Identification and Verification of a Glycolysis-Related lncRNA Prognostic Signature for Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a primary liver cancer with a high mortality rate. The search for a new biomarker could help the prognosis of HCC patients. We identified the glycolytic gene set associated with HCC and the glycolytic lncRNA based on TCGA and MsigDB databases. According to these lncRNAs, K-means clustering, and regression analysis were performed on the patients. Two groups of HCC patients with different lncRNA expression levels were obtained based on K-means clustering results. The results of difference analysis and enrichment analysis showed that DEmRNA in the two HCC populations with significant survival differences was mainly enriched in transmembrane transporter complex, RNA polymerase II specificity, cAMP signaling pathway, and calcium signaling pathway. In addition, a prognostic model of HCC with 4 DElncRNAs was constructed based on regression analysis. ROC curve analysis showed that the model had good predictive performance. Drug predictionresults showed that the efficacy of JQ1, niraparib, and teniposide was higher in the low-risk group than in the high-risk group. In conclusion, this study preliminarily identified glycolytic-related prognostic features of lncRNAs in HCC and constructed a risk assessment model. The results of this study are expected to guide the prognosis assessment of clinical HCC patients.

Abnormally Expressed Circular RNAs are Promising Biomarkers for Diagnosis of Hepatocellular Carcinoma: a Meta-Analysis.

BACKGROUND: Circular RNAs (circRNAs), which are expressed aberrantly in tissues and body fluids in individuals with hepatocellular carcinoma (HCC), may serve as promising biomarkers for diagnosis of HCC. We performed a meta-analysis of the overall diagnostic performance of circRNAs for diagnosis of HCC. METHODS: PubMed, Web of Science, EMBASE, and Chinese National Knowledge Infrastructure (CNKI) were searched for eligible studies. The quality of all included literature was evaluated using the Quality Assessment for Studies of Diagnostic Accuracy 2 (QUADAS-2) checklist. Statistical analyses were conducted using STATA 12.0 and Meta-Disc 1.4 software. RESULTS: A total of 6 studies, 2 of which identified up-regulated circRNAs and 4 of which identified down-regulated circRNAs, were included in the meta-analysis. The pooled sensitivity, specificity, and area under the curve (AUC) were 0.75 (95% confidence interval (CI): 0.71 - 0.78), 0.82 (95% CI: 0.78 - 0.85), and 0.90, respectively. Stratified analyses showed that the diagnostic efficacy of down-regulated circRNAs for diagnosis of HCC was inferior to that of up-regulated circRNAs (sensitivity: 0.69 vs. 0.91; specificity: 0.78 vs. 0.94; diagnostic odds ratio (DOR): 9.12 vs. 128.97; AUC: 0.83 vs. 0.99). CONCLUSIONS: Abnormally expressed circRNAs may be diagnostic indicators of HCC. Additional studies are needed to confirm whether circRNAs are diagnostic biomarkers of HCC.

Abnormally Expressed Long Non-Coding RNAs in Nasopharyngeal Carcinoma: a Meta-Analysis.

BACKGROUND: Dysregulated long non-coding RNAs (lncRNAs) have been extensively explored in nasopharyngeal carcinoma (NPC) research. The current study focused on elucidating the overall diagnostic and prognostic performances of abnormally expressed lncRNAs in NPC. METHODS: We performed a systematic literature search based on the online databases. The pooled effects sizes for diagnosis and prognosis were synthesized using a fixed or random effect model. Hazard ratios (HRs) with 95% confidence intervals (CIs) for primary endpoints of overall survival (OS) and disease-free survival (DFS) were aggregated. Effects of publication bias on overall pooled accuracy were assessed via trim and fill adjustment method. RESULTS: Thirteen studies comprising 580 cases for diagnosis and 1,400 for prognosis were included. The results showed that abnormally expressed lncRNAs could distinguish NPC from non-cancerous individuals with a pooled sensitivity of 0.65 (95% CI: 0.63 - 0.68), specificity of 0.83 (95% CI: 0.80 - 0.86), and AUC (area under the curve) of 0.79. For prognosis, abnormally expressed lncRNAs (high vs. low) were associated with worse survival times in both OS (HR = 2.88, 95% CI: 1.97 - 4.21, p = 0.000) and DFS (HR = 2.13, 95% CI: 1.56 - 2.90, p = 0.000) in NPC patients. Moreover, stratified analyses manifested that lncRNA transcription level was markedly correlated with TNM classification, clinical stage, and distant metastasis. CONCLUSIONS: Our data evidence that abnormally expressed lncRNAs may be rated as promising biomarkers or indicators for cancer diagnosis and prognosis in NPC.

