Drug takes a shot at leukemia cells.

A drug that targets solid tumors such as those of lung cancer might also fight blood cancers, a lab study shows.

Erlotinib (Tarceva) attacks cells by blocking a receptor protein that's abundant on the surface of some cancer cells (SN: 8/27/05, p. 139). Bone marrow cells--the blood-forming cells that go awry in patients with leukemia and other blood cancers--typically don't display this receptor.

Nevertheless, physician Simone Boehrer of the Gustave-Roussy Institute in Villejuif, France, and her colleagues tested erlotinib in a lab dish on bone marrow cells taken from 10 patients with either acute myeloid leukemia or a precancerous blood disorder called myelodysplastic syndrome.

While cells from some patients were resistant to erlotinib, the drug killed up to 60 percent of cancerous cells extracted from other patients with either disease.

The resistant cancer cells were high in a protein called nucleophosmin. Measuring nucleophosmin concentrations in cancer cells might pinpoint leukemia patients who could benefit from erlotinib, Boehrer says. In lab tests, shutting down nucleophosmin production boosted erlotinib's killing power, the researchers found.