bluuebunny/crossref_metadata_2025 huggingface dataset:
Infusion of Large Number of Circulating Myeloma Cells Does Not Influence the Survival of Patients Undergoing Autologous Stem Cell Transplantation.
Authors: Abonour Rafat , Knollman Hayley , Suvannasankha Attaya , Yu Menggang , Britton Rebecca , Srivastava Shivani , Nelson Robert P. , Schwartz Jennifer E. , Robertson Michael , Cornetta Kenneth , Farag Sherif
Published: October 2019

Abstract 1224

Poster Board I-246

Multiple myeloma (MM), is a monoclonal plasma cells disorder that constitutes 10% of all hematologic malignancies. Patients with a good performance status are usually offered high-dose therapy (HDT) followed by autologous stem-cell transplantation (ASCT). HDT/ASCT is associated with complete response (CR) rates of up to 40%. Although a significant proportion of patients have a durable response after HDT/ASCT, others relapse relatively quickly and do not appear to benefit from the procedure, which may impact the overall survival (OS) of these patients. We attempt here to define the role of infusing mobilized myeloma cells on the survival of patients undergoing ASCT.

Methods

After obtaining an Institutional Review Board approval, we conducted a retrospective analysis on MM patients undergoing ASCT at our center. Data of disease status, graft characteristics, and outcome were collected. As part of the flow panel used to assess the mobilized ASC, monoclonal myeloma cells were identified by gating on a population of cells that express high levels of CD38 but do not stain or weakly with CD45 (CD38+/CD45−). OS was calculated from the date of ASCT to the time of death or last contact. Survival analysis was performed using the method of Kaplan and Meier (KP). Univariate and multivariate analysis was performed using the Cox proportional hazards model.

Results

349 patients underwent ASCT between January 1999 and April 2008. Complete data on autograft characteristics were available on 303 patients. The mobilization regimen was Cyclophosphamide and GCSF for the majority of the patients and GCSF for the more recent transplants. Melphalan at 200 mg/m2 was give 18 hours prior ASC infusion. In 199 patients there was no CD38+/CD45- cells detected. Among the 104 patients with evidence of CD38+/CD45- cells the range was 0.1-10.2 ×10 6 cells/kg and there was no difference in survival in this patient group compared to the group without evidence of contaminating myeloma cells (p= 0.54). Continuous variable analysis also did not reveal any relationship between the dose of CD38+/CD45- cells and survival (p=0.84). There may be a survival advantage after 40 moths for those receiving CD38+/CD45- cells, however the scientific rational is not well understood. Neither B2 microglobulin nor the numbers of plasma cells in the bone marrow were relevant in multivariate analysis (p= 0.42 and 0.13, respectively).

Conclusion

The presence of myeloma cells in the autograft does not appear to influence overall survival and the inclusion of CD45 and CD38 flow cytometric analysis of mobilized stem cells may not be necessary.

Disclosures

No relevant conflicts of interest to declare.
Overexpression of Rasgrf1, a Guanine Nucleotide Exchange Factor in Chronic Lymphocytic Leukemia.
Authors: Sharma Sanjai
Published: October 2019

Abstract 1253

Poster Board I-275

We performed microarray expression analysis to identify genes which are differentially expressed in chronic lymphocytic leukemia (CLL) cells. A number of genes from the cohort of maximally upregulated genes were members of the Ras superfamily of proteins function which function as switches between active GTP-complexed and inactive GDP-complexed states. One of the genes upregulated on the microarray analysis in all the CLL cells as compared to normal B cells was RASGRF1. This ras protein specific guanine nucleotide release factor stimulates the dissociation of GDP and activates Ras signaling pathway. To confirm our microarray analysis results, we performed real time PCR analysis on 35 CLL specimens and observed a 10-50 fold upregulation of rasgrf1 RNA as compared to human peripheral blood B cells. This high expression is consistently observed in all CLL specimens regardless of stage indicating that this upregulation is an early important event in the pathogenesis of CLL. Rasgrf1 protein expression was also higher in CLL cells as compared to normal B cells by western blot analysis. Interestingly the rasgrf1 gene is genomically imprinted during development in certain tissues and the expression is downregulated. Demethylation of normal peripheral blood B cells by treatment with azacytidine resulted in increased expression of rasgrf1 with no change in expression of rasgrf1 in CLL cells implying imprinting in normal B cells. Thus malignant transformation of B cells to CLL cells results in a loss of genomic imprinting and an aberrant upregulation of rasgrf1 in CLL cells. One important downstream effect of rasgrf1 upregulation is ERK activation via Ras-MAPK pathway. B cell receptor signaling in CLL results in activation of a number of pro-survival pathways including ERK which is more active in poor prognosis, unmutated immunoglobulin heavy chain CLL. Our results indicate that ERK phosphorylation is also increased in CLL specimens with rasgrf1 overexpression.

