bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased Sperm Count Maintains High Population Frequency of Factor V Leiden.
Authors: Cohn Danny M , Repping Sjoerd , Büller Harry R , Meijers Joost CM , Middeldorp Saskia
Published: October 2019

Abstract 3994

Poster Board III-930

Introduction

Factor V Leiden (FVL) increases the risk of venous thrombosis and pregnancy loss in carriers. Nevertheless, this relatively old mutation is still prevalent in Caucasion populations, which could be explained by positive selection pressure. Men with FVL have previously been found to have higher fecundity (the time between marriage and first pregnancy). Whether this is caused by increased fertility is unknown. We therefore aimed to assess whether men with FVL have increased fertility.

Patients and methods

We performed a pilot study in 19 men with FVL. For confirmation, we performed a cohort study among 961 consecutively included male partners of couples presenting at our university hospital for fertility workup between January 2000 and July 2007. We genotyped all participants and compared the outcome of the fertility workup between FVL carriers and non-carriers.

Results

The pilot study showed increased sperm concentration and total sperm counts in the 19 FVL carriers as compared to men from the general population. In the cohort study, we identified 37 FVL carriers and 921 non-carriers. FVL carriers had higher total sperm counts and total motile sperm counts than non-carriers: 236 ×106 (95% CI 158-292 ×106) versus 163 ×106 (95% CI 147-178 ×106) and 81 ×106 (95% CI 54-105 ×106) versus 52 ×106 (95% CI 48-57 ×106), respectively.

Conclusions

Our results provide a possible explanation for the high prevalence of FVL among Caucasians. To our knowledge, this is the first study that indicates that an increased prevalence of a genotype is controlled by increased sperm counts.

Disclosures:

No relevant conflicts of interest to declare.
A Chemical Genetic Analysis of Platelet Activation.
Authors: Flaumenhaft Robert , VerPlank Lynn , Dilks James R. , Blair Price S. , Mairuhu Albert , Negri Joseph , Burbank Jason , Walzer Gil , Aldredge Tyler , Dockendorff Chris , Gould Robert , MacPherson Lawrence , Palmer Michelle
Published: October 2019

Abstract 4009

Poster Board III-945

Platelets are anucleate cells that are not amenable to traditional forward genetic analysis. In collaboration with the Broad Institute Probe Development Center, we have performed a chemical genetic analysis of platelet activation. Chemical genetics involves exposure of cells to a library of small molecules, identification of compounds that produce a phenotype of interest, and determination of the target of these small molecules. We have used an assay designed both to identify allosteric inhibitors of Protease Activated Receptor-1 (PAR1) and to find inhibitors that selectively target granule release. This assay monitors dense granule secretion mediated by SFLLRN, a PAR1-specific agonist, using a luciferase-based assay system to detect ADP/ATP release. For primary screening, over 300,000 compounds were assayed in duplicate using freshly outdated platelet-rich plasma supplied by several blood banks across the United States. Computational analyses of the primary data demonstrated that approximately 0.2% of compounds showed ≥50% inhibition relative to maximally inhibitory concentrations of the known antiplatelet agent, cilostazol. Secondary screening using 8-point dose response curves were performed on the 629 inhibitory compounds, 742 compounds with inconclusive activity (e.g., ambiguous duplicates in primary screening), and 213 structural analogs of active compounds. These assays identified 367 active compounds with IC50s ≤10 micromolar. Counter screening to exclude luciferase inhibitors demonstrated 137 small molecules that inhibited PAR1-mediated ATP/ADP release without significant inhibition of luciferase. Database mining using PubChem and CAS search engines was performed to assess the selectivity of active compounds. Twenty eight compounds were selected for further testing based on their IC50s in confirmatory assays, lack of activity in unrelated bioassays, and chemical structure. Known platelet inhibitors were excluded. Of the 28 compounds, 16 compounds potently inhibited SFLLRN-induced alpha-granule release from washed platelets, as monitored by P-selectin expression. IC50s for these compounds ranged from <0.3 to 1 micromolar. None of the selected compounds that failed to inhibit alpha-granule release demonstrated significant inhibition of SFLLRN-induced 14C-serotonin release at 10 micromolar. Ongoing studies are directed at selecting best candidates from among the 16 confirmed inhibitory compounds to develop as biological probes that target either PAR1 activation or distal steps in granule secretion.

Disclosures:

No relevant conflicts of interest to declare.
A Novel Platelet Small-Molecule Agonist Targeting Glycoprotein Ibalpha.
Authors: Yang Jianfeng , Chen Zhi , Zhu Weiliang , Ruan Changgeng
Published: October 2019

Abstract 4010

Poster Board III-946

Introduction

Interaction of glycoprotein (GP) Ibα with Von Willebrand factor (VWF) plays a critical role in platelet adhesion and signal transduction for αIIbβ3 activation under condition of high shear stress.

Methods

Based on the crystal structure of platelet GPIbα (PDB:1P9A), virtual screening was employed to identify active compounds. Compounds in SPECS database were docked to VWF binding site on the surface of GPIbα. The screening was carried out with the DOCK4.0 program. The 150 highest-scoring compounds were obtained for further bioassay and those with inhibitory activity of VWF binding to GPIbα were investigated the effect on platelet activation and aggregation.

Results

We found one compound, designated it as YC148, blocked ristocetin-induced plasma VWF binding to recombinant N-terminal fragment GPIbα (H1-V289) by ELISA method. More interestingly, YC148 did not inhibit ristocetin-induced platelet aggregation, on the contrary, it induced platelet aggregation itself in the absence of exogenous modulators such as ristocetin and botrocetin. A VWF A1 blocking antibody could not block platelet aggregation induced by YC148 despite it completely inhibited ristocetin-induced platelet agglutination. And YC148 also stimulated washed platelet aggregation where VWF was absent in the resuspension buffer. These indicated that the aggregation stimulated by YC148 could not the result from VWF binding. Flow cytomety also showed that YC148 increased P-selectin expression on platelet membrane and promoted monoclonal antibody PAC-1 binding to platelet. The platelet aggregation stimulated by YC148 was inhibited by anti-GPIbα monoclonal antibody AN51 and 6D1.

