bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of Circulating t(14;18)-Positive Cells in 4152 Individuals without Lymphoma Shows Association with Age and Gender, but Not with Smoking Status: Results From the Population-Based Study of Health in Pomerania (SHIP).
Authors: Hirt Carsten , Weitmann Kerstin , Schueler Frank , Späth Christian , Hoffmann Wolfgang , Doelken Gottfried 
Published: October 2019

Abstract
Abstract 3921
Poster Board III-857
The t(14;18)(BCL2/IgH) translocation is the genetic hallmark of follicular lymphoma (FL). Circulating t(14;18)-positive cells can not only be detected in FL patients but also in healthy subjects without lymphoma. Several epidemiological and molecular studies suggest that these t(14;18)-positive cells might represent lymphoma precursor cells and are associated with known FL risk factors like age and geographical differences in lymphoma incidence. We used epidemiological data and blood samples of a population-based study to verify associations of FL risk factors and t(14;18)-positive cells reported so far and to test for new associations.
The study of health in Pomerania (SHIP) collects epidemiological data, a basic health status and blood samples from 4310 randomly selected inhabitants of the study region in the northeastern part of Germany. We tested buffy coat-DNA samples from 4152 study participants (median age 50 years, range 20-81 years, 2100 women) by real-time PCR for the presence and frequency of t(14;18)-positive cells.
t(14;18)-PCR results were evaluable from 2620 subjects, 1533 subjects were tested positive (58.1%, median number of t(14;18)-positive cells in positive subjects 3.9 per million nucleated cells, range 0.6 – 9299 per million nucleated cells). t(14;18)-prevalence was lowest in the age group 20-29 years (42.2%) and increased up to the group 50-59 years (67.0%) but did not further increase up to the age of 81 years. In accordance with previous reports there was a significant increase of the t(14;18)-frequency with age up to the age of 69 years (linear regression, p< 0.0001) in this study. In the SHIP cohort, t(14;18)-prevalence was lower in females compared to males (53.2% versus 63.5%, p< 0.0001), but there was no significant difference in t(14;18)-frequency between males and females. Smoking status (current, former and never smoker) had no influence on t(14;18)-prevalence or frequency.
This study confirms the association of t(14;18)-prevalence with age and shows for the first time that the t(14;18)-prevalence in females is lower than in males. The later finding parallels the observation of a lower FL incidence in females. In contrast to previous studies, smoking was not associated with detection of t(14;18)-positive cells when the analysis was adjusted for age and sex. In summary, this study confirms that the prevalence of t(14;18)-positive cells in non-lymphoma subjects is associated with established FL risk factors. Thus our report adds to the accumulating evidence that circulating t(14;18)-positive cells in non-lymphoma subjects may represent a biomarker of FL risk.

Disclosures:
No relevant conflicts of interest to declare.
Junctional Adhesion Molecule C (JAM-C) Constitutes a New Marker for the Differential Diagnosis of B Cell Lymphomas.
Authors: Matthes Thomas , Ody Christiane , Imhof Beat , Donate Carmen , Cossali Dominique , Ruault Sylvie , Kern Wolfgang 
Published: October 2019

Abstract
Abstract 3940
Poster Board III-876

Introduction
Differentiation of naïve B cells into plasma cells or memory cells occurs in the germinal centres (GC) of lymph follicles or alternatively in the marginal zone via a GC- and T cell independent pathway. It is currently assumed that B cell lymphomas correspond to normal B cell differentiation stages, but the precise correlation of several B cell lymphomas to these two pathways remains controversial. We have previously shown that junctional adhesion molecule C (JAM-C) originally identified at the cell-cell border of endothelial cells, constitutes also a marker of B lymphocytes with a tightly regulated expression during B cell differentiation: immature B cells, GC-B cells and plasma cells stain negatively, whereas mature, memory and marginal zone derived B cells stain strongly positive. Here we test the expression of JAM-C on a series of patients with B cell lymphomas.

Methods
B lymphocytes from the peripheral blood of 158 untreated patients were analyzed using flow cytometry with standard antibody panels (CD5, CD10, CD11c, CD22, CD23, CD25, CD38, CD103, FMC7, sIg). Diagnosis of a B cell lymphoma was established according to WHO guidelines, using additionally RT-PCR, karyotyping, or FISH, if necessary. Expression of JAM-C was studied by flow cytometry with a polyclonal antibody obtained from a rabbit immunized with the soluble JAM-C molecule.

