背景:胃癌(GC)是世界范围内常见的癌症;然而,其分子机制和致病机制尚不清楚。microRNAs(miRNAs),靶向GC中的关键基因,与肿瘤的促进或抑制有关。因此,识别新的miRNA机制可以改善GC患者的新诊断和治疗策略。
方法:探讨miR-135b-5p在GC中的生物学功能,生物信息学分析和体外功能测定,包括菌落形成,伤口愈合,Transwell,和EdU化验,用于评估增殖,侵入性,和GC细胞的迁移能力。使用RNA-seq和在线数据库预测靶基因。双荧光素酶报告基因测定,荧光原位杂交和免疫印迹用于确认miR-135b-5p和CLIP4之间的调控关系。使用临床样品以及体外和体内测定来评估CLIP4在肿瘤进展中的作用。使用挽救试验阐明了CLIP4在GC中的肿瘤抑制机制。
结果:我们的研究确定miR-135b-5p是GC组织中超表达的三大miRNA之一,RT-qPCR证实其上调。功能分析显示上调的miR-135b-5p促进GC细胞的恶性表型。机制研究表明miR-135b-5p通过靶向CLIP4作为癌症启动子。此外,我们的研究提示CLIP4通过抑制JAK2/STAT3信号通路发挥肿瘤抑制功能.
结论:本研究揭示了miR-135b-5p通过靶向CLIP4发挥其肿瘤促进功能的新机制。还阐明了CLIP4通过灭活JAK2/STAT3途径的肿瘤抑制功能。miR-135b-5p对CLIP4的调控机制为GC患者提供了一种有前景的新型治疗策略。
BACKGROUND: Gastric cancer (GC) is a common cancer worldwide; however, its molecular and pathogenic mechanisms remain unclear. MicroRNAs (miRNAs), which target key genes in GC, are associated with tumor promotion or suppression. Therefore, identifying new miRNA mechanisms could improve the novel diagnostic and therapeutic strategies for patients with GC.
METHODS: To explore the biological functions of miR-135b-5p in GC, bioinformatic analysis and in vitro functional assays, including colony formation, wound healing, Transwell, and EdU assays, were used to assess the proliferative, invasive, and migratory capacities of GC cells. Target genes were predicted using RNA-seq and online databases. Dual-luciferase reporter assay, fluorescence in situ hybridization and western blotting were used to confirm the regulatory relationship between miR-135b-5p and CLIP4. The role of CLIP4 in tumor progression was assessed using clinical samples and both in vitro and in vivo assays. The tumor-suppressive mechanism of CLIP4 in GC was elucidated using rescue assays.
RESULTS: Our study identified that miR-135b-5p as one of the top three over-expressed miRNAs in GC tissues, with RT-qPCR confirming its upregulation. Functional analysis showed that upregulated miR-135b-5p promoted malignant phenotypes in GC cells. Mechanistic research indicated that miR-135b-5p acts as a cancer promoter by targeting CLIP4. Moreover, our study suggested that CLIP4 exerts its tumor-suppressive function by inhibiting the JAK2/STAT3 signaling pathway.
CONCLUSIONS: This study reveals a novel mechanism by which miR-135b-5p exerts its tumor-promoting functions by targeting CLIP4. The tumor-suppressive function of CLIP4 by inactivating the JAK2/STAT3 pathway is also elucidated. Regulatory mechanism of CLIP4 by miR-135b-5p provides a promising novel therapeutic strategy for GC patients.