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Brunangelo Falini

Publications and source records attributed to Brunangelo Falini.

At least 19 recordsLinked to original sources
PubMed2022

The International Consensus Classification of Mature Lymphoid Neoplasms: a report from the Clinical Advisory Committee.

Since the publication of the Revised European-American Classification of Lymphoid Neoplasms in 1994, subsequent updates of the classification of lymphoid neoplasms have been generated through iterative international efforts to achieve broad consensus among hematopathologists, geneticists, molecular scientists, and clinicians. Significant progress has recently been made in the characterization of malignancies of the immune system, with many new insights provided by genomic studies. They have led to this proposal. We have followed the same process that was successfully used for the third and fourth editions of the World Health Organization Classification of Hematologic Neoplasms. The definition, recommended studies, and criteria for the diagnosis of many entities have been extensively refined. Some categories considered provisional have now been upgraded to definite entities. Terminology for some diseases has been revised to adapt nomenclature to the current knowledge of their biology, but these modifications have been restricted to well-justified situations. Major findings from recent genomic studies have impacted the conceptual framework and diagnostic criteria for many disease entities. These changes will have an impact on optimal clinical management. The conclusions of this work are summarized in this report as the proposed International Consensus Classification of mature lymphoid, histiocytic, and dendritic cell tumors.

Advisory Committees↗
PubMed2006

Acute myeloid leukemia carrying cytoplasmic/mutated nucleophosmin (NPMc+ AML): biologic and clinical features.

The nucleophosmin (NPM1) gene encodes for a multifunctional nucleocytoplasmic shuttling protein that is localized mainly in the nucleolus. NPM1 mutations occur in 50% to 60% of adult acute myeloid leukemia with normal karyotype (AML-NK) and generate NPM mutants that localize aberrantly in the leukemic-cell cytoplasm, hence the term NPM-cytoplasmic positive (NPMc+ AML). Cytoplasmic NPM accumulation is caused by the concerted action of 2 alterations at mutant C-terminus, that is, changes of tryptophan(s) 288 and 290 (or only 290) and creation of an additional nuclear export signal (NES) motif. NPMc+ AML shows increased frequency in adults and females, wide morphologic spectrum, multilineage involvement, high frequency of FLT3-ITD, CD34 negativity, and a distinct gene-expression profile. Analysis of mutated NPM has important clinical and pathologic applications. Immunohistochemical detection of cytoplasmic NPM predicts NPM1 mutations and helps rationalize cytogenetic/molecular studies in AML. NPM1 mutations in absence of FLT3-ITD identify a prognostically favorable subgroup in the heterogeneous AML-NK category. Due to their frequency and stability, NPM1 mutations may become a new tool for monitoring minimal residual disease in AML-NK. Future studies should focus on clarifying how NPM mutants promote leukemia, integrating NPMc+ AML in the upcoming World Health Organization leukemia classification, and eventually developing specific antileukemic drugs.

Active Transport, Cell Nucleus↗
PubMed2006

Mutated nucleophosmin detects clonal multilineage involvement in acute myeloid leukemia: Impact on WHO classification.

Because of a lack of specific clonality markers, information on lineage involvement and cell of origin of acute myeloid leukemia with normal karyotype (AML-NK), is missing. Because Nucleophosmin (NPM) gene is frequently mutated in AML-NK and causes aberrant NPM cytoplasmic localization (NPMc+), it was used as an AML lineage clonality marker. Clonal NPM exon 12 mutations were detected in myeloid, monocytic, erythroid, and megakaryocytic cells but not in fibroblasts or endothelia that were laser-microdissected from 3 patients with NPMc+ AML. Aberrant cytoplasmic expression of mutated NPM proteins was identified with anti-NPM antibodies in 2 or more myeloid hemopoietic cell lineages in 99 (61.5%) of 161 of NPMc+ AML paraffin-embedded bone marrow biopsies; lymphoid involvement was excluded in 3 investigated cases. These findings suggest that NPMc+ AML derives from either a common myeloid or earlier progenitor. Immunohistochemical studies show that varying combinations and ratios of NPMc+ leukemic cells from distinct lineages are responsible for heterogeneity within each French-American-British (FAB) classification type and for NPMc+ AML falling into different FAB categories. These findings question the value of FAB criteria in subdividing the WHO category of "AML not otherwise characterized" and suggest that, for clinical use, NPMc+ AML be provisionally regarded as a separate AML with prognostic significance.

