A virus that reproduces in a host without killing cells can easily establish a successful infection. Previously, we showed that dengue-2, a virus that threatens 40% of the world, induces autophagy, enabling dengue to reproduce in cells without triggering cell death. Autophagy further protects the virus-laden cells from further insults. In this study, we evaluate how it does so; we show that dengue upregulates host pathways that increase autophagy, namely endoplasmic reticulum (ER) stress and ataxia telangiectasia mutated (ATM) signaling followed by production of reactive oxygen species (ROS). Inhibition of ER stress or ATM signaling abrogates the dengue-conferred protection against other cell stressors. Direct inhibition of ER stress response in infected cells decreases autophagosome turnover, reduces ROS production and limits reproduction of dengue virus. Blocking ATM activation, which is an early response to infection, decreases transcription of ER stress response proteins, but ATM has limited impact on production of ROS and virus titers. Production of ROS determines only late-onset autophagy in infected cells and is not necessary for dengue-induced protection from stressors. Collectively, these results demonstrate that among the multiple autophagy-inducing pathways during infection, ER stress signaling is more important to viral replication and protection of cells than either ATM or ROS-mediated signaling. To limit virus production and survival of dengue-infected cells, one must address the earliest phase of autophagy, induced by ER stress.
Background:Hepatocellular carcinoma (HCC) is one of the most important sanitary problems for its prevalence and poor prognosis. To date, no information is available on the prognostic value of the ov-serpin SERPINB3, detected in primary liver cancer but not in normal liver. The aim of the study was to analyse SERPINB3 expression in liver cancer in relation with molecular signatures of poor prognosis and with clinical outcome.Methods:Liver tumours of 97 patients were analysed in parallel for SERPINB3, TGF-β and β-catenin. In a subgroup of 67 patients with adequate clinical follow-up, the correlation of molecular findings with clinical outcome was also carried out.Results:High SERPINB3 levels were detectable in 22% of the patients. A significant correlation of this serpin with TGF-β at transcription and protein level was observed, whereas for β-catenin a strong correlation was found only at post-transcription level. These findings were in agreement with transcriptome data meta-analysis, showing accumulation of SERPINB3 in the poor-prognosis subclass (S1). High levels of this serpin were significantly associated with early tumour recurrence and high SERPINB3 was the only variable significantly associated with time to recurrence at multivariate analysis.Conclusions:SERPINB3 is overexpressed in the subset of the most aggressive HCCs.
Hepatitis B virus (HBV) infection is a major cause of liver disease worldwide. Eight genotypes and 24 subgenotypes of HBV have been identified. The aim of this study was to determine the distribution of HBV genotypes, subgenotypes and subtypes, and to understand HBV genetic variability in the HBV genome circulating in Iranian provinces. Two hundred and forty-nine sera from HBV-infected patients living in 25 provinces of Iran were collected (2004-2007). A part of the HBV S/pol and whole BCP/C genes were amplified, sequenced and then subjected to phylogenetic, recombination and genetic variability analysis. Results revealed genotype D of HBV in all samples and subgenotypes D1 (98.52%), D2 (0.74%) and D3 (0.74%) among Iranian patients living in different provinces of Iran. Subtypes ayw2 (94.4%), ayw1 (2.8%), ayw3 (2%) and ayw4 (0.4%) were deduced, on the basis of HBV small surface antigen (HBsAg) amino acid sequences. The mean percentage intra-genotypic distance of S plus core regions was 2.8%; the mean percentage inter-genotypic distance of this region between Iranian strains and genotype D isolates was 3.1%; and this rate for other genotypes was 5.2-11.4%. Various rates of point mutations have been found within different HBV genes, e.g. HBsAg (17.2%), precore-G1896A (59.5%) and Basal core promoter (BCP) double mutations (49.2%), whereas no recombination was found. In conclusion, these results indicate that the only genotype circulating in the provinces of Iran is genotype D. There exist high genetic variabilities in the S/pol and BCP/C regions among the Iranian HBV isolates.
