Peaches, skin and all, show promise in breast cancer fight, research finds

Chemicals found in peaches inhibit the growth of breast cancer cells and lessen the risk of the cancer spreading to other parts of the body, a Washington State University researcher has found.

Giuliana Noratto worked with colleagues at Texas A&M University for research on polyphenols, chemicals that are found in the flesh and skin of peaches.

Based on her research with mice, “I would eat three peaches a day,” including the skin, where polyphenols are concentrated, said Noratto, a WSU assistant professor of food science.

Just wash the peaches well to reduce any pesticide residue lingering on the skin, she said.

The study was published in the Journal of Nutritional Biochemistry. Noratto is the study’s lead author, with Texas A&M plant breeder David Byrne, food scientist Luis Cisneros-Zevallos and toxicologist Weston Porter.

Noratto, who did the peach study as part of her doctoral work, has a long-standing interest in the medicinal aspects of food. In her native Peru, many traditional foods are recognized for their antioxidant properties, she said.

Polyphenols are found in many fruits and vegetables. They have properties that help plants ward off harmful effects from the sun’s ultraviolet radiation, protecting DNA from the types of damage that cause cancer, Noratto said.

In earlier research at Texas A&M, Noratto and her colleagues published a study showing that peach and plum extracts suppressed the growth of breast cancer cells in petri dishes.

For the most recent study, breast cancer cells were implanted beneath the mice’s skin – a technique used for examining the growth of breast cancer cells in animals.

Mice that were fed high doses of the peach polyphenol had tumors that grew less, the research showed. They also had less of the blood vessel formation that helps cancer metastasize and spread to other parts of the body.

Researchers analyzed the mice’s lungs to check for tumors. They also looked for enzymes associated with cancer’s spread to other organs.

The reduction in the metastasis is significant, Noratto said. Researchers were using cells from an aggressive form of breast cancer, which doesn’t respond to hormone treatment.

Worldwide, breast cancer is a leading cause of death among women, Noratto said. The cancer travels around the circulatory system, invading distant organs and eventually causing death.

The research underscores diet’s role in reducing cancer risk, though only peach polyphenols have been linked to reduced metastasis at this point, Noratto said.

The amount of peach extract fed to the mice would translate into two to three peaches per day for a 132-pound woman. The fruit must be fresh, since heat destroys the polyphenols.

Noratto is also involved in research with whole wheat, berries and apples. Her work there focuses on whether those foods can reduce the chronic inflammation associated with obesity, which is also linked to cancer.

Noratto’s peach research was funded by Texas A&M’s Vegetable and Fruit Improvement Center and California Fruit Tree Agreement, a trade organization for peach, nectarine and plum growers.

Her goal is to build on the study with additional research involving mice and eventually secure a National Institutes of Health grant for clinical trials.