CXCL8 promotes the invasion of human osteosarcoma cells by regulation of PI3K/Akt signaling pathway.

Chemokine cysteine-X-cysteine motif ligand 8 (CXCL8) is up-regulated in many malignancies, indicating that CXCL8 takes part in tumor progression. However, the expression and function of CXCL8 in osteosarcoma remained not fully elucidated. In this study, expressions of 12 cytokines and chemokines were measured in the serum from 12 of normal controls (NCs) and 25 of osteosarcoma patients. The human osteosarcoma cell line MG-63 was stimulated by recombinant CXCL8 to further analyze invasion, proliferation, apoptosis, cell cycles, cytokine secretions, and signaling pathways. We found that serum concentrations of CXCL8 and vascular endothelial growth factor were elevated in osteosarcoma patients in comparison with those in NCs. CXCL8 stimulation led to enhancement of invasion and suppression of late stage apoptosis in MG-63 cells. Moreover, secretions of MMPs by MG-63 cells were also increased upon stimulation. However, early stage apoptosis, proliferation, and cell cycles were not affected by CXCL8 treatment. Furthermore, CXCL8 stimulation induced elevations of phosphorylated PI3K and Akt, but not PKC or FAK. In conclusion, our findings suggested that CXCL8 enhanced the invasion and suppressed late stage apoptosis of osteosarcoma cells probably via influencing PI3K/Akt signaling pathway and elevating the expression of MMPs. CXCL8 may promote disease progression of osteosarcoma as a protumorigenic molecule, and may be served as a new therapeutic target for osteosarcoma.

Identification of key genes associated with Schmid-type metaphyseal chondrodysplasia based on microarray data.

This study aimed to gain a better understanding of the molecular circuitry of Schmid-type metaphyseal chondrodysplasia (SMCD), and to identify more potential genes associated with the pathogenesis of SMCD. Microarray data from GSE72261 were downloaded from the NCBI GEO database, including collagen X p.Asn617Lys knock-in mutation (ColXN617K), ablated XBP1 activity (Xbp1CartΔEx2), compound mutant (C/X), and wild-type (WT) specimens. Differentially expressed genes (DEGs) were screened in Xbp1 vs. WT, Col vs. WT and CX vs. WT, respectively. Pathway enrichment analysis of these DEGs was performed. Transcription factors (TFs) of the overlapping DEGs were identified. Weighted correlation network analysis (WGCNA) was performed to find modules of DEGs with high correlations, followed by gene function analysis and a protein-protein interaction network construction. In total, 481, 1,530 and 1,214 DEGs were identified in Xbp1 vs. WT, Col vs. WT and CX vs. WT, respectively. These DEGs were enriched in different pathways, such as extracellular matrix (ECM)-receptor interaction and metabolism-related pathways. A total of 7 TFs were found to regulate 19 common upregulated genes, and 4 TFs were identified to regulate 21 common downregulated genes. Two significant gene co-expression modules were enriched and DEGs in the 2 modules were mainly enriched in different biological processes, such as ribosome biogenesis. Moreover, Kras (downregulated), Col5a1 (upregulated) and Furin (upregulated) were both identified in the regulatory networks and protein-protein interaction (PPI) network. On the whole, our findings indicate that the Kras, Col5a1 and Furin genes may play essential roles in the molecular mechanisms of SMCD, which warrants further investigation.

A case report of children's divergent dislocation of the elbow and review of literature.