Glucocorticoid-induced S-adenosylmethionine enhances the interferon signaling pathway by restoring STAT1 protein methylation in hepatitis B virus-infected cells.

Patients with chronic hepatitis B usually exhibit a low response to treatment with interferon α (IFN-α). An alternative approach to increase the response rate of IFN-α might be to immunologically stimulate the host with glucocorticoids (GCs) before treatment with IFN-α, but the underlying mechanism remains unclear. We hypothesized that the GCs enhance IFN signaling by inducing S-adenosylmethionine (AdoMet) when hepatitis B virus (HBV) replication was effectively suppressed by IFN-α. Here, we investigated the effect of GCs and IFN-α on AdoMet production and methionine adenosyltransferase 1A (MAT1A) expression in vitro. Furthermore, we determined whether post-transcriptional regulation is involved in HBV-repressed MAT1A expression and AdoMet production induced by dexamethasone (Dex). We found that AdoMet homeostasis was disrupted by Dex and that Dex directly regulated MAT1A expression by enhancing the binding of the glucocorticoid receptor (GR) to the glucocorticoid-response element (GRE) of the MAT1A promoter. HBV reduced AdoMet production by increasing methylation at GRE sites within the MAT1A promoter. The X protein of hepatitis B virus led to hypermethylation in the MAT1A promoter by recruiting DNA methyltransferase 1, and it inhibited GR binding to the GRE in the MAT1A promoter. Dex could increase an antiviral effect by inducing AdoMet production via a positive feedback loop when HBV is effectively suppressed by IFN-α, and the mechanism that involves Dex-induced AdoMet could increase STAT1 methylation rather than STAT1 phosphorylation. These findings provide a possible mechanism by which GC-induced AdoMet enhances the antiviral activity of IFN-α by restoring STAT1 methylation in HBV-infected cells.

Association Between TP53 Gene Codon 72 Polymorphism and Acute Myeloid Leukemia Susceptibility: Evidence Based on a Meta-Analysis.

BACKGROUND: Many studies have reported that the p53 codon 72 polymorphism is associated with acute myeloid leukemia (AML) susceptibility; however, the conclusions are inconsistent. Therefore, we performed this meta-analysis to obtain a more precise result. MATERIAL AND METHODS: We searched PubMed to identify relevant studies, and 6 published case-control studies were retrieved, including 924 AML patients and 3832 controls. Odds ratio (OR) with corresponding 95% confidence interval (95%CI) was applied to assess the association between p53 codon 72 polymorphism and AML susceptibility. The meta-analysis was performed with Comprehensive Meta-Analysis software, version 2.2. RESULTS: Overall, no significant association between p53 codon 72 polymorphism and AML susceptibility was found in this meta-analysis (Pro vs. Arg: OR=0.94, 95%CI=0.81-1.10; Pro/Pro vs. Arg/Arg: OR=0.93, 95%CI=0.71-1.22; Arg/Pro vs. Arg/Arg: OR=0.79, 95%CI=0.55-1.13; (Pro/Pro + Arg/Pro) vs. Arg/Arg: OR=0.84, 95%CI=0.62-1.13; Pro/Pro vs. (Arg/Arg + Arg/Pro): OR=1.06, 95%CI=0.83-1.35). Similar results were also found in stratified analysis according to ethnicity and source of controls. CONCLUSIONS: Our meta-analysis demonstrates that p53 codon 72 polymorphism may not be a risk factor for AML, which should be verified in future studies.

