Green tea extract shows promise in leukemia trials

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 lymph nodes 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 green tea extract on cancer cells in the laboratory of Mayo hematologist Neil Kay, M.D., a co-author on this article. After laboratory research showed dramatic effectiveness in killing leukemia 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 patients 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.

VIDEO ALERT: Additional audio and video resources, including comments by Dr. Shanafelt describing the research, are available on the Mayo Clinic News Blog. These materials are also subject to embargo but may be accessed in advance by journalists for incorporation into stories. The password for this post is gteacll.

The study was sponsored by Mayo Clinic, the CLL Global Research Foundation, CLL Topics (including contributions by individual CLL patients) and the Commonwealth Foundation for Cancer Research. Medication for the study was provided by Polyphenon E International. Others on the research team were Timothy Call, M.D.; Clive Zent, M.D.; Betsy LaPlant; Deborah Bowen; Michelle Roos; Charla Secreto; Asish Ghosh, Ph.D.; Brian Kabat; Diane Jelinek, Ph.D.; and Charles Erlichman, M.D., all of Mayo Clinic; and Mao-Jung Lee, Ph.D., and Chung Yang, Ph.D., both of Rutgers University.

About Mayo Clinic

Mayo Clinic is the first and largest integrated, not-for-profit group practice in the world. Doctors from every medical specialty work together to care for patients, joined by common systems and a philosophy of “the needs of the patient come first.” More than 3,300 physicians, scientists and researchers and 46,000 allied health staff work at Mayo Clinic, which has sites in Rochester, Minn., Jacksonville, Fla., and Scottsdale/Phoenix, Ariz. Collectively, the three locations treat more than half a million people each year. To obtain the latest news releases from Mayo Clinic, go to www.mayoclinic.org/news. MayoClinic.com (www.mayoclinic.com) is available as a resource for your health stories.

Media Contact

Robert Nellis EurekAlert!

More Information:

http://www.mayo.edu

All latest news from the category: Health and Medicine

This subject area encompasses research and studies in the field of human medicine.

Among the wide-ranging list of topics covered here are anesthesiology, anatomy, surgery, human genetics, hygiene and environmental medicine, internal medicine, neurology, pharmacology, physiology, urology and dental medicine.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors