LETHALITY OF NOGALAMYCIN, NOGALAMYCIN ANALOGS, AND ADRIAMYCIN TO CELLS IN DIFFERENT CELL-CYCLE PHASES

Abstract

The [antineoplastic] drugs studied included nogalamycin and its derivative 7-con-O-methylnogalarol, dis-nogamycin and its derivative 7-con-O-methylnogarol, and adriamycin. All of these drugs, especially at high doses, were lethal to [Chinese hamster ovary, CHO] cells in every phase of the cell cycle, indicating that they were not phase-specific. There were significant differences in drug sensitivity of cells in different parts of the cell cycle. Nogalamycin and adriamycin were most lethal to cells in S phase; cells in M, G1 and G2 were much less sensitive. The nogalamycin derivative 7-con-O-methylnogalarol was almost equally lethal to cells in all phases of the cell cycle. dis-Nogamycin was most lethal to cells in postmetaphase and in early S phase. Cells in mid- and late G1, late S and G2 were much less sensitive. The pattern of sensitivity to 7-Con-O-methylnogarol was different from that of dis-nogamycin. 7-con-O-Methylnogarol was most lethal to cells in early G1, S and G2. Only cells in mid- and late G1 were much less sensitive to this drug.