bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Cell Polarity PTK7 Receptor Is Expressed in Myeloid Cells and Acts as a Modulator of the Chemotherapeutic Response in AML Patients.
Authors: Prebet Thomas , Lhoumeau Anne Catherine , Arnoulet Christine , Aulas Anais , Marchetto Sylvie , Sebbagh Michael , Esterni Benjamin , Vey Norbert , Borg Jean Paul 
Published: October 2019

Abstract
Abstract 1571
Poster Board I-596
The pseudo tyrosine kinase receptor 7 (PTK7) is an orphean tyrosine kinase receptor assigned to the planar cell polarity pathway (PCP). It has been recently described and plays a major role during embryogenesis and epithelial tissue organisation. To date there is no report in the litterature considering a potential implication in hematopoiesis. In silico and in vitro analysis found that PTK7 was also expressed in normal myeloid progenitors and CD34+ CD38- bone marrow cells in humans. Preliminary results from our team showed that PTK7 was also expressed in various leukemic cell lines such Jurkat, TF-1 or KG-1a. We decided to perform a wide range multicolour immunophenotyping screen on patients with acute myeloid leukemia (AML) at diagnosis and to investigate the role of PTK7 in AML in vitro. More than 250 patient samples were evaluated and we demonstrated that PTK7 was largely expressed in AML as 72% of the samples were PTK7 positive. Its expression mostly correlates with granulocytic lineage differentiation. PTK7 expression was associated with a lower WBC count at diagnosis and a lower frequency of extramedullary disease whatever was FAB subtype. Interestingly, PTK7 expression was associated with some cytogenetic subgroups including CBF-AML and APL. There was no correlation with molecular subgroups (i.e. FLT3-ITD/NPM1/CEBPA status). Overall Survival and Relapse Free Survival were evaluated in non-APL patients treated with induction chemo (n=182). Patients with PTK7 positive AML are more resistant to anthracycline-based frontline therapy with a significantly reduced Relapse Free Survival in a multivariate analysis model integrating all pre treatment variables (2 year probability of RFS= 29% vs 66% for PTK7 negative patients, p= 0.003). Forrest plot analysis showed that the negative impact of PTK7 expression was the most significant in intermediate cytogenetic risk subgroup and when PTK7 was aberrantly expressed in M4-M5 FAB subtypes. There was no demonstrated impact on CR. In cultured cells, expression of PTK7 promotes leukemia cell migration, cell survival and resistance to anthracyclin-induced apoptosis. There was no effect of PTK7 expression on cell proliferation in tritiated thymidine assay. In the absence of known inhibitor of PTK7, we produced a soluble recombinant PTK7-Fc protein that efficiently competes for PTK7 functions in cell migration and survival assays in cell lines and primary AML samples. These data were confirmed using a shRNA strategy. We conclude that PTK7 is a PCP component expressed in the myeloid progenitor compartment that conveys promigratory and anti-apoptotic signal to leukemia cells. Its use as a potential biomarker or therapeutical target should be investigated.

Disclosures
No relevant conflicts of interest to declare.
Expression Profiling of a Hemopoietic Cell Survival Transcriptome Identifies a Functional Prognostic Gene Signature in Normal Karyotype AML.
Authors: Guthridge Mark , Thomas Daniel , Barry Emma F , Chung Kok H , McClure Barbara J , To L. Bik , Goodall Greg , Speed Terry P , Osato Motomi , Haylock David , Nilsson Susie , D'Andrea Richard , Lopez Angel , Powell Jason A 
Published: October 2019

