Objective: To explore the effects of dexamethasone (DXM) and vincristine (VCR) on cytosine arabinoside (Ara-C) induced apoptosis and activation of nuclear factor-k-gene binding (NF-kB) in leukemic cell line HL60-n. M...Objective: To explore the effects of dexamethasone (DXM) and vincristine (VCR) on cytosine arabinoside (Ara-C) induced apoptosis and activation of nuclear factor-k-gene binding (NF-kB) in leukemic cell line HL60-n. Methods: Apoptosis of HL60-n cells was analysed by TdT-mediated X-dUTP nick and end labeling (TUNEL) and DNA electrophoresis. NF-kB activity of HL60-n cells was detected by electrophoretic mobility shift assay (EMSA). Results: There was slight activation of NF-kB in HL60-n cells without drug induction. Ara-C at 1 mmol/L significantly enhanced the activation of NF-kB in HL60-n cells. The level of NF-kB activation induced by DXM at 1 mmol/L or VCR at 0.1 mmol/L had no significant difference compared with that of the control group. However, in HL60-n cells pre-treated with 1 mmol/L of DXM or 0.1 mmol/L of VCR, the activation of NF-kB induced by 1 mmol/L of Ara-C was significantly suppressed with inhibition rates of 31.0% and 47.0%, respectively. The apoptosis rates of HL60-n cells induced by 1.0 mmol/L, 10 mmol/L and 100 mmot/L Ara-C were 45.003.16%, 61.883.40% and 77.624.75%, respectively. The apoptotic rates of HL60-n cells induced by DXM at 1 mmol/L or VCR at 0.1 mmol/L were similar to that of the control group. However, either DXM at 1 mmol/L or VCR at 0.l mmol/L could enhance the apoptosis of HL60-n cells induced by Ara-C at 1 mmol/L with rates of 39.1% and 59.2%, respectively. Conclusion: Ara-C can induce apoptosis and activation of NF-kB in HL60-n cells. The mechanism of increased apoptosis of HL60-n cells by DXM or VCR may be related to suppression of NF-kB activation.展开更多
基金This work was supported by the National Natural Science Foundation of China (No. 39770330).
文摘Objective: To explore the effects of dexamethasone (DXM) and vincristine (VCR) on cytosine arabinoside (Ara-C) induced apoptosis and activation of nuclear factor-k-gene binding (NF-kB) in leukemic cell line HL60-n. Methods: Apoptosis of HL60-n cells was analysed by TdT-mediated X-dUTP nick and end labeling (TUNEL) and DNA electrophoresis. NF-kB activity of HL60-n cells was detected by electrophoretic mobility shift assay (EMSA). Results: There was slight activation of NF-kB in HL60-n cells without drug induction. Ara-C at 1 mmol/L significantly enhanced the activation of NF-kB in HL60-n cells. The level of NF-kB activation induced by DXM at 1 mmol/L or VCR at 0.1 mmol/L had no significant difference compared with that of the control group. However, in HL60-n cells pre-treated with 1 mmol/L of DXM or 0.1 mmol/L of VCR, the activation of NF-kB induced by 1 mmol/L of Ara-C was significantly suppressed with inhibition rates of 31.0% and 47.0%, respectively. The apoptosis rates of HL60-n cells induced by 1.0 mmol/L, 10 mmol/L and 100 mmot/L Ara-C were 45.003.16%, 61.883.40% and 77.624.75%, respectively. The apoptotic rates of HL60-n cells induced by DXM at 1 mmol/L or VCR at 0.1 mmol/L were similar to that of the control group. However, either DXM at 1 mmol/L or VCR at 0.l mmol/L could enhance the apoptosis of HL60-n cells induced by Ara-C at 1 mmol/L with rates of 39.1% and 59.2%, respectively. Conclusion: Ara-C can induce apoptosis and activation of NF-kB in HL60-n cells. The mechanism of increased apoptosis of HL60-n cells by DXM or VCR may be related to suppression of NF-kB activation.
文摘本研究通过观察抗CXCR4单克隆抗体12G5对Ara C杀伤HL-60细胞效应的影响,评价其在白血病骨髓 残留病变中的治疗价值。培养并共培养HL-60细胞,在共培养体系中采用12G5(10μg／ml)阻抑基质细胞SDF-1的 生物作用后,通过MTT法及细胞形态学观察检测不同浓度Ara c对HL-60细胞杀伤作用的变化。药物杀伤效应曲 线显示,在20μg／ml Ara C组,对照组中前2天A540值明显下降,但从3-4天开始出现上升,而加12G5实验组中 A540值虽然下降平缓,但持续下降,并于观察第5天后低于对照组,整个观察期中未出现反弹。在40μg／ml Ara C 组,对照组A540在0-3天明显下降,从第4天开始回升,于第5-6天与实验组曲线交叉,从7-12天时照组A540值 总体呈上升趋势,并明显高于实验组,而加12G5实验组曲线在整个观察期间虽然在7-9天有小幅度攀升,但总的 趋势是下降。细胞形态学观察显示,在两个浓度组,对照组HL-60细胞数量最初明显减少,随着培养时间延长,细 胞数量逐渐增多,实验组结果正相反。结论:12G5减弱Ara C对HL-60细胞的早期杀伤作用,但12G5增强Ara C 总体杀伤作用,同时,延缓HL-60细胞对Ara c的耐药性,因此12G5有助于白血病骨髓残留病变的治疗。
