For Immediate Release
April 21, 2009

BUFFALO, NY – Scientists at Roswell Park Cancer Institute have created a pharmacodynamic model to understand how arsenic trioxide (ATO), combined with specific heat shock protein (HSP) 90 inhibitors, may enhance cancer cell death in acute myeloid leukemia (AML), a cancer with poor outcomes. The analysis, led by Meir Wetzler, MD, Department of Medicine, Roswell Park Cancer Institute (RPCI), will be presented at the American Association for Cancer Research (AACR) 100th Annual Meeting 2009, April 18 -22 in Denver, CO.

Arsenic and its derivatives have been used for more than 2000 years, both as poisons and as therapeutic agents. Scientists are now characterizing the underlying mechanisms of arsenic trioxide and its interactions with different proteins to enhance its potential as a treatment for patients diagnosed with AML. Using a pharmacodynamic drug-drug model, Dr. Wetzler and colleagues from the University at Buffalo Department of Pharmacology analyzed arsenic trioxide’s effect on transcription 3 (STAT3) and heat shock proteins 70 and 90.

In a previous study, they found that patients whose AML cells have activated STAT3 have a worse outcome. Arsenic trioxide appears to downregulate STAT3 activity. To augment arsenic trioxide’s effectiveness, Dr. Wetzler targeted heat shock protein 90, which protects from arsenic trioxide degradation. HSP 90 inhibitor augmented ATO’s effect. However both upregulated heat shock protein 70, which prevents cancer cell death.

“We believe that pharmacodynamic modeling offers a method to better understand the interactions among cancer cell proteins and drugs. This understanding will help us to develop more effective clinical trials and lead to the development of new therapeutic options for patients diagnosed with AML,” said Dr. Wetzler.

More than 13,290 new AML cases are diagnosed each year in the United States. AML is the most common type of acute leukemia, and more than 8,820 die from the disease. AML is a fast-growing cancer in which the bone marrow makes abnormal myeloblasts. Normally, myeloblasts develop into white blood cells that fight infection.

Roswell Park Cancer Institute, founded in 1898, is the nation’s first cancer research, treatment and education center and is the only National Cancer Institute-designated comprehensive cancer center in Upstate New York. RPCI is a member of the prestigious National Comprehensive Cancer Network, an alliance of the nation’s leading cancer centers. Roswell Park has affiliate sites and collaborative programs in New York, Pennsylvania, and in China. For more information, visit RPCI’s website at www.roswellpark.org, call 1-877-ASK-RPCI (1-877-275-7724) or e-mail askrpci@roswellpark.org.

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