BACKGROUND: The divergent dislocation of the elbow is not common in children, and the imaging is difficult and challenging. This often leads to misdiagnosis or inappropriate treatment. The literature has reported a total of 19 cases currently. METHODS: A 10-year-old girl with divergent dislocation of the elbow was admitted in our department in November 2013. When playing basketball, her right elbow was injured on the concrete floor. After injury, her right elbow joint became severely swollen, with obvious deformity. The anteroposterior X-ray of elbow showed right olecranon and coronoid fractures, the proximal radioulnar separation, and displacement; the lateral X-ray showed the posterior dislocation of right elbow. RESULTS: Under local anesthesia, right elbow manual reduction was performed, and after reduction, 3-dimensional computed tomography reconstruction displayed good reduction of the elbow dislocation. The fracture of coronoid displaced minimally, but the olecranon fracture showed great displacement which underwent the open reduction and internal fixation. Postoperatively, a plaster splint was applied for protection, with regular outpatient follow-ups. At the end of the normal follow-up, the active ROM of the right elbow joint was 5° to 130° and with normal rotation. CONCLUSION: Therefore, through the treatment of this case and the literature review, we believe that for children, most divergent dislocations of the elbow may achieve a better clinical result with closed reduction, and we also believe that after surgery or closed reduction, in the follow-up, proper function exercise is an important condition for the rehabilitation of children. For such patients, correct diagnosis and timely treatment can help to avoid joint dysfunction of elbow.

PFKFB3 modulates glycolytic metabolism and alleviates endoplasmic reticulum stress in human osteoarthritis cartilage.

Glycolytic disorder has been demonstrated to be a major cause of osteoarthritis (OA) and chondrocyte dysfunction. The present work aimed to investigate the expression and role of the glycolytic regulator 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) in OA cartilage. It was found that PFKFB3 expression was down-regulated in human OA cartilage tissues and in tumour necrosis factor (TNF)-α- or interleukin (IL)-1ß-stimulated human chondrocytes. The glycolytic metabolism appeared as glucose utilization and adenosine triphosphate (ATP) generation, and lactate production was stunted in OA cartilage. However, the impaired glycolytic process in OA cartilage was improved by PFKFB3 overexpression, which was confirmed in TNF-α- or IL-1ß-treated chondrocytes. Furthermore, the expressions of endoplasmic reticulum (ER) stress-associated genes including PERK, ATF3, IRE1, phosphorylated eIF2α (p-eIF2α) and MMP13 were enhanced in OA cartilage explants, while they were decreased by AdPFKFB3 transfection. PFKFB3 also modulated the expressions of PERK, ATF3, IRE1, p-eIF2α and MMP13 in tunicamycin-exposed chondrocytes. Additionally, PFKFB3 improved the cell viability of OA cartilage explants and chondrocytes through the PI3K/Akt/C/EBP homologous protein (CHOP) signalling pathway. The transfection of AdPFKFB3 also significantly reduced caspase 3 activation and promoted aggrecan and type II collagen expressions in OA cartilage explants and chondrocytes. In all, this study characterizes a novel role of PFKFB3 in glycolytic metabolism and ER stress of OA cartilage explants and chondrocytes. The study might provide a potential target for OA prevention or therapy.

MicroRNA-9 regulates osteoblast differentiation and angiogenesis via the AMPK signaling pathway.

MiR-9 has been found to be involved in the repair of spinal cord injury and regulates the proliferation and differentiation of mesenchymal stem cells. However, the role of miR-9 in repair of bone defects has not been well studied. The current study was designed to investigate its role and potential underlying mechanism in regulating osteoblast differentiation and angiogenesis. After treating the murine pre-osteoblast cell line MC3T3-E1 with BMP2, miR-9 expression was obviously down-regulated. Following transfection with miR-9 mimics, its overexpression enhanced the differentiation of MC3T3-E1 cells into osteoblasts as evidence that miR-9 up-regulated the mRNA levels of osteoblast differentiation-related protein, as well as increased differentiation and mineralization of osteoblasts. Further functional analysis has shown that miR-9 overexpression effectively increased human umbilical vein endothelial cell proliferation. Moreover, miR-9 up-regulation promoted cell migration, VEGF, and VE-cadherin concentrations, as well as tube formation in vitro. The mechanistic assay demonstrated that overexpression of miR-9-induced activation of the AMPK signaling pathway. Taken together, our findings suggested that miR-9 overexpression promoted osteoblast differentiation and angiogenesis via the AMPK signaling pathway, representing a novel and potential therapeutic target for the treatment of bone injury-related diseases.

Fracture of the Lateral Process of the Talus in Children: A Kind of Ankle Injury With Frequently Missed Diagnosis.