Conclusion

A novel exogenous small-molecule agonist was found to activate platelet through binding to GPIbα. It provides us a new tool for investigating platelet GPIb outside-in signaling pathway in platelet adhesion and aggregation. Furthermore, the structure of YC148 may provide a structural basis for developing new hemostatic drugs based on the inhibition of VWF-GPIb interaction. The effect of YC148 on platelet from Bernard-Soulier syndrome or GPIbα N-terminal fragment deficient platelet after in vitro cleavage will be further investigated.

Disclosures:

No relevant conflicts of interest to declare.
Antagonism of P2y12 Receptor Results in Severe Impairment of Serum Thromboxane Levels. Can We Manage Patients without Combination Therapy with Aspirin?
Authors: Bhavaraju Kamala , Georgakis Alexander , Jin Jianguo , Tomiyama Yoshiaki , Nurden Alan T. , Nurden Paquita , Kunapuli Satya P.
Published: October 2019

Abstract 4013

Poster Board III-949

Anti-platelet therapy is a widely accepted treatment regimen for the management of patients with cardiovascular risks. In clinics, many patients with cardiovascular diseases are managed on a combination therapy with Aspirin and Clopidogrel. Aspirin, being a COX-1 inhibitor blocks thromboxane generation and Clopidogrel metabolite antagonizes the P2Y12 receptor (ADP receptor). Thus these drugs block the two most important platelet positive feedback mediators and prevent amplification of platelet responses. The molecular mechanism of P2Y12 receptor antagonism on impairment of serum thromboxane is not understood to-date. Understanding this mechanism will clarify the molecular effects of P2Y12 antagonists when aspirin is clinically contraindicated in patients.

Hypothesis

We hypothesized that P2Y12 antagonism would lead to a decrease in serum thromboxane generation. We tested our hypothesis by employing both pharmacological and molecular genetic approaches.

Methods and Results

Serum thromboxane levels are a cogent marker for platelet hyperreactivity. It is produced when thrombin, which is generated during coagulation cascades, acts on PAR receptors on platelets. Serum was collected from non-anticoagulated blood after clot formation, following which serum thromboxane levels were measured with ELISA. The serum thromboxane levels in mice dosed with clopidogrel (n=4) (30 mg/kg body weight) were inhibited 88.04% compared to untreated mice. In human blood treated with the active metabolites of clopidogrel (R138727) or prasugrel (R361015) (n=3) were inhibited by 83.7% and 95.1%, respectively, compared to untreated human serum (100%). We also evaluated serum thromboxane levels in P2Y receptor null mice (n=4). Where as serum thromboxane levels in P2Y1 null mice were similar to those in wild type littermates, those in the P2Y12 null mice were inhibited by 78.9%. Furthermore serum thromboxane levels in P2Y12 deficient patients previously described in France and Japan were reduced to 25.3% and 11.7%, respectively, compared to normal volunteers (100%). We had one patient who was only on clopidogrel whose serum thromboxane levels were inhibited by 92.1%, compared to normal volunteers. In a pilot study, we recruited healthy volunteers (n=6), who were given clopidogrel for a week. Serum thromboxane levels were measured before and after the administration of clopidogrel. On an average, the serum thromboxane levels in these volunteers were inhibited by 72.3% after receiving clopidogrel.

Conclusions

In conclusion, P2Y12 receptor antagonism alone could lead to decrease in serum thromboxane levels. Hence in future novel P2Y12 antagonists alone might offer better protection without an additional need for aspirin.

Disclosures:

No relevant conflicts of interest to declare.
Factor XIII Associates with the Guanine Exchange Factors Cool-1 and Cool-2 in Human Platelets.
Authors: Morgan-Spencer Alex , Greenberg Daniel L.
Published: October 2019

Abstract 4015

Poster Board III-951

A major signaling pathway that regulates platelet shape change and reorganization of the cytoskeleton involves the Rho family of GTPases; CDC42, Rac1 and RhoA. These GTPases are converted from their inactive or GDP-loaded state to the active or GTP-loaded state by a class of enzymes called Guanine Exchange Factors (GEFs). GEFs are a family of multi-domain proteins that contain a GDP-GTP exchange domain (DH-PH) as well as other protein interacting domains that are regulated by the activation of receptors present on the platelet surface. We previously identified the presence of two homologous GEFs, Cool-1 and Cool-2, in human platelets. In nucleated cells, the activities and substrate specificities of the Cool GEFs are regulated by complex interactions with p21-activated kinases (PAK), Gb/g heterodimers, focal adhesion kinase, and the scaffolding proteins GIT-1 and GIT-2. The Cool GEFs are found at the sites of focal adhesions during spreading and migration in nucleated cells, however, little is known about the regulation or activity of Cool-1 or Cool-2 in platelets.

Co-immunoprecipitation experiments were performed with Cool-1 and Cool-2 antibodies using lysates from resting and thrombin stimulated human platelets. We analyzed the precipitated proteins by Mass Spectroscopy and found a number of structural and scaffold proteins bound to the Cool GEFs in the thrombin activated lysates. These cytoskeletal proteins include talin, multimerin, tubulin, filamin A, actin and fibrinogen. Interestingly, a large number of Factor XIII also co-immunoprecipitated with Cool-1 and Cool-2 in the thrombin activated platelet lysates. Western analysis of the co-immunoprecipated platelet proteins from thrombin, TRAP1 and TRAP4 demonstrated that the association of factor XIII with the Cool GEFs is calcium dependent. Inhibition of transglutaminase activity and presence of RGD peptide did not affect the association of Factor XIII with Cool-1 or Cool-2.

