Up-regulation of A20 gene expression in peripheral blood mononuclear cells is associated with acute-on-chronic hepatitis B liver failure

Hypermethylation of Cyclin D2 Predicts Poor Prognosis of Hepatitis B Virus-Associated Hepatocellular Carcinoma after Hepatectomy

Prognosis of patients with hepatocellular carcinoma remains poor because of progression of hepatocellular carcinoma and high recurrence rates. Cyclin D2 (CCND2) plays a vital role in regulating the cell cycle; indeed, aberrant methylation of CCND2 is involved in the development of hepatocellular carcinoma. Therefore, we aimed to investigate levels of CCND2 methylation in patients with hepatitis B virus (HBV)-associated hepatocellular carcinoma and to evaluate its prognostic significance after hepatectomy. In total, 257 subjects were enrolled (166 hepatocellular carcinoma patients undergoing surgical resection, 61 chronic hepatitis B (CHB) patients, and 30 healthy controls). CCND2 methylation in peripheral blood mononuclear cells was measured quantitatively using MethyLight. We found that CCND2 methylation levels in patients with HBV-associated hepatocellular carcinoma were significantly higher than in CHB patients (P < 0.001) or healthy controls (P < 0.001). Within the hepatocellular carcinoma group, CCND2 methylation levels were higher in patients with portal vein invasion, early tumor recurrence, TNM III/IV stage, and tumor size ≥ 5 cm (P < 0.05). Furthermore, higher levels of CCND2 methylation were associated with worse overall survival and disease-free survival (P = 0.005 and P < 0.001, respectively). Multivariate analysis identified CCND2 methylation as an independent prognostic factor for early tumor recurrence (P = 0.021), overall survival (P = 0.022), and disease-free survival (P < 0.001) in hepatocellular carcinoma patients after resection. In conclusion, hypermethylation of CCND2 may have clinical utility for predicting a high risk of poor prognosis and early tumor recurrence in patients with HBV-associated hepatocellular carcinoma after hepatectomy.

Aberrant GSTP1 promoter methylation predicts poor prognosis of acute-on-chronic hepatitis B pre-liver failure

It has been demonstrated that glutathione-S-transferase P1 (GSTP1) could protect cells from DNA damage mediated by oxidizing agents or electrophiles in hepatic inflammatory response. Our study evaluated the methylation status and the predictive value for prognosis of GSTP1 promoter region in patients with acute-on-chronic hepatitis B pre-liver failure (pre-ACHBLF). Methylation status of GSTP1 promoter in peripheral blood mononuclear cells (PBMCs) and plasma was measured in 103 patients with pre-ACHBLF, 80 patients with chronic hepatitis B (CHB) and 30 healthy controls (HCs) by methylation-specific polymerase chain reaction. The mRNA level of GSTP1 was detected by quantitative real-time polymerase chain reaction. The methylation frequency of GSTP1 promoter region in patients with pre-ACHBLF (35/103 in PBMCs and 33/103 in plasma) was significantly higher than CHB (2/80) and HCs (0/30), respectively. The mRNA level of GSTP1 in patients with pre-ACHBLF was significantly lower than CHB and HCs. Additionally, pre-ACHBLF patients with methylated GSTP1 presented strikingly higher incidence of ACHBLF than those without. Of note, GSTP1 methylation presented distinctly better performance than model for end-stage liver disease score [area under the receiver operating characteristic curves (AUCs) 0.825 in PBMCs and 0.798 in plasma VS 0.589; AUC 0.804 in PBMCs and 0.779 in plasma VS 0.622; AUC 0.767 in PBMCs and 0.744 in plasma VS 0.602, respectively] when used to predict the 1-, 2- or 3-month incidence of ACHBLF in patients with pre-ACHBLF. Aberrant methylation of GSTP1 has potential to be a prognostic biomarker for pre-ACHBLF.

