活性氧水平通过低剂量地拉罗司控制低危骨髓增生异常综合征红系祖细胞中NF-κB的激活。
Reactive oxygen species levels control NF-κB activation by low dose deferasirox in erythroid progenitors of low risk myelodysplastic syndromes.
作者信息
Meunier Mathieu, Ancelet Sarah, Lefebvre Christine, Arnaud Josiane, Garrel Catherine, Pezet Mylène, Wang Yan, Faure Patrice, Szymanski Gautier, Duployez Nicolas, Preudhomme Claude, Biard Denis, Polack Benoit, Cahn Jean-Yves, Moulis Jean Marc, Park Sophie
机构信息
CHU Grenoble Alpes, University Clinic of Hematology, Grenoble, France.
Université Grenoble Alpes, CNRS UMR 5525, Grenoble INP, CHU Grenoble Alpes, TIMC-IMAG ThEREx, Grenoble, France.
出版信息
Oncotarget. 2017 Nov 6;8(62):105510-105524. doi: 10.18632/oncotarget.22299. eCollection 2017 Dec 1.
Anemia is a frequent cytopenia in myelodysplastic syndromes (MDS) and most patients require red blood cell transfusion resulting in iron overload (IO). Deferasirox (DFX) has become the standard treatment of IO in MDS and it displays positive effects on erythropoiesis. In low risk MDS samples, mechanisms improving erythropoiesis after DFX treatment remain unclear. Herein, we addressed this question by using liquid cultures with iron overload of erythroid precursors treated with low dose of DFX (3μM), which corresponds to DFX 5 mg/kg/day, an unusual dose used for iron chelation. We highlight a decreased apoptosis rate and an increased proportion of cycling cells, both leading to higher proliferation rates. The iron chelation properties of low dose DFX failed to activate the Iron Regulatory Proteins and to support iron depletion, but low dose DFX dampers intracellular reactive oxygen species. Furthermore low concentrations of DFX activate the NF-κB pathway in erythroid precursors triggering anti-apoptotic and anti-inflammatory signals. Establishing stable gene silencing of the Thioredoxin (TRX) 1 genes, a NF-κB modulator, showed that fine-tuning of reactive oxygen species (ROS) levels regulates NF-κB. These results justify a clinical trial proposing low dose DFX in MDS patients refractory to erythropoiesis stimulating agents.
贫血是骨髓增生异常综合征(MDS)中常见的血细胞减少症,大多数患者需要输注红细胞,从而导致铁过载(IO)。地拉罗司(DFX)已成为MDS中IO的标准治疗方法,并且对红细胞生成具有积极作用。在低危MDS样本中,DFX治疗后改善红细胞生成的机制尚不清楚。在此,我们通过使用低剂量DFX(3μM)处理的红系前体细胞铁过载液体培养来解决这个问题,该剂量相当于DFX 5mg/kg/天,这是一种用于铁螯合的非常规剂量。我们发现凋亡率降低,循环细胞比例增加,两者均导致更高的增殖率。低剂量DFX的铁螯合特性未能激活铁调节蛋白,也不能支持铁耗竭,但低剂量DFX可抑制细胞内活性氧。此外,低浓度的DFX激活红系前体细胞中的NF-κB途径,触发抗凋亡和抗炎信号。对NF-κB调节剂硫氧还蛋白(TRX)1基因建立稳定的基因沉默表明,活性氧(ROS)水平的微调可调节NF-κB。这些结果为在对红细胞生成刺激剂难治的MDS患者中进行低剂量DFX的临床试验提供了依据。