Biomarkers, Tumor↗
PubMed2006

Immunohistochemistry predicts nucleophosmin (NPM) mutations in acute myeloid leukemia.

Nucleophosmin (NPM) exon-12 mutations occur in 50% to 60% of adult acute myeloid leukemia (AML) with normal karyotype and are predictors of favorable prognosis. We evaluated bone marrow or peripheral blood samples from 450 adult patients with AML of the GIMEMA (Gruppo Italiano Malattie Ematologiche Maligne dell'Adulto)/AML12 EORTC (European Organization for Research and Treatment of Cancer) trial to (1) search for new exon-12 NPM mutations; (2) determine whether NPM immunostaining on paraffin-embedded biopsies predicts NPM mutations; and (3) investigate altered nucleocytoplasmic NPM traffic in primary AML cells. Fourteen NPM mutations, including 8 new variants, were identified. All 200 AML cases expressing cytoplasmic NPM (NPMc(+) AML) carried NPM mutations. None of the 250 cases with nucleus-restricted NPM (NPMc(-) AML) was mutated. At the C-terminus, NPM leukemic mutants carried mutations of only tryptophan 290 or of both tryptophans 288 and 290 and a new nuclear export signal (NES) motif, which appear to underlie their nuclear export. The specific Crm1/exportin-1 inhibitor leptomycin-B relocated NPM mutants from cytoplasm to nucleus of primary NPMc(+) AML cells, demonstrating that nuclear export is NES dependent. NPM mutants bound and recruited wild-type NPM into leukemic cell cytoplasm. Because alterations at C-terminus of leukemic NPM mutants are similar, immunohistochemistry detects all exon-12 NPM mutations and is a valuable, inexpensive tool in the diagnostic-prognostic work-up of patients with AML with normal karyotype.

Active Transport, Cell Nucleus↗
PubMed2006

Marker expression in peripheral T-cell lymphoma: a proposed clinical-pathologic prognostic score.

PURPOSE: Although peripheral T-cell lymphoma, unspecified (PTCL/U), is the most common T-cell tumor in Western countries, no study to date has been based on the application of a wide panel of markers to a large series of patients and assessed the impact of phenotype on survival. We evaluated the expression of 19 markers in 148 PTCLs/U and 45 PTCLs of the angioimmunoblastic type (AILD). PATIENTS AND METHODS: The analysis was performed on tissue microarrays by immunohistochemistry and in situ hybridization. Clinical data were available in 93 PTCL/U patients, most of whom had been included in a previous study proposing a prognostic index (PIT). RESULTS: An aberrant phenotype with frequent loss of CD5 and/or CD7 was typical for PTCLs, irrespective of whether they were U or AILD. Aberrantly expressed proteins rarely included CD20, CD15, and CD30. Positivity for Epstein-Barr virus-associated small RNAs and CD15 expression emerged as adverse prognostic factors. Among PTCLs/U, the proliferation-associated protein Ki-67 turned out to be prognostically relevant and was integrated in a new predictive score, incorporating age (> 60 years), high lactate dehydrogenase, poor performance status, and Ki-67 > or = 80%. This score was associated with the patient outcome (P < .0001) and was found to be more robust than PIT (P = .0043) in the present series. CONCLUSION: Our retrospective analysis shows a wide range of protein expression in PTCLs and proposes a new prognostic index. The latter represents one of the first examples of mixed score (including patient- and tumor-specific factors) applied to malignant lymphomas and may be the basis for future prospective therapeutic trials.

