Dicer interacts with SIRT7 and regulates H3K18 deacetylation in response to DNA damaging agents.

Dicer participates in heterochromatin formation in fission yeast and plants. However, whether it has a similar role in mammals remains controversial. Here we showed that the human Dicer protein interacts with SIRT7, an NAD(+)-dependent H3K18Ac (acetylated lysine 18 of histone H3) deacetylase, and holds a proportion of SIRT7 in the cytoplasm. Dicer knockdown led to an increase of chromatin-associated SIRT7 and simultaneously a decrease of cytoplasmic SIRT7, while its overexpression induced SIRT7 reduction in the chromatin-associated fraction and increment in the cytoplasm. Furthermore, DNA damaging agents promoted Dicer expression, leading to decreased level of chromatin-associated SIRT7 and increased level of H3K18Ac, which can be alleviated by Dicer knockdown. Taken together with that H3K18Ac was exclusively associated with the chromatin, our findings suggest that Dicer induction by DNA damaging treatments prevents H3K18Ac deacetylation, probably by trapping more SIRT7 in the cytoplasm.

Development and validation of a prognostic nomogram for acute-on-chronic hepatitis B liver failure.

BACKGROUND AND AIM: Determining individual risk of short-term mortality in patients with acute-on-chronic hepatitis B liver failure (ACHBLF) is a difficult task. We aimed to develop and externally validate a prognostic nomogram for ACHBLF patients. METHODS: The nomogram was built to estimate the probability of 30-day, 60-day, 90-day, and 60-month survival based on an internal cohort of 246 patients with ACHBLF. The predictive accuracy and discriminative ability of nomogram were determined by a concordance index (C-index), calibration curve, and time-dependent receiver operating characteristics (tdROC), comparing with model for end-stage liver disease (MELD) score. The results were validated using bootstrap resampling and an external cohort of 138 patients. Furthermore, we plotted decision curves to evaluate the clinical usefulness of nomogram. RESULTS: Independent factors derived from multivariable Cox analysis of training cohort to predict mortality were age, total bilirubin, serum sodium, and prothrombin activity, which were all assembled into nomogram. The calibration curves for probability of survival showed optimal agreement between nomogram prediction and actual observation. The C-index of nomogram was higher than that of MELD score for predicting survival (30-day, 0.809 vs 0.717, P < 0.001; 60-day, 0.792 vs 0.685, P < 0.001; 90-day, 0.779 vs 0.678, P < 0.001; 6-month, 0.781 vs 0.677, P < 0.001). Additionally, tdROC and decision curves also showed that nomogram was superior to MELD score. The results were confirmed in validation cohort. CONCLUSIONS: The prognostic nomogram provided an individualized risk estimate of short-term survival in patients with ACHBLF, offering to clinicians to improve their abilities to assess patient prognosis.

MicroRNA-581 promotes hepatitis B virus surface antigen expression by targeting Dicer and EDEM1.

Hepatitis B virus surface antigen (HBsAg) is an important risk factor for hepatocellular carcinoma (HCC) and is downregulated during hepatocarcinogenesis. MicroRNAs (miRNAs) are frequently deregulated in HCC tissues. However, whether the deregulation of certain miRNAs in HCC has an impact on HBsAg expression remains unclear. We found here that microRNA-581 (miR-581), which is deregulated during hepatocarcinogenesis, promoted HBsAg expression. Additionally, miR-581 targeted Dicer and endoplasmic reticulum degradation-enhancing alpha-mannosidase-like protein 1 (EDEM1) and repressed their expression. Although Dicer cannot process HBV transcripts, Dicer knockdown led to increased HBsAg secretion, most likely due to a reduction in the levels of Dicer-processed 7SL RNA fragments. Moreover, Dicer-processed 7SL RNA fragments partially inhibited the ability of miR-581 to stimulate HBsAg expression. Furthermore, we found that forced EDEM1 expression inhibited miR-581-mediated induction of HBsAg. Finally, transfection of miR-581 into HepG2.2.15 cells promoted cell proliferation and led to upregulation of genes involved in development, cell proliferation and protein secretion. Altogether, we conclude that miR-581 promotes HBsAg expression by targeting Dicer and EDEM1. Our findings suggest that downregulation of miR-581 during hepatocarcinogenesis may lead to a reduction in HBsAg expression and impede HCC development.

Neutrophil-lymphocyte ratio predicts hospital-acquired bacterial infections in decompensated cirrhosis.

