A single-nucleotide polymorphism in MMP9 is associated with decreased risk of steroid-induced osteonecrosis of the femoral head

Gene expression profiling of peripheral blood in patients with steroid-induced osteonecrosis of the femoral head

Aim: Steroid-induced osteonecrosis of the femoral head (SONFH) is a severe complication following glucocorticoid therapy. This study aimed to identify the differential mRNA expression and investigate the molecular mechanisms of SONFH. Materials & methods: RNA sequencing was performed in eight SONFH patients, five non-SONFH patients and five healthy individuals. Results: A total of 1555, 3997 and 5276 differentially expressed mRNAs existed between the following combinations: SONFH versus non-SONFH, SONFH versus healthy subjects and non-SONFH versus healthy subjects. Increased ISM1 expression might contribute to a high risk of SONFH through antiangiogenesis. Decreased FOLR3 expression might affect the metabolism of homocysteine, leading to avascular necrosis of the femoral head. KCNJ2, which plays a pivotal role in regulating bone development, was also deregulated. Conclusion: ISM1, FOLR3 and KCNJ2 might be related to the occurrence of SONFH.

MIR31HG polymorphisms are related to steroid-induced osteonecrosis of femoral head among Chinese Han population

Backgrounds

MIR31 host gene (MIR31HG) polymorphisms play important roles in the occurrence of osteonecrosis. However, the association of MIR31HG polymorphisms with the risk of steroid-induced osteonecrosis of the femoral head (SONFH) remains unclear. In this study, we aimed to investigate the correlation between MIR31HG polymorphisms and SONFH susceptibility in the Chinese Han population.

Methods

A total of 708 volunteers were recruited to detect the effect of seven single nucleotide polymorphisms (SNPs) in the MIR31HG gene on SONFH risk in the Chinese Han population. Genotyping of MIR31HG polymorphisms was performed using the Agena MassARRAY platform. The odds ratio (OR) and 95% confidence interval (95% CI) were used to evaluate the correlation between MIR31HG polymorphisms and SONFH risk using logistic regression model.

Results

According to the results of genetic model, rs10965059 in MIR31HG was significantly correlated with the susceptibility to SONFH (OR = 0.56, p = 0.002). Interestingly, the stratified analysis showed that rs10965059 was associated with the reduced risk of SONFH in subjects aged > 40 years (OR = 0.30, p < 0.001) and male populations (OR = 0.35, p < 0 .001). Moreover, rs10965059 was associated with the reduced risk of bilateral SONFH (OR = 0.50, p = 0.002). Finally, multi-factor dimension reduction (MDR) results showed that the combination of rs1332184, rs72703442, rs2025327, rs55683539, rs2181559, rs10965059 and rs10965064 was the best model for predicting SONFH occurrence (p < 0.0001).

Conclusion

The study indicated that rs10965059 could be involved in SONFH occurrence in the Chinese Han population, which might provide clues for investigating the role of MIR31HG in the pathogenesis of SONFH.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05785-w.

Steroid-induced osteonecrosis

Osteonecrosis associated with the use of glucocorticoids is a severe, potentially debilitating complication. In broader terms, it commonly involves the femoral head with secondary hip osteoarthritis. Osteonecrosis can also be caused by trauma and other non-traumatic factors besides steroid treatment. Nonetheless, glucocorticoid use is frequently observed in clinical settings in which this represents a common therapeutic option, including general practice, rheumatology and clinical immunology, among others. The pathogenesis involves genetic components, vascular impairment, adipocyte hypertrophy, and increased intraosseous pressure, ultimately leading to marrow and bone ischemia and necrosis and the process rapidly becomes irreversible. Osteonecrosis manifests with pain and impaired motility while the diagnosis is usually made with magnetic resonance imaging allowing early detection and potentially (dependent on the patient's needs for steroids and stage) timely management with conservative options, followed by joint replacement at late stages. In this review we discuss the pathogenesis, risk factors, diagnosis, staging, and management of this complication associated with glucocorticoid treatment.

