Search

S100A4 protein is expressed in fibroblasts during tissue remodelling and in cancer stem cells and it induces the metastatic spread of tumor cells. In mast cells (MCs) S100A4 have been found in some pathological conditions, but its function in normal MCs remains to be described. The purpose of this study was to characterize the cellular localization of the S100A4 protein in MCs of human tissues with inflammatory or tumor disorders and, to determine the consequence of reducing its expression in MC response. We found that tissue resident MCs stained positive to S100A4. Both human HMC-1 cell line and resting CD34+-derived MCs expressed S100A4, whose levels were differentially modulated upon MC activation. Downregulation of the S100A4 protein resulted in MC growth inhibition, enhanced apoptosis and deregulation of MMP-1 and MMP-10 production. Our results suggest that S100A4 is also playing a role in the MC life cycle and functions.

Acute lymphoblastic leukemia (ALL) is the most common hematologic malignancy in children, characterized by an abnormal proliferation of immature lymphoid cells. Thanks to risk-adapted combination chemotherapy treatments currently used, survival at 5 years has reached 90%. ALL is a heterogeneous disease from a genetic point of view: patients’ lymphoblasts may harbor in fact several chromosomal alterations, some of which have prognostic and therapeutic value. Of particular importance is the translocation t(9;22)(q34;q11.2) that leads to the formation of the BCR-ABL1 fusion gene, encoding a constitutively active chimeric tyrosine kinase (TK): BCR-ABL1 that is present in ~3% of pediatric ALL patients with B-immunophenotype and is associated with a poor outcome. This type of ALL is potentially treatable with specific TK inhibitors, such as imatinib. Recent studies have demonstrated the existence of a subset of BCR-ABL1 like leukemias (~10-15% of Bimmunophenotype ALL), whose blast cells have a gene expression profile similar to that of BCR-ABL1 despite the absence of t(9;22)(q34;q11.2). The precise pathogenesis of BCR-ABL1 like ALL is still to be defined, but they are mainly characterized by the activation of constitutive signal transduction pathways due to chimeric TKs different from BCR-ABL1. BCR-ABL1 like ALL patients represent a group with unfavorable outcome and are not identified by current risk criteria. In this review, we will discuss the design of targeted therapy for patients with BCR-ABL1 like ALL, which could consider TK inhibitors, and discuss innovative approaches suitable to identify the presence of patient’s specific chimeric TK fusion genes, such as targeted locus amplification or proteomic biosensors.