Low expression of N-myc downstream-regulated gene 2 in oesophageal squamous cell carcinoma correlates with a poor prognosis.

BACKGROUND: It is currently unclear whether a correlation exists between N-myc downstream-regulated gene 2 (NDRG2) expression and oesophageal squamous cell carcinoma (ESCC). The aim of this study was to examine the underlying clinical significance of NDRG2 expression in ESCC patients and to investigate the effects of NDRG2 up-regulation on ESCC cell growth in vitro and in vivo. METHODS: Immunohistochemistry was used to determine the level of NDRG2 expressions in ESCC tissue, which was then compared to specific clinicopathological features in the patient and tissue specimens. Factors associated with patient survival were analysed. Moreover, the effects of up-regulating NDRG2 expression on the growth of an ESCC cell line were examined by MTT, colony formation, DNA replication activity and nude mouse model assays. RESULTS: Notably low expression of NDRG2 in ESCC patients was inversely associated with clinical stage, NM classification, histological differentiation and patients' vital status (all P < 0.05). ESCC patients expressing high levels of NDRG2 exhibited a substantially higher 5-year overall survival rate than NDRG2-negative patients. Furthermore, NDRG2 over-expression reduced the proliferation, colony formation and DNA replication activity in ESCC cells, as well as inhibiting the growth of ESCC cells in vivo. CONCLUSION: The present experiments demonstrated that NDRG2 may be a diagnostic and prognostic marker in patients with ESCC, and up-regulation of NDRG2 might act as a promising therapeutic strategy for aggressive ESCC.

Inconsistency of Bone Mineral Density Between Femoral Head and Proximal Femur After Femoral Neck Fracture Surgery Indicates Great Possibility of Femoral Head Necrosis.

On clinical observation, it was found that the bone mineral density (BMD) of the femoral head and proximal femur was not consistent in some patients with femoral neck fracture after surgery. The current study was performed to explore whether this phenomenon was associated with femoral head necrosis after surgery for femoral neck fracture. Bone mineral density inconsistency is when the difference of the sum of pixel values on both sides of the fracture line has exceeded 30%. Statistical analysis was performed on the clinical characteristics of 271 patients who had received the operation for femoral neck fracture. Chi-square test, Spearman rank correlation, independent sample t test, Kaplan-Meier method, and log-rank test, as well as univariate Cox regression and multivariate Cox regression, were used to analyze the potential relationship among related factors. It was revealed that the incidence of inconsistency in BMD between the femoral head and proximal femur was significantly increased in patients with femoral head necrosis after surgery for femoral neck fracture, and that the consistency was considerably high between BMD inconsistency and femoral head necrosis. The inconsistent BMD occurred 11.1 months earlier than the necrosis of the femoral head. Cox multivariate regression analysis indicated that the inconsistency in BMD between the femoral head and proximal femur after surgery for femoral neck fracture was an independent prognostic factor affecting femoral head necrosis. The inconsistent changes in BMD between the femoral head and proximal femur after surgery for femoral neck fracture indicate a great possibility of femoral head necrosis. [Orthopedics. 2021;44(2):e223-e228.].

Upregulated long non-coding RNAs demonstrate promising efficacy for breast cancer detection: a meta-analysis.