Results
MCL, HCL and MZBL with a supposed origin in the marginal zone stained mostly positive, whereas CLL and FL with a supposed origin in the germinal centre showed mostly a negative staining. No correlation was found in CLL between JAM-C expression and staining for ZAP70 or CD38. In 12 cases routine work-up was not able to precisely establish a diagnosis of CLL or MZBL, and CLL or MCL. In these cases the presence of JAM-C was considered a strong argument against a GC-origin of the malignant B cells. Addition of JAM-C to antibodies used in the Matutes score increased the sensitivity and specificity of this score for the diagnosis of CLL. Furthermore, it may help differentiating MZBL from LPL which otherwise display overlapping immunophenotypes.

Conclusion
JAM-C constitutes a new diagnostic marker for the differential diagnosis of B cell lymphomas, and is particularly useful for the distinction between CLL and LPL (negative staining) on the one hand and mantle cell and marginal zone B cell lymphomas (positive staining) on the other hand.

Disclosures:
No relevant conflicts of interest to declare.
Sezary Syndrome Is a Malignancy of Central Memory T Cells with Skin Homing Properties, While Mycosis Fungoides Is a Malignancy of Skin Homing Effector Memory T Cells.
Authors: Campbell James , Clark Rachael A , Kupper Thomas S. 
Published: October 2019

Abstract
Abstract 3954
Poster Board III-890
The relationship between leukemic CTCL (L-CTCL), which includes Sezary Syndrome (SS), and mycosis fungoides (MF), a CTCL variant characterized by infiltration of skin, is incompletely understood. In the present study, we examined skin and/or peripheral blood from more than 300 patients with diagnoses of CTCL accrued over a five year period. We identified a subset of patients with leukemic CTCL, all of whom had absolute CD4 counts >2000, CD4/CD8 ratios of > 10, and other features of SS (loss of CD7 and/or CD26). Using specific TCR-Vb antibodies, we could identify malignant clonal populations from CD4+/CD8- peripheral blood mononuclear cells of 12 L-CTCL patients, and performed comprehensive analysis of the malignant clones by flow cytometry. With regard to skin-associated trafficking markers, we found consistently high CCR4 expression, but very heterogeneous expression of CCR6, CCR10 and CLA. Lymph-node homing molecules CCR7 and L-selectin were consistently expressed at high levels on the malignant clonal cells. CD45RA-to-CD45RO ratios, which typically distinguish between non-malignant naïve and antigen-experienced CD4 T cells, were unexpectedly variable from patient to patient. However, CD27, whose expression is lost in normal T cells upon effector/memory cell differentiation, was highly expressed by all malignant clonal cells in SS/L-CTCL. We compared this pattern to the expression of homing and maturation markers on malignant cells extracted from lesional skin of patients with MF. These cells reliably expressed CLA and CCR4, but expressed very low levels of CCR7 and L selectin. In addition, they expressed low levels of CD27. Based on this evidence, L-CTCL/SS appears to be a T central-memory cell CD4-lymphocyte malignancy that, with the exception of CCR4, has variable expression of the putative skin-homing markers CLA, CCR6, or CCR10. This is in direct contrast to MF, wherein clonal T cells in lesional skin bear uniform expression of some skin-homing markers but low expression of central memory markers. These data support a growing body of evidence that SS/L-CTCL and MF are fundamentally different malignancies, rather than different clinical stages of a single disease.

Disclosures:
No relevant conflicts of interest to declare.
Simultaneous Detection of BCL2 Translocation and Copy Number Alteration Including Intrachromosomal Amplification in FL and DLBCL.
Authors: Chhabra Harinder , Mizhiritskay Valentina , Barnabe Charles , Montella Lya Josephine , Nelson Viera , Sun Guoxian 
Published: October 2019

