Background & Aims The pleiotropic hepatitis B virus (HBV) x protein (HBx), associated with hepatocellular carcinoma (HCC), has been implicated in the deregulation of cellular gene expression at the ...transcriptional level. To date, it remains unknown if HBx regulates the expression of miRNAs which play important roles in gene-regulation at the post-transcriptional and/or translational level. Methods miRNA microarrays were employed to compare the expression of cellular miRNAs in HBx-versus control-HepG2 cells. Reverse-transcription Taqman realtime-PCR was used to examine let-7a expression in normal liver as well as paired HCC-tumor and adjacent non-tumorous liver. Let-7a miRNA was functionally characterized in cells with transiently altered let-7a expression. The direct target of let-7a was identified in silico and validated using 3′UTR-reporter assay. Results HBx up-regulates 7 and down-regulates 11 miRNAs, including the let-7 family. HBx expression was found to have a significant inverse correlation with the expression of the highly-expressed members of the let-7 family in HCC patients, highlighting the clinical relevance of our observations. Further characterization of let-7a, the most highly expressed let-7 family member, revealed that it negatively regulates cellular proliferation partly through targeting signal transducer and activator of transcription 3 (STAT3). HBx-mediated down-regulation of let-7a and up-regulation of STAT3 supports cell proliferation in HBx cells. Conclusion This study thus represents the first demonstration of HBx’s ability to deregulate cellular miRNA expression. The deregulation of the expression of the let-7 family of miRNAs by HBx may represent a potential novel pathway through which HBx acts to deregulate cell proliferation leading to hepatocarcinogenesis.
Childhood diabetes is a rising concern as the overall annual increase in diabetes among children/adolescents is estimated to be around 3% over the past decade. Diabetes management places ...children/adolescents and their parents at greater risks of psychological distress. This study aims to measure the levels of diabetes-related emotional distress in children/adolescents with diabetes and their caregiving parents and to identify associations between sociodemographic characteristics and clinical variables in Singapore. A cross-sectional study was conducted using validated questionnaires. Ninety-two parent–child/adolescent dyads completed self-reported questionnaires. Elevated levels of diabetes-related distress were found in both children/adolescents with diabetes and their parents. Female children/adolescents with diabetes, low-income households, and less-educated parents of children/adolescents with diabetes were more susceptible to diabetes-related distress. It is important for healthcare professionals to educate less-educated parents in the management of their children’s/adolescents’ diabetes. Greater financial assistance should be provided to low-income households that may not have access to advanced diabetes treatments.
Chronic hepatitis B virus (HBV) infection is epidemiologically associated with hepatocellular carcinoma (HCC), but its role in HCC remains poorly understood due to technological limitations. In this ...study, we systematically characterize HBV in HCC patients. HBV sequences were enriched from 48 HCC patients using an oligo-bead-based strategy, pooled together and sequenced using the FLX-Genome-Sequencer. In the tumors, preferential integration of HBV into promoters of genes (P < 0.001) and significant enrichment of integration into chromosome 10 (P < 0.01) were observed. Integration into chromosome 10 was significantly associated with poorly differentiated tumors (P < 0.05). Notably, in the tumors, recurrent integration into the promoter of the human telomerase reverse transcriptase (TERT) gene was found to correlate with increased TERT expression. The preferred region within the HBV genome involved in integration and viral structural alteration is at the 3'-end of hepatitis B virus X protein (HBx), where viral replication/transcription initiates. Upon integration, the 3'-end of the HBx is often deleted. HBx-human chimeric transcripts, the most common type of chimeric transcripts, can be expressed as chimeric proteins. Sequence variation resulting in non-conservative amino acid substitutions are commonly observed in HBV genome. This study highlights HBV as highly mutable in HCC patients with preferential regions within the host and virus genome for HBV integration/structural alterations.
The orphan nuclear receptor Nurr1 is critical for the development, maintenance and protection of midbrain dopaminergic (mDA) neurons. Here we show that prostaglandin E1 (PGE1) and its dehydrated ...metabolite, PGA1, directly interact with the ligand-binding domain (LBD) of Nurr1 and stimulate its transcriptional function. We also report the crystallographic structure of Nurr1-LBD bound to PGA1 at 2.05 Å resolution. PGA1 couples covalently to Nurr1-LBD by forming a Michael adduct with Cys566, and induces notable conformational changes, including a 21° shift of the activation function-2 helix (H12) away from the protein core. Furthermore, PGE1/PGA1 exhibit neuroprotective effects in a Nurr1-dependent manner, prominently enhance expression of Nurr1 target genes in mDA neurons and improve motor deficits in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned mouse models of Parkinson's disease. Based on these results, we propose that PGE1/PGA1 represent native ligands of Nurr1 and can exert neuroprotective effects on mDA neurons, via activation of Nurr1's transcriptional function.