BACKGROUND: Bacterial infection is a frequent complication and severe burden in cirrhotic patients. We determined the utility of neutrophil-to-lymphocyte ratio (NLR) to predict the hospital-acquired (HA) bacterial infections episode in patients with decompensated cirrhosis. METHODS: We retrospectively included 2066 consecutive decompensated cirrhotic patients from two separate tertiary hospitals, divided into training (n=1377) and validation (n=689) set. All data were collected on admission and all overt bacterial infections occurring after >48h of hospital stay were registered. RESULTS: The incidence of HA bacterial infections in training and validation cohort was 35.87% and 31.05% respectively. Multivariate analysis showed that total bilirubin (TBil), albumin, white blood cell count (WBC) and NLR were independent predictors of HA bacterial infections. We established a Model_NTWA using these four variables and a Model_TWA which did not include NLR. Areas under the curves (AUC) of Model_NTWA (0.859) and NLR (0.824) were higher than which of Model_TWA (0.713), WBC (0.675), TBil (0.593) and Albumin (0.583). Consistent with training cohort, validation cohort showed similar results. Patients with NLR of at least 4.33 had a significantly lower survival (P<0.001). CONCLUSIONS: NLR can be used as a novel noninvasive marker to predict the occurrence of HA bacterial infections in decompensated cirrhotic patients.

A microRNA expression profile for vascular invasion can predict overall survival in hepatocellular carcinoma.

BACKGROUND: The presence of vascular invasion (VI) in pathology specimens is a well-known unfavorable prognostic factor of hepatocellular carcinoma (HCC) recurrence and overall survival (OS). We investigated the vascular invasion related microRNA (miRNA) expression profiles and potential of prognostic value in HCC. METHODS: MiRNA and mRNA expression data for HCC were accessed from The Cancer Genome Atlas (TCGA). LASSO logistic regression models were used to develop a miRNA-based classifier for predicting VI. The predictive capability was accessed by area under receiver operating characteristics (AUC). Concordance index (C-index) and time-dependent receiver operating characteristic (td-ROC) were used to determine its prognostic value. We validated the predictive and prognostic accuracy of this classifier in an external independent cohort of 127 patients. Functionally relevant targets of miRNAs were determined using miRNA target prediction, experimental validation and correlation of miRNA and mRNA expression data. RESULTS: A 16-miRNA-based classifier was developed which identified VI accurately, with AUC of 0.731 and 0.727 in TCGA set and validation cohort, respectively. C-index and td-ROC showed that the classifier was able to stratify patients into risk groups strongly associated with OS. When stratified by tumor characteristics, the classifier was still a clinically and statistically significant prognostic model. The predictive and prognostic accuracy of the classifier was confirmed in validation cohort. Vascular invasion related miRNA/target pairs were identified by integrating expression patterns of predicted targets, which were validated in cell lines. CONCLUSIONS: A multi-miRNA-based classifier developed based on the presence of VI, which could effectively predict OS in HCC.

C-reactive protein-to-albumin ratio is a predictor of hepatitis B virus related decompensated cirrhosis: time-dependent receiver operating characteristics and decision curve analysis.

BACKGROUND AND AIMS: Hepatitis B virus (HBV) infection remains a major health problem and HBV-related-decompensated cirrhosis (HBV-DC) usually leads to a poor prognosis. Our aim was to determine the utility of inflammatory biomarkers in predicting mortality of HBV-DC. MATERIALS AND METHODS: A total of 329 HBV-DC patients were enrolled. Survival estimates for the entire study population were generated using the Kaplan-Meier method. The prognostic values for model for end-stage liver disease (MELD) score, Child-Pugh score, and inflammatory biomarkers neutrophil/lymphocyte ratio, C-reactive protein-to-albumin ratio (CAR), and lymphocyte-to-monocyte ratio (LMR) for HBV-DC were compared using time-dependent receiver operating characteristic curves and time-dependent decision curves. RESULTS: The survival time was 23.1±15.8 months. Multivariate analysis identified age, CAR, LMR, and platelet count as prognostic independent risk factors. Kaplan-Meier analysis indicated that CAR of at least 1.0 (hazard ratio, 7.19; 95% confidence interval, 4.69-11.03), and LMR less than 1.9 (hazard ratio, 2.40; 95% confidence interval, 1.69-3.41) were independently associated with mortality of HBV-DC. The time-dependent receiver operating characteristic indicated that CAR showed the best performance in predicting mortality of HBV-DC compared with LMR, MELD score, and Child-Pugh score. The results were also confirmed by time-dependent decision curves. CONCLUSION: CAR and LMR were associated with the prognosis of HBV-DC. CAR was superior to LMR, MELD score, and Child-Pugh score in HBV-DC mortality prediction.

Prognostic value of DNA repair based stratification of hepatocellular carcinoma.

Aberrant activation of DNA repair is frequently associated with tumor progression and response to therapy in hepatocellular carcinoma (HCC). Bioinformatics analyses of HCC data in the Cancer Genome Atlas (TCGA) were performed to define DNA repair based molecular classification that could predict the prognosis of patients with HCC. Furthermore, we tested its predictive performance in 120 independent cases. Four molecular subgroups were identified on the basis of coordinate DNA repair cluster (CDRC) comprising 15 genes in TCGA dataset. Increasing expression of CDRC genes were significantly associated with TP53 mutation. High CDRC was significantly correlated with advanced tumor grades, advanced pathological stage and increased vascular invasion rate. Multivariate Cox regression analysis indicated that the molecular subgrouping was an independent prognostic parameter for both overall survival (p = 0.004, hazard ratio (HR): 2.989) and tumor-free survival (p = 0.049, HR: 3.366) in TCGA dataset. Similar results were also obtained by analyzing the independent cohort. These data suggest that distinct dysregulation of DNA repair constituents based molecular classes in HCC would be useful for predicting prognosis and designing clinical trials for targeted therapy.