Adult↗
PubMed2006

Aberrant somatic hypermutation in tumor cells of nodular-lymphocyte-predominant and classic Hodgkin lymphoma.

Aberrant somatic hypermutation (SHM) has been identified as a mechanism for genomewide instability in diffuse large B-cell lymphoma (DLBCL). To assess whether aberrant SHM plays a role in the molecular pathogenesis of Hodgkin lymphoma (HL), we investigated microdissected neoplastic cells of nodular lymphocyte-predominant HL (NLPHL; n = 10) and classic HL (cHL; n = 9) for the presence of mutations in the 5' sequences of 4 previously identified aberrant SHM targets (PIM1, PAX5, RhoH/TTF, c-MYC). Mutations in one or more genes were detected in 80% of NLPHLs and 55% of cHLs, with 50% and 30% of patients carrying mutations in 2 or more genes, respectively. The most frequently involved protooncogene was PAX5, mutated in 7 of 9 patients with NLPHL and 2 of 9 patients with cHL. In total, 34 mutations were detected in NLPHL (frequency, 1.04/1,000 bp) and 35 were detected in patients with cHL (frequency, 1.92/1,000 bp). Mutations were of somatic origin because they were absent in control T cells and shared most of the features of the immunoglobulin variable (IGV) gene-associated SHM mechanism-ie, single nucleotide substitutions (n = 63) with rare deletions/insertions (n = 6) and a predominance of transitions over transversions with preferential targeting motifs. Our finding that NLPHL and cHL are targeted by aberrant SHM, as is DLBCL, suggests that these lymphomas may share common molecular pathogenetic events.

Adolescent↗
PubMed2006

Both carboxy-terminus NES motif and mutated tryptophan(s) are crucial for aberrant nuclear export of nucleophosmin leukemic mutants in NPMc+ AML.

We recently identified aberrant cytoplasmic expression of nucleophosmin (NPM) as the immunohistochemical marker of a large subgroup of acute myeloid leukemia (AML) (about one-third of adult AML) that is characterized by normal karyotype and mutations occurring at the exon-12 of the NPM gene. In this paper, we have elucidated the molecular mechanism underlying the abnormal cytoplasmic localization of NPM. All 29 AML-associated mutated NPM alleles so far identified encode abnormal proteins which have acquired at the C-terminus a nuclear export signal (NES) motif and lost both tryptophan residues 288 and 290 (or only the residue 290) which determine nucleolar localization. We show for the first time that both alterations are crucial for NPM mutant export from nucleus to cytoplasm. In fact, the cytoplasmic accumulation of NPM is blocked by leptomycin-B and ratjadones, specific exportin-1/Crm1-inhibitors, and by reinsertion of tryptophan residues 288 and 290, which respectively relocate NPM mutants in the nucleoplasm and nucleoli. NPM leukemic mutants in turn recruit the wild-type NPM from nucleoli to nucleoplasm and cytoplasm. These findings indicate that potential therapeutic strategies aimed to retarget NPM to its physiological sites will have to overcome 2 obstacles, the new NES motif and the mutated tryptophan(s) at the NPM mutant C-terminus.

Active Transport, Cell Nucleus↗
PubMed2006

Nucleophosmin and cancer.

NPM1 is a crucial gene to consider in the context of the genetics and biology of cancer. NPM1 is frequently overexpressed, mutated, rearranged and deleted in human cancer. Traditionally regarded as a tumour marker and a putative proto-oncogene, it has now also been attributed with tumour-suppressor functions. Therefore, NPM can contribute to oncogenesis through many mechanisms. The aim of this review is to analyse the role of NPM in cancer, and examine how deregulated NPM activity (either gain or loss of function) can contribute to tumorigenesis.

Animals↗
PubMed2006

Evolving concepts in the pathogenesis of hairy-cell leukaemia.

