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Aggressive B‐cell lymphomas present as a heterogeneous spectrum of disease. A primary diagnosis in the bone marrow (BM) may be challenging in terms of diagnostic classification and clinical handling, owing to limited architectural information. Aggressive B‐cell lymphomas can be subdivided into entities that typically present primarily in the BM, and cases with BM involvement in which the bulk of disease is present in other organs. One main topic at the 2018 BM workshop of the European Association of Haematopathology/Society of Hematopathology was therefore aggressive B‐cell lymphomas with a primary BM presentation. The spectrum of cases submitted to this topic gave a good overview of commonly encountered problems, as well as unusual manifestations, and highlighted areas of imprecise disease definitions and diagnostic grey zones. The categories submitted to the workshop included cases of Burkitt lymphoma (BL) with unusual features, high‐grade B‐cell lymphomas (HG‐BCLs) with and without so‐called double/triple‐hit, and diffuse large B‐cell lymphomas (DLBCLs) with a primary BM presentation. Areas of difficulties included the morphological boundaries of HG‐BCL not otherwise specified, cases with MYC and bcl‐2 or bcl‐6 translocations and terminal deoxynucleotidyl transferase (TdT) expression, which were categorised as B‐cell lymphoblastic leukaemia/lymphoma if most cells showed TdT positivity, and the clinicopathological overlap between intravascular large B‐cell lymphoma, CD5‐positive DLBCL, and DLBCL with primary presentations in the BM, spleen, and liver. This review summarises our understanding of the main aggressive B‐cell lymphoma categories with a common primary BM presentation and potential problem areas, and makes suggestions for the immunophenotypic and genetic work‐up, illustrated by the interesting and challenging cases submitted to the workshop. [ABSTRACT FROM AUTHOR]

I Sir: i The 3rd session of the bone marrow (BM) workshop of the 19th meeting of the European Association for Haematopathology (EAHP)/Society of Hematopathology (SH) in Edinburgh in 2018 was dedicated to T-cell and natural killer (NK)/T-cell lymphomas/lymphoproliferations. In this article we discuss cases submitted to the 3rd session of the EAHP/SH BM workshop and focus on diagnostic challenges, including the difficulties in clarifying borders between overlapping primary BM T-cell and NK/T-cell lymphoproliferations, and the limitations of applying existing diagnostic criteria related to nodal-type T-cell lymphomas or extranodal NK/T-cell (ENKT) lymphoproliferations to rare cases of isolated involvement or initial presentation in the BM. GLO:EW1/01jul20:his14093-fig-0003.jpg PHOTO (COLOR): 3 Angioimmunoblastic T-cell lymphoma with bone marrow (BM) involvement that was obscured by a dense polytypic plasmacytic infiltrate, and a case of primary BM involvement by peripheral T-cell lymphoma expressing T follicular helper cell (TFH) markers. A,B, Bone marrow (BM) examination of case no. 21/217 showed dense infiltration by two topographically and morphologically distinct lymphoid infiltrates: confluent nodules of small lymphoid cells [A, haematoxylin and eosin (H&E)], and (B) many large bizarre atypical lymphoid cells in a fibrotic background of small lymphoid cells and histiocytes (B, H&E). [Extracted from the article]

Summary: Predominantly diffuse t(14;18) negative follicular lymphoma (FL) with 1p36 deletion shows distinctive clinical, morphological and molecular features that distinguish it from classical FL. In order to investigate whether it possesses a unique mutation profile, we performed whole exome sequencing of six well‐characterised cases. Our analysis showed that the mutational landscape of this subtype is largely distinct from classical FL. It appears to harbour several recurrent mutations, affecting STAT6, CREBBP and basal membrane protein genes with high frequency. Our data support the view that this FL subtype should be considered a separate entity from classical FL. [ABSTRACT FROM AUTHOR]

