ABSTRACT

Circular RNAs (circRNAs) possess important regulatory effects on multiple myeloma (MM) progression. Here, we aimed at exploring the function of circ_0007841 in MM and the underlying molecular mechanism. Expression of circ_0007841, microRNA (miR)-129-5p and Jagged1 (JAG1) was determined via qRT-PCR or western blot assay. Methyl thiazolyl tetrazolium (MTT) assay was applied to examine cell viability and IC50 value of MM cells to bortezomib (BTZ). Colony formation assay was performed to analyze cell proliferation. Moreover, cell apoptosis was assessed by flow cytometry and western blot analysis. Cell metastasis was evaluated by wound healing assay and Transwell assay. Function of circ_0007841 in vivo was determined by xenograft tumor assay. Target relationship between miR-129-5p and circ_0007841 or JAG1 was confirmed via dual-luciferase reporter, RNA immunoprecipitation (RIP) and pull-down assays. The up-regulation of circ_0007841 and JAG1, and the down-regulation of miR-129-5p were detected in MM bone marrow aspirates and cells. Circ_0007841 knockdown significantly repressed cell proliferation, chemoresistance, and metastasis, while contributed to apoptosis of MM cells in vitro, and reduced tumor growth in vivo. Circ_0007841 targeted miR-129-5p, and miR-129-5p inhibition reversed impact of silencing of circ_0007841 on MM cells. JAG1 was a mRNA target of miR-129-5p, whose overexpression could undermine the miR-129-5p-mediated effects on MM cells. Circ_0007841 positively regulated JAG1 expression via absorbing miR-129-5p. Circ_0007841 knockdown inhibited MM cell proliferation, metastasis and chemoresistance through modulating miR-129-5p/JAG1 axis, suggesting that circ_0007841 might serve as a potential therapeutic target of MM.

摘要

环状RNA（circRNA）对多发性骨髓瘤（MM）的进展具有重要的调节作用。在这里，我们旨在探索 circ_0007841 在 MM 中的功能和潜在的分子机制。circ_0007841、microRNA (miR)-129-5p 和 Jagged1 (JAG1) 的表达通过 qRT-PCR 或蛋白质印迹分析确定。甲基噻唑基四唑鎓（MTT）测定用于检查MM细胞对硼替佐米（BTZ）的细胞活力和IC50值。进行集落形成测定以分析细胞增殖。此外，通过流式细胞术和蛋白质印迹分析评估细胞凋亡。通过伤口愈合试验和Transwell试验评估细胞转移。circ_0007841在体内的作用通过异种移植肿瘤测定确定。miR-129-5p 和 circ_0007841 或 JAG1 之间的靶标关系通过双荧光素酶报告基因、RNA 免疫沉淀 (RIP) 和下拉分析得到证实。在MM骨髓抽吸物和细胞中检测到circ_0007841和JAG1的上调以及miR-129-5p的下调。Circ_0007841敲低显着抑制细胞增殖、化学抗性和转移，同时在体外促进MM细胞凋亡，并减少体内肿瘤生长. Circ_0007841 靶向 miR-129-5p，miR-129-5p 抑制逆转了 circ_0007841 沉默对 MM 细胞的影响。JAG1 是 miR-129-5p 的 mRNA 靶标，其过表达会破坏 miR-129-5p 介导的对 MM 细胞的影响。Circ_0007841 通过吸收 miR-129-5p 正调控 JAG1 的表达。circ_0007841 敲低通过调节 miR-129-5p/JAG1 轴抑制 MM 细胞增殖、转移和化学抗性，表明 circ_0007841 可能作为 MM 的潜在治疗靶点。