Factor XIII deficiency is commonly thought to result in bleeding due to the impaired crosslinking of fibrin. However, platelet factor XIII may also play an important role in cross linking platelet cytoskeleletal proteins such as actin and myosin. Consistent with that hypothesis is a recent report showing that platelet factor XIII deficiency results in decreased lamellapodia formation under static adhesive conditions. The association of Factor XIII with the Cool GEFs further supports investigating the potential for the transglutaminase to crosslink platelet cytoskeletal proteins.

Disclosures:

No relevant conflicts of interest to declare.
Silent Brain Abnormalities in Thalassemia Intermedia: A Combined MRI/PET Study.
Authors: Taher Ali , Musallam Khaled , Nasreddine Wassim , Beydoun Ahmad
Published: October 2019

Abstract 4077

Poster Board III-1012

Introduction

Patients with thalassemia intermedia (TI) have an increased risk of thrombosis compared with thalassemia major patients. Thromboembolic events are more frequently observed in older TI patients (>20 yrs) who are splenectomized and non-transfused. Brain involvement has not been widely studied; however, one study has documented silent strokes on brain MRI in 37% of patients, indicating that further investigation is warranted.

Patients and methods

This was a cross-sectional study on 30 TI patients >18 years of age, splenectomized, not receiving regular transfusion therapy, and receiving no antiplatelet or anticoagulant medication. Patients were initially screened to establish absence of neurological signs or symptoms and other stroke-related disease (diabetes, hypertension, carotid stenosis, cardiac disease or prothrombotic mutations). All patients underwent both MRI and 18F-FDG PET scan on the same day. The criterion for abnormality on PET was the decrease in neuronal function (glucose utilization). MRIs were performed using T1- and T2- weighted spin-echo techniques. Abnormality was defined as an area of abnormally increased signal intensity on the T2-weighted pulse sequences.

Results

The mean age was 31.9 yrs (range: 18–54 yrs) with a male to female ratio of 13:17. Among the group of 30 subjects, 18 (60%) had abnormal MRI findings, 19 (63.3%) had abnormal PET findings, and 26 (86.7%) had either an abnormal MRI or abnormal PET or both. Solitary findings were identified in 7 (26.9%) of patients while multiple lesions were observed in 19 (73.1%) of patients who had abnormality. Bilateral findings were documented in 14 (53.8%) of patients with abnormality. The most common regions of abnormality were the parietal (76.9%) and frontal (69.2%) lobes; followed by the temporal (53.8%) and occipital (15.4%) lobes.

Conclusions

MRI/PET evaluation has demonstrated that silent brain abnormality is a common finding in this population of adult, splenectomized, non-regularly-transfused TI patients.

Disclosures:

Taher: Novartis: Honoraria, Research Funding.
Phase I Trial of Nanomolecular Liposomal Annamycin in Adult Patients with Refractory Acute Lymphoblastic Leukemia.
Authors: Wetzler Meir , Wang Eunice S. , Shepard Robert , Thomas Deborah A. , Andreeff Michael , O'Brien Susan , Kantarjian Hagop M.
Published: October 2019

Abstract 4098

There continues to be no effective second line therapy for refractory acute lymphoblastic leukemia (ALL) in adult patients and the cure rate with current therapy has not significantly improved in decades. Annamycin is a highly lipophilic form of the anthracycline doxorubicin with the ability to bypass multi-drug resistance (MDR-1) mechanisms of cellular drug resistance. A novel nanomolecular liposomal entity of annamycin was recently specifically synthesized which overcomes MDR with little to no cardiac toxicity and improved anti-tumor activity when compared to the original annamycin formulation. We performed a phase I multi-center, open-label, study to determine the maximally tolerated dose (MTD) of nanomolecular liposomal annamycin in adult patients with refractory ALL. The secondary objective was to study the MDR-1 encoded (permeability glycoprotein) PgP-170 glycoprotein expression in correlation with CD34 expression and MDR-1 mRNA levels in refractory ALL patients prior to and after receiving liposomal annamycin treatment. Thirty patients were enrolled on the study. The MTD was determined to be 150 mg/m2/day for 3 days. Other than the tumor lysis syndrome, there was only 1 severe adverse event (SAE) definitely related to the study drug consisting of grade 3 mucositis. There were also 3 other SAEs of grade 3-4 mucositis probably related to the study drug which comprised the MTD determination. There was no reported cardiac toxicity in any patients. After determining the MTD, a 10-patient phase IIA was conducted. Eight of the patients completed 1 cycle of the 3 days of treatment at the MTD. Of these, 5 (62%) had an efficacy signal with complete clearing of circulating peripheral blasts. Three of these subjects also cleared bone marrow blasts with one subsequently proceeding onto successful stem cell transplantation. The other 2 developed tumor lysis syndrome and unfortunately expired prior to response assessment. Nanomolecular liposomal annamycin appears to be well-tolerated with no cardiotoxicity and evidence of clinical activity as a single agent in refractory adult ALL. Given that the likely mechanism of action is overcoming innate drug resistance via MDR, PgP-170 mRNA and protein expression will be presented. We are currently testing liposomal annamycin in a phase I study in children and young adults with refractory ALL or AML, and planning a phase 2 registration trial in adult ALL

Disclosures:

Wetzler: Callisto Reserach Funding: Research Funding. Off Label Use: Annamycin. Refractory relapse to ALL. Wang:Callisto : Research Funding. Shepard:Callisto: Research Funding. Thomas:Callisto: Research Funding. Andreeff:Callisto: Research Funding. Kantarjian:Callisto: Research Funding.
To Study the Proliferative Inhibition of Anticancer Drug in Two Kinds of Ph (+) Leukemia Cell Lines.
Authors: Gong Yuping , Yang Xi , Niu Ting
Published: October 2019

Abstract 4110

Objective

To study the proliferative inhibition of imatinib, daunorubicin and bortezomib in two kinds of Ph(+) leukemia cell lines: chronic myelogenous leukemia cell line K562 expressing P210 protein and acute lymphoblastic leukemia cell line SUP-B15 expressing P190 protein.

