Lv Yaming, Wang Lan, Zhang Yunhui, Wei Dong, Hu Yajie
Department of Respiratory Medicine, The Affiliated Hospital of Kunming University of Science and Technology, Kunming, China.
Department of Respiratory Medicine, The First People's Hospital of Yunnan Province, Kunming, China.
Front Oncol. 2025 Feb 17;15:1441384. doi: 10.3389/fonc.2025.1441384. eCollection 2025.
Lung cancer has a higher incidence and mortality rate than other cancers, especially non-small cell lung cancer (NSCLC), accounting for 85% of the cases. The role of the circDENND4C/miR-200b/matrix metalloproteinase-9 (MMP-9) regulatory axis in NSCLC remains largely unknown.
NSCLC cell lines were used to examine the expression of circDENND4C, miR-200b, and MMP-9 via qRT-PCR or Western blot. The target relationship of circDENND4C, miR-200b, and MMP-9 was examined by RNA fluorescence hybridization (RNA-FISH), immunofluorescence (IF), dual-luciferase reporter system, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot. Then, a cell count kit-8 (CCK-8) experiment, flow cytometry, and migration/invasion assays were performed to assess the biological function of circDENND4C, miR-200b, and MMP-9 by transfecting with their overexpression or knockout plasmids in A549 cells. Finally, the proteins related to cell adhesion and tight junction were further tested by Western blot and IF.
circDENND4C and MMP-9 were found to be highly expressed in NSCLC cell lines, while miR-200b was lowly expressed in NSCLC cell lines. Moreover, circDENND4C could sponge miR-200b to target MMP-9. Subsequently, it was observed that knockdown of circDENND4C and MMP-9 or the upregulation of miR-200b repressed cell proliferation and cell cycle progression, increased cell apoptosis, and hindered cell migration and invasion. Finally, it was also found that the circDENND4C/miR-200b/MMP-9 regulatory axis might be involved with cell adhesion and tight junction to influence tumor metastasis.
Altogether, our study reveals a novel regulatory loop in which the circDENND4C/miR-200b/MMP-9 axis may modulate NSCLC progression, indicating potential biomarkers for the diagnosis or treatment of NSCLC.
肺癌的发病率和死亡率高于其他癌症，尤其是非小细胞肺癌（NSCLC），占病例的85%。环状DENND4C/微小RNA-200b/基质金属蛋白酶-9（MMP-9）调控轴在非小细胞肺癌中的作用在很大程度上仍不清楚。
使用非小细胞肺癌细胞系通过定量逆转录聚合酶链反应（qRT-PCR）或蛋白质免疫印迹法检测环状DENND4C、微小RNA-200b和MMP-9的表达。通过RNA荧光原位杂交（RNA-FISH）、免疫荧光（IF）、双荧光素酶报告系统、定量实时聚合酶链反应（qRT-PCR）和蛋白质免疫印迹法检测环状DENND4C、微小RNA-200b和MMP-9之间的靶向关系。然后，通过在A549细胞中过表达或敲除它们的质粒进行细胞计数试剂盒-8（CCK-8）实验、流式细胞术和迁移/侵袭实验，以评估环状DENND4C、微小RNA-200b和MMP-9的生物学功能。最后，通过蛋白质免疫印迹法和免疫荧光进一步检测与细胞黏附和紧密连接相关的蛋白质。
发现环状DENND4C和MMP-9在非小细胞肺癌细胞系中高表达，而微小RNA-200b在非小细胞肺癌细胞系中低表达。此外，环状DENND4C可以吸附微小RNA-200b以靶向MMP-9。随后，观察到敲低环状DENND4C和MMP-9或上调微小RNA-200b可抑制细胞增殖和细胞周期进程，增加细胞凋亡，并阻碍细胞迁移和侵袭。最后，还发现环状DENND4C/微小RNA-200b/MMP-9调控轴可能参与细胞黏附和紧密连接以影响肿瘤转移。
总之，我们的研究揭示了一个新的调控环路，其中环状DENND4C/微小RNA-200b/MMP-9轴可能调节非小细胞肺癌的进展，为非小细胞肺癌的诊断或治疗指明了潜在的生物标志物。