Background: small B-cell neoplasms can show plasmacytic differentiation and may potentially progress to aggressive lymphoma (DLBCL). Epstein-Barr virus (EBV) infection may cause the transformation of malignant cells in vitro. Design and Method: we established VR09 cell line with plasmacytic differentiation, obtained from a case of atypical, non- CLL B-cell chronic lymphoproliferative disease with plasmacytic features. We used flow cytometry, immunohistochemistry, polymerase chain reaction, cytogenetic analysis and florescence in situ hybridization in the attempt at thoroughly characterizing the cell line. We showed VR09 tumorigenic potential in vivo, leading to the development of activated DLBCL with plasmacytic features. Results: VR09 cells displayed plasmacytic appearance and grew as spherical tumors when inoculated subcutaneously into immunodeficient Rag2-/- γ-chain-/- mice. VR09 cell line and tumors displayed the phenotype of activated stage of B cell maturation, with secretory differentiation (CD19+ CD20+ CD79a+ CD79b+/2 CD138+ cyclin D1- Ki67 80% IgM+ IgD+ MUM1+ MNDA+ CD10- CD22+ CD23+ CD43+ K+, γ- Bcl2+ Bcl6-) and they presented episomal EBV genome, chromosome 12 trisomy, lack of c-MYC rearrangement and Myd88 gene mutation, presence of somatic hypermutation in the VH region, and wild-type p53. Conclusion: This new EBV-positive cell line may be useful to further characterize in vivo activated DLBCL with plasmacytic features. [ABSTRACT FROM AUTHOR]

Abstract: Proteomic analysis of cancer tissues and cells provides valuable information to identify promising targets for cancer diagnosis, prognosis and therapy. Novel strategies have emerged to optimize the workflow of tissue procurement, and tissue and cell selection, and to improve protocols for the extraction of protein from fresh, frozen and paraffin-embedded tissue. Moreover, in the context of advanced approaches to proteomics, mass spectrometry and array-based technologies strongly contribute to protein profiling of cancer tissues and cells. The focus of this review is the methods by which all the steps of a proteomic investigation on human-cancer tissue (from choice of the experimental model to validation of candidate biomarkers) should be performed, paying particular attention to recently developed strategies. The review also presents an overview of the most recent high-throughput proteomic studies in cancer research. [Copyright &y& Elsevier]

Abstract: Lymphoid and haematopoietic neoplasms comprise a broad spectrum of different tumours, classified by the World Health Organization (WHO) on the basis of a combination of morphology, immunophenotypic, genetic and clinical features. Up to date for many of these neoplasms no single feature is regarded as a diagnostic gold standard. The application of proteomics to the study of neoplastic haematological diseases could help in the search for new diagnostic and prognostic markers, as well as in the development of new therapeutic strategies. In this review, we focus on the actual role of proteomics technologies in the study of neoplastic haematology. In particular, we analyse the results obtained in the field of body fluid, cell lines, and tissues proteomics, and discuss the improvement allowed by the new developed proteomic strategies, such as nanofluidic systems, analysis of formalin-fixed tissues, and quantitative high throughput techniques (SILAC, ICAT, iTRAQ). [Copyright &y& Elsevier]

Background: Fibroblast foci (FF) are considered a relevant morphologic marker of idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP), and are recognised as sites where fibrotic responses are initiated and/or perpetuated in this severe disease. Despite their relevance, the cellular and molecular mechanisms responsible for the formation of FF and their role in tissue remodelling are poorly defined. In previous studies we have provided evidence of abnormal activation of the wnt-signaling-pathway in IPF/UIP that is centred on FF and the overlying epithelium. This important morphogenetic pathway is able to trigger epithelial-mesenchymal-transition (EMT), a mechanism involved in developmental and metastatic processes, which is also potentially involved in pulmonary fibrosis. Methods: Since EMT is characterised by enhancement of migratory potential of cells, we investigated the molecular profile of FF in 30 biopsies of IPF/UIP and a variety of control samples, focussing on the immunohistochemical expression of three molecules involved in cell motility and invasiveness, namely laminin-5-γ2-chain, fascin, and heat-shock-protein-27. Results: We provide evidence that in UIP these three molecules are abnormally expressed in discrete clusters of bronchiolar basal cells precisely localised in FF. These cellular clusters expressed laminin-5-γ2-chain and heat-shockprotein- 27 at very high levels, forming characteristic three-layered lesions defined as "sandwich-foci" (SW-FF). Upon quantitative analysis SW-FF were present in 28/30 UIP samples, representing more than 50% of recognisable FF in 21/30, but were exceedingly rare in a wide variety of lung pathologies examined as controls. In UIP, SW-FF were often observed in areas of microscopic honeycombing, and were also found at the interface between normal lung tissue and areas of dense scarring. Conclusion: These molecular abnormalities strongly suggest that SW-FF represent the leading edge of pulmonary remodelling, where abnormal migration and re-epithelialisation take place, and that abnormal proliferation and migration of bronchiolar basal cells have a major role in the remodelling process characterising IPF/UIP. Further investigations will assess their possible use as reliable markers for better defining the UIP-pattern in difficult cases. [ABSTRACT FROM AUTHOR]

