CHLA researchers receive TRP grant to study new way of combating relapsed ALL

Yong-Mi Kim, MD, PhD, of The Saban Research Institute of Children's Hospital Los Angeles, has been awarded a 3 year translational research program (TRP) grant from the Leukemia & Lymphoma Society to study a novel approach to eradicating minimal residual disease in patients with acute lymphoblastic leukemia (ALL).

ALL is the most common pediatric cancer. Forty years ago, only one in five children survived this disease. Today with the development of powerful chemotherapies, over 90 percent of patients can expect to be cured. Unfortunately, for those children who do not respond to therapy, the prognosis is grim. New approaches are needed for these children with relapsed ALL.

Instead of targeting only the leukemia cells, Kim plans to expand the target. "We know that leukemia cells can hide out in the bone marrow where certain other cells shield them from chemotherapy," says Kim who is also an associate professor of Pediatrics and Pathology at the Keck School of Medicine of the University of Southern California. "The focus of our research will be on those cells that harbor the leukemia cells." The surviving cancer cells have been shown to be the source of disease relapse.

Kim and her co-investigators have identified a molecule that shelters leukemia cells, an adhesion molecule called integrin alpha4. This molecule allows leukemia cells to remain in the bone marrow, sheltering them from the otherwise toxic effects of chemotherapy.

According to the researchers, there is no treatment currently available that targets this molecule for patients with leukemia. However, a novel inhibitor of integrin alpha4 is being studied for other applications.

"We will test the effects of this novel inhibitor of integrin alpha4 on residual leukemia cells, with the eventual goal of developing it for clinical use," said Kim.

Source: Children's Hospital Los Angeles