Mol Cancer|张晓晶团队揭示成骨肉瘤肿瘤发生和顺铂耐药环状RNA的ceRNA机制

2022年8月3日 0条评论 187次阅读 0人点赞

最新细胞功能及机制文献分享

据报道，环状RNA（circRNA）可通过与miRNA结合来调节基因表达，即经典ceRNA机制，其参与多种癌症发病机制，如乳腺癌、胆管癌和胶质母细胞瘤。然而，关于circDOCK1表达及其在成骨肉瘤（OS，也称为骨肉瘤）中的生物学功能仍存在许多未知。2021年12月7日，辽宁省肿瘤医院研究所张晓晶团队在Molecular Cancer上发表了题为“CircDOCK1 promotes the tumorigenesis and cisplatin resistance of osteogenic sarcoma via the miR-339-3p/IGF1R axis”的研究论文。在本研究中，团队通过circRNA微阵列分析和定量实时PCR（qRT-PCR）鉴定了OS细胞系和组织中差异表达的circRNA，并将回补实验、RNA免疫沉淀（RIP）、RNA pulldown分析以及双荧光素酶分析与体内外模型结合，从多层次、多角度验证了CircDOCK1通过miR-339-3p/IGF1R轴调节OS进展并调节顺铂敏感性。最终证实，circDOCK1/miR-339-3p/IGF1R轴可能是OS的关键机制和治疗靶点。

OS是一种起源于间充质细胞的原发性骨肉瘤，常发生于儿童和青年，大约25%的患者可检测到转移灶，最常见于肺部。尽管在当前的治疗方案中使用了放疗、化疗和手术的组合，但晚期OS的临床结果仍令人不满意。目前已发现，circRNAs主要通过三种机制发挥作用：（1）亲本基因表达的顺式调控；（2）作为microRNA（miRNA）海绵调节基因表达（即作为竞争性内源RNA，简称ceRNA）；（3）与RNA结合蛋白（RBP）形成复合物。

在本研究中，团队基于微阵列分析和qRT-PCR，发现circDOCK1（即hsa_circ_0020378，位于染色体10:128594022-128,926,028，长2848nt）在OS细胞系和组织中高表达，可增强OS细胞迁移、增殖和侵袭，这与其过表达增加了体内致癌性和体外恶性转化结论一致。在U2OS和MG63细胞系中，circDOCK1通过miR-339-3p的海绵作用调节IGF1R来调节肿瘤进展。此外，在U2OS/DDP和MG63/DDP细胞系中，顺铂敏感性由circDOCK1通过miR-339-3p/IGF1R轴调节。至此，团队提出circDOCK1参与OS进展的分子机制为通过与miR-339-3p的竞争性结合调节IGF1R表达，从而促进癌发生和化疗耐药。

《Mol Cancer|张晓晶团队揭示成骨肉瘤肿瘤发生和顺铂耐药环状RNA的ceRNA机制》

图本文部分实验结果。

期刊及DOI号

Mol Cancer. 2021 Dec 7.

doi: 10.1186/s12943-021-01453-0.

题目

CircDOCK1 promotes the tumorigenesis and cisplatin resistance of osteogenic sarcoma via the miR-339-3p/IGF1R axis

摘要

背景：Circular RNAs (circRNAs), a class of noncoding RNAs (ncRNAs), may modulate gene expression by bind-ing to miRNAs. Additionally, recent studies show that circRNAs participate in some pathological processes. However, there is a large gap in the knowledge about circDOCK1 expression and its biological functions in osteogenic sarcoma (OS).

方法：Differentially expressed circRNAs in OS cell lines and tissues were identified by circRNA microarray analysis and quantitative real-time PCR (qRT–PCR). To explore the actions of circDOCK1 in vivo and in vitro, circDOCK1 was knocked down or overexpressed. To assess the binding and regulatory associations among miR-339-3p, circDOCK1 and IGF1R, we performed rescue experiments, RNA immunoprecipitation (RIP), RNA pulldown assays and dual-lucif-erase assays. Moreover, we performed apoptosis assays to reveal the regulatory effects of the circDOCK1/miR-339-3p/IGF1R axis on cisplatin sensitivity.

结果：CircDOCK1 expression remained stable in the cytoplasm and was higher in OS tissues and cells than in the corresponding controls. Overexpression of circDOCK1 increased oncogenicity in vivo and malignant transforma-tion in vitro. In the U2OS and MG63 cell lines, circDOCK1 modulated tumor progression by regulating IGF1R through sponging of miR-339-3p. Additionally, in the U2OS/DDP and MG63/DDP cell lines, cisplatin sensitivity was regulated by circDOCK1 via the miR-339-3p/IGF1R axis.

结论：CircDOCK1 can promote progression and regulate cisplatin sensitivity in OS via the miR-339-3p/IGF1R axis. Thus, the circDOCK1/miR-339-3p/IGF1R axis may be a key mechanism and therapeutic target in OS.

关键词：circDOCK1, miR-339-3p, IGF1R, OS, Cisplatin resistance