Researchers at City of Hope may have found a way to make certain lung tumors more vulnerable to a cancer-fighting drug, potentially battling tumors’ stiff resistance to the chemotherapy.
|Karen Reckamp (Photo by Walter Urie)|
One of today’s standard treatments for non-small cell lung cancer targets the epidermal growth factor receptor (EGFR) in tumor cells, which spurs tumors’ growth and development, explained Karen Reckamp, M.D., M.S., assistant professor in the Department of Medical Oncology & Therapeutics Research. Unfortunately, only about 10 percent of lung cancer patients respond to this treatment. Most tumors either immediately overcome the drug, known as an EGFR inhibitor, or they become resistant over time.
But results from early clinical trials of a new strategy are promising. The strategy combines an EGFR inhibitor with another drug called a COX-2 inhibitor, which may make the therapy more effective. Reckamp presented data from a phase I clinical trial of the EGFR inhibitor erlotinib and a COX-2 inhibitor called apricoxib at the recent annual meeting of the American Association for Cancer Research in Denver.
According to Reckamp, patients on the trial whose advanced lung cancer had resisted EGFR inhibitors earlier actually saw their cancers stabilize, which means the cancers slowed or stopped growing and did not spread.
The COX-2 enzyme is highly active in lung tumors, and studies have linked high levels of the enzyme to tumor development and survival. Suppressing COX-2 might directly influence tumor development; it may also make EGFR-inhibiting drugs more effective, researchers believe.
“Apricoxib is a novel COX-2 inhibitor that was developed specifically for use in cancer,” she said.
The randomized study enrolled 20 patients with advanced non-small cell lung cancer. They received erlotinib with varying doses of apricoxib, depending on their study group. Results encouraged the researchers to take the strategy further.
“We are now conducting a phase II trial with an existing COX-2 inhibitor celecoxib, originally approved to treat arthritis pain, which we can potentially repurpose to make cancer therapies more effective,” said Reckamp.