Disclosures

No relevant conflicts of interest to declare.
Dasatinib-Induced Apoptosis in Chronic Lymphocytic Leukaemia Is Abrogated by Selective Micro-Environmental Signals.
Authors: McCaig Alison M , Leach Mike , Michie Alison M
Published: October 2019

Abstract 1264

Poster Board I-286

Background

Recent advances in chronic lymphocytic leukaemia (CLL) biology indicate that a plethora of micro-environmental factors are important in promoting the pathogenesis of the disease. As B cell antigen receptor (BCR) signalling plays a critical role in CLL progression, we chose to study the effect of dasatinib, a dual src/abl tyrosine kinase inhibitor, on CLL cells, thus targeting the key, BCR-proximal tyrosine kinases Lyn and c-Abl that are over-expressed in CLL. We were interested to determine the impact of BCR-signalling directed therapy on CLL cell viability in the context of the leukaemic micro-environment.

Results

Clinically relevant concentrations of dasatinib (100 nM) both inhibited ERK-MAPK and Akt phosphorylation, and prevented calcium mobilisation following BCR crosslinking. Furthermore, dasatinib prevented up-regulation of Mcl-1 observed on prolonged BCR stimulation, abrogating the BCR-driven increase in CLL cell survival. Dasatinib induced apoptosis of CLL cells, with a mean reduction in viability of 35.2% ± 3.8% following 48 hr exposure (n=26). Neither ZAP-70 expression nor cytogenetic abnormalities were predictive of response. In addition, dasatinib exhibited synergy with both fludarabine and chlorambucil, with mean ED50 combination indices of 0.29 and 0.62 respectively. Additional micro-environmental elements responsible for the maintenance and progression of CLL include stromal or ‘nurse-like’ cells and activated T lymphocytes, the latter of which express CD40 ligand and secrete IL-4. CLL cell co-culture with the murine bone marrow stromal cell line NT-L significantly inhibited both spontaneous and dasatinib induced apoptosis. As we observed that stromal co-culture significantly increased phosphorylation of both ERK-MAPK and the Akt/mTOR target p70 S6 kinase in CLL cells, we investigated whether pharmacological inhibition these signalling pathways may re-sensitise CLL cells to dasatinib in co-culture. Both the MEK inhibitor PD98059 and PI3K inhibitor LY294002 significantly increased the level of apoptosis observed on dasatinib treatment of CLL cells in stromal co-culture. Dasatinib also retained the ability to potentiate the effects of fludarabine and chlorambucil in stromal co-culture, however, CLL cells co-cultured with NT-L cells stably transfected with CD40 ligand (CD154L cells) were resistant to all drug combinations. Furthermore, on CD154L/IL-4 co-culture, dasatinib failed to prevent up-regulation of Bcl-xL and Mcl-1, or inhibit CLL cell proliferation.

Conclusions:

While dasatinib was capable of reversing BCR-mediated survival signals, it was unable to overcome stromal-derived survival signals, indicating that combination of dasatinib with agents targeting antigen-independent micro-environmental pathways are required to effectively target CLL cells in tissue niches.

Disclosures

No relevant conflicts of interest to declare.
Polycomb Repressor Complex 2 Regulates HOXA9 and HOXA10, Activating ID2 in NK/T-Cell Lines.
Authors: Nagel Stefan , Venturini Letizia , Victor Marquez E. , Meyer Corinna , Kaufmann Maren , Scherr Michaela , MacLeod Roderick A.F. , Drexler Hans G.
Published: October 2019

Abstract 1281

Poster Board I-303

Many oncogenes code for transcription factors involved in regulation of developmental pathways. The activity of these pathways is tissue specific and restricted to certain developmental stages. Here, we searched for T-cell acute lymphoblastic leukemia (T-ALL) oncogenes which physiologically regulate differentiation of natural killer (NK) cells. NK- and T-cells are closely related lymphocytes, sharing the same early progenitors which can differentiate into either lineage. We compared expression profiles of malignant NK- and T-cell lines to identify aberrantly expressed genes in T-ALL. This analysis revealed high expression of HOXA9, HOXA10 and ID2 in NK-cell lines and in one T-ALL line, LOUCY, suggesting leukemic deregulation therein. Subsequently, we analyzed mechanisms underlying their regulation. Overexpression and chromatin immuno-precipitation experiments demonstrated that HOXA9 and HOXA10 directly activate ID2 expression. Analysis of other ALL and acute myeloid leukemia cell lines with and without mixed lineage leukemia (MLL) gene translocations demonstrated a correlated expression of HOXA9/10 and ID2, highlighting ID2 as an indirect target of MLL fusion proteins which deregulate HOXA genes. Furthermore, profiling data of genes coding for chromatin regulators of homeobox genes, including the components EZH2 and HOP of polycomb repressor complex 2 (PRC2), showed downregulation of EZH2 in LOUCY and limited expression of HOP to NK-cell lines. Subsequent treatment of T-ALL cell lines JURKAT and LOUCY with DZNep, an inhibitor of EZH2/PRC2, resulted in elevated and unchanged HOXA9/10 expression levels, respectively, confirming repressive activity of EZH2 in T-cells. Additionally, profiling data and overexpression analysis indicated that reduced expression of E2F cofactor TFDP1 contributed to the lack of EZH2 in LOUCY. Forced expression of HOP in JURKAT cells resulted in reduced HOXA10 and ID2 expression levels, suggesting enhancement of PRC2 repression. Taken together, our results show that major differentiation factors of the NK-cell lineage, including HOXA9, HOXA10 and ID2, were (de)regulated via PRC2 and may contribute to T-cell leukemogenesis.

