59 research outputs found

    Banco Tensore d'Inerzia

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    Nella presente relazione si descrive il Banco Tensore d'Inerzia realizzato presso il Dipartimento al fine di soddisfare la richiesta, avanzata in particolar modo dalle aziende del settore automotive, di disporre della misura dei parametri d'inerzia di interi veicoli o di suoi componenti. Dopo aver descritto il principio di funzionamento, si illustreranno le procedure di prova e le tecniche adottate per la calibrazione

    Loss of the candidate tumor suppressor ZEB1 (TCF8, ZFHX1A) in Sézary syndrome

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    Cutaneous T-cell lymphoma is a group of incurable extranodal non-Hodgkin lymphomas that develop from the skin-homing CD4+ T cell. Mycosis fungoides and Sézary syndrome are the most common histological subtypes. Although next-generation sequencing data provided significant advances in the comprehension of the genetic basis of this lymphoma, there is not uniform consensus on the identity and prevalence of putative driver genes for this heterogeneous group of tumors. Additional studies may increase the knowledge about the complex genetic etiology characterizing this lymphoma. We used SNP6 arrays and GISTIC algorithm to prioritize a list of focal somatic copy-number alterations in a dataset of multiple sequential samples from 21 Sézary syndrome patients. Our results confirmed a prevalence of significant focal deletions over amplifications: single well-known tumor suppressors, such as TP53, PTEN, and RB1, are targeted by these aberrations. In our cohort, ZEB1 (TCF8, ZFHX1A) spans a deletion having the highest level of significance. In a larger group of 43 patients, we found that ZEB1 is affected by deletions and somatic inactivating mutations in 46.5% of cases; also, we found potentially relevant ZEB1 germline variants. The survival analysis shows a worse clinical course for patients with ZEB1 biallelic inactivation. Multiple abnormal expression signatures were found associated with ZEB1 depletion in Sézary patients we verified that ZEB1 exerts a role in oxidative response of Sézary cells. Our data confirm the importance of deletions in the pathogenesis of cutaneous T-cell lymphoma. The characterization of ZEB1 abnormalities in Sézary syndrome fulfils the criteria of a canonical tumor suppressor gene. Although additional confirmations are needed, our findings suggest, for the first time, that ZEB1 germline variants might contribute to the risk of developing this disease. Also, we provide evidence that ZEB1 activity in Sézary cells, influencing the reactive oxygen species production, affects cell viability and apoptosis

    Sézary Syndrome, recent biomarkers and new drugs.

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    Sezary syndrome (SS) is a primary cutaneous T-cell lymphoma (CTCL) characterized by erythroderma, lymphadenopathy and leukemic involvement of the peripheral blood. The high relapse rates and a poor prognosis complicate its clinical course and treatment. The phenotypic characterization and genomic/transcriptomic approaches revealed high heterogeneity of Sezary cells, identifying a wide spectrum of biomarkers implicated in the development of this lymphoma. In this context, we discuss the major malignancy-related biomarkers reported in the literature for the diagnosis, prognosis and staging of SS. The hope for a single reliable diagnostic marker appears increasingly unrealistic, but the discovery of multiple potential biomarkers, with pathogenetic implications, paves the road to promising personalized therapies in SS

    Hepatitis C Virus Drives the Unconstrained Monoclonal Expansion of VH1–69-Expressing Memory B Cells in Type II Cryoglobulinemia: A Model of Infection-Driven Lymphomagenesis

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    AbstractChronic hepatitis C virus infection causes B cell lymphoproliferative disorders that include type II mixed cryoglobulinemia and lymphoma. This virus drives the monoclonal expansion and, occasionally, the malignant transformation of B cells producing a polyreactive natural Ab commonly encoded by the VH1–69 variable gene. Owing to their property of producing natural Ab, these cells are reminiscent of murine B-1 and marginal zone B cells. We used anti-Id Abs to track the stages of differentiation and clonal expansion of VH1–69+ cells in patients with type II mixed cryoglobulinemia. By immunophenotyping and cell size analysis, we could define three discrete stages of differentiation of VH1–69+ B cells: naive (small, IgMhighIgDhighCD38+CD27−CD21highCD95−CD5−), "early memory" (medium-sized, IgMhighIgDlowCD38−CD27+CD21lowCD95+CD5+), and "late memory" (large-sized, IgMlowIgDlow-negCD38−CD27lowCD21low-negCD5−CD95−). The B cells expanded in cryoglobulinemia patients have a "memory" phenotype; this fact, together with the evidence for intraclonal variation, suggests that antigenic stimulation by hepatitis C virus causes the unconstrained expansion of activated VH1–69+ B cells. In some cases, these cells replace the entire pool of circulating B cells, although the absolute B cell number remains within normal limits. Absolute monoclonal VH1–69+ B lymphocytosis was seen in three patients with cryoglobulinemia and splenic lymphoma; in two of these patients, expanded cells carried trisomy 3q. The data presented here indicate that the hepatitis C virus-driven clonal expansion of memory B cells producing a VH1–69+ natural Ab escapes control mechanisms and subverts B cell homeostasis. Genetic alterations may provide a further growth advantage leading to an overt lymphoproliferative disorder

