78 research outputs found
Model of fibrolamellar hepatocellular carcinomas reveals striking enrichment in cancer stem cells
The aetiology of human fibrolamellar hepatocellular carcinomas (hFL-HCCs), cancers occurring increasingly in children to young adults, is poorly understood. We present a transplantable tumour line, maintained in immune-compromised mice, and validate it as a bona fide model of hFL-HCCs by multiple methods. RNA-seq analysis confirms the presence of a fusion transcript (DNAJB1-PRKACA) characteristic of hFL-HCC tumours. The hFL-HCC tumour line is highly enriched for cancer stem cells as indicated by limited dilution tumourigenicity assays, spheroid formation and flow cytometry. Immunohistochemistry on the hFL-HCC model, with parallel studies on 27 primary hFL-HCC tumours, provides robust evidence for expression of endodermal stem cell traits. Transcriptomic analyses of the tumour line and of multiple, normal hepatic lineage stages reveal a gene signature for hFL-HCCs closely resembling that of biliary tree stem cells-newly discovered precursors for liver and pancreas. This model offers unprecedented opportunities to investigate mechanisms underlying hFL-HCCs pathogenesis and potential therapies
Enhanced Expression of Human Endogenous Retroviruses, TRIM28 and SETDB1 in Autism Spectrum Disorder
Human endogenous retroviruses (HERVs) are relics of ancestral infections and represent 8% of the human genome. They are no longer infectious, but their activation has been associated with several disorders, including neuropsychiatric conditions. Enhanced expression of HERV-K and HERV-H envelope genes has been found in the blood of autism spectrum disorder (ASD) patients, but no information is available on syncytin 1 (SYN1), SYN2, and multiple sclerosis-associated retrovirus (MSRV), which are thought to be implicated in brain development and immune responses. HERV activation is regulated by TRIM28 and SETDB1, which are part of the epigenetic mechanisms that organize the chromatin architecture in response to external stimuli and are involved in neural cell differentiation and brain inflammation. We assessed, through a PCR realtime Taqman amplification assay, the transcription levels of pol genes of HERV-H, -K, and -W families, of env genes of SYN1, SYN2, and MSRV, as well as of TRIM28 and SETDB1 in the blood of 33 ASD children (28 males, median 3.8 years, 25–75% interquartile range 3.0–6.0 y) and healthy controls (HC). Significantly higher expressions of TRIM28 and SETDB1, as well as of all the HERV genes tested, except for HERV-W-pol, were found in ASD, as compared with HC. Positive correlations were observed between the mRNA levels of TRIM28 or SETDB1 and every HERV gene in ASD patients, but not in HC. Overexpression of TRIM28/SETDB1 and several HERVs in children with ASD and the positive correlations between their transcriptional levels suggest that these may be main players in pathogenetic mechanisms leading to ASD
First diagnosis of multisystem inflammatory syndrome in children (MIS-C): an analysis of PoCUS findings in the ED
Children with multisystem inflammatory syndrome (MIS-C) tend to develop a clinical condition of fluid overload due both to contractile cardiac pump deficit and to endotheliitis with subsequent capillary leak syndrome. In this context, the ability of point-of-care ultrasound (PoCUS) to simultaneously explore multiple systems and detect polyserositis could promote adequate therapeutic management of fluid balance. We describe the PoCUS findings in a case-series of MIS-C patients admitted to the Emergency Department. At admission 10/11 patients showed satisfactory clinical condition without signs and symptoms suggestive for cardiovascular impairment/shock, but PoCUS showed pathological findings in 11/11 (100%). In particular, according to Rapid Ultrasound in SHock (RUSH) protocol, cardiac hypokinesis was detected in 5/11 (45%) and inferior vena cava dilatation in 3/11 (27%). Peritoneal fluid was reported in 6/11 cases (54%). Lung ultrasound (LUS) evaluation revealed an interstitial syndrome in 11/11 (100%), mainly localized in posterior basal lung segments. We suggest PoCUS as a useful tool in the first evaluation of children with suspected MIS-C for the initial therapeutic management and the following monitoring of possible cardiovascular deterioration
