Basic Study
Copyright ©The Author(s) 2025. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Jul 18, 2025; 16(7): 107045
Published online Jul 18, 2025. doi: 10.5312/wjo.v16.i7.107045
miR-365 promotes HOXA9-mediated differentiation of mesenchymal stem cells to nucleus pulposus cells by interacting with HIF-1α
Zhong-Zheng Zhi, Tao Liu, Jian Kang, Fu-Chao Zhou, Xiao-Dong Liu, Zhi-Min He
Zhong-Zheng Zhi, Tao Liu, Jian Kang, Fu-Chao Zhou, Zhi-Min He, Department of Spine Surgery, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai 200434, China
Xiao-Dong Liu, Department of Orthopedics, Yangpu Hospital, School of Medicine, Tongji University, Shanghai 200090, China
Co-first authors: Zhong-Zheng Zhi and Tao Liu.
Co-corresponding authors: Xiao-Dong Liu and Zhi-Min He.
Author contributions: Zhi ZZ, Liu T, and Kang J participated in writing the manuscript; Zhi ZZ, Liu T, and Zhou FC performed project administration and data collection; Zhi ZZ, Liu T, and Kang J performed the data curation, formal analysis, and validation; Liu XD and He ZM helped examine and correct the manuscript; all authors have read and approved the final manuscript.
Supported by Academic Subject Boosting Plan in Shanghai Fourth People's Hospital Affiliated to Tongji University School of Medicine, No. SY-XKZT-2019-3002; Academic Project from the Health Commission of Hongkou District, Shanghai, No. 2202-25; and Clinical Key Specialty Construction Unit from The Health Commission of Hongkou District, Shanghai, No. HKLCZD2024B03.
Institutional animal care and use committee statement: Ethical approval was obtained from Animal Care and Use Committee of Wetry Biology (ID: WTPZ20230612001).
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Data sharing statement: Requests for data and materials should be addressed to Zhi-Min He.
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Zhi-Min He, Department of Spine Surgery, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, No. 1279 Sanmen Road, Hongkou District, Shanghai 200434, China. zzz0327@tongji.edu.cn
Received: March 14, 2025
Revised: April 14, 2025
Accepted: May 27, 2025
Published online: July 18, 2025
Processing time: 125 Days and 23.4 Hours
Abstract
BACKGROUND

Degenerative disc disease (DDD) is characterized by the loss of nucleus pulposus cells (NPCs). Inducing differentiation of bone marrow mesenchymal stem cells (MSCs) into NPCs has emerged as a novel therapeutic strategy for DDD. However, the efficiency of MSC differentiation and the underlying mechanisms remain to be fully elucidated.

AIM

To investigate the role and mechanism of miR-365 in promoting the differentiation of MSCs into NPCs for DDD treatment.

METHODS

In vitro, the effects of miR-365 on MSC proliferation, apoptosis, and differentiation were assessed by cell counting kit-8 assay, flow cytometry, and quantitative real-time polymerase chain reaction (qRT-PCR). In vivo, the expression levels of miR-365, HIF-1α, Sox9, Kdm6a, and HOXA9 in the spinal cord of rats with spinal cord injury were determined by qRT-PCR and Western blot.

RESULTS

In vitro, miR-365 significantly promoted MSC proliferation and inhibited MSC apoptosis. The expression levels of glycosaminoglycans, proteoglycan, and type 2 collagen were significantly increased with miR-365 ectopic expression. In vivo, the expression levels of miR-365, HIF-1α, Sox9, and Kdm6a were significantly increased, whereas HOXA9 was remarkably decreased. Mechanically, miR-365 inhibited HOXA9 expression by directly binding to its 3’ untranslated region. HOXA9 could inhibit HIF-1α expression by binding to the Hif-1α promoter, thereby affecting the expression levels of Sox9 and Kdm6a. Moreover, HOXA9 knockdown significantly reversed the differentiation of MSCs into NPCs induced by miR-365.

CONCLUSION

miR-365 promotes HOXA9-mediated differentiation of MSCs into NPCs by interacting with HIF-1α and may serve as a potential target for DDD treatment.

Keywords: Degenerative disc disease; Nucleus pulposus cell; miR-365; HOXA9; HIF-1α

Core Tip: This study investigates the role of miR-365 in promoting the differentiation of bone marrow mesenchymal stem cells (MSCs) into nucleus pulposus cells (NPCs) for degenerative disc disease (DDD) treatment. We reveal that miR-365 enhances MSC proliferation and inhibits apoptosis, while promoting NPC-related marker expression. Mechanistically, miR-365 targets HOXA9, which in turn regulates HIF-1α, Sox9, and Kdm6a. This finding highlights miR-365 as a potential therapeutic target for DDD, offering a novel strategy to address the loss of NPCs.