363 research outputs found
AICAR and compound C negatively modulate HCC-induced primary human hepatic stellate cell activation in vitro
Tumour stroma and microenvironment have been shown to affect hepatocellular carcinoma (HCC) growth, with activated hepatic stellate cells (HSC) as a major contributor in this process. Recent evidence suggests that the energy sensor adenosine monophosphate-activated kinase (AMPK) may mediate a series of essential processes during carcinogenesis and HCC progression. Here, we investigated the effect of different HCC cell lines with known TP53 or CTNBB1 mutations on primary human HSC activation, proliferation and AMPK activation. We show that conditioned media obtained from multiple HCC cell lines differently modulate human hHSC proliferation and hHSC AMPK activity in a paracrine manner. Pharmacological treatment of hHSC with AICAR and Compound C inhibited the HCC-induced proliferation/activation of hHSC through AMPK-dependent and AMPK-independent mechanisms, which was further confirmed using mouse embryonic fibroblasts (MEFs) deficient of both catalytic AMPKα isoforms (AMPKα1/α2-/-) and wild type (wt) MEF. Both compounds induced S-phase cell-cycle arrest and, in addition, AICAR inhibited the mTORC1 pathway by inhibiting phosphorylation of 4E-BP1 and S6 in hHSC and wt MEF. Datamining of the Cancer Genome Atlas (TCGA) and the Liver Cancer (LICA-FR) showed that AMPKα1 (PRKAA1) and AMPKα2 (PRKAA2) expression differed depending on the mutation (TP53 or CTNNB1), tumour grading and G1-G6 classification, reflecting the heterogeneity in human HCC. Overall, we provide evidence that AMPK modulating pharmacological agents negatively modulate HCC-induced hHSC activation and may therefore provide a novel approach to target the mutual, tumour-promoting interactions between hHSC and HCC
Spinal intradural extraosseous Ewing's sarcoma
Extraosseous Ewing's sarcoma (EES) involving the central nervous system is rare, but can be diagnosed and distinguished from other primitive neuroectodermal tumors (PNET) by identification of the chromosomal translocation (11;22)(q24;q12). We report EES arising from the spinal intradural extramedullary space, based on imaging, histopathological, and molecular data in two men, ages 50 and 60 years old and a review of the literature using PubMed (1970–2009). Reverse transcriptase polymerase chain reaction (RT-PCR) identified the fusion product FL1-EWS. Multimodal therapy, including radiation and alternating chemotherapy including vincristine, cyclophosphamide, doxorubicin and ifosfamide and etoposide led to local tumor control and an initial, favorable therapeutic response. No systemic involvement was seen from the time of diagnosis to the time of last follow-up (26 months) or death (4 years). This report confirms that EES is not confined to the earliest decades of life, and like its rare occurrence as an extra-axial meningeal based mass intracranially, can occasionally present as an intradural mass in the spinal canal without evidence of systemic tumor. Gross total resection followed by multimodal therapy may provide for extended progression free and overall survival
Cellular expression, trafficking, and function of two isoforms of human ULBP5/RAET1G
Background:
The activating immunoreceptor NKG2D is expressed on Natural Killer (NK) cells and subsets of T cells. NKG2D contributes to anti-tumour and anti-viral immune responses in vitro and in vivo. The ligands for NKG2D in humans are diverse proteins of the MIC and ULBP/RAET families that are upregulated on the surface of virally infected cells and tumours. Two splicing variants of ULBP5/RAET1G have been cloned previously, but not extensively characterised.
Methodology/Principal Findings:
We pursue a number of approaches to characterise the expression, trafficking, and function of the two isoforms of ULBP5/RAET1G. We show that both transcripts are frequently expressed in cell lines derived from epithelial cancers, and in primary breast cancers. The full-length transcript, RAET1G1, is predicted to encode a molecule with transmembrane and cytoplasmic domains that are unique amongst NKG2D ligands. Using specific anti-RAET1G1 antiserum to stain tissue microarrays we show that RAET1G1 expression is highly restricted in normal tissues. RAET1G1 was expressed at a low level in normal gastrointestinal epithelial cells in a similar pattern to MICA. Both RAET1G1 and MICA showed increased expression in the gut of patients with celiac disease. In contrast to healthy tissues the RAET1G1 antiserum stained a wide variety or different primary tumour sections. Both endogenously expressed and transfected RAET1G1 was mainly found inside the cell, with a minority of the protein reaching the cell surface. Conversely the truncated splicing variant of RAET1G2 was shown to encode a soluble molecule that could be secreted from cells. Secreted RAET1G2 was shown to downregulate NKG2D receptor expression on NK cells and hence may represent a novel tumour immune evasion strategy.
