Institute of Ageing Research, School of Medicine, Hangzhou Normal University, Hangzhou, China.
Department of Radiotherapy, Zhejiang Cancer Hospital, Hangzhou, China.
Genes Chromosomes Cancer. 2020 Feb;59(2):73-83. doi: 10.1002/gcc.22802. Epub 2019 Sep 3.
Hypoxia-induced epithelial-mesenchymal transition (EMT) involves the interplay between chromatin modifiers histone deacetylase 3 (HDAC3) and WDR5. The histone mark histone 3 lysine 4 acetylation (H3K4Ac) is observed in the promoter regions of various EMT marker genes (eg, CDH1 and VIM). To further define the genome-wide location of H3K4Ac, a chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq) analysis was performed using a head and neck squamous cell carcinoma (HNSCC) FaDu cell line under normoxia and hypoxia. H3K4Ac was found to be located mainly around the transcription start site. Coupled with analysis of gene expression by RNA sequencing and using a HDAC3 knockdown cell line, 10 new genes (BMI1, GLI1, SMO, FOXF1, SIRT2, etc) that were labeled by H3K4Ac and regulated by HDAC3 were identified. Overexpression or knockdown of GLI1/SMO increased or repressed the in vitro migration and invasion activity in OECM-1/FaDu cells, respectively. In HNSCC patients, coexpression of GLI1 and SMO in primary tumors correlated with metastasis. Our results identify new EMT marker genes that may play a significant role in hypoxia-induced EMT and metastasis and further provide diagnostic and prognostic implications.
缺氧诱导的上皮-间充质转化（EMT）涉及染色质修饰酶组蛋白去乙酰化酶 3（HDAC3）和 WDR5 之间的相互作用。组蛋白标记物组蛋白 3 赖氨酸 4 乙酰化（H3K4Ac）存在于各种 EMT 标记基因（如 CDH1 和 VIM）的启动子区域。为了进一步定义 H3K4Ac 的全基因组位置，使用头颈部鳞状细胞癌（HNSCC）FaDu 细胞系在常氧和缺氧条件下进行了染色质免疫沉淀结合大规模平行 DNA 测序（ChIP-seq）分析。发现 H3K4Ac 主要位于转录起始位点附近。与 RNA 测序分析的基因表达以及使用 HDAC3 敲低细胞系相结合，鉴定出 10 个新的基因（BMI1、GLI1、SMO、FOXF1、SIRT2 等），这些基因被 H3K4Ac 标记并受 HDAC3 调节。GLI1/SMO 的过表达或敲低分别增加或抑制了 OECM-1/FaDu 细胞的体外迁移和侵袭活性。在 HNSCC 患者中，原发肿瘤中 GLI1 和 SMO 的共表达与转移相关。我们的研究结果确定了新的 EMT 标记基因，它们可能在缺氧诱导的 EMT 和转移中发挥重要作用，并进一步提供了诊断和预后意义。