Elevated serum A20 is associated with severity of chronic hepatitis B and A20 inhibits NF-κB-mediated inflammatory response

A20 is a powerful suppressor for inflammatory response. This study aims to determine A20 level in patients with chronic hepatitis B (CHB), and analyze its association with the disease severity. The role of A20 in inflammatory response was further investigated in vivo and in vitro. Our results showed significantly higher A20 in both serum and liver tissues in CHB patients than in health controls. Serum A20 level was positively correlated with ALT, AST and TNF-α. To induce hepatitis with inflammation and liver injury, mice were injected intraperitoneally with D-galactosamine (D-GalN), resulting in rapid increase of A20 in serum and liver tissues. Consistently, HepG2 and Huh-7 cells exposed to Lipopolysaccharide (LPS) or D-GalN were promoted to express A20. Moreover, overexpression or knockdown of A20 inhibited or increased TNF-α secretion separately. A20 significantly reduced pro-inflammatory cytokines expression and down-regulated phospho-IκBα and phospho-p65 in both cells. In conclusion, elevated A20 expression is involved in the severity of CHB, suggesting A20 to be a possible serological biomarker for the disease prognosis. Additionally, the inflammatory response is attenuated by A20 through inhibiting NF-κB activity, which partially contributes to the hepato-protective function of this molecule. Thus, up-regulating A20 might be a potential strategy for preventing the progress of CHB.

A20 Ameliorates Intracerebral Hemorrhage-Induced Inflammatory Injury by Regulating TRAF6 Polyubiquitination

Reducing excessive inflammation is beneficial for the recovery from intracerebral hemorrhage (ICH). Here, the roles and mechanisms of A20 (TNFAIP3), an important endogenous anti-inflammatory factor, are examined in ICH. A20 expression in the PBMCs of ICH patients and an ICH mouse model was detected, and the correlation between A20 expression and neurologic deficits was analyzed. A20 expression was increased in PBMCs and was negatively related to the modified Rankin Scale score. A20 expression was also increased in mouse perihematomal tissues. A20^-/- and A20-overexpressing mice were generated to further analyze A20 function. Compared with wild-type (WT) mice, A20^-/- and A20-overexpressing mice showed significant increases and decreases, respectively, in hematoma volume, neurologic deficit score, mortality, neuronal degeneration, and proinflammatory factors. Moreover, WT-A20^-/- parabiosis was established to explore the role of A20 in peripheral blood in ICH injury. ICH-induced damage, including brain edema, neurologic deficit score, proinflammatory factors, and neuronal apoptosis, was reduced in A20^-/- parabionts compared with A20^-/- mice. Finally, the interactions between TRAF6 and Ubc13 and UbcH5c were increased in A20^-/- mice compared with WT mice; the opposite occurred in A20-overexpressing mice. Enhanced IκBα degradation and NF-κB activation were observed in A20^-/- mice, but the results were reversed in A20-overexpressing mice. These results suggested that A20 is involved in regulating ICH-induced inflammatory injury in both the central and peripheral system and that A20 reduces ICH-induced inflammation by regulating TRAF6 polyubiquitination. Targeting A20 may thus be a promising therapeutic strategy for ICH.

Altered expression of A20 gene in peripheral blood mononuclear cells is associated with the progression of chronic hepatitis B virus infection

A20 is an important negative immune regulator but its role in chronic hepatitis B virus (HBV) infection is still unknown. This present study was to investigate the potential role of A20 gene in the progression of chronic HBV infection. A total of 236 chronic HBV patients were included and consisted of 63 hepatocellular carcinoma (HCC), 87 liver cirrhosis (LC) and 86 chronic hepatitis B (CHB). The mRNA level of A20 gene in peripheral blood mononuclear cells was determined using quantitative real-time polymerase chain reaction. Receptor operating characteristic curve (ROC) was performed to determine the diagnostic value of A20 mRNA in different stages of chronic HBV infection. A20 mRNA levels in all HBV patients were significantly higher than healthy controls (n=30), of whom HCC and LC patients showed higher A20 mRNA level than CHB patients. In CHB patients, A20 mRNA was closely associated with alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin. In LC patients, A20 mRNA was significantly associated with ALT, AST, albumin, haemoglobin and platelet. In HCC patients, elevated A20mRNA was also observed in patients with vascular invasion, liver cirrhosis and ascites, compared with those without. ROC analysis revealed that A20 mRNA could effectively discriminate LC from CHB, decompensated LC from compensated LC, and HCC from CHB. In conclusion, A20 mRNA expression in peripheral blood mononuclear cells was associated with dynamic progression of chronic HBV infection. A20 gene might be a potential biomarker to determine the different stages of chronic HBV infection.