bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tonic B-Cell Receptor Signaling Promotes the Survival of Diffuse Large B-Cell Lymphomas: Identification of SYK as a Rational Treatment Target.
Authors: Chen Linfeng , Juszczynski Przemyslaw , Hitoshi Yasumichi , Chen Wen , Kutok Jeffery L. , Shipp Margaret A. 
Published: October 2019

Abstract
The role of BCR-mediated survival signals in diffuse large B-cell lymphoma (DLBCL) remains undefined. B-cell antigen receptor (BCR) signaling induces receptor oligomerization and Ig alpha/beta ITAM phosphorylation. Thereafter, the protein tyrosine kinase (PTK) SYK is recruited and activated, initiating downstream events and amplifying the original BCR signal. Recent studies indicate that BCRs also transmit low-level survival signals in the absence of receptor engagement and highlight the critical role of SYK in this “tonic” BCR signaling. We recently found that SYK is a major substrate of the protein tyrosine phosphatase, PTPROt. PTPROt-mediated dephosphorylation and inactivation of SYK inhibited DLBCL proliferation and induced apoptosis in the absence of BCR cross-linking. These observations suggested that tonic BCR signaling may be an important survival mechanism in certain DLBCLs and identified SYK as a possible rational therapeutic target. For these reasons, we assessed the efficacy of a recently developed ATP-competitive inhibitor of SYK, R406, in a panel of 8 DLBCL cell lines. R406 inhibited the proliferation of 6 DLBCL cell lines at IC50s of 0.9–1.8 micromolar. The SYK inhibitor was cytotoxic (30–85% apoptotic cells) at low micromolar doses in 6 of these lines. To delineate the relationship between tonic BCR signaling, associated SYK activity and R406 responsiveness, we assessed SYK phosphorylation (pTYR 352 and 525/526) in the DLBCL cell line panel. Upon BCR signaling, SYK is phosphorylated at TYR 352; thereafter, the kinase undergoes autophosphorylation at TYR 525/526, which is required for SYK activity. In sensitive DLBCL cell lines, R406 specifically inhibited TYR 525/526 phosphorylation and additional downstream signals (p-ERK). In addition, all 6 R406-sensitive DLBCL cell lines exhibited basal SYK 352 phosphorylation whereas the 2 R406-resistant lines lacked pTyr 352 phosphorylation. Basal SYK pTYR 352 could be detected by immunoblotting total SYK immunoprecipitates with a phospho-specific SYK 352 antibody or using the same pTYR 352 antibody for intracellular phospho-specific flow cytometry. We conclude that :tonic BCR signaling is an important survival mechanism in many DLBCLs;SYK is a rational therapeutic target in these tumors;R406 is a promising SYK inhibitor; andSYK pTYR 352 is an excellent indicator of tonic BCR signaling and predictor of R406 sensitivity in DLBCL.
Bone Marrow Fibrosis Evaluation in Childhood Acute Lymphoblastic Leukaemia: Correlation to Biological Factors and Treatment Response.
Authors: Norén-Nyström Ulrika , Roos Goran , Bergh Anders , Thörn Ingrid , Lonnerholm Gudmar , Forestier Erik 
Published: October 2019

Abstract
Fibrosis may complicate bone marrow (BM) disease and in its advanced stage negatively affect the outcome of the patients due to BM failure, particularly in myeloproliferative disorders. Studies of the potential importance of BM fibrosis are rare in childhood acute lymphoblastic leukemia (ALL). We have previously shown a prognostic impact of BM fibrosis measured as reticulin fibre density (RFD) at diagnosis in childhood ALL. To further investigate the consequence of BM fibrosis in childhood ALL in relation to immunophenotype, cytogenetic findings and minimal residual disease (MRD) we retrospectively evaluated the RFD in 139 diagnostic BM biopsies from patients with a total mean follow up time of five years and eight months from two childhood oncology centers in Sweden. Patients with pre-B-ALL showed a higher mean RFD (19.1%) compared to patients with T-ALL (11.4%, p < 0.001). This was true also when comparing high-risk (HR) pre-B-ALL patients (18.1%) with the T-ALL patients (p = 0.002). RFD correlated inversely with the white blood cell count in the HR group (r = −0.41, p = 0.009), probably reflecting our finding of low degree of fibrosis in T-ALL. The cytogenetic analysis revealed that for patients with a hyperdiploid ALL (modal chromosome