Quirks & Quarks

Doctors say blueberries can help radiation kill cervical cancer

Blueberry extract in conjunction with radiation therapy is effective in killing and stopping the spread of cervical cancer cells.
Extract from these blueberries provide a boost to cervical cancer therapy.

Blueberries proven to improve cervical cancer therapy in a lab experiment

Thousands of women around the world are diagnosed with cervical cancer every year, making it one of the most common types of the disease. Last year in Canada, that number was over 1,500, resulting in about 400 deaths. The traditional treatment, particularly in late stage cervical cancer, is radiation therapy. But radiation therapy comes with a problem. While it does destroy cancer cells, it also kills healthy cells in the vicinity. 

This dilemma inspired Dr. Yujiang Fang to find what he calls "a natural chemical with little or no side effect." Fang is an academic pathologist and assistant professor in the Department of Osteopathic Medicine at Des Moines University in Iowa, and an adjunct professor in the School of Medicine at the University of Missouri.   

Based on previous studies, including one by Fang as well as another at the University of Illinois in 2005 that demonstrated the effectiveness of red grapes as a radiosensitizer in killing prostate cancer cells, Yang and his colleagues called on the super food — blueberries. 

Radiosensitizers are non-toxic chemicals that help radiation target cancer cells. Fang says "we studied blueberry extract to see if it could be used a radiosensitizer."  This had not been studied before but blueberries seemed to be a good candidate because they contain two things that are very useful in killing cancer cells; one is resveratrol; the other is flavanoids. Resveratrol makes blueberries a good radiosensitizer; flavanoids are chemicals that give blueberries their famous antioxidant properties, but may also give blueberries anti-inflammatory and antibacterial properties. 

While antioxidants may sound too good to be true, there is a growing body of work that suggests a down side. A study conducted on mice in Sweden a few years ago found that antioxidants actually promote cell growth just as effectively as they inhibit cell growth.  His idea began with a large trial in the United States in the mid 1990's that found antioxidant supplements actually increased the risk of some cancers, especially lung cancer.   

While not at the clinical or even animal stage, Fang's experiment shows something different. The results of an in vitro human cervical cancer cell experiment were astounding. The cells were divided into four groups, a control group, a group that received only radiation treatment, a group that received only blueberries in extract form, and a fourth group that received a combination of radiation and blueberry extract.

70% decline in cancer cells with combo

Fang says "radiation decreased cancer cells by approximately 20 per cent. The cell group that received only blueberry extract had a 25 per cent decrease in cancer cells. However the biggest decline in cancer cells occurred in the radiation and extract group, with a decease of about 70 per cent."

There are two mechanisms that made this experiment a success. Blueberry extract in conjunction with radiation was able to control or keep down two molecules that are known to promote cancer cell growth. This is the radiosensitizer mechanism. The second mechanism was that blueberry extract again in conjunction with radiation was able to increase cell death outright. This is the flavanoids at work. 

The message he says is clear, and this is good news for cervical cancer patients down the road.  Although there is more research to be done before clinical trials can take place, the results are encouraging.   

Fang says he was pleased with the results, but not entirely surprised. Previously they successfully also experimented with extracts of broccoli, watermelon and pumpkin. Pumpkin seed extract has been studied for several years and has been found to be effective in killing lung cancer cells. 

Although these results are encouraging, they may at some point provide at least a boost to the treatment of cervical cancer therapy.