In classical Hodgkin lymphoma (cHL), the significance of the interplay between Hodgkin and Reed–Sternberg cells (HRS) and reactive T cells remains poorly defined. By immunohistochemistry on bioptic cHL specimens, we found that HRS and surrounding T lymphocytes stained positive for IL-17 in 40% of cases. IL-17 was detectable in a similar proportion of patients' sera and correlated with disease burden. Supernatants of KM-H2 and HDLM-2 cHL cell lines guided preferential chemotaxis of CCR6+ T lymphocytes. Coculture of cHL cell lines with PBMC promoted the enrichment of Th17 lymphocytes and Foxp3+/IL-17+ cells, whereas T regulatory cells slightly decreased. Soluble CD30 downmodulated membrane CD30 expression on T cells and contributed to their polarization shift by stimulating IL-17 production and reducing IFN-γ synthesis. Thus, HRS and a number of reactive CD4+ T cells, attracted by tumor-secreted chemokines, produce an IL-17 tumor-shaped inflammatory milieu in a cHL subset. [ABSTRACT FROM AUTHOR]

Background: Several viruses have been described as causes of acquired inflammatory myopathies; however, the mechanisms by which they cause muscle disease are still unclear. The aim of this study was to describe the laboratory features of benign acute myositis in a small case series.Methods: A detailed pathological and serological analysis was performed in five African migrants who developed an acute viral myositis complicated by rhabdomyolysis.Results: Muscle biopsies clearly documented an inflammatory myopathy with histological features similar to polymyositis including CD8+ T cells surrounding and invading nonnecrotic muscle fibers, CD68+ macrophages and major histocompatibility complex class I antigen upregulation. In addition, positivity for myositis-specific antibodies (MSA), in particular anti-aminoacyl tRNA synthetases, was found in the serum of two patients.Conclusions: Our study demonstrated that T-cell mediated injury occurs in muscle of patients with acute viral myositis, and that MSA may be present in the serum of these patients. [ABSTRACT FROM AUTHOR]

Summary: High programmed cell death 1 ligand 1 (PD‐L1) protein expression and copy number alterations (CNAs) of the corresponding genomic locus 9p24.1 in Hodgkin‐ and Reed–Sternberg cells (HRSC) have been shown to be associated with favourable response to anti‐PD‐1 checkpoint inhibition in relapsed/refractory (r/r) classical Hodgkin lymphoma (cHL). In the present study, we investigated baseline 9p24.1 status as well as PD‐L1 and major histocompatibility complex (MHC) class I and II protein expression in 82 biopsies from patients with early stage unfavourable cHL treated with anti‐PD‐1‐based first‐line treatment in the German Hodgkin Study Group (GHSG) NIVAHL trial (ClinicalTrials.gov Identifier: NCT03004833). All evaluated specimens showed 9p24.1 CNA in HRSC to some extent, but with high intratumoral heterogeneity and an overall smaller range of alterations than reported in advanced‐stage or r/r cHL. All but two cases (97%) showed PD‐L1 expression by the tumour cells in variable amounts. While MHC‐I was rarely expressed in >50% of HRSC, MHC‐II expression in >50% of HRSC was found more frequently. No obvious impact of 9p24.1 CNA or PD‐L1 and MHC‐I/II expression on early response to the highly effective anti‐PD‐1‐based NIVAHL first‐line treatment was observed. Further studies evaluating an expanded panel of potential biomarkers are needed to optimally stratify anti‐PD‐1 first‐line cHL treatment. [ABSTRACT FROM AUTHOR]

