What follows are some interesting works involving berries and cancer. Please note that while some of this is very interesting, it is a long way from being something that can be applied usefully today. These are very preliminary looks at things, and I put thm up on the blog to let people know some of the novel trains of thought people are pursuing. While it won’t hurt you to eat a ton of berries, and it certainly would be healthy, the evidence does not support a proven idea that you should suff yourself with these tasty fruits to do more than eat a nutritious food for your body. At this point in time whether there is any efficacy for them in relationship to cancer in humans is still a quuestion. But it’s, berry, berry interesting….. ( I can’t believe that I just typed that lame play on words.)
Dark fruits like blueberries, blackberries as well as papaya could be used to stop mouth cancer cells spreading through the rest of the body. They could also reduce the risk of mouth cancer, according to research published in the Journal of Cancer Research.
The study, carried out at the University of Hong Kong, found that as well as suppressing the spread of cancer, a substance called lupeol found in blueberries and other â€œsuper fruitâ€ also reduced the size of the tumour three times faster than conventional drugs. When the two were used together they were even more successful. The compound works by blocking a natural protein called NFkB which helps to grow and repair all cells â€“ even cancerous ones. Tests on mice also suggested that, unlike conventional drugs, lupeol would not cause the patient to lose weight.
Dr Nigel Carter, chief executive of the British Dental Health Foundation, said, â€œWe already knew a healthy diet, including at least five portions of fruit and vegetables each day, could reduce a personâ€™s risk of developing mouth cancer. â€œHowever the news that certain fruits might help to combat mouth cancer in people who have already developed the condition is a real revelation. â€œIt is true that this research is still in its early stages. However, the suggestion is the lupeol compound could be more effective than traditional drugs in preventing the growth of mouth cancer cells.â€
In anothger study, Ohio State University researchers found black raspberries may protect against esophageal cancer by reducing the oxidative stress that results from Barrett’s esophagus, a precancerous condition usually caused by gastroesophageal reflux disease. Reflux disease causes stomach acid to continually splash back up into the esophagus.
“Specifically in the case of Barrett’s patients, reflux of the stomach and bile acid contribute to ongoing oxidative damage. Thus, our hypothesis is that feeding a food that is high in potential protective constituents, such as antioxidants, vitamins, minerals and other phytochemicals, may help restore the oxidative balance,” lead researcher Laura Kresty said. People with Barrett’s esophagus typically are 30 to 40 times more likely to develop esophageal cancer, which has a poor five-year survival rate of 15 percent.
The team gave 32 grams to 45 grams of black raspberries daily for six months to 20 patients with Barrett’s esophagus. They analyzed changes in blood, urine and tissue before, during and after the treatment, and found lower levels of some of the chemical markers of oxidative stress in both urine and tissue samples. Black raspberries previously have been shown to reduce the risk of oral, esophageal and colon cancer in animal models, according to the researchers, who called for further study in humans.
Ohio has another take on berries as well. Gary Stoner, PhD, a scientist at the OSU Comprehensive Cancer Center â€“ James (OSU CCC-James) who has spent years conducting food-based cancer-prevention studies, says one serving should involve black raspberries, blackberries or strawberries. Stoner and colleagues have found that all three exhibit anticancer properties in rodents, but their more extensive studies have involved black raspberries. â€œBlack raspberries have high levels of anthocyanin pigments that give the berries their color and act as antioxidants to reduce cellular DNA damage caused by oxygen radicals and carcinogens in the body,â€ says Stoner. â€œThe more antioxidant activity, the more a berry can inhibit cancer.â€
Stonerâ€™s studies began in the 1980s when he examined ellagic acid, a compound that inhibits carcinogen-induced cancer in animals. Seeking natural sources of this compound, his team examined many fruits and found it most abundant in berries. They then began testing the berriesâ€™ ability to inhibit chemically induced esophageal and colon cancer in rodents. Collaborating with the OSU College of Food, Agricultural and Environmental Sciences, Stonerâ€™s team found that freeze-dried strawberries, black raspberries and blackberries, when added to the diets of rodents, prevented carcinogen-induced esophageal cancer by 60 percent compared with rodents on normal diets. They found that black raspberries inhibited carcinogen-induced adenocarcinoma in the colon of rodents by up to 80 percent.
