Emerging roles of non-coding RNAs in scoliosis

Investigating the Differential Circulating microRNA Expression in Adolescent Females with Severe Idiopathic Scoliosis: A Proof-of-Concept Observational Clinical Study

Adolescent Idiopathic Scoliosis (AIS) is the most common form of three-dimensional spinal disorder in adolescents between the ages of 10 and 18 years of age, most commonly diagnosed in young women when severe disease occurs. Patients with AIS are characterized by abnormal skeletal growth and reduced bone mineral density. The etiology of AIS is thought to be multifactorial, involving both environmental and genetic factors, but to date, it is still unknown. Therefore, it is crucial to further investigate the molecular pathogenesis of AIS and to identify biomarkers useful for predicting curve progression. In this perspective, the relative abundance of a panel of microRNAs (miRNAs) was analyzed in the plasma of 20 AIS patients and 10 healthy controls (HC). The data revealed a significant group of circulating miRNAs dysregulated in AIS patients compared to HC. Further bioinformatic analyses evidenced a more restricted expression of some miRNAs exclusively in severe AIS females. These include some members of the miR-30 family, which are considered promising regulators for treating bone diseases. We demonstrated circulating extracellular vesicles (EVs) from severe AIS females contained miR-30 family members and decreased the osteogenic differentiation of mesenchymal stem cells. Proteomic analysis of EVs highlighted the expression of proteins associated with orthopedic disease. This study provides preliminary evidence of a miRNAs signature potentially associated with severe female AIS and suggests the corresponding vesicular component may affect cellular mechanisms crucial in AIS, opening the scenario for in-depth studies on prognostic differences related to gender and grade.

Research progress on the regulation of bone marrow stem cells by noncoding RNAs in adolescent idiopathic scoliosis

Adolescent idiopathic scoliosis (AIS) is a common spinal deformity in young women, but its pathogenesis remains unclear. The primary pathogenic factors contributing to its development include genetics, abnormal bone metabolism, and endocrine factors. Bone marrow stem cells (BMSCs) play a crucial role in the pathogenesis of AIS by regulating its occurrence and progression. Noncoding RNAs (ncRNAs) are also involved in the pathogenesis of AIS, and their role in regulating BMSCs in patients with AIS requires further evaluation. In this review, we discuss the relevant literature regarding the osteogenic, chondrogenic, and lipogenic differentiation of BMSCs. The corresponding mechanisms of ncRNA-mediated BMSC regulation in patients with AIS, recent advancements in AIS and ncRNA research, and the importance of ncRNA translation profiling and multiomics are highlighted.

Down-regulation of long noncoding RNA HULC inhibits the inflammatory response in ankylosing spondylitis by reducing miR-556-5p-mediated YAP1 expression

OBJECTIVE

Ankylosing spondylitis (AS) is a progressive systemic disease characterized by a chronic inflammatory response in the sacroiliac joints and spine. Long noncoding RNAs suggest significant actions in the progression of AS. Therefore, a specific lncRNA, highly upregulated in liver cancer (HULC), was studied here regarding its functions and related mechanisms in AS.

METHODS

Measurements of miR-556-5p, HULC, and YAP1 expression were performed on AS cartilage tissues and chondrocytes. The interaction between miR-556-5p and HULC or YAP1 was verified. CCK-8, flow cytometry and enzyme-linked immunosorbent assay were used to evaluate the effects of HULC, miR-556-5p, and YAP1 on the proliferation, apoptosis, and inflammatory response of AS chondrocytes. Furthermore, the action of HULC/miR-556-5p/YAP1 was experimentally observed in AS mice.

RESULTS

HULC and YAP1 levels were augmented, while miR-556-5p levels were suppressed in AS cartilage tissues and chondrocytes. Downregulating HULC or upregulating miR-556-5p stimulated chondrocyte proliferation and inhibited apoptosis and inflammation in AS. miR-556-5p was a downstream factor of HULC, and YAP1 was a potential target of miR-556-5p. The improvement effect of downregulated HULC on AS chondrocytes was saved when YAP1 expression was forced. In addition, silence of HULC improved the pathological injury of spinal cartilage in AS mice by enhancing miR-556-5p-related regulation of YAP1.