Methods

(1) Cell proliferation with imatinib, daunorubicin and bortezomib for 72 hours was analyzed by the MTT assay and displayed by growth curve and IC50 value. (2) The change of bcr-abl gene mRNA levels after the 48 hours' intervention of imatinib (final concentration at 0μM, 0.35μM, 1 μM) was detected by reverse transcription polymerase chain reaction (RT-PCR).

Results

(1) The IC50 values of K562 and SUP-B15 cells inhibited by imatinib, daunorubicin and bortezomib for 72 hours was respectively 0.286±0.06 (μmol/L), 0.303±0.009 (μmol/L), 22.127±3.592 (nmol/L) and 1.387±0.180(μmol/L), 0.117±0.017 (μmol/L), 12.350±0.740 (nmol/L), which indicated that the K562 cell line was the more sensitive to imatinib than SUP-B15 cell line, whereas the SUP-B15 cell line had the more sensitivity to daunorubicin and bortezomib. (2) There was no change of bcr-abl gene expression after the 48 hours' intervention of imatinib in both cell lines.

Conclusion

(1) Imatinib, daunorubicin and bortezomib had good anti-cancer effect to Ph+ leukemia cells in vitro. What's more, the K562 cell was the more sensitive to imatinib and only imatinib will have good effect on chronic myelogenous leukemia. Whereas the SUP-B15 cell had the more sensitivity to daunorubicin and bortezomib and combining imatinib with daunorubicin or bortezomib, the effect will be better on Ph(+) acute lymphoblastic leukemia. (2) The short time intervention of imatinib had no effect on the bcr-abl gene expression and imatinib could need long time to show curative effect for the Ph+ leukemia.

Disclosures:

No relevant conflicts of interest to declare.
Multiprobe FISH Panels for Chromosome Rearrangements in Patients with Adult Acute Lymphoblastic Leukemia.
Authors: Du Qingfeng , Xiaoli Liu , Xu Na , Liu Zhi , Li Rong , Song Lanlin , Cao Rui , Yang Jun , Wang Yu , Xu Lulu
Published: October 2019

Abstract 4122

For acute Lymphoblastic Leukemia(ALL), several cytogenetic aberrations have been shown to play a crucial role in clinical Prognosis and also are being used as targets for response to therapy. This has led to Cytogenetics, and more recently Fluorescence In Situ ybridization(FISH), to be a tool for the detection of ALL treatment trials. Conventional cytogenetic(CC) analysis is a technically demanding and time-consuming process that is hindered by the limited availability of informative metaphase cells. Thus, interphase FISH is often used to complement CC,rule out submicroscopic rearrangements, and evaluate specimens with poor morphology or no growth in culture.

The Chromoprobe Multiprobe ALL panel (Cytocell Technologies,Cambridge, UK) has been designed to detect rearrangements that occur primarily in B-cell lineage ALL, and includ some T-lineage markers. This panel detect the rearrangements of MYC, E2A, MLL, IGH, and p16; fusions of BCR/ABL and TEL/AML1 simultaneously; enumeration of chromosomes 4, 10, and 17 Probes for the specific rearrangements can also be used to assess ploidy. In this study, we performed the multi-probe FISH assay on interphase cells to detect multiple abnormalities associated with adult ALL.At prensent, We analyzed 48 samples from ALL cases using a FISH panel,the results showed that 71% cases had 1 or more genetic abnormalities. The most frequent abnormality was BCR/ABL, followed by MLL, IGH abnormalities, MYC rearrangement, TEL/AML1 fusion, +10, p16, 8 cases had MLL with IGH abnormalities and TEL/AML1 fusion, 7 cases had BCR/ABL fusion with MYC rearrangement,3cases had MLL and p16, no fusion partner was detected in 14 cases. Meanwhile,detected this samples with CC,we found that 42% cases had chromosome abnormalities,and 16% samples without growth in culture. This reults preliminary demonstrated that ALL always with multiple karyotype abnormalities, Multiprobe FISH is an essential method to refine the cytogenetic analysis. This study is going on,further study including more samples was necessary.

Disclosures:

No relevant conflicts of interest to declare.
CD19 Expression in t(8;21)-Negative Acute Myeloid Leukemia Is Not Restricted to Cytogenetically Aberrant Populations.
Authors: Francis Jawad , Dharmadhikari Avinash , Sait Sheila N.J. , Deeb George , Wallace Paul K. , Thompson James E. , Wang Eunice S. , Wetzler Meir
Published: October 2019

Abstract 4128

Aberrant expression of the B lymphoid marker, CD19, in acute myeloid leukemia (AML) has frequently been associated with t(8;21)(q22;q22). However, AML cases lacking this translocation may occasionally express CD19. We identified eight such cases at Roswell Park Cancer Institute. Three of these cases had noticeable CD19-positive leukemic subsets with the following karyotypic abnormalities. The first case had monosomy X in 6 cells and normal karyotype in 14, the second case had trisomy 22 in 19 cells and normal karyotype in one, and the third case had monosomy 7 in 18 cells and trisomy 18 in two. We therefore asked if CD19 expression is restricted to the karyotypically abnormal leukemic cells. Bone marrow cells were sorted according to the specific immunophenotype. First, a generous mononuclear sorting region was drawn in the bivariate display of forward versus side scatter to exclude debris and aggregates. Next, the CD45-negative to CD45-dim, CD19-positive and CD34-positive leukemic cells were sorted. Fluorescent in situ hybridization (FISH) studies were carried out on the sorted samples using the following commercially available probes: the Centromere enumeration probe CEP X (SpectrumGreen) in the first case; the locus specific BCR (22q11) (SpectrumGreen)/ABL1 (9q34) (SpectrumOrange) dual color, dual fusion, translocation probe in the second, and the locus specific D7S486 (7q31) SpectrumOrange/CEP 7 SpectrumGreen probe in the third. A total of 200 nuclei were assessed in each case. The results are displayed in the Table below. There were no significant differences in the signal pattern between the CD19-positive and CD19-negative leukemic populations. These results indicate that aberrant CD19 expression in t(8;21)-negative AML is not restricted to leukemic cells that harbor specific karyotypic abnormalities.