number: 51–61, n: 41) in the low-risk (LR) group, mean RFD was higher for relapsed patients (22.6%) compared to patients in continuous complete remission (17.2%, p = 0.019). The probability of disease free survival for the same group using RFD cutoff of 21.1%, representing the upper third of the material, was 85%±8% for patients with hyperdiploid ALL and low RFD compared to 51%±14% for patients with hyperdiploid ALL and high RFD (p = 0.01, Figure 1). Data for 32 of the patients demonstrated an association between high RFD at diagnosis and high minimal residual disease (MRD) on day 29 after start of treatment. Patients with FACS-MRD > 10−3 day 29 displayed higher mean RFD at diagnosis (21.2%) compared to patients with FACS-MRD < 10−3 (16.7%, p = 0.027, Figure 2). When analyzing the PCR-MRD data day 29 the findings were similar. We conclude that RFD is higher in pre-B-ALL compared to T-ALL, that RFD has prognostic impact in LR patients with hyperdiploid ALL and that high RFD at diagnosis is associated to high MRD on treatment day 29. All these findings are to our knowledge novel, suggesting that evaluation of BM fibrosis at diagnosis is a potentially new therapy stratifying factor and support the need of further research on BM fibrosis in childhood ALL and expanded use of BM biopsy at diagnosis.
Figure 1 Figure 1. Figure 2 Figure 2.
Wilm’s Tumour 1 (WT1) Mutations Are Associated with FLT3-ITD Mutation and Poor Prognosis in Normal Karyotype AML.
Authors: Fitzgibbon Jude , Summers Karin , Kakkas Ioannis , Stevens Jane , Smith Matthew , Smith Lan-Lan , Molloy Gael , McDougal Finlay , Bonnet Dominique , Young Bryan D. , Lister T. Andrew 
Published: October 2019

Abstract
Our group has previously shown an association between acquired uniparental disomy 11p and homozygous gene mutation of Wilm’s tumour 1 (WT1) in a patient with normal karyotype acute myeloid leukemia (AML). Based on this observation the incidence of WT1 mutation was investigated in a cohort of normal karyotype AMLs. Mutation screening was performed on 70 patients (median age 55 years, range 19–78 years) by a PCR-direct sequencing approach using intronic primers flanking exons 2–10 of WT1. Mutation status was inferred from the resultant traces and confirmed by use of TOPO TA cloning and sequence analysis of the corresponding mutated clones. Mutations were detected in 7/70 (10%) patients; these typically resulted in insertion of 1–16 bp that led to the disruption of the DNA binding domain of the protein. The mutation profile of FLT3-ITD, NPM and CEBPA was also examined in this cohort of patients to compare the additional mutational events present in WT1 mutated and non-mutated cases. A significant positive association was observed between WT1 and FLT3-ITD mutation with 6/7 WT1 mutated cases having a FLT3-ITD compared to 20/63 non mutated cases (p=0.01). There was no association between mutations in WT1 and either of the good prognostic mutational markers, CEBPA and NPM. All 6 patients with both WT1 and FLT3 mutations were refractory to intensive induction chemotherapy with WT1 mutation showing a trend towards a worse overall survival when compared with the non-mutated group (p=0.07). We can conclude therefore that WT1 is mutated in 10% of normal karyotype AML, is positively associated with FLT3-ITD status and identifies a putative subgroup of normal karyotype AML who fail to achieve remission with conventional cytotoxic therapy and have a poor overall survival. Validation of this data in larger series would support the inclusion of WT1 in the current molecular risk stratification of normal karyotype AML based on CEBPA, NPM and FLT3-ITD status.
Characterisation and Prognostic Significance of WT-1 Gene Expression in Acute Myeloid Leukemia (AML).
Authors: Lane Steven W. , Saal Russell , Negus Suzanne , Mollee Peter , Mather M. , Gill Devinder , Mills Anthony K. , Bird Robert J. , Hourigan Matthew J. , Jones Mark , Marlton Paula 
Published: October 2019

Abstract
Background: Wilms’ tumour gene 1 (WT-1) is frequently over-expressed in adult AML and may be of prognostic value. We examined the prognostic utility of WT-1 expression in the peripheral blood, measured by RQ-PCR on diagnostic specimens, and characterised this compared to other clinical and biological predictors of survival.
