Inhibition　of　haringtonine-induced　apoptosis　by　tetradecanoylphorbol　acetate　in　human　leukemia　HL-60　

Inhibition of harringtonine induced apoptosis by tetradecanoylphorbol acetate in human leukemia HL 60 cells

目的：研究十四酰佛波乙酸酯（ＴＡ）预处理后，三尖杉酯碱（Ｈａｒ）和喜树碱（Ｃａｍ）诱导人白血病ＨＬ６０细胞凋亡的变化．方法：染色质凝集观察，流式细胞术，ＤＮＡ琼脂糖凝胶电泳和点杂交．结果：ＴＡ２００ｎｍｏｌ·Ｌ－１预处理ＨＬ６０细胞６ｈ，明显抑制Ｈａｒ０１ｍｇ·Ｌ－１作用３ｈ诱导的细胞凋亡，但只部分抑制Ｃａｍ０２ｍｇ·Ｌ－１作用３ｈ诱导的细胞凋亡．ＴＡ预处理ＨＬ６０细胞明显降低ｃｍｙｃ基因的表达．结论：ＴＡ明显抑制由Ｈａｒ和部分抑制由Ｃａｍ诱导的ＨＬ６０细胞凋亡，而且ＴＡ预处理的细胞中ｃｍｙｃ基因表达明显下降，这可能导致了对诱导细胞凋亡的抑制．

AIM: To study the changes of the apoptosis induced by camptothecin (Cam) or harringtonine (Har) in human leukemia HL 60 cells after the cells were preincubated with tetradecanoylphorbol acetate (TA). METHODS: Chromatin condensation observation, flow cytometry, DNA agarose gel electrophoresis, and Dot blot hybridization. RESULTS: [CX1〗After the HL 60 cells were preincubated with TA 200 nmol·L -1 for 6 h, the apoptosis induced by Har 0 1 mg·L -1 for 3 h was drastically inhibited, and the apoptosis by Cam 0 2 mg·L -1 for 3 h was partly inhibited. On the other hand, the expression level of c myc gene in HL 60 cells decreased apparently after the preincubation of TA. CONCLUSION: TA preincubation inhibited the apoptosis induced by Har obviously or by Cam partly in human leukemia HL 60 cells, and the expression of c myc gene decreased drastically in the preincubated cells, which might result in the inhibition of apoptosis.