72 research outputs found

    EGFR positive feedback loops and βeta Catenin driven miR-17-92 cluster converge to regulate EMT and drug resistance

    Get PDF
    Epidermal growth factor receptor (EGFR)-targeted cancer drug represents a mile- stone in oncology. Nevertheless the responses are invariably limited by the emer- gence of secondary drug-resistance (Misale, Di Nicolantonio et al. 2014). We found that drug-treated ‘‘EGFR-addicted’’ cancer cells engage a positive feedback loop lead- ing to NF-KB/βCatenin axis activation (Lauriola, Enuka et al. 2014), consequently promoting cell survival and limiting overall drug response. Specifically, secondary activation of βCatenin drives the production of an oncogenic cluster of microRNAs 17-92 (Lauriola, Donghwa et al. 2015) implicated in EMT transformation and resist- ance in colon clones. Hence βCatenin and EGFR combination pharmacological inhi- bition overcome the colon spheres growth and enhance tumor regression. These findings suggest that inhibition of EGFR feedback loop along with NF-kB/βCatenin axis may increase the response to a broad spectrum of drugs that target pathways of oncogene addiction

    Isolation and characterization of cancer stem cells in head and neck squamous cell carcinoma

    Get PDF
    The hypothesis that a small subset of cells with characteristics of staminality is essential for the cancer onset has been widely studied in many tumors, included head-neck cancer, the seventh most common cancer in humans (1). These cells represent a small oncogenic subpopulation, with a characteristic phenotype that confers them a greater resistance to chemotherapy and radiotherapy (2). In this study the expression profile of some genes that differentiates cancer stem cells (CSC) from tumor cell of origin (TC) has been evaluated using Real Time PCR. Three cell lines, PE46, PE15 and HEP2, obtained from head and neck squamous cell carcinoma, where placed in culture, in absence of serum and in the presence of specific growth factors, giving rise to a spheroid cell subpopulation, with characteristics belonging to CSC. CSC were isolated using a selective filtration procedure based on beads labeled with the anti-CD44, that recognize a specific antigen of CSC in head and neck cancer (1). Few genes potentially involved in the onset and progression of oral cancer, were eval- uated in Real Time PCR, in order to compare their expression in CSC respect TC. All the three cell lines showed a common expression profile among the stem cell markers, resulting in an overexpression of the CD44 and ALDH1A in the spheroid population. Many of the investigated tumor markers were highly over-expressed in CSC, like TNFα, a pro-inflammatory factor that inhibits precancerous cell death, TP63, which is associated with an increase in the malignant transformation and a poor prognosis, and S100A4, a pro-inflammatory mediator involved in epithelial-mesenchymal transition of cancer cells. These results suggest the potential role of CSC in the tumor invasiveness. The characterization of CSC may lead to an improvement in the diagnosis and cancer therapy, allowing implementing treatments able to destroy cells which are probably involved in the process of metastasis

    Lipidomics study of mesenchymal stromal cells derived from human placenta

    Get PDF
    The interest for lipid metabolism in the stem cell field has increased in the last few years (1,2,3). Membrane lipidomics embraces many aspects of cell metabolism and the role of lipids is now considered more than merely inert and structural in delimitating the extra- and intra-cellular compartments (4,5). Nevertheless, we are still far from understanding the impact of membrane lipidomics in stemness maintenance and differentiation patterns. The aim of our work was to study membrane lipidomics of mesenchymal stromal cells derived from human placenta and correlate it to specific biological properties, by using chemically- defined tailored lipid supplements (Refeed®). In the experimental study, the cell membranes of freshly isolated mesenchymal stromal cells obtained from human fetal membranes (FM-MSCs) were characterized for fatty acid composition. Then, we investigated cell morphology, viability, proliferation, differentiation and immunomodulation after in-vitro exposure to Refeed® supplements. Control MSCs were cultured without lipid supplementation. Our results showed a significant reduction of membrane fluidity for in-vitro primary cells, with cell membrane fatty acid composition greatly differing from the in-vivo one. By tailoring lipid supplementation, the fatty acid composition and biophysical properties of in-vitro cell membranes resulted more similar to the in-vivo counterparts, with higher omega-6 fatty acid content and increased membrane fluidity. These modifications of membrane composition and properties had no effect on cell morphology and viability, whereas ameliorated cell proliferation rate, diffentiation ability and immunomodulatory properties. In particular, supplemented FMMSCs showed an increased expression of cell membrane molecules like Vascular Endothelial Growth Factor Receptors 1 (VEGFR-1 or Flt-1) and 2 (VEGFR-2 or KDR), that correlated with a more efficient response to angiogenic commitment. Moreover, regarding immunomodulation, supplemented FM-MSCs displayed an increased expression of the tolerogenic cell surface protein HLA-G, that positively influenced the in-vitro cell immunomodulatory ability. Finally, these data suggest that specific lipid supplementation have functional consequences on in-vitro MSC behavior and may influence cell-based therapeutic approaches