    Blood and skin-derived Sezary cells: differences in proliferation-index, activation of PI3K/AKT/mTORC1 pathway and its prognostic relevance

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    Sézary syndrome (SS) is a rare and aggressive variant of Cutaneous T-Cell Lymphoma characterized by neoplastic distribution mainly involving blood, skin, and lymph-node. Although a role of the skin microenvironment in SS pathogenesis has long been hypothesized, its function in vivo is poorly characterized. To deepen this aspect, here we compared skin to blood-derived SS cells concurrently obtained from SS patients highlighting a greater proliferation-index and a PI3K/AKT/mTORC1 pathway activation level, particularly of mTOR protein, in skin-derived-SS cells. We proved that SDF-1 and CCL21 chemokines, both overexpressed in SS tissues, induce mTORC1 signaling activation, cell proliferation and Ki67 up-regulation in a SS-derived cell line and primary-SS cells. In a cohort of 43 SS cases, we observed recurrent copy number variations (CNV) of members belonging to this cascade, namely: loss of LKB1 (48%), PTEN (39%) and PDCD4 (35%) and gains of P70S6K (30%). These alterations represent druggable targets unraveling new therapeutic treatments as metformin here evaluated in vitro. Moreover, CNV of PTEN, PDCD4, and P70S6K, evaluated individually or in combination, are associated with reduced survival of SS patients. These data shed light on effects in vivo of skin-SS cells interaction underlying the prognostic and therapeutic relevance of mTORC1 pathway in SS

    Detection rate for significant cancer at confirmatory biopsy in men enrolled in Active Surveillance protocol: 20 cores vs 30 cores vs MRI/TRUS fusion prostate biopsy

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    Introduction: The detection rate for significant prostate cancer of extended vs saturation vs mMRI/TRUS fusion biopsy was prospectively evaluated in men enrolled in active surveillance (AS) protocol. Mterials and methods: From May 2013 to September 2016 75 men aged 66 years (median) with very low risk PCa were enrolled in an AS protocol and elegible criteria were: life expectancy greater than 10 years, cT1C, PSA below 10 ng/ml, PSA density < 0.20, 2 < unilateral positive biopsy cores, Gleason score (GS) equal to 6, greatest percentage of cancer (GPC) in a core < 50%. All patients underwent 3.0 Tesla pelvic mpMRI before confirmatory transperineal extended (20 cores) or saturation biopsy (SPBx; 30 cores) combined with mpMRI/TRUS fusion targeted biopsy (4 cores) of suspicious lesions (PI-RADS 3-5). Results: 21/75 (28%) patients were reclassified by SPBx based on upgraded GS ≥ 7; mpMRI lesions PI-RADS 4-5 vs PI-RADS 3-5 diagnosed 9/21 (42.8%) vs 16/21 (76.2%) significant PCa with 2 false positives (6.5%). The detection rate for significant PCa was equal to 76.2% (mpMRI/TRUS fusion biopsy) vs 81% (extended) vs 100% (SPBx) (p = 0.001); mpMRI/TRUS targeted biopsy and extended biopsy missed 5/21 (23.8%) and 4/21 (19%) significant PCa which were found by SPBx (p = 0.001) being characterised by the presence of a single positive core of GS ≥ 7 with GPC < 10%. Conclusions: Although mpMRI improve the diagnosis of clinically significant PCa, SPBx is provided of the best detection rate for PCa in men enrolled in AS protocols who underwent confirmatory biopsy

    miR-181b as a therapeutic agent for chronic lymphocytic leukemia in the Eμ-TCL1 mouse model

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    The involvement of microRNAs (miRNAs) in chronic lymphocytic leukemia (CLL) pathogenesis suggests the possibility of anti-CLL therapeutic approaches based on miRNAs. Here, we used the Eµ-TCL1 transgenic mouse model, which reproduces leukemia with a similar course and distinct immunophenotype as human B-CLL, to test miR-181b as a therapeutic agent.In vitro enforced expression of miR-181b mimics induced significant apoptotic effects in human B-cell lines (RAJI, EHEB), as well as in mouse Eµ-TCL1 leukemic splenocytes. Molecular analyses revealed that miR-181b not only affected the expression of TCL1, Bcl2 and Mcl1 anti-apoptotic proteins, but also reduced the levels of Akt and phospho-Erk1/2. Notably, a siRNA anti-TCL1 could similarly down-modulate TCL1, but exhibited a reduced or absent activity in other relevant proteins, as well as a reduced effect on cell apoptosis and viability. In vivo studies demonstrated the capability of miR-181b to reduce leukemic cell expansion and to increase survival of treated mice.These data indicate that miR-181b exerts a broad range of actions, affecting proliferative, survival and apoptotic pathways, both in mice and human cells, and can potentially be used to reduce expansion of B-CLL leukemic cells