Background: Increased numbers of tumour-associated macrophages correlate with shortened survival in some cancers. The molecular bases of this correlation are not thoroughly understood. Events triggered by CXCL12 may play a part, as CXCL12 drives the migration of both CXCR4-positive cancer cells and macrophages and may promote a molecular crosstalk between them. Results: Samples of HER1-positive colon cancer metastases in liver, a tissue with high expression of CXCL12, were analysed by immunohistochemistry. In all of the patient biopsies, CD68-positive tumour-associated macrophages presented a mixed CXCL10 (M1)/CD163 (M2) pattern, expressed CXCR4, GM-CSF and HB-EGF, and some stained positive for CXCL12. Cancer cells stained positive for CXCR4, CXCL12, HER1, HER4 and GM-CSF. Regulatory interactions among these proteins were validated via experiments in vitro involving crosstalk between human mononuclear phagocytes and the cell lines DLD-1 (human colon adenocarcinoma) and HeLa (human cervical carcinoma), which express the above-mentioned ligand/receptor repertoire. CXCL12 induced mononuclear phagocytes to release HB-EGF, which activated HER1 and triggered anti-apoptotic and proliferative signals in cancer cells. The cancer cells then proliferated and released GM-CSF, which in turn activated mononuclear phagocytes and induced them to release more HB-EGF. Blockade of GM-CSF with neutralising antibodies or siRNA suppressed this loop. Conclusions: CXCL12-driven stimulation of cancer cells and macrophages may elicit and reinforce a GM-CSF/HBEGF paracrine loop, whereby macrophages contribute to cancer survival and expansion. The involvement of mixed M1/M2 GM-CSF-stimulated macrophages in a tumour-promoting loop may challenge the paradigm of tumourfavouring macrophages as polarized M2 mononuclear phagocytes. [ABSTRACT FROM AUTHOR]

Primary pancreatic lymphoma (PPL) is a rare disease representing 0.1% of malignant lymphomas, which lacks well‐defined diagnostic and therapeutic protocols. Objectives: To describe PPL clinical, diagnostic and histological characteristics, together with therapy and outcome, in a relatively large series of patients. Methods: The study includes 39 PPL patients, aged ≥15 years, observed from January 2005 to December 2018, in 8 Italian Institutions. Results: The main symptoms were abdominal pain (58%) and jaundice (47%). Lactate dehydrogenase serum levels were elevated in 43% of patients. Histological specimens were mostly obtained by percutaneous (41%) or endoscopic (36%) biopsy, with diffuse large B‐cell lymphoma being the most frequent (69%) histological diagnosis. Chemotherapy was administered alone in 65% of patients, with radiotherapy in 17%, or after surgery in 9%. The 2‐year overall survival (OS) was 62%, the 2‐year progression‐free survival (PFS) 44%. Debulking surgery (with or without chemotherapy) was associated with a significant worse OS. Three (9.4%) of 32 high‐grade patients experienced a central nervous system (CNS) relapse. Conclusions: PPL is rare, often high‐grade, with symptoms and localization similar to other pancreatic malignancies. Biopsy should be the preferred diagnostic method. High‐grade PPL should undergo CNS prophylaxis. [ABSTRACT FROM AUTHOR]

PURPOSE: Data collection in clinical trials is becoming complex, with a huge number of variables that need to be recorded, verified, and analyzed to effectively measure clinical outcomes. In this study, we used data warehouse (DW) concepts to achieve this goal. A DW was developed to accommodate data from a large clinical trial, including all the characteristics collected. We present the results related to baseline variables with the following objectives: developing a data quality (DQ) control strategy and improving outcome analysis according to the clinical trial primary end points. METHODS: Data were retrieved from the electronic case reporting forms (eCRFs) of the phase III, multicenter MCL0208 trial (ClinicalTrials.gov identifier: NCT02354313) of the Fondazione Italiana Linfomi for younger patients with untreated mantle cell lymphoma (MCL). The DW was created with a relational database management system. Recommended DQ dimensions were observed to monitor the activity of each site to handle DQ management during patient follow-up. The DQ management was applied to clinically relevant parameters that predicted progression-free survival to assess its impact. RESULTS: The DW encompassed 16 tables, which included 226 variables for 300 patients and 199,500 items of data. The tool allowed cross-comparison analysis and detected some incongruities in eCRFs, prompting queries to clinical centers. This had an impact on clinical end points, as the DQ control strategy was able to improve the prognostic stratification according to single parameters, such as tumor infiltration by flow cytometry, and even using established prognosticators, such as the MCL International Prognostic Index. CONCLUSION: The DW is a powerful tool to organize results from large phase III clinical trials and to effectively improve DQ through the application of effective engineered tools. [ABSTRACT FROM AUTHOR]

