apoptosis inducing effect of spiroaminopyrimidine analogue in nb4 leukemia cells via down-regulation of birc5 expression

Background and aim: it has been reported that spiroaminopyrimidine derivatives inhibited the growth and proliferation of various cancer cell lines. in the present study, we evaluated cytotoxic and apoptosis-inducing effects of 2,4-diamino-1,3-diazaspiro[5.5]-9-tert-butyl-2, 4-diene-5-carbonitril (9-tbap) on nb4 acute promyelocytic leukemia (apl) cells.methods: the cells were treated with 10–100 µm of 9-tbap. cytotoxic activity of the compound was measured using the mtt assay. apoptosis was investigated by hoechst 33258 staining as well as by annexin v/pi double staining.results: the compound under study was found to be highly active cell growth inhibitor with ic50 of 30.0 ± 3.5 µm inducing apoptosis in nb4 cells. cell cycle analysis by flow cytometry showed a time-dependent increase in sub-g1 cell population. real-time polymerase chain reaction analysis revealed that the treatment with the compound down-regulated the birc5 expression in a time-dependent manner.conclusion: 9-tbap displayed potent anti- leukemic activity in vitro thus warranting further investigation.