Abstract
Abstract 1618
Poster Board I-644
Deregulated cell survival programs are a classical hallmark of cancer. We have previously identified a serine residue (Ser585) in the cytoplasmic domain of the bc subunit of the granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 3 (IL-3) receptors that selectively and independently promotes hemopoietic cell survival. We now show that Ser585 phosphorylation is constitutive in the majority of acute myeloid leukemia (AML) patient samples indicating that this hemopoietic “survival-only” pathway is frequently deregulated in leukemia. This constitutive Ser585 phosphorylation is refractory to tyrosine kinase inhibitors allowing the survival of a quiescent population of leukemic progenitor cells in vitro. We performed a global expression screen to identify gene targets of this survival-only pathway and report a unique bc Ser585-regulated transcriptome. Pathway analysis defines a gene network enriched for PI 3-kinase target genes as well as a cluster of genes involved in cancer and cell survival. From this panel of Ser585-regulated genes, we have validated by Q-RT-PCR a “six-gene Ser585-signature” that is deregulated in AML blasts exhibiting constitutive Ser585 phosphorylation. We show that siRNA-mediated knockdown of key components of this Ser585-signature induces apoptosis in CD34+CD38-CD123+ leukemic stem and progenitor cells. Furthermore, multivariate analysis indicates that the Ser585-signature is an independent prognostic indicator of overall patient survival in normal karyotype AML (n=56, HR=2.0, p=0.01). These results delineate a novel cytokine-regulated Ser585/PI3-kinase signalling network that is deregulated in AML and identify new prognostic targets with therapeutic potential.

Disclosures
No relevant conflicts of interest to declare.
Final Results of a Phase 2 NCI Multicenter Study of Romidepsin in Patients with Relapsed Peripheral T-Cell Lymphoma (PTCL).
Authors: Piekarz Richard , Wright John , Frye Robin , Allen Steven L , Joske David , Kirschbaum Mark , Lewis Ian D. , Prince Miles , Smith Sonali , Jaffe Elaine S , Bates Susan 
Published: October 2019

Abstract
Abstract 1657
Poster Board I-683

Background
The histone deacetylase (HDAC) inhibitors are a class of epigenetic agents undergoing clinical testing. HDAC inhibitors modulate expression of genes involved in cell cycle regulation, leading to induction of differentiation or apoptosis. Romidepsin, a novel pan-HDAC inhibitor, has previously demonstrated activity as a single agent in patients (pts) with cutaneous T-cell lymphoma (CTCL) in two phase 2 studies.

Aims
To evaluate the efficacy and tolerability of romidepsin in the treatment of advanced PTCL and as an exploratory endpoint, to examine the molecular effects of romidepsin in both PTCL and CTCL.

Methods
This Phase 2, open-label, multi-arm, multicenter study enrolled 46 PTCL pts from the NCI and 9 extramural sites. CTCL pts were also enrolled in this study. This study is now closed to accrual. Pts with relapsed or refractory PTCL who had received at least one prior standard chemotherapy regimen were eligible. Pts received romidepsin 14 mg/m2 as a 4-hr infusion on days 1, 8 and 15 every 28 days. Responses were assessed using elements of the IWG criteria and RECIST, as appropriate, for pts with lymph node involvement and extranodal disease.

Results
46 pts (24 [52%] men and 22 [48%] women) with a mean age of 59 (range: 28 to 84) years were treated with romidepsin. 32 pts received ≥ 2 cycles of therapy. Mean number of prior therapies was 4.8 (range 1 to 14). Objective disease response rates (ORR) are summarized in the table. The mean number of cycles of treatment was 6.8 (range 1-47) and the overall median duration of response was 9.0 months (range 1.8 months to 5.8 yrs) for all pts. The median duration of response for the 5 pts who achieved CR was 6.0 months (range 2.8 months to 5.8 yrs).The most frequent drug-related AEs (all grades, all cycles) were generally mild and included: nausea (74%; 9% ≥grade 3), fatigue (72%; 20% ≥grade 3), decreased platelets (72%; 35% ≥grade 3), cardiovascular/general-other (72%; 0% ≥grade 3) and decreased AGC (65%; 43% ≥grade 3). One death, in a pt with significant cardiovascular disease who had achieved a CR, was considered possibly related to treatment.
Conclusions
This study demonstrates tolerability and durable clinical benefit (ORR of 33% and median duration of response of 9.0 months) of romidepsin in pts with recurrent or refractory PTCL. Based on these promising results, a Phase 2B protocol investigating romidepsin in pts with relapsed or refractory PTCL is ongoing at multiple international centers.