Table FISH results based on CD19 expression Case # Probe Signal Pattern CD19-positive CD19-negative 1 CEP X 1 Green (-X) 20/200 30/200 2 BCR/ABL 3 Green/2 Orange (+22) 163/200 170/200 3 CEP 7 1 Green/1 Orange (-7) 200/200 200/200

Disclosures:

No relevant conflicts of interest to declare.
Association Between Genetic Polymorphism in DNA Repair Genes and Acute Myeloid Leukemia.
Authors: Kim Hee Nam , Kim Nan young , Yu Li , Tran Huong Thi Thanh , Kim Yeo-Kyeoung , Lee Il-Kwon , Yang Deok-Hwan , Lee Je-Jung , Kim Hee-Je , Min Woo-Sung , Park Moo-Rim , Jo Deog Yeon , Won Jong Ho , Kwak Jae-Yong , Kim Hyeoung-Joon
Published: October 2019

Abstract 4131

Genetic variants in DNA repair genes may affect DNA repair capacity and modulate cancer susceptibility. We analyzed genetic polymorphisms of 11 DNA repair genes: XRCC4, BRCA1, WRN, RAD51, XRCC3, ERCC1, ERCC2, XPC, OGG1, XRCC1 and MGMT to evaluate the association and risk of acute myeloid leukemia (AML). A large-scale population-based, case-control study of 1700 controls and 659 cases was conducted in Chonnam National University Hwasun Hospital, Korea.

Three single-nucleotide polymorphisms(SNPs), ERCC1 IVS5 +33 CC, WRN 787 GG and XRCC1 399 GA genotypes were associated with decreased risk for AML [odds ratio (OR) = 0.71; 95% confidence interval (CI) = 0.54-0.92, p=0.01 for IVS5 +33 CC, 0.67; 0.50–0.89, p=0.006 for 3149 GG and 0.81; 0.67–0.98, p=0.031 for 1316 GA]. We found no differences in the XRCC4 S307, BRCA1 P87L, RAD51 –G135C, XRCC3 T241M, ERCC2 K751Q, XPC K939Q, OGG1 S326C and MGMT L84F genotypes.

Our results suggest that these 3 SNPs in DNA repair genes may affect AML susceptibility by modulating activities to maintain the genome integrity of each individual.

Disclosures:

No relevant conflicts of interest to declare.
Expression and Clinical Significance of Antiapoptotic Gene Aven in De Novo acute Myeloid Leukemia Patients.
Authors: Geng SuXia , Du Xin , Weng Jianyu , Zhong Liye , Guo Rong , Lu Zesheng , Wu Suijing
Published: October 2019

Abstract 4132

The objective was to definite the expression level of aven mRNA of white blood cells from peripheral blood(PB)of de novo acute myeloid leukemia and preliminary analyze its clinical significance, providing a experimental basis for evaluating prognosis. Aven mRNA levels in PB samples from 69 AML patients were detected by using real-time quantitative PCR. The relation of aven mRNA level with clinical and hematological characteristics (age, sex, WBC, Hb, Plt, LDH, Blast% in PB and BM,FAB subtype) and treatment outcome (complete remission rate and relapse rate)were analyzed. Twenty-one normal individuals served as controls. The level of aven mRNA was between 11.72% and 178.93 %(median 37.2%) in de novo AML and between 10.81% and 50.98 %(median 28.81%) in normal individuals. Aven mRNA level was higher in the AML group than in the controls (p=0.006). When we compared aven mRNA with other clinical and hematological parameters, there were significant correlations between aven mRNA and age(r=0.25,p=0.039),aven mRNA and hemoglobin level (r=0.29,p=0.019),aven mRNA and FAB subtype(r=0.253,p=0.036). We found that median level of aven mRNA in group whose age older than median age was higher than group whose age younger than median level(p=0.018).The complete remission rate after two cycles chemotherapy in group with lower aven mRNA level(25/30,83.33%)was higher than group with higher aven mRNA level(21/30,70%). But the difference was not significant(p=0.22).The difference of aven mRNA expression level between AML patients with relapse and that without relapse was not significant (p=0.076). In conclusions, the level of aven mRNA in de novo AML is overexpression. The overexpression of aven mRNA is likely to play an important role in tumorigenesis of AML. Association of aven mRNA expression with treatment outcome and relapse was not observed.

Disclosures:

No relevant conflicts of interest to declare.
Phase I Study of Bendamustine in Refractory Leukemia.
Authors: Beth Rios Mary , Jabbour Elias , Ravandi Farhad , Kadia Tapan , Estrov Zeev , Borthakur Gautam , Burton Elizabeth , Kantarjian Hagop M.
Published: October 2019

Abstract 4156

Background

Alkylating agents are active in leukemia. Examples are cyclophosphamide, chlorambucil, melphalan, busulfan, and others. Bendamustine, a rationally designed drug that incorporates alkylating agent properties plus an adenosine-like ring structure, may be active in leukemia. Fractionated doses of alkylators may improve efficacy (e.g. fractioned cyclophosphamide in ALL).

