Division of Radiation and Cancer Biology, Department of Radiation Oncology, Center for Clinical Sciences Research, Stanford University, Stanford, CA 94303-5152, USA.
Mol Cell Biol. 2010 Jan;30(1):344-53. doi: 10.1128/MCB.00444-09.
The hypoxia-inducible transcription factors (HIFs) directly and indirectly mediate cellular adaptation to reduced oxygen tensions. Recent studies have shown that the histone demethylase genes JMJD1A, JMJD2B, and JARID1B are HIF targets, suggesting that HIFs indirectly influence gene expression at the level of histone methylation under hypoxia. In this study, we identify a subset of hypoxia-inducible genes that are dependent on JMJD1A in both renal cell and colon carcinoma cell lines. JMJD1A regulates the expression of adrenomedullin (ADM) and growth and differentiation factor 15 (GDF15) under hypoxia by decreasing promoter histone methylation. In addition, we demonstrate that loss of JMJD1A is sufficient to reduce tumor growth in vivo, demonstrating that histone demethylation plays a significant role in modulating growth within the tumor microenvironment. Thus, hypoxic regulation of JMJD1A acts as a signal amplifier to facilitate hypoxic gene expression, ultimately enhancing tumor growth.
缺氧诱导转录因子 (HIFs) 直接或间接介导细胞对低氧张力的适应。最近的研究表明,组蛋白去甲基化酶基因 JMJD1A、JMJD2B 和 JARID1B 是 HIF 的靶标,这表明 HIFs 在低氧条件下通过组蛋白甲基化水平间接影响基因表达。在这项研究中,我们在肾细胞和结肠癌细胞系中确定了一组依赖于 JMJD1A 的缺氧诱导基因。JMJD1A 通过降低启动子组蛋白甲基化来调节缺氧条件下肾上腺髓质素 (ADM) 和生长分化因子 15 (GDF15) 的表达。此外,我们证明 JMJD1A 的缺失足以减少体内肿瘤的生长,表明组蛋白去甲基化在调节肿瘤微环境中的生长中起着重要作用。因此,JMJD1A 的缺氧调节作用充当信号放大器,促进缺氧基因表达,最终增强肿瘤生长。