In vitro studies on cellular and molecular mechanisms of arsenic trioxide (As2O3) in the treatment of acute promyelocytic leukemia: As2O3 induces NB4 cell apoptosis with downregulation of Bcl-2 expression and modulation of PML-RAR alpha/PML proteins.
In vitro studies on cellular and molecular mechanisms of arsenic trioxide (As2O3) in the treatment of acute promyelocytic leukemia: As2O3 induces NB4 cell apoptosis with downregulation of Bcl-2 expression and modulation of PML-RAR alpha/PML proteins.
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DOI：
10.1182/blood.v88.3.1052.bloodjournal8831052
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发表时间：
1996
期刊：
影响因子：
20.3
通讯作者：
G. Q. Chen;J. Zhu;X. Shi;J. Ni;H. Zhong;G. Y. Si;X. L. Jin;W. Tang;X. Li;S. Xong;Z. X. Shen;G. Sun;J. Ma;P. Zhang;T. D. Zhang;C. Gazin;T. Naoe;S. J. Chen;Z. Y. Wang;Z. Chen
中科院分区：
文献类型：
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作者：
G. Q. Chen;J. Zhu;X. Shi;J. Ni;H. Zhong;G. Y. Si;X. L. Jin;W. Tang;X. Li;S. Xong;Z. X. Shen;G. Sun;J. Ma;P. Zhang;T. D. Zhang;C. Gazin;T. Naoe;S. J. Chen;Z. Y. Wang;Z. Chen
最近，中国的研究表明，三氧化二砷是治疗急性早幼粒细胞白血病的一种非常有效的方法。对全反式维甲酸(ATRA)和常规化疗耐药的APL患者仍然可以对As203有反应。在这项研究中，我们以NB4细胞为模型，探讨了这种治疗的可能的细胞和分子机制。结果表明：(1)在微摩尔浓度范围内，As_2O_3可诱导NB4细胞发生相对特异的细胞凋亡，细胞形态、细胞核DNA含量和DNA凝胶电泳法均证实了这一点。(2)As_2O_3对bax、bcl-x、c-myc和p53基因表达无明显影响，但在mRNA和蛋白水平均下调bcl-2基因的表达。(3)As_2O_3对NB4细胞和HL-60细胞的PML染色有明显的诱导作用。As2O_3处理NB4细胞后，NB4细胞中PML-RARα的微点状特征消失，而核周细胞质出现弥漫的PML染色。此外，低比例未经处理的NB4细胞显示PML阳性颗粒聚集在细胞质的隔室中。经As_2O_3处理后，这些细胞的百分率明显增加。在凋亡细胞中也观察到类似的PML染色模式。(4)全反式维甲酸预处理不影响As_2O_3诱导的细胞凋亡。这些结果提示，诱导细胞凋亡可能是三氧化二砷治疗作用的机制之一。此外，这种凋亡诱导独立于维甲酸途径发生，并可能至少部分地通过bcl2、PML-RARα和/或PML蛋白的调节而介导。
It has been shown recently in China that arsenic trioxide (As2O3) is a very effective treatment for acute promyelocytic leukemia (APL). APL patients resistant to all-trans retinoic acid (ATRA) and conventional chemotherapy can still respond to AS2O3. In this study, we addressed the possible cellular and molecular mechanisms of this treatment by using NB4 cells as a model. The results show that: (1) As2O3 triggers relatively specific NB4 cell apoptosis at micromolar concentration, as proved by morphology, histogramic related nuclear DNA contents, and DNA gel eletrophoresis. (2) As2O3 does not influence bax, bcl-x, c-myc, and p53 gene expression, but downregulates bcl-2 gene expression at both mRNA and protein levels. (3) As2O3 induces a significant modulation of the PML staining pattern in NB4 cells and HL-60 cells. The micropunctates characteristic of PML-RAR alpha in NB4 cells dissappear after treatment with As2O3, whereas a diffuse PML staining occurs in the perinuclear cytoplasmic region. In addition, a low percentage of untreated NB4 cells exhibits an accumulation of PML positive particles in a compartment of cytoplasm. The percentage of these cells can be significantly increased after As2O3 treatment. A similar PML staining pattern is observed in apoptotic cells. (4) ATRA pretreatment does not influence As2O3-induced apoptosis. These results suggest that induction of cell apoptosis can be one of the mechanisms of the therapeutic effect of As2O3. Moreover, this apoptosis induction occurs independently of the retinoid pathway and may be mediated, at least partly, through the modulation of bcl-2, as well as PML-RAR alpha and/ or PML proteins.