Activation of anti-apoptotic machinery downstream to Fas/FasL pathway in primary mixed and pure mucin producing cholangiocarcinoma cells: key role of c-FLIP
Cholangiocarcinoma (CCA) comprises a heterogeneous group of malignancies lacking of effective strategies for prevention and cure. Recently, we have established a protocol for the isolation of primary cells from mixed and mucin specimens of human CCA. To this regard, the aim of this study was to analyze the influence on proliferation and apoptosis as well as the related modifications of apoptotic machinery downstream to Fas/FasL pathway in primary cultures of human mixed and mucin-producing CCA after direct co-culture with peripheral blood mononuclear cells (PBMCs). Our findings show that both IH-CCA subtypes constitutively express high levels of Fas and FasL. Following direct co-culture with PBMCs, the expression of Fas and FasL significantly increased after 24, 48 and 72 hours of exposure (p< 0.05). At the same time, a significant increase of percentage of apoptotic CD4+ and CD8+ T-cells or Natural Killer CD56+ cells was observed along the co-cultures compared to PBMCs cultured alone (
Toll-like receptor-4 expression by hepatic progenitor cells and biliary epithelial cells in HCV-related chronic liver disease
Background. Toll-like receptor-4 (TLR4) is a transmembrane pattern recognition receptor that plays a key role in innate immunity by triggering inflammatory responses to Gram negative bacteria lipopolysaccharide (LPS) (1). Since liver is the main clearance organ for LPS, which is excreted in large amounts in the bile (2), it is not surprising that TLR4 has been involved in the pathogenesis of most liver diseases (3). Numerous evidences suggest a role for TLR4 in the pathogenesis of chronic hepatitis C virus (HCV) infection (4) and hepatic fibrosis (5), but the localization and level of TLR4 expression in the liver of patients with hepatitis C have never been investigated. Aim and methods. We aimed to evaluate, by means of immunohistochemistry (IHC) and real-time polymerase chain reaction (rt-PCR), hepatic TLR4 expression in patients with chronic HCV infection. Sixty-one patients with chronic HCV infection, and 12 controls free of liver disease, were included in the study. Each case was analyzed by IHC for TLR4, α–smooth muscle actin (αSMA) and cytokeratin-7 (CK-7), and a subgroup of patients and all controls by rt-PCR for TLR4. A score of activation of portal/septal myofibroblasts and lobular hepatic stellate cells (HSCs) was evaluated by IHC for α-SMA, whereas IHC for CK-7 was analysed in order to count hepatic progenitor cells (HPCs), interlobular bile ducts and intermediate hepatocytes. Results. The parenchimal elements responsible for the highest TLR4 level of expression were HPCs and biliary epithelial cells (BECs) of interlobular bile ducts in the infected group. Double-labeling experiments with anti-TLR4, anti-CK7 and anti-CD133 confirmed this finding. TLR4-positive HPCs and interlobular bile ducts were significantly correlated with the stage of liver disease (p<0.001), the grade of inflammation (p<0.001), and with the activity of portal/septal myofibroblasts (p<0.001). Rt-PCR study confirmed an increased TLR4 expression in the 26 patients analyzed with respect to controls (p<0.001). TLR4 expression positively correlated with fibrosis (p<0.05) and inflammation (p<0.05). Conclusions. The expression of TLR4 in HPCs and BECs in HCV-related liver damage significantly correlates with inflammation, activation of portal/septal myofibroblasts and fibrosis. 1) Beutler. Nature 2004;430:257-63; 2) Van Bossuyt et al. J Hepatol 1988;7:325-37; 3) Seki et al. Hepatology 2008;48:322-35; 4) Machida et al. J Virol 2006;80:866-74. 5) Seki et al. Nat Med 2007;13:1324-32
Model of fibrolamellar hepatocellular carcinomas reveals striking enrichment in cancer stem cells
The aetiology of human fibrolamellar hepatocellular carcinomas (hFL-HCCs), cancers occurring increasingly in children to young adults, is poorly understood. We present a transplantable tumour line, maintained in immune-compromised mice, and validate it as a bona fide model of hFL-HCCs by multiple methods. RNA-seq analysis confirms the presence of a fusion transcript (DNAJB1-PRKACA) characteristic of hFL-HCC tumours. The hFL-HCC tumour line is highly enriched for cancer stem cells as indicated by limited dilution tumourigenicity assays, spheroid formation and flow cytometry. Immunohistochemistry on the hFL-HCC model, with parallel studies on 27 primary hFL-HCC tumours, provides robust evidence for expression of endodermal stem cell traits. Transcriptomic analyses of the tumour line and of multiple, normal hepatic lineage stages reveal a gene signature for hFL-HCCs closely resembling that of biliary tree stem cells—newly discovered precursors for liver and pancreas. This model offers unprecedented opportunities to investigate mechanisms underlying hFL-HCCs pathogenesis and potential therapies