Conclusions/Significance:
We demonstrate that the expression patterns of ULBP5RAET1G are very similar to the well-characterised NKG2D ligand, MICA. However the two isoforms of ULBP5/RAET1G have very different cellular localisations that are likely to reflect unique functionality
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Questioning the “Ease” in disease: Was living with HIV a burden or boost during the first wave of Covid-19 in France? A qualitative study (COVIDHIV)
Introduction
Clinical research has focused on risk factors and treatment for severe acute respiratory syndrome coronavirus 2 (SARS-COV-2), particularly in people with a comorbidity including the human immunodeficiency virus (HIV), but little attention has been paid to the care pathway. This article aims to show how living with HIV may have been a biopsychosocial burden or boost in care pathways for Covid-19.
Method
People living with HIV (PLHIV) from 9 clinical centers were invited to participate in this qualitative study. The sampling was purposive with a maximum variation in their sociodemographic profiles. Semi-structured interviews were conducted until data saturation, then coded for thematic analysis, using an inductive general approach.
Results
We interviewed 34 PLHIV of which 20 had SARS-COV-2 once. They were 24 males, 26 born in France; median age: 55. Twenty had a CD4 number above 500, and all were on antiretroviral therapy (ART). HIV appeared as a burden when Covid-19 symptoms reminded HIV seroconversion, fear of contamination, and triggered questions about ART effectiveness. HIV was not considered relevant when diagnosing Covid-19, caused fear of disclosure when participants sought SARS-COV-2 testing, and its care in hospitals was disrupted by the pandemic. ART-pill fatigue caused avoidance for Covid-19 treatment. As a boost, living with HIV led participants to observe symptoms, to get advice from healthcare professionals, and screening access through them. Some participants could accept the result of screening or a clinical diagnosis out of resilience. Some could consider ART or another drug prescribed by their HIV specialist help them to recover from Covid-19.
Conclusion
Living with HIV could function as a burden and/or a boost in the care pathways for Covid-19, according to patients’ relationship to their HIV history, comorbidities and representation of ART. Covid-19 in PLHIV needs further qualitative study to gain a more comprehensive assessment of the pandemic’s consequences on their lives and coping strategies
Twenty articles that critical care clinicians should read about COVID-19
Infection with the severe acute respiratory syndrome coronavirus-
2 (SARS-CoV-2) was first identified in December
2019 and has since become a worldwide pandemic,
challenging and sometimes overwhelming healthcare
systems as well as causing more than a million deaths
thus far. In just 10 months, over 80,000 indexed publications
have appeared that reference SARS-CoV-2 and the
associated Coronavirus disease 2019 (COVID-19). In this
article, we highlight 20 papers that are of particular relevance
to the critical care clinician. The papers are divided
into four broad topics: manifestations of severe COVID-
19 disease, pharmacological therapy for COVID-19, ventilatory
support for COVID-19 acute respiratory distress
syndrome (ARDS), and healthcare system and worker
stress. This list is not designed to be comprehensive but
rather to give the reader an overview of important early
papers and their findings.info:eu-repo/semantics/publishedVersio
Functional immunomics: Microarray analysis of IgG autoantibody repertoires predicts the future response of NOD mice to an inducer of accelerated diabetes
One's present repertoire of antibodies encodes the history of one's past
immunological experience. Can the present autoantibody repertoire be consulted
to predict resistance or susceptibility to the future development of an
autoimmune disease? Here we developed an antigen microarray chip and used
bioinformatic analysis to study a model of type 1 diabetes developing in
non-obese diabetic (NOD) male mice in which the disease was accelerated and
synchronized by exposing the mice to cyclophosphamide at 4 weeks of age. We
obtained sera from 19 individual mice, treated the mice to induce
cyclophosphamide-accelerated diabetes (CAD), and found, as expected, that 9
mice became severely diabetic while 10 mice permanently resisted diabetes. We
again obtained serum from each mouse afterCAD induction. We then analyzed the
patterns of antibodies in the individualmice to 266 different antigens spotted
on the antigen chip. We identified a select panel of 27 different antigens (10%
of the array) that revealed a pattern of IgG antibody reactivity in the pre-CAD
serathat discriminated between the mice resistant or susceptible to CAD with
100% sensitivity and 82% specificity (p=0.017). Surprisingly, the set of IgG
antibodies that was informative before CAD induction did not separate the
resistant and susceptible groups after the onset of CAD; new antigens became
criticalfor post-CAD repertoire discrimination. Thus, at least for a model
disease, present antibody repertoires can predict future disease; predictive
and diagnostic repertoires can differ; and decisive information about immune
system behavior can be mined by bioinformatic technology. Repertoires matter.Comment: See Advanced Publication on the PNAS website for final versio
Toward understanding and exploiting tumor heterogeneity