Association of Specific Genetic Polymorphisms with Atraumatic Osteonecrosis of the Femoral Head: A Narrative Review

INTRODUCTION

Atraumatic ONFH is one of the leading cause of hip morbidity in the working-age group. It is a multi-factorial disease whose root cause can be attributed to single-nucleotide polymorphism. Identifying such polymorphisms could pave the way for new modalities of treatment for ONFH.

METHODOLOGY

Two databases were electronically searched for relevant articles. The articles were screened through titles, abstract and full texts to include the relevant studies. A secondary search was done through the reference list of selected articles.

RESULTS

A total of 52 studies were included among the 181 hits. All 181 were case-control studies. Summary of these studies identifies multiple SNPs which can cause ONFH. There were 117 SNPs in all 181 studies, of which 92 were associated with the causation of ONFH and 25 were protective against ONFH.

CONCLUSION

SNPs play an essential role in causing atraumatic ONFH. Identification of SNP that contribute to causing ONFH may help reduce the disease burden by early identification, diagnosis and treatment, including targeted gene therapy.

Role of miR-214 in biomaterial transplantation therapy for osteonecrosis

BACKGROUND

The effectiveness and availability of conservative therapies for osteonecrosis of the femoral head (ONFH) are limited. Transplantation of bone marrow mesenchymal stem cells (BMSCs) combined with Bio-Oss, which is a good bone scaffold biomaterial for cell proliferation and differentiation, is a new potential therapy. Of note, the expression of miRNAs was significantly modified in cells cultured with Bio-Oss, and MiR-214 was correlated positively with osteonecrosis. Furthermore, miR-214 was upregulated in cells exposed to Bio-Oss.

OBJECTIVE

To investigate whether targeting miR-214 further improves the transplantation effect.

METHODS

We treated BMSCs with agomiR-214 (a miR-214 agonist), antagomiR-214 (a miR-214 inhibitor), or vehicle, followed by their transplantation into ONFH model rats.

RESULTS

Histological and histomorphometric data showed that bone formation was significantly increased in the experimental groups (Bio-Oss and BMSCs treated with antagomiR-214) compared with other groups.

CONCLUSIONS

miR-214 participates in the inhibition of osteoblastic bone formation, and the inhibition of miR-214 to bone formation during transplantation therapy with Bio-Oss combined with BMSCs for ONFH.

Association between Genetic Polymorphisms of MIR3142HG and the Risk of Steroid-Induced Osteonecrosis of the Femoral Head in the Population of Northern China

BACKGROUND

Steroid-induced osteonecrosis of the femoral head (ONFH) is aseptic necrosis of the femoral head caused by glucocorticoid use. Once necrotic femoral head necrosis occurs, it irreversibly affects the quality of life seriously. Studies have shown that the susceptibility to steroid-induced ONFH is likely to be related to the variation of miRNA-coding genes. Therefore, this study aimed was to investigate the effect of MIR3142HG on steroid-induced ONFH.

METHODS

Agena MassARRAY was used to genotype MIR3142HG gene rs1582417, rs2431689, rs7727155, and rs17057846 in 199 patients and 725 healthy people. A genetic model and haplotype analysis were used to evaluate the relationship between the MIR3142HG polymorphism and the risk of steroid-induced ONFH. The odds ratio and 95% confidence intervals were obtained through logistic regression to assess the influence of gene polymorphisms on the occurrence of steroid-induced ONFH.

