Osteosarcoma (OS) is the most common primary bone tumor, whose poor prognosis is mainly due to lung metastasis. The aim of this study is to build a practical and valid diagnostic test that can predict the risk of OS metastasis and progression. We performed weighted gene co-expression network analysis (WGCNA) on GSE21257 from the Gene Expression Omnibus (GEO) database, which contains microarray data of biopsies from OS patients. In these modules, the highest association was found between the blue module and metastasis stage (r = -0.52) by Pearson's correlation analysis. Based on Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression, we derived eight clinically significant genes and constructed an eight-gene signature for metastasis status. It showed great efficacy to distinguish metastasis from non-metastasis (AUC = 0.886) and the results were validated in The Cancer Genome Atlas (TCGA) database. Functional enrichment analysis of hub genes showed that their biological processes focused on immune-related pathways, suggesting the important roles of immune cells, immune pathways and the tumor microenvironment in metastasis development. In conclusion, we discovered an efficient gene signature with great efficacy to distinguish metastasis status, which may help improve early diagnosis and treatment, enhancing the clinical outcomes of OS patients. Besides we created an effective protocol to seek for several hub genes in high-throughput data by combining WGCNA and LASSO Cox regression.

A growing number of children and adolescents are being diagnosed as Chiari malformation type I (CM-I) for behavioral disorders, developmental delay, seizures, or abnormal orpharyngeal function. The aim of this study was to compare the clinical characteristics, imaging findings and surgical outcomes of CM-I in pediatric and adult patients. Between January 2014 and June 2017, 84 patients with CM-I underwent surgical treatment in our department. We divided the patients into two groups: pediatric group (n=11, age <18 years) and adult group (n=73, age ≥18 years). Data on clinical characteristics, imaging findings, surgical outcomes, and prognosis were retrospectively reviewed and compared between these two groups. For clinical presentation, scoliosis (36.4%) and developmental delay (36.4%) were more common in pediatric patients, whereas, sensory disturbance (58.9%) and motor weakness (41.1%) were more common in adult patients. Imaging findings showed that the incidence of hydrocephalus and craniovertebral junctional abnormalities was significantly higher in pediatric group than in adult group (P<0.05). Compared to adult group, pediatric group showed a better improvement or resolution of syrinx and tonsillar herniation after surgical treatments (P<0.05). The total Chicago Chiari Outcome Scale (CCOS) score in pediatric patients at the last followup was significantly higher than that in adult patients (P=0.002). In conclusion, the clinical characteristics and imaging findings appeared to be different in pediatric and adult patients with CM-I. The surgical outcomes of pediatric patients were shown to be significantly better than those of adult patients.

◥Bone metastasis is a severe complication associated with various carcinomas. It causes debilitating pain and pathologic fractures and dramatically impairs patients' quality of life. Drugs aimed at osteoclast formation significantly reduce the incidence of skeletal complications and are currently the standard treatment for patients with bone metastases. Here, we reported that serum-and glucocorticoid-inducible kinase 1 (SGK1) plays a pivotal role in the formation and function of osteoclasts by regulating the Ca 2þ release-activated Ca 2þ channel Orai1. We showed that SGK1 inhibition represses osteoclastogenesis in vitro and prevents bone loss in vivo. Furthermore, we validated the effect of SGK1 on bone metastasis by using an intracardiac injection model in mice. Inhibition of SGK1 resulted in a significant reduction in bone metastasis. Subsequently, the Oncomine and the OncoLnc database were employed to verify the differential expression and the association with clinical outcome of SGK1 gene in patients with breast cancer. Our data mechanistically demonstrated the regulation of the SGK1 in the process of osteoclastogenesis and revealed SGK1 as a valuable target for curing bone metastasis diseases. Materials and Methods ReagentsGSK650394 and BTP2 was purchased from Sigma-Aldrich. Soluble recombinant human M-CSF and mouse RANKL were obtained from PeproTech.