The extent of tumor heterogeneity is an emerging theme that researchers are only beginning to understand. How genetic and epigenetic heterogeneity affects tumor evolution and clinical progression is unknown. The precise nature of the environmental factors that influence this heterogeneity is also yet to be characterized. Nature Medicine, Nature Biotechnology and the Volkswagen Foundation organized a meeting focused on identifying the obstacles that need to be overcome to advance translational research in and tumor heterogeneity. Once these key questions were established, the attendees devised potential solutions. Their ideas are presented here
HNF1α inhibition triggers epithelial-mesenchymal transition in human liver cancer cell lines
<p>Abstract</p> <p>Background</p> <p>Hepatocyte Nuclear Factor 1α (HNF1α) is an atypical homeodomain-containing transcription factor that transactivates liver-specific genes including albumin, α-1-antitrypsin and α- and β-fibrinogen. Biallelic inactivating mutations of <it>HNF1A </it>have been frequently identified in hepatocellular adenomas (HCA), rare benign liver tumors usually developed in women under oral contraceptives, and in rare cases of hepatocellular carcinomas developed in non-cirrhotic liver. HNF1α-mutated HCA (H-HCA) are characterized by a marked steatosis and show activation of glycolysis, lipogenesis, translational machinery and mTOR pathway. We studied the consequences of HNF1α silencing in hepatic cell lines, HepG2 and Hep3B and we reproduced most of the deregulations identified in H-HCA.</p> <p>Methods</p> <p>We transfected hepatoma cell lines HepG2 and Hep3B with siRNA targeting HNF1α and obtained a strong inhibition of HNF1α expression. We then looked at the phenotypic changes by microscopy and studied changes in gene expression using qRT-PCR and Western Blot.</p> <p>Results</p> <p>Hepatocytes transfected with HNF1α siRNA underwent severe phenotypic changes with loss of cell-cell contacts and development of migration structures. In HNF1α-inhibited cells, hepatocyte and epithelial markers were diminished and mesenchymal markers were over-expressed. This epithelial-mesenchymal transition (EMT) was related to the up regulation of several EMT transcription factors, in particular <it>SNAIL </it>and <it>SLUG</it>. We also found an overexpression of TGFβ1, an EMT initiator, in both cells transfected with HNF1α siRNA and H-HCA. Moreover, TGFβ1 expression is strongly correlated to HNF1α expression in cell models, suggesting regulation of TGFβ1 expression by HNF1α.</p> <p>Conclusion</p> <p>Our results suggest that HNF1α is not only important for hepatocyte differentiation, but has also a role in the maintenance of epithelial phenotype in hepatocytes.</p
Clear and independent associations of several HLA-DRB1 alleles with differential antibody responses to hepatitis B vaccination in youth
To confirm and refine associations of human leukocyte antigen (HLA) genotypes with variable antibody (Ab) responses to hepatitis B vaccination, we have analyzed 255 HIV-1 seropositive (HIV+) youth and 80 HIV-1 seronegatives (HIV−) enrolled into prospective studies. In univariate analyses that focused on HLA-DRB1, -DQA1, and -DQB1 alleles and haplotypes, the DRB1*03 allele group and DRB1*0701 were negatively associated with the responder phenotype (serum Ab concentration ≥ 10 mIU/mL) (P = 0.026 and 0.043, respectively). Collectively, DRB1*03 and DRB1*0701 were found in 42 (53.8%) out of 78 non-responders (serum Ab <10 mIU/mL), 65 (40.6%) out of 160 medium responders (serum Ab 10–1,000 mIU/mL), and 27 (27.8%) out of 97 high responders (serum Ab >1,000 mIU/mL) (P < 0.001 for trend). Meanwhile, DRB1*08 was positively associated with the responder phenotype (P = 0.010), mostly due to DRB1*0804 (P = 0.008). These immunogenetic relationships were all independent of non-genetic factors, including HIV-1 infection status and immunodeficiency. Alternative analyses confined to HIV+ youth or Hispanic youth led to similar findings. In contrast, analyses of more than 80 non-coding, single nucleotide polymorphisms within and beyond the three HLA class II genes revealed no clear associations. Overall, several HLA-DRB1 alleles were major predictors of differential Ab responses to hepatitis B vaccination in youth, suggesting that T-helper cell-dependent pathways mediated through HLA class II antigen presentation are critical to effective immune response to recombinant vaccines
Gene expression profiling of meningiomas: current status after a decade of microarray-based transcriptomic studies
Purpose This article provides a review of the transcriptomic expression profiling studies that have been performed on meningiomas so far. We discuss some future prospects and challenges ahead in the field of gene expression profiling. Methods We performed a systematic search in the PubMed and EMBASE databases in May 2010 using the following search terms alone or in combination: “meningioma”, “microarray analysis”, “oligonucleotide array sequence analysis”, or “gene expression profiling”. Only original research articles in English that had used RNA hybridized to high-resolution microarray chips to generate gene expression profiles were included. Results We identified 13 articles matching the inclusion criteria. All studies had been performed during the last decade. Conclusions The main results of the studies can be grouped in three categories: (1) several groups have identified meningioma-specific genes and genes associated with the three WHO grades, and the main histological subtypes of grade I meningiomas; (2) one publication has shown that the general transcription profile of samples of all WHO grades differs in vivo and in vitro; (3) one report provides evidence that microarray technology can be used in an automated fashion to classify tumors. Due to lack of consensus on how microarray data are presented, possible general trends found across the studies are difficult to extract. This could obstruct the discovery of important genes and pathways universally involved in meningioma biology
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