Hairy-cell leukaemia (HCL) has long been recognized as distinct from other chronic B-cell malignancies, but several questions remain unanswered. What is the HCL cell of origin? Why does HCL lack the hallmarks of most mature B-cell tumours (for example, chromosomal translocations and consistent lymph node involvement) and show unique features like 'hairy' morphology and bone-marrow fibrosis? Gene-expression profiling and other studies have recently provided new insights into HCL biology and have the potential to affect clinical practice.

Animals↗
PubMed2006

Denaturing high-performance liquid chromatography: a valid approach for identifying NPM1 mutations in acute myeloid leukemia.

NPM1 gene mutations are the most frequent genetic lesion in the 60% of adult acute myeloid leukemias (AMLs) with normal karyotype and no evidence of typical fusion genes (BCR/ABL1, PML/RARA, AML1/ETO, CBFB/MYH11, DEK/CAN). Using direct sequencing we previously identified six different heterozygous mutants within exon 12 encoding the nucleophosmin C-terminus. Because of these mutations the shuttling protein nucleophosmin is aberrantly delocalized in the cytoplasm of leukemic cells (NPMc+). Here, we designed and tested a denaturing high-performance liquid chromatography (DHPLC) assay to detect NPM1 mutated variants. To assess specificity, sensitivity, reliability, and reproducibility, we analyzed DNA from 120 primary adult AMLs and compared DHPLC results with immunohistochemistry and sequencing. All electropherogram profiles in the 26 NPMc+ leukemias were different from the wild type, indicating 100% sensitivity. Sequencing categorized mutations A, B, and D, and all mutation A cases gave identical elution profiles. The other mutations showed typical chromatograms, with mutations B and D differing for one nucleotide. Elution profiles and sequencing also identified four new variants. Our results suggest that DHPLC detects NPM1mutations as well as direct sequencing and immunohistochemistry, providing a helpful approach in the diagnosis of NPMc+ AML.

Amino Acid Sequence↗
PubMed2005

Nucleophosmin gene mutations are predictors of favorable prognosis in acute myelogenous leukemia with a normal karyotype.

Nucleophosmin (NPM1) exon-12 gene mutations are the hallmark of a large acute myelogenous leukemia (AML) subgroup with normal karyotype, but their prognostic value in this AML subset has not yet been determined. We screened 401 AML patients with normal karyotype treated within the German AML Cooperative Group Protocol 99 (AMLCG99) study for NPM1 mutations. Results were related with partial tandem duplications within the MLL gene (MLL-PTD), Fms-like tyrosine kinase 3-length mutations (FLT3-LM), the tyrosine kinase domain of FLT3 (FLT3-TKD), NRAS, KIT, and CEBPA mutations and with clinical characteristics and outcome. NPM1 mutations were detected in 212 (52.9%) of 401 patients. Fourteen mutations, including 8 new variants, were identified. NPM1-mutated cases associated frequently with FLT3 mutations but rarely with other mutations. The NPM1-mutated group had a higher complete remission (CR) rate (70.5% vs 54.7%, P = .003), a trend to a longer overall survival (OS; median 1012 vs 549 days, P = .076), and significantly longer event-free survival (EFS; median 428 vs 336 days; P = .012). The favorable impact of NPM1 mutations on OS and EFS clearly emerged in the large group (264 [66.8%] of 395 cases) of normal-karyotype AML without FLT3-LM. This positive effect was lost in the presence of a concomitant FLT3-LM, since survival of the NPM1+/FLT3-LM+ double positive was similar to NPM1-/FLT3-LM+ cases. In conclusion, this study demonstrates that NPM1+/FLT3-LM- mutations are an independent predictor for a favorable outcome in AML with normal karyotype.

Adolescent↗
PubMed2005

Computational modeling of the immune response to tumor antigens.

