Responses of human bone marrow progenitor cells to fluoro-ara-AMP, homoharringtonine, and elliptinium.

The cytotoxicity of the investigational anticancer drugs fluoro-ara-AMP, homoharringtonine, and elliptinium on normal human granulocyte-macrophage colony-forming units in culture (GM-CFU) was investigated using a bilayer soft agar system. For each drug, the dose-dependent survival curve on a semilogarithmic plot formed a straight line. The D0 were: 0.51 microgram/ml (fluoro-ara-AMP), 0.004 microgram/ml (homoharringtonine) and 0.026 microgram/ml (elliptinium). The in vitro toxicity of drugs on bone marrow progenitor cells did not correlate with the relative myelosuppressive potency observed in vivo.