The basis for treatment of myelodysplastic syndrome and acute nonlymphoblastic leukemia with biologic agents

A number of cloned biologic factors are currently available that are candidates for therapy of myelodysplastic syndromes and, by extension, acute nonlymphoblastic leukemia. gamma-Interferon and, to a greater extent, tumor necrosis factor exhibit leukemic differentiative effects without the potential for stimulation of leukemic clones. These effects may be enhanced by combinations of these with one another or with chemical inducers of differentiation such as retinoic acid or vitamin D derivatives. The colony-stimulating factors clearly have potent in vivo effects upon hematopoiesis. The lineage specific factors (G- or M-CSF) may have greater differentiation induction potential and less risk of accelerating emergence of leukemic clones than the earlier acting factors (GM- or multi-CSF). Thus, several potentially fruitful avenues for clinical research are currently available.