Circular RNA CircSLC8A1 contributes to osteogenic differentiation in hBMSCs via CircSLC8A1/miR-144-3p/RUNX1 in periprosthetic osteolysis.

Circular RNAs (circRNAs) are often found in eukaryocyte and have a role in the pathogenesis of a variety of human disorders. Our related research has shown the differential expression of circRNAs in periprosthetic osteolysis (PPOL). However, the involvement of circRNAs in the exact process is yet unknown. CircSLC8A1 expression was evaluated in clinical samples and human bone marrow mesenchymal stem cells (hBMSCs) in this investigation using quantitative real-time PCR. In vitro and in vivo studies were conducted to explicate its functional role and pathway. We demonstrated CircSLC8A1 is involved in PPOL using gain- and loss-of-function methods. The association of CircSLC8A1 and miR-144-3p, along with miR-144-3p and RUNX1, was predicted using bioinformatics. RNA pull-down and luciferase assays confirmed it. The impact of CircSLC8A1 in the PPOL-mouse model was also investigated using adeno-associated virus. CircSLC8A1 was found to be downregulated in PPOL patients' periprosthetic tissues. Overexpression of CircSLC8A1 promoted osteogenic differentiation (OD) and inhibited apoptosis of hBMSCs in vitro. The osteogenic markers of RUNX1, osteopontin (OPN) and osteocalcin (OCN) were significantly upregulated in hBMSCs after miR-144-3p inhibitor was transferred. Mechanistic analysis demonstrated that CircSLC8A1 directly bound to miR-144-3p and participated in PPOL through the miR-144-3p/RUNX1 pathway in hBMSCs. Micro-CT and quantitative analysis showed that CircSLC8A1 markedly inhibited PPOL, and osteogenic markers (RUNX1, OPN and OCN) were significantly increased (P<0.05) in the mice model. Our findings prove that CircSLC8A1 exerted a regulatory role in promoting osteogenic differentiation in hBMSCs, and CircSLC8A1/miR-144-3p/RUNX1 pathway may provide a potential target for prevention of PPOL.

Effects of Estrogen on Proliferation and Apoptosis of Osteoblasts through Regulating GPER/AKT Pathway.

This experiment was carried out to study the effects of estrogen on the proliferation and apoptosis of osteoblasts through regulating the G protein-coupled estrogen receptor (GPER)/protein kinase B (AKT) pathway. For this aim, osteoblasts were cultured in vitro and divided into control group, estrogen group and inhibitor group after passage. The osteoblasts in the control group were cultured normally, estrogen intervention was made in the estrogen group and G15 inhibitor intervention was made in the inhibitor group. After intervention for 24 h, osteoblasts were collected for detection. The positive expression of GPER and the double-positive expression of Tom20/Lamp2 were detected via immunofluorescence assay. The protein expressions of GPER, AKT and phosphorylated (p)-AKT were detected via Western blotting. The mRNA expression of GPER was detected via qPCR. Moreover, the autophagosomes were observed under a transmission electron microscope, and the apoptosis and cell proliferation were detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and cell counting kit-8 (CCK8) assay, respectively. Results of the immunofluorescence assay revealed that the positive expression of GPER in the estrogen group was higher than that in the control group and inhibitor group (p<0.05), while the double-positive expression of Tom20/Lamp2 in the estrogen group was lower than that in control group and inhibitor group (p<0.05). According to the results of Western blotting, the relative protein expression of AKT had no differences among the three groups (p>0.05), while the relative protein expressions of GPER and p-AKT in the estrogen group were higher than those in the control group and inhibitor group (p<0.05). The results of qPCR showed that the relative mRNA expression of GPER in the estrogen group was higher than that in the control group and inhibitor group (p<0.05). There were a small number of autophagosomes in osteoblasts in the control group and inhibitor group, while the number of autophagosomes in osteoblasts was smaller in the estrogen group. Besides, the estrogen group had a remarkably lower apoptosis rate of osteoblasts than the control group and inhibitor group and a remarkably higher proliferation rate than the control group and inhibitor group. Then estrogen can inhibit the mitochondrial autophagy of osteoblasts by regulating the GPER/AKT pathway, thereby inhibiting apoptosis and promoting cell proliferation.

Interleukin-10 family members: Biology and role in the bone and joint diseases.

Interleukin (IL)-10 family cytokines include IL-10, IL-19, IL-20, IL-22, IL-24, IL-26, IL-28A, IL-28B, and IL-29. These cytokines play crucial regulatory roles in various biological reactions and diseases. In recent years, several studies have shown that the IL-10 family plays a vital role in bone and joint diseases, including bone metabolic diseases, fractures, osteoarthritis, rheumatoid arthritis, and bone tumors. Herein, the recent progress on the regulatory role of IL-10 family of cytokines in the occurrence and development of bone and joint diseases has been summarized. This review will provide novel directions for immunotherapy of bone and joint diseases.

