Eight Newly Identified Genes Help Predict A Melanoma Patient's Response To Treatment

"Approximately 70,000 people will be diagnosed with metastatic melanoma this year," said principal investigator Hussein Tawbi, M.D., M.Sc., assistant professor of medicine, University of Pittsburgh School of Medicine, and with UPCI's Melanoma Program. "This form of cancer is aggressive and often resistant to chemotherapy. In fact, only 7 to 10 percent of patients are likely to respond to the current standard of care. We wanted to see if there was a way to predict which patients would respond to treatment and which ones would not."

Dr. Tawbi and his colleagues examined the tumor tissues of 21 patients with metastatic melanoma, some of whom responded to chemotherapy and some who did not. Once the cases were divided, the researchers used a mathematical tool called Neural Network Analysis to survey over 25,000 genes and the regulators that turn the genes on and off to see if they could identify ones that could distinguish responders from nonresponders.

"Cancer cells contain massive amounts of information that, if analyzed appropriately, may inform us how to kill them," said Dr. Tawbi. "They contain thousands of genes, and every gene has a switch that turns it on or off. Neural Network Analysis, which utilizes pattern recognition algorithms, helped us identify a signature of eight genes and their switches that predict a patient's likelihood of responding to treatment for metastatic melanoma."

The results of this study are being validated in a larger sample of 80 patients. Genetic testing could someday allow doctors to identify which patients will respond to standard chemotherapy and which patients won't, leading to improved treatments for both groups.

"The genes that we isolated in this study could be potential targets for new therapies down the road," explained Dr. Tawbi. "We need to find options for the large number of patients with metastatic disease who won't respond to existing treatments. This work takes us one step closer to doing so."

The new findings are being presented at the 45th annual meeting of the American Society of Clinical Oncology (ASCO), May 29 to June 2, in Orlando, Fla.

The study was funded by the Eastern Cooperative Oncology Group and the University of Pittsburgh Cancer Institute.