Calreticulin (CALR) mutations are detected in the majority of JAK2 wild type patients with essential thrombocythemia (ET). Unlike JAK2V617F and MPL point mutations, CALR mutations are highly heterogeneous, with several types of indels being reported so far. CAL2 is a monoclonal antibody specifically recognizing the C-neoterminal peptide derived from all the frameshift mutations of CALR. We retrospectively analysed 172 ET patients diagnosed at our Institution from 1980 to 2015. In JAK2V617F- and MPLW515K/L-wild type patients CALR mutations were searched on peripheral blood and CAL2 immunostaining was performed on bone marrow. In addition, bone marrow biopsies were histologically reviewed for megakaryocytic features. Thirty-one patients (18%) were CALR-mutated. Concordance between molecular and immunohistological detection of CALR mutations was near complete, albeit a single patient was found to be positive by molecular tests only. Two patterns were defined in CAL2-positive bone marrow samples, characterized by staining of almost only megakaryocytes (pattern A: 41%) or staining of megakaryocytes and ≥ 2% small non megakaryocytic elements (pattern B: 59%), at least partially being myeloid precursors. Pattern B biopsies had higher cellularity and number of megakaryocytes compared to pattern A samples. In this series, CAL2 allowed rapid and cost-efficient identification of CALR-mutated ET patients. The biological significance of different staining pattern should be confirmed in wider and independent series. [ABSTRACT FROM AUTHOR]

The authors offer a response to criticisms raised about their study on the role of the endothelin-1 (EDN1) axis as a therapeutic target in multiple myeloma (MM). Topics include recognition of aberrant activation of the EDN1 axis as a common mechanism underlying the progression of several solid and blood malignancies, molecular basis of the aberrant expression of EDN receptor B (EDNRB), and effects of EDNRs blockade.

Key Clinical Message Patients with advanced variants of Systemic Mastocytosis may develop destructive bone lesions when massive mast cell ( MC) infiltrates are present. Finding of large osteolyses in indolent systemic mastocytosis, typically characterized by low MC burden, should prompt investigations for an alternative explanation. [ABSTRACT FROM AUTHOR]

New effective treatments are needed to improve outcomes for multiple myeloma ( MM) patients. Receptors with restricted expression on plasma cells ( PCs) represent attractive new therapeutic targets. The endothelin-1 ( EDN1) axis, consisting of EDN1 acting through EDN-receptor A ( EDNRA) and B ( EDNRB), was previously shown to be overexpressed in several tumours, including MM. However, there is incomplete understanding of how EDN1 axis regulates MM growth and response to therapy. Besides EDNRA, the majority of MM cell lines and primary malignant PCs express high levels of EDNRB and release EDN1. Similarly, bone-marrow microenvironment cells also secrete EDN1. Investigating the extent of epigenetic dysregulation of EDNRB gene in MM, we found that hypermethylation of EDNRB promoter and subsequent down-regulation of EDNRB gene was observed in PCs or B lymphocytes from healthy donors compared to EDNRB-expressing malignant PCs. Pharmacological blockade with the dual EDN1 receptor antagonist bosentan decreased cell viability and MAPK activation of U266 and RPMI-8226 cells. Interestingly, the combination of bosentan and the proteasome inhibitor bortezomib, currently approved for MM treatment, resulted in synergistic cytotoxic effects. Overall, our data has uncovered EDN1-mediated autocrine and paracrine mechanisms that regulate malignant PCs growth and drug response, and support EDN1 receptors as new therapeutic targets in MM. [ABSTRACT FROM AUTHOR]

The prognosis of patients affected by myelofibrosis (MF) is usually dismal and allogeneic hematopoietic stem cell transplantation (HSCT) remains the only cure. The number of HSCTs in MF patients has recently increased. However, a major obstacle is still represented by primary graft failure (PGF). Currently there are no definitive guidelines for the treatment of PGF and a second HSCT can be performed only when an allogeneic donor is rapidly available. Herein we report on a MF patient with PGF after an unrelated HSCT, who was rescued by a non-myeloablative, unmanipulated, haploidentical HSCT that resulted in persistent engraftment and bone-marrow fibrosis regression, but not in a long-term disease control. Based on this experience we briefly review the role of different conditioning regimens and hematopoietic stem cell sources in the setting of HSCT for MF patients with PGF. The role of haploidentical donors in MF patients lacking HLAmatched relatives is also discussed. [ABSTRACT FROM AUTHOR]

