Das Amitabh, Chai Jin Choul, Jung Kyoung Hwa, Das Nando Dulal, Kang Sung Chul, Lee Young Seek, Seo Hyemyung, Chai Young Gyu
Department of Bionanotechnology, Hanyang University, Seoul 133-791, Republic of Korea.
Department of Molecular & Life Science, Hanyang University, 1271 Sa 3-dong, Ansan 426-791, Gyeonggi-do, Republic of Korea.
Exp Cell Res. 2014 Nov 1;328(2):361-78. doi: 10.1016/j.yexcr.2014.08.029. Epub 2014 Sep 1.
JMJD2A is a lysine trimethyl-specific histone demethylase that is highly expressed in a variety of tumours. The role of JMJD2A in tumour progression remains unclear. The objectives of this study were to identify JMJD2A-regulated genes and understand the function of JMJD2A in p53-null neuroectodermal stem cells (p53(-/-) NE-4Cs). We determined the effect of LPS as a model of inflammation in p53(-/-) NE-4Cs and investigated whether the epigenetic modifier JMJD2A alter the expression of tumourigenic inflammatory genes. Global gene expression was measured in JMJD2A knockdown (kd) p53(-/-) NE-4Cs and in LPS-stimulated JMJD2A-kd p53(-/-) NE-4C cells. JMJD2A attenuation significantly down-regulated genes were Cdca2, Ccnd2, Ccnd1, Crebbp, IL6rα, and Stat3 related with cell cycle, proliferation, and inflammatory-disease responses. Importantly, some tumour-suppressor genes including Dapk3, Timp2 and TFPI were significantly up-regulated but were not affected by silencing of the JMJD2B. Furthermore, we confirmed the attenuation of JMJD2A also down-regulated Cdca2, Ccnd2, Crebbp, and Rest in primary NSCs isolated from the forebrains of E15 embryos of C57/BL6J mice with effective p53 inhibitor pifithrin-α (PFT-α). Transcription factor (TF) motif analysis revealed known binding patterns for CDC5, MYC, and CREB, as well as three novel motifs in JMJD2A-regulated genes. IPA established molecular networks. The molecular network signatures and functional gene-expression profiling data from this study warrants further investigation as an effective therapeutic target, and studies to elucidate the molecular mechanism of JMJD2A-kd-dependent effects in neuroectodermal stem cells should be performed.
JMJD2A是一种赖氨酸三甲基特异性组蛋白去甲基化酶,在多种肿瘤中高表达。JMJD2A在肿瘤进展中的作用仍不清楚。本研究的目的是鉴定受JMJD2A调控的基因,并了解JMJD2A在p53基因缺失的神经外胚层干细胞(p53(-/-)NE-4C细胞)中的功能。我们确定了脂多糖(LPS)作为p53(-/-)NE-4C细胞炎症模型的作用,并研究了表观遗传修饰因子JMJD2A是否会改变致瘤性炎症基因的表达。在敲低(kd)JMJD2A的p53(-/-)NE-4C细胞以及LPS刺激的敲低JMJD2A的p53(-/-)NE-4C细胞中测量全局基因表达。JMJD2A表达减弱显著下调的基因有Cdca2、Ccnd2、Ccnd1、Crebbp、IL6rα和与细胞周期、增殖及炎症疾病反应相关的Stat3。重要的是,一些肿瘤抑制基因,包括Dapk3、Timp2和TFPI显著上调,但不受JMJD2B沉默的影响。此外,我们证实,在使用有效的p53抑制剂pifithrin-α(PFT-α)从C57/BL6J小鼠E15胚胎前脑分离的原代神经干细胞中,JMJD2A表达减弱也下调了Cdca2、Ccnd2、Crebbp和Rest。转录因子(TF)基序分析揭示了CDC5、MYC和CREB的已知结合模式,以及JMJD2A调控基因中的三个新基序。IPA建立了分子网络。本研究的分子网络特征和功能基因表达谱数据作为一种有效的治疗靶点值得进一步研究,并且应该开展研究以阐明JMJD2A敲低在神经外胚层干细胞中依赖性效应的分子机制。