Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Hidaka, Saitama, 350-1241, Japan; Department of Obstetrics and Gynecology, Juntendo University School of Medicine, Tokyo, 113-8421, Japan.
Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Hidaka, Saitama, 350-1241, Japan.
Biochem Biophys Res Commun. 2021 Apr 9;548:204-210. doi: 10.1016/j.bbrc.2021.02.066. Epub 2021 Feb 26.
Estrogen-responsive endometrial cancer (EC) is prevalent in uterine cancer. Its precise molecular mechanisms remain to be elucidated partly because of limited availability of estrogen-sensitive EC models recapitulating clinical pathophysiology. We previously established EC patient-derived cancer cell (EC-PDC) spheroid culture with high expression of estrogen receptor α (ERα). Using this EC-PDC, we study the transcriptional regulation and function of estrogen-responsive finger protein (Efp), a prototypic tripartite motif (TRIM) protein that modulates protein degradation and RNA processing. Intense estrogen-dependent EFP mRNA induction and high ERα occupancy to EFP estrogen responsive element (ERE) were observed in EC-PDC. Luciferase reporter gene assay showed that the ERE facilitates EFP transcriptional activity estrogen-dependently. siRNA-mediated Efp silencing in EC-PDC resulted in suppressed spheroid proliferation and altered gene expression profile, featuring downregulation of genes related to cell cycle (e.g., CDK6) and inflammation/immune responses (e.g., IL10RA, IL26, and IL6ST) while unaffected expression of cancer stemness-related markers. Taken together, EC-PDC spheroid culture is a powerful EC tool that enables to dissect Efp-mediated ERα signaling pathways as an estrogen-sensitive EC model. This study provides an insight into alternative EC therapeutic strategies targeting ERα-Efp axis.
雌激素反应性子宫内膜癌（EC）在子宫癌中较为常见。由于缺乏能够重现临床病理生理学的雌激素敏感型 EC 模型，其确切的分子机制仍有待阐明。我们之前建立了具有高表达雌激素受体α（ERα）的 EC 患者来源的癌细胞（EC-PDC）球体培养。使用这种 EC-PDC，我们研究了雌激素反应性手指蛋白（Efp）的转录调控和功能，Efp 是一种典型的三联基序（TRIM）蛋白，可调节蛋白质降解和 RNA 加工。在 EC-PDC 中观察到强烈的雌激素依赖性 EFP mRNA 诱导和高 ERα 占据 EFP 雌激素反应元件（ERE）。荧光素酶报告基因检测表明 ERE 促进 EFP 的转录活性依赖于雌激素。在 EC-PDC 中通过 siRNA 介导的 Efp 沉默导致球体增殖受到抑制和基因表达谱改变，表现为细胞周期相关基因（如 CDK6）和炎症/免疫反应相关基因（如 IL10RA、IL26 和 IL6ST）下调，而癌症干性相关标记物的表达不受影响。总之，EC-PDC 球体培养是一种强大的 EC 工具，可用于剖析 Efp 介导的 ERα 信号通路作为雌激素敏感型 EC 模型。这项研究为针对 ERα-Efp 轴的替代 EC 治疗策略提供了新的思路。
