Green tea extract shows promise in leukemia trials

May 26, 2009

Mayo Clinic researchers are reporting positive results in early leukemia clinical trials using the chemical epigallocatechin gallate (EGCG), an active ingredient in green tea. The trial determined that patients with chronic lymphocytic leukemia (CLL) can tolerate the chemical fairly well when high doses are administered in capsule form and that lymphocyte count was reduced in one-third of participants. The findings appear today online in the Journal of Clinical Oncology.

"We found not only that patients tolerated the green tea extract at very high doses, but that many of them saw regression to some degree of their chronic lymphocytic leukemia," says Tait Shanafelt, M.D., Mayo Clinic hematologist and lead author of the study. "The majority of individuals who entered the study with enlarged saw a 50 percent or greater decline in their lymph node size."

CLL is the most common subtype of leukemia in the United States. Currently it has no cure. Blood tests have enabled early diagnosis in many instances; however, treatment consists of watchful waiting until the disease progresses. Statistics show that about half of patients with early stage diseases have an aggressive form of CLL that leads to early death. Researchers hope that EGCG can stabilize CLL for early stage patients or perhaps improve the effectiveness of treatment when combined with other therapies.

The research has moved to the second phase of clinical testing in a follow-up trial -- already fully enrolled -- involving roughly the same number of patients. All will receive the highest dose administered from the previous trial.

These clinical studies are the latest steps in a multiyear bench-to-bedside project that began with tests of the extract on in the laboratory of Mayo hematologist Neil Kay, M.D., a co-author on this article. After laboratory research showed dramatic effectiveness in killing cells, the findings were applied to studies on animal tissues and then on human cells in the lab. (See "Green Tea and Leukemia" in Discovery's Edge magazine.)

In the first clinical trial, 33 received variations of eight different oral doses of Polyphenon E, a proprietary compound whose primary active ingredient is EGCG. Doses ranged from 400 milligrams (mg) to 2,000 mg administered twice a day. Researchers determined that they had not reached a maximum tolerated dose, even at 2,000 mg twice per day.

More information: jco.ascopubs.org/

Source: Mayo Clinic (news : web)

Explore further: AstraZeneca cancer drug, companion test approved

add to favorites email to friend print save as pdf

Related Stories

Multiple myeloma clinical trial closes early

Apr 05, 2007

Mayo Clinic Cancer Center announced today that a multiple myeloma clinical trial has shown a significant improvement in survival with lenalidomide plus low-dose dexamethasone therapy compared to lenalidomide plus high-dose ...

Recommended for you

Putting the brakes on cancer

Dec 19, 2014

A study led by the University of Dundee, in collaboration with researchers at our University, has uncovered an important role played by a tumour suppressor gene, helping scientists to better understand how ...

Peanut component linked to cancer spread

Dec 19, 2014

Scientists at the University of Liverpool have found that a component of peanuts could encourage the spread and survival of cancer cells in the body.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.