OBJECTIVE: To analyze the clinical characteristics, the treatment, and the outcome of lateral process fracture of the talus in children. METHODS: From March 2011 to October 2013, 12 children with lateral process fracture of the talus were treated in our hospital. The study contained 3 female and 9 male patients, including 8 patients affected on the left side and 4 on the right side. The age at the time of injury ranged from 8 to 13 years. Concomitant injuries included undisplaced calcaneus fractures in 1 case and distal fibula epiphysis injury in 1 case. The patients presented to our hospital from 2 hours to 2 months after injury. All cases were classified by the Hawkins fracture system. Treatment included immobilization and not bearing weight for 4 weeks for nondisplaced fractures or open reduction and fixation for significantly displaced fractures. Therapeutic effects were evaluated on the basis of the AOFAS (The American Orthopaedic Foot and Ankle Society) Ankle Hindfoot Scale. RESULTS: Seven of the cases were initially diagnosed in our department, and the diagnosis was missed in 5 cases. The missed diagnosis rate was 42%. All patients were followed up for 18 months on an average. Follow-up radiographs did not show avascular necrosis of the talus, nonunion, and malunion in any patient. The mean AOFAS hindfoot score was 96 points. The clinical result was found to be excellent in 10 patients, good in 1 patient, and fair in 1 patient (the success rate was 92%). CONCLUSIONS: The lateral process of talus fracture is a frequently missed injury. The diagnosis must rely on thorough check-ups combined with standard radiographs and computed tomographic scan. Depending on the type and the displacement of the fracture, proper treatment options could be implemented for desirable clinical effects.

Comparative study of serum proteomes in Legg-Calve-Perthes disease.

BACKGROUND: Legg-Calve-Perthes Disease (LCPD) is an idiopathic osteonecrosis of the developing femoral head complicated by pain and disability of the hip joint. To date, the pathological mechanisms of LCPD are not well-known. This study screened the changes in serum protein expression in patients with LCPD. METHODS: Age- and sex-matched serum samples from 10 control subjects and 10 patients with LCPD were compared using the isobaric tags for relative and absolute quantification (iTRAQ) technique. Gene ontology analyses, KEGG pathway and functional network analyses were performed. Proteins of interest with large differences in expression, S100-A8, alpha-1-acid glycoprotein 1, haptoglobin and apolipoprotein E, were compared by western blotting. RESULTS: The disease/control ratios showed 26 proteins were significantly differentially expressed (all p < 0.05). Including higher abundances of complement factor H (1.44), complement C4-B (1.45), isocitrate dehydrogenase [NAD] subunit alpha (2.7) alpha-1-acid glycoprotein 1 (1.87), heptoglobin (1.53) and Ig lambda-2 chain C regions (1.46), and lower levels of apolipoprotein E (0.50), apolipoprotein F (0.60), apolipoprotein C-III (0.69), S100-A8 (0.73), S100-A9 (0.75) and prothrombin (0.77) in LCPD than in controls. The alpha-1-acid glycoprotein 1 and haptoglobin increases, and apolipoprotein E and S100-A8 decreases were confirmed by western blot. KEGG pathway analysis revealed these proteins were related to the complement and coagulation cascades, Staphylococcus aureus infection, PPAR signaling, fat digestion and absorption, and vitamin digestion and absorption. Functional network analysis suggested that the proteins were involved in lipid regulation. CONCLUSIONS: The complement and coagulation cascades, and abnormal lipid metabolism may be involved in the pathogenesis of LCPD.

Ulnar Rotation Osteotomy for Congenital Radial Head Dislocation.