Disclosures

No relevant conflicts of interest to declare.
Findings of Thrombophilia Evaluation and Impact On Management in Asymptomatic Children with a Proximate Family History of Early Thromboembolism: An Institutional-Based Prospective Inceptional Cohort Study.
Authors: Calhoon Meghan J. , Pounder Elizabeth , Manco-Johnson Marilyn J. , Goldenberg Neil A.
Published: October 2019

Abstract 1289

Poster Board I-311

ABSTRACT

Background and Objective

Although the overall incidence of venous thromboembolism (VTE) is low in children, risk is greatly increased by a proximate family history of early TE. The principal aims of the present study were to determine among such children: (1) the prevalence of thrombophilia; and (2) the frequency of recommended changes in management resulting from thrombophilia evaluation.

Methods

Laboratory thrombophilia investigation was performed in 56 children (≤ 18 years of age) with a first- or second-degree family history of TE before age 55 years, but without personal history of TE, who were consecutively enrolled in an institutional-based prospective inceptional cohort study of pediatric thrombosis/thrombophilia between March 1, 2006 and June 1, 2009. VTE risk factors, family history, thrombophilia findings, and management recommendations were systematically collected.

Results

The frequencies of all thrombophilia traits were higher than expected for the general population; factor V (FV) Leiden, elevated factor VIII activity, elevated lipoprotein(a) concentration, and antiphospholipid antibody positivity were most common (Figure 1). Among 32 children who underwent complete laboratory evaluation, 34% had ≥2 traits (Figure 2). Thrombophilia testing led to a change in recommended management in 71% of subjects, principally consisting of transient anticoagulant prophylaxis during periods of heightened clinical risk for VTE. Furthermore, recommendation against future use of estrogen-containing oral contraceptive pills was made in 32% of females based upon FV Leiden testing alone, as compared to 64% in whom additional laboratory evaluation was performed (P=0.02).

Conclusions

Multi-trait thrombophilia is common among asymptomatic children who have a proximate family history of early TE. In this cohort study, comprehensive thrombophilia testing in such children informed future use of estrogen-containing oral contraceptives among females, and often resulted in a recommendation for antithrombotic prophylaxis during high-risk situations. Future studies should evaluate the safety and efficacy of risk-stratified primary prevention strategies for pediatric VTE.

Disclosures

Manco-Johnson: Baxter BioScience: Honoraria; Bayer HealthCare: Honoraria; CSL Behring: Honoraria; NovoNordisk: Honoraria; Octapharma: Honoraria.
Immune-Modulatory Effects of Mesenchymal Stromal Cell Infusions for the Treatment of Factor VIII Inhibitor in Hemophilia A.
Authors: Matsui Hideto , Harpell Lori , Powell Sandra , Rafei Moutih , Galipeau Jacques , Hough Christine , Lillicrap David
Published: October 2019

Abstract 1299

Poster Board I-321

The current most serious treatment-related complication in hemophilia A is the development of antibodies to FVIII following exposure to FVIII replacement therapy. We have previously demonstrated that the injection of syngeneic mesenchymal stromal cells (MSCs) into hemophilia A mice with FVIII antibodies lead to a robust decrease in FVIII specific IgG levels because the secretome of MSCs suppresses plasma cell immunoglobulin production, induces plasmablast proliferation, and leads to IL-10-mediated blockade both in vitro and in vivo. Therefore, we wanted to pursue this study in a large animal model. In the current study, we harvested MSCs from bone marrow aspirates obtained from 2 hemophilia A dogs with both human and canine FVIII inhibitors. The isolated MSCs were expanded ex vivo for the infusions. Prior to the infusions, we performed in vitro characterization of the canine MSCs and found that the cells secrete a wide range of cytokines and chemokines including CC chemokine ligand 2 (CCL2) and CCL2 that has been cleaved to its truncated inhibitory form by proteolysis with matrix metalloproteinases (MMPs). These results are identical to those seen in the previous mouse experiments. Before the MSC infusions, the hemophilia A dogs with inhibitors were immunized by multiple intravenous infusions of both human FVIII and canine cryoprecipitate to further boost the development of FVIII antibodies. Expanded autologus MSCs (4.5-6.0×106 cells/Kg) were infused intravenously into the first dog twice, with a month in between each injection. After the second infusion, the titer of anti-human FVIII inhibitory activity was significantly decreased from 6.2 to 1.9 BUs and a transient but significant decrease from 3.5 to 2.2 BUs against canine FVIII. Second MSC infusion trial is currently ongoing in a second dog. In parallel with in vivo study, the inhibitory response mediated by MSCs on the FVIII antibody producing B cells was assessed by ELISPOT assay. In conclusion, MSCs may play an immunosuppressive role in modulating Immunoglobulin production by plasma cells via MMP processing of paracrine CCL2 secretion. This may represent a novel cellular therapy for attenuation of pathological humoral responses such as anti-FVIII antibody development.