// Margherita Perricone 1 , Francesca Palandri 1 , Emanuela Ottaviani 1 , Mario Angelini 2 , Laura Bagli 3 , Enrica Bellesia 4 , Meris Donati 5 , Donato Gemmati 6 , Patrizia Zucchini 7 , Stefania Mancini 8 , Valentina Marchica 9 , Serena Trubini 10 , Giovanna De Matteis 11 , Silvia Di Zacomo 12 , Mose Favarato 13 , Annamaria Fioroni 14 , Caterina Bolzonella 15 , Giorgia Maccari 16 , Filippo Navaglia 17 , Daniela Gatti 18 , Luisa Toffolatti 19 , Linda Orlandi 20 , Veronique Laloux 21 , Marco Manfrini 1 , Piero Galieni 2 , Barbara Giannini 3 , Alessia Tieghi 4 , Sara Barulli 5 , Maria Luisa Serino 6 , Monica Maccaferri 7 , Anna Rita Scortechini 8 , Nicola Giuliani 9 , Daniele Vallisa 10 , Massimiliano Bonifacio 11 , Patrizia Accorsi 12 , Cristina Salbe 13 , Vinicio Fazio 14 , Milena Gusella 15 , Eleonora Toffoletti 16 , Marzia Salvucci 3 , Mirija Svaldi 18 , Filippo Gherlinzoni 19 , Francesca Cassavia 20 , Francesco Orsini 20 , Giovanni Martinelli 1 1 Department of Experimental, Diagnostic and Specialty Medicine, Institute of Hematology ‘L. and A. Seragnoli’, University of Bologna, S. Orsola-Malpighi Hospital, Bologna, Italy 2 Molecular Hematology Laboratory U.O.C of Hematology Hospital Mazzoni, Ascoli Piceno, Italy 3 Medical Genetics Unit- Hub Laboratory AUSL Romagna, Pievesestina di Cesena, Italy 4 Imaging and Laboratory Diagnostic Department, Clinical Chemistry and Endocrinology Laboratory, Hematology Unit, Oncology and Technology Department, Hospital S. Maria Nuova, IRCCS, Reggio Emilia, Italy 5 Clinical Pathology Laboratory, A.O. Ospedali Riuniti Marche Nord, Pesaro, Italy 6 Center Hemostasis and Thrombosis, Section of Medical Biochemistry, Molecular Biology and Genetics, Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy 7 Department of Medical and Surgical Sciences, Division of Hematology, University of Modena and Reggio Emilia, Modena, Italy 8 Clinical Hematology Laboratory, Department of Molecular and Clinical Sciences, Polytechnic University of Marche, Ancona, Italy 9 Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy 10 Clinical Pathology, Molecular Biology Laboratory, and Hematology/Bone Marrow Transplantation Unit, AUSL Piacenza, Piacenza, Italy 11 Section of Clinical Biochemistry and Section of Hematology, Azienda Ospedaliera Universitaria Integrata di Verona, Verona, Italy 12 Department of Hematology, Blood Bank and Biotechnology, Ospedale Civile Pescara, Pescara, Italy 13 UOS Molecular Diagnostics, Department of Clinical Pathology, ULSS12 Venetian, Venice, Italy 14 UOC laboratory medicine, P.O. San Salvatore, Sulmona, L’Aquila, Italy 15 Department of Oncology, Laboratory of Pharmacology and Molecular Biology, ULSS 18, Rovigo, Italy 16 Clinical Hematology, Department of Experimental and Clinical Medical Sciences, University of Udine, Udine, Italy 17 Department of Laboratory Medicine, University-Hospital of Padova, Padova, Italy 18 Department of Haematology and BMT, Healthcare Company of South Tyrol, District of Bolzano, Bolzano, Italy 19 Department of Pathology and Haematology, Treviso General Hospital, Treviso, Italy 20 Werfen, Milano, Italy 21 QIAGEN GmbH, Hilden, Germany, member of the European LeukemiaNet (ELN) Foundation Circle Correspondence to: Margherita Perricone, email: margherita.perricon2@unibo.it Keywords: JAK2 V617F mutation, myeloproliferative neoplasms, qPCR standardization, molecular diagnosis Received: November 01, 2016 Accepted: February 22, 2017 Published: March 06, 2017 ABSTRACT To date, a plenty of techniques for the detection of JAK2 V617F is used over different laboratories, with substantial differences in specificity and sensitivity. Therefore, to provide reliable and comparable results, the standardization of molecular techniques is mandatory. A network of 19 centers was established to 1) evaluate the inter- and intra-laboratory variability in JAK2 V617F quantification, 2) identify the most robust assay for the standardization of the molecular test and 3) allow consistent interpretation of individual patient analysis results. The study was conceived in 3 different rounds, in which all centers had to blindly test DNA samples with different JAK2 V617F allele burden (AB) using both quantitative and qualitative assays. The positivity of samples with an AB < 1% was not detected by qualitative assays. Conversely, laboratories performing the quantitative approach were able to determine the expected JAK2 V617F AB. Quantitative results were reliable across all mutation loads with moderate variability at low AB (0.1 and 1%; CV = 0.46 and 0.77, respectively). Remarkably, all laboratories clearly distinguished between the 0.1 and 1% mutated samples. In conclusion, a qualitative approach is not sensitive enough to detect the JAK2 V617F mutation, especially at low AB. On the contrary, the ipsogen JAK2 MutaQuant CE-IVD kit resulted in a high, efficient and sensitive quantification detection of all mutation loads. This study sets the basis for the standardization of molecular techniques for JAK2 V617F determination, which will require the employment of approved operating procedures and the use of certificated standards, such as the recent WHO 1st International Reference Panel for Genomic JAK2 V617F .

A defective switching off of the immune response is involved in several autoimmune diseases. This switching off involves Fas-mediated apoptosis, perforin-mediated fratricide of activated lymphocytes, and the suppressive activity of regulatory T (Treg) cells. These mechanisms are altered in autoimmune lymphoproliferative syndrome that often displays autoimmune thrombocytopenia. The aim of this research was to evaluate these mechanisms in adult patients with primary immune thrombocytopenia (ITP), compared with healthy controls. The results show that a substantial subgroup of the ITP patients displayed a defective Fas function; most of them displayed decreased Fas expression in T cells activated in vitro. Moreover, ITP patients displayed an increased frequency of rare missense variations of the PRF1 gene and decreased levels of Treg. Immunological analysis showed that levels of Interleukin (IL)10 and IL17 were decreased and marginal zone B cells were increased. Moreover, myeloid and plasmacytoid dendritic cells were decreased in ITP patients. In conclusion, in adult ITP patients, several mechanisms involved in shutting off the immune response are defective and several immunological parameters are dysregulated; these alterations may play a role in the clinical heterogeneity of the disease.