Methods

We initiated a phase I-II study of bendamustine in patients with refractory leukemia, chronic myelomonocytic leukemia, or myelodysplastic syndromes. Starting dose was 50mg/m2 IV BID over 1-2 hours for 4 days every 4 weeks (3 pts.) with escalation to 75mg (3 pts.), and 100mg (6 pts). Three additional patients were treated at 50mg/m2 once that dose was declared safe as allowed by study design. Diagnoses were AML 12, ALL 2, MDS 1. Median age was 48 (range 22 to 88). All patients were refractory or had relapsed after multiple courses of chemotherapy. The median number of prior therapies was 3 (range 1 to 9). Five patients had chromosome 5, 7, or 8 abnormalities, 6 patients had miscellaneous abnormalities, 4 patients were diploid.

Results

Toxicity – Grade 1-2 expected toxicities of nausea, vomiting, diarrhea, and transient transaminase elevations were seen at all dose levels. At the 75 mg/m2 dose level grade 3 transaminase elevation was seen in 1 pt. which occurred with rash and diarrhea, was thought to be related to GVHD and all subsided with dose increase of tacrolimus. One patient who began therapy with a creatinine of 1.8 had creatinine increase to 3.3 mg/DL. At the 100mg/m2 dose level 2/3 patients developed creatinine increase to 3.2 and 2.6 mg/DL. The creatinine increase occurred on day 7 and subsided by day 11 in both pts. An additional 3 pts. were treated at this dose level with no increase in creatinine to >2 mg/DL.

Results

Response – Antileukemic activity was encouraging: 8/15 patients with peripheral blasts had >90% reduction of the leukemic cells; 2 patients had >50% reduction of marrow blasts % (90 to 10, 86 to 40).

Bendamustine has shown activity in this heavily pretreated refractory leukemia group. While the creatinine elevations were not severe (grade 3-4 NCI CTC) they were consistent to consider a bendamustine dose schedule of 50-75 mg/m2 IV BID x 4 days as a reasonable phase II schedule to explore in better prognosis patients, particularly in adult ALL in phase II studies.

Disclosures:

Ravandi: Cephalon: Consultancy, Honoraria. Kantarjian:Cephalon: Research Funding.
Cytomegalovirus Infection in Patients with Acute Leukemia and MDS.
Authors: Yuasa Hiromi , Kyo Taiichi , Yoshida Noriaki , Katayama Yuta , Asaoku Hideki
Published: October 2019

Abstract 4167

[Background]

It is important for the progress of the support treatment for AML. It is possible for more than seventy years old patients to cure AML actively.

[Purpose]

We examined the CMV reactivation after chemotherapy of AML, MDS, and ALL.

[Methods]

The study design planned to enroll 195 patients. Diagnoses included AML (121), MDS (56), ALL (18). Patients received induction chemotherapy. Induction regimens consisted of IDA (12 mg/m2 per day, day 1, 3, 5 and 8) and BHAC (350 mg/ m2 per day, day 1-10)(= Ara-C 200 mg/ m2 per day, day 1-10). Patients received consolidation chemotherapy. Consolidation chemotherapy comprised of High-dose Ara-C Therapy-containing regimens. We examined the CMV reactivation when patients have fever but they were recovered from the leukocyte decrease term after chemotherapy.

[Results]

About 10% of patients experienced CMV reactivation. Thirteen of 121 AML patients experienced CMV reactivation. Three of 56 MDS patients experienced CMV reactivation. Four of 18 ALL patients experienced CMV reactivation.

[Conclusion]

It is important to be careful for CMV reactivation in patients receiving High-dose Ara-C Therapy.

Disclosures:

No relevant conflicts of interest to declare.
Pharmacodynamic Differences of An Anti-Xa Enriched Low Molecular Weight Heparin, AVE 5026 in Comparison to Enoxaparin and Unfractionated Heparin.
Authors: Hoppensteadt Debra , Gray Angel , Litinas Evangelos , Kaiser Brigitte , Fareed Jawed
Published: October 2019

Abstract 4171

AVE5026 (Sanofi-Aventis, Paris, France) represents an anti-Factor (F) Xa enriched ultra low molecular weight heparin (ULMWH) (Mw=2.4 Kda; anti-FXa activity ∼160 U/mg). In comparison to Enoxaparin it has a lower anti-FIIa activity (∼2 U/mg). The oligosaccharide composition of AVE5026 also differs from Enoxaparin and other LMWHs. Besides the molecular and compositional differences, the biologic half-life of AVE5026 (18-20 hours) is significantly longer than Enoxaparin (4-6 hours). In order to compare the other pharmacodynamic differences between AVE5026, Enoxaparin and unfractionated heparin (UFH), a primate model (macaca mulatto) was used since its tissue factor pathway inhibitor (TFPI) profile is comparable to the human response. Individual groups of primates (n=6) were administered with 1 mg/kg SC of either AVE5026, Enoxaparin or UFH. Heptest and APTT measurements were determined on whole blood (WB) and plasma was analyzed for APTT, Heptest, thrombin time (TT), anti-FXa and anti-FIIa effects at varying periods up to 28 hours. TFPI antigen was measured using the assay from Stago (Parsipanny, NJ). Functional TFPI measurements were determined using the kit from American Diagnostica (Stamford, CT). In contrast to UFH, in the WB assays, neither the AVE5026 nor the Enoxaparin produced a strong effect on the APTT and TT, however both demonstrated a strong effect on the heptest assay. AVE5026 produced a much stronger effect with a longer half-life (T½=11 hrs) in comparison to Enoxaparin (T½=6 hrs). In the plasma based systems only UFH produced a measurable effect on the APTT and TT. However, in the heptest and anti-FXa assays, both AVE5026 and Enoxaparin produced a stronger effect, which was much longer with AVE5026 (2-3 fold increase). The plasma time course of TFPI antigen release was longer with AVE5026 in comparison to Enoxaparin and UFH. The ratios of immunologic to functional TFPI levels were also higher in the primates administered with AVE 5026. In the thrombin generation test, AVE5026 produced a sustained effect which lasted longer than Enoxaparin (T½ =16.8 hrs vs. 9.2 hrs.). These results show that AVE5026 produces stronger anti-FXa effects in primates which are associated with a higher circulating level of TFPI and more pronounced suppression of thrombin generation compared to Enoxaparin and UFH.