Hepatocellular carcinoma associated microRNA expression signature: integrated bioinformatics analysis, experimental validation and clinical significance.

microRNA (miRNA) expression profiles varied greatly among current studies due to different technological platforms and small sample size. Systematic and integrative analysis of published datesets that compared the miRNA expression profiles between hepatocellular carcinoma (HCC) tissue and paired adjacent noncancerous liver tissue was performed to determine candidate HCC associated miRNAs. Moreover, we further validated the confirmed miRNAs in a clinical setting using qRT-PCR and Tumor Cancer Genome Atlas (TCGA) dataset. A miRNA integrated-signature of 5 upregulated and 8 downregulated miRNAs was identified from 26 published datesets in HCC using robust rank aggregation method. qRT-PCR demonstrated that miR-93-5p, miR-224-5p, miR-221-3p and miR-21-5p was increased, whereas the expression of miR-214-3p, miR-199a-3p, miR-195-5p, miR-150-5p and miR-145-5p was decreased in the HCC tissues, which was also validated on TCGA dataset. A miRNA based score using LASSO regression model provided a high accuracy for identifying HCC tissue (AUC = 0.982): HCC risk score = 0.180E_miR-221 + 0.0262E_miR-21 - 0.007E_miR-223 - 0.185E_miR-130a. E_miR-n = Log 2 (expression of microRNA n). Furthermore, expression of 5 miRNAs (miR-222, miR-221, miR-21 miR-214 and miR-130a) correlated with pathological tumor grade. Cox regression analysis showed that miR-21 was related with 3-year survival (hazard ratio [HR]: 1.509, 95%CI: 1.079-2.112, P = 0.016) and 5-year survival (HR: 1.416, 95%CI: 1.057-1.897, P = 0.020). However, none of the deregulated miRNAs was related with microscopic vascular invasion. This study provides a basis for further clinical application of miRNAs in HCC.

[Clinical study on treatment of alcoholic liver disease by qinggan huoxue recipe].

OBJECTIVE: To study the effect of Qinggan Huoxue recipe (QGHXR) in treating alcoholic liver disease (ALD). METHODS: By adopting the multi-centered, randomized and controlled method, the patients were divided in to the QGHXR group (60 patients) treated orally by QGHXR, the XCHG group (30 patients) treated orally by Xiaochaihu granule and the control group (30 patients) treated orally by conventional therapy such as glucurolactone, vitamin C. The changes in symptoms, signs, liver function, blood lipid, liver fibrosis markers, cytokines, lipid superoxidation parameters and B-untrasonographic figure after treatment of the two groups were observed. RESULTS: The total therapeutic efficacy of QGHXR, improvements in anorexia, nausea, vomiting and jaundice as well as effect in reducing blood levels of alanine transaminase (ALT), aspartate aminotransferase (AST) and triglyceride (TG) were superior in the QGHXR group to those in the other two groups (P < 0.01), and the effect in decreasing gamma-glutamyl transferase (GGT) and very low-density lipoprotein (VLDL) in the QGHXR group was more significant than that in the control group (P < 0.01). QGHXR also showed effects in lowering levels of liver fibrosis markers and cytokines, alleviating the anti-lipid superoxidation damage in liver, and could markedly improve the degree of fatty liver. CONCLUSION: QGHXR shows obvious therapeutic effect in treating ALD, the mechanism could possibly be related with its effects in antagonizing lipid superoxidation, stabilizing hepatic cell membrane, adjusting the lipid metabolic disturbance of liver, regulating immune function, anti-liver fibrosis and promoting the intrahepatic metabolism of alcohol.

Decreased dicer expression enhances SRP-mediated protein targeting.

We have shown that Dicer processes 7SL RNA into different fragments ranging from ∼20 to more than 200 nucleotides. Here we addressed the molecular functions of these 7SL RNA fragments and found that some of them functioned as dominant-negative regulators of the full-length 7SL RNA, interfering with signal recognition particle (SRP) complex formation. Transfection of these 7SL RNA fragments inhibited the expression of cell surface glycoproteins, the targeting of a reporter protein to the endoplasmic reticulum, and the secretion of secreted alkaline phosphatase. These results suggest that some Dicer-processed 7SL RNA fragments interfered with SRP-mediated protein targeting. Moreover, we showed that Dicer knockdown enhanced SRP-mediated protein targeting and that transfection of a mixture of the 7SL RNA fragments partially restored this effect. Our data indicate that Dicer can fine-tune the efficiency of SRP-mediated protein targeting via processing a proportion of 7SL RNA into fragments of different lengths.