CONCLUSION

HULC inhibition relieves the inflammatory response in AS by reducing miR-556-5p-mediated YAP1 expression.

The Potential Role of Dysregulated miRNAs in Adolescent Idiopathic Scoliosis and 22q11.2 Deletion Syndrome

Background: Adolescent idiopathic scoliosis (AIS), affecting 2-4% of adolescents, is a multifactorial spinal disease. Interactions between genetic and environmental factors can influence disease onset through epigenetic mechanisms, including DNA methylation, histone modifications and miRNA expression. Recent evidence reported that, among all clinical features in individuals with 22q11.2 deletion syndrome (DS), scoliosis can occur with a higher incidence than in the general population. Methods: A PubMed and Ovid Medline search was performed for idiopathic scoliosis in the setting of 22q11.2DS and miRNA according to PRISMA guidelines. Results: Four papers, accounting for 2841 individuals, reported clinical data about scoliosis in individuals with 22q11.2DS, showing that approximately 35.1% of the individuals with 22q11.2DS developed scoliosis. Conclusions: 22q11.2DS could be used as a model for the study of AIS. The DGCR8 gene seems to be essential for microRNA biogenesis, which is why we propose that a possible common pathological mechanism between scoliosis and 22q11.2DS could be the dysregulation of microRNA expression. In the current study, we identified two miRNAs that were altered in both 22q11.2DS and AIS, miR-93 and miR-1306, thus, corroborating the hypothesis that the two diseases share common molecular alterations.

Circ_0005918 Sponges miR-622 to Aggravate Intervertebral Disc Degeneration

Intervertebral discdegeneration (IDD) is the most common cause of lower back pain, but the exact molecular mechanism of IDD is still unknown. Recently, studies have shown that circular RNAs (circRNAs) regulate diverse biological procedures such as cell metastasis, growth, metabolism, migration, apoptosis, and invasion. We demonstrated that IL-1β and TNF-α induced circ_0005918 expression in the NP cell, and circ_0005918 was overexpressed in the IDD group compared with the control group. Moreover, the upregulated expression of circ_0005918 was associated with disc degeneration degree. The elevated expression of circ_0005918 promoted cell growth and ECM degradation, and it induced secretion of inflammatory cytokines including IL-1β, IL-6, and TNF-α. Moreover, we found that circ_0005918 sponged miR-622 in the NP cell. In addition, the exposure to IL-1β and TNF-α suppressed the expression of miR-622, which was downregulated in the IDD group compared with the control group. Furthermore, the downregulated expression of miR-622 was associated with disc degeneration degree. The expression level of miR-622 was negatively associated with circ_0005918 expression in the IDD group. In conclusion, circ_0005918 regulated cell growth, ECM degradation, and secretion of inflammatory cytokines by regulating miR-622 expression. These data suggested that circ_0005918 played important roles in the development of IDD via sponging miR-622.

LncRNA FER1L4 promotes differentiation and inhibits proliferation of NSCs via miR-874-3p/Ascl2

Neural stem cells (NSCs) may offer beneficeial and promising adjuncts for treatment of neurological diseases such as Alzheimer's disease (AD), Parkinson's disease (PD) and spinal cord injuries. Previous studies showed that LncRNA FER1L4 plays crucial roles in many biological procedures such as invasion, metabolism, apoptosis, and stem cell differentiation. However, the role of FER1L4 in differentiation and growth of NSCs remains unknown. In the present research, we noted that FER1L4 is upregulated in NSCs induced with TNFα. Ectopic expression of FER1L4 suppresses NSCs proliferation and induces NSCs differentiated into neurons and astrocytes. Using Starbase online software, we identified that FER1L4 is one potential target gene of miR-874-3p. Ectopic expression of FER1L4 decreases miR-874-3p expression in NSCs. We identified Ascl2 is one target gene for miR-874-3p. Overexpression of FER1L4 enhances Ascl2 expression in NSCs. Furthermore, we proved that FER1L4 modulates the proliferation and differentiation of NSCs via regulating Ascl2.