Splenic marginal zone lymphoma Is a rare lymphoma. Loss of 7q31 and somatic mutations affecting the NOTCH2 and KLF2 genes are the commonest genomic aberrations. Epigenetic changes can be pharmacologically reverted: therefore, identification of groups of patients with specific epigenomic alterations might have therapeutic relevance. Here we integrated genome-wide DNA-promoter methylation profiling with gene expression profiling, and clinical and biological variables. An unsupervised clustering analysis of a test series of 98 samples Identified 2 clusters with different degrees of promoter methylation. The cluster comprising samples with higher-promoter methylation (High-M) had a poorer overall survival compared with the lower (Low-M) cluster. The prognostic relevance of the High M phenotype was confirmed in an Independent validation set of 36 patients. In the whole series, the High-M phenotype was associated with IGHV1-02 usage, mutations of N0TCH2 gene, 7q31-32 loss, and histologic transformation. In the High-M set, a number of tumor-suppressor genes were methylated and repressed. PRC2 subunit genes and several prosurvlval lymphoma genes were unmethylated and overexpressed. A model based on the methylation of 3 genes (CACNB2, HTRA1, KLF-1) identified a poorer-outcome patient subset. Exposure of splenic marginal zone lymphoma cell lines to ademethylating agent caused partial reversion of the High-M phenotype and Inhibition of proliferation. [ABSTRACT FROM AUTHOR]

Patients with Systemic Mastocytosis (SM) need a highly sensitive diagnostic test for D816V detection of the KIT receptor gene. Along with histology/cytology and flow cytometry evaluation, bone marrow (BM) from 110 consecutive adult patients referred with a suspicion of SM to Multidisciplinary Outpatient Clinic for Mastocytosis in Verona were tested both by Amplification Refractory Mutation System Reverse Transcriptase quantitative real time Polymerase Chain Reaction (ARMS-RT-qPCR) and RT-PCR + Restriction Fragment Length Polymorphism (RFLP) followed by Denaturing-High Performance Liquid Chromatography (D-HPLC) and Sanger sequencing. ARMS-RT-qPCR identified D816V mutation in 77 patients, corresponding to 100% of cases showing CD25 + mast cells (MCs) whereas RT-PCR + RFLP/D-HPLC + sequencing revealed D816V mutations in 47 patients. According to the 2008 WHO criteria 75 SM, 1 Cutaneous Mastocytosis (CM), 1 monoclonal MC activation syndrome (MMAS), and 1 SM Associated with Haematologic Non-Mast Cell Disorder (SM-AHNMD) were diagnosed. Seventeen out 75 SM patients (23%) would have not satisfied sufficient WHO criteria on the basis of the sole RT-PCR + RFLP: these patients had significantly lower serum tryptase levels and amount of CD25 + MCs. Therefore, ARMS-RT-qPCR might result particularly useful, in patients that do not fulfil major BM histological criterion, for the recognition of indolent SM with a very low MC burden. [ABSTRACT FROM AUTHOR]

The clonal/neoplastic nature of Langerhans cell histiocytosis (LCH) has recently been demonstrated by a high prevalence of BRAF mutations, including pulmonary LCH (PLCH). We hypothesized that BRAF-induced senescence, as demonstrated in nevi and melanoma, is involved in the pathogenesis of LCH and PLCH. In a series of pulmonary (19 cases) and non-pulmonary LCH (19 cases), including five aggressive cases, we investigated occurrence of the BRAF V600E mutation by molecular analysis and/or immunohistochemistry using a validated antibody (VE1). The expression of cell-senescence markers p16INK4a and p21CIP1/WAF1 was also immunohistochemically investigated. We demonstrated that 6/19 cases of LCH and 12/19 cases of PLCH were VE1 positive, matching with molecular analysis, and in all cases both p16INK4a and p21CIP1/WAF1 were expressed, irrespective of BRAF mutation status. Interestingly, all the aggressive cases did not express p16INK4a, thus suggesting that loss of senescence control could be related to clinical aggressiveness of LCH, as in melanoma. [ABSTRACT FROM AUTHOR]

Aims CD30 expression by bone marrow ( BM) mast cells ( MC) has been reported recently in systemic mastocytosis ( SM) patients. The aim of this study was to investigate the potential diagnostic and prognostic value of CD30 expression in SM as assessed by multiparameter flow cytometry. Methods and results A total of 163 consecutive BM samples corresponding to 142 SM patients and 21 non-mastocytosis cases were studied. CD30 was positive in most SM patients (80%), but in only one non-mastocytosis case (4.8%). When combined with CD25, CD30 contributed to an improved accuracy over that of CD25 alone (98% versus 93%) mainly because most (eight of nine) of the well-differentiated SM ( WDSM), who lacked CD25, were CD30+. Similar levels of expression of CD30 were observed among all different subgroups of SM except mast cell leukaemia; among indolent SM ( ISM) patients, no significant association was observed between the levels of CD30 expression and other clinical and biological features of the disease. Conclusions The increased expression of CD30 associated with absence of CD25 contributes to the diagnosis of WDSM and its distinction from other subtypes of SM. By contrast, CD30 expression did not contribute either to prognostic stratification of ISM or to the differential diagnosis between ISM and aggressive SM cases. [ABSTRACT FROM AUTHOR]