The analyses carried out using 2 different bioinformatics pipelines (SomaticSniper and MuTect) on the same set of genomic data from 133 acute myeloid leukemia (AML) patients, sequenced inside the Cancer Genome Atlas project, gave discrepant results. We subsequently tested these 2 variant-calling pipelines on 20 leukemia samples from our series (19 primary AMLs and 1 secondary AML). By validating many of the predicted somatic variants (variant allele frequencies ranging from 100% to 5%), we observed significantly different calling efficiencies. In particular, despite relatively high specificity, sensitivity was poor in both pipelines resulting in a high rate of false negatives. Our findings raise the possibility that landscapes of AML genomes might be more complex than previously reported and characterized by the presence of hundreds of genes mutated at low variant allele frequency, suggesting that the application of genome sequencing to the clinic requires a careful and critical evaluation. We think that improvements in technology and workflow standardization, through the generation of clear experimental and bioinformatics guidelines, are fundamental to translate the use of next-generation sequencing from research to the clinic and to transform genomic information into better diagnosis and outcomes for the patient.

Recent evidence concerning the cellular pathway of idiopathic thrombocytopenic purpura (ITP) indicate a strict relationship between T and B-cells. T-cell deregulation, probably antigen driven, results in an increase of the CD4 Th1/Th2 ratio with oligoclonal CD4 expansion. According to this model, B

Abstract 3291 Primary immune thrombocytopenia (PIT) results from both increased platelet destruction and insufficient platelet production. Although the development of autoantibodies against platelet glycoproteins remains central in the pathophysiology of PIT, several abnormalities in the immune modulation system have been identified (Blood 2008 Aug 15;112(4):1147; Hematol Oncol Clin North Am. 2009 Dec;23(6):1177; Hum Immunol. 2010 Jun;71(6):586); We analysed morphology, lymphocyte phenotype and heavy immunoglobulin (IgH) and TCR gamma (TCRg) gene rearrangements in spleens from 31 PIT patients to assess possible impact on diagnosis and course, in comparison with 19 spleens surgically removed for trauma. Age ranged from 15 to 68 (mean 41.61y) with M/F of 9/22 in PIT and 18 to 89 (mean: 66y) with M/F 11/8 in controls. All PIT patients experienced at least one line therapy before surgery and 4 underwent anti-CD20 immunotherapy. Immunohistochemistry for CD3, CD20, CD4, CD8, CD56, CD57, PD1, Tia1, Granzyme B, FoxP3, CD72 was made in all cases; both IgH and TCRg gene analysis were possible in 24/31 PIT and 17/19 controls, while 4/31 PIT and 2/19 controls were examined for either one (PIT: 2 TCR and 2 IgH, controls 1 TCR and 1 IgH) and 5 PIT and 1 control were excluded for unsatisfactory material. Ay histology all cases but 2 showed expanded white pulp (that was hypoplastic in the 2/4 cases that underwent Rituximab before surgery), moderate lymphocytic and modest granulocytic infiltrates in the red pulp; haemorragic lakes were present in control spleens. Immunohistochemistry showed similar stains in the 2 groups with normal distribution (white pulp: CD20+ B follicles, CD72-+ in the marginal zone, CD3+/CD4+ T cells, PD1/CD57+ T cells in the germinal centers; red pulp: regular CD20/CD3 and CD4/CD8 ratio, PD1/Tia1/Granzyme B expressed in roughly less than 20% CD3+ T cells; scattered CD57+/CD56- T cells. For molecular results see table 1 below. Monoclonality was defined if 1 or 2 peaks of amplified polymerase chain reaction products were obtained, oligoclonality with 3 to 5 peaks and polyclonality with a Gaussian peak distribution.Table 1IGHWDCtrlIGHWDCtrlPoly2015Poly-Oligo2116Oligo10Mono32Mono32TCRWDCtrlTCRWDCtrlPoly75Poly-Oligo128Oligo53Mono129Mono129 The results showed no statistically significant differences between PIT and controls as for morphology, phenotype and clonality. Since a decrease in regulatory T cells (T regs) is reported in PIT among other immune-impairments (Eur J Haematol. 2007 Oct;79(4):310; Zhonghua Nei Ke Za Zhi. 2010 Mar;49(3):213;Blood. 2009 Mar 12;113(11):256) we immunostained all cases with T reg-related nuclear molecule Foxp3: in control cases few cells in the white and red pulp were observed, while in PIT spleens fewer Foxp3 positive cells could only be seen in the red pulp: although results are slightly different, the low amount of positive cells in both groups decreases the reliable reproducibility of such observation. Moreover, the use of glucocorticoids by all patients before splenectomy, could have further reduced (Eur J Haematol. 2007 Oct;79(4):310) T regs levels. Overlapping molecular results were also obtained in the two groups in agreement with previous reports (Hematology. 2009 Aug;14(4):237; Platelets. 2009 Mar;20(2):135; Int J Hematol. 2003 Dec;78(5):461; Blood. 2002 Aug 15;100(4):1388). The attempt to translate the molecular findings into immunomorphologic differences between monoclonal and non monoclonal cases failed since neither amount/distribution of B and T cells nor T cell subtypes showed evident differences. On the whole, our results show that neither lymphoid phenotype nor IgH or TCRg clonality can be used as specific features of refractory PIT or guide treatment choice.Figure 1Figure 1. Disclosures: No relevant conflicts of interest to declare.