RESULTS

The consequences show that rs7727115 is a protective factor, it could reduce the risk of steroid-induced ONFH, and rs1582417 could increase the risk of steroid-induced ONFH. In the genetic model, rs1582417 was associated with increased risk of alcohol-induced ONFH in dominant model and log-additive model. rs7727115 showed a decreased risk in codominant model, dominant model, and log-additive model. In addition, rs2431689 is related to HDL-C (p = 0.012) and ApoA1 (p = 0.010) levels, and rs17057846 (p = 0.024) is related to ApoB levels. Thelinkage analysis indicated 3 single-nucleotide polymorphisms (rs2431689, rs7727115, and rs17057846) in MIR3142HG with significant chain imbalance. In addition, haplotype "GGG" of MIR3142HG was found out and is harmful for steroid-induced ONFH.

CONCLUSION

Our results first confirm that the genetic polymorphism of MIR3142HG is associated with steroid-induced ONFH susceptibility in Chinese Han population.

Bioinformatics analysis and identification of genes and molecular pathways in steroid-induced osteonecrosis of the femoral head

Background

Steroid-induced osteonecrosis of the femoral head (ONFH) is a common hip joint disease and is difficult to be diagnosed early. At present, the pathogenesis of steroid-induced ONFH remains unclear, and recognized and effective diagnostic biomarkers are deficient. The present study aimed to identify potentially important genes and signaling pathways involved in steroid-induced ONFH and investigate their molecular mechanisms.

Methods

Microarray data sets GSE123568 (peripheral blood) and GSE74089 (cartilage) were obtained from the Gene Expression Omnibus database, including 34 ONFH samples and 14 control samples. Morpheus software and Venn diagram were used to identify DEGs and co-expressed DEGs, respectively. Besides, we conducted Kyoto Encyclopedia of Genome (KEGG) and gene ontology (GO) pathway enrichment analysis. We construct a protein-protein interaction (PPI) network through GEO2R and used cytoHubba to divide the PPI network into multiple sub-networks. Additionally, quantitative real-time polymerase chain reaction (qRT-PCR) was performed to verify the bioinformatics analysis results.

Results

A total of 118 intersecting DEGs were obtained between the peripheral blood and cartilage samples, including 40 upregulated genes and 78 downregulated genes. Then, GO and KEGG pathway enrichment analysis revealed that upregulated DEGs focused on the signaling pathways related to staphylococcus aureus infection, leishmaniasis, antigen processing, and presentation, as well as asthma and graft-versus-host disease. Downregulated genes were concentrated in the FoxO signaling pathway, AMPK signaling pathway, signaling pathway regulating stem cell pluripotency, and mTOR signaling pathway. Some hub genes with high interactions such as CXCR1, FPR1, MAPK1, FOXO3, FPR2, CXCR2, and TYROBP were identified in the PPI network. The results of qRT-PCR demonstrated that CXCR1, FPR1, and TYROBP were upregulated while MAPK1 was downregulated in peripheral blood of steroid-induced ONFH patients. This was consistent with the bioinformatics analysis.

Conclusions

The present study would provide novel insight into the genes and associated pathways involved in steroid-induced ONFH. CXCR1, FPR1, TYROBP, and MAPK1 may be used as potential drug targets and biomarkers for the diagnosis and prognosis of steroid-induced ONFH.

ARCO Consensus on the Pathogenesis of Non-traumatic Osteonecrosis of the Femoral Head

Osteonecrosis of the femoral head (ONFH) is a devastating disease frequently leading to femoral head collapse and hip arthritis. Specifically, non-traumatic ONFH primarily affects young and middle-aged adults. Although compromised local circulation of the femoral head seems to be pathognomonic for the disease, the pathogenesis is perplexing and continues to be an area of scrutiny and research. Comprehension of the pathogenesis is of crucial importance for developing and guiding treatments for the disease. Therefore, we provide an up-to-date consensus on the pathogenesis of non-traumatic ONFH.

Variants in RETN gene are associated with steroid-induced osteonecrosis of the femoral head risk among Han Chinese people

Background

Gene polymorphism has an important influence on RETN gene expression level, and the increased level of resistin encoded in RETN will lead to metabolic disorder, especially lipid metabolism. Moreover, steroid-induced osteonecrosis of the femoral head (steroid-induced ONFH) is closely related to lipid metabolism level, so this study is intended to explore the relationship of RETN polymorphisms with susceptibility to steroid-induced ONFH in the Chinese Han population.

