Circular RNA Expression Profile in Patients with Lumbar Spinal Stenosis Associated with Hypertrophied Ligamentum Flavum.

STUDY DESIGN: Sequencing and experimental analysis of the expression profile of circular RNAs (circRNAs) in hypertrophic ligamentum flavum (LFH). OBJECTIVES: The aim of this study was to identify differentially expressed circRNAs between LFH and nonhypertrophic ligamentum flavum tissues from lumbar spinal stenosis (LSS) patients. SUMMARY OF BACKGROUND DATA: Hypertrophy of the ligamentum flavum (LF) can cause LSS. circRNAs are important in various diseases. However, no circRNA expression patterns related to LF hypertrophy have been reported. METHODS: A total of 33 patients with LSS participated in this study. LF tissue samples were obtained when patients underwent decompressive laminectomy during surgery. The expression profile of circRNAs was analyzed by transcriptome high-throughput sequencing and validated with quantitative real-time polymerase chain reaction (PCR). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed for the differentially expressed circRNA-associated genes and related pathways. The connections between circRNAs and microRNAs were explored using Cytoscape. The role of hsa_circ_0052318 on LF cell fibrosis was assessed by analyzing the expression of collagen I and collagen III. RESULTS: The results showed that 2439 circRNAs of 4025 were differentially expressed between the LFH and nonhypertrophic ligamentum flavum tissues, including 1276 upregulated and 1163 downregulated circRNAs. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that these differentially expressed circRNAs functioned in biological processes, cellular components, and molecular functions. Autophagy and mammalian target of rapamycin were the top two signaling pathways affected by these circRNAs. Five circRNAs (hsa_circ_0021604, hsa_circ_0025489, hsa_circ_0002599, hsa_circ_0052318, and hsa_circ_0003609) were confirmed by quantitative real-time PCR. The network indicated a strong relationship between circRNAs and miRNAs. Furthermore, hsa_circ_0052318 overexpression decreased mRNA and protein expression of collagen I and III in LF cells from LFH tissues. CONCLUSION: This study identified circRNA expression profiles characteristic of hypertrophied LF in LSS patients, and demonstrated that hsa_circ_0052318 may play an important role in the pathogenesis of LF hypertrophy.Level of Evidence: N/A.

Paclitaxel Induce Apoptosis of Giant Cells Tumor of Bone via TP53INP1 Signaling.

OBJECTIVE: To evaluate the antitumor capability and to investigate the underlying molecular mechanism of paclitaxel. METHODS: First, cck-8 and apoptosis assays were used to determine survival and apoptotic effects of HS 737.T cells under treatment of paclitaxel. Next, RNA-seq and bioinformatics were used to determine the differentially expressed genes and to analyze the pathway involved. Quantitative real-time polymerase chain reaction was used to verify the accuracy of some differentially expressed genes (DEG). ClueGO was used to decode and visualize functionally grouped GO terms of differentially expressed genes, and to map the DEG protein-protein interactions (PPI) network. Western blotting was used to check the expression of target genes, the cleavage of Caspase-3 and PARP1, and the phosphorylation level of p53. Finally, transcriptomics, bioinformatics, and RNAi were used to estimate the antitumor capability and to identify the underlying mechanisms of paclitaxel in GCTB. RESULTS: Our data revealed that paclitaxel had significant time-dependent effects on the viability and induced apoptosis of HS 737.T cells. RNA-seq and bioinformatics analysis showed that apoptosis, death receptor signaling pathway, TNF signaling pathway, and TP53 regulated transcription of cell death genes pathway were closely associated with paclitaxel in the treatment of GCTB. Western bolt results revealed that paclitaxel induced cleavage of Caspase-3 and PARP1, and increased the phosphorylation level of p53 in HS 737.T cells. RNAi results showed that the expression level of TP53INP1 was significantly decreased in HS737.T cells (the decrease was more than 70%). In addition, we found that the inhibitory ratios of paclitaxel on HS737.T cells deficient in TP53INP1 were less than in HS737.T cells with empty vector (19.88 and 40.60%, respectively). Hence, our data revealed that TP53INP1 regulated paclitaxel-driven apoptosis in HS737.T cells. CONCLUSION: Paclitaxel can significantly repress cell proliferation and induce apoptosis of HS 737.T cells through activating Caspase-3, PARP1, p53, and TP53INP1. Paclitaxel may be an effective drug in the management of GCTB.

