Many circRNAs have been reported to play important roles in cancer development and have the potential to serve as a novel class of biomarkers for clinical diagnosis. However, the role of circRNAs in esophageal carcinoma (EC) remains unclear. In the current study, we investigated the potential role of circPVT1 in esophageal carcinoma. Quantitative real-time PCR was performed to detect circPVT1 levels. CircPVT1-specific siRNA or plasmids were used to knock down or overexpression the target RNA. Hoechst Staining was implemented to evaluate the ratio of cell apoptosis. Transwell migration assays were carried out to study the effects of circPVT1 on esophageal squamous cell carcinoma cell invasion. RegRNA 2.0 was used for bioinformatics analysis. The expression levels of Pax-4, Pax-6, PPARα and PPAR-γ were assessed using Western blot. In the present study, we demonstrated a significant up-regulation of circPVT1 levels in EC tissues and cancer cell lines. The levels of circPVT1 decreased significantly when the cells were maintained to over-confluence. These results suggested a potential role for circPVT1 in cell proliferation. In addition, overexpressing circPVT1 in TE-10 cell promoted invasive ability of cancer cell. In contrast, siRNA knockdown of circPVT1 inhibited this phenomenon, leading to increased apoptosis levels of TE-10 cell. What’s more, miR-4663 had the effect of inhibiting tumor growth by downregulated Paxs and upregulated PPARs. Whereas, after the addition of circPVT1, this effect no longer worked, suggesting that circPVT1 may affect the malignancy of the tumor by affecting miRNA and regulating the levels of Paxs and PPARs. Collectively, our study reveals a critical role for circPVT1 in esophageal carcinoma, which may provide new insights of this circRNA as a biomarker for the diagnosis and treatment target of EC.

中文翻译：

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circPVT1作为食管癌增殖因子和治疗靶点的潜在作用

据报道，许多 circRNA 在癌症发展中发挥重要作用，并有可能作为一类用于临床诊断的新型生物标志物。然而，circRNA在食管癌（EC）中的作用仍不清楚。在目前的研究中，我们调查了 circPVT1 在食管癌中的潜在作用。进行定量实时 PCR 以检测 circPVT1 水平。CircPVT1 特异性 siRNA 或质粒用于敲低或过表达靶 RNA。实施赫斯特染色以评估细胞凋亡的比率。进行 Transwell 迁移试验以研究 circPVT1 对食管鳞状细胞癌细胞侵袭的影响。RegRNA 2.0 用于生物信息学分析。使用蛋白质印迹评估 Pax-4、Pax-6、PPARα 和 PPAR-γ 的表达水平。在本研究中，我们证明了 EC 组织和癌细胞系中 circPVT1 水平的显着上调。当细胞保持过度融合时，circPVT1的水平显着下降。这些结果表明circPVT1在细胞增殖中的潜在作用。此外，在 TE-10 细胞中过表达 circPVT1 可促进癌细胞的侵袭能力。相比之下，circPVT1 的 siRNA 敲低抑制了这种现象，导致 TE-10 细胞的凋亡水平增加。更重要的是，miR-4663通过下调Paxs和上调PPARs具有抑制肿瘤生长的作用。而在加入circPVT1后，这种作用不再起作用，这表明circPVT1可能通过影响miRNA和调节Paxs和PPARs的水平来影响肿瘤的恶性程度。集体，