Methods

In this case-control study, eight single-nucleotide polymorphisms (SNPs) of RETN were genotyped by the Agena MassARRAY system in 199 steroid-induced ONFH patients and 200 healthy controls. The relationship between RETN polymorphisms and steroid-induced ONFH risk was assessed using genetic models and haplotype analyses. Odds ratio (OR) and 95% confidence intervals (CIs) were obtained by logistic regression adjusted for age.

Results

We found significant differences in the distribution of HDL-C, TG/HDL-C, and LDL-C/HDL-C between the patients and the control group (p < 0.05). In allele model and genotype model analysis, rs34861192, rs3219175, rs3745368, and rs1477341 could reduce the risk of steroid-induced ONFH. Further stratified analysis showed that rs3745367 was related to the clinical stage of patients, and rs1477341 was significantly correlated with an increased TG level and a decreased TC/HDL-C level. The linkage analysis showed that two SNPs (rs34861192 and rs3219175) in RETN even significant linkage disequilibrium.

Conclusions

Our results provide the firstly evidence that RETN gene polymorphisms were associated with a reduced risk of steroid-induced ONFH in Chinese Han population.

Peripheral Blood Stem Cell Therapy Does Not Improve Outcomes of Femoral Head Osteonecrosis With Cap-Shaped Separated Cartilage Defect

A combination treatment with porous tantalum rod implantation and intra-arterial infusion of peripheral blood stem cells (PBSCs) provides a promise for treating early and intermediate stages of osteonecrosis of the femoral head (ONFH). However, its clinical indications and application restrictions remain unclear. This study aims to determine the clinical, histological, and radiological outcomes of a combination treatment using mechanical support and a targeted intra-arterial infusion of PBSCs for painful ONFH with a cap-shaped separation (CSS) cartilage defect. Compared with the standard pain management (control group), this combination treatment did not improve the Harris Hip Score (HHS) at 36 months. Micro-CT and histologic analyses showed severe focal destruction in all CSS-ONFH femoral heads in both the combination and control groups. Femoral heads showed a higher percentage of bone lesions in the combination treatment group than in the control group. There was no significant difference in osteoclast number in the subchondral bone areas between the two groups. A high level of expression of inflammatory cytokines, including tumor necrosis factor-α and interleukin-1β, was detected in blood vessels around the subchondral bone in both groups. The RANKL/OPG (receptor activator of the nuclear factor-kB ligand/osteoprotegerin) ratio was also similar between the control and combination treatment groups. Our results indicate that this combination treatment is not an effective method for the treatment of patients with painful CSS-ONFH. Moreover, this combination treatment did not inhibit inflammatory osteoclastogenesis in patients with more advanced disease. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:269-276, 2020.

MMP2 and MMP10 Polymorphisms Are Related to Steroid-Induced Osteonecrosis of the Femoral Head among Chinese Han Population

Background

Steroid-induced osteonecrosis of the femoral head is a relatively serious condition which seriously reduces patient quality of life. However, the pathogenesis of steroid-induced ONFH is still unclear. In recent years, more scholars have found that the pathogenesis of steroid-induced ONFH is related to susceptibility factors such as MMPs/TIMPs system. The main purpose of this study is to investigate the correlation between MMP2 and MMP10 gene polymorphisms and steroid-induced ONFH in Chinese Han population.

Methods

Six SNPs in MMP2 and two SNPs in MMP10 were genotyped using Agena MassARRAY RS1000 system from 286 patients of steroid-induced ONFH and in 309 healthy controls. The association between MMP2 and MMP10 polymorphisms and steroid-induced ONFH risk were estimated by the Chi-squared test, genetic model analysis, haplotype analysis, and stratification analysis. The relative risk was estimated by odd ratios (ORs) and 95% confidence intervals (CIs).

