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Background & Aims: Men have a higher incidence of hepatocellular carcinoma (HCC) than women, which is believed to partly be because of protective effects of estrogen. We sought to determine whether there were differences in levels of microRNA (miRNA) molecules between male and female HCC samples. Methods: The expression profiles of a panel of candidate miRNAs were compared between male and female HCC tissues using the TaqMan miRNA assay. A luciferase reporter assay was used to identify mRNA targets recognized by specific miRNAs. The levels of pri- and pre-miRNA for each specific miRNA were assayed by quantitative reverse-transcription polymerase chain reaction to delineate the step deregulated in the biogenesis process. Finally, a colorimetric assay was used to determine the effect of specific miRNAs on hepatoma cell proliferation. Results: The miR-18a miRNA increased specifically in samples from female HCC patients (female/male ratio, 4.58; P = .0023). The gene ESR1, which encodes the estrogen receptor-α (ERα), was identified as a target of miR-18a. miR-18a can repress ERα translation by binding to its mRNA at the 3′ untranslated region. Increased levels of miR-18a in female HCC tissues correlated with reduced ERα expression; the level of pre-miR-18a changed in concordance with that of mature miR-18a in these tissues. Overexpression of miR-18a decreased ERα levels but stimulated the proliferation of hepatoma cells. Conclusions: This study provides a novel miRNA-mediated regulatory mechanism for controlling ERα expression in hepatocytes. miR-18a prevents translation of ERα, potentially blocking the protective effects of estrogen and promoting the development of HCC in women. [Copyright &y& Elsevier]

Background & Aims: The interactions among pre-S deletion, precore (PC) mutation, and basal core promoter (BCP) mutation in various stages of chronic hepatitis B virus (HBV) infection remain unclear and were thus investigated in this study. Methods: The sequences of the pre-S region and the BCP (A1762T, G1764A) and PC (G1896A) mutations were determined in 46 HBV chronic carriers (CC) and 106 age-matched carriers with different stages of liver diseases, including 38 chronic hepatitis (CH), 18 cirrhosis (LC), and 50 hepatocellular carcinoma (HCC). Results: A higher prevalence of pre-S deletion and BCP and PC mutations was found in carriers with progressive liver diseases compared with the CC group. By logistic regression analysis, patients with pre-S deletion and BCP mutation were significantly associated with the development of progressive liver diseases than those without. Combination of mutations rather than single mutation was associated with the development of progressive liver diseases, especially in combination with pre-S deletion. Sequencing analysis showed that the deleted regions were more often in the 3′ terminus of pre-S1 and the 5′ terminus of pre-S2. Further mapping of these pre-S deletion sequences found that all the deletion regions encompassed T- and B-cell epitopes, and most of them lost 1 or more functional sites. Conclusions: Our data indicate that patients with progressive liver diseases have a higher frequency of pre-S deletion. [Copyright &y& Elsevier]

Background & Aims: Patients with chronic hepatitis B virus (HBV) infection have a high risk for developing hepatocellular carcinoma (HCC). Patients with lower levels of hepatitis B surface antigen (HBsAg) have higher chances of losing HBsAg than those with high levels. However, little is known about whether higher levels of HBsAg increase risk for HCC. Methods: We followed 2688 Taiwanese HBsAg-positive patients without evidence of cirrhosis for a mean time period of 14.7 years. In addition to the known risk factors of HCC, we investigated the association between levels of HBsAg and development of HCC. Results: Of the patients followed, 191 developed HCC, with an average annual incidence rate of 0.5%. Baseline levels of HBsAg and HBV were associated with development of HCC, and risk increased with level. Compared to HBsAg level, by receiver operating characteristic curve analysis, HBV DNA level better predicted the development of HCC during 10-year and 15-year periods (both, P < .001). However, when we evaluated hepatitis B e antigen−negative patients with levels of HBV DNA <2000 IU/mL, factors that determined HCC risk included sex, age, and levels of alanine aminotransferase and HBsAg (≥1000 IU/mL), but not level of HBV DNA. Multivariate analysis showed that the adjusted hazard ratio for HCC in patients with levels of HBsAg ≥1000 IU/mL versus <1000 IU/mL was 13.7 (95% confidence interval: 4.8−39.3). Conclusions: Among patients infected with HBV genotype B or C, determinants of HCC risk include their sex, age, hepatitis B e antigen status, HBV genotype, and levels of alanine aminotransferase and HBV DNA, but not level of HBsAg. Among hepatitis B e antigen−negative patients with low viral loads, HCC risk is determined by levels of HBsAg and alanine aminotransferase and age, but not HBV DNA. [Copyright &y& Elsevier]

