Arachidonate 5-lipoxygenase inhibitors show potent antiproliferative effects on human leukemia cell lines.

Cirsiliol and AA861, specific arachidonate 5-lipoxygenase inhibitors, showed potent antiproliferative effects on human leukemic cell lines K562, Molt4B and HL60. On the other hand, HeLa cells were not affected by these drugs. In the inhibitor treated and growth retarded leukemia cells, the rates of synthesis of DNA, RNA and protein were markedly decreased. These results suggested that arachidonate 5-lipoxygenase or leukotrienes would play essential roles in cellular functions of leukemic cells.