3-Deazaneplanocin A (DZNep), an inhibitor of S-adenosylmethionine-dependent methyltransferase, promotes erythroid differentiation.
3-Deazaneplanocin A (DZNep), an inhibitor of S-adenosylmethionine-dependent methyltransferase, promotes erythroid differentiation.
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DOI：
10.1074/jbc.m114.548651
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发表时间：
2014-03-21
期刊：
影响因子：
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通讯作者：
Harigae H
中科院分区：
文献类型：
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作者：
Fujiwara T;Saitoh H;Inoue A;Kobayashi M;Okitsu Y;Katsuoka Y;Fukuhara N;Onishi Y;Ishizawa K;Ichinohasama R;Harigae H
背景：S-腺苷甲硫氨酸依赖性甲基转移酶抑制剂 DZNep 以降解催化 H3K27 三甲基化的组蛋白甲基转移酶 EZH2 为目标。结果：DZNep 诱导红细胞相关基因，该基因可能与 EZH2 抑制没有直接关系，但可能部分与造血辅阻遏物 ETO2 蛋白水平降低有关。结论：DZNep具有诱导红系分化的能力。意义：我们的数据可用于血液疾病（包括贫血）的治疗应用。 EZH2 是多梳抑制复合物 2 (PRC2) 的核心成分，通过组蛋白 H3 Lys-27 三甲基化在转录抑制中发挥作用，并参与包括造血在内的各种生物过程。众所周知，3-deazaneplanocin A (DZNep)是一种S-腺苷甲硫氨酸依赖性甲基转移酶抑制剂，其目标是降解EZH2，优先诱导各种血液恶性肿瘤中的细胞凋亡，这表明EZH2可能是表观遗传治疗的新靶点。由于 PRC2 参与红细胞分化过程中 GATA-1 靶基因子集的表观遗传沉默，因此抑制 EZH2 可能会影响红细胞生成。为了探索这种可能性，我们评估了 DZNep 对红细胞生成的影响。通过联苯胺染色和定量 RT-PCR 分析对代表性红系相关基因（包括球蛋白）进行评估，DZNep 处理显着诱导 K562 细胞的红系分化。当我们评估 DZNep 对源自脐带血 CD34 阳性细胞的人原代成红细胞的影响时，如在 K562 细胞中观察到的那样，该治疗显着诱导红系相关基因，表明 DZNep 诱导红系分化。出乎意料的是，siRNA介导的EZH2敲低对红细胞相关基因的表达没有显着影响。 DZNep 处理的 K562 细胞的转录谱显示 SLC4A1 和 EPB42 显着上调，此前报道称它们是转录辅阻遏物 ETO2 的代表性靶标。此外，DZNep 处理降低了 ETO2 的蛋白水平。这些数据表明，DZNep 引起的红系分化可能与 EZH2 抑制没有直接关系，但可能部分与造血辅助抑制因子 ETO2 的蛋白水平降低有关。这些数据让我们更好地了解 DZNep 的作用机制，可用于治疗贫血等血液疾病。
Background: S-adenosylmethionine-dependent methyltransferase inhibitor, DZNep, targets the degradation of histone methyltransferase EZH2 that catalyzes H3K27 trimethylation. Results: DZNep induced erythroid-related genes, which may not be directly related to EZH2 inhibition but may be partly associated with reduced protein level of hematopoietic corepressor ETO2. Conclusion: DZNep has the capacity to induce erythroid differentiation. Significance: Our data may be exploited for therapeutic applications for hematological diseases, including anemia. EZH2, a core component of polycomb repressive complex 2 (PRC2), plays a role in transcriptional repression through histone H3 Lys-27 trimethylation and is involved in various biological processes, including hematopoiesis. It is well known that 3-deazaneplanocin A (DZNep), an inhibitor of S-adenosylmethionine-dependent methyltransferase that targets the degradation of EZH2, preferentially induces apoptosis in various hematological malignancies, suggesting that EZH2 may be a new target for epigenetic treatment. Because PRC2 participates in epigenetic silencing of a subset of GATA-1 target genes during erythroid differentiation, inhibition of EZH2 may influence erythropoiesis. To explore this possibility, we evaluated the impact of DZNep on erythropoiesis. DZNep treatment significantly induced erythroid differentiation of K562 cells, as assessed by benzidine staining and quantitative RT-PCR analysis for representative erythroid-related genes, including globins. When we evaluated the effects of DZNep in human primary erythroblasts derived from cord blood CD34-positive cells, the treatment significantly induced erythroid-related genes, as observed in K562 cells, suggesting that DZNep induces erythroid differentiation. Unexpectedly, siRNA-mediated EZH2 knockdown had no significant effect on the expression of erythroid-related genes. Transcriptional profiling of DZNep-treated K562 cells revealed marked up-regulation of SLC4A1 and EPB42, previously reported as representative targets of the transcriptional corepressor ETO2. In addition, DZNep treatment reduced the protein level of ETO2. These data suggest that erythroid differentiation by DZNep may not be directly related to EZH2 inhibition but may be partly associated with reduced protein level of hematopoietic corepressor ETO2. These data provide a better understanding of the mechanism of action of DZNep, which may be exploited for therapeutic applications for hematological diseases, including anemia.