Green tea in smoking-related bladder cancer trials

Green tea extract is being tested by UCLA cancer researchers to see if combined with a molecularly targeted therapy, it will prevent the recurrence of bladder cancer in former smokers.

The Jonsson Comprehensive Cancer Center at the School of Public Health at UCLA, along with the departments of Urology, Medicine, Pathology, are seeking hundreds of former smokers who have had bladder cancer to try and determine whether these agents will prevent the disease recurring.

The clinical trial will test the experimental drugs Polyphenon E, a green tea extract, and the drug Tarceva, which has been shown to reduce the growth of advanced cancers in patients with lung and other epithelial cell tumors.

One group of patients will receive the green tea extract, which has been shown in UCLA and other laboratories to reduce the growth of bladder cancer tumors both in animals and in humans. The second group will receive Tarceva, while the third group will receive a placebo.

"We'll study how to prevent cancer recurrence and progression in former smokers who have already had bladder cancer, but our goal is to develop effective prevention strategies for people who may be at risk but who do not yet have bladder cancer," said Dr Arie Belldegrun, head of urologic oncology, who is leading the project with Dr Robert Figlin, a professor of hematology/oncology and urology, and Dr Allan Pantuck, an assistant professor of urology.

In additional to the clinical trial, researchers also will develop biomarker tests to help predict who will get bladder cancer, discover the molecular profile of the disease to identify those most at risk, and create a tumor bank to help with scientific research.

Bladder cancer is the fifth most common cancer in the US, with more than 56,000 new cases diagnosed each year. As many as half of all bladder cancers are believed to be related to cigarette smoking. Without a reliable, non-invasive way to diagnose the disease, bladder cancer can be difficult to detect in the early, most treatable stages. When not found early, these tumors are generally very aggressive, with more than half of advanced bladder cancer patients experiencing recurrences.

Risk factors besides tobacco smoking include age, being a man - men are two to three times more likely to get bladder cancer than women - family history and race - Caucasians are two to three times more likely to get bladder cancer than African Americans, Latinos or Asians. Smoking-related bladder cancer has a 20-year latency period, UCLA researchers said, meaning that it takes about 20 years for the cancer to develop in smokers and former smokers. Howevever, not all smokers and former smokers develop bladder cancer and UCLA researchers want to find out why.

"We're looking for specific biologic signals that tell us why some people get this disease and others don't," Figlin said. "We want to decrease bladder cancer occurrence and develop molecular profiles that tell us who is most at risk."

The research will be funded by a $7 million grant from the National Cancer Institute (NCI) with supplemental funds from the NCI Office of Complementary and Alternative Medicine.