Green tea extract reported to show promise against leukemia

[Guest guest]

Green tea extract reported to show 

promise against leukemia

Mayo Clinic researchers are reporting positive results in early clinical

trials using a substance in green tea.

http://www.world-science.net/othernews/090526-gallate

Scientists are reporting positive results in early leukemia clinical

trials using the chemical epigallocatechin gallate, a substance in green

tea. " The majority of individuals who entered the study with enlarged

lymph nodes saw a 50 percent or greater decline in their lymph node

size, " said Tait Shanafelt, hematologist at the Mayo Clinic in

Rochester, Minn., and lead author of the study. Moreover, " patients

tolerated the green tea extract at very high doses. " The findings

appear today online in the Journal of Clinical Oncology. The findings

tested the chemical's effect on patients with chronic lymphocytic

leukemia, the most common type of leukemia in the United States.

Currently it has no cure. The illness starts with a mutation in a single

blood cell called a lymphocyte. Over time, the altered cells multiply

and replace normal lymphocytes in the bone marrow and lymph nodes,

organs that are found all over the body and act as filters or traps for

foreign particles. The lymph nodes become enlarged as a result. About

half of patients with early stage diseases have an aggressive form of

the disease that leads to early death, researchers said. They hope the

green tea extract can stabilize early-stage patients or perhaps work in

combination with other therapies to improve their effectiveness. Green

tea is made with the leaves of Camellia sinesis, a shrub native to Asia.

In the trial, 33 patients received variations of eight different oral

doses of Polyphenon E, a proprietary compound whose primary active

ingredient is epigallocatechin gallate. Doses ranged from 400 to 2,000

milligrams twice a day. Researchers determined that they had not reached

a maximum tolerated dose, even at 2,000 mg twice per day. 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.

The studies are part of a multiyear project that began with tests of the

green tea extract on cancer cells in the laboratory of Mayo hematologist

Neil Kay, a co-author of the study. After the research showed dramatic

effectiveness in killing leukemia cells, scientists said, the findings

were applied to studies on animal tissues and then on human cells in the

lab.