Grape seed can aid the effectiveness of chemotherapy in killing colon cancer cells as well as reducing chemotherapy side effects, according to new research. Combining grape seed extracts with chemotherapy has potential as a new approach for colon cancer treatment—both to reduce intestinal damage commonly caused by cancer chemotherapy and to enhance its effect.
Lead author Amy Cheah, PhD, of the University of Adelaide in South Australia, explained that there is a growing body of evidence about the antioxidant health benefits of grape seed tannins or polyphenols as anti-inflammatory agents and, more recently, for their anticancer properties.
“This is the first study showing that grape seed can enhance the potency of one of the major chemotherapy drugs in its action against colon cancer cells,” said Cheah. This study was published in PLOS ONE (2014; doi:10.1371/journal.pone.0085184).
“Our research also showed that, in laboratory studies, grape seed taken orally significantly reduced inflammation and tissue damage caused by chemotherapy in the small intestine, and had no harmful effects on noncancerous cells. Unlike chemotherapy, grape seed appears to selectively act on cancer cells and leave healthy cells almost unaffected,” said Cheah.
The researchers used commercially available grape seed extract, a byproduct of winemaking. Tannins extracted from the grape seed were freeze-dried and powdered. The extract was tested in laboratory studies using colon cancer cells grown in culture.
The research found that grape seed extract had no side effects on the healthy intestine at concentrations of up to 1,000 mg/kg. It significantly decreased intestinal damage compared with the chemotherapy control, and it decreased chemotherapy-induced inflammation by up to 55%. It also increased growth-inhibitory effects of chemotherapy on colon cancer cells in culture by 26%.
“Our experimental studies have shown that grape seed extract reduced chemotherapy-induced inflammation and damage and helped protect healthy cells in the gastrointestinal tract,” said Dr. Cheah. “While this effect is very promising, we were initially concerned that grape seed could reduce the effectiveness of the chemotherapy.”
“In contrast, we found that grape seed extract not only aided the ability of chemotherapy to kill cancer cells, but was also more potent than the chemotherapy we tested at one concentration,” Cheah added.
Coauthor and project leader Gordon Howarth, PhD, said, “Grape seed is showing great potential as an anti-inflammatory treatment for a range of bowel diseases and now as a possible anticancer treatment. These first anticancer results are from cell culture and the next step will be to investigate more widely.”