French researchers are working on a potential new treatment for acute myeloid leukemia, a cancer of the white blood cells that commonly strikes people who were previously treated for cancer.

Normally, bone marrow makes cells called blasts that mature into several different types of blood cells that have specific functions. In acute myeloid leukemia (AML), however, the blasts do not mature and become too numerous.

These immature blast cells are found in the blood, bone marrow, liver, spleen and lymph nodes. People with AML tend to have severe anemia (iron-poor blood) and are prone to infection, inflammation, and blood clotting disorders.

Reporting in the June issue of Nature Medicine, Dr. Florence Smadja-Joffe and colleagues at the Hopital Paul-Brousse in France targeted a protein called CD44 located on the cell surface and hyaluronan, which is a molecule that binds to CD44. Both are involved in cell maturation (differentiation).

By using three specific antibodies against CD44 and hyaluronan on blast cells from blood or bone marrow of AML patients, they found that the antibodies were able to bind to CD44 and relieve the block this protein puts on cell differentiation.

“Although many questions remain to be answered, these provocative findings may stimulate investigation into the clinical potential for CD44-targeted differentiation therapy,” wrote Dr. Paul W. Kincade, of the Oklahoma Medical Research Foundation, Oklahoma City, in an editorial accompanying the new study.

“This intriguing new paper should create fresh interest in the role of CD44,” he added.