Overexpression of chromodomain helicase DNA binding protein 5 (CHD5) inhibits cell proliferation and induces cell cycle arrest and apoptosis in chronic myeloid leukemia.
Overexpression of chromodomain helicase DNA binding protein 5 (CHD5) inhibits cell proliferation and induces cell cycle arrest and apoptosis in chronic myeloid leukemia.
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慢性粒细胞白血病中染色质结构域解旋酶 DNA 结合蛋白 5 (CHD5) 的过度表达抑制细胞增殖并诱导细胞周期停滞和细胞凋亡
DOI：
10.21037/tcr-20-2276
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发表时间：
2021-03
影响因子：
0.9
通讯作者：
Zhao R
中科院分区：
文献类型：
--
作者：
Xiong S;Yan Q;Peng Y;Huang S;Zhao R
背景染色体结构域解旋酶DNA结合蛋白5（Chromodomain helicase DNA binding protein 5，CHD 5）是一种肿瘤抑制蛋白，我们的前期工作表明CHD 5在人类慢性粒细胞白血病（chronic myeloid leukemia，CML）中表观遗传学失活。本研究旨在探讨其过表达对CML肿瘤发生的影响。方法采用逆转录聚合酶链反应（RT-PCR）和蛋白质印迹法（Western blotting）检测CHD 5在CML细胞系中的表达。通过CRISPR/dCas 9-SAM系统在两种CML细胞系中激活内源性CHD 5表达。进行体外细胞功能实验，包括增殖、集落形成、凋亡、自噬、衰老和分化测定。此外，在裸鼠异种移植模型中评价体内致瘤性。结果与正常骨髓单个核细胞相比，CML细胞系中CHD 5表达下调。激活CHD 5后细胞增殖明显受到抑制。此外，CHD 5的过表达可诱导CML细胞发生G2/M期阻滞和凋亡。在肿瘤异种移植小鼠模型中，发现CHD 5恢复显著抑制肿瘤生长。与对照组相比，CHD 5过表达可增加p21和cdc 2磷酸化的表达，而降低Cyclin B1的蛋白水平。此外，实验表明，在CML细胞中，CHD 5的上调激活caspase-3，而抗凋亡蛋白Bcl-2的表达降低。结论CHD 5在CML细胞增殖、细胞周期阻滞和凋亡中发挥抗肿瘤作用。
Background Chromodomain helicase DNA binding protein 5 (CHD5) was reported to be a tumor suppressor and our previous work showed CHD5 was epigenetically inactivated in human chronic myeloid leukemia (CML). This study aimed to investigate the effect of its overexpression on CML tumorigenesis. Methods Quantitative reverse-transcriptase PCR and Western blotting analysis were used to detect the expression of CHD5 in human CML cell lines. The endogenous CHD5 expression was activated in two CML cell lines by CRISPR/dCas9-SAM system. In vitro cell function experiments were performed including proliferation, colony formation, apoptosis, autophagy, senescence and differentiation assays. Furthermore, tumorigenicity was evaluated in vivo in nude mice xenograft model. Results CHD5 was down-regulated in CML cell lines compare to normal bone marrow mononuclear cells (MCs). Cell proliferation after activating CHD5 was significantly inhibited. Moreover, overexpression of CHD5 induced G2/M phase arrest and apoptosis in CML cells. In a tumor xenograft mouse model, CHD5 restoration was found to sharply repress tumor growth. Compared with the control group, overexpression of CHD5 enhanced the expression of p21 and cdc2 phosphorylation, whereas decreased the protein level of Cyclin B1. Furthermore, experiments revealed that up-regulation of CHD5 activated caspase-3, while anti-apoptosis protein Bcl-2 expression was reduced in CML cells. Conclusions CHD5 plays a role of anti-tumorigenic effects involved in CML cell proliferation, cell cycle arrest and apoptosis.