Result

We found that the minor TG allele of rs470154 in MMP10 was associated with an increased risk of steroid-induced ONFH (OR = 1.45, 95% CI, 1.03 – 2.05, p = 0.032). In the genetic model analysis, we found that rs2241146 in MMP2 gene and rs470154 in MMP10 gene showed a statistically significant association with increased risk of steroid-induced ONFH. The six SNPs (rs470154, rs243866, rs243864, rs865094, rs11646643, and rs2241146) showed a statistically significant association with different clinical phenotypes.

Conclusion

Our results verify that genetic polymorphisms of MMP2 and MMP10 contribute to steroid-induced ONFH susceptibility in the population of Chinese Han population, and our study provides new insights into the role that MMP2 and MMP10 plays in the mechanism of ONFH.

Discovery and validation an eight-biomarker serum gene signature for the diagnosis of steroid-induced osteonecrosis of the femoral head

Steroid-induced osteonecrosis of the femoral head (SONFH) is difficult to be diagnosed at the early stages when it can be administrated effectively. Yet, to date no study has been performed to identify diagnostic biomarkers and to develop diagnostic models for SONFH. In the current study, a total of 60 SONFH patients with Association Research Circulation Osseous (ARCO) stages I-IV, and 20 controls were enrolled and divided into the discovery and validation cohorts. The serum samples were collected and the gene expression profiles were detected by microarray analysis based on the discovery cohort. Then, eight genes (BIRC3, CBL, CCR5, LYN, PAK1, PTEN, RAF1 and TLR4) were identified as the candidate serum biomarkers of SONFH due to the significant differential expression patterns and the topological importance in the interaction network of SONFH-related differentially expressed genes. Functionally, these candidate serum biomarkers were significantly involved into several pathological processes during SONFH progression, such as the immune regulation and inflammation, bone metabolism and angiogenesis. After that, a prediction model for the diagnosis of SONFH was constructed using Partial least squares regression based on the serum levels of the candidate biomarkers. Notably, both the 10-fold cross-validation and the independent dataset test demonstrated the good performance of this model. In conclusion, our study discovered eight promising serum biomarkers and developed the multi-biomarker-based prediction model as a new, potential and non-invasive diagnostic tool for the detection of SONFH, as well as benefit the administration of SONFH in a daily clinical setting.

MMP-14 single-nucleotide polymorphisms are related to steroid-induced osteonecrosis of the femoral head in the population of northern China

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a refractory disease which frequently occurs in young and middle-aged people. Recent studies indicated that MMP-14 played an important role in the development of chondrocytes, metabolism of osteoblasts as well as fate decision of hypertrophic chondrocytes. The aim of this study was to investigate the association between polymorphisms of MMP-14 and steroid-induced osteonecrosis of the femoral head in the Chinese population.

METHODS

We selected 7 SNPs (rs3751488, rs1003349, rs1042703, rs2236302, rs1042704, rs2236303, and rs2236304) on gene MMP-14. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using the chi-squared test, genetic model analysis, haplotype analysis, and stratification analysis.

RESULTS

We discovered that the genotype "G/G" of rs2236302 was associated with ONFH risk in the MMP-14 in the codominant model (OR = 8.62, 95% CI = 1.07-69.46, p = 0.038) and recessive model (OR = 8.86, 95% CI = 1.10-71.31, p = 0.013).

CONCLUSIONS

We have confirmed that the susceptive SNPs (rs2236302) of MMP-14 from the MMPs/TIMPs system exhibit a significant association with increased risk of steroid-induced ONFH in the population of northern China.

