Tea is the second most consumed beverage in the world and is filled with antioxidants.
Researchers across the country and at Feist-Weiller Cancer Center, part of the LSU Health Science Center in Shreveport, believe green tea may be more than just an antioxidant and they're attempting to prove these claims in the laboratory.
Dr. James Cardelli, professor of microbiology and immunology and director of research at FWCC, believes that green tea could hold an answer in future cancer treatment, but perhaps not in its whole form.
Instead, FWCC research points to a particularly notable component of tea called epigallocatechin-3-gallate (EGCG), and their research with this agent has been extended to clinical trails, ongoing and planned in the near future.
It's time for traditional medicine to think outside the box, says Cardelli, but there's a lot of misinformation associated with nontraditional treatments.
"The public is kind of confused, and in an understandable way," he said.
Tea, like many fruits and vegetables, have antioxidant properties, allowing the body to scavenge for free radicals -- nasty by-products from the chemical reactions that occur in the body. But many health claims, largely antidotal and based on epidemiological studies, say green tea can do much more: It's anti-inflammatory, anti-viral and anti-bacterial, it prevents high blood pressure, helps you lose weight and reduces the risk of certain types of cancer.
"My role as a scientist is to try to take the spin out; basically we're separating fact from fiction. What works and what doesn't work in accepted scientific models and clinical trials," Cardelli said.
One misunderstood claim was answered by the Food and Drug Administration in 2005 in response to a bid by Dr. Lee's TeaForHealth, a tea company, to label products with cancer-prevention health claims may have added to the public's confusion. What the FDA concluded was that green tea is highly unlikely to reduce the risk of breast and prostate cancer, and that it did not support health claims at all for green tea consumption and other cancers.
"What the FDA was basically talking about is the green tea people go out and drink," Cardelli said. "It's not the green tea, it's the agents in green tea."
From the beaker to patients
Green tea stands above other teas because it's the least processed and provides the most tea catechins. EGCG is the most active of tea catechins, which are antioxidants and may be loosely classified as polyphenols.
After three years of examining green tea polyphenols, researchers at Feist-Weiller Cancer Center, headed by Cardelli, extended their research by initiating a Phase II clinical trial a year ago, using the concentrated capsule form of EGCG that also contains three other green tea polyphenols (Polyphenon E).
Drs. Donald Elmajian, Benjamin Li, Jerry McLarty, Gary Burton and Quyen Chu are participating in a trial that combines the skills of both basic scientists and clinical scientists.
The trial has recruited more than 20 cancer patients, both prostate and breast. Patients with prostate cancer orally take 800 milligrams of EGCG in capsule form daily -- the equivalent of drinking 12 typically brewed cups of tea -- for five to six weeks prior to having their cancer tumor resected.
"We are measuring biological markers that predict the progression of prostate (and breast) cancer cells," he said. "What we are seeing is significant decreases in the levels of some of these markers."
For prostate cancer, researchers use the prostate-specific antigen (PSA) test to monitor the disease in men.
"That's one thing we're measuring," Cardelli said. "In the patients that we've treated, the PSA appears to be falling, although this does not mean the tumor is shrinking. Although preliminary, the results are positive and we'll probably expand the trial."
For researchers, exactly what EGCG does to tumor cells is still part mystery.
"We know these agents are great antioxidants, but they do lots of other things," said Cardelli. "They clearly react with tumor cells and they seem to slow proliferation, increase cell death and reduce tumor invasion. Most of these agents appear to work independently of their function as an antioxidant."
The National Cancer Institute funded a clinical trial with 42 prostate cancer patients and the consumption of about four cups of green tea daily for four months. The NCI concluded that drinking green tea has limited benefits. Several patients also suffered side effects such as nausea and diarrhea.
Cardelli said the trial had many problems that have been eliminated.
"The patients are already dying from advance prostate cancer (in this trial), and it is unlikely any chemical could help. Also, four cups of green tea is probably not enough and the side effects are most likely due to the caffeine in the green tea," Cardelli said. "Our patients have suffered no side effects for up to three months, and there is no caffeine in the capsules containing green tea polyphenols."
Also looking at EGCG is the Mayo Clinic in Rochester, Minn., a Comprehensive Cancer Center designated by the National Cancer Institute, which has an open Phase I clinical trial with chronic lymphocytic leukemia patients. This is the first for CLL patients and is unique in that a patient group has sponsored and funded the trial.
A topics thread by CLL patients on a Web site sponsored by CLL Topics, also patient-produced and funded, reveals an interest of many cancer patients in green tea and the lengths they've gone to get educated on the topic.
While all wait for what they know will be valuable information from the ongoing Mayo trial, many have not waited and have put themselves on a protocol of EGCG capsules, which can be bought over the counter.
Members of the thread compare notes, dosages, brands and share information on medical research and studies that are ongoing.
David Bodner, of New York, is a CLL patient in remission. Bodner is a member of CLL Topics who shared his feelings with The Times.
For several months of his treatment (with his doctor's knowledge), he used EGCG capsules in parallel with traditional treatment.
"Green tea seems pretty safe, but the concentrated capsules are a little chancier and requires some reflection on things to be gained or possible problems," Bodner said in an e-mail. "But with cancer, it's probably worth a controlled try."
As a scientist, Cardelli does not promote the indiscriminate use of EGCG for cancer patients without more questions being answered.
"The problem with this approach is it is not scientifically controlled," said Cardelli, adding that the dosage of concentrated EGCG in the Feist-Weiller Cancer Center trial has been proven safe, but researchers are still looking at the effect of other dosages of the agent. "Our study brings some reason to the confusion. Perhaps if our study works, health stores will sell EGCG at a dose we have demonstrated to be useful."
The future for green tea trials
The Feist-Weiller Cancer Center researchers, including Drs. Heather Kleiner, Shile Huang, Jill Williams and John Clifford, are not stopping with prostate and breast cancer and green tea. They are seeking funding to look at the benefit of other nontraditional agents, including those found in natural products such as curry and ginger. And in a month the researchers hope to start a Phase II trial, headed by Dr. Glenn Mills, combining a traditional drug for lung cancer patients, Erlotinib, with Polyphenon E.
A future for cancer could be a more beneficial form of EGCG, says Cardelli.
"No one is envisioning you take a pill and cancer goes away," said Cardelli, who does not support an exclusively holistic approach. "But I do envision a cocktail of nontraditional and traditional but nontoxic agents that could be effective at treating cancer."
The last word
Rosso is glad researchers are looking into the benefits of green tea and other natural products, but he has always disagreed with the approach physicians take toward the treatment of illness.
"Doctors want to give you a pill or tell you to take vitamins to fix something," said Rosso, who believes one-pill answers are just masking an alarm that a lifestyle change needs to be made. "There's not just one thing you can do to make your health better. We need to change our diet, our lifestyle. That's just not emphasized enough."
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