    Compatible solutes from hyperthermophiles improve the quality of DNA microarrays

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    <p>Abstract</p> <p>Background</p> <p>DNA microarrays are among the most widely used technical platforms for DNA and RNA studies, and issues related to microarrays sensitivity and specificity are therefore of general importance in life sciences. Compatible solutes are derived from hyperthermophilic microorganisms and allow such microorganisms to survive in environmental and stressful conditions. Compatible solutes show stabilization effects towards biological macromolecules, including DNA.</p> <p>Results</p> <p>We report here that compatible solutes from hyperthermophiles increased the performance of the hybridization buffer for Affymetrix GeneChip<sup>® </sup>arrays. The experimental setup included independent hybridizations with constant RNA over a wide range of compatible solute concentrations. The dependence of array quality and compatible solute was assessed using specialized statistical tools provided by both the proprietary Affymetrix quality control system and the open source Bioconductor suite.</p> <p>Conclusion</p> <p>Low concentration (10 to 25 mM) of hydroxyectoine, potassium mannosylglycerate and potassium diglycerol phosphate in hybridization buffer positively affected hybridization parameters and enhanced microarrays outcome. This finding harbours a strong potential for the improvement of DNA microarray experiments.</p

    Skin homing of Sézary cells involves SDF-1-CXCR4 signaling and down-regulation of CD26/dipeptidylpeptidase IV

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    AbstractSézary syndrome (SS) is a rare form of cutaneous T-cell lymphoma (CTCL) characterized by a distinct metastatic pattern mainly involving blood and skin. Chemokines and their receptors play a critical role in cellular recruitment and homing to tissues and in the metastatic process of several tumors including non-Hodgkin T-cell lymphomas (NHLs). Here we report that SS cells express a functionally active CXCR4 and that its ligand SDF-1 is abundantly produced in the skin, which represents the main destination of SS cell spreading. SDF-1 is normally inactivated by proteolytic cleavage by the CD26/dipeptidylpeptidase IV (DPPIV). The lack of CD26 from the cell surface is a hallmark of circulating SS cells. We also show that the CD26- phenotype is maintained also in skin-infiltrating neoplastic T lymphocytes and that SS-affected individuals exhibit a reduced activity of plasma soluble CD26. Finally, we observe that the addition of soluble CD26 reduces the migratory response of SS cells to SDF-1 whereas the inhibition of the CD26 peptidase activity in Hut78, a CD26+ CTCL cell line, enhances the SDF-1-induced migration of these cells. Our findings suggest that the SDF-1-CXCR4 axis could play an important role in skin homing of SS through the regulatory activity of CD26

    The Interplay between CD27dull and CD27bright B Cells Ensures the Flexibility, Stability, and Resilience of Human B Cell Memory

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    Summary: Memory B cells (MBCs) epitomize the adaptation of the immune system to the environment. We identify two MBC subsets in peripheral blood, CD27dull and CD27bright MBCs, whose frequency changes with age. Heavy chain variable region (VH) usage, somatic mutation frequency replacement-to-silent ratio, and CDR3 property changes, reflecting consecutive selection of highly antigen-specific, low cross-reactive antibody variants, all demonstrate that CD27dull and CD27bright MBCs represent sequential MBC developmental stages, and stringent antigen-driven pressure selects CD27dull into the CD27bright MBC pool. Dynamics of human MBCs are exploited in pregnancy, when 50% of maternal MBCs are lost and CD27dull MBCs transit to the more differentiated CD27bright stage. In the postpartum period, the maternal MBC pool is replenished by the expansion of persistent CD27dull clones. Thus, the stability and flexibility of human B cell memory is ensured by CD27dull MBCs that expand and differentiate in response to change. : Grimsholm et al. show that CD27dull and CD27bright represent sequential MBC developmental stages. T cell- and germinal center (GC)-independent CD27dull MBCs are the plastic source of strongly selected and GC-dependent CD27bright MBCs. CD27dull MBCs, able to expand and differentiate in response to change, ensure stability and flexibility of human B cell memory. Keywords: memory B cells, pregnancy, immunological memory, CD27, VH repertoire, immunodeficiency, aging, spleen, vaccine, germinal cente
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