Disclosures

No relevant conflicts of interest to declare.
Heparin Forms Macromolecular Complexes with Protamine and Lysozyme.
Authors: Chudasama Shalini , Espinasse Benjamin , Wiesner Mark R , Arepally Gowthami M
Published: October 2019

Abstract 1316

Poster Board I-340

The immune response in Heparin-Induced Thrombocytopenia (HIT) is directed to and initiated by large multimolecular complexes of Platelet Factor 4 (PF4) and heparin. We, and others, have previously shown that PF4 and heparin multimolecular assembly occurs through colloidal interactions, wherein heparin, a negatively charged polymeric compound, facilitates macromolecular assembly by binding and neutralizing PF4's positive charge (Suvarna, Blood 2007). In these same studies, we also demonstrated that changes in the molar ratios of the two reactants result in PF4/heparin (PF4:H) complexes with markedly altered biophysical properties and immunogenicity. Because PF4:H electrostatic interactions are non-specific, we hypothesized that other positively charged proteins would exhibit similar colloidal interactions with heparin. To test this hypothesis, we selected two positively charged proteins (protamine and lysozyme) and studied heparin-dependent complex formation by spectrophotometry (A280nm), and zeta potential (Zeta Sizer, Malvern, UK). Protamine sulfate (250, 125, 62.5, 31.2, 15.6 and 7.8 mcg/mL; Mw 5.1kDa) and lysozyme (1000, 500, 250 and 125 mcg/mL; Mw 14.3kDa) were mixed with various heparin concentrations (0-160 U/mL; activity 140U/mg; Mw 12kDa) and biophysical properties characterized by both instruments. Both protamine and lysozyme showed heparin-dependent complex formation, with peak particle formation occurring over a range of heparin concentrations (2-25 U/mL ) for both compounds. For protamine, particle formation was maximal at protamine:heparin (Pr:H) molar ratios of ∼2.5-3:1, whereas lysozyme formed peak particles at lysozyme;heparin (Ly:H) molar ratios of ∼5:1 (See figure). As with PF4:H complexes, size of complexes was dependent on mass amounts of protamine or lysozyme, with particle size increasing or decreasing in proportion to the amounts of protamine or lysozyme available for complex formation. These findings indicate that heparin is capable of forming macromolecular complexes with other proteins through charge dependent interactions. Additional in vitro and in vivo studies are underway to determine if Pr:H or Lys:H complexes exhibit cross-reactivity with PF4/heparin antibodies and if complex formation is associated with immunological consequences.

Disclosures

No relevant conflicts of interest to declare.
ATP Acts as Danger Associated Molecular Pattern and Enhances Acute Graft-Versus-Host Disease Severity Via P2×7-R.
Authors: Wilhelm Konrad , Müller Tobias , Ganesan Jayanthi , Dürr Christoph , Gerlach Ulrike , Zerweck Alf , Finke Jürgen , Idzko Marco , Zeiser Robert
Published: October 2019

Abstract 1336

Poster Board I-358

Conditioning prior allogeneic hematopoietic cell transplantation causes local tissue injury. Cellular molecules that are released upon cell stress, injury or cell death can act as potent danger associated molecular patterns (DAMP). Nucleotides like ATP are ideal candidates to serve as such indicators of cell damage, since they are present in the extracellular environment in the nanomolar range under physiological conditions but are released upon unphysiological cell death which causes activation of purinergic receptors. The role of purinergic signaling in alloantigen driven immune responses such as graft-versus-host disease (GvHD) is unclear. We found that ATP levels in the peritoneal fluid increased when GvHD was present in human and mice. Detection of extracellular ATP with a luciferase based in vivo detection system demonstrated early ATP release from the gastrointestinal tract. Blockade of multiple purinergic receptors on T cells or ATP neutralization during GvHD development reduced disease severity and proinflammatory cytokine production significantly. Gene expression analysis of different P2R in GvHD target organs identified the P2X7(R)receptor to be increasingly expressed. P2X7R−/− recipients developed less severe GvHD as compared to wildtype mice. This was paralleled by the induction of STAT5 signaling with increased numbers of Foxp3 positive regulatory T cells while STAT1 phosphorylation and IFN-γ production was reduced. Despite P2X7R blocking, T cells were still able to reconstitute the lymphoid compartment with a polyclonal intact TCR repertoire analyzed by spectratyping DNA sequence analyses of the CDR3 region and to reject established B-cell lymphoma. Therefore, DAMPs such as endogenous nucleotides may not be required for anti-tumor activity but dominantly trigger acute GvHD. Blockade or genetic deficiency of P2X7R in BMT recipients conferred GvHD protection without loss of GvL effects, which has important clinical implications given the availability of P2X7R inhibitors.