Disclosures
Kirschbaum: Gloucester Pharmaceuticals: Consultancy.
Efficacy of Abbreviated Stanford V Chemotherapy and Involved Field Radiotherapy in Early Stage Hodgkin's Disease: Mature Results of the G4 Trial.
Authors: Advani Ranjana H , Hoppe Richard T , Baer David M. , Mason Joseph , Rosenberg Saul A , Horning Sandra J 
Published: October 2019

Abstract
Abstract 1670
Poster Board I-696
The standard management for early stage Hodgkin's disease (HD) is combined modality therapy. In the G4 protocol, patients (pts) with non-bulky, supra-diaphragmatic stage I-IIA disease received 8 weeks of Stanford V chemotherapy + 30 Gy involved field radiotherapy (IFRT).
87 pts were enrolled and treated between 4/1996 and 4/2001. Median age was 30 years (16-59) and stages were IA (n=23), IIA (n=64). Unfavorable risk factors were present in 47 patients (54%) according to German Hodgkin Study Group (GHSG) criteria (> 2 AA sites, ESR > 50 or EN involvement) and 38 (44%) according to EORTC criteria (> 3 AA sites, ESR > 50). Therapy was well tolerated with grade 3-4 non-hematologic toxic events in 7 % of pts. These included constipation (n=3), peripheral neuropathy (n=1), generalized weakness (n=2), chest pain (n=1), mylagias (n=1), abdominal pain (n=1) and an allergic reaction to etoposide (n=1). 42 patients received cytokine support for grade 3-4 neutropenia however only 2 pts developed fever with neutropenia. No cases of clinical bleomycin toxicity or radiation pneumonitis were observed. At a median follow-up of 9 (2-12) years, freedom from progression (FFP) and survival (OS) are 94% and 96% respectively. FFP was 100% for favorable and 89% for unfavorable patients by GHSG criteria (p=0.04) with no differences in OS (96.9% versus 95.7%). All relapses (n=5) occurred in the RT field: limited in 2 patients and combined with distant disease in 3 pts. All relapses were in “unfavorable” risk patients: 5 per GHSG and 4 per EORTC criteria. Secondary therapy included chemotherapy followed by high dose therapy and stem cell support (n=3) and ABVD (n=2). Three pts died, 2 due to disease progression after second-line therapy and one due to metastatic colon cancer. 5 patients developed a second cancer (2 breast, 2 melanomas at unirradiated sites and 1 colon cancer). The cases of breast cancer were considered unrelated to RT as both occurred within 5-years of therapy in women who were > 30 yrs at time of treatment. No secondary AML and no late cardiac or pulmonary toxicities have been observed.
In conclusion, for pts with non-bulky stage I/II A HD, abbreviated Stanford V with 8 weeks of chemotherapy and 30 Gy IFRT is a safe and highly effective regimen. It is still too early to assess potential RT-related complications. Our outcomes in “unfavorable” stage I-IIA patients without bulky or symptomatic disease compare favorably with more intensive or prolonged regimens employed by the GHSG and EORTC.

