Several types of arthritis share the common feature that the generation of inflammatory mediators leads to joint cartilage degradation. However, the shared mechanism is largely unknown. H2BK120ub1 was reportedly involved in various inflammatory diseases but its role in the shared mechanism in inflammatory joint conditions remains elusive. The present study demonstrated that levels of cartilage degradation, H2BK120ub1, and its regulator WW domain-containing adapter protein with coiled-coil (WAC) were increased in cartilage in human rheumatoid arthritis (RA) and osteoarthritis (OA) patients as well as in experimental RA and OA mice. By regulating H2BK120ub1 and H3K27me3, WAC regulated the secretion of inflammatory and cartilage-degrading factors. WAC influenced the level of H3K27me3 by regulating nuclear entry of the H3K27 demethylase KDM6B, and acted as a key factor of the crosstalk between H2BK120ub1 and H3K27me3. The cartilage-specific knockout of WAC demonstrated the ability to alleviate cartilage degradation in collagen-induced arthritis (CIA) and collagenase-induced osteoarthritis (CIOA) mice. Through molecular docking and dynamic simulation, doxercalciferol was found to inhibit WAC and the development of cartilage degradation in the CIA and CIOA models. Our study demonstrated that WAC is a key factor of cartilage degradation in arthritis, and targeting WAC by doxercalciferol could be a viable therapeutic strategy for treating cartilage destruction in several types of arthritis.

Objective To investigate the effect of AU-rich element RNA-binding factor 1(AUF1)on the proliferation,apoptosis,and migration abilities of hepatocellular carcinoma(HCC)cells and possible mechanisms,and to clarify the role and molecular mechanism of AUF1 in the progression of HCC.Methods The UALCAN and TCGA-HCC databases were used to analyze the expression of AUF1 in pan-cancer and investigate the association of the expression level of AUF1 with the clinicopathological features and prognosis of HCC patients.CCK-8 assay,cell apoptosis assay,and Transwell chamber assay were used to investigate the function of AUF1 at the cellular level,and RNA-seq assay was used to investigate transcriptome changes in HCC cells after AUF1 knockdown.The t-test was used for comparison of continuous data between two groups;the Kaplan-Meier method was used to plot survival curves,and the log-rank test was used for comparison of survival rates.Results There were abnormal mRNA and protein expression levels of AUF1 in various tumor tissues compared with normal tissue(P<0.05).The mRNA expression level of AUF1 was positively correlated with the degree of HCC malignancy and the poor prognosis of early-stage HCC(P<0.05).Compared with the control group,the overexpression of exogenous AUF1 in HCC cells promoted the proliferation of HCC cells and inhibited the apoptosis and migration of HCC cells,while AUF1 knockdown inhibited HCC cell proliferation and promoted the apoptosis and migration of HCC cells.The RNA-seq analysis showed that AUF1 knockdown mainly affected the Wnt/β-catenin pathway and downregulated the protein expression level of β-catenin.Conclusion The abnormal expression of AUF1 is associated with the prognosis of early-stage HCC,and AUF1 may exert an oncogenic effect by activating the Wnt signaling pathway.

Objective To investigate the effect of cyclin D1 (with CCND1 as the gene name) on HBV replication and its potential mechanism. Methods With reference to GSE84044 dataset, the Spearman's rank correlation analysis was used to investigate the correlation between the expression levels of genes in liver tissue and serum HBV DNA load in patients with HBV-related liver fibrosis. Cyclin D1 and cyclin D1 T286A mutant were transiently expressed in the HBV cell replication model, and time-resolved immunofluorescence and quantitative real-time PCR were used to measure the levels of HBsAg/HBeAg and HBV DNA in cell culture supernatant; Western blot was used to measure the level of HBV core protein in cells; reverse-transcription quantitative real-time PCR was used to measure the level of HBV RNA in cells; dual-luciferase reporter assay was used to observe the effect of cyclin D1 on the activity of HBV basic core promoter (BCP). GSE83148 dataset was used to investigate the correlation between CCND1 and HBV-related regulatory factors. The independent samples t -test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups. Results The analysis of GSE84044 data showed that 7 cell cycle genes were significantly negatively correlated with HBV DNA load in liver tissue of the patients with HBV-related liver fibrosis (all r < -0.3, all P < 0.05), which included the CCND1 gene ( r =-0.474, P < 0.001). Exogenous expression of cyclin D1 and cyclin D1 T286A mutant reduced the levels of HBsAg, HBeAg, and HBV DNA in culture supernatant of the HBV replication cell model, as well as the levels of HBV core protein and HBV RNA in cells. Exogenous expression of cyclin D1 significantly inhibited the transcriptional activity of HBV BCP. The expression level of CCND1 in liver tissue of chronic hepatitis B patients was significantly positively correlated with the expression of APOBEC3G ( r =0.575, P < 0.001), SMC5 ( r =0.341, P < 0.001), and FOXM1 ( r =0.333, P < 0.001) which inhibited HBV replication, while it was significantly negatively correlated with the expression of the HBV entry receptor NTCP ( r =-0.511, P < 0.001) and HNF1α as the transcription factor for positive regulation of HBV replication ( r =-0.430, P < 0.001). Overexpression of cyclin D1 in HepG2 cells reduced the transcriptional levels of HNF1α and NTCP. Conclusion Cyclin D1 inhibits HBV transcription and replication possibly by downregulating the expression of HNF1α and NTCP.