Methods: RQ-PCR was performed in triplicate on samples from newly diagnosed AML patients, using the Corbett Rotorgene 3000. Values were averaged and levels expressed relative to 104 ABL copies. Multivariate stratified Cox regression, with the stratification variable cytogenetic risk group and WT-1 levels analysed as a continuous variable, was used to model the outcomes of overall survival (OS) and event free survival (EFS).
Results: Samples were collected from 58 patients with AML. The median age was 66 years (range 16–82) and 30 were male. Seven had antecedent haematological disorders and 9 had received prior chemo/radiotherapy. Induction therapy was with cytarabine based regimens in 18, high dose cytarabine regimens in 20, ATRA/chemotherapy in 6 and supportive care in 14. Complete remission was achieved in 64% with 18% induction mortality. Median OS was 4 months (17 months in responders) and 27% at 2 years. The median WT-1 transcript level in diagnostic AML samples was 5122 (range 9–36125), while in normal control samples it was 3 (n=11, mean 3.6, SD 1.6).
In multivariate Cox regression, stratified by cytogenetic risk group, age (p<0.001), LDH (p<0.001) and performance status (p=0.04) retained prognostic significance for OS and EFS. Elevated peripheral blood WT1 levels were significantly associated with impaired OS (HR 1.24 per log10 transcript levels p=0.022) and EFS (HR 1.31 per log10 transcript levels p=0.0019). WT1 levels correlated with cytogenetic risk group (p=0.002 with higher levels seen in the favourable risk group), antecedent haematological disorder (p=0.05), peripheral blood blast percentage (p=0.05) and bone marrow blast percentage (p=0.01). WT1 levels were significantly higher in acute promyelocytic leukaemia (p=0.0001) compared to other AML subtypes. WT1 levels did not correlate with age (p=0.16), sex (p=0.12), prior chemo/radiotherapy (p=0.96), performance status (p=0.33) or LDH (p=0.91).
Conclusions: WT1 RQ-PCR levels are frequently elevated in peripheral blood from patients with AML at diagnosis and are associated with subtype, cytogenetic risk group, blast percentage and antecedent haematological disorder. Within specified cytogenetic risk groups, elevated WT1 levels may predict AML patients at high risk of relapse and subsequent mortality.
Presence of Unbalanced Chromosomal Translocations Independently Predicts for Treatment Failure, Short Treatment-Free (TFS) and Overall Survival (OS) in B-Cell Chronic Lymphocytic Leukemia (B-CLL) Patients Treated with Cladribine.
Authors: Van Den Neste Eric W. , Robin Valérie , Francart Julie , Hagemeijer Anne , Stul Michel , Delannoy Andre , Sonet Anne , Costantini Sabrina , Ferrant Augustin , Deneys Véronique , Robert Annie , Michaux Lucienne 
Published: October 2019

Abstract
Chromosomal translocations have recently emerged as an important prognostic indicator in B-CLL (Mayr et al, Blood 2006). Until now however, their value had neither been determined in patients undergoing homogeneous treatment, nor compared to that of IgVH mutational status, another major prognostic factor in B-CLL. Sixty-five B-CLL pts treated with cladribine-containing regimens were included in the present analysis. All had been investigated by conventional cytogenetic analysis using TPA as a mitogen, interphase FISH (tested loci: 11q/ATM, 12cen, 17p/P53, 13q/RB1&/D13S319), IgVH mutational status and P53 mutational screening prior to inclusion. Translocations (n= 45) were detected in 42 % of the pts, and included both balanced (n=12) and unbalanced (n=33) types. Pts with translocations were more heavily pretreated (P=.05) and presented with significantly higher incidence of complex aberrations (P<.001), 17p aberrations (P<.001) and P53 gene mutations (P<.001). IgVH genes were mutated in 43% and unmutated in 57% of the pts. The presence of unbalanced translocations was associated with significant lower response rate (P=0.004), shorter median TFS (7 vs. 36 months, logrank 22.72, P<.004) and median OS (13 vs. 69 months, logrank 16.51, P<.001), as compared to patients without translocation. In multivariate analysis, translocations, especially the unbalanced subtypes, were significantly associated with the risk of therapeutic failure (P<.000, OR: 7.6) and short TFS (P<.000, HR: 2.12). In addition, the presence of unbalanced translocations proved to be the prognostic marker with the highest negative impact on OS (P=.013, HR: 4.4). Other prognostic factors independently associated with OS were abnormal cytogenetics, high LDH, prior treatment with alkylating agents, and age. IgVH mutational status was independently associated with risk of failure and TFS, but not OS. Interestingly, the presence of translocation(s) had strong negative impact on TFS and OS in IgVH mutated pts, whereas it did not modify outcome in unmutated ones. In conclusion, in B-CLL patients treated with cladribine, the presence of chromosomal translocations is a strong prognostic indicator. This indicates that conventional cytogenetics remains an important tool in defining individual B-CLL patient’s risk.
