Publications by authors named "Bittolo T"

Circulating tumor DNA (ctDNA) levels can help predict outcomes in diffuse large B-cell lymphoma (DLBCL), but its integration with DLBCL molecular clusters remains unexplored. Using the LymphGen tool in 77 DLBCL with both ctDNA and tissue biopsy, a 95.8% concordance rate in molecular cluster assignment was observed, showing the reproducibility of molecular clustering on ctDNA.

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The mutational status of immunoglobulin (IG) light chain genes in chronic lymphocytic leukemia (CLL) and its clinical impact have not been extensively studied. To assess their prognostic significance, the IG light chain gene repertoire in CLL patients has been evaluated using a training-validation approach. In the training cohort (N = 573 CLL), 92.

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In chronic lymphocytic leukemia (CLL), survival of neoplastic cells depends on microenvironmental signals at lymphoid sites where the crosstalk between the integrin VLA-4 (CD49d/CD29), expressed in ~40% of CLL, and the B-cell receptor (BCR) occurs. Here, BCR engagement inside-out activates VLA-4, thus enhancing VLA-4-mediated adhesion of CLL cells, which in turn obtain pro-survival signals from the surrounding microenvironment. We report that the BCR is also able to effectively inside-out activate the VLA-4 integrin in circulating CD49d-expressing CLL cells through an autonomous antigen-independent BCR signaling.

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The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib represents an effective strategy for treatment of chronic lymphocytic leukemia (CLL), nevertheless about 30% of patients eventually undergo disease progression. Here we investigated by flow cytometry the long-term modulation of the CLL CXCR4/CD5 proliferative fraction (PF), its correlation with therapeutic outcome and emergence of ibrutinib resistance. By longitudinal tracking, the PF, initially suppressed by ibrutinib, reappeared upon early disease progression, without association with lymphocyte count or serum beta-2-microglobulin.

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Article Synopsis
  • Scientists studied a type of blood cancer called chronic lymphocytic leukaemia (CLL) that has a mutation in a gene named XPO1.
  • They found that this mutation changes how certain genes are turned on or off, making the cancer cells react more strongly to signals that help them grow.
  • The researchers also discovered that having this mutation is linked to patients needing treatment sooner, which means it could be an important sign of how serious their condition is.
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We investigated 23 hepatitis C virus (HCV)-infected patients with overt lymphoproliferative diseases (15 cases) or monoclonal B lymphocytosis (8 cases) treated with direct agent antiviral (DAAs) per clinical practice. DAA therapy yielded undetectable HCV-RNA, the complete response of cryoglobulinemia vasculitis and related signs, whilst the presence of B-cell clones (evaluated by flow cytometry, IGHV, and BCL2-IGH rearrangements), detected in 19/23 cases at baseline, was maintained (17/19). Similarly, IGHV intraclonal diversification, supporting an antigen-driven selection mechanism, was identified in B-cell clones at baseline and end of follow-up.

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Introduction: MicroRNAs represent interesting targets for new therapies because their altered expression influences tumor development and progression. miR-17 is a prototype of onco-miRNA, known to be overexpressed in B-cell non-Hodgkin lymphoma (B-NHL) with peculiar clinic-biological features. AntagomiR molecules have been largely studied to repress the regulatory functions of up-regulated onco-miRNAs, but their clinical use is mainly limited by their rapid degradation, kidney elimination and poor cellular uptake when injected as naked oligonucleotides.

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The Notch signaling pathway plays a fundamental role for the terminal differentiation of multiple cell types, including B and T lymphocytes. The Notch receptors are transmembrane proteins that, upon ligand engagement, undergo multiple processing steps that ultimately release their intracytoplasmic portion. The activated protein ultimately operates as a nuclear transcriptional co-factor, whose stability is finely regulated.

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mutations account for the most frequent mutations in human cancers, and are generally correlated with disease aggressiveness, poor prognosis, and poor response to therapies. KRAS is required for adult hematopoiesis and plays a key role in B cell development and mature B cell proliferation and survival, proved to be critical for B cell receptor-induced ERK pathway activation. In mature B cell neoplasms, commonly seen in adults, KRAS and RAS-MAPK pathway aberrations occur in a relevant fraction of patients, reaching high recurrence in some specific subtypes like multiple myeloma and hairy cell leukemia.