Emerging Roles of Long Non-Coding RNAs in Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a chronic systemic autoimmune disease characterized by inflammation, bone erosion, spur formation of the spine and the sacroiliac joints. However, the etiology and molecular pathogenesis of AS remain largely unclear. Recently, a growing number of studies showed that long non-coding RNAs (lncRNAs) played critical roles in the development and progression of autoimmune and orthopedic conditions, including AS. Studies demonstrated that a myriad of lncRNAs (e.g. H19, MEG3, LOC645166) pertinent to regulation of inflammatory signals were deregulated in AS. A number of lncRNAs might also serve as new biomarkers for the diagnosis and predicting the outcomes of AS. In this review, we summarize lncRNA profiling studies on AS and the functional roles and mechanism of key lncRNAs relevant to AS pathogenesis. We also discuss their potential values as biomarkers and druggable targets for this potentially disabling condition.

Hsa_circ_0134111 promotes intervertebral disc degeneration via sponging miR-578

Intervertebral disc degeneration (IDD) is a chronic degenerative and age-dependent process characterized by aberrant apoptosis, proliferation, synthesis, and catabolism of the extracellular matrix of the nucleus pulposus (NP) cells. Recently, studies showed that circular RNAs play important roles in the development of many diseases. However, the role of circRNAs in IDD development remains unknown. We showed that circ_0134111 level was overexpressed in IDD tissue samples as compar-ed to control tissues. The upregulation of circ_0134111 was more drastic in the moderate and severe IDD cases than in those with mild IDD. In addition, we showed that interleukin-1β and tumor necrosis factor-α exposure significantly enhanced circ_0134111 expression in NP cells. Furthermore, ectopic expression of circ_0134111 induced proliferation, pro-inflammatory cytokine secretion, and ECM degradation in the NP cells. We also showed that circ_0134111 directly interacted with microRNA (miR)-578 in NP cells where elevated expression of circ_0134111 enhanced the ADAMTS-5 and MMP-9 expression. Moreover, miR-578 expression was significantly decreased in IDD patients and the miR-578 expression was negatively correlated with circ_0134111 expression in the IDD samples. Interleukin-1β and tumor necrosis factor-α exposure significantly decreased miR-578 levels in NP cells, in which ectopic miR-578 expression inhibited cell growth, pro-inflammatory cytokine expression, and ECM degradation. Finally, we showed that circ_0134111 overexpression induced the IDD-related phenotypic changes through inhibiting miR-578. These data suggested that circ_0134111 could promote the progression of IDD through enhancing aberrant NP cell growth, inflammation, and ECM degradation partly via regulating miR-578.

Turning the Curve Into Straight: Phenogenetics of the Spine Morphology and Coordinate Maintenance in the Zebrafish

The vertebral column, or spine, provides mechanical support and determines body axis posture and motion. The most common malformation altering spine morphology and function is adolescent idiopathic scoliosis (AIS), a three-dimensional spinal deformity that affects approximately 4% of the population worldwide. Due to AIS genetic heterogenicity and the lack of suitable animal models for its study, the etiology of this condition remains unclear, thus limiting treatment options. We here review current advances in zebrafish phenogenetics concerning AIS-like models and highlight the recently discovered biological processes leading to spine malformations. First, we focus on gene functions and phenotypes controlling critical aspects of postembryonic aspects that prime in spine architecture development and straightening. Second, we summarize how primary cilia assembly and biomechanical stimulus transduction, cerebrospinal fluid components and flow driven by motile cilia have been implicated in the pathogenesis of AIS-like phenotypes. Third, we highlight the inflammatory responses associated with scoliosis. We finally discuss recent innovations and methodologies for morphometrically characterize and analyze the zebrafish spine. Ongoing phenotyping projects are expected to identify novel and unprecedented postembryonic gene functions controlling spine morphology and mutant models of AIS. Importantly, imaging and gene editing technologies are allowing deep phenotyping studies in the zebrafish, opening new experimental paradigms in the morphometric and three-dimensional assessment of spinal malformations. In the future, fully elucidating the phenogenetic underpinnings of AIS etiology in zebrafish and humans will undoubtedly lead to innovative pharmacological treatments against spinal deformities.