Disclosures

No relevant conflicts of interest to declare.
Mutual Activation and Expansion of Donor CD4 + T Cells and B Cells in Transplants Play a Critical Role in the Initiation of Chronic Graft-Versus-Host Disease.
Authors: Young James Sundblom , Zhao Dongchang , Yi Tangsheng , Liu Hongjun , Zeng Defu
Published: October 2019

Abstract 1342

Poster Board I-364

Chronic graft versus host disease (GVHD) is an autoimmune-like disease, in which both donor CD4+ T and B cells play important roles in the pathogenesis. However, it is unclear how donor CD4+ T and B cells interact in the context of chronic GVHD. In our current studies, we found that, in a new chronic GVHD model of MHC-matched DBA/2 donor to BALB/c host, depletion of donor CD4+ T cells in transplants prevented donor B220+ B cell upregulation of co-stimulatory molecules (i.e. B7.1, B7.2, and MHC II), prevented donor B cell differentiation into syndecan+ IgG anti-dsDNA autoantibody-producing plasma cells, and prevented the induction of chronic GVHD. In addition, we found that donor CD4+ T cells were able to drive both marginal zone B (AA4.1−B220+CD1dhiCD23lo) and follicular B (AA4.1−B220+CD23hiCD1dlo) cells to become IgG autoantibody-producing cells. On the other hand, depletion of donor B220+ B cells in transplants prevented expansion of donor-type CD4+ T cells that proliferated in response to donor DC stimulation, prevented the skewing of TCR CDR3-length of the donor CD4+ T cells as revealed by TCR spectratyping, and prevented induction of chronic GVHD. These results indicate that donor CD4+ T and B cells mutually activate each other in the chronic GVHD recipients; alloreactive donor CD4+ T cells activate and drive donor B cell differentiation into IgG autoantibody producing cells, in turn, donor B cells mediate the expansion and TCR-spreading of autoreactive donor CD4+ T cells. Therefore, donor CD4+ T and B cells in transplants orchestrate the development of chronic GVHD. This work is supported by NIH R01 AI066008.

Disclosures

No relevant conflicts of interest to declare.
Elevated Pre-Treatment Serum Immunoglobulin Free Light Chains (FLC) Are Associated with Poor Event-Free and Overall Survival in Diffuse Large B-Cell Lymphoma (DLBCL).
Authors: Maurer Matthew J , Micallef Ivana N , Katzmann Jerry A , Nikcevich Daniel , Witzig Thomas E
Published: October 2019

Abstract 136

Background:

The serum free light chain (FLC) assay quantitates free kappa and free lambda immunoglobulin light chains. This assay has prognostic value in MGUS, multiple myeloma (MM), solitary plasmacytoma, and AL amyloidoisis, and has been incorporated in response criteria for both MM and AL amyloidosis. A percentage of non-Hodgkin's lymphoma (NHL) patients also present with abnormal FLC concentrations and recent data suggest that AIDS patients with elevated serum FLC are at higher risk of developing NHL. Here we assess the impact of FLC in a cohort of patients with diffuse large B-cell lymphoma (DLBCL) enrolled on a cooperative group clinical trial.

Methods:

Newly diagnosed DLBCL patients were treated with epratuzumab + R-CHOP (ER-CHOP) on NCCTG clinical trial N0489. Serum FLC was quantitated prior to treatment and after cycles 2 and 6 using the Freelite FLC assay (The Binding Site, Ltd., Birmingham, UK). Patients were followed per clinical trial protocol for event-free (progression, retreatment, or death due to any cause) and overall survival (EFS and OS, respectively).

Results:

107 patients were enrolled on the trial. 80 patients had a pre-treatment serum draw and a central pathology confirmed diagnosis of DLBCL, of which 47 had a post-cycle 2 sample (C2) and a 54 had a post-cycle 6 sample (C6). At a medium follow-up of 25 months (range 7-39), 22 patients (28%) had an event and 17 patients died (21%). Prior to treatment 23 patients (29%) had abnormal kappa concentrations (all elevated), 16 (20%) had abnormal lambda concentrations (11 elevated, 5 decreased), and 9 (11%) had an abnormal kappa/lambda ratio. FLC concentrations were significantly reduced in patients during treatment, with a median reduction in kappa (C2: 46%, C6: 64%) and lambda (C2: 44%, C6: 49%), all p<0.0001. Elevated FLC prior to treatment was highly associated with both OS (logrank p=0.009) and EFS (logrank p=0.006); these associations remained significant after adjusting for IPI (both p = 0.01).

Conclusions:

A significant percentage of DLBCL patients present with abnormal FLC concentrations. Kappa and lambda are significantly reduced for most patients during treatment. Elevated pre-treatment FLC concentrations are associated with inferior EFS and OS in DLBCL and this association is independent of the IPI. A follow-up study of FLC and prognosis is currently underway in a cohort of 1500 NHL patients from the Mayo Clinic and University of Iowa SPORE.