Abstract
Abstract 3955
Poster Board III-891
Causal overexpression of BCL2 protein in follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) can be deregulated either by chromosome translocation t(14;18)(q32;q21) or by copy number increase (CNI) of the BCL2 gene, the latter of which includes gains of 18q and extra- or intra-chromosomal amplification. To study the utilization and advantages of interphase fluorescence in situ hybridization (FISH) testing, we retrospectively analyzed abnormal results from 226 consecutive cases with FL or DLBCL using a dual-color dual-fusion t(14;18)/IGH-BCL2 probe (Abbott, IL) performed on various types of specimens such as paraffin embedded tissue, lymph nodes and bone marrow aspirates. The t(14;18) was found in 133 cases (58.8%) with 5 of them also having one extra BCL2 signal, whereas the remaining 93 (41.2%) cases had increased copy number of BCL2 with a range of 3 to 60. In the CNI group, there were two patterns observed: scattered signals seen in the vast majority of cases; and large clusters of intrachromosomally amplified signals observed in two cases. In a concurrent metaphase cytogenetic analysis on the same tonsil sample in one patient with DLBCL, the amplified BCL2-containing segments were present as homogeneously staining region (hsr) on chromosome 13q as well as 18q with no double minutes or marker chromosomes detected. The second highly amplified case was incidentally found to have enlarged lymph nodes during vascular surgery and diagnosed as follicular lymphoma grade 1/3. Interestingly, FISH on paraffin embedded lymph nodes showed one large cluster of amplified BCL2 with an IGH signal within each cluster, suggesting a coexisting translocation t(14;18) and an amplification of BCL2 per se. The FISH patterns in these two highly amplified cases seem to represent a tandem duplication of the BCL2 gene. Although t(14;18) and BCL2 amplification are generally considered to be mutually exclusive in lymphomagenesis, our latter case may be the first reported one where t(14;18) and BCL2 amplification occurred concomitantly. Our study demonstrated that FISH testing with its high specificity, sensitivity and easy visibility for individual cells from various tissue types can simultaneously detect translocations and copy number alterations, provide valuable diagnostic/prognostic information in lymphoma stratification, and complement conventional cytogenetics and comparative genomic hybridization.

Disclosures:
No relevant conflicts of interest to declare.
Kinase Activity of RTKs Is Dispensable for Factor Independent Growth and Transformation of a Myeloid Cell Line 32D in the Presence of Cbl Mutants.
Authors:   Bülent Sargin on behalf of the Study Alliance Leukemias (SAL), Bandi Srinivasa Rao , Rensinghoff Marion , Grundler Rebekka , Tickenbrock Lara , Duyster Justus , Berdel Wolfgang E , Brandts Christian , Serve Hubert , Müller-Tidow Carsten 
Published: October 2019

Abstract
Abstract 3970
Poster Board III-906

Purpose
The Cbl proto-oncogene products have emerged as important components of the signal transduction cascades downstream of both non-receptor and receptor tyrosine kinases (RTKs). By regulation of receptor trafficking and degradation, they have been shown to tightly regulate the intensity and amplitude of RTK activation. c-Kit belongs to the family of the class-III RTKs and plays an important role in the pathogenesis of acute myeloid leukemia (AML). So far, very little is known about the role of c-Cbl mutants in the role of c-Kit signaling.

Results
We analyzed the interaction of c-Cbl with c-Kit and the functional relevance of this interaction in the IL-3-dependent murine myeloid progenitor cell line 32Dcl3. We recently identified the first c-Cbl mutation in human disease in an AML patient, named Cbl-R420Q. Co-expression of two different dominant negative mutants of c-Cbl (Cbl-R420Q or Cbl-70Z) with Kit induced cytokine-independent proliferation, survival and clonogenic growth. Importantly, transformation was observed also with kinase-dead forms of Kit and Flt3 in the presence of Cbl-70Z, but not in the absence of Kit or Flt3, suggesting a mechanism dependent on RTKs, but independent of their kinase activity. Instead, transformation appeared to depend on Src family kinases (SFKs), as c-Cbl co-immunoprecipitated with SFKs and SFK inhibition abolished transformation.

Conclusion
Our results indicate that c-Cbl has an important role in c-Kit signal mitigation. They demonstrate that disturbed mechanisms of c-Kit internalization have important implications for its transforming potential, possibly in the development of AML. Furthermore, these findings may explain primary resistance to tyrosine kinase inhibitors targeted at RTKs.