Osteogenic effect of bone marrow mesenchymal stem cell-derived exosomes on steroid-induced osteonecrosis of the femoral head

BACKGROUND

Animal studies have demonstrated the therapeutic effect of mesenchymal stem cells (MSCs) on osteogenesis, but little is known about the functions of exosomes (Exos) released by bone MSCs (BMSCs). Here, we investigated the effect of BMSC Exos on steroid-induced femoral head necrosis (SFHN) and explored the vital genes involved in this process.

MATERIALS AND METHODS

BMSCs were isolated from healthy and SFHN rats. BMSC Exos were isolated using the Exosome Precipitation Kit and characterized by transmission electron microscopy and Western blotting. SFHN BMSCs were incubated with Exos from healthy BMSCs. Osteogenic ability was assessed by oil red O staining and alizarine red staining. Differentially expressed genes (DEGs) induced by Exos were screened using the Osteogenesis RT2 Profiler PCR Array. The effect of upregulated Sox9 was examined using lentivirus-mediated siRNA.

RESULTS

The results revealed that BMSC Exos were 100-150 nm in size and expressed CD63. Moreover, BMSC Exo-treated SFHN cells exhibited suppressed adipogenesis compared to model cells. PCR array showed that eleven and nine genes were upregulated and downregulated, respectively, in the BMSC Exo-treated SFHN cells compared to the model group. Among the DEGs, osteogenesis-related genes, including Bmp2, Bmp6, Bmpr1b, Mmp9, and Sox9, may play important roles in SFHN. Furthermore, the DEGs were mainly involved in immune response, osteoblast differentiation, and in the transforming growth factor-β/bone morphogenetic protein signaling pathway. The level of the SOX9 protein was upregulated by Exos, and Sox9 silencing significantly decreased the osteogenic effect of BMSC Exos.

CONCLUSION

Our data suggest that Exos derived from BMSCs mainly affect SFHN osteogenesis, and this finding can be further investigated to develop a novel therapeutic agent for SFHN.

Osteonecrosis of the femoral head: genetic basis

PURPOSE

Genetic factors and hereditary forms of osteonecrosis of the femoral head (ONFH) have been elucidated through genetic association studies. The significance of these cases is that they suggest an alternative hypothesis to the development of the disease. This review presents a summary of single nucleotide polymorphisms (SNPs) and other genetic mutation variations found in association with ONFH, including our recent identification of a novel mutation in the transient receptor potential vanilloid 4 (TRPV4) gene in association with inherited ONFH. The purpose of this review is to consolidate and categorize genetic linkages according to physiological pathways.

METHODS

A systematic review of literature from PubMed and Google Scholar was undertaken with a focus on genetic linkages and hereditary case studies of the disease. Recent genetic analysis studies published after 2007 were the focus of genetic linkages in non-hereditary cases.

RESULTS

The summary of these genetic findings identifies biological processes believed to be involved in the development of ONFH, which include circulation, steroid metabolism, immunity, and the regulation of bone formation.

CONCLUSION

Taken together, these associations may lead to new pathways of bone repair and remodeling while opening new avenues for therapeutic targets. Knowledge of genetic variations could help identify individuals considered to be at higher risk of developing ONFH and prevent the multiple hit effect.

Association of MMP-8 rs2012390 and rs11225394 polymorphisms with osteonecrosis of the femoral head risks: Evidence from a meta-analysis

BACKGROUND

The association of MMP-8 rs2012390 and rs11225394 polymorphisms with osteonecrosis of the femoral head (ONFH) risks was investigated in several studies with conflicting results. We performed the meta-analysis to evaluate the association between them.

METHODS

Potentially relevant literatures were searched from the electronic databases of PubMed, Web of Science, and Cochrane Library. All databases were searched up to May 6, 2018. The strength of associations of the MMP-8 rs2012390 and rs11225394 polymorphisms with ONFH risk was assessed by crude odds ratios (ORs) with their 95% confidence intervals (CIs) under different genetic models.