Disclosures:

No relevant conflicts of interest to declare.
The C677T Methylenetetrahydrofolate Reductase Polymorphism and Insulin Resistance in Childhood Cancer Survivors.
Authors: Bishop Lisa Ann , Steffen Lyn M , Tsai Alex , Hanson Naomi , Baker K. Scott , Dengel Donald R. , Kelly Aaron , Sinaiko Alan R. , Petryk Anna , Moran Antoinette , Perkins Joanna Lee , Lundsford-Lee Jill , Steinberger Julia
Published: October 2019

Abstract 1400

Poster Board I-422

Introduction:

Childhood cancer survivors have increased risk for cardiovascular disease and insulin resistance. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and low folate are associated with higher levels of homocysteine and changes in methylation status; these factors, in particular the TT and CT genotypes have been associated with insulin resistance in animal and human models. The CT genotype is present in about 25 % of the healthy US population. Vitamin B12 is an important co-factor in this association. The homocysteine/methionine ratio has been used as an indirect marker of methylation status and MTHFR function.

Population and Methods:

This analysis includes children (n=156) who survived ≥ 5-yrs following diagnosis of acute lymphoblastic leukemia (ALL) (n=55), acute myeloid leukemia (AML) (n=4), and non-Hodgkin's lymphoma (NHL) (n=13), central nervous system tumors (38) and other cancers (n=46). Mean age at diagnosis was 10.3 yrs (5.7-15.8) and mean age at evaluation was 15.0 yrs (9.9-17.9). Anthropometric measurements, blood pressure (BP), fasting glucose, insulin, lipids, folate, vitamin B12, homocysteine, and methionine were collected. Insulin resistance was assessed by euglycemic hyperinsulinemic clamp, adjusted for lean body mass (low Mlbm represents insulin resistance, less than 50% of distribution). Genetic polymorphisms, of MTHFR CC (wildtype) CT (heterozygous) and TT (homozygous) were identified; comparisons between MTHFR polymorphisms were adjusted for age, gender, and Tanner stage.

Results:

CC genotype was present in 44%, CT in 47.3 %, and TT in 8.7 % of survivors. Folate and B12 levels were lowest in the TT group, although not statistically significant (P value >0.05). Insulin resistance was most prevalent in the CT group and least prevalent in the TT group. The homocysteine/ methionine ratio was lowest in the CT group and highest in the TT group. Measures of adiposity were similar in all three groups (Table).

Conclusion:

This study suggests an increased frequency of the CT genotype in this study population of childhood cancer survivors compared to the healthy US population. Insulin resistance was most prevalent in the CT group; however, this was not associated with low levels of folate, B12, or high homocysteine/methionine ratio. The low frequency of insulin resistance in the TT group likely reflects the small number of participants with this genotype. Further study of these variables in larger populations is needed to provide sufficient power in assessing these relationships in childhood cancer survivors.

Disclosures:

No relevant conflicts of interest to declare.
Inpatient Geriatric Assessment Detects Impairment Among Older Adults Receiving Induction Chemotherapy for Acute Myelogenous Leukemia.
Authors: Klepin Heidi D , Geiger Ann M , Williamson Jeff , Kritchevsky Stephen , Tooze Janet A , Ellis Leslie Renee , Levitan Denise , Isom Scott , Powell Bayard L.
Published: October 2019

Abstract 1401

Poster Board I-423

Background:

Acute myelogenous leukemia (AML) is a disease which largely affects older adults, for whom optimal therapy is unclear. Evidence-based strategies to identify those older adults who may tolerate and benefit from standard therapies are lacking.

Objective:

Test the utility of a bedside geriatric assessment (GA) to detect impairment in multiple geriatric domains among older adults initiating induction chemotherapy for AML.

Methods:

Ongoing prospective study of patients ≥60 years of age with newly diagnosed AML and planned induction chemotherapy admitted to Wake Forest University. Bedside geriatric assessment (GA) was performed during inpatient work-up for AML. GA measures included the Modified Mini-Mental Status Exam (3MS), Center for Epidemiologic Studies Depression Scale (CES-D), Distress thermometer, Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI), Pepper Assessment Tool for Disability ([PAT-D], includes self- reported activities of daily living (ADL), instrumental activities of daily living (IADL), and mobility questions), Short Physical Performance Battery ([SPPB], includes timed 4-meter walk, chair stands, standing balance), and grip strength.

Results:

26 of 29 eligible patients enrolled between 1/2009 and 8/2009. The median age was 68 (range 60-82) years, and 42.3% were female. Prior myelodysplastic syndrome was present in 34.6%, with intermediate or poor-risk cytogenetics in 95.6%. Baseline laboratory measures included white blood cell count (mean 17.3×103/mm3, SD 25.0×103), hemoglobin (mean 9.2g/dl, SD 1.5), lactate dehydrogenase (mean 282.4 U/L, SD 168.8). Mean baseline GA scores included: 3MS 83.0 (SD 14.7), CES-D 9.4 (SD 9.3), Distress 3.8 (SD 3.4), HCT-CI 1.3 (SD 1.6), PAT-D 1.4 (SD 0.7), SPPB 7.1 (SD 3.9), grip strength 32.4 kilograms (SD 9.2). Although 84.6% of subjects had an Eastern Cooperative Oncology Group (ECOG) Performance score <2, a substantial proportion met criteria for impairment in multiple geriatric domains.

