Abstract This study was designed to illustrate the function and role of PCAT1 in CCA. The relative expression was confirmed by RT-qPCR and western blot. The biological function of PCAT1 was evaluated by CCK8, EdU, colony formation, wound healing, transwell, and subcutaneous tumor formation assays. Protein levels of EMT markers were measured by western blot. The binding relationship was predicted by JASPAR and starBase. The binding of YY1 to PCAT1 promoter was assessed by ChIP and luciferase reporter. The binding capacity between miR-216a-3p and PCAT1 as well as BCL3 was assessed by luciferase reporter and AGO2-RIP assays. In this study, we found that PCAT1 was up-regulated in CCA tissues and cells, and the PCAT1 overexpression was associated with poor prognosis. Moreover, PCAT1 was assessed as an independent risk factor of prognosis for CCA patients. Amplified PCAT1 was found to promote tumor proliferation, migration, invasion and EMT process, whereas PCAT1 knockdown inhibited these malignant phenotypes. Mechanistically, PCAT1 was predominantly localized in the cytoplasm and competitively bound miR-216a-3p to increase BCL3 expression. In addition, PCAT1 was activated by transcription factor YY1. This study revealed that PCAT1 acted as an oncogene in CCA, and the YY1/PCAT1/miR-216a-3p/BCL3 axis exhibited critical functions in CCA progression.

中文翻译：

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转录因子YY1诱导的PCAT1通过海绵miR-216a-3p上调癌基因BCL3促进胆管癌增殖、迁移和侵袭

摘要 本研究旨在阐明 PCAT1 在 CCA 中的功能和作用。RT-qPCR 和蛋白质印迹证实了相对表达。PCAT1 的生物学功能通过 CCK8、EdU、集落形成、伤口愈合、transwell 和皮下肿瘤形成测定进行评估。EMT 标记的蛋白质水平通过蛋白质印迹测量。结合关系由JASPAR和starBase预测。YY1 与 PCAT1 启动子的结合通过 ChIP 和荧光素酶报告基因进行评估。miR-216a-3p 和 PCAT1 以及 BCL3 之间的结合能力通过荧光素酶报告基因和 AGO2-RIP 测定进行评估。在本研究中，我们发现 PCAT1 在 CCA 组织和细胞中上调，并且 PCAT1 过表达与不良预后相关。而且，PCAT1 被评估为 CCA 患者预后的独立危险因素。发现扩增的 PCAT1 促进肿瘤增殖、迁移、侵袭和 EMT 过程，而 PCAT1 敲低抑制了这些恶性表型。从机制上讲，PCAT1 主要定位于细胞质中并竞争性结合 miR-216a-3p 以增加 BCL3 表达。此外，PCAT1 被转录因子 YY1 激活。该研究表明 PCAT1 在 CCA 中充当致癌基因，YY1/PCAT1/miR-216a-3p/BCL3 轴在 CCA 进展中表现出关键功能。PCAT1 主要位于细胞质中并竞争性结合 miR-216a-3p 以增加 BCL3 表达。此外，PCAT1 被转录因子 YY1 激活。该研究表明，PCAT1 在 CCA 中充当癌基因，YY1/PCAT1/miR-216a-3p/BCL3 轴在 CCA 进展中表现出关键功能。PCAT1 主要位于细胞质中并竞争性结合 miR-216a-3p 以增加 BCL3 表达。此外，PCAT1 被转录因子 YY1 激活。该研究表明，PCAT1 在 CCA 中充当癌基因，YY1/PCAT1/miR-216a-3p/BCL3 轴在 CCA 进展中表现出关键功能。