McArdle Laboratory for Cancer Research, Department of Oncology and Carbone Comprehensive Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin, USA.
Department of Human Oncology, University of Wisconsin-Madison, Madison, Wisconsin, USA.
Mol Cell Biol. 2022 Oct 20;42(10):e0019122. doi: 10.1128/mcb.00191-22. Epub 2022 Aug 29.
Phosphorylation of estrogen receptor α (ER) at serine 118 (pS118-ER) is induced by estrogen and is the most abundant posttranslational mark associated with a transcriptionally active receptor. Cistromic analysis of pS118-ER from our group revealed enrichment of the GRHL2 motif near pS118-ER binding sites. In this study, we used cistromic and transcriptomic analyses to interrogate the relationship between GRHL2 and pS118-ER. We found that GRHL2 is bound to chromatin at pS118-ER/GRHL2 co-occupancy sites prior to ligand treatment, and GRHL2 binding is required for maximal pS118-ER recruitment. pS118-ER/GRHL2 co-occupancy sites were enriched at active enhancers marked by H3K27ac and H3K4me1, along with FOXA1 and p300, compared to sites where each factor binds independently. Transcriptomic analysis yielded four subsets of ER/GRHL2-coregulated genes revealing that GRHL2 can both enhance and antagonize E2-mediated ER transcriptional activity. Gene ontology analysis indicated that coregulated genes are involved in cell migration. Accordingly, knockdown of GRHL2, combined with estrogen treatment, resulted in increased cell migration but no change in proliferation. These results support a model in which GRHL2 binds to selected enhancers and facilitates pS118-ER recruitment to chromatin, which then results in differential activation and repression of genes that control estrogen-regulated ER-positive breast cancer cell migration.
雌激素受体 α（ER）丝氨酸 118 位磷酸化（pS118-ER）是由雌激素诱导的，是与转录活性受体最相关的翻译后修饰标记。我们小组的 cistromic 分析显示，pS118-ER 结合位点附近富含 GRHL2 基序。在这项研究中，我们使用 cistromic 和转录组学分析来探究 GRHL2 和 pS118-ER 之间的关系。我们发现，在配体处理之前，GRHL2 就已经结合到 pS118-ER/GRHL2 共占据的染色质上，并且 GRHL2 的结合对于最大程度地募集 pS118-ER 是必需的。与每个因子独立结合的位点相比，pS118-ER/GRHL2 共占据的位点在由 H3K27ac 和 H3K4me1 标记的活跃增强子上富集，并且还与 FOXA1 和 p300 一起富集。转录组学分析产生了四个 ER/GRHL2 共调节基因子集，揭示了 GRHL2 既可以增强也可以拮抗 E2 介导的 ER 转录活性。GO 分析表明，共调节基因参与细胞迁移。因此，GRHL2 的敲低，结合雌激素处理，导致细胞迁移增加，但增殖没有变化。这些结果支持了一个模型，即 GRHL2 结合到选定的增强子上，并促进 pS118-ER 募集到染色质上，这继而导致控制雌激素调节的 ER 阳性乳腺癌细胞迁移的基因的差异激活和抑制。