Disclosures:

Hoppensteadt: Sanofi-Aventis: Research Funding.
Combination of FXI Antisense Oligonucleotide and Plavix® Treatment Results in Enhanced Antithrombotic Activity without Increased Risk of Bleeding in Mouse Models of Thrombosis.
Authors: Gao Dacao , Crosby Jeff , MacLeod Robert , Bhattacharjee Gourab , Lowenberg Ester C , Levi Marcel , Monia Brett P.
Published: October 2019

Abstract 4173

Factor XI (FXI) is a serine protease produced in the liver that contributes to thrombin generation via the intrinsic coagulation pathway. Also, it is a key component of an amplification pathway that is thought to sustain thrombin production at a wound site to maintain fibrin clot integrity. Loss of function mutations in the human FXI gene results in FXI deficiency, a disorder which is associated with only mild bleeding. In addition, high levels of FXI are a risk factor for thrombosis. We have previously presented the antithrombotic efficacy and safety of antisense oligonucleotide (ASO) mediated FXI depletion in various animal models of thrombosis. We have demonstrated that in combination with Lovenox®, FXI ASO treatment increases antithrombotic activity but does not increase bleeding risk. The purpose of the current study was to evaluate the relative risk/benefit of ASO mediated Factor XI depletion in combination with the platelet antagonist Plavix®. The “risk” component was bleeding tendency as measured by blood volume loss following tail nick, and the “benefit” component was antithrombotic effect in arterial and venous mouse models of thrombosis. Our study investigated a 20 mg/kg dose of FXI ASO in combination with a dose response of Plavix® and indicates that antisense mediated FXI depletion provides enhanced antithrombotic protection when given in combination with Plavix®. The combination of FXI ASO and Plavix® did not result in increased bleeding tendency. In contrast, treatment with a small molecule inhibitor of factor Xa in combination with Plavix® significantly increased bleeding. The approach used in this study is being used to define the ability of FXI ASO to combine with standard of care agents for the treatment of thrombosis.

Disclosures:

Gao: Isis Pharmaceuticals, Inc.: Employment. Crosby:Isis Pharmaceuticals, Inc.: Employment. MacLeod:Isis Pharmaceuticals: Employment. Bhattacharjee:Isis Pharmaceuticals, Inc.: Employment. Lowenberg:Isis Pharmaceuticals, Inc.: Consultancy. Levi:Isis Pharmaceuticals, Inc.: Consultancy. Monia:Isis Pharmaceuticals, Inc.: Employment.
Stability of the INR in Relation to Personality Traits in Patients On Stable Oral Anticoagulant Therapy.
Authors: Harenberg Job , Weiss Christel , Felten Marie-Theres , Frölich Lutz
Published: October 2019

Abstract 4178

Maintenance of a stable anticoagulation as determined by the international standardized ratio (INR) remains difficult despite increasing knowledge on genetic variations of metabolism and improved therapeutic approaches. We hypothesised that personality traits of patients may influence the stability of the INR, obtained during stable therapy with vitamin-K antagonist (VKA). We assumed that the standard deviation (SD) of the INR over a time period of 6 months represents the stability of the anticoagulant treatment.

Patients (n=28) treated with VKA for more than one year in our outpatient care unit, completed a widely used personality inventory (Freiburger Persönlichkeitsinventar, FPI-R) and a questionnaire referring to general health and quality of life (SF12). Correlations between factors of FPI-R and SF12 with the standard deviation (SD) of the INR were analysed by means of the spearman correlation coefficient.

76% of all INRs of the patients were within the therapeutic range of 2 to 4 and the SDs of the patients INRs ranged from 0.23 to 1.17. The higher the social competence (FPI-R) of a person the lower was the SD of the INRs (p=0.0003). The less calm and relaxed a person felt in the past (SF12), the lower was the SD of the INRs (p=0.013). No other personality dimensions or domains of the SF-12 correlated with the variance of the INRs.

A high social competence and low score of a person feeling calm and relaxed leads to a more stable anticoagulation of patients treated with VKAs. The first finding may relate to subjects with good cooperation and social responsibility resulting in a stable anticoagulant therapy. Patients who feel troubled and worried by higher variations of INR values may cause the second finding. The data suggest that personality traits play a role for reaching a stable INR.

Disclosures:

Harenberg: Bristol-Myers Squibb: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi Aventis: Consultancy, Honoraria; Roche Diagnostics: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Bayer Health Care: Consultancy, Honoraria.
Relation of Personality Traits in Patients with Oral Anticoagulant Therapy to Attitudes towards Treatment with Vitamin-K Antagonists.
Authors: Harenberg Job , Frölich Lutz , Felten Marie-Theres , Weiss Christel
Published: October 2019

Abstract 4183

Stable anticoagulation as determined by the international standardized ratio (INR) remains difficult despite increasing knowledge on pharmacogenetics of vitamin K antagonists (VKA) and improved therapeutic approaches. We hypothesised that personality traits of patients may influence attitudes towards treatment VKA.

Thirty patients treated with VKA for more than one year completed a widely used personality inventory (Freiburger Persönlichkeitsinventar, FPI-R) and a questionnaire referring to adherence, safety and anxiety problems during anticoagulant therapy after written informed consent. Indications for anticoagulation were venous thromboembolism (n=22) and atrial fibrillation (n=8). Correlations between FPI-R factors and items of the anticoagulant therapy questionnaire were analysed by means of the chi-square test.