PURPOSE: Focusing on the latest literature, dysregulated long non-coding RNAs (lncRNAs) have been extensively explored in breast cancer (BC) research. The purpose of this meta-analysis is to synthesize the evidence on the diagnostic performance of abnormally expressed lncRNAs for BC. MATERIALS AND METHODS: Relevant studies were searched in multiple electronic databases. The Quality Assessment of Diagnosis Accuracy Studies II criteria were applied to assess the quality of included studies. The bivariate meta-analysis model was applied to synthesize the diagnostic parameters using Stata 12.0 software. Publication bias was judged in terms of the Deek's funnel plot asymmetry test. RESULTS: We included 10 eligible studies, which comprised 835 BC patients and 725 paired controls for this meta-analysis. The pooled sensitivity, specificity, diagnostic odds ratio, likelihood ratio positive, likelihood ratio negative, and area under the curve (AUC) of upregulated lncRNA expression signature in confirming BC were 0.79 (95% CI: 0.70-0.85), 0.80 (95% CI: 0.73-0.85), 14.61 (95% CI: 10.91-19.55), 3.90 (95% CI: 3.03-5.02), 0.27 (95% CI: 0.20-0.36), and 0.86, respectively. Stratified analyses yielded a sensitivity of 0.83 (95% CI: 0.80-0.86) for serum-based analysis, which was higher than plasma-based analysis, whereas plasma-based analysis revealed a greater specificity of 0.88 (95% CI: 0.85-0.91). Moreover, lncRNA-homeotic genes (HOX) transcript antisense RNA showed a pooled specificity of 0.89 (95% CI: 0.84-0.93) and AUC of 0.86, which were superior to performances by lncRNA-metastasis-associated lung adenocarcinoma transcript-1 and -H19 in diagnosing BC. Notably, the analysis based on cancer subtypes demonstrated that lncRNA expression signature could distinguish triple-negative BC (lacks estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression) from non-triple-negative BC, with an AUC of 0.85. CONCLUSION: Upregulated lncRNAs reveal an immense potential as novel non-invasive biomarker(s) that could complement BC diagnosis.

Molecular mechanism of hepatitis B virus (HBV) on suppression of raf kinase inhibitor protein (RKIP) expression.

Raf kinase inhibitor protein (RKIP) has been shown to be a suppressor of the mitogen-activated protein kinase pathway and is reported to be involved in human malignancy. However, the molecular mechanism of hepatitis B virus (HBV) in regulating RKIP expression is not yet clarified. In this study, we compared RKIP expression in 107 pairs of matched liver cancer and adjacent non-cancerous liver tissues. Among seven HBV-encoded proteins, we found HBV X (HBX) protein could significantly inhibit the expression level of RKIP, indicating that HBV could suppress RKIP expression through regulating HBX. To further elucidate the mechanism, analyses on transcriptional regulation and promoter methylation inhibition were conducted in Huh7 cells. Our results showed that HBX can interact with AP1 protein to inhibit the RKIP transcription. Moreover, we observed that the promoter methylation level of RKIP could be enhanced by HBV. In conclusion, our study revealed that RKIP could act as a molecular marker for HBV-infected liver cancer, but had no tumor-suppressing effect.

LGR5 promotes hepatocellular carcinoma metastasis through inducting epithelial-mesenchymal transition.

The purpose of the present study was to investigate the prognostic value of Leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5) in hepatocellular carcinoma (HCC) and its role in promoting HCC metastasis. The expression level of LGR5 in liver tumor tissues and adjacent non-tumor tissues were detected adopting immunohistochemistry (IHC), real-time PCR (RT-PCR) and western blot assays. Chi-square test was used to evaluate the correlation between LGR5 expression and clinicopathological characteristics. In addition, we assessed the relationship between LGR5 and two epithelial-mesenchymal transition (EMT) markers (E-cadherin and N-cadherin) in HCC tissues and cell lines. Our results showed that the expression of LGR5 was significantly higher in liver tumor tissues than in adjacent non-tumor tissues. Moreover, up-regulated LGR5 was associated with larger tumor diameter (>5cm, P=0.001), higher TNM stage (P=0.021), increased recurrence (P=0.023) and growing metastasis (P=0.030). Besides, we found that the expression level of LGR5 was correlated with E-cadherin and N-cadherin. In conclusion, up-regulated LGR5 in HCC patients is associated with malignant clinicopathological characteristics. LGR5 may promote HCC metastasis through inducting EMT process, and thus can be regarded as a candidate biomarker for prognosis and as a target in therapy.