Simultaneous Analysis of Multiple Chromosomal Aberrations in Chronic Lymphocytic Leukemia (CLL) by Multiplex Ligation-Dependent Probe Amplification (MLPA).
Authors: Stevens-Kroef Marian J.P.L. , Simons Annet , Petersen Michael Egmont , Gorissen Hanneke , Nanciu Yvonne , Buijs Arjan , Raymakers Reinier , van Kessel Ad Geurts 
Published: October 2019

Abstract
B cell chronic lymphocytic leukemia (B-CLL) is characterized by a highly variable clinical course. Characteristic genomic abnormalities have shown to provide highly significant prognostic information (Dohner NEJM 2000). However, karyotyping and/or FISH are laborious and expensive techniques. Although other prognostic markers (like mutation status of VH-genes and expression of CD38 and ZAP70) have been noted, these fail to identify all patients with a cytogenetic high-risk profile. We have performed multiplex ligation-dependent probe amplification (MLPA) analysis on 37 CLL patients, using the P037 and P038 kits (mrc-holland, http://www.mlpa.com/pages/indexpag.html), which allow the simultaneous identification of 56 genomic CLL-specific targets. The MLPA data obtained were compared with interphase FISH data in a blinded fashion using the ATM, centromere 12, RB1, D13S319, and TP53 specific probes (Vysis). By doing so, a good correlation was revealed in those cases in which the percentage of abnormal cells was at least 27%. We diagnosed six cases with loss of the ATM locus, six cases with trisomy 12, twenty cases with loss of chromosome 13q14 (three of them with a biallelic deletion), and three cases with loss of the TP53 locus. In three cases the genetic abnormality was detected by interphase FISH only. In these latter cases, the percentages of abnormal cells were 13%, 20% and 20%, respectively, which may explain the false negative results of the MLPA analyses. Since multiple probes were used for the 13q14 loci, a critical region of genomic loss could be identified which excluded the RB1 gene but included the KCNRG, DLEU2 and DLEU1 genes and miRNA15A. Also for the TP53 and ATM genes multiple probes were tested and, based on these results, one patient is suspected to have an intragenic ATM deletion. Also, additional abnormalities were detected by MLPA as e.g. trisomy 19.
In conclusion, MLPA appears to be a useful technique for the identification of clinically relevant genetic abnormalities in a diagnostic setting.
A Novel, High-Throughput Assay for Detection of ABL T315I Mutations.
Authors: Heinrich Michael C. , Morich Jason R. , Beillard Emmanuel J. , Fuller Courtney , Galderisi Chad D. , Druker Brian J. 
Published: October 2019

Abstract
Mutations in the kinase domain of BCR-ABL result in impaired drug binding and are thought to be the leading cause of acquired resistance to the tyrosine kinase inhibitor imatinib (Gleevec®). While imatinib is a highly effective therapy in all stages of chronic myelogenous leukemia (CML), relapse after an initial response is common in patients with advanced disease. The T315I point mutation is one of the most common imatinib-resistant mutations and patients with this mutation are also resistant to two second generation tyrosine kinase inhibitors, dasatinib and nilotinib. Recently, the U.S. FDA approved dasatinib for treatment of imatinib-resistant, Philadelphia chromosome-positive acute and chronic leukemias. Thus, appropriate detection of this mutation is essential to optimal management of patients with imatinib resistance and may be useful for clinical trials of agents that target patients with the T315I mutation. Current methods for mutation detection, such as direct DNA sequencing, are not sensitive enough for detection of point mutations at low levels of BCR-ABL transcript. Conversely, ultrasensitive detection methods such as allele specific PCR (AS-PCR) may be too sensitive and can be plagued by false positive test results. In addition the clinical relevance/significance of mutation detection at ultra sensitive levels ( < 1% mutant) is questionable and not yet known. We developed a novel T315I mutation detection assay, using Fluorescent Resonance Energy Transfer (FRET)-based hybridization probes and melting curve analysis. BCR-ABL amplicons generated from a first round of PCR are amplified using primers flanking the ABL kinase region encoding for codon 315. The resultant amplicon is hybridized with fluorescein-labelled anchor probe and a LC Red 640-labelled T315I mutation specific probe. Wild-type and T315I mutant amplicons are distinguished by melting curve analysis (Roche Light Cycler 480™). Using a series of plasmid and cell line dilutions we determined that the sensitivity of this assay for detection of T315I mutations was 5–10%. Using patient-derived samples we were able to successfully genotype samples containing as few as 20–50 BCR-ABL transcripts. To date, the assay sensitivity and specificity are 100%. The assay is performed in a plate based format (96 or 384 wells) and commercially available software allows automated genotype assignment. This approach is suitable for high-throughput detection of T315I mutations for clinical management of CML patients and/or screening of patients to determine eligibility for clinical studies.