RESULTS

A total of 1469 cases diagnosed with ONFH and 1211 healthy controls were included in the current meta-analysis. A remarkable association between rs11225394 in the MMP-8 gene and an increased risk of ONFH was found (allele model: OR = 1.33, 95% CI = 1.09-1.61, P = .005; heterozygote model: OR = 1.39, 95% CI = 1.13-1.71, P = .002; dominant model: OR = 1.40, 95% CI = 1.14-1.73, P = .002, respectively). Meanwhile, a significant association between MMP-8 rs2012390 and the decreased risk of ONFH was found in heterozygote model (OR = 0.63, 95% CI = 0.51-0.77, P < .00001).

CONCLUSION

The meta-analysis results showed a remarkable association between rs11225394 in MMP-8 gene and an increased risk of ONFH and a significant association between MMP-8 rs2012390 and the decreased risk of ONFH.

Differential expression of miR-195-5p in collapse of steroid-induced osteonecrosis of the femoral head

Background

Femoral head collapse is a key reference point for determining a treatment regimen of femoral head osteonecrosis. However, there are no effective preventive measures and the efficacy of hip-preserving surgery is unsatisfactory due to the unclear mechanism of collapse. This study aimed to identify and validate miRNAs differentially expressed in collapse and non-collapse areas of the osteonecrotic femoral head, and to predict the target genes and pathways of these miRNAs.

Results

Nine samples passed the quality control test. A total of 2085 differentially expressed miRNAs were detected, among which 433 miRNAs showed differential expression in the T1 group compared to the W1 group; 344 miRNAs showed differential expression in the T2 group compared to the W2 group; 107 miRNAs showed differential expression in the T3 group compared to the W3 group. After combining data from all three patients, 10 miRNAs showed differential expression in the collapse area (T1+T2+T3) compared to the non-collapse area (W1+W2+W3). Compared to the normal area, has-miR-195-5p showed the most significant downregulation. Expression results from RT-PCR revealed that the expression of hsa-miR-195-5p in the collapse area (T1+T2+T3) was significantly lower than that in the non-collapse area (W1+W2+W3) and normal area (Z1+Z2+Z3). 157 genes were perdicted as the target gene of hsa-miR-195-5p.

Materials and Methods

Femoral heads of three patients (2 males and 1 female) treated by total hip arthroplasty surgery for steroid-induced femoral head osteonecrosis were selected based on inclusion and exclusion criteria. Bone tissue samples were obtained from the collapse area (T), non-collapse area (W), and normal area (Z) according to the anatomical structure of osteonecrotic femoral heads. Total RNA was extracted from the samples and the microarray chip was scanned. miRNAs showing differential expressions of more than 1.5-fold were selected and was validated by RT-PCR. TargetScan, mirBase and miRanda bioinformatics software was used to predict target genes and identify possible pathways involving these genes.

Conclusions

miR-195-5p showed the most significant difference in the collapse area of osteonecrotic femoral heads, suggesting that collapse may be related to the downregulation of miR-195-5p.

Circulating microRNA signature of steroid-induced osteonecrosis of the femoral head

OBJECTIVES

Steroid-induced osteonecrosis of the femoral head (ONFH) is a common orthopaedic disease of which early detection remains clinically challenging. Accumulating evidences indicated that circulating microRNAs (miRNAs) plays vital roles in the development of several bone diseases. However, the association between circulating miRNAs and steroid-induced ONFH remains elusive.

MATERIALS AND METHODS

miRNA microarray was performed to identify the differentially abundant miRNAs in the serums of systemic lupus erythematosus (SLE) patients with steroid-induced ONFH as compared with SLE control and healthy control group. We predicted the potential functions of these differentially abundant miRNAs using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses and reconstructed the regulatory networks of miRNA-mRNA interactions.