Mantle cell lymphoma shows a peculiar immunogenetic profile, but the functional consequences of this fact are unknown. We have determined the precise sequences of rearranged heavy and light chain genes in several mantle cell lymphoma cell lines and investigated the presence of heavy and light chain stereotypy. These cell lines use IGHV and IGLV genes that are known to be preferentially rearranged in mantle cell lymphoma, but we found no evidence of heavy chain stereotypy. In contrast, one cell line (Mino) showed a nearly identical light chain complementarity-determining region 3 when compared to the only published light chain cluster. Two cell line couples (Jeko-1/UPN-2 and JVM-2/JVM-13) showed a highly similar light chain that satisfied the criteria for stereotypy. Our data show that mantle cell lymphoma cell lines resemble the IGHV and IGLV usage of mantle cell lymphoma, and foster the hypothesis that light chain stereotypy might be under-recognized. [ABSTRACT FROM AUTHOR]

Death receptor (DR3) 3 is a member of the TNFR superfamily. Its ligand is TNF-like ligand 1A (TL1A), a member of the TNF superfamily. TL1A/DR3 interactions have been reported to modulate the functions of T cells, NK, and NKT cells and play a crucial role in driving inflammatory processes in several T-cell-dependent autoimmune diseases. However, TL1A expression and effects on B cells remain largely unknown. In this study, we described for the first time that B cells from human blood express significant amounts of DR3 in response to B cell receptor polyclonal stimulation. The relevance of these results has been confirmed by immunofluorescence analysis in tonsil and spleen tissue specimens, which showed the in situ expression of DR3 in antigen-stimulated B cells in vivo. Remarkably, we demonstrated that TL1A reduces B-cell proliferation induced by anti-IgM-antibodies and IL-2 but did not affect B-cell survival, suggesting that TL1A inhibits the signal(s) important for B-cell proliferation. These results revealed a novel function of TL1A in modulating B-cell proliferation in vitro and suggest that TL1A may contribute to homeostasis of effector B-cell functions in immune response and host defense, thus supporting the role of the TL1A/DR3 functional axis in modulating the adaptive immune response. [ABSTRACT FROM AUTHOR]

Anaplastic large-cell lymphomas (ALCLs) are a group of clinically and biologically heterogeneous diseases including the ALK+ and ALK- systemic forms. Whereas ALK+ ALCLs are molecularly character-ized and can be readily diagnosed, spe-cific immunophenotypic or genetic fea-tures to define ALK- ALCL are missing, and their distinction from other T-cell non-Hodgkin lymphomas (T-NHLs) re-mains controversial. In the present study, introduction we undertook a transcriptional profiling meta-analysis of 309 cases, including ALCL and other primary T-NHL samples. Pathway discovery and prediction analyses defined a minimum set of genes capable of recognizing ALK- ALCL. Application of quantitative RT-PCR in independent datasets from cryopreserved and formalin-fixed paraffin-embedded samples validated a 3-gene model (TNFRSF8, BATF3, and TMOD1) able to successfully separate ALK- ALCL from peripheral T-cell lymphoma not otherwise specified, with overall accuracy near 97%. In conclusion, our data justify the possi-bility of translating quantitative RT-PCR protocols to routine clinical settings as a new approach to objectively dissect T-NHL and to select more appropriate therapeutic protocols. [ABSTRACT FROM AUTHOR]

Background: Mantle cell lymphoma (MCL) is currently an incurable entity, and new therapeutic approaches are needed. We have applied a high-throughput phospho-proteomic technique to MCL cell lines to identify activated pathways and we have then validated our data in both cell lines and tumor tissues. Methods: PhosphoScan analysis was performed on MCL cell lines. Results were validated by flow cytometry and western blotting. Functional validation was performed by blocking the most active pathway in MCL cell lines. Results: PhosphoScan identified more than 300 tyrosine-phosporylated proteins, among which many protein kinases. The most abundant peptides belonged to proteins connected with B-cell receptor (BCR) signaling. Active BCR signaling was demonstrated by flow cytometry in MCL cells and by western blotting in MCL tumor tissues. Blocking BCR signaling by Syk inhibitor piceatannol induced dose/time-dependent apoptosis in MCL cell lines, as well as several modifications in the phosphorylation status of BCR pathway members and a collapse of cyclin D1 protein levels. Conclusion: Our data support a pro-survival role of BCR signaling in MCL and suggest that this pathway might be a candidate for therapy. Our findings also suggest that Syk activation patterns might be different in MCL compared to other lymphoma subtypes. [ABSTRACT FROM AUTHOR]

