Complex causal association between genetically predicted 731 immunocyte phenotype and osteonecrosis: a bidirectional two-sample Mendelian randomization analysis.

PURPOSE: Previous studies have explored the role of immune cells on osteonecrosis. This Mendelian randomization (MR) study further assessed 731 immunocyte phenotypes on osteonecrosis, whether a causal relationship exists, and provides some evidence of causality. METHODS: The 731 immunocyte phenotypes and osteonecrosis data used in this study were obtained from their respective genome-wide association studies (GWAS). The authors used inverse variable weighting (IVW) as the primary analysis method. In addition, the authors simultaneously employed multiple analytical methods, including MR-Egger, weighted mode, simple mode, and weighted median, to strengthen the final results. Finally, sensitivity analyses were conducted to verify the stability and feasibility of the data. RESULTS: The results of the IVW method of MR analysis showed that 8 immunocyte phenotypes were positively associated with osteonecrosis [ P <0.05, odds ratio (OR) > 1]; 18 immunocyte phenotypes were negatively associated with osteonecrosis ( P <0.05, OR<1), none of which were heterogeneous or horizontally pleiotropic ( P > 0.05) or reverse causality. In addition to this, in reverse MR, osteonecrosis was positively associated with 10 additional immunocyte phenotypes ( P <0.05, OR > 1) and negatively associated with 14 immunocyte phenotypes ( P <0.05, OR<1). And none of them had heterogeneity and horizontal pleiotropy ( P > 0.05) or reverse causality. CONCLUSIONS: The authors demonstrated a complex causal relationship between multiple immune phenotypes and osteonecrosis through a comprehensive two-way, two-sample MR analysis, highlighting the complex pattern of interactions between the immune system and osteonecrosis.

No evidence of genetic causality between diabetes and osteonecrosis: a bidirectional two-sample Mendelian randomization analysis.

OBJECTIVE: This study aimed to examine whether diabetes mellitus is causally associated with osteonecrosis. METHOD: Using publicly accessible genome-wide association study statistics, a bidirectional two-sample Mendelian randomization analysis was carried out. In order to determine whether diabetes has a causal effect on osteonecrosis and whether osteonecrosis has a causal effect on diabetes, we extracted six date on diabetes in Europeans from IEU OpenGWAS and GWAS Catalogue and osteonecrosis in Europeans from FinnGen. We then evaluated the data using inverse variance weighting, MR-Egger regression, weighted median, weighted mode, and simple mode. The results' stability and dependability were then evaluated using sensitivity analysis and heterogeneity analysis. Finally, meta-analysis is used to further confirm if there is a relationship between diabetes and osteonecrosis. RESULTS: When diabetes was used as an exposure factor, MR-Egger regression showed that directional fold product was unlikely to bias the results. Cochran's Q test showed only minor heterogeneity in a few data sets. Multidirectional tests Egger-intercept, MR-PRESSO and funnel plots for most data did not show multidirectional and asymmetry at the gene level. Most of the IVW results showed no causal relationship between diabetes mellitus and osteonecrosis. The results of meta-analysis of IVW methods further confirmed the absence of a causal relationship. Inverse MR analysis also showed no causal relationship between osteonecrosis and diabetes. CONCLUSION: Results of bidirectional MR analysis show no evidence of causal relationship between diabetes and osteonecrosis.

Silencing of LncRNA BDNF-AS attenuates Aß25-35-induced neurotoxicity in PC12 cells by suppressing cell apoptosis and oxidative stress.

OBJECTIVE: To explore the effects of long non-coding RNA (lncRNA) brain-derived neurotrophic factor anti-sense (BDNF-AS) on the Aß25-35-induced neurotoxicity in PC12 cells. METHODS: PC12 cells were induced by Aß25-35 to construct cell injury models of Alzheimer's disease (AD), and then transfected with siRNA-BDNF-AS. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to detect the expressions of BDNF-AS and BDNF. Besides, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Hoechst33342 staining were utilized to analyze the cell viability and apoptosis, respectively, Western blotting to evaluate the protein expressions, immunofluorescence to assess the Cytochrome C (Cyt C) release, and Rhodamine 123 (Rh123) to measure the mitochondrial membrane potential (MMP).The evaluation of oxidative stress was conducted via the determination of the levels of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT). RESULTS: Aß25-35 apparently increased BDNF-AS but decreased BDNF in PC12 cells, which also reduced viability and induced apoptosis of PC12 cells. Silencing of BDNF-AS could significantly up-regulate BDNF in Aß25-35-induced PC12 cells, with the elevated cell viability. Moreover, silencing BDNF-AS inhibited the apoptosis of Aß25-35-induced PC12 cells, suppressed the release of Cyt C, reduced the expression of cleaved caspase-3 and Bax, and lowered the mean fluorescence intensity (MFI) of Rh123, but it elevated the expression of Bcl-2. Besides, silencing BDNF-AS also reduced ROS intensity and MDA content, but enhanced the activities of SOD and CAT. CONCLUSION: Silencing BDNF-AS exerts protective functions to increase the viability, inhibit the apoptosis and oxidative stress of Aß25-35-induced PC12 cells by negative regulation of BDNF. ABBREVIATIONS: Aß25-35: amyloid beta peptide 25-35; AD: Alzheimer's disease; LncRNA BDNF-AS: long non-coding RNA brain-derived neurotrophic factor anti-sense; OS: Oxidative stress.

Prognostic Value of microRNA-224 in Various Cancers: A Meta-analysis.