Patients understanding the concept of VKA therapy and being open for modifications of the dose of VKA, they are more emotional and less excitable (p=0.008 and 0.009), respectively. Patients who felt burdened at initiation of VKA therapy were less achievement-oriented (p=0.02). Those who forget sometimes the intake of the VKA are more self-inhibited (p=0.004) and more socially oriented (p=0.007). Patients following a diet during anticoagulant therapy, are more concerned about general health (p=0.009) and are more socially orientated (p=0.05). Those who like to eat vitamin-K containing vegetables are more excitable (p=0.01). Importantly, patients being afraid of thrombotic events are more aggressive (p=0.01) and have more physical complaints (p=0.02). Those being afraid of bleeding complications, are more aggressive (p=0.046), more demanded (p=0.05) and more intraverted (p=0.004).

Personality traits appear to influence the therapy with VKA manifold. Fear of thrombotic or bleeding events during anticoagulant therapy can be identified by specific personality traits.

Disclosures:

Harenberg: Bristol-Myers Squibb: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi Aventis: Consultancy, Honoraria; Roche Diagnostics: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Bayer Health Care: Consultancy, Honoraria.
An Old Story: Aggressive Antithrombotic Approach Reduced or Increased the Risk of Destabilization and Adverse Events: More Questions Than Answers.
Authors: Corinaldesi Giorgio , Corinaldesi Christian
Published: October 2019

Abstract 4185

Aggressive antithrombotic therapy with ASA, thienopyridine, GPIIb/IIIa inhbitors, eparin, and Vit.K antagonist (VKA) is used for unstable angina (UA), myocardial infarction (NSTEMI), acute coronary syndrome (ACS), stent implantation, atrial fibrillation (AF),VTE. The main findings of combination of antithrombotic drugs are their association with serious bleeding not withstanding some respectable benefit, and a great effects against thrombosis. At present the preferred approach for the long term treatment is VKA the dose should be adjusted to maintain a target INR of 2.5 (range: 2.0 to 3.0), the controversy focused in a patients with a high risk of recurrence a high intensity VKA therapy (INR: 3.1 to 4.0) although did not confirm a superiority in terms of thrombotic protection, new opportunities have emerged in the treatment of arterial thrombosis with the combinations of antithrombotic drugs (ASA 325mg every days, plus thienopyridine: ticlopidine 250mg orally twice a day, or clopidogrel / GPIIb-IIIa antagonist/ anticoagulant: VKA, LMWH, fondaparinux) with a significant inhibition of thrombosis but always a remarkable and unacceptable bleeding risk, and a narrow safety window. Question: what are the very primary strong end points (death, PE or symptomatic VTE, Myocardial infarction or stroke, recurrence!), or are the inhibition of platelet functions, of signalling pathways, of atherosclerotic process monitoring. Several trials have evaluated the role of long term anticoagulation therapy, and a high intensity anticoagulation and combination therapy with a marvel issue (by 32% to 48% reduction of the risk of relapse) but a burdensome toll of side effects (bleeding by 4.8% to 8.2%). We have studied 118 patients with a tailored therapy and individual strategies selecting the disease and comorbility, the dose, the timing, the manner, the potential validity and the variance of individual responses with a significant reduction of side effects (bleeding by 0.8% to 2.4%), and a preserved therapeutic benefit (by 34% to 44% reduction of the risk of relapse). Answers: the optimal management of antithrombotic therapy is the reduction of side events, and the mainstay of treatment is to maintain patency of the vessels, but it's not so easy, certainly the main road is to have a drug made to be measured.

Disclosures:

No relevant conflicts of interest to declare.
Frequency of Minor Blood Group Antigens Among Hispanic-American Blood Donors in Southwest Texas.
Authors: Silvey Michael , Beddard Rachel , Chen Yidong , Frei-Jones Melissa
Published: October 2019

Abstract 4188

The frequency of minor blood group antigens has not been described among Hispanic blood donors. A retrospective cohort study was performed using the South Texas Blood and Tissue Center (STBTC) donor database, LifeTrak. Blood donors self-identified race and ethnicity. Caucasian and Hispanic donors were eligible. Donors who did not have minor antigen testing performed were not included. The STBTC has a high proportion of Hispanic blood donors (299047/779409, 38%), who are primarily of Mexican ancestry. Minor antigen testing was performed in 10% (74140/779409) of all donors; 8% (25394/299407) of Hispanic donors and 11% (42891/392074) of Caucasian donors. Hispanic donors were significantly more like to express blood type O Rh+ than Caucasian donors (13920/25394, 55% v 14947/74140, 35%; p<0.001). The frequency of ABO and RhD blood groups were similar to those reported previously in Caucasian and Hispanic donors (Garraty, et al. Transfusion, 2004). Of the minor antigens, expression of Rh E also differed significantly between Hispanic and Caucasian donors (4706/11744, 40% v 5416/19497, 28%; p<0.001). The prevalence of the other minor antigens were more similar and are reported in Figure 1. Complete Rh haplotypes were available in 8296 Caucasian donors and 7176 Hispanic donors. The haplotype RhDce differed significantly in 36% of Caucasians and 50% of Hispanics (3022/8296 v 3589/7176). The haplotype RhDce was previously reported as most common in African-Americans at 44% (Avent, et al. Blood, 2000). Haplotype RhDCE was found in 8% of Caucasians and 10% of Hispanics (660/8296 v 643/7176); haplotype RhDcE in 16% of Caucasians and 15% of Hispanics (1354/8296 v 1041/7176); and haplotype RhDCe was found in 39% of Caucasians and 27% of Hispanics (3260/8296 v 1903/7176). Differences exist in the frequency of minor blood group antigens among Caucasian and Hispanic blood donors in Southwest Texas.

Disclosures:

No relevant conflicts of interest to declare.