Disclosures
No relevant conflicts of interest to declare.
A Recombinant Human Antibody to EphA3 with Pro-Apoptotic and Enhanced ADCC Activity Shows Selective Cytotoxicity against Myeloid Leukemia Cells and CD123-Positive Leukemic Stem Cells.
Authors: Palath Varghese , Vekhande Rohini , Lee Andreia , Williams Jason , Zhang Ling , List Alan F , Boyd Andrew , Lackmann Martin , Scott Andrew M , Cilloni Daniela , Yarranton Geoffrey T. , Bebbington Christopher 
Published: October 2019

Abstract
Abstract 1728
Poster Board I-754
Members of the Eph family of receptor tyrosine kinases play important roles in embryonic development but have restricted tissue distribution and activity in adult tissues. The EphA3 receptor is an oncofetal antigen expressed at high levels on the surface of several solid tumor types and certain leukemias. KaloBios is in pre-clinical development with KB004, a high-affinity recombinant human antibody, derived from a monoclonal anti-EphA3 antibody by Antibody HumaneeringTM Technology. KB004 binds EphA3 and stimulates apoptosis in primary cells from myeloid leukemia patients. The cell-surface expression of EphA3 was analyzed by flow cytometry on primary cells from chronic myeloid leukemia (CML) [n=10], acute myeloid leukemia (AML) of various sub-types [n=29], and myelodysplastic syndromes (MDS) [n=7]. EphA3 surface expression was detected in at least 50% of patient samples from each of the diseases analyzed. CD123-positive leukemia stem cells (CD34+ CD38- CD123+) also displayed surface expression of EphA3 whereas normal bone marrow CD34+ stem/ progenitor cells lacked detectable EphA3. KB004 was shown to stimulate apoptosis in EphA3+ primary leukemia cells, including CD123+ leukemic stem cells with no activity in EphA3-negative specimens, including normal CD34+ bone marrow cells. Cross-linking of the antibody was not required for induction of apoptosis. KB004 also inhibited myeloid leukemia colony formation (CFU-L) from primary AML samples in methylcellulose colony assays without affecting normal hematopoietic colony formation. In addition to its direct pro-apoptotic effect, KB004 induced potent antibody-dependent cellular cytotoxicity (ADCC) activity against EphA3-positive cells, mediated by CD16-expressing effector cells. CD16-dependent ADCC activity was further enhanced by expression of the antibody in CHO cells that lack a1,6 fucosyl transferase, generating afucosylated antibody with higher affinity for CD16a. The data support the development of an anti-EphA3 antibody for the treatment of hematologic malignancies in addition to solid tumors. In particular, the selective activity against leukemic stem cells supports a novel strategy for therapeutic targeting of leukemia-initiating cells that merits clinical investigation.

Disclosures
No relevant conflicts of interest to declare.
Conventional and Molecular Cytogenetic Responses in Patients with Myelodysplastic Syndrome (MDS) with Deletion 5q Treated with Lenalidomide.
Authors: Coutinho Rita , Costa Dolors , Carrió Ana , Vidal Ana , Belkaid Mohammed , Campo Elias , Montserrat Emili , Nomdedeu Benet 
Published: October 2019

Abstract
Abstract 1746
Poster Board I-772

Background and objectives
Interstitial deletions of the long arm of chromosome 5 - del (5q) - are the most common chromosomal abnormalities in MDS. Del (5q) is detected in 14 % of the patients. Lenalidomide induces complete cytogenetic remissions and abolishes transfusion dependence in a significant proportion of these patients, apparently correlated with the malignant clone suppression. The objectives of this study were to assess clinical and cytogenetic responses to Lenalidomide and to establish the relationship between the number of 5q deleted cells detected by conventional cytogenetics (CG) and by fluorescence in situ hybridization (FISH) previously and after treatment. Due to its larger sensitivity, the FISH technique might be able to predict an eventual loss of response to treatment.

Patients and methods
Bone marrow samples were collected at diagnosis and every 6 months from the beginning of treatment with lenalidomide. CG and FISH (with LSI EGR1 (5q31)SO/D5S23, D5S721 (5p15.2) probe, from Vysis) studies were performed in all samples, even in the cases that a complete cytogenetic remission was confirmed by karyotype during the treatment follow-up.

