A study on black raspberries and mouth tumors on experimental animals revealed that these berries can inhibit oral cancer, reported an article in the American Institute for Cancer Research website. The researchers also discovered cancer-related genes that could help explain its actions.
Dr. Steve Oghumu, Ph.D., the lead author of the study and a scientist at the Ohio State University, said their findings showed how feeding black raspberries to rats helped prevent the development of oral cancer in the animal models.
Black raspberries are slightly sweet berries endemic to North America. The berries are full of fiber and vitamins. Black raspberries also have plant-based compounds called phytochemicals.
The Oral Cancer Foundation posited that at least 50,000 people in the U.S. would be diagnosed with oral cancer in 2016, about 10,000 of which would die from the disease. Oral cancer is common among individuals who drink alcohol or smoke tobacco.
Based on data from preclinical and clinical trials in humans, black raspberries can help prevent or slow the development of oral cancers. However, not much is known about the molecular basis for the berries’ health benefits. (Related: Oral Cancer May be Treated with Proanthocyanidins from Medicinal Plants.)
Earlier studies established crucial cancer-related genes in humans that were “switched on or off” once black raspberries were consumed. Dr. Oghumu explained that the study’s goal was to confirm if those same genes were regulated in the rat model and if the same effects were replicated.
For the study, the researchers assigned the rats with oral cancer to three dietary groups for 16 weeks. The first group followed a standard diet, the second followed a diet with five percent freeze-dried black raspberries, and the third group followed a diet with 10 percent black raspberries. A comparison group of rats was cancer-free.
After the study period, the researchers examined the rats’ tongue and blood for markers linked to inflammation and apoptosis (cell death). Among the animals that consumed the black raspberries, markers of apoptosis indicated signs of promoting cancer cell death. Markers of inflammation were also reduced compared to the rats on the standard diet.
The black raspberries also affected the number of tumors on the rats’ tongues. In the rats that followed the diet with five or 10 percent black raspberries, tumors were reduced by 39 and 29 percent, respectively, compared to the rats on the standard diet.
Dr. Oghumu noted that the results were shocking, especially since they weren’t expecting the lower concentration of black raspberries to be more potent. He added that this whole food approach, which has few risks, can prevent oral cancer. It is also feasible since the berries are easily available.
Dr. Oghumu concluded that their research is notable since it helped determine that black raspberries can inhibit carcinogenesis in a rat model. It also identified a suitable animal model that can help experts discover how black raspberries inhibit oral cancer in humans.