Hepatitis B virus (HBV) isolates from Iranian patients around the country were characterized. Eighty-one complete genomes from HBV isolates were sequenced and analyzed. The studied population was grouped into three categories including inactive carriers, patients with chronic hepatitis, and patients with liver cirrhosis. Molecular and phylogenetic analyses revealed that Iranian patients were infected with HBV genotype D and subgenotype D1. The most common subtype was ayw2, followed by ayw3 and ayw4. Several deletions and insertions that had no correlation with disease outcome were observed in the HBV genomes. The most frequent mutation in the major hydrophilic region (MHR) of HBV surface antigen (HBsAg) was sP120S. Almost half of the patients studied carried precore (PC) mutant variants and one-third of the studied population was infected with variants carrying basal core promoter (BCP) mutations. PC and BCP mutations were observed in older patients, especially in those with chronic liver disease. Sixty-seven patients (82.7%) were HBeAg negative, and the prevalence of precore mutant isolates (G1896A) was higher in this group than in HBeAg-positive patients. Lamivudine drug resistance mutations were detected after 1 year of treatment in about 30% of lamivudine-treated patients. In conclusion, these results demonstrate that HBV subgenotype D1 is the only subgenotype circulating in Iran, and there is no evidence of any exotic genotype in the region. The HBV PC (G1896A) mutation may play an important role in the clinical outcome of the disease by increasing the risk of progressive liver disease among Iranian patients infected with HBV.
To identify hepatitis delta virus (HDV) genetic variability and its circulating genotypes amongst infected Iranian patients, 25 patients with positive anti-HDV status from different parts of Iran were enrolled in this cross-sectional study. A portion of the HDV delta antigen was amplified, sequenced, and subjected to molecular and phylogenetic analysis. Clinical features and virological markers were evaluated. HDV RNA could be detected in 88% of anti-HDV positive cases (22 patients) with chronic hepatitis B virus (HBV) infection and liver cirrhosis. Phylogenetic analysis revealed that all Iranian patients were infected by genotype I (clade 1) of HDV, supported by a high bootstrap value (100%, 1,000 replicates). All HDV-positive patients were coinfected with genotype D1 of HBV. No significant association was determined between demographic, clinical, and virological variables in the population studied. In conclusion, the present molecular epidemiology survey reveals that clade 1 of HDV is predominant among coinfected HBV patients in Iran.
Our results provide evidence diagnosing that the Leu/Leu genotype of EXO1 showed an inverse association with CRC. In addition, despite other investigations, we could define a significant association between the Leu allele and CRC (p = 0.001).
BackgroundWilson disease (WD) is an autosomal recessive disorder. The WD gene, ATP7B, encodes a copper-transporting ATPase involved in the transport of copper into the plasma protein ceruloplasmin and in excretion of copper from the liver. ATP7B mutations cause copper to accumulate in the liver and brain.ObjectivesWe examined the ATP7B mutation spectrum in Wilson disease patients in Iran.Patients and MethodsGenomic DNA was extracted from patients with Wilson disease. The entire coding region of the ATP7B gene was amplified using PCR and analyzed using direct sequencing.ResultsWe identified five novel mutations in 5 Iranian patients with Wilson disease. The first was a transversion, c.2363C > T, which led to an amino acid change from threonine to isoleucine. The second mutation was a deletion, c.2532delA (Val845Ser), which occurred in exon 10. The third mutation was a transition mutation, c.2311C > G (Leu770Leu), which occurred in the TM4 domain of the ATP7B protein. The fourth mutation was a transversion, (c.3061G > A) (Lys1020Lys), in exon 14. Lastly, we identified a transversion, c.3206C > A (His1069Asn) in exon 14 which led to a change in function of the ATP loop domain of the ATP7B protein. The H1069Q mutation was identified as the most common mutation in our study population.ConclusionsBased on our findings, the H1069Q may be a biomarker that can be used in a rapid detection assay for diagnosing WD patients
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.