For over a half-century the anti-malarial drug chloroquine (CQ) has been used as a therapeutic agent, alone or in combination, to treat autoimmune diseases. However, neither the underlying ...mechanism(s) of action nor their molecular target(s) are well defined. The orphan nuclear receptor Nurr1 (also known as NR4A2) is an essential transcription factor affecting the development and maintenance of midbrain dopaminergic neurons. In this study, using in vitro T cell differentiation models, we demonstrate that CQ activates T
cell differentiation and induces Foxp3 gene expression in a Nurr1-dependent manner. Remarkably, CQ appears to induce Nurr1 function by two distinct mechanisms: firstly, by direct binding to Nurr1's ligand-binding domain and promoting its transcriptional activity and secondly by upregulation of Nurr1 expression through the CREB signaling pathway. In contrast, CQ suppressed gene expression and differentiation of pathogenic T
17 cells. Importantly, using a valid animal model of inflammatory bowel disease (IBD), we demonstrated that CQ promotes Foxp3 expression and differentiation of T
cells in a Nurr1-dependent manner, leading to significant improvement of IBD-related symptoms. Taken together, these data suggest that CQ ameliorates autoimmune diseases via regulating Nurr1 function/expression and that Nurr1 is a promising target for developing effective therapeutics of human inflammatory autoimmune diseases.
Classical Hodgkin lymphoma (cHL) is a clinicopathologically unique, aggressive lymphoma arising from germinal center B-cells and is one of the most curable hematological malignancies. This study ...aimed to determine the clinical course, treatment regimens, response rates, and survival data of patients diagnosed with cHL in a tertiary center.
A retrospective review was conducted to include patients with a diagnosis of cHL from 2013 to 2017. Data of demographic and clinical characteristics, treatment regimens, and outcomes were collected and analyzed.
We recruited 94 patients with a median age of 27.0 interquartile range (IQR), 12 years. Most of the patients were male (61.7%) and 73.4% were ethnic Malay. Nodular sclerosis was the most common histology (77.6%), followed by mixed cellularity (6.4%) and others (16%). The median follow-up time was 28.0 (IQR, 32) months. All patients received chemotherapy but only 13.8% received radiotherapy as consolidation. The doxorubicin-bleomycin-vinblastine-dacarbazine regimen was the most common (85.1%), followed by the escalated bleomycin-etoposide-doxorubicin-cyclophosphamide-vincristineprednisolone-procarbazine regimen (14.9%). Following treatment, 76.1% of patients achieved complete response. The 2-year overall survival (OS) and progression-free survival (PFS) of the entire cohort were 96.5% and 71.1%, respectively. The 2-year OS and PFS for advanced-stage disease were 93.9% and 62.8%, compared to 100% and 82.7% for early-stage disease, respectively (
=0.252 and
=0.052, respectively).
This study provides insight into the clinical presentation and treatment outcomes among patients with cHL in Malaysia. A longer study duration is required to identify OS and PFS benefits and treatment-related complications for different chemotherapeutic regimens.
Patient-derived glioma-propagating cells (GPC) contain karyotypic and gene expression profiles that are found in the primary tumor. However, their clinical relevance is unclear. We ask whether GPCs ...contribute to disease progression and survival outcome in patients with glioma by analyzing gene expression profiles.
We tapped into public sources of GPC gene expression data and derived a gene signature distinguishing oligodendroglial from glioblastoma multiforme (GBM) GPCs. By adapting a method in glioma biology, the Connectivity Map, we interrogated its strength of association in public clinical databases. We validated the top-ranking signaling pathways Wnt, Notch, and TGFβ, in GPCs and primary tumor specimens.
We observed that patients with better prognosis correlated with oligodendroglial GPC features and lower tumor grade, and this was independent of the current clinical indicator, 1p/19q status. Patients with better prognosis had proneural tumors whereas the poorly surviving cohort had mesenchymal tumors. In addition, oligodendroglial GPCs were more sensitive to Wnt and Notch inhibition whereas GBM GPCs responded to TGFβR1 inhibition.
We provide evidence that GPCs are clinically relevant. In addition, the more favorable prognosis of oligodendroglial tumors over GBM could be recapitulated transcriptomically at the GPC level, underscoring the relevance of this cellular model. Our gene signature detects molecular heterogeneity in oligodendroglial tumors that cannot be accounted for by the 1p/19q status alone, indicating that stem-like traits contribute to clinical status. Collectively, these data highlight the limitation of morphology-based histologic analyses in tumor classification, consequently impacting on treatment decisions.
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