Clinical Analysis of Adult Acute Leukemia with Rearrangements of the 11q23/MLL: Multicenter Co-Operative Study.
Authors: Tamai Hayato , Yamaguchi Hiroki , Hamaguchi Hiroyuki , Yagasaki Humiharu , Bassyo Masami , Kobayashi Takeshi , Akiyama Hideki , Sakamaki Hisashi , Takahashi Satoshi , Tojo Arinobu , Ohmine Ken , Ozawa Keiya , Okumura Hirokazu , Nakao Shinji , Arai Ayako , Miura Osamu , Toyoda Shigeo , Gomi Seiji , Murai Yoshiro , Usui Noriko , Miyazawa Keisuke , Ohyashiki Kazuma , Takahashi Naoto , Sawada Kenichi , Kato Atsushi , Oshimi Kazuo , Inokuchi Koiti , Dan Kazuo 
Published: October 2019

Abstract
Background AL(acute leukemias) with 11q23 abnormalities involving the MLL (mixed lineage leukemia) gene comprise one category of recurring genetic abnormalities in the WHO classification. However, the prognosis of adult AL with 11q23/MLL between fusion partners are controversial especially in Asia.
Methods We analyzed data on 61 Japanese adult patients diagnosed as AL with 11q23/MLL abnormalities, including the translocations t(4;11), t(9;11), t(6;11), t(11;19) between 1990 and 2006.
Results Median age of the 61 patients was 48 years (range, 17–79 years). 54 patients were AML (acute myeloid leukemia) and 7 patients were ALL (acute lymphoblastic leukemia).The incidence by fusion partners in AML were as follows; t(9;11) in 29.6%, t(11;19) in 24.0%, t(6;11) in 18.5%. The incidence of patients with t(11;19) was higher than that in Caucasian and t(4;11) was lower than that in childhood. As for the FAB (French-American-British) subtype, 68.5% of the 11q23/MLL patients were M4/M5. Organ involvement was observed commonly (46.2%) in AML with 11q23/MLL patients except for t(11;19) (7.6%).The CR (complete remission) rate of AML with 11q23/MLL was not low (78.7%), but the CR duration was very short (10 months).The DFS (disease free survival) at 1year and the OS (overall survival) at 2 years were 20% and 30% in AML with t(9;11), 10% and 19% in AML with t(11;19), 10% and 30% in AML with t(6;11). In total, the DFS at 1year and the OS at 2 years were 26% and 25% in AML patients, respectively, while 50% and 50% in ALL patients, respectively. The DFS and the OS at 2 years were 44% and 53% in AML patients with 11q23/MLL who were treated with HSCT(hematopoietic stem cell transplantations), while 14% and 21% in those without HSCT respectively.
Conclusions Although there were reports that the prognosis of AML with t(9;11) was not bad in Caucasian, the present study showed poor prognosis of AML with 11q23/MLL in Japanese adult patients regardless of the fusion partners. Our study revealed the short CR duration of the AML patients with 11q23/MLL in the face of the high CR rate. AML patients with 11q23/MLL who were treated with HSCT had superior outcomes to those without HSCT (P=.04 for DFS and P=.04 for OS) .This findings suggest that treatment strategies including HSCT should be considered for AML with 11q23/MLL during the first CR.