Abstract：
The critical importance of circular RNAs (circRNAs) in human cancers, including cervical cancer (CC), has been discovered in recent years. However, the function and mechanism of hsa_circ_0000069 (circ_0000069) in CC have been fully understood. The expression levels of circ_0000069, microRNAs (miR-1270, miR-1276 and miR-620) and cytoplasmic polyadenylation element binding protein 4 (CPEB4) mRNA were detected by quantitative real time polymerase chain reaction (qRT-PCR). Cell Counting Kit-8 (CCK-8), 5-ethynyl-2\'-deoxyuridine (EdU), flow cytometry, wound healing, transwell and tube formation assays were used to clarify the effects of circ_0000069 on the functional behaviors of CC cells. The binding relationships among miR-1270, circ_0000069 and CPEB4 were detected by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. A xenograft tumor model was established to explore the effect of circ_0000069 on tumor growth in vivo. Circ_0000069 was upregulated in CC clinical samples and cell lines, and its expression was associated with the clinical stage of CC patients. Circ_0000069 knockdown significantly decreased cell proliferation, invasion, migration, and tube formation and increased cell apoptosis in vitro. Moreover, miR-1270 was a direct target of circ_0000069, and CPEB4 was the downstream target of miR-1270. Knockdown of miR-1270 reversed the inhibitory effect of circ_0000069 knockdown on CC progression, and CPEB4 overexpression overturned the effect of miR-1270 on CC progression. In xenograft experiments, the oncogenic effect of circ_0000069 on tumor growth was verified. Altogether, circ_0000069 adsorbed miR-1270 to upregulate CPEB4 expression, thereby promoting the malignant phenotypes of CC cells. Circ_0000069 might be a potential target for treatment of CC.
摘要：
环状RNA（circularRNAs，circRNAs）在人类癌症中的重要性，包括宫颈癌（CC），近年来被发现。然而,hsa_circ_0000069(circ_0000069)在CC中的作用和机制已经被充分理解。采用实时定量聚合酶链反应(qRT-PCR)检测circ_0000069、微小RNA(miR-1270、miR-1276和miR-620)和胞质多聚腺苷酸化元件结合蛋白4(CPEB4)mRNA的表达水平。细胞计数套件-8（CCK-8），5-乙炔基-2'-脱氧尿苷（EdU），流式细胞术,伤口愈合，transwell和试管形成试验用于阐明circ_0000069对CC细胞功能行为的影响。通过双荧光素酶报告基因和RNA免疫沉淀(RIP)检测miR-1270、circ_0000069和CPEB4之间的结合关系。建立异种移植肿瘤模型以探讨circ_0000069对体内肿瘤生长的影响。Circ_0000069在CC临床样品和细胞系中上调，其表达与CC患者的临床分期有关。Circ_0000069敲低显著降低细胞增殖，入侵,迁移,和试管形成和体外细胞凋亡增加。此外，miR-1270是circ_0000069的直接靶标,CPEB4是miR-1270的下游靶标。miR-1270的敲低逆转了circ_0000069敲低对CC进展的抑制作用，和CPEB4的过表达推翻了miR-1270对CC进展的影响。在异种移植实验中,证实了circ_0000069对肿瘤生长的致癌作用。总之,circ_0000069吸附miR-1270上调CPEB4表达，从而促进CC细胞的恶性表型。Circ_0000069可能是治疗CC的潜在靶标。