Modulation of biliary cancer chemo-resistance through microRNA-mediated rewiring of the expansion of CD133+ cells
Changes in single microRNA (MIR) expression have been associated with chemo-resistance in Biliary Tract Cancer (BTC). However, a global assessment of the dynamic role of the microRNome has never been performed to identify potential therapeutic targets that are functionally relevant in the BTC cell response to chemotherapy. APPROACH AND RESULTS: high-throughput-screening of 997 LNA-MIR-inhibitors was performed in 6 CCA cell lines treated with Cisplatin-Gemcitabine (CG) seeking changes in cell viability. Validation experiments were performed with miRvana probes. MIR and gene expression was assessed by TaqMan-assay, RNA-sequencing and in-situ-hybridization in 4 indepedent cohorts of human BTC. Knock-out of microRNA was achieved by CRISPR-CAS9 in CCLP cells (MIR1249KO) and tested for effects on chemotherapy sensitivity in-vitro and in-vivo. High-throughput-screening revealed that MIR1249-inhibition enhanced chemotherapy sensitivity across all cell lines. MIR1249 expression was increased in 41% of cases in human BTC. In validation experiments, MIR1249-inhibition did not alter cell viability in untreated or DMSO-treated cells; however it did increase CG effect. MIR1249 expression was increased in CD133+ biliary cancer cells freshly isolated from the stem niche of human BTC, as well as in CD133+ chemo-resistant CCLP cells. MIR1249 modulated the chemotherapy-induced enrichment of CD133+ cells by controlling their clonal expansion via the Wnt-regulator FZD8. MIR1249KO cells had impaired expansion of the CD133+ subclone and its enrichment after chemotherapy, reduced expression of Cancer-Stem-Cell markers, and increased chemosensitivity. MIR1249KO xenograft BTC models showed tumour shrinkage after exposure to weekly CG, while WT models showed only stable disease over treatment
Molecular portraits of patients with intrahepatic cholangiocarcinoma who diverge as rapid progressors or long survivors on chemotherapy
OBJECTIVE: Cytotoxic agents are the cornerstone of treatment for patients with advanced intrahepatic cholangiocarcinoma (iCCA), despite heterogeneous benefit. We hypothesised that the pretreatment molecular profiles of diagnostic biopsies can predict patient benefit from chemotherapy and define molecular bases of innate chemoresistance. DESIGN: We identified a cohort of advanced iCCA patients with comparable baseline characteristics who diverged as extreme outliers on chemotherapy (survival 23 m in long survivors, LS). Diagnostic biopsies were characterised by digital pathology, then subjected to whole-transcriptome profiling of bulk and geospatially macrodissected tissue regions. Spatial transcriptomics of tumour-infiltrating myeloid cells was performed using targeted digital spatial profiling (GeoMx). Transcriptome signatures were evaluated in multiple cohorts of resected cancers. Signatures were also characterised using in vitro cell lines, in vivo mouse models and single cell RNA-sequencing data. RESULTS: Pretreatment transcriptome profiles differentiated patients who would become RPs or LSs on chemotherapy. Biologically, this signature originated from altered tumour-myeloid dynamics, implicating tumour-induced immune tolerogenicity with poor response to chemotherapy. The central role of the liver microenviroment was confrmed by the association of the RPLS transcriptome signature with clinical outcome in iCCA but not extrahepatic CCA, and in liver metastasis from colorectal cancer, but not in the matched primary bowel tumours. CONCLUSIONS: The RPLS signature could be a novel metric of chemotherapy outcome in iCCA. Further development and validation of this transcriptomic signature is warranted to develop precision chemotherapy strategies in these settings
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