Are additional screws required for press-fit fixation of cementless acetabular cups? A systematic review and meta-analysis.

BACKGROUND: Press-fit cementless acetabular cup is widely used in total hip arthroplasty (THA). However, the use of additional screws for the acetabular cup has been extensively debated. The purpose of this review is to compare the stability, revision rate, wear rate, and clinical scores of cementless acetabular cups with and without screws in THA. MATERIALS AND METHODS: Comprehensive literature searches of the following databases were performed: Cochrane Library, Pubmed, Web of Science, OVID, Elsevier ClinicalKey, Clinicaltrials.gov, and EMBASE. We searched for trials that compared cementless acetabular cups with screws or without screws, and were published in the English language. We evaluated the stability of the prosthesis by osteolysis and migration. The clinical scores included Harris hip scores (HHS) and pain scores. RESULTS: Nineteen articles involving 4046 THAs met the inclusion criteria. Our analysis revealed that additional screws did not increase the stability of acetabular cups, and there was no statistical significance between the groups with and without screws in osteolysis and clinically relevant migration. Revision rates showed no significant difference between the groups with and without screws. There was no difference in wear between the two groups. Our analysis showed no difference in pain scores and HHS between groups. CONCLUSION: Press-fit without screws could achieve sufficient acetabular cup stability. Acetabular cups without screws showed no difference from acetabular cups with screws in many outcomes. Additional screws are not required for cementless acetabular cups. LEVEL OF EVIDENCE: Level III.

circRNA expression pattern and ceRNA network in the pathogenesis of aseptic loosening after total hip arthroplasty.

Increasing evidence has demonstrated that circular RNA (circRNA) exerts important function in the pathogenesis of some diseases. While, the contributions of circRNAs to aseptic loosening after total hip arthroplasty (THA) remain largely unknown. Our research is to explore the differentially expressed circRNAs (DEcircRNAs) and elucidate complex regulated mechanism of circRNAs in aseptic loosening. The DEcircRNAs were identified by RNA sequencing (RNA-seq) analysis. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was adopted to corroborate these DEcircRNAs. The potential function of circRNAs in aseptic loosening tissue was identified by competing endogenous RNA (ceRNA) analysis. Enrichment analysis was performed for target mRNAs and host genes of the DEcircRNAs by Gene Oncology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). 257 DEcircRNAs were obtained from RNA-seq results. Following the RT-qPCR corroboration, 6 circRNAs (hsa_circ_0007482, hsa_circ_0005232, hsa_circ_0000994, hsa_circ_0000690, hsa_circ_0058092 and hsa_circ_0004496) were selected for further analysis. By circRNA-miRNA and miRNA-mRNA prediction, 6 circRNAs, 138 miRNAs and 1667 mRNAs were identified. Then, circRNA-miRNA-mRNA network was established. The result of GO and KEGG enrichment analysis suggested that the circRNAs were related with some biological functions and pathways of aseptic loosening. A novel pathogenesis and treatment strategy about aseptic loosening after THA was revealed from our study of circRNA-miRNA-mRNA network.

Primary Ewing's sarcoma of the vertebral body: A case report.

RATIONAL: The occurrence of Ewing's sarcoma in the vertebral body of elderly women is extremely rare, and the case of Ewing's sarcoma in the spine with secondary surgical repair after wrong diagnosis and treatment has not been reported. We report a case involving primary Ewing's sarcoma of the vertebral body in an elderly female. Owing to its rarity and controversial issues, we report a case report to discuss its clinical features, treatments, radiological, and histological characteristics. PATIENT CONCERNS: The elderly female patient came to see us with the manifestation of total paralysis of both lower limbs. The patient with a vertebral compression fracture as the primary manifestation was misdiagnosed in another hospital. The patient underwent inappropriate surgical treatment and was transferred to our hospital for diagnosis and second-stage surgery. DIAGNOSES: The postoperative pathological examination and immunohistochemical examination in our hospital confirmed: Ewing's sarcoma; Surgical history at other hospitals suggests: after Bone cement injection. INTERVENTIONS: The patient underwent a T6 and T8 laminectomy and T5/6-T9 pedicle screw fixation. OUTCOMES: Reexamination 1 month after the surgery showed that the tumor had been partially resected, the spinal cord compression was relieved, the tumor did not grow further, and the patient's lower limb physical ability, tactile sense, algesia and temperature sense recovered slightly. LESSONS: For patients with ewing's tumor in the spinal canal with symptoms of spinal cord compression, even if the patients with poor results after a unadvisable operation, it is still necessary to be actively in spinal cord compression by surgery. The differential diagnosis of Ewing's sarcoma and compression fractures is very important. For patients with vertebral tumors, special attention should be taken during vertebroplasty for bone cement leakage caused by excessive bone cement injection and increased local pressure. And some experience with imaging and laboratory findings.