ObjectiveTo investigate the effect of AU-rich element RNA-binding factor 1 (AUF1) on glypican 3 (GPC3) in hepatocellular carcinoma (HCC) and its possible mechanism. MethodsTCGA-HCC gene expression data were downloaded from Broad Institute Genome Data Analysis Center, and finally 371 HCC tissue samples with different etiologies and 50 adjacent tissue samples were included; LCI-HCC gene expression data were downloaded from GSE14520, and 214 patients with hepatitis B-associated HCC who had follow-up data were enrolled. A total of 35 primary liver cancer samples and corresponding adjacent tissue samples were collected from HCC patients who underwent radical surgery in Henan Provincial Cancer Hospital from 2009 to 2013. Immunohistochemistry was used to measure the protein expression of GPC3 and AUF1 in HCC tissue; Western Blot and qRT-PCR were used to measure the expression of GPC3 after AUF1 knockdown or overexpression in hepatoma cell lines; RNA-binding protein immunoprecipitation and RNA turnover assay were used to investigate the potential mechanism of AUF1 in regulating the expression of GPC3. The t-test was used for comparison of quantitative data between two groups, and the chi-square test was used for comparison of rates between two groups; the Kaplan-Meier method was used for survival analysis after surgery, and the log-rank test was used for comparison of survival rates. ResultsIn TCGA and LCI databases, the expression of GPC3 in HCC tissue was significantly higher than that in adjacent tissue (P＜0.05), and in TCGA database, the high expression of GPC3 was associated with the poor prognosis of HCC patients (P＜0.05). Immunohistochemistry showed that both GPC3 and AUF1 proteins are highly expressed in HCC tissue, with a positive expression rate of 77.1% (27/35) and 74.3% (26/35), respectively. In vitro experiment showed that AUF1 knockdown significantly reduced the expression of GPC3 in HepG2 and Huh-7 cells (P＜0.05), while AUF1 overexpression significantly increased the expression of GPC3 (P＜0.05). AUF1 protein could bind to GPC3 mRNA, and AUF1 knockdown reduced the stability of GPC3 mRNA. ConclusionAUF1 is an important post-transcriptional regulator of the GPC3 gene, and the abnormal high expression of AUF1 and GPC3 may be involved in the development and progression of HCC.

Objective: To explore and analyze the possible mechanism of liver injury in patients with coronavirus disease 2019 (novel coronavirus pneumonia, NCP). Methods: The correlation between ALT, AST and other liver enzyme changes condition and NCP patients’ disease status reported in the literature was comprehensively analyzed. ACE2 expression in liver tissue for novel coronavirus was analyzed based on single cell sequencing (GSE115469) data. RNA-Seq method was used to analyze Ace2 expression and transcription factors related to its expression in liver tissues at various time-points after hepatectomy in mouse model of acute liver injury with partial hepatectomy. t-test or Spearman rank correlation analysis was used for statistical analysis. Results: ALT and AST were abnormally elevated in some patients with novel coronavirus infection, and the rate and extent of ALT and AST elevation in severe NCP patients were higher than those in non-severe patients. Liver tissue results of single cell sequencing and immunohistochemistry showed that ACE2 was only expressed in bile duct epithelial cells of normal liver tissues, and very low in hepatocytes. In a mouse model of acute liver injury with partial hepatectomy, Ace2 expression was down-regulated on the first day, but it was elevated up to twice of the normal level on the third day, and returned to normal level on seventh day when the liver recovered and hepatocyte proliferation stopped. Whether this phenomenon suggests that the bile duct epithelial cells with positive expression of Ace2 participate in the process of liver regeneration after partial hepatectomy deserves further study. In RNA-Seq data, 77 transcription factors were positively correlated with the expression of ACE2 (r > 0.2, FDR < 0.05), which were mainly enriched in the development, differentiation, morphogenesis and cell proliferation of glandular epithelial cells. Conclusion We assumed that in addition to the over activated inflammatory response in patients with NCP, the up-regulation of ACE2 expression in liver tissue caused by compensatory proliferation of hepatocytes derived from bile duct epithelial cells may also be the possible mechanism of liver tissue injury caused by 2019 novel coronavirus infection.

Objective: To investigate the prognostic value of albumin/globulin ratio on postoperative survival outcomes in patients with hepatocellular carcinoma. Methods: Data of 630 patients with HCC, who underwent surgical resection from February 2009 to July 2013, were retrospectively analyzed. Patients were divided into low-value group (A/G < 1.5, defined as L group) and high-value group (A/G≥1.5, defined as H group), and their distribution characteristics were observed with the normal A/G threshold value. Independent risk factors’ affecting survival and prognosis was analyzed with univariate and multivariate Cox’s regression model. Survival trend of all patients with low-value and high-value groups in A, B and C of Barcelona stage (BCLC stage) were analyzed using the Kaplan-Meier method. Results: Multivariate analysis showed that preoperative A/G ratio (P = 0.007), alpha-fetoprotein (P < 0.001), gamma-glutamyltransferase (P = 0.006), RBC (P = 0.014), international normalized ratio (P = 0.009), preoperative BCLC staging (P < 0.001) and number of tumors (P = 0.003), and intraoperative blood transfusion (P < 0.001) were independent prognostic factors affecting long-term survival in HCC patients. The median overall survival time in-group L was 15 months, significantly lower than that in group H of 42 months (P < 0.001). Stratified analysis showed that the short-term survival advantage of patients with high A / G value was limited to those with Barcelona stage A (P < 0.001), and disappeared in patients with Barcelona stage B and C (P > 0.05). The long-term survival advantage existed in patients with Barcelona stage A (P < 0.001), B (P < 0.05), and disappeared in C (P > 0.05). Conclusion Preoperative albumin/globulin ratio can predict postoperative prognosis and survival, and direct towards the treatment for early stage of HCC and thus representing as an indicator of high clinical value.