Disclosures:
No relevant conflicts of interest to declare.
Loss of Tnk1/Kos1 in Mice Is Associated with B-Lymphomas Specifically DLBCL.
Authors: Hoare Kishalay , Reinhard Mary K , Hoare Sarasija , Flagg Tammy , May W. Stratford 
Published: October 2019

Abstract
Abstract 3972
Poster Board III-908
The ubiquitously expressed nonreceptor tyrosine kinase (NRPTK) Tnk1/Kos1 (Thirty-eight negative kinase/Kinase of the embryonic stem cell) functions as a negative regulator of growth in both murine and human cells by suppressing the Ras-Raf1-MapK growth pathway. Since Tnk1 requires its intrinsic protein tyrosine kinase activity to suppress Ras activity and cell growth, the kinase domain is critical for its function and deletion by targeted homologous recombination leads to spontaneous tumor development in mice. To date, Tnk1/Kos1 is the only reported NRPTK that functions as a tumor suppressor in vivo, while other tyrosine kinases may be oncogenic when mutated or activated. While Tnk1 knockout mice may develop primary tumors in different tissues/organs, mainly B-cell lymphomas develop in Tnk1-/- (80%, 47 of 60) and Tnk1+/- (57%, 31 of 54) mice with similar characteristics of Diffuse Large B-Cell Lymphoma (DLBCL) and Burkitt Lymphoma types. Typically in lymphomas from Tnk1+/- mice the intact wild type allele is epigenetically modified and silenced by promoter methylation. Importantly, the absence of Tnk1 occurs only in the tumor tissue but not in the adjacent uninvolved tissue. Now we find allelic loss with associated reduced expression of Tnk1 transcripts and protein in a cohort of human DLBCL patients. These data underscore the potential clinical relevance of Tnk1 in human hematological malignancies. Furthermore, the B-cell lymphomas that develop in the Tnk1 knockout mice express aberrantly high Ras activity indicating that unmutated Ras is a likely necessary effector of B-cell lymphoma development and survival. We also recently determined that the aberrantly high levels Ras activity in lymphoma (but not paired uninvolved lymphoid tissue) from mice results from a novel mechanism involving stabilization of the Grb2-Sos1 complex to maintain activated Ras in these tissues. Therefore, the Tnk1 knockout mouse provides a unique opportunity to test whether and how Tnk1 is involved in the development and/or maintenance of the B-cell lymphomas that develop in the absence of Ras mutation which may have clinical significance for patients with lymphoma.

Disclosures:
No relevant conflicts of interest to declare.
DECREASED ACTIVITY of ADAMTS13 IN PATIENTS with DEEP Vein Thrombosis.
Authors: de Moraes Mazetto Bruna , Orsi Fernanda A. , Montalvao Silmara Aparecida Lima , Mello Tayana B , de Paula Erich Vinicius , Annichino-Bizzacchi Joyce Maria 
Published: October 2019

Abstract
Abstract 3991
Poster Board III-927

Introduction
Several risk factors, including increased levels of factor VIII (FVIII) and von Willebrand factor (VWF), have already been identified in patients with deep vein thrombosis (DVT). Recently we published a study showing that in a Brazilian population, plasma levels of FVIII over 180U/dl and VWF over 165U/dl were associated with the occurrence of venous thrombosis (odds ratio = 4.1 and 3.8 respectively) (Mello TB et al, 2009). The level of VWF in plasma and consequently FVIII is the result of genetic and acquired factors. ADAMTS13 (ADisintegrin And Metalloprotease with Thrombospondin type 1 repeats) is an enzyme responsible for cleavage of VWF, and its activity could contribute to VWF and FVIII plasmatic levels in patients with DVT.

Objective
To evaluate the activity of ADAMTS13 in patients with DVT associated with an increase of VWF and FVIII. Patients and methods: Fifty-six patients with FVIII > 180U/dl or FVW>165U/dl were selected from a cohort of 175 patients with DVT from the study mentioned above. Fifty-four normal subjects were selected as controls. The activity of ADAMTS 13 was performed by binding of residual VWF to collagen; VWF activity was measured by collagen binding, VWF antigen was determined by ELISA and FVIII was measured by a one-stage coagulation assay. Continuous variables were analyzed by Mann-whitney test and categorical variables by the Chi-square test.