The effect of Mg­2Zn­0.5Nd alloy on the mTOR signalling pathway in L6 cells.

Magnesium alloys have shown potential as biodegradable metallic materials for orthopaedic applications due to their degradability, and their resemblance to cortical bone and biocompatible degradation/corrosion products. However, the fast corrosion rate and the potential toxicity of their alloying element has limited the clinical application of Mg alloys. In the present study, a novel Mg­2Zn­0.5Nd alloy was prepared, and then the effects on the cell biological behaviour of the Mg­2Zn­0.5Nd alloy was compared with 317L stainless steel and titanium (Ti­6Al­4V) alloys as controls. The L6 cells were cultured in various leaching solutions. The proliferative effect of the Mg­2Zn­0.5Nd alloy was determined using the Cell Counting Kit­8 assay method on the L6 cells. Also, the regulation of key intracellular signalling proteins was investigated in the L6 cells by the western blot analysis. The Mg­2Zn­0.5Nd alloy showed no cytotoxicity and induced higher levels of proliferation in the myoblast cell line L6 than the other alloys. Molecular analysis demonstrated that Mg­2Zn­0.5Nd had stimulatory effects on bone morphogenetic protein­2 phosphorylation and on the activity of phosphorylated­mammalian target of the rapamycin (mTOR), protein kinase B and forkhead box protein O1. Mg­2Zn­0.5Nd also had no effect on P38 activity. These results suggested that Mg­2Zn­0.5Nd is likely to promote myoblast cell proliferation by activating the mTOR signalling pathway.

Genetic polymorphisms in MMP 2, 3 and 9 genes and the susceptibility of osteosarcoma in a Chinese Han population.

BACKGROUND: There are no data about the role of MMPs polymorphism in development of osteosarcoma. PATIENTS AND METHODS: Two-hundred fifty-one patients with osteosarcoma and 251 healthy controls were included to investigate the association between the MMP2, 3, 9 polymorphisms and the risk of osteosarcoma. RESULTS: Compared with the MMP2 SNP rs243865 homozygote CC, The heterozygous CT genotype was associated with significantly increased risk for osteosarcoma (OR = 1.86, 95% CI = 1.18-4.22, p = 0.014); the TT genotype was associated with increased risk for osteosarcoma (OR = 1.92, 95% CI = 1.21-3.52, p = 0.028). However, the genotype and allele frequencies of MMP3 rs3025058 and MMP9 rs3918242 polymorphisms were not significantly different. CONCLUSION: MMP2 rs243865 genotype was associated with increased risk for development of osteosarcoma in Chinese Han population.

Interleukin 10 gene -1082A/G polymorphism is associated with osteosarcoma risk and poor outcomes in the Chinese population.

Interleukin-10 (IL-10) is a multifunctional cytokine that participates in the development and progression of various malignant tumors. However, data regarding the role of IL-10 polymorphisms in osteosarcoma development are not available. A case-control study was conducted in 260 patients with osteosarcoma and 260 healthy controls to investigate the possible association between IL-10 polymorphisms and the risk of osteosarcoma. Our results indicate the IL-10 -1082A/G (rs1800896) polymorphism is significantly associated with an increased risk of osteosarcoma in all genetic models (AG vs. AA, odds ratio (OR) = 1.56; 95 % confidence interval (CI) = 1.28-2.32, P = 0.017; GG vs. AA, OR = 1.62, 95 % CI 1.24-2.61, P = 0.013; AG + GG vs. CC, OR = 1.76, 95 % CI = 1.31-3.01, P = 0.019). However, the genotype and allele frequencies of IL-10 -819C/T (rs1800871) and -592A/C (rs1800872) polymorphisms in osteosarcoma patients did not significantly differ from controls. Further analyses revealed that the IL-10 -1082A/G (rs1800896) genotypes were associated with advanced tumor stages and metastasis in osteosarcoma patients. Additionally, a statistically significant association between the IL-10 -1082A/G (rs1800896) genotype and poor survival in osteosarcoma patients was observed. Our results demonstrate that the IL-10 -1082A/G (rs1800896) genotype is associated with an increased susceptibility and worse outcome for osteosarcoma patients in the Chinese Han population.