PURPOSE: To evaluate an ulnar rotation osteotomy for congenital anterior dislocation of the radial head. METHODS: Nine patients (5 boys and 4 girls aged 6 to 13 years) with congenital anterior dislocation of the radial head were treated with ulnar rotation osteotomy. Magnetic resonance imaging of the elbow showed the proximal radioulnar joint on the anterior-lateral side of the ulna rather than on the lateral side in patients with congenital anterior dislocation of the radial head. On the basis of this finding, we performed an osteotomy on the ulna and laterally rotated the proximal radioulnar joint achieving radial head reduction and restoring the anatomical relationship between the radial head and the capitellum. Clinical and radiographical evaluation of the elbow was performed before surgery and at postoperative follow-up. RESULTS: All patients were followed for 13 to 45 months after surgery. Elbow radiography showed that the radiocapitellar joint was reduced in all patients at the last follow-up visit and that the carrying angle was decreased relative to that in the preoperative condition. Elbow stability and the range of elbow flexion motion were improved at the last follow-up. We did not observe ulnar osteotomy site nonunion or elbow osteoarthritis in these patients. Furthermore, radial head dislocation did not recur. CONCLUSIONS: At early follow-up, ulnar rotation osteotomy was a safe and effective method for the treatment of congenital anterior dislocation of the radial head. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Valgus Osteotomy of the Proximal Humerus to Treat Humerus Varus in Children.

PURPOSE: Humerus varus is a rare disease in children that can cause limited active abduction and forward flexion of the shoulder as well as upper limb length discrepancies. Valgus osteotomy of the proximal humerus is an effective method to treat this disease, although internal fixation with a plate and screws is rarely reported. The purpose of this article is to investigate the clinical outcome and radiographic changes of valgus osteotomy of the proximal humerus through internal fixation with a plate and screws. METHODS: From April 2005 to August 2011, our group treated 5 patients including 1 girl and 4 boys. The left side was the affected side in all cases. The mean operation age was 13 years. We performed valgus osteotomy of the proximal humerus with internal fixation provided by a plate and screws to treat these patients. Follow-ups were performed with an average of 35.6 months (range, 24 to 74 mo). The changes in postoperative shoulder function and radiographic images were analyzed. RESULTS: The actual cause of the humerus varus was not clear. Abduction and forward flexion of the shoulder were significantly increased in all patients. However, there was no obvious improvement in upper limb length. The postoperative humeral neck-shaft angle improved notably as well. We used a paired t test for statistical treatment. The P value was 0.001. No bony nonunion or delayed union was observed. The time required for union was 3 to 6 months. No obvious complications occurred. CONCLUSIONS: Valgus osteotomy of the proximal humerus using a plate-screw fixation method can correct the deformity and provide strong fixation in children. The postoperative improvement of shoulder motion and radiologic changes were satisfactory. However, we need to do second operation to remove the plate. Meanwhile, the patients would require a second operation to elongate the affected limb.

[Three-dimensional CT imaging in the treatment of children's developmental dislocation of hip].

OBJECTIVE: To investigate the value of 3-dimensional CT in the treatment of developmental dislocation of hip (DDH). METHODS: From 2003.6 to 2007.6, the femoral neck anteversion (FNA) and morphology of acetebulum in 53 patients with DDH (61 hips) were studied by three-dimensional CT imaging. Among the patients, 12 patients were male and 41 patients were female, ranging in age from 3 to 16 years (mean 5.6 years). Thirty-four patients had dislocation in left hip joint, 11 patients had dislocation in right hip joints, and 8 patients had double dislocations. The patients were treated with Pemberton or Chiari acetabuloplasty and femoral osteotomy. After operation all the cases were obeserved by 3-dimensional CT again. The femoral neck anteversions were measured and the shapes of new acetabulum were observed. RESULTS: Among 61 hips of DDH, the maximum femoral neck anteversion was 90 degrees. The minimum was 35 degrees and the average was (45.6 +/- 11.4) degrees. Among 45 normal hips, the average femoral neck anteversion was (23.5 +/- 10. 2) degrees. The acetabulum were dysplastic according with what were found in the operation. After operation the femoral neck anteversions decreased and averaged (15.6 +/- 5.8) degrees. The femoral head containment improved. CONCLUSION: The advantages of 3D CT scan includes manifestation of acetebular morphology, correct measurement of femoral neck anteversion and evaluation of operative procedure and efficacy. The 3-dimensional CT method is deserved to use widely in the treatment of developmental dislocation of hip in children.