视网膜母细胞瘤（RB）是儿童眼内肿瘤。积累的证据证实，microRNAs（miRNAs）在RB中具有关键功能。本研究旨在研究miR-452-5p在RB中的功能。通过定量实时聚合酶链式反应（PCR）测试RB中的miR-452-5p表达。通过细胞计数试剂盒-8、乙炔基-2'-脱氧尿苷实验、流式细胞仪、Western blot和Transwell评估RB中的miR-452-5p功能。使用生物信息学软件Starbase和双荧光素酶报告基因实验评估RB中的miR-452-5p机制。同时，通过在裸鼠中构建肿瘤异种移植物、免疫组织化学和Western blot实验检测miR-452-5p在RB中的体内功能。RB组织和细胞中miR-452-5p过表达，并且miR-452-5p表达与RB临床病理特征（包括最大肿瘤基底（mm）和分化）呈正相关。功能上，miR-452-5p敲降抑制RB细胞增殖、侵袭、上皮间质转化（EMT），并促进细胞凋亡。机制上，肿瘤细胞因子信号抑制蛋白（SOCS3）敲降恢复了miR-452-5p敲降对RB细胞的抑制作用。同时，体内研究进一步证实，miR-452-5p敲降减少了RB肿瘤的生长、EMT，并加速了体内细胞凋亡。此外，miR-452-5p敲降使SOCS3蛋白水平升高，并减少了体内磷酸化JAK2/JAK2、磷酸化STAT3/STAT3。miR-452-5p通过SOCS3/JAK2/STAT3促进RB细胞生长和侵袭。© 2023 Wiley Periodicals LLC.

Retinoblastoma (RB) is an intraocular tumor in children. Accumulated evidence confirms that microRNAs (miRNAs) exert critical functions in RB. This research aimed to investigate the miR-452-5p function in RB. MiR-452-5p expressions in RB were tested with quantitative real-time polymerase chain reaction (PCR). MiR-452-5p functions in RB were evaluated via Cell Counting Kit-8, 5-Ethynyl-2'-deoxyuridine assay, flow cytometry, Western blot, and Transwell. MiR-452-5p mechanism in RB was assessed using bioinformatics software Starbase and dual-luciferase reporter gene assay. Meanwhile, miR-452-5p function in RB in vivo was examined by constructing tumor xenografts in nude mice, immunohistochemistry, and Western blot assays. MiR-452-5p was overexpressed in RB tissues and cells, and miR-452-5p expression was positively correlated with RB clinicopathology including the Largest tumor base (mm) and Differentiation. Functionally, miR-452-5p knockdown restrained RB cell proliferation, invasion, epithelial-mesenchymal transition (EMT), and facilitated cell apoptosis. Mechanistically, suppressors of cytokine signaling (SOCS3) knockdown restored the inhibitory effects of miR-452-5p knockdown on RB cells. Meanwhile, in vivo studies further corroborated that miR-452-5p knockdown reduced RB tumor growth, EMT, and accelerated apoptosis in vivo. Also, miR-452-5p knockdown increased SOCS3 protein levels, and decreased phosphorylated Janus kinase 2/Janus kinase 2 (JAK2), phosphorylated signal transducer and activator of transcription 3/signal transducer and activator of transcription 3 (STAT3) in vivo. MiR-452-5p accelerated RB cell growth and invasion by SOCS3/JAK2/STAT3.© 2023 Wiley Periodicals LLC.