Circular RNAs in Intervertebral Disc Degeneration: An Updated Review

Low back pain, a common medical condition, could result in severe disability and inflict huge economical and public health burden. Its pathogenesis is attributed to multiple etiological factors, including intervertebral disc degeneration (IDD). Emerging evidence suggests that circular RNAs (circRNAs), a major type of regulatory non-coding RNA, play critical roles in cellular processes that are pertinent to IDD development, including nucleus pulposus cell proliferation and apoptosis as well as extracellular matrix deposition. Increasing number of translational studies also indicated that circRNAs could serve as novel biomarkers for the diagnosis of IDD and/or predicting its clinical outcomes. Our review aims to discuss the recent progress in the functions and mechanisms of newly discovered IDD-related circRNAs.

Emerging roles of circular RNAs in neuropathic pain

Neuropathic pain is a major type of chronic pain caused by the disease or injury of the somatosensory nervous system. It afflicts about 10% of the general population with a significant proportion of patients’ refractory to conventional medical treatment. This highlights the importance of a better understanding of the molecular pathogenesis of neuropathic pain so as to drive the development of novel mechanism‐driven therapy. Circular RNAs (circRNAs) are a type of non‐coding, regulatory RNAs that exhibit tissue‐ and disease‐specific expression. An increasing number of studies reported that circRNAs may play pivotal roles in the development of neuropathic pain. In this review, we first summarize circRNA expression profiling studies on neuropathic pain. We also highlight the molecular mechanisms of specific circRNAs (circHIPK3, circAnks1a, ciRS‐7, cZRANB1, circZNF609 and circ_0005075) that play key functional roles in the pathogenesis of neuropathic pain and discuss their potential diagnostic, prognostic, and therapeutic utilization in the clinical management of neuropathic pain.

The ceRNA PVT1 inhibits proliferation of ccRCC cells by sponging miR-328-3p to elevate FAM193B expression

Clear cell renal cell carcinoma (ccRCC) is a common and fatal malignancy. Long noncoding RNAs (lncRNAs) have emerged as crucial biomarkers and regulators in many cancers, warranting the detailed investigation of their biological functions and molecular mechanisms. In this study, we explored the role and mechanism of plasmacytoma variant translocation 1 (PVT1), a competitive endogenous RNA (ceRNA) in ccRCC tissues in vitro and in vivo. We found that PVT1 is upregulated in ccRCC cells and promoted cell proliferation. Bioinformatic analysis, dual-luciferase reporter assays, argonaute 2-RNA immunoprecipitation (AGO2-RIP), quantitative PCR arrays, western blot assay, and rescue experiments were conducted to explore the underlying mechanisms of PVT1. Our analyses revealed that miR-328-3p was a direct target of PVT1 and that FAM193B was a direct target of miR-328-3p. FAM193B is upregulated in ccRCC tissues and promotes cell proliferation by activating the MAPK/ERK and PI3K/AKT pathways. Our results indicated that PVT1 promotes ccRCC cells proliferation by sponging miR-328-3p to upregulate FAM193B and activate the MAPK/ERK and PI3K/AKT pathways. Collectively, these results suggest that PVT1- miR-328-3p-FAM193B loop could serve as a potential biomarker and therapeutic target for ccRCC.

Severity of Idiopathic Scoliosis Is Associated with Differential Methylation: An Epigenome-Wide Association Study of Monozygotic Twins with Idiopathic Scoliosis

Epigenetic mechanisms may contribute to idiopathic scoliosis (IS). We identified 8 monozygotic twin pairs with IS, 6 discordant (Cobb angle difference > 10°) and 2 concordant (Cobb angle difference ≤ 2°). Genome-wide methylation in blood was measured with the Infinium HumanMethylation EPIC Beadchip. We tested for differences in methylation and methylation variability between discordant twins and tested the association between methylation and curve severity in all twins. Differentially methylated region (DMR) analyses identified gene promoter regions. Methylation at cg12959265 (chr. 7 DPY19L1) was less variable in cases (false discovery rate (FDR) = 0.0791). We identified four probes (false discovery rate, FDR < 0.10); cg02477677 (chr. 17, RARA gene), cg12922161 (chr. 2 LOC150622 gene), cg08826461 (chr. 2), and cg16382077 (chr. 7) associated with curve severity. We identified 57 DMRs where hyper- or hypo-methylation was consistent across the region and 28 DMRs with a consistent association with curve severity. Among DMRs, 21 were correlated with bone methylation. Prioritization of regions based on methylation concordance in bone identified promoter regions for WNT10A (WNT signaling), NPY (regulator of bone and energy homeostasis), and others predicted to be relevant for bone formation/remodeling. These regions may aid in understanding the complex interplay between genetics, environment, and IS.