Background: A possible association between human cytomegalovirus (HCMV) infection and colorectal cancer progression has been inferred by the identification in tumour tissues of HCMV antigens and specific viral DNA or RNA sequences. To further investigate the relationship between HCMV and colorectal cancers we developed qualitative and quantitative PCR assay to detect HCMV DNA in 56 formalin-fixed paraffin-embedded (FFPE) tissue samples from patients belonging to 4 different histological phenotypes: adenoma; poorly, moderately and well differentiated adenocarcinomas. Results: Of the 56 FFPE tested tissue samples, 6 (11%) were positive for HCMV nested PCR amplification, and more precisely 1 (5%) of 20 cases of adenoma and 5 (21%) of 24 cases of moderately differentiated adenocarcinoma. No PCR positivity was obtained in samples from well and poorly differentiated adenocarcinomas. Conclusion: Our observations suggest that there is no evidence of a direct association between HCMV and colorectal cancer. Moreover, the results obtained are not supportive of a causal role of HCMV in the processes of carcinogenesis and/or progression of colorectal cancer. However, the fact that the virus may present a "hit and run" like-mechanism and HCMV can thus only be detectable at a particular stage of a processing adenocarcinoma, suggests that a significant number of colorectal cancers might have been the subject of HCMV infection that could contribute to trigger the oncogenic differentiation. Our analysis does not exclude the possibility of HCMV infection subsequent viral clearance. [ABSTRACT FROM AUTHOR]

Lipoblastoma is a rare benign mesenchymal neoplasm that typically occurs in infancy but may also occur in older age groups and various locations. Thus, there are often numerous clinical differential diagnoses. Moreover, lipoblastomas can show a broad histologic spectrum, which can hamper the correct diagnosis, particularly in small biopsies. At the genomic level, lipoblastomas are characterized by chromosomal fusions involving the PLAG1 gene. We investigated 11 lipoblastoma samples from 10 pediatric patients (age range five months to 12 years), including one patient with local recurrence, in view of their histopathological features, and performed targeted RNA sequencing. We found a broad histological spectrum with some tumors with prominent myxoid changes, but also tumors composed mainly of mature adipocytic cells, and classified the cases according to the literature as classic (mixed), maturing, or myxoid subtype. By targeted RNA sequencing analysis, we identified characteristic PLAG1 rearrangements in 70% of the investigated cases. Moreover, these analyses revealed three novel gene fusions, two affecting the PLAG1 gene and one involving HMGA2. Besides, we performed PLAG1 immunohistochemistry and identified positive cells, typically immature adipocytic cells and spindle cells, at various numbers in all cases. However, in the maturing areas, only very sparsely positive cells were found, limiting the value of the PLAG1 immunohistochemistry as an adjunct in the diagnosis of lipoblastoma, particularly for the maturing subtype and small biopsies. The presented case series confirms the broad morphological spectrum of lipoblastoma described in the literature and underlines the value of modern molecular diagnostic approaches as a supportive diagnostic tool in challenging cases and for gaining further insights into the molecular basis of this rare mesenchymal tumor. [ABSTRACT FROM AUTHOR]

In vitro Omics analysis (i.e. transcriptome) is suggested to predict in vivo toxicity and adverse effects in humans, although the causal link between high-throughput data and effects in vivo is not easily established. Indeed, the chemical-organism interaction can involve processes, such as adaptation, not established in cell cultures. Starting from this consideration we investigate the transcriptomic response of immortalized thyrocytes to ethylenthiourea and chlorpyrifos. In vitro data revealed specific and common genes/mechanisms of toxicity, controlling the proliferation/survival of the thyrocytes and unrelated hematopoietic cell lineages. These results were phenotypically confirmed in vivo by the reduction of circulating T4 hormone and the development of pancytopenia after long exposure. Our data imply that in vitro toxicogenomics is a powerful tool in predicting adverse effects in vivo, experimentally confirming the vision described as Tox21c (Toxicity Testing in the 21st century) although not fully recapitulating the biocomplexity of a living animal. [ABSTRACT FROM AUTHOR]