Molecular biology of leukemia for the clinician

Although significant progress has been made in the treatment of the acute leukemias, therapies are generally non-specific and not targeted at the biologic defects underlying these diseases. Consequently, treatment results are suboptimal. The development of leukemic cell phenotype-specific therapies is hampered by our limited knowledge of the biology of acute leukemias. That characterizing the genetic defect may revolutionize treatment approach and disease outcome has recently been proven in acute promyelocytic leukemia. Once identified, genes involved in the pathogenesis of leukemic subtypes not only allow for improved diagnosis and monitoring of minimal residual leukemic cells but may ultimately lead to the development of innovative drug strategies that aim at the inhibition of disease-related genes or their encoded proteins. The focus of this review is to familiarize the practicing physician with some principles of molecular biology and with its current and future goals with respect to leukemia.