HOXC13-AS Induced Extracellular Matrix Loss via Targeting miR-497-5p/ADAMTS5 in Intervertebral Disc

Background/Aims: LncRNAs are a new modulator in the development of intervertebral disc degeneration. However, the functional role and mechanism of HOXC13-AS in intervertebral disc degeneration remain unclear. Methods: qRT-PCR analysis was performed to measure the relative expression levels of HOXC13-AS and miR-497-5p, and the levels of IL-1β, IL-6, and TNF-α in the medium supernatant were analyzed by ELISA. The related mechanism between HOXC13-AS and miR-497-5p was detected by luciferase assays. Results: The results revealed that TNF-α and IL-1β induced HOXC13-AS expression in NP cells. HOXC13-AS was overexpressed in IDD specimens compared to control specimens, and higher expression of HOXC13-AS was correlated with high Pfirrmann scores. Ectopic expression of HOXC13-AS promoted MMP-3 and ADAMTS4 and inhibited aggrecan and collagen II expression in NP cells. Furthermore, overexpression of HOXC13-AS increased the expression of inflammatory cytokines, including IL-1β, IL-6, and TNF-α. Our results demonstrated that TNF-α and IL-1β induced ADAMTS5 expression and suppressed miR-497-5p expression. miR-497-5p was downregulated in IDD specimens compared to control specimens, and the lower expression of miR-497-5p was correlated with high Pfirrmann scores. The miR-497-5p level was negatively proportional to HOXC13-AS expression in IDD specimens. Luciferase analysis data indicated that ADAMTS5 was a direct target gene of miR-497-5p. HOXC13-AS induced inflammatory cytokine expression and ECM degradation by modulating miR-497-5p/ADAMTS5. Conclusion: HOXC13-AS may be a treatment target for IDD.

LncRNA BCRT1 facilitates osteosarcoma progression via regulating miR-1303/FGF7 axis

Growing studies noted that lncRNA was closely related with the initiation and progression of tumors. However, the role of BCRT1 in the progression of osteosarcoma remains unknown. We noted that BCRT1 is significantly upregulated in osteosarcoma specimens and cells. Elevated expression of BCRT1 promotes cell growth and cell cycle in osteosarcoma cell. Moreover, BCRT1 induces EMT and secretion of inflammatory mediators in osteosarcoma cell. We illustrated that elevated expression of BCRT1 decreases miR-1303 expression in MG-63 cell. The expression of miR-1303 is lower in osteosarcoma specimens than in non-tumor specimens. There is an inverse interrelation between miR-1303 levels and BCRT1 levels in osteosarcoma specimens. Furthermore, we identified FGF7 is one direct target gene of miR-1303 in osteosarcoma cell. Ectopic expression of miR-1303 suppresses FGF7 expression and elevated expression of BCRT1 enhanced FGF7 expression in MG-63 cell. Finally, we illustrated that BCRT1 induces osteosarcoma cell cycle and proliferation and promotes EMT progression and inflammatory mediators secretion via modulating FGF7 expression. Our study suggested that BCRT1 acts as one oncogene in osteosarcoma progression.

LncRNA RNCR3 promotes endothelial cell proliferation and inflammatory cytokine secretion via regulating miR-185-5p/cyclin D2 axis

