环状 RNA-PITX1 通过 miR-615-5p 调控 ETS1 表达促进非小细胞肺癌进展。

Circ-PITX1 promotes non-small-cell lung cancer progression through regulating ETS1 expression via miR-615-5p.

机构信息

Department of Pulmonary and Critical Care Medicine, Zhejiang Jinhua Guangfu Tumor Hospital, Jinhua, China.

出版信息

Thorac Cancer. 2024 Sep;15(27):1946-1957. doi: 10.1111/1759-7714.15414. Epub 2024 Aug 13.

DOI:10.1111/1759-7714.15414

PMID:39138880

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11463087/

Abstract

BACKGROUND

Circular RNAs (circRNAs), produced by reverse splicing, act as important players in human cancers. We aimed to assess the biological functions of circRNA pituitary homeobox 1 (circ-PITX1) in non-small-cell lung cancer (NSCLC).

METHODS

qRT-PCR was employed to determine RNA expression. Biological behaviors of NSCLC cells were assessed by CCK-8, colony formation, EdU assay, flow cytometry, wound healing, and transwell assays. Glutamine catabolism was examined via the measurement of glutamine consumption, α-ketoglutarate levels, as well as ATP levels. Protein levels were detected by western blot assays. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were performed to reveal the mechanism responsible for circ-PITX1 regulating NSCLC cell malignancy. The murine xenograft model was established to investigate circ-PITX1's effect on tumor formation.

RESULTS

Circ-PITX1 was overexpressed in NSCLC tissue samples and cells. Its low expression repressed NSCLC cell proliferation and motility. Moreover, our data revealed its downregulation inhibited glutamine catabolism and tumor formation and promoted cell apoptosis. In addition, circ-PITX1 bound to miR-615-5p, and its inhibitory effect on tumor cellular behaviors could be reversed after decreasing miR-615-5p expression. The miRNA targeted E26 transformation specific-1 (ETS1), whose upregulation abolished miR-615-5p overexpression-induced effects in NSCLC cells. Furthermore, circ-PITX1 positively modulated ETS1 production through interaction with miR-615-5p.

CONCLUSION

Circ-PITX1 facilitated NSCLC progression via modulating miR-615-5p/ETS1 pathway.

摘要

背景

环状 RNA（circRNA）由反向剪接产生，在人类癌症中发挥重要作用。我们旨在评估垂体同源盒 1 环状 RNA（circ-PITX1）在非小细胞肺癌（NSCLC）中的生物学功能。

方法

采用 qRT-PCR 测定 RNA 表达。通过 CCK-8、集落形成、EdU 检测、流式细胞术、划痕愈合和 Transwell 检测评估 NSCLC 细胞的生物学行为。通过测定谷氨酰胺消耗、α-酮戊二酸水平以及 ATP 水平来检测谷氨酰胺分解代谢。通过 Western blot 检测蛋白水平。采用双荧光素酶报告基因和 RNA 免疫沉淀（RIP）检测来揭示 circ-PITX1 调节 NSCLC 细胞恶性的机制。建立小鼠异种移植模型来研究 circ-PITX1 对肿瘤形成的影响。

结果

circ-PITX1 在 NSCLC 组织样本和细胞中表达上调。其低表达抑制 NSCLC 细胞增殖和迁移。此外，我们的数据表明其下调抑制谷氨酰胺分解代谢和肿瘤形成并促进细胞凋亡。此外，circ-PITX1 与 miR-615-5p 结合，并且其对肿瘤细胞行为的抑制作用在降低 miR-615-5p 表达后可以逆转。该 miRNA 靶向 E26 转化特异性 1（ETS1），其上调消除了 miR-615-5p 过表达诱导的 NSCLC 细胞中的作用。此外，circ-PITX1 通过与 miR-615-5p 相互作用正向调节 ETS1 的产生。