State Key Laboratory of Pharmaceutical Biotechnology, Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China.
State Key Laboratory of Pharmaceutical Biotechnology, Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China; Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Nanjing, China.
Biomed J. 2024 Jun;47(3):100651. doi: 10.1016/j.bj.2023.100651. Epub 2023 Aug 9.
Dysregulation of long non-coding RNAs (lncRNAs) is an important component of tumorigenesis. Aberrant expression of lncRNA taurine upregulated gene 1 (lncTUG1) has been reported in various tumors; however, its precise role and key targets critically involved in osteosarcoma (OS) progression remain unclear.
The expression profiles of lncRNAs and their regulated miRNAs related to OS progression were assessed by bioinformatics analysis and confirmed by qRT-PCR of OS cells. The miRNA targets were identified by transcriptome sequencing and verified by luciferase reporter and RNA pull-down assays. Several in vivo and in vitro approaches, including CCK8 assay, western blot, qRT-PCR, lentiviral transduction and OS cell xenograft mouse model were established to validate the effects of lncTUG1 regulation of miRNA and the downstream target genes on OS cell growth, apoptosis and progression.
We found that lncTUG1 and miR-26a-5p were inversely up or down-regulated in OS cells, and siRNA-mediated lncTUG1 knockdown reversed the miR-26a-5p down-regulation and suppressed proliferation and enhanced apoptosis of OS cells. Further, we identified that an oncoprotein ZBTB7C was also upregulated in OS cells that were subjected to lncTUG1/miR-26a-5p regulation. More importantly, ZBTB7C knockdown reduced the ZBTB7C upregulation and ZBTB7C overexpression diminished the anti-OS effects of lncTUG1 knockdown in the OS xenograft model.
Our data suggest that lncTUG1 acts as a miR-26a-5p sponge and promotes OS progression via up-regulating ZBTB7C, and targeting lncTUG1 might be an effective strategy to treat OS.
长链非编码 RNA（lncRNA）的失调是肿瘤发生的一个重要组成部分。在各种肿瘤中都报道了 lncRNA 牛磺酸上调基因 1（lncTUG1）的异常表达；然而，其在骨肉瘤（OS）进展中的确切作用和关键靶点仍不清楚。
通过生物信息学分析评估了与 OS 进展相关的 lncRNA 和其调节 miRNA 的表达谱，并通过 OS 细胞的 qRT-PCR 进行了验证。通过转录组测序鉴定了 miRNA 的靶标，并通过荧光素酶报告和 RNA 下拉测定进行了验证。建立了几种体内和体外方法，包括 CCK8 测定、western blot、qRT-PCR、慢病毒转导和 OS 细胞异种移植小鼠模型，以验证 lncTUG1 对 miRNA 和下游靶基因的调节对 OS 细胞生长、凋亡和进展的影响。
我们发现 lncTUG1 和 miR-26a-5p 在 OS 细胞中呈反向上调或下调，siRNA 介导的 lncTUG1 敲低逆转了 miR-26a-5p 的下调，并抑制了 OS 细胞的增殖和促进了凋亡。此外，我们还发现 ZBTB7C 癌蛋白在受 lncTUG1/miR-26a-5p 调节的 OS 细胞中也上调。更重要的是，ZBTB7C 敲低减少了 ZBTB7C 的上调，而过表达 ZBTB7C 则减弱了 lncTUG1 敲低在 OS 异种移植模型中的抗 OS 作用。
我们的数据表明，lncTUG1 作为 miR-26a-5p 的海绵体，通过上调 ZBTB7C 促进 OS 进展，靶向 lncTUG1 可能是治疗 OS 的有效策略。