Background & Aims: This study aimed at investigating mutations in the hepatitis B surface protein (HBsAg) in occult hepatitis B virus (HBV) infection (OBI) and their influence on viral antigenicity and phenotype. Methods: The characteristics of 61 carriers with OBI (OBI group), 153 HBsAg(+) carriers with serum HBsAg ⩽100IU/ml (HBsAg-L group) and 54 carriers with serum HBsAg >100IU/ml (HBsAg-H group) from 38,499 blood donors were investigated. Mutations in the major hydrophilic region (MHR) of the viral sequences were determined. Thirteen representative MHR mutations observed in OBI sequences were antigenically characterized with a panel of monoclonal antibodies (MAbs) and commercial HBsAg immunoassays and functionally characterized in HuH7 cells and hydrodynamically injected mice. Results: Of 61 OBI sequences, 34 (55.7%) harbored MHR mutations, which was significantly higher than the frequency in either the HBsAg-L (34.0%, p =0.003) or the HBsAg-H group (17.1%, p <0.001). Alterations in antigenicity induced by the 13 representative MHR mutations identified in the OBI group were assessed by reacting recombinant HBV mutants with 30 different MAbs targeting various epitopes. Four out of the 13 mutations (C124R, C124Y, K141E, and D144A) strongly decreased the analytical sensitivity of seven commercial HBsAg immunoassays, and 10 (G119R, C124Y, I126S, Q129R, S136P, C139R, T140I, K141E, D144A, and G145R) significantly impaired virion and/or S protein secretion in both HuH7 cells and mice. Conclusions: MHR mutations alter antigenicity and impair virion secretion, both of which may contribute to HBsAg detection failure in individuals with OBI. [Copyright &y& Elsevier]

Background & Aims: Previously we reported that Akt inactivation determines the sensitivity of hepatocellular carcinoma (HCC) cells to bortezomib. Here we report that combined treatment with sorafenib and bortezomib shows synergistic effects in HCC. Methods: HCC cell lines (PLC/PRF/5, Huh-7, and Hep3B) were treated with sorafenib and/or bortezomib and analyzed in terms of apoptosis signal transduction. In vivo efficacy was determined in nude mice with PLC/PRF/5 xenografts. Results: Pretreatment with sorafenib enhanced bortezomib-induced apoptotic cell death by restoring bortezomib’s ability to inactivate Akt in PLC/PRF/5 cells. Knocking down Akt1 by RNA-interference overcame apoptotic resistance to bortezomib in PLC/PRF/5 cells and ectopic expression of active Akt in HCC cells abolished the bortezomib sensitizing effect of sorafenib, indicating Akt inactivation plays a key role in mediating the combinational effects. Moreover, okadaic acid, a protein phosphatase 2A (PP2A) inhibitor, reversed down-regulation of phospho-Akt (P-Akt) expression induced by co-treatment with sorafenib and bortezomib, and 1, 9 di-deoxy-forskolin, a PP2A agonist, restored bortezomib’s effect on P-Akt and apoptosis. Importantly, silencing of PP2A by RNA-interference reduced the apoptotic effect induced by sorafenib–bortezomib co-treatment, indicating that PP2A is indispensable for mediating the effects of these drugs. Notably, sorafenib with bortezomib increased PP2A activity in PLC/PRF/5 cells without altering protein levels of PP2A complex or the interaction between PP2A and Akt proteins. Finally, sorafenib plus bortezomib significantly suppressed PLC/PRF/5 xenograft tumor growth, down-regulated P-Akt expression, and up-regulated PP2A activity. Conclusions: The combination of sorafenib and bortezomib shows synergy in HCC through PP2A-dependent Akt inactivation. [Copyright &y& Elsevier]

Background/Aims: The infectivity of occult hepatitis B virus (HBV), defined as HBsAg-negative but HBV DNA-positive, after transfusion has been low but not negligible. To address this, we investigated the incidence of post-transfusion HBV infection after receiving screened blood units in Taiwan. Methods: Consecutive HBV-naïve (anti-HBc-negative) recipients with normal ALT were followed for HBV DNA and serologic markers before and after transfusion. Among 4448 blood recipients, 467 (10.5%) were anti-HBc-negative. Post-transfusion 6-month follow-up was completed for 327. We identified 5 (1.5%) who developed hepatitis B viremia 1 week after transfusion. Three were children who later seroconverted to anti-HBc but with normal ALT indicating subclinical acute infection, despite all had anti-HBs from previous vaccination. One had transient transfusion-transmitted HBV without seroconversion to anti-HBc and one possibly had occult HBV infection. Our findings suggested the possibility that occult HBV infection was transmissible by transfusion. The incidence of post-transfusion acute HBV infection was 0.9% (100 per million units) in naïve recipients in Taiwan, a figure 7∼40-fold higher than in developed countries. Moreover, some vaccinated children with anti-HBs were still susceptible. Conclusions: Therefore, despite active immunization, sensitive screening assays for occult HBV infection such as nucleic acid amplification test could be considered in endemic areas. [Copyright &y& Elsevier]