Conclusions:

GA measures detect abnormalities which are not adequately reflected by the ECOG performance score in older adults with AML. Future analyses from this ongoing study will evaluate whether these abnormalities are independently associated with treatment-related morbidity and survival.

Disclosures:

No relevant conflicts of interest to declare.
Diet, Lifestyle and Venous Thromboembolism (VTE) in Thai Population.
Authors: Rojnuckarin Ponlapat , Bhoopat Lantarima , Hiransuthikul Narin , Intragumtornchai Tanin
Published: October 2019

Abstract 1414

Poster Board I-437

Introduction:

Previous studies demonstrated that the incidence of venous thromboembolism (VTE) was very low among Thais (Lancet. 1975; 1: 1357-8, Arch Intern Med. 1988; 148: 1349-53). However, recent investigations in Asian countries strongly indicated that VTE is currently much more common, approaching rates in the western countries. Meanwhile, the latest National Health Surveys showed the inadequate vegetable and fruit intakes, as well as an obvious rise in prevalence of obesity in Thai population. Therefore, changing diet and behaviors are suspected to contribute to this marked increase in the VTE incidence.

Patients and Methods

The case-control study was conducted. Cases were objectively confirmed venous thromboembolism. Patients with underlying cancer, antiphospholipid syndrome and arterial thrombosis were excluded. Controls are age- and sex-matched healthy volunteers. Body mass indices, history of alcohol intake, smoking and exercise were obtained. Food consumptions were interviewed using a food frequency questionnaire modified from the Thailand National Health Examination Survey III previously validated in Thai population.

Results:

There were 97 cases and 195 controls. The mean age was 54.6 yr, ranging from 17-93 yr, and 70% were female. VTE was significantly associated with low vegetable intakes (below 3.5 standard servings per day) compared with controls (Odd ratio [OR] 2.5, 95% confidence interval [CI] 1.37-4.67), while there was no difference in fruit consumption (p values =0.53). Notably, low fish intakes (below 0.1 serving per day, OR 3.9, 95%CI 1.58-9.71) and having spicy food less than once a week (OR 1.9, 95%CI 1.15-3.18) also increased the risk. The meat, fat, carbohydrate, fast food or alcohol consumptions were similar. In addition, VTE was associated with overweight (OR 2.1, 95%CI 1.21-3.62) and obesity (OR 3.1, 95%CI 1.46-6.74, p values = 0.002 and 0.001, respectively). Furthermore, estrogen uses also increased the risk of VTE (OR 3.7, 95% CI 1.05-13.20, p=0.02), while smoking and lack of exercise did not.

Conclusions:

Low vegetable, fish and spicy food intakes, as well as obesity and hormonal uses, are the risk factors for VTE in Thai population.

Disclosures:

No relevant conflicts of interest to declare.
Impact of Physician to Physician Interactions Utilizing Case Based Learning Workshops to Accelerate Accrual to Lymphoma Trials.
Authors: Eckardt John , Ku Nora , DeMaggio Annemieke , Peracha Omair , Levonyak Nick , Reese Merrick H. , Levonyak Mark , Jain Vinay
Published: October 2019

Abstract 1418

Poster Board I-441

Introduction:

Seventy percent of clinical trials in the United States are delayed by one to six months due to enrollment challenges. Barriers to accrual are site specific as well as protocol specific. Site specific challenges include perceptions of patient ineligibility and cumbersome screening processes. Protocol barriers include complexity of inclusion and exclusion criteria. Coomis et al (J Onc Prac 2009; 5:50) reported that 73% of overall clinical trial awareness was generated by physician interest. Therefore, the familiarity of investigators with each trial is crucial to optimizing patient accrual. The standard protocol initiation process relies on investigators and staff to attend an investigator's meeting. However, this approach does not focus on actual clinical patient presentations to determine trial eligibility or exclusion. As a result, many investigators may overlook key criteria for eligibility thus losing patients to enrollment. We have previously shown that interventions directly with PIs to increase PI awareness of inclusion/exclusion criteria of a clinical trial results in improved trial accrual (ASCO 2009, abs 6613).

Methods:

Investigator focused Accrual Workshops (AW) are used to increase patient enrollment to oncology clinical trials. While a standard investigator meeting includes protocol review, AW first create a compelling scientific story to re-engage the investigators in the trial. The key to these AW is the use of case-based learning to highlight the clinical and scientific rationale of the trial as opposed to general protocol review.

Results:

Between May 2008 and May 2009, 14 AW were conducted for 5 separate studies including 2 lymphoma trials. The AW with less than 120 days of follow up (n=5) show no significant impact although there was a trend toward increased accrual. In those with more than 120 days of follow up (n=9), the mean increase in accrual was 108% with increased accrual following every AW (Figure 1). After those 9 AW, patient accrual per month increased 1.65 fold on average. Analysis of the 2 lymphoma clinical trials demonstrates a significant increase in accrual following AW of 230% and 40%, respectively.