Endothelial cell is one critical structure of blood vessels, and irregular migration and proliferation of endothelial cell might cause progression of several vascular diseases such as atherosclerosis and restenosis. We showed that TNF-α, PDGF-bb, and IL-1β promote RNCR3 expression in a dose-dependent manner inhuman endothelial cell. RNCR3 level is higher in serum of atherosclerosis patients compared with those in control volunteers. Overexpression of RNCR3 promotes cell proliferation and three inflammatory cytokine secretion including IL-6, IL-1β, and TNF-α in endothelial cell. We illustrated that overexpression of RNCR3 inhibits miR-185-5p expression in endothelial cell. Furthermore, we indicated that miR-185-5p level is lower in the serum of patients with atherosclerosis compared with those in control volunteers. There is a negative correlation between miR-185-5p and RNCR3 expression in serum of patients with atherosclerosis. Using Targetscan, it predicted that miR-185-5p may bind to cyclin D2 and miR-185-5p is one potential target of miR-185-5p. Luciferase reporter data indicated that miR-185-5p suppresses luciferase value of wild-type cyclin D2 while it has no influence of cyclin D2 mutant. Overexpression of RNCR3 enhances cyclin D2 expression in endothelial cell. Moreover, RNCR3 induces cell growth and enhances inflammatory cytokine secretion through modulating cyclin D2 expression in endothelial cell. These results suggested that RNCR3 may serve as one new target for the treatment of atherosclerosis.

lncRNA RPSAP52 induced the development of tongue squamous cell carcinomas via miR-423-5p/MYBL2

Growing lncRNAs have been noted to involve in the initiation and development of several tumours including tongue squamous cell carcinomas (TSCCs). However, the biological role and mechanism of lncRNA RPSAP52 were not well‐explained. We indicated that RPSAP52 was higher in TSCC samples compared with that in control samples. The higher expression of RPSAP52 was positively correlated with higher T stage and TNM stage. Ectopic expression of RPSAP52 induced TSCC cell growth and cycle and induced cytokine secretion including IFN‐γ, IL‐1β and IL‐6, IL‐8, IL‐10 and TGF‐β. We found that the overexpression of RPSAP52 suppressed miR‐423‐5p expression in SCC‐4 cell. miR‐423‐5p was lower in TSCC samples compared with that in control samples, and miR‐423‐5p level was negatively correlated with higher T stage and TNM stage. Pearson's correlation indicated that miR‐423‐5p was negatively associated with that of RPSAP52 in TSCC tissues. Furthermore, MYBL2 was one direct gene of miR‐423‐5p and elevated expression of miR‐423‐5p suppressed MYBL2 expression and ectopic expression of RPSAP52 increased MYBL2 expression in SCC‐4 cell. Finally, we illustrated that RPSAP52 overexpression promoted TSCC cell growth and cycle and induced cytokine secretion including IFN‐γ, IL‐1β and IL‐6, IL‐8, IL‐10 and TGF‐β via modulating MYBL2. These data provided new insight into RPSAP52, which may be one potential treatment target for TSCC.

LINC00689 induces gastric cancer progression via modulating the miR-338-3p/HOXA3 axis

BACKGROUND

LINC00689 acts one critical regulatory role in several tumors. However, the functional, regulatory mechanism and expression of LINC00689 remains unknown in gastric cancer.

METHODS

LINC00689 and miR-338-3p levels were determined using a quantitative reverse transcriptase-polymerase chain reaction analysis and an enzyme-linked immunoassay and a cell-counting kit-8 assay were utilized to detect interleukin (IL)-8, IL-6 and IL-1β expression and cell proliferation, respectively.

RESULTS

We found that LINC00689 and HOXA3 are overexpressed and miR-338-3p is decreased in gastric cancer cells. Compared to control specimens, LINC00689 is overexpressed in gastric cancer specimens and the level of LINC00689 was up-regulated in 32 cases (32/40; 80.0%) compared to control samples. LINC00689 increased cell growth, epithelial-mesenchymal transition (EMT) development and secretion of inflammatory factors in gastric cancer. Compared to control specimens, miR-338-3p expression was decreased in gastric cancer specimens and a Pearson's correlation assay revealed that miR-338-3p was negatively correlated with LINC00689 expression in gastric cancer specimens. HOXA3 was identified as one target gene of miR-338-3p and Ectopic expression of LINC00689 suppressed miR-338-3p and enhanced HOXA3 expression in HGC-27 cells. LINC00689 enhanced cell growth, EMT development and secretion of inflammatory factors by promoting HOXA3.

CONCLUSIONS

LINC00689 may present a potential future target for gastric cancer treatment.