Activation of the interleukin-34 inflammatory pathway in response to influenza A virus infection.

Interleukin 34 (IL-34) is a newly recognized cytokine that functions similarly to macrophage colony-stimulating factor. This study investigated the mechanism by which IL-34 is produced in response to exogenous pathogen infections in humans. The results showed that the IL-34 levels were higher in the serum and peripheral blood mononuclear cells (PBMCs) from 155 influenza A virus (IAV)-infected patients than in those from 145 healthy individuals. The expression level of IL-34 in IAV-infected PBMCs was blocked by IL-22-specific siRNA. This result indicated that IL-34 was induced by IL-22 in the inflammatory cascade. The mRNA and protein expression levels of IL-22 activated by IAV infection were significantly inhibited by IL-34 overexpression but induced by IL-34-specific siRNA. Thus, a feedback system most likely exists between IL-34 and IL-22. The IL-22 expression in T helper type 17 (Th17) cells of PBMCs was higher than IL-34 expression in Th17 cells of PBMCs, and there was IL-34 expression in IL-22+ Th17 cells. This result showed that the production of IL-22 and IL-34 is both from the same and different subset of cells, which indicated that the regulatory mechanism of IL-22/IL-34 is through the autocrine or paracrine systems. In conclusion, IL-34 is induced by IL-22 in the inflammatory cascade in response to IAV infection. Therefore, IL-34 is a promising target for the screening of anti-inflammatory medicines.

Promoter Methylation of the Retinoic Acid Receptor Beta2 (RARß2) Is Associated with Increased Risk of Breast Cancer: A PRISMA Compliant Meta-Analysis.

BACKGROUND: Epigenetic studies demonstrate that an association may exist between methylation of the retinoic acid receptor beta2 (RARß2) gene promoter and breast cancer onset risk, tumor stage, and histological grade, however the results of these studies are not consistent. Hence, we performed this meta-analysis to ascertain a more comprehensive and accurate association. MATERIALS AND METHODS: Relevant studies were retrieved from the PubMed, Embase and Chinese National Knowledge Infrastructure databases up to February 28, 2015. After two independent reviewers screened the studies and extracted the necessary data, meta-analysis was performed using Review Manager 5.2 software. RESULTS: Nineteen eligible articles, including 20 studies, were included in our analysis. Compared to non-cancerous controls, the frequency of RARß2 methylation was 7.27 times higher in patients with breast cancer (odds ratio (OR) = 7.27, 95% confidence interval (CI) = 3.01-17.52). Compared to late-stage RARß2 methylated patients, the pooled OR of early-stage ones was 0.81 (OR = 0.81, 95% CI = 0.55-1.17). The OR of low-grade RARß2 methylated patients was 0.96 (OR = 0.96, 95% CI = 0.74-1.25) compared to high-grade RARß2 methylated patients. CONCLUSION: RARß2 methylation is significantly increased in breast cancer samples when compared to non-cancerous controls. RARß2 could serve as a potential epigenetic marker for breast cancer detection and management.

The plasma S-adenosylmethionine level is associated with the severity of hepatitis B-related liver disease.

