LncRNA XIST facilitates hypertrophy of ligamentum flavum by activating VEGFA-mediated autophagy through sponging miR-302b-3p

Abstract

Background: Increasing evidences have shown that long non-coding RNAs (lncRNAs) display crucial regulatory roles in the occurrence and development of numerous diseases. However, the function and underlying mechanisms of lncRNAs in hypertrophy of ligamentum flavum (HLF) have not been report. Methods: The integrated analysis of lncRNAs sequencing, bioinformatics analysis and real-time quantitative PCR were used to identify the key lncRNAs involved in HLF progression. Gain- and loss-function experiments were used to explore the functions of lncRNA X inactive specific transcript (XIST) in HLF. Mechanistically, bioinformatics binding site analysis, RNA pull-down, dual-luciferase reporter assay, and rescue experiments were utilized to investigate the mechanism by which XIST acts as a molecular sponge of miR-302b-3p to regulate VEGFA-mediated autophagy. Results: We identified that XIST was outstandingly upregulated in HLF tissues and cells. Moreover, the up-regulation of XIST strongly correlated with the thinness and fibrosis degree of LF in LSCS patients. Functionally, knockdown of XIST drastically inhibited proliferation, anti-apoptosis, fibrosis and autophagy of HLF cells in vitro and suppressed hypertrophy and fibrosis of LF tissues in vivo. Intestinally, we uncovered that overexpression of XIST significantly promoted proliferation, anti-apoptosis and fibrosis ability of HLF cells by activating autophagy. Mechanistic studies illustrated that XIST directly medullated the VEGFA-mediated autophagy through sponging miR-302b-3p, thereby enhancing the development and progression of HLF. Conclusion: Our findings highlighted that the XIST/miR-302b-3p/VEGFA-mediated autophagy axis is involved in development and progression of HLF. At the same time, this study will complement the blank of lncRNA expression profiles in HLF, which laid the foundation for further exploration of the relationship between lncRNAs and HLF in the future.