Vaccination protocols designed to elicit anti-cancer immune responses have, many times, failed in producing tumor eradication and in prolonging patient survival. Usually in cancer vaccination, epitopes from one organism are included in the genome or linked with some protein of another in the hope that the immunogenic properties of the latter will boost an immune response to the former. However, recent results have demonstrated that injections of two different vectors encoding the same recombinant antigen generate high levels of specific immunity. Systematic comparison of the efficacy of different vaccination protocols has been hampered by technical limitations, and clear evidence that the use of multiple vectors has advantages over single carrier injections is lacking. We used a computational model to investigate the dynamics of the immune response to different anti-cancer vaccines based on randomly generated antigen/carrier compounds. The computer model was adapted for simulations to this new area in immunology research and carefully validated to the purpose. As a matter of fact, it reproduces a relevant number of experimental observations. The model shows that when priming and boosting with the same construct, competition rather than cooperation develops amongst T cell clones of different specificities. Moreover, from the simulations, it appears that the sequential use of multiple carriers may generate more robust anti-tumor immune responses and may lead to effective tumor eradication in a higher percentage of cases. Our results provide a rational background for the design of novel strategies for the achievement of immune control of cancer.

Animals↗
PubMed2005

Nucleophosmin mutations in childhood acute myelogenous leukemia with normal karyotype.

Nucleophosmin (NPM) is a nucleocytoplasmic shuttling protein involved in leukemia-associated chromosomal translocations, and it regulates the alternate reading frame (ARF)-p53 tumor-suppressor pathway. Recently, it has been demonstrated that mutations of the NPM1 gene alter the protein at its C-terminal, causing its cytoplasmic localization. Cytoplasmic NPM was detected in 35% of adult patients with primary non-French-American-British (FAB) classification M3 acute myeloid leukemia (AML), associated mainly with normal karyotype. We evaluated the prevalence of the NPM1 gene mutation in non-M3 childhood AML patients enrolled in the ongoing Associazione Italiana di Ematologia e Oncologia Pediatrica (AIEOP-AML02) protocol in Italy. NPM1 mutations were found in 7 (6.5%) of 107 successfully analyzed patients. NPM1-mutated patients carried a normal karyotype (7/26, 27.1%) and were older in age. Thus, the NPM1 mutation is a frequent abnormality in AML patients without known genetic marker; the mutation may represent a new target to monitor minimal residual disease in AML and a potential candidate for alternative and targeted treatments.

Adolescent↗
PubMed2005

Acute myeloid leukemia bearing cytoplasmic nucleophosmin (NPMc+ AML) shows a distinct gene expression profile characterized by up-regulation of genes involved in stem-cell maintenance.

Approximately one third of acute myeloid leukemias (AMLs) are characterized by aberrant cytoplasmic localization of nucleophosmin (NPMc+ AML), consequent to mutations in the NPM putative nucleolar localization signal. These events are mutually exclusive with the major AML-associated chromosomal rearrangements, and are frequently associated with normal karyotype, FLT3 mutations, and multilineage involvement. We report the gene expression profiles of 78 de novo AMLs (72 with normal karyotype; 6 without major chromosomal abnormalities) that were characterized for the subcellular localization and mutation status of NPM. Unsupervised clustering clearly separated NPMc+ from NPMc- AMLs, regardless of the presence of FLT3 mutations or non-major chromosomal rearrangements, supporting the concept that NPMc+ AML represents a distinct entity. The molecular signature of NPMc+ AML includes up-regulation of several genes putatively involved in the maintenance of a stem-cell phenotype, suggesting that NPMc+ AML may derive from a multipotent hematopoietic progenitor.

Acute Disease↗
PubMed2005

Cytoplasmic nucleophosmin in acute myelogenous leukemia with a normal karyotype.