    Ancient oral microbiomes support gradual Neolithic dietary shifts towards agriculture

    Get PDF
    The human microbiome has recently become a valuable source of information about host life and health. To date little is known about how it may have evolved during key phases along our history, such as the Neolithic transition towards agriculture. Here, we shed light on the evolution experienced by the oral microbiome during this transition, comparing Palaeolithic hunter-gatherers with Neolithic and Copper Age farmers that populated a same restricted area in Italy. We integrate the analysis of 76 dental calculus oral microbiomes with the dietary information derived from the identification of embedded plant remains. We detect a stronger deviation from the hunter-gatherer microbiome composition in the last part of the Neolithic, while to a lesser extent in the early phases of the transition. Our findings demonstrate that the introduction of agriculture affected host microbiome, supporting the hypothesis of a gradual transition within the investigated populations

    Evaluation of two sets of immunohistochemical and Western blot confirmatory methods in the detection of typical and atypical BSE cases

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Three distinct forms of bovine spongiform encephalopathy (BSE), defined as classical (C-), low (L-) or high (H-) type, have been detected through ongoing active and passive surveillance systems for the disease.</p> <p>The aim of the present study was to compare the ability of two sets of immunohistochemical (IHC) and Western blot (WB) BSE confirmatory protocols to detect C- and atypical (L- and H-type) BSE forms.</p> <p>Obex samples from cases of United States and Italian C-type BSE, a U.S. H-type and an Italian L-type BSE case were tested in parallel using the two IHC sets and WB methods.</p> <p>Results</p> <p>The two IHC techniques proved equivalent in identifying and differentiating between C-type, L-type and H-type BSE. The IHC protocols appeared consistent in the identification of PrP<sup>Sc </sup>distribution and deposition patterns in relation to the BSE type examined. Both IHC methods evidenced three distinct PrP<sup>Sc </sup>phenotypes for each type of BSE: prevailing granular and linear tracts pattern in the C-type; intraglial and intraneuronal deposits in the H-type; plaques in the L-type.</p> <p>Also, the two techniques gave comparable results for PrP<sup>Sc </sup>staining intensity on the C- and L-type BSE samples, whereas a higher amount of intraglial and intraneuronal PrP<sup>Sc </sup>deposition on the H-type BSE case was revealed by the method based on a stronger demasking step.</p> <p>Both WB methods were consistent in identifying classical and atypical BSE forms and in differentiating the specific PrP<sup>Sc </sup>molecular weight and glycoform ratios of each form.</p> <p>Conclusions</p> <p>The study showed that the IHC and WB BSE confirmatory methods were equally able to recognize C-, L- and H-type BSE forms and to discriminate between their different immunohistochemical and molecular phenotypes. Of note is that for the first time one of the two sets of BSE confirmatory protocols proved effective in identifying the L-type BSE form. This finding helps to validate the suitability of the BSE confirmatory tests for BSE surveillance currently in place.</p

    Mitogenomes from Egyptian Cattle Breeds: New Clues on the Origin of Haplogroup Q and the Early Spread of Bos taurus from the Near East

    Get PDF
    Background Genetic studies support the scenario that Bos taurus domestication occurred in the Near East during the Neolithic transition about 10 thousand years (ky) ago, with the likely exception of a minor secondary event in Italy. However, despite the proven effectiveness of whole mitochondrial genome data in providing valuable information concerning the origin of taurine cattle, until now no population surveys have been carried out at the level of mitogenomes in local breeds from the Near East or surrounding areas. Egypt is in close geographic and cultural proximity to the Near East, in particular the Nile Delta region, and was one of the first neighboring areas to adopt the Neolithic package. Thus, a survey of mitogenome variation of autochthonous taurine breeds from the Nile Delta region might provide new insights on the early spread of cattle rearing outside the Near East. Methodology Using Illumina high-throughput sequencing we characterized the mitogenomes from two cattle breeds, Menofi (N = 17) and Domiaty (N = 14), from the Nile Delta region. Phylogenetic and Bayesian analyses were subsequently performed. Conclusions Phylogenetic analyses of the 31 mitogenomes confirmed the prevalence of haplogroup T1, similar to most African cattle breeds, but showed also high frequencies for haplogroups T2, T3 and Q1, and an extremely high haplotype diversity, while Bayesian skyline plots pointed to a main episode of population growth ~12.5 ky ago. Comparisons of Nile Delta mitogenomes with those from other geographic areas revealed that (i) most Egyptian mtDNAs are probably direct local derivatives from the founder domestic herds which first arrived from the Near East and the extent of gene flow from and towards the Nile Delta region was limited after the initial founding event(s); (ii) haplogroup Q1 was among these founders, thus proving that it underwent domestication in the Near East together with the founders of the T clades
    corecore