Results
We have treated 9 transfusion dependent MDS patients with lenalidomide, with a median age of 76 years (45-92). Four of the patients had one additional cytogenetic anomaly besides 5q deletion. Due to high clinical and cytological suspicion, one of the patients had a trisomy 9 by karyotype (2/20 metaphase) and was diagnosed of del (5q) by FISH, with a low clonal load (9,4% of deleted nuclei). Six patients were low IPSS risk, while 2 were Int-1 and one was Int-2 risk IPSS. All patients achieved complete erythroid response and transfusion independence (in a median of 8 weeks of treatment) and are still in response. Treatment was stopped in two patients after achieving complete hematologic response, maintaining normal hemoglobine levels for > 24 months. Five patients achieved cytogenetic remission, but 2 of them relapsed in a latter phase of the treatment (25 and 30 months). FISH analysis could not predict cytogenetic relapse in these two cases.

Conclusions
Our results support the established high efficacy of lenalidomide in MDS with del (5q). In our experience a single additional cytogenetic anomaly did not compromise hematologic response. Moreover, in our study FISH analysis did not bring additional information to CG analysis in prediction of response and follow-up in the majority of the cases.

Disclosures
No relevant conflicts of interest to declare.
Ribosomal Protein Genes S10 and S26 Are Commonly Mutated in Diamond-Blackfan Anemia.
Authors: Gazda Hanna T. , Sheen Mee Rie , Doherty Leana , Vlachos Adrianna , Choesmel Valerie , O'Donohue Marie-Francoise , Schneider Hal E. , Clinton Catherine , Sieff Colin A. , Newburger Peter E. , Ball Sarah E. , Niewiadomska Edyta , Matysiak Michal , Glader Bertil , Atsidaftos Eva , Lipton Jeffrey M. , Gleizes Pierre-Emmanuel , Beggs Alan H. 
Published: October 2019

Abstract
Abstract 175
Diamond-Blackfan anemia (DBA) is a congenital bone marrow failure syndrome characterized by anemia usually presenting during infancy or in early childhood, birth defects, and increased risk of cancer. Although anemia is the most prominent feature of DBA, the disease is also characterized by growth retardation and congenital malformations, in particular craniofacial, upper limb, heart and urinary system defects, that are present in ∼30–50% of patients. To date, DBA has been associated with mutations in seven ribosomal protein (RP) genes, S19, S24, S17, L35A, L5, L11, and S7 in about ∼43% of patients. To complete our large scale screen of RP genes in a DBA population, we sequenced 49 ribosomal protein genes in our DBA patient cohort of 117 probands. Together with our previous efforts of screening 29 RP genes, this completes the analysis of all known RP genes (excluding RPS4Y on the Y chromosome).
Here we report probable mutations in four more RP genes, RPS10, RPS26, RPL19, and RPL26, and variants of unknown significance in six more, RPL9, RPL14, RPL23A, RPL7, RPL35, and RPL3. RPS10 and RPS26 are now confirmed DBA genes as we identified five mutations in RPS10 in five probands and nine mutations in RPS26 in 12 probands. We found single small frameshifting deletions in RPL19 and RPL26 in single DBA families. Pre-rRNA analysis in lymphoblastoid cells from patients bearing mutations in RPS10 and RPS26 showed elevated levels of 18S-E pre-rRNA. This accumulation is consistent with the phenotype observed in HeLa cells after knock-down of RPS10 or RPS26 expression with siRNAs, which indicate that mutations in the RPS10 and RPS26 genes in DBA patients affect the function of the proteins. This brings to 11, the total number of RP genes mutated in ∼54% of patients with DBA, with nine more genes harboring variants of unknown significance requiring further study.

