Status of colony-stimulating factors in cancer and AIDS

The major hematopoietic growth factors have been produced through recombinant DNA technology and have entered initial clinical trials; results of these trials will be reviewed here. Granulocyte colony-stimulating factor (G-CSF) has been tested in patients with bladder cancer and small-cell carcinoma of the lung. In these studies, G-CSF ameliorated the leukopenia associated with combination chemotherapy, reduced the incidence of mucositis in the bladder cancer patients, and nearly eliminated the occurrence of serious infections in the lung cancer patients. Trials involving another factor, granulocyte macrophage colony-stimulating factor (GM-CSF), have resulted in a marked increase in white blood cell (WBC) counts in patients with myelodysplastic syndromes, and has accelerated the appearance of leukocytes and platelets after autologous bone marrow transplants. GM-CSF can also increase the WBC counts in acquired immunodeficiency syndrome patients treated with zidovudine. Both G-CSF and GM-CSF may produce multilineage effects in certain clinical settings and dose ranges. Finally, interleukin-1 (IL-1) and IL-3, which commit very early stem cells to a myeloid pathway, may be used in combination with G-CSF or GM-CSF to produce a synergistic response to various clinical situations.