, a known risk factor for tumor growth. MDA is a marker of lipid peroxidation, which signifies high levels of the free radicals that can lead to cancer. Elevated white blood cell counts are also associated with tumor growth.

The researchers found that compared with mice that had never been injected with cancer cells, the injected mice underwent a significant increase in levels of CRP, MDA and white blood cells. Elevated levels of CRP and white blood cells were significantly correlated with increased tumor size.

Levels of white blood cells, CRP and MDA were all lower in animals that had been treated with either DHA, cisplatin, or a combination, however.

In animals who received 125 milligrams per kilogram of DHA, tumor growth was 38 percent less than in animals who received a placebo. Animals receiving cisplatin had 55 percent less tumor growth, while those treated with 250 milligrams per kilogram of DHA had 79 percent less. The combination of DHA and cisplatin not only reduced tumor growth by 81 percent compared with a placebo, it also returned white blood cell counts to normal levels. The 250 milligram per kilogram dose of DHA was nearly as effective at restoring a normal white blood cell count as the DHA-cisplatin combination.

"The chemoprevention elicited by DHA was dose-dependent, and appeared to be mediated by reduction of leukocytosis [elevated white blood cell count], oxidative stress, and replenishing of endogenous antioxidant machinery," the researchers wrote. "Most strikingly, a strong anti-inflammatory effect was produced."

In a second experiment, researchers treated rats with cisplatin, which is known to produce potentially lethal kidney damage. Half the rats were also given a 250 milligram per kilogram dose of DHA, while the other half was given nothing.

All the rats that received only cisplatin died from kidney toxicity. Among animals given both the drug and the omega-3, however, only 12 percent developed lethal kidney damage.

DHA is found primarily in fatty cold-water fish, such as salmon, anchovies, herring, mackerel and sardines, but it can also be found in certain vegetable oils. It is believed to play a critical role in the development of the nervous system, particularly the brain and retina. -naturalnews