Two-phase electrospinning to incorporate growth factors loaded chitosan nanoparticles into electrospun fibrous scaffolds for bioactivity retention and cartilage regeneration.

Growth factor is an essential ingredient to regulate mesenchymal stem cells (MSCs) chondrogenic differentiation in cartilage tissue engineering. However, non-osteochondral specification, short plasma half time and bioactivity loss restrict growth factor's application. Thus, novel chondrogenic growth factors, specifically target osteochondral lineage cells, that can be sustained release and bioactivity protected to exert functions continually and effectively have attracted increasing researchers' interest. To achieve these goals, chitosan nanoparticles and electrospun fiber scaffolds were used as dual release system to sustain release Nel-like molecule-1 (Nell-1) growth factor and protect bioactivity, then the effect and mechanism of Nell-1 on inducing human bone MSCs (hBMSCs) differentiate toward chondrocytes were investigated. For release and bioactivity protection study, preloading Nell-1 into chitosan nanoparticles significantly extended the release time, increased the released Nell-1's bioactivity than directly incorporating Nell-1 into the scaffolds. Furthermore, Nell-1 specifically promotes hBMSCs in vitro chondrogenic differentiation by increasing expression of chondrogenic related genes and proteins. These findings suggest the potential utility of Nell-1 incorporated dual release scaffold for cartilage tissue engineering.

Sex-determining region Y-box protein 3 induces epithelial-mesenchymal transition in osteosarcoma cells via transcriptional activation of Snail1.

BACKGROUND: The transcription factor sex-determining region Y-box protein 3 (SOX3) plays important roles in various types of cancer. However, its expression and function have not yet been elucidated in osteosarcoma (OS). METHODS: The expression levels of SOX3 in OS tissues and OS cell lines were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis. The effects of SOX3 expression on OS cell biological traits were investigated by overexpressing and downregulating SOX3 protein. The expression of epithelial-mesenchymal transition (EMT) markers and transcription factors associated with EMT (EMT-TFs), were detected simultaneously. The mechanism underlying SOX3-mediated Snail1 expression was further investigated. RESULTS: SOX3 was upregulated in human OS tissues. SOX3 overexpression promoted the EMT, migration and invasion in OS cells. The downregulation of SOX3 resulted in opposing effects. Furthermore, SOX3 upregulation enhanced the expression of the transcriptional repressor Snail1 by binding to its promoter region. Additionally, a positive correlation among the expression of SOX3, Snail1, and E-cadherin was demonstrated in human OS tissues. CONCLUSIONS: SOX3 promotes migration, invasiveness, and EMT in OS cells via transcriptional activation of Snail1 expression, suggesting that SOX3 is a novel regulator of EMT in OS and may serve as a therapeutic target for the treatment of OS metastasis.

Platelet-Rich Plasma-Loaded Poly(d,l-lactide)-Poly(ethylene glycol)-Poly(d,l-lactide) Hydrogel Dressing Promotes Full-Thickness Skin Wound Healing in a Rodent Model.

Traditional therapeutic methods for skin wounds have many disadvantages, and new wound dressings that can facilitate the healing process are thus urgently needed. Platelet-rich plasma (PRP) contains multiple growth factors (GFs) and shows a significant capacity to heal soft tissue wounds. However, these GFs have a short half-life and deactivate rapidly; we therefore need a sustained delivery system to overcome this shortcoming. In this study, poly(d,l-lactide)-poly(ethylene glycol)-poly(d,l-lactide) (PDLLA-PEG-PDLLA: PLEL) hydrogel was successfully created as delivery vehicle for PRP GFs and was evaluated systematically. PLEL hydrogel was injectable at room temperature and exhibited a smart thermosensitive in situ gel-formation behavior at body temperature. In vitro cell culture showed PRP-loaded PLEL hydrogel (PRP/PLEL) had little cytotoxicity, and promoted EaHy926 proliferation, migration and tube formation; the factor release assay additionally indicated that PLEL realized the controlled release of PRP GFs for as long as 14 days. When employed to treat rodents' full-thickness skin defects, PRP/PLEL showed a significantly better ability to raise the number of both newly formed and mature blood vessels compared to the control, PLEL and PRP groups. Furthermore, the PRP/PLEL-treated group displayed faster wound closure, better reepithelialization and collagen formation. Taken together, PRP/PLEL provides a promising strategy for promoting angiogenesis and skin wound healing, which extends the potential of this dressing for clinical application.