DUARTE, Calif., April 15, 2008 — Exercise and physical activity, even in moderate amounts, can make an important difference in a woman’s risk of developing breast cancer. Researchers are looking to harness the natural affinity neural stem cells have for migrating to brain tumors to deliver targeted medicine that spares healthy neurons. Eastern and Western medicine meet in an experimental combination therapy that brings together a traditional Chinese herbal medicine with a modern chemotherapy to potentially benefit patients with liver cancer. Data from these studies by City of Hope researchers advancing the development of new targeted, personalized cancer therapies are presented at the American Association of Cancer Research (AACR) Annual Meeting in San Diego, running from April 12 through 15.
Research highlights:
“Modifiable Risk Factors for Cancer”
Educational Session (Oral Presentations)
Leslie Bernstein, Ph.D., director, Department of Etiology in the Division of Population Sciences, City of Hope, investigates the various root causes of cancer. Bernstein was one of the first researchers to examine the role of physical activity in reducing breast cancer risk. By the 1980s, cancer research had established the link between estrogen and breast cancer development and growth. Several risk factors were identified which raised a woman’s lifetime exposure to estrogen, such as early menstruation, late menopause and postponing pregnancy until later in life. Bernstein wanted to identify factors that lowered estrogen levels, and exercise was one of her targets. Findings from various studies she has conducted over the years reveal that physical activity can lower cancer risk independent of diet. Bernstein will be leading an educational session at AACR to examine and discuss how changes in lifestyle and behaviors can impact cancer risk.
“Across the world, we’ve seen consistent results showing a reduction in risk with increasing levels of activity, and we’ve seen this across all ages whether the activity was recreational or occupational,” said Bernstein. “We can’t recommend that all women become marathon runners, but even a few hours of consistent exercise each week can lower risk.”
“Neural stem cell-mediated treatment of high grade glioma: Towards clinical trials”
Abstract# 2283 (Poster Presentation)
Brain tumors have a well-deserved reputation for being a difficult cancer to treat. Not only are they located in very sensitive tissue, they can also often be located in deep regions of the brain, making them inaccessible for standard surgical removal. Karen S. Aboody, M.D., assistant professor, Neurosciences, City of Hope, investigates the potential use of neural stem cells in the treatment of brain tumors due to their ability to migrate to and congregate around tumors. She has engineered a neural stem cell line with a modified gene that can produce anticancer therapy only when it comes into contact with a prodrug, an inactive drug that only metabolizes in the presence of an activating agent. The modified neural stem cell, in conjunction with the prodrug, would potentially locally produce and concentrate the anticancer therapy to the tumor cells while sparing the healthy brain cells surrounding it. Aboody is presenting data on the development of both the novel therapy and a clinical trial program to evaluate safety.
“Our laboratory tests with the modified neural stem cell line indicate that the cells demonstrate their strong tumor tropism and ability to target therapy to tumor sites throughout the brain, and appear safe for clinical use,” said Aboody, also an assistant professor in the Division of Hematology and Hematopoietic Cell Transplantation. “This approach has the potential to limit toxicity to non-tumor tissues and improve the clinical outcome for glioma patients.”
“Phase I/II multicenter study of phy906/capeditabine in hepatocellular carcinoma”
Abstract# 4466 (Poster Presentation)
Capecitabine, marketed as Xeloda, is the first oral chemotherapy that is approved to treat breast cancer and colorectal cancer. A traditional Chinese herbal medicine that has reportedly been used for the past 1,700 years is often employed in treating diarrhea, vomiting, stomach cramps and fever. Laboratory tests have shown that PHY906, a pharmaceutical grade version of the herbal medicine, enhances the efficacy of cepacitabine against liver tumors. Yun Yen, M.D., Ph.D., director of the Department of Clinical and Molecular Pharmacology, and co-leader of the Developmental Cancer Therapeutics program at City of Hope, investigated the combination therapy of both products in early phase clinical trials for liver cancer patients.
“We found promising results with the combination therapy of PHY906 and capecitabine in patients with hepatocellular carcinoma that we believe merit additional studies in comparison to other approved liver cancer drugs” said Yen. “Of the 30 patients enrolled in the multi-center clinical trials, three patients achieved minor response and 15 achieved a stable disease state. We also found that Asians had a higher overall 12-month survival rate than non-Asians in the trial. “
According to AACR media policy, coverage of data is embargoed until the day of its presentation.