Green tea extract 'is cancer aid' | |||||||||
The tea, discovered in China nearly 5,000 years ago, has long been thought to have health benefits. But the team from the Mayo Clinic in the US found it appeared to improve the condition of four patients with chronic lymphocytic leukaemia (CLL). Experts said the Leukaemia Research journal study was interesting but more research was needed. CLL is a blood and bone marrow cancer which affects white blood cells and is the commonest type of leukaemia with over 3,000 new cases - mainly in the over 60s - diagnosed each year in the UK.
It is called chronic leukaemia because it progresses more slowly than acute leukaemia with some patients living for decades with the disease. As there is no known cure, doctors have traditionally not intervened in the early stages of the disease to see how it develops, before moving on to traditional forms of cancer treatment such as chemotherapy. But the Mayo researchers decided to try green tea after a test tube study in 2004 showed it killed leukaemia cells. Four CLL patients being treated at the clinic took green tea extract tablets containing epigallocatechin gallate, an antioxidant thought to fight cancer cells. Doctors Within a few months, doctors realised that three out of four patients were showing signs of the cancer regressing. The fourth patient also showed a slight improvement, but it was not judged to be clinically relevant. Report author Tait Shanafelt said: "Green tea has long been thought to have cancer-prevention capabilities. It is exciting that research is now demonstrating this agent may provide new hope for CLL patients. "The experience of these individuals provides some suggestion that our previously published laboratory findings may actually translate into clinical effects for patients with this disease." But he warned more research was needed to prove the findings on a larger scaled and whether there were any side effects. Ken Campbell, clinical information officer at the Leukaemia Research Fund, said: "The findings are interesting, but we cannot say yet this is a new treatment for cancer. "We need to carry out a large scale, controlled trial to see if the findings hold true." | |||||||||
It's likely that the compounds in green tea act through many different pathways 
Green tea has long been thought to have cancer-prevention capabilities. It is exciting that research is now demonstrating this agent may provide new hope for CLL patients 
| Cancer hope for green tea extract | ||||
Tests by UK and Spanish researchers showed polyphenol EGCG taken from green tea leaves inhibits cancer cell growth. The effect was seen even at low concentrations, equivalent to drinking two or three cups of green tea a day. However, the study, published in Cancer Research, also found high concentrations of the chemical may increase the risk of birth defects.
Previous research has suggested that drinking green tea helps to cut the risk of certain forms of cancer. The latest study found that EGCG binds to a key enzyme - dihydrofolate reductase (DHFR) - that is targeted by established anti-cancer drugs. This stops the enzyme from triggering the manufacture of new DNA in tumour cells. It appears to work in the same way as the cancer drug methotrexate - but in practice would probably have fewer side effects. Drug development Professor Roger Thorneley, from the John Innes Centre in Norwich, conducted the research with team from the University of Murcia in Spain. He said: "This is a very exciting discovery. For the first time we have a clear scientific explanation of why EGCG inhibits the growth of cancer cells at concentrations which are found in the blood of people who drink two or three cups of green tea a day. "We have identified the enzyme in tumour cells that EGCG targets and understand how it stops this enzyme from making DNA. "This means we may be able to develop new anti-cancer drugs based on the structure of the EGCG molecule." Fellow researcher Dr Jose Neptuno Rodriguez-Lopez said: "We decided to look at EGCG because we recognised that its structure is very similar to that of the successful anti-cancer drug methotrexate. "We discovered that EGCG can kill cancer cells in the same way as methotrexate. "However, because EGCG binds to the target enzyme less tightly than methotrexate, it should have decreased side effects on healthy cells." Fewer side effects Dr Rodriguez-Lopez said the researchers were now using EGCG as the starting point to design and develop effective new anti-cancer drugs that kill tumour cells but inflict less damage on healthy cells. Previous studies have also linked high levels of green tea consumption around the time of conception and during pregnancy with an increased incidence of neural tube defects such as spina bifida. These defects are associated with a lack of the key nutrient folic acid. The scientists said EGCG in green tea would be expected to cause a significant drop in folic acid levels. http://news.bbc.co.uk/2/hi/health/4348059.stm
Green tea could cut arthritis risk  Green tea is thought to have many health benefits Drinking green tea could help keep arthritis at bay, say scientists. The tea, first discovered in China nearly 5,000 years ago, has long been thought to be beneficial to health. It has been linked to preventing coronary heart disease, stroke and certain types of cancer. But now researchers in Sheffield have found that two compounds found in green tea, EGCG (epigallocatchin gallate) and ECG (epicatechin gallate) can help prevent osteoarthritis by blocking the enzyme that destroys cartilage. Benefits Dr David Buttle, of the University of Sheffield, said laboratory tests showed the benefits of regular green tea consumption. "Green tea should be drunk as a prophylactic to prevent disease. "If you have fairly severe joint damage it may be too late to do anything about it, but if you spend decades of your life drinking green tea in the end it may be beneficial."
He said that one of the compounds EGCG had been shown specifically to protect the cartilage. "We have shown that EGCG protects cartilage destruction in test-tube models of cartilage loss that mimic what happens in the arthritic joint, and work by others suggests that EGCG reduces joint swelling and pain. "We now need to do more tests. and then further work on human volunteers." Research Sheffield University, where Dr Buttle works, has now taken out a patent for the use of EGCG in treating osteoarthritis. The Arthritis Research Campaign, which partly funded the research, said the initial results were promising. A spokeswoman said: "Dr Buttle's findings are of great interest, and although further research needs to be done, in the mean time people should drink green tea as it's not going to do them any harm - and may in fact do them a lot of good." | ||||
Green tea should be drunk as a prophylactic to prevent disease
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