Development and validation of an oxidative stress­related prognostic signature in osteosarcoma: A combination of molecular experiments and bioinformatics.

Osteosarcoma (OS) is one of the most prevalent malignancies with a bad prognosis. Oxidative stress is closely associated with various type of cancer. The present study aimed to establish an oxidative stress-related gene prognostic signature. Supported by The Cancer Genome Atlas and Gene Expression Omnibus, the least absolute shrinkage and selection operator regression, Cox regression, receiver operating characteristic curves and Kaplan-Meier survival analysis were used to construct and validate a prognostic signature and the derived risk score. Tumor microenvironment scores and immune infiltration levels in OS were calculated. Correlation between these parameters and risk score was analyzed. In addition, single analysis of each hub gene was performed. Finally, a series of molecular experiments was used to detect the role of MAP3K5 (one of the hub genes) in OS. A total of five genes most associated with OS prognosis were identified as independent predictors, namely catalase (CAT), mitogen-activated protein kinase 1 (MAPK1), glucose-6-phosphate dehydrogenase (G6PD), mitogen-activated protein kinase kinase kinase 5 (MAP3K5) and C-C motif chemokine ligand 2 (CCL2). Based on the signature, higher risk score indicated poorer prognosis. Nomogram performed well and reliably predicted 3- and 5-year survival rate in OS. Patients with increasing risk scores had higher tumor purity and lower immune infiltration levels. Compared with an osteoblast cell line, the expression of CAT, CCL2, MAPK1 and G6PD was upregulated and MAP3K5 was downregulated. MAP3K5 inhibited cellular proliferation and motility, promoted cellular apoptosis and induced reactive oxygen species generation. Overall, the signature could effectively predict the prognosis of patients with OS and were expected to be potential biomarkers. And it provided new ideas for understanding the interactions between oxidative stress and OS.

Influence of Genotypic and Environmental Factors on Tobacco Leaves Based on Metabolomics.

Environmental factors affect plant metabolites, different climates, cultivation conditions, and biotic stresses and genotypes strongly affect their chemical composition and contents. Our aim is to examine the environmental and genetic interaction effects on tobacco metabolite composition. UPLC-QTOF MS/MS coupled with multivariate data analyses were applied for the metabolomics analysis of three tobacco cultivars from different planting regions in China. Principal component analysis (PCA) revealed that environmental factors have a greater effect on tobacco metabolism compared to genotypes. Twelve biomarkers were screened by orthogonal partial least squares discrimination analysis (OPLS-DA). Univariate analysis indicated that Malate, conjugated chlorogenic acid, chlorogenic acid, quercetin 3-rutinoside-7-glucoside, and unknown compound 5 were only influenced by environmental factors (independent of genotype). Quinate, neochlorogenic acid, and ouabagenin, taxezopidine K1, taxezopidine K2, and taxezopidine K3 in tobacco were influenced by the interaction of environmental factors and the genotype. Our results suggest that metabolomics based on UPLC-QTOF MS/MS could be used to analyze the ecological functions of biomarker metabolites and understand the mechanisms of plant adaption to the environment.

3D-printed brace in the treatment of adolescent idiopathic scoliosis: a study protocol of a prospective randomised controlled trial.

INTRODUCTION: Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of the spine. Brace treatment is effective for eligible patients with AIS and the effectiveness is significantly correlated with the average brace-wear time per day. Three-dimensional (3D) printing technology is a recent advancement that offers unique opportunities for biomedical applications, and customisation of scoliosis braces might lead to greater patient satisfaction and improved compliance. We present here the design of a randomised controlled trial on the clinical effectiveness of 3D-printed braces versus thoracolumbosacral orthoses (TLSO) for patients with AIS. METHODS AND ANALYSIS: Patients with AIS (age 10-16 years) with Risser sign 0-II, Cobb angle of main curve of 20°-40°, premenarchal or no more than 1-year postmenarchal (for women), and no history of treatment are eligible, unless they are unable to tolerate the treatment or refuse participation. A total of 88 patients will be randomised into either the 3D group or TLSO group on a 1:1 basis. Participants in the 3D group will choose between a 3D-printed brace and TLSO, according to the Zelen's design of the trial. Primary outcome measures will include the average brace-wear time per day, health-related quality of life and Cobb angle progression of the primary curve. Secondary outcome measures will include immediate in-brace correction of Cobb angle of the primary curve, rate of conversion to surgery and incidence of any adverse events. This study is designed as a single-centre, two-arm, superiority and open-label randomised controlled trial. The sample size is calculated with reference to the preliminary study and based on the sample size calculation formula. ETHICS AND DISSEMINATION: This study was approved by the Peking University Third Hospital Medicine Science Research Ethics Committee (No: 2019-017-02). Results of the trial will be submitted for publication in a peer-reviewed journal and as conference presentations. TRIAL REGISTRATION NUMBER: ChiCTR1900027379, pre-results.

The efficacy and potential mechanism of cnidium lactone to inhibit osteoclast differentiation.

Cnidium lactone is effective in the maintenance of bone mass in various osteoporosis models; however, the precise molecular mechanisms are not understood. In this study, we investigated the effects and underlying mechanisms of action of cnidium lactone on receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis. Cnidium lactone dose-dependently inhibited osteoclast differentiation and formation, decreased the bone-resorbing activity of osteoclasts, and downregulated the expression of osteoclast differentiation marker genes. Cnidium lactone treatment considerably reduced RANKL-induced p38 MAPK and PI3K-Akt signal activity in RAW264.7 cells. The cnidium lactone-induced osteoclastogenesis was significantly attenuated by inhibition of p38 and PI3K through pretreatment with SB203580 and LY294002, respectively. Furthermore, cnidium lactone inhibited the expression of c-Fos and NFATc-1 with dose-dependently and enhanced by SB203580 and LY294002. In conclusion, cnidium lactone inhibits osteoclast differentiation through p38 MAPK and PI3K-Akt signalling pathway/c-Fos/NFATc1 signalling pathway.