Upregulation of cell proliferation via Shc and ERK1/2 MAPK signaling in SaOS-2 osteoblasts grown on magnesium alloy surface coating with tricalcium phosphate.

Magnesium (Mg) alloys have been demonstrated to be viable orthopedic implants because of mechanical and biocompatible properties similar to natural bone. In order to improve its osteogenic properties, a porous ß-tricalcium phosphate (ß-TCP) was coated on the Mg-3AI-1Zn alloy by alkali-heat treatment technique. The human bone-derived cells (SaOS-2) were cultured on (ß-TCP)-Mg-3AI-1Zn in vitro, and the osteoblast response, the morphology and the elements on this alloy surface were investigated. Also, the regulation of key intracellular signalling proteins was investigated in the SaOS-2 cells cultured on alloy surface. The results from scanning electron microscope and immunofluorescence staining demonstrated that (ß-TCP)-Mg-3AI-1Zn induced significant osteogenesis. SaOS-2 cell proliferation was improved by ß-TCP coating. Moreover, the (ß-TCP)-Mg-3AI-1Zn surface induced activation of key intracellular signalling proteins in SaOS-2 cells. We observed an enhanced activation of Src homology and collagen (Shc), a common point of integration between bone morphogenetic protein 2, and the Ras/mitogen-activated protein kinase (MAPK) pathway. ERK1/2 MAP kinase activation was also upregulated, suggesting a role in mediating osteoblastic cell interactions with biomaterials. The signalling pathway involving c-fos (member of the activated protein-1) was also shown to be upregulated in osteoblasts cultured on the (ß-TCP)-Mg-3AI-1Zn. These results suggest that ß-TCP coating may contribute to successful osteoblast function on Mg alloy surface. (ß-TCP)-Mg-3AI-1Zn may upregulate cell proliferation via Shc and ERK1/2 MAPK signaling in SaOS-2 osteoblasts grown on Mg alloy surface.

Cryotherapy on postoperative rehabilitation of joint arthroplasty.

PURPOSE: The effectiveness of cryotherapy on joint arthroplasty recovery remains controversial. This systematic review was conducted to assess the effectiveness of cryotherapy in patients after joint arthroplasty. METHODS: Comprehensive literature searches of several databases including Cochrane Library (2013), MEDLINE (1950-2013), and Embase (1980-2013) were performed. We sought randomised controlled trials that compared the experimental group received any form of cryotherapy with any control group after joint arthroplasty. The main outcomes were postoperative blood loss, adverse events, and pain. Analyses were performed with Revman 5.0. Results were shown as mean differences (MD) and standard deviations or as risk difference and 95 % confidence intervals (CIs). RESULTS: Ten trials comprised 660 total knee arthroplastys and three trials comprised 122 total hip arthroplastys (THAs) met the inclusion criteria. Blood loss was significantly decreased by cryotherapy (MD = -109.68; 95 % CI -210.92 to -8.44; P = 0.03). Cryotherapy did not increase the risk of adverse effect (n.s.). Cryotherapy decreased pain at the second day of postoperative (MD = -1.32; 95 % CI -2.37 to -0.27; P = 0.0003), but did not decreased pain at the first and third day of postoperative (n.s.). CONCLUSIONS: Cryotherapy appears effective in these selected patients after joint arthroplasty. The benefits of cryotherapy on blood loss after joint arthroplasty were obvious. However, the subgroup analysis indicated that cryotherapy did not decreased blood loss after THA. Cryotherapy did not increase the risk of adverse effect. Cryotherapy decreased pain at the second day of postoperative, but did not decreased pain at the first and third day of postoperative. LEVEL OF EVIDENCE: II.

Press-fit cementless acetabular fixation with and without screws.

PURPOSE: Cementless acetabular fixation for total hip arthroplasty (THA) is widely used. The question of using screws for a better primary and secondary acetabular fixation has been discussed in the literature in recent years. The aim of this meta-analysis was to compare fixation of acetabular cups with and without screws in total hip arthroplasty. METHODS: Electronic databases Embase, PubMed and Cochrane Library were used to search for randomised controlled trials reported through May 2013 of cementless acetabular fixation for THA with and without screws. Two independent reviewers assessed the trials for eligibility and quality. All related data matching our standards were abstracted for meta-analysis by RevMan 5.0. Evaluation criteria included revisions, migration and osteolysis. RESULTS: A total of 1,130 THAs enrolled into five trials were included in this meta-analysis. All studies compared fixation of acetabular cups with and without screws, and our pooled data showed no statistical significance between the two surgical methods in revision, migration and osteolysis. CONCLUSION: There is no significant difference between cementless acetabular fixation for THA with and without screws in revisions, migration or osteolysis.