ABSTRACT

Background

Multiple functions of miR-199b-5p in diseases have been demonstrated by existing studies. However, never has the correlation between miR-199b-5p and multiple myeloma (MM) been established.

Methods

qRT-PCR analyzed RNA expression and western blot measured protein expression. Cell proliferation ability was tested via colony formation and EdU assays, and apoptosis was determined via TUNEL, flow cytometry and detection of apoptosis-related proteins. Position of LRRC75A antisense RNA 1 (LRRC75A-AS1) was recognized by FISH assay. RIP, RNA pull-down and luciferase reporter experiments explored the molecular interplay.

Results

GEO (Gene Expression Omnibus) data revealed miR-199b-5p upregulation in MM specimens, and qRT-PCR data verified miR-199b-5p upregulation in MM cells. Inhibiting miR-199b-5p markedly impeded MM cell proliferation and stimulated apoptosis. Moreover, we demonstrated the mechanism that miR-199b-5p was decoyed by LRRC75A-AS1 and miR-199b-5p targeted programmed cell death 4 (PDCD4) to repress its expression. Further, LRRC75A-AS1 was verified to repress proliferation and prompt apoptosis in a PDCD4-dependent way in MM cells.

Conclusion

Our data displayed that miR-199b-5p was sequestered by LRRC75A-AS1 so that PDCD4 was released to repress MM, implying the targeting miR-199b-5p as a novel thought for improving MM therapy.

中文翻译：

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LRRC75A-AS1 靶向 miR-199b-5p/PDCD4 轴以抑制多发性骨髓瘤

摘要

背景

现有研究已经证明了 miR-199b-5p 在疾病中的多种功能。然而，从未建立过 miR-199b-5p 与多发性骨髓瘤 (MM) 之间的相关性。

方法

qRT-PCR 分析了 RNA 表达，蛋白质印迹测量了蛋白质表达。细胞增殖能力通过集落形成和EdU测定进行测试，凋亡通过TUNEL、流式细胞术和凋亡相关蛋白的检测来确定。LRRC75A 反义 RNA 1 (LRRC75A-AS1) 的位置由 FISH 测定识别。RIP、RNA 下拉和荧光素酶报告基因实验探索了分子间的相互作用。

结果

GEO（基因表达综合）数据显示 MM 标本中的 miR-199b-5p 上调，qRT-PCR 数据证实了 MM 细胞中的 miR-199b-5p 上调。抑制 miR-199b-5p 显着阻碍 MM 细胞增殖并刺激细胞凋亡。此外，我们证明了 miR-199b-5p 被 LRRC75A-AS1 和 miR-199b-5p 靶向程序性细胞死亡 4（PDCD4）诱骗以抑制其表达的机制。此外，证实 LRRC75A-AS1 在 MM 细胞中以 PDCD4 依赖性方式抑制增殖并促进细胞凋亡。

结论

我们的数据显示 miR-199b-5p 被 LRRC75A-AS1 隔离，从而释放 PDCD4 以抑制 MM，这意味着靶向 miR-199b-5p 是改善 MM 治疗的新思路。