New Retinoid SX-116 Induces Apoptosis of Acute Promyelocytic Leukemia Cell Line NB4 / 中国实验血液学杂志

ABSTRACT

In this research, the effect of novel retinoid SX-116 on acute promyelocytic leukemia cell line NB4 was studied in vitro. Cell proliferation, cell morphological characters, flow cytometry, DNA electrophoresis and RT-PCR were observational parameters. The results showed that treated with SX-116 at 10(-6) mol/L, the growth and survival of NB4 cells were markedly inhibited, morphological changes of apoptosis, including membrane blebbing, chromosome condensation and fragmentation of nuclei were observed in NB4 cells after 24 hours exposure of SX-116. Further studies showed "DNA ladder" in genomic DNA electrophoresis, as well as a typical apoptotic peak below G(1) phase presented in flow cytometry. The expression of apoptosis - related gene bcl-2 and p53 were examined. The level of bcl-2 mRNA was downregulated by 6-hour treatment of SX-116, while the gene restored to the normal level by following 12-, 24- and 48-hour exposure. However, p53 mRNA was unchanged during the treatment. The results demonstrated that SX-116 could induce apoptosis of NB4 cells while the mechanism remains to be studied.