Alterations in methionine metabolism that involve changes in the plasma S-adenosylmethionine (SAMe) level occur in chronic liver diseases. However, no evidence is available on whether circulating SAMe is involved in the development of liver cirrhosis and liver cancer. Cross-sectional data on clinical characteristics and plasma SAMe were collected for 130 cases of chronic hepatitis B (CHB) and HCC as well as for normal volunteers. Univariate and multivariate linear regression and receiver operating characteristic curves were introduced to determine their correlations. Serum ALB and PT levels were independent clinical factors that were correlated with the plasma SAMe levels in CHB and HCC patients. A higher SAMe concentration was observed in the HCC than in the normal and CHB. By exploring the association of the Child-Pugh score with the plasma SAMe level, we found a higher SAMe level at advanced Stage C than at stage A in CHB and HCC patients. We further assessed the diagnostic performance of SAMe with respect to the stages of liver fibrosis and Child-Pugh stage. The AUROC of SAMe for the prediction of cirrhosis was 0.721, and the sensitivity and specificity was 0.707 and 0.769, respectively. The AUROC of plasma SAMe to predict Child-Pugh stage C was 0.706 in patients with CHB and 0.825 in HCC patients. The sensitivity was 0.467 and 0.800, respectively; the specificity was 0.904 and 0.781, respectively. The plasma SAMe level was positively correlated with the severity of liver disease and might be a potential noninvasive biomarker.

Hepatitis B virus inhibits the expression of CD82 through hypermethylation of its promoter in hepatoma cells.

The tumor suppressor gene CD82, also known as KAI1, may act as a general suppressor of metastasis in numerous types of cancer. It is hypothesized that downregulation of CD82 gene expression may be an important factor in the induction of hepatocellular carcinoma (HCC), however the mechanism for this requires further study. In the present study, the relative mRNA and protein expression levels of the CD82 gene were determined in HCC and adjacent non­tumor tissues. The association between the CD82 gene and the hepatitis B virus (HBV) was also investigated, by quantitative polymerase chain reaction, western blotting, luciferase reporter assays and mass spectrometry with matrix­assisted laser desorption/ionization time­of­flight mass array. CD82 expression was shown to be suppressed in response to HCC promoter methylation. Relative CD82 mRNA and protein expression levels were downregulated in HCC tissues (P<0.05). HBx protein inhibited CD82 promoter activity and subsequently the mRNA and protein expression levels. Furthermore, it was demonstrated that HBV could inhibit the expression of CD82 at the transcriptional level, and repress the activity of the CD82 promoter through hypermethylation. In addition, the methyl enzyme inhibitor 5­aza­CdR could induce the CD82 promoter activity and the relative expression level of CD82 mRNA, as observed by an increase in luciferase activity driven by the CD82 promoter. The observations of the present study suggest that hypermethylation of the CD82 promoter may be an event leading to the development of HCC. Low expression of CD82 is likely to be involved in tumor progression. HBV may inhibit the expression of CD82 through hypermethylation of the promoter in hepatoma cells.

5-Aza-2<-deoxycytidine induces hepatoma cell apoptosis via enhancing methionine adenosyltransferase 1A expression and inducing S-adenosylmethionine production.

In hepatocellular cancer (HCC), lack of response to chemotherapy and radiation treatment can be caused by a loss of epigenetic modifications of cancer cells. Methionine adenosyltransferase 1A is inactivated in HCC and may be stimulated by an epigenetic change involving promoter hypermethylation. Therefore, drugs releasing epigenetic repression have been proposed to reverse this process. We studied the effect of the demethylating reagent 5-aza-2<-deoxycitidine (5-Aza-CdR) on MAT1A gene expression, DNA methylation and S-adenosylmethionine (SAMe) production in the HCC cell line Huh7. We found that MAT1A mRNA and protein expression were activated in Huh7 cells with the treatment of 5-Aza-CdR; the status of promoter hypermethylation was reversed. At the same time, MAT2A mRNA and protein expression was significantly reduced in Huh7 cells treated with 5-Aza-CdR, while SAMe production was significantly induced. However, 5-Aza-CdR showed no effects on MAT2A methylation. Furthermore, 5-Aza-CdR inhibited the growth of Huh7 cells and induced apoptosis and through down-regulation of Bcl-2, up-regulation of Bax and caspase-3. Our observations suggest that 5-Aza- CdR exerts its anti-tumor effects in Huh7 cells through an epigenetic change involving increased expression of the methionine adenosyltransferase 1A gene and induction of S-adenosylmethionine production.