"This study will test the hypothesis that Ontak improves tumor immunity by killing regulatory T cells (Tregs) in patients with advanced-stage ovarian cancer," says principal investigator Tyler Curiel, professor of medicine and chief of hematology and medical oncology at Tulane. "When a patient has cancer, some of the immune cells in the body begin to kill the body's tumor-killing immune cells instead of killing the tumor. So it's like friendly fire -- soldiers, instead of going out and shooting the enemy, shoot their own soldiers instead."
In the journal Nature Medicine, Tulane scientists reported how Tregs impede the body's ability to fight ovarian cancer. The Tulane research team showed that human tumor Treg cells suppress tumor immunity and contribute to growth of tumors. Thus, killing Treg cells may help treat cancer, Curiel says.
The National Cancer Institute awarded a four-year grant of more than $1.2 million for the Tulane team to continue studying how ovarian tumors undermine immunity and continue to grow. The Tulane team hopes this novel treatment approach, using Ontak to deplete Tregs, will prove beneficial not only for ovarian cancer, but also for other cancers in future studies, including breast and lung cancer, Curiel says.
Ontak has been approved by the U.S. Food and Drug Administration for the treatment of patients with cutaneous T-cell leukemia/lymphoma.