RESULTS

Our data indicated that there were 11 differentially abundant miRNAs (2 upregulated and 9 downregulated) between SLE-ONFH group and healthy control group and 42 differentially abundant miRNAs (14 upregulated and 28 downregulated) between SLE-ONFH group and SLE control group. We also predicted the potential functions of these differentially abundant miRNAs using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses and reconstructed the regulatory networks of miRNA-mRNA interactions.

CONCLUSIONS

These findings corroborated the idea that circulating miRNAs play significant roles in the development of ONFH and may serve as diagnostic markers and therapeutic targets.

Emerging roles of MicroRNAs in osteonecrosis of the femoral head

Osteonecrosis of the femoral head (ONFH) is one of the most common orthopaedic diseases. The exact pathogenic mechanism of ONFH is still unknown. MicroRNAs (miRNAs) are a class of non-coding RNAs that negatively modulate gene expression at post-transcriptional level. An increasing number of studies have shown that miRNAs play crucial roles in different physiological processes, including development, cell proliferation, differentiation and metabolism. Recently, multiple studies demonstrated that miRNAs are involved in the pathogenesis of ONFH. In this review, we summarize dysregulated miRNAs and their functions in ONFH. Furthermore, we discuss their potential clinical applications for diagnosis and treatment of ONFH.

The relationship between genetic polymorphisms in apolipoprotein E (ApoE) gene and osteonecrosis of the femoral head induced by steroid in Chinese Han population

Previous studies suggested that apolipoprotein E (ApoE) genetic polymorphisms (SNPs) may result in abnormal lipid metabolism. Therefore, genetic polymorphisms in ApoE may be associated with the occurrence of osteonecrosis of the femoral head (ONFH). A case control study was designed to include 580 patients with steroid-induced ONFH and 560 age- and sex-matched non steroid-induced ONFH control subjects to analyze the association between ApoE polymorphisms and susceptibility of steroid-induced ONFH. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was utilized to differentiate two genotypes SNPs (rs7412 C/T and rs429358 T/C) in ApoE gene. Both rs7412 C/T and rs429358 T/C were found to be associated with the risk of steroid-induced ONFH. However, no significant association was observed between the haplotypes T-T, T-C and C-C in ONFH. Furthermore, T allele of rs7412 and C allele of rs429358 carriers were associated with higher levels of TG in steroid-induced ONFH patients (P < 0.05). The study suggested that ApoE genetic polymorphisms conferred susceptibility to steroid-induced ONFH in Chinese Han population. However, the results need further investigation with large sample size and various populations.

MMP9 polymorphism is associated with susceptibility to non-traumatic osteonecrosis of femoral head in a Chinese Han population

Non-traumatic osteonecrosis of femoral head (ONFH) is an orthopedic refractory disease with escalating morbidity in Chinese Han population. In our case-control study, we examined eight previously identified MMP9 single-nucleotide polymorphisms (SNPs) in 585 non-traumatic ONFH patients and 507 healthy individuals from northern China to determine whether these SNPs associated with the risk of developing non-traumatic ONFH. Genetic model and haplotype analyses were used to evaluate the association between SNPs and non-traumatic ONFH. MMP9 rs2274755 (OR, 0.740; 95% CI, 0.578-0.949; p = 0.017) was associated with a reduced risk of non-traumatic ONFH. After adjusting for age and gender, the logistic regression results showed that rs2274755 associated with a lower risk of non-traumatic ONFH in the dominant (OR=0.71, 95% CI: 0.54-0.94, p=0.016), overdominant (OR=0.73, 95% CI: 0.55-0.96, p=0.026) and log-additive (OR=0.74740; 95% CI, 0.578-0.949; p=0.017) models. In addition, the “TGC” haplotype of rs2274755 was associated with a 0.79-fold decrease in risk while the “CTC” haplotype associated with a 0.65-fold decrease risk of the non-traumatic ONFH. These results provide evidence that the MMP9 SNP at the rs2274755 locus is associated with a decreased risk of non-traumatic ONFH in a Chinese Han population.