Department of Thoracic Surgery, The Affiliated Xiangshan Hospital of Wenzhou Medial University, Ningbo, China.
Thorac Cancer. 2022 Oct;13(20):2867-2878. doi: 10.1111/1759-7714.14631. Epub 2022 Sep 3.
Many circular RNAs (circRNAs) have been identified as potential targets for cancer therapy. However, the role of circ_0002476 in non-small cell lung cancer (NSCLC) progression has not been explored.
The expression levels of circ_0002476, microRNA (miR)-1182, and mitochondrial transcription factor A (TFAM) were detected by quantitative real-time polymerase chain reaction. Cell functions were measured by cell counting kit 8 assay, EdU assay, colony formation assay, flow cytometry and transwell assay. Mitochondrial DNA (mtDNA) damage was assessed by measuring mtDNA copy number and transcript levels of ND1 and ATP6. Protein expression was examined by western blot. The interaction between miR-1182 and circ_0002476 or TFAM was detected by dual-luciferase reporter assay and RNA pull-down assay. Animal experiments were performed to explore circ_0002476 role in vivo. Exosomes (Exs) were extracted and identified by transmission electron microscopy and nanoparticle tracking analysis.
Circ_0002476 was overexpressed in NSCLC tissues and cells. Circ_0002476 knockdown suppressed NSCLC cell proliferation and invasion, while promoted apoptosis and mtDNA damage. Circ_0002476 could sponge miR-1182, and miR-1182 inhibitor reversed the influence induced by circ_0002476 knockdown. Moreover, TFAM was targeted by miR-1182, and miR-1182 hindered NSCLC cell progression by regulating TFAM. Additionally, circ_0002476 silencing could reduce NSCLC tumor growth by miR-1182/TFAM. Further analyzed showed that Exs were involved in the transport of circ_0002476 between cells.
Taken together, our findings suggested that circ_0002476 might be a potential molecular target for NSCLC treatment.
许多环状 RNA（circRNA）已被鉴定为癌症治疗的潜在靶点。然而，circ_0002476 在非小细胞肺癌（NSCLC）进展中的作用尚未被探索。
通过实时定量聚合酶链反应检测 circ_0002476、microRNA（miR）-1182 和线粒体转录因子 A（TFAM）的表达水平。通过细胞计数试剂盒 8 测定、EdU 测定、集落形成测定、流式细胞术和 Transwell 测定来测量细胞功能。通过测量线粒体 DNA（mtDNA）拷贝数和 ND1 和 ATP6 的转录水平来评估 mtDNA 损伤。通过 Western blot 检测蛋白表达。通过双荧光素酶报告基因检测和 RNA 下拉实验检测 miR-1182 与 circ_0002476 或 TFAM 的相互作用。通过动物实验探索 circ_0002476 在体内的作用。通过透射电子显微镜和纳米颗粒跟踪分析提取和鉴定外泌体（Exs）。
circ_0002476 在 NSCLC 组织和细胞中高表达。circ_0002476 敲低抑制 NSCLC 细胞增殖和侵袭，促进凋亡和 mtDNA 损伤。circ_0002476 可以海绵 miR-1182，而 miR-1182 抑制剂逆转了 circ_0002476 敲低引起的影响。此外，TFAM 是 miR-1182 的靶标，miR-1182 通过调节 TFAM 来抑制 NSCLC 细胞的进展。此外，circ_0002476 沉默可以通过 miR-1182/TFAM 减少 NSCLC 肿瘤的生长。进一步分析表明，Exs 参与了 circ_0002476 在细胞间的运输。
总之，我们的研究结果表明，circ_0002476 可能是 NSCLC 治疗的潜在分子靶点。