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Article Synopsis
  • In chronic lymphocytic leukemia (CLL), subclonal mutations below 10% to 15% variant allele frequency (VAF) have unclear clinical implications, but this study investigates their effect on patient survival and response to treatment.
  • A comprehensive analysis of clinical features and mutation frequencies was conducted on two cohorts, with findings indicating that both high and low-VAF mutations were associated with significantly reduced overall survival compared to wild-type patients.
  • The inclusion of low-VAF mutations provided better prognostic risk stratification in CLL than traditional models, suggesting a need to redefine what constitutes mutated CLL for improved clinical practice.
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Chronic lymphocytic leukemia (CLL) is characterized by a low CD20 expression, in part explained by an epigenetic-driven downregulation triggered by mutations of the NOTCH1 gene. In the present study, by taking advantage of a wide and well-characterized CLL cohort (n=537), we demonstrate that CD20 expression is downregulated in SF3B1-mutated CLL in an extent similar to NOTCH1-mutated CLL. In fact, SF3B1-mutated CLL cells show common features with NOTCH1-mutated CLL cells, including a gene expression profile enriched of NOTCH1-related gene sets and elevated expression of the active intracytoplasmic NOTCH1.

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The prognosis of chronic lymphocytic leukemia (CLL) depends on different markers, including cytogenetic aberrations, oncogenic mutations, and mutational status of the immunoglobulin (Ig) heavy-chain variable (IGHV) gene. The number of IGHV mutations distinguishes mutated (M) CLL with a markedly superior prognosis from unmutated (UM) CLL cases. In addition, B cell antigen receptor (BCR) stereotypes as defined by IGHV usage and complementarity-determining regions (CDRs) classify ∼30% of CLL cases into prognostically important subsets.

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CD49d is a remarkable prognostic biomarker of chronic lymphocytic leukemia (CLL). The cutoff value for the extensively validated 30% of positive CLL cells is able to separate CLL patients into 2 subgroups with different prognoses, but it does not consider the pattern of CD49d expression. In the present study, we analyzed a cohort of 1630 CLL samples and identified the presence of ∼20% of CLL cases (n = 313) characterized by a bimodal expression of CD49d, that is, concomitant presence of a CD49d+ subpopulation and a CD49d- subpopulation.

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In chronic lymphocytic leukemia (CLL), stabilizing mutations of NOTCH1, affecting up to 10-15% of cases, have been associated to poor prognosis, disease progression and refractoriness to chemotherapy. NOTCH1 mutations are significantly overrepresented in trisomy 12 CLL, a disease subset frequently expressing CD49d, the α4 chain of the very-late-activation-4 integrin, a well-known key regulator of microenviromental interactions, and negative prognosticator in CLL. In the present study, by analysing a wide cohort of 1180 CLL, we observed a very strong association between the presence of NOTCH1 mutations and the expression of CD49d (P<0.

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In chronic lymphocytic leukemia (CLL), the mechanisms controlling cell growth and proliferation in the presence of NOTCH1 mutations remain largely unexplored. By performing a gene expression profile of NOTCH1-mutated (NOTCH1-mut) versus NOTCH1 wild-type CLL, we identified a gene signature of NOTCH1-mut CLL characterized by the upregulation of genes related to ribosome biogenesis, such as nucleophosmin 1 (NPM1) and ribosomal proteins (RNPs). Activation of NOTCH1 signaling by ethylenediaminetetraacetic acid or by coculture with JAGGED1-expressing stromal cells increased NPM1 expression, and inhibition of NOTCH1 signaling by either NOTCH1-specific small interfering RNA (siRNA) or γ-secretase inhibitor reduced NPM1 expression.

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Venetoclax (ABT-199) is a small-molecule selective oral inhibitor of the antiapoptotic protein Bcl-2 that promotes programmed cell death of chronic lymphocytic leukemia (CLL) cells regulating the release of proapoptotic factors, such as Smac/Diablo, apoptosis-inducing factor (AIF) and cytochrome c. In April 2016, the U.S.

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CD49d, the alpha-chain of the integrin heterodimer α4β1, was identified among the strongest predictors of overall survival (OS) in chronic lymphocytic leukemia (CLL), along with IGHV mutational status and deletion of the 17p chromosome involving TP53. In addition to TP53, the clinical relevance of NOTCH1, SF3B1 and BIRC3 gene mutations has been recently emphasized. By analyzing a cohort of 778 unselected CLL patients, we assessed the clinical relevance of CD49d as an OS predictor in subgroups defined by mutation/deletion of the TP53, NOTCH1, SF3B1 and BIRC3 genes.

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