At first they thought ellagic acid was principally responsible, but Stoner says they realize the inhibitory activity cannot be attributed to just one substance. â€œWe think other components, such as anthocyanins and other polyphenols, and the vitamins and minerals in berries, are also responsible,â€ he says. â€œNow we are trying to find out what natural compounds are the most effective cancer fighters.â€
In July 2003, he received a $2.7 million, five-year grant from the NCI to examine mechanisms by which freeze-dried black raspberries prevent cancer in rodent esophagus. â€œThe goals,â€ Stoner says, â€œare to better understand how berries block and suppress cancer activity and to develop a â€˜cocktailâ€™ of chemopreventive agents for preventing human esophageal squamous cell carcinoma.â€
The berry findings were presented at the International Conference on Frontiers in Cancer Prevention Research, being held in Philadelphia, Pennsylvania.The National Cancer Institute-funded trial included 30 participants, 20 of whom had identifiable precancerous lesions, and 10 normal controls. Each of the participants was instructed to gently dry the lesion sites (or a pre-selected control site for the normal participants) and rub the gel into the area four times a day, once after each meal and at bedtime.
After six weeks, about 35 percent of the trial participants’ lesions showed an improvement in their microscopic diagnosis, while another 45 percent showed that their lesions had stabilized. About 20 percent showed an increase in their lesional microscopic diagnoses. Importantly, none of the participants experienced any side effects from the gel. “The trial was designed to test the safety of the gel and detect any possible toxicity, but the next obvious step is a multicenter, double-blind, placebo-controlled Phase II study,” Mallery said. “Such a study would enable us to determine that the black raspberries are the active factor and not just the gel base or the act of drying and rubbing the lesions.”
The researchers also collected cell samples from the lesion sites of each participant before and after treatment in order to study the genetics and biology of the lesions. The majority of patients with precancerous lesions at the start of the trial showed elevated levels of COX-2 and iNOS, two proteins closely correlated with inflammation and malignant progression. Following treatment, Mallery says, levels of those proteins in the treated lesional epithelial cells decreased dramatically.
Mallery and her colleagues also examined samples for three tumor suppressor genes in order to determine what researchers call “loss of heterozygosity,” whether or not a cancer cell has lost one of its two copies of the gene. Such loss greatly increases a cell’s chances of losing the benefit of the tumor suppressor genes due to a second mutation or gene silencing event. Following the trial, the researchers noted that many lesions returned to normal, retaining both copies of each tumor suppressor gene. “We speculate that the chemopreventive compounds in black raspberries assist in modulating cell growth by promoting programmed cell death or terminal differentiation, two mechanisms that help “reeducate” precancerous cells,” Mallery said. “Oral cancer is a debilitating disease and there is a desperate need for early detection and management of precancerous lesions,” Mallery said. “While screening can help detect the disease early — and survival rates are definitely improved the earlier the disease is caught — many of these precancerous lesions recur despite complete surgical removal. There are currently no effective chemopreventive treatments which could conceivably serve as either adjunctive or alternative approaches to surgery.”
According to Mallery, the development of black raspberries as potential cancer-fighters is the result of decades of research into identification of naturally derived chemopreventive compounds by Ohio State researcher Gary D. Stoner, Ph.D., an emeritus professor at Ohio State University’s College of Medicine and Public Health. Clinical studies stemming from his research are currently underway for oral, esophageal and colorectal cancer.
The gel looks deceptively like black raspberry jam, but it certainly does not taste like something you would want to spread on toast, Mallery says. The bioadhesive gel, which contains 10 percent freeze dried black raspberries, is devoid of many of the tasty sugars found in native berries.
The black raspberry gel was manufactured by the University of Kentucky’s Good Manufacturing Production (GMP) facility. NanoMed Pharmaceuticals is partnering with OSU investigators Mallery, Stoner and Peter E. Larsen D.D.S. and Russell J. Mumper, Ph.D., of the University of North Carolina, in product development.