Disclosures:
No relevant conflicts of interest to declare.
Secretome Analyses of Primary Bone Marrow Fibroblasts Isolated From MGUS and Multiple Myeloma Show a Stepwise Occurrence of Alterations.
Authors: Drach Johannes , Slany Astrid , Mohr Thomas , Griss Johannes , Zielinski Christoph C , Gerner Christopher 
Published: October 2019

Abstract
Abstract 1801
Poster Board I-827
The microenvironment of tumor cells in the bone marrow was demonstrated to contribute to tumor promotion and survival. The role of bone marrow fibroblasts (BMFs) in supporting the malignant plasma cell clone in multiple myeloma (MM) has been established, but it remains unclear to which extent the BM microenvironment in general and BMFs in particular are involved in the progression of monoclonal gammopathy of undetermined significance (MGUS) to MM. Therefore we performed proteomics studies on the secretome of BMFs isolated from healthy donors, patients suffering from MGUS and patients suffering from MM. Compared to normal background, BMFs derived from MGUS secreted elevated levels of proteins indicating mitogenic activity and moderate inflammation. These proteins included periostin, IL-6, CXCL5 and CSF-1. Insulin-like growth factor II, which is normally not expressed by normal BMFs, was secreted by BMF cells derived from MGUS as well as from MM. In addition to those and other proteins, BMF cells derived from MM were found to specifically secrete stem cell growth factor, MMP-28 and stanniocalcin-1. These data indicate a step-wise alteration of BMF secretion activity related to the stage of the underlying plasma cell dyscrasia. Therefore BMF might support the progression from MGUS to MM. In order to correlate the secretion performance of BMF with blood serum levels of candidate marker proteins, Luminex assays are employed. Based upon these results, it is our aim to identify serum biomarkers which allow to assess the functional state of BMF and thus the risk for the progression of MGUS to MM.

Disclosures
No relevant conflicts of interest to declare.
Clonal Expansions of Cytotoxic T Cells in the Blood of Patients with Waldenstrom's Macroglobulinaemia Are Anergic and Disappear After Nucleoside Analogue Therapy.
Authors: Brown Ross D , Li Jia , Sze Daniel , Cowley Mark , Kaplan Warren , Yang Shihong , Aklilu Esther , Kabani Karieshma , Ho Phoebe Joy , Loh Yen S , Yamagishi Tetsuo , Mo Suilin , Chen Yuling , Joshua Douglas 
Published: October 2019

Abstract
Abstract 1820
Poster Board I-846
T cells contribute to the immunomodulatory control of the tumor in patients with monoclonal gammopathies. We previously found that CD3+CD8+CD57+TCRVβ+restricted cytotoxic T cell expansions were present in 48% of patients with multiple myeloma (n=221) and conferred a significant favorable prognosis. We now report the presence of these expansions in 70% of patients with Waldenstrom's Macroglobulinaemia (WM) (n=20) with a wide spectrum of the TCRVβ repertoire represented. Previous nucleoside analogue (NA) therapy, known to be associated with an increased incidence of transformation to aggressive lymphoma, significantly influenced the presence of TCRVβ expansions (χ2=11.6; p<0.001) as 5 of the 6 patients without and only 1 of the 14 patients with TCRVβ expansions had received NA. Clonality of CD3+CD8+CD57+TCRVβ-restricted cytotoxic T cells was confirmed by determining the size of the TCRVβ chain CDR3 region and by direct sequencing. We identified differential gene expression by using microarray analysis (Affymetrix GeneChip Human Genome U133 plus 2.0 Arrays) and confirmed the expression of selected genes by real-time qPCR and flow cytometry. Data was analysed by paired moderated t-test and then Gene Set Enrichment Analysis (GSEA) for pathway analysis. Clonal T cells not only had upregulated genes from cytotoxic pathways (granzyme B, perforin and FGFBP2) but also genes which suppress apoptosis, proliferation, cell cycle G1/S transition arrest and T cell activation (RAS, CSK and TOB pathways) indicating anergy which was validated by CFSE tracking of proliferation after antiCD3+antiCD28 stimulation. The current studies provide further evidence for the persistence and relevance of clonal T cells in monoclonal gammopathies.

Disclosures
No relevant conflicts of interest to declare.