Results
The demographic distribution of patients and controls were similar. Among the 56 patients the median age was 37.5 years, 39 were women, 46 had blood typing “non-O”, 34 had DVT caused by transient risk factor, especially the use of oral contraceptives, 10 patients had a hereditary thrombophilia and 3 were carriers of antiphospholipid antibodies. No patient had renal, hepatic or malignant disease. The median ADAMTS 13 activity was significantly lower in patients (112.9%, 44.4 - 327.6%) when compared to controls (142.9%, 76.7 - 323.6%), P = 0.001. The VWF activity was also higher in patients (109.7%, 26.8 - 422.6%) when compared to controls, (79.1%, 45.5 - 203.8%), P=0.038. The median level of VWF antigen was significantly higher in the group of patients when compared to the control group (178.1U/dl versus 111.9 U/dl respectively, P <0.0001). There was an inverse correlation between ADAMTS13 activity and VWF activity. Conclusion: This study suggests that the increased VWF and FVIII activity in patients with DVT can be a result of decreased ADAMTS13 activity. The decreased activity of ADAMTS13 may be influenced by the action of cytokines in inflammatory processes, even after acute period. Future studies will be important to determine the correlation between activity of ADAMTS 13, VWF, and inflammatory markers in the pathogenesis of DVT.

Disclosures:
No relevant conflicts of interest to declare.
Expression of Apoptosis Repressor with Caspase Recruitment Domain (ARC), An Antiapoptotic Protein, Is Strongly Prognostic in Acute Myeloid Leukemia (AML).
Authors: Carter Bing Z. , Zhang Nianxiang , Coombes Kevin R. , Mak Duncan H. , Qiu YiHua , Thomas Deborah A. , Ravandi Farhad , Kantarjian Hagop , Andreeff Michael , Kornblau Steven M. 
Published: October 2019

Abstract
Abstract 400

The identification of relevant targets to induce apoptosis and sensitize to chemotherapy is a focus in AML research. Reverse-phase protein array (RPPA) is a validated and robust proteomic system which can quantitatively determine protein expression and facilitate the selection of molecular-targeted therapies. ARC, located on chromosome 16q21-q23, is an antiapoptotic protein. It inhibits both the intrinsic and extrinsic apoptosis pathways by suppressing the activity of caspase-2 and -8 and by blocking Bax activation. ARC also negatively regulates p53 by inhibiting its tetramerization and triggering its cytoplasmic localization and degradation of ARC depends on the p53-induced ubiquitin E3 ligase, MDM2. ARC has only recently been demonstrated to be expressed in various cancer cells and to confer both chemo- and radio-resistance. To determine its expression and assess its importance in AML, we profiled ARC expression in 511 newly diagnosed patients with AML using RPPA. Similar levels of ARC expression were found in 140 paired blood and bone marrow samples and no significant difference was detected between diagnosis and relapse in 49 paired samples from the same patients. ARC levels were inversely correlated with the protein levels of Bad (p<0.00001), cleaved caspase-9 (p<0.00001), cIAP1 (p<0.00001), caspase-9 (p<0.00001), XIAP (p<0.00001), and Bcl-2 (p=0.00001). Further, ARC levels are significantly higher in FAB M4 (p<0.00001) and M3 (p=0.012) and lower in FAB M2 (p=0.002) AML, but it is neither associated with favorable, intermediate, or unfavorable cytogenetics nor with FLT-3 mutation status. ARC levels do not correlate with bone marrow blast counts, but shows an inverse correlation with blood blast counts (p<0.00001). Importantly, AML patients with low or mid range ARC protein levels had significantly longer overall survival (Median 53 or 61 vs. 38 weeks, p=0.004, A) and remission duration (Median 75 vs 45 vs 29 weeks, p=0.0008, B) (see the figure below) than patients with high levels of ARC. Multivariate analysis indicated that ARC is a statistically significant independent predictor of survival in AML. The final model included: Gender (p=0.008), age at diagnosis (p<0.00001), cytogenetic groups (p<0.00001), FLT-3ITD (p=0.001), WBC (p<0.00001), platelet (p=0.009), albumin (p=0.00006), and ARC (p=0.00006). Results suggest that the expression levels of ARC are highly prognostic in AML and that ARC could be a potential therapeutic target in AML.

Disclosures:
No relevant conflicts of interest to declare.