BACKGROUND: Nucleophosmin (NPM), a nucleocytoplasmic shuttling protein with prominent nucleolar localization, regulates the ARF-p53 tumor-suppressor pathway. Translocations involving the NPM gene cause cytoplasmic dislocation of the NPM protein. METHODS: We used immunohistochemical methods to study the subcellular localization of NPM in bone marrow-biopsy specimens from 591 patients with primary acute myelogenous leukemia (AML). We then correlated the presence of cytoplasmic NPM with clinical and biologic features of the disease. RESULTS: Cytoplasmic NPM was detected in 208 (35.2 percent) of the 591 specimens from patients with primary AML but not in 135 secondary AML specimens or in 980 hematopoietic or extrahematopoietic neoplasms other than AML. It was associated with a wide spectrum of morphologic subtypes of the disease, a normal karyotype, and responsiveness to induction chemotherapy, but not with recurrent genetic abnormalities. There was a high frequency of FLT3 internal tandem duplications and absence of CD34 and CD133 in AML specimens with a normal karyotype and cytoplasmic dislocation of NPM, but not in those in which the protein was restricted to the nucleus. AML specimens with cytoplasmic NPM carried mutations of the NPM gene that were predicted to alter the protein at its C-terminal; this mutant gene caused cytoplasmic localization of NPM in transfected cells. CONCLUSIONS: Cytoplasmic NPM is a characteristic feature of a large subgroup of patients with AML who have a normal karyotype, NPM gene mutations, and responsiveness to induction chemotherapy.

Adolescent↗
PubMed2005

Interleukin 7-engineered stromal cells: a new approach for hastening naive T cell recruitment.

In this study we determined whether human stromal cells could be engineered with a retroviral vector carrying the interleukin 7 (IL-7) gene and investigated the effects on T cells in vitro and in vivo in a murine model. Transduced mesenchymal cells strongly express CD90 (98.15%), CD105 (87.6%), and STRO-1 (86.7%). IL-7 production was 16.37 (+/-2 SD) pg/ml, which remained stable for 60 days. In vitro-immunoselected naive T cells maintained the CD45RA+ CD45RO- naive phenotype (4.2 times more than controls) after 7 days of culture with IL-7-engineered stromal cells. The apoptosis rate (4.7%) of the naive T cells cultured with transduced stromal cells overlapped with that of freshly isolated cells. Immunohistological analysis detected stromal cells in bone marrow, spleen, and thymus. Cotransplantation of IL-7-engineered stromal cells with CD34+ cells improved engraftment in terms of CD45+ cells and significantly increased the CD3+ cell count in peripheral blood, bone marrow, and spleen. These data demonstrate the following: (1) human stromal cells can be transduced, generating a normal layer; (2) transduced stromal cells in vitro maintain the naive T cell phenotype; and (3) IL-7-transduced stromal cells in vivo home to lymphoid organs and produce sufficient IL-7 in loco, supporting T cell development in a cotransplantation model. Because of their efficient cytokine production and homing, IL-7-engineered stromal cells might be an ideal vehicle to hasten immunological reconstitution in T cell-depleted hosts.

Animals↗
PubMed2005

Epstein-barr virus infection of monocytoid B-cell proliferates: an early feature of primary viral infection?

Monocytoid cells are a subset of B lymphocytes with characteristic morphology and immunophenotype, which proliferate in a broad variety of reactive lymph node conditions. Up to now, no direct infection of these cells by a pathogenic organism has been identified. We found in a series of lymph node specimens from 13 patients having in common a prominent monocytoid B (MCB)-cell reaction in the absence of epithelioid cells or necrosis evidence that Epstein-Barr virus (EBV) can infect MCB cells. Clinical and serologic findings indicative for an acute EBV infection were reported only in 2 cases. By in situ hybridization and immunohistology, a number of MCB cells in all cases was found to contain EBV-encoded small nuclear RNAs and to express the EBV-encoded nuclear antigen (EBNA)-2 and, in lesser extent, the latent membrane protein-1. EBV-transcripts and proteins were also detectable in a number of extrafollicular B blasts and germinal center B cells in 10 of 13 cases. Our findings imply that an EBV infection of MCB cells associated with predominant EBNA-2 expression represents an early sign of primary infection and that it should be included in the differential diagnosis of activated lymph nodes with prominent MCB-cell reaction in the absence of epithelioid cells.

Adolescent↗