Washington: Compounds found in purple potatoes may help kill colon cancer stem cells and limit the spread of the cancer, Indian-origin scientists have found.
Baked purple-fleshed potatoes suppressed the growth of colon cancer tumours in petri dishes and in mice by targeting the cancer’s stem cells, researchers have found. Attacking stem cells is an effective way to counter cancer, according to Jairam K P Vanamala, associate professor of food sciences at the Pennsylvania State University. The researchers used a baked purple potato because potatoes are widely consumed and typically baked before they are consumed, especially in western countries. They wanted to make sure the vegetables maintained their anti-cancer properties even after cooking. In the initial laboratory study, researchers found that the baked potato extract suppressed the spread of colon cancer stem cells while increasing their deaths.
Researchers then tested the effect of whole baked purple potatoes on mice with colon cancer and found similar results. The researchers used baked purple potato because they wanted to make sure the vegetables maintained their anti-cancer properties even after cooking. The portion size for a human would be about the same as eating a medium size purple-fleshed potato for lunch and dinner, or one large purple-fleshed potato per day. According to the researchers, there may be several substances in purple potatoes that work simultaneously on multiple pathways to help kill the colon cancer stem cells, including anthocyanins and chlorogenic acid, and resistant starch.
“Our earlier work and other research studies suggest that potatoes, including purple potatoes, contain resistant starch, which serves as a food for the gut bacteria, that the bacteria can covert to beneficial short-chain fatty acids such as butyric acid,” Vanamala said. “The butyric acid regulates immune function in the gut, suppresses chronic inflammation and may also help to cause cancer cells to self-destruct,” Vanamala said.
In addition to resistant starch, the same colour compounds that give potatoes, as well as other fruits and vegetables, a rainbow of vibrant colours may be effective in suppressing cancer growth, he added. The next step would be to test the whole food approach using purple potatoes in humans for disease prevention and treatment strategies. The researchers also plan to test the purple potatoes on other forms of cancer.
Vanamala worked with Venkata Charepalli, a doctoral student; Sridhar Radhakrishnan, a post-doctoral scholar; Ramakrishna Vadde, a visiting scientist from India, all in food science and Lavanaya Reddivari, assistant professor of plant science, all from Penn State and Rajesh Agarwal, professor of pharmaceutical science, University of Colorado. The study was published in the Journal of Nutritional Biochemistry.