Dysregulated Bone Metabolism Is Related to High Expression of miR-151a-3p in Severe Adolescent Idiopathic Scoliosis

Adolescent idiopathic scoliosis (AIS) is a common complex disease, and bone homeostasis plays an important role in its pathogenesis. Recent advances in epigenetic research show that dysregulated miRNAs may participate in the development of orthopedic diseases and AIS. The aim of this study was to detect differentially expressed miRNAs in severe AIS and elucidate the mechanism of miRNA deregulation in the pathogenesis of AIS. In the present study, miRNA expression profiles were detected in severe and mild AIS patients as well as healthy controls by miRNA sequencing. Candidate miRNAs were validated in a larger cohort. Primary osteoblasts from severe AIS patients were extracted and isolated to determine the effect of the candidate miRNAs on bone metabolism. Finally, we determined the methylation level in primary osteoblasts from severe AIS patients. The result showed that miR-151a-3p was overexpressed in severe AIS patients. Reduced GREM1 expression was observed in primary osteoblasts from severe AIS patients. miR-151a-3p directly inhibited GREM1 in primary osteoblasts. Relatively lower methylation levels were detected in primary osteoblasts from severe AIS patients. In conclusion, our study revealed that plasma miR-151a-3p levels may serve as a biomarker for severe AIS. Overexpression of miR-151a-3p may interrupt bone homeostasis via inhibiting GREM1 expression. Our result may provide a new biomarker for the early detection of AIS and increase our understanding of the pathogenesis of AIS.

LINC01121 induced intervertebral disc degeneration via modulating miR-150-5p/MMP16 axis

BACKGROUND

Growing evidence indicates that Long noncoding RNAs contribute to cell differentiation, invasion, metabolism, proliferation and metastasis. However, the potential role of LINC01121 in progression of intervertebral disc degeneration (IDD) remains unclear.

METHODS

LINC01121, matrix metalloprotease (MMP)-16 and miR-150-5p expression was determined by a quantitative-reverse transcriptase-polymerase chain reaction assay. Inflammatory cytokines level was measured by an enzyme-linked immunosorbent assay and cell counting kit-8 analysis was used to assess cell proliferation. MMP-16-specific binding with miR-150-5p was verified with a luciferase reporter assay.

RESULTS

We noted that interleukin (IL)-1β and tumor necrosis factor (TNF)-α treatment enhanced LINC01121 and MMP-16 expression in nucleus pulposus (NP) cells. LINC01121 was higher in IDD specimens compared to that in control specimens. Higher expression of LINC01121 was correlated with disc degeneration degree. Ectopic expression of LINC01121 enhanced cell proliferation and promoted ki-67, MMP-3 and ADAMTS5 expression and also suppressed collagen II expression in NP cells. We observed that overexpression of LINC01121 increased the secretion of three inflammatory cytokines, including IL-6, TNF-α and IL-1β. We found that ectopic expression of LINC01121 decreased the miR-150-5p level in NP cells. Luciferase reporter data confirmed that MMP-16 was one direct target of miR-150-5p. Overexpression of miR-150-5p inhibited MMP-16 level and elevated the expression of LINC01121 enhanced MMP-16 level. We also found that MMP-16 was up-regulated in IDD specimens compared to that in control specimens. Higher expression of MMP-16 was correlated with disc degeneration degree. Interestingly, MMP-16 expression was positively related to LINC01121 in IDD specimens. Finally, overexpression of LINC01121 regulated cell growth, extracellular matrix degradation and inflammatory cytokine secretion via modulating MMP-16.

CONCLUSIONS

our data suggested LINC01121 may be a new therapeutic target for IDD.

Emerging roles of non-coding RNAs in scoliosis

Scoliosis, a complex three‐dimensional deformity of the spine with the Cobb angle (a measure of the spinal lateral curvature) >10 degree, encompasses a spectrum of pathologies, including congenital, idiopathic, syndromic and neuromuscular aetiologies. The pathogenesis is multifactorial involving both environmental and genetic factors but the exact cellular and molecular mechanisms of disease development remain largely unknown. Emerging evidence showed that non‐coding RNAs (ncRNAs), namely microRNAs, long ncRNAs and circular RNAs, are deregulated in many orthopaedic diseases, including scoliosis. Importantly, these deregulated ncRNAs functionally participate in the initiation and progression of scoliosis. Here, we review recent progress in ncRNA research on scoliosis.