BACKGROUND: During previous studies, microRNA-224 (miR-224) was frequently investigated and discovered to be of vital significance to prognosis of patients with various cancers. However, its accurate prognostic value has not been estimated worldwide. Herein, we performed meta-analysis to assess its potential predictive value in a variety of human tumors. METHODS: Qualified researches were identified up to March 1, 2017 through performing online searches in PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews. Overall survival (OS), disease-free survival (DFS) or progression-free survival (PFS) as a prognosis for various cancers were extracted and calculated, if available. Pooled hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Stata version 13.0 (StataCorp, College Station, Texas, USA). RESULTS: 22 eligible studies with 3000 patients were ultimately brought into the current meta-analysis. It suggested that high miR-224 expression was significantly associated with poor OS in tissue (HR = 1.43, 95% CI = 1.00-2.03). During multivariate analysis, high miR-224 expression was more significantly associated with OS in tissue (HR = 2.81, 95% CI = 1.91-4.13). Likewise, there were significant associations between tissue miR-224 expression and colorectal cancer (CRC), diffuse large B-cell lymphoma (DLBCL) and gastric cancer (GC) patients (p <0.05). Nevertheless, there were not significant associations between high tissue miR-224 expression and DFS (HR = 2.15, 95% CI = 0.97-4.79) or PFS (HR = 0.92, 95% CI = 0.53-1.59). CONCLUSION: As far as the present researches are concerned, tissue miR-224 has a significantly prognostic value in various cancers, especially in CRC, DLBCL and GC. Due to the complicated pathogenesis of cancers, more large-scale and standard researches are requisite.

Association of LPP and TAGAP Polymorphisms with Celiac Disease Risk: A Meta-Analysis.

Background: Lipoma preferred partner (LPP) and T-cell activation Rho GTPase activating protein (TAGAP) polymorphisms might influence the susceptibility to celiac disease. Therefore, we performed a meta-analysis by identifying relevant studies to estimate the risks of these polymorphisms on celiac disease. Methods: The PubMed, Web of Science and Embase databases were searched (up to October 2016) for LPP rs1464510 and TAGAP rs1738074 polymorphisms. Results: This meta-analysis included the same 7 studies for LPP rs1464510 and TAGAP rs1738074. The minor risk A allele at both rs1464510 and rs1738074 carried risks (odds ratios) of 1.26 (95% CI: 1.22-1.30) and 1.17 (95% CI: 1.14-1.21), respectively, which contributed to increased risks in all celiac disease patients by 10.72% and 6.59%, respectively. The estimated lambdas were 0.512 and 0.496, respectively, suggesting that a co-dominant model would be suitable for both gene effects. Conclusions: This meta-analysis provides robust estimates that polymorphisms in LPP and TAGAP genes are potential risk factors for celiac disease in European and American. Prospective studies and more genome-wide association studies (GWAS) are needed to confirm these findings, and some corresponding molecular biology experiments should be carried out to clarify the pathogenic mechanisms of celiac disease.

Prognostic value of microRNAs in hepatocellular carcinoma: a meta-analysis.

BACKGROUND: Numerous articles reported that dysregulated expression levels of miRNAs correlated with survival time of HCC patients. However, there has not been a comprehensive meta-analysis to evaluate the accurate prognostic value of miRNAs in HCC. DESIGN: Meta-analysis. MATERIALS AND METHODS: Studies, published in English, estimating expression levels of miRNAs with any survival curves in HCC were identified up until 15 April, 2017 by performing online searches in PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews by two independent authors. The pooled hazard ratios (HR) with 95% confidence intervals (CI) were used to estimate the correlation between miRNA expression and overall survival (OS). RESULTS: 54 relevant articles about 16 miRNAs, with 6464 patients, were ultimately included. HCC patients with high expression of tissue miR-9 (HR = 2.35, 95% CI = 1.46-3.76), miR-21 (HR = 1.76, 95% CI = 1.29-2.41), miR-34c (HR = 1.64, 95% CI = 1.05-2.57), miR-155 (HR = 2.84, 95% CI = 1.46-5.51), miR-221 (HR = 1.76, 95% CI = 1.02-3.04) or low expression of tissue miR-22 (HR = 2.29, 95% CI = 1.63-3.21), miR-29c (HR = 1.35, 95% CI = 1.10-1.65), miR-34a (HR = 1.84, 95% CI = 1.30-2.59), miR-199a (HR = 2.78, 95% CI = 1.89-4.08), miR-200a (HR = 2.64, 95% CI = 1.86-3.77), miR-203 (HR = 2.20, 95% CI = 1.61-3.00) have significantly poor OS (P < 0.05). Likewise, HCC patients with high expression of blood miR-21 (HR = 1.73, 95% CI = 1.07-2.80), miR-192 (HR = 2.42, 95% CI = 1.15-5.10), miR-224 (HR = 1.56, 95% CI = 1.14-2.12) or low expression of blood miR-148a (HR = 2.26, 95% CI = 1.11-4.59) have significantly short OS (P < 0.05). CONCLUSIONS: In conclusion, tissue miR-9, miR-21, miR-22, miR-29c, miR-34a, miR-34c, miR-155, miR-199a, miR-200a, miR-203, miR-221 and blood miR-21, miR-148a, miR-192, miR-224 demonstrate significantly prognostic value. Among them, tissue miR-9, miR-22, miR-155, miR-199a, miR-200a, miR-203 and blood miR-148a, miR-192 are potential prognostic candidates for predicting OS in HCC.