Conclusion:

AW using physician to physician clinical case-based learning provide an effective means of educating investigators and research staff in the identification of patients who meet the criteria for participation in clinical trials. The impact of AW on clinical trial accrual is best seen over time and they are effective in lymphoma clinical trials as well as others. After every AW with more than 120 day follow up, accrual was accelerated.

Disclosures:

No relevant conflicts of interest to declare.
Arterial and Venous Thrombosis in Monoclonal Gammopathy of Undetermined Significance and Multiple Myeloma: A Population-Based Study.
Authors: Kristinsson Sigurdur Y , Pfeiffer Ruth , Bjorkholm Magnus , Goldin Lynn R , Schulman Sam , Blimark Cecilie , Mellqvist Ulf-Henrik , Wahlin Anders , Turesson Ingemar , Landgren Ola
Published: October 2019

Abstract 1872

Poster Board I-897

Background

Patients with multiple myeloma (MM) have an increased risk of venous thrombosis. Additionally, MM has been associated with arterial thrombosis. Interestingly, excess risk of venous thromboembolism has been observed among patients with monoclonal gammopathy of undetermined significance (MGUS).

Methods

Using population-based data from Sweden, we assessed the risks of venous and arterial thrombosis in 18,627 MM and 5,326 MGUS patients, compared to 70,991 and 20,161 matched controls, respectively. Hazard ratios for thrombosis, at 1, 5, and 10 years follow-up were calculated using Cox proportional hazard models.

Results>

At 1, 5 and 10 years after MM diagnosis, there was an increased risk of venous thrombosis: hazard ratios (95% confidence intervals) were 7.5 (6.4–8.9), 4.6 (4.1–5.1), and 4.1 (3.8–4.5), respectively. The corresponding results for arterial thrombosis were 1.9 (1.8–2.1), 1.5 (1.4–1.6), and 1.5 (1.4–1.5). At 1, 5 and 10 years after MGUS diagnosis, hazard ratios were 3.6 (2.6–4.9), 2.2 (1.8–2.6), and 2.1 (1.8–2.5) for venous thrombosis. The corresponding risks for arterial thrombosis were 1.7 (1.5–1.9), 1.3 (1.2–1.4), and 1.3 (1.3–1.4). IgG/IgA (but not IgM) MGUS patients had increased risks for venous and arterial thrombosis with hazard ratios 4.5 (2.8–7.2) and 1.6 (1.3–1.9) 1 year and 2.2 (1.7–2.8) and 1.2 (1.1–1.4) 5 years after diagnosis. Risks for thrombosis did not vary by M-protein concentration (above/below 10.0 g/L) at diagnosis. MGUS patients with (versus without) thrombosis had no excess risk of MM progression.

Conclusion

In this large study including more than 5,000 MGUS patients and 18,000 MM patients, and their matched controls, we found that both MGUS and MM patients had an increased risk of venous as well as arterial thrombosis. Among MGUS patients, an excess risk of thrombosis was observed in patients with IgG/IgA MGUS, but not IgM. Future studies are needed to clarify underlying mechanisms of our findings. Such efforts will be of relevance for physicians managing MGUS and MM patients and have potential implications for the development of better thrombosis prophylaxis strategies.

Disclosures:

Mellqvist: Johnson and Johnson: Research Funding; Celgene: Speakers Bureau; Jansen-Cilag: Speakers Bureau.
Improving Outcomes in Patients with Renal Failure Secondary to Multiple Myeloma: Results From ChAR2M2.
Authors: Hutchison Colin , Airia Parisa , Cook Mark , Grima Daniel
Published: October 2019

Abstract 1875

Poster Board I-900

Study purpose:

To explore how free light chain (FLC) removal by high cut-off haemodialysis (HCO-HD) has been adopted into clinical practice for the management of renal failure secondary to multiple myeloma. Describing treatment patterns and the laboratory and clinical outcomes associated with its use.

Methods:

A chart audit of patients treated with FLC removal by HCO-HD, using the Gambro HCO 1100 dialyser, was performed in 16 dialysis centers across 9 countries. Patient demographics, treatment patterns and dialysis side-effects were recorded. In addition, the following outcomes were measured: dialysis independence and reductions in serum FLCs concentrations at 12 and 21 days.

Results:

Data for 66 patients was entered. Patients had an average age of 65.1 (SD×10.1); 42 of them (63.64%) were male and 24 (36.36%) were female. Sixteen (24%) presented with relapsing myeloma and 50 (76%) had de novo disease. On average, each patient received 13 HCO-HD sessions (SD×8). Forty-one patients became dialysis independent (62.12%), after an average of 12 sessions. Dialysis related side-effects were reported in 6% of all patients. Forty patients (60.61%) were reported to have a sustained reduction in serum FLC concentrations by day 12. By day 21 this had increased to forty-one (62.12%). Among the patients who achieved a sustained reduction in serum FLC concentrations, 28 (70%) had a decline in FLC levels of more than 50% by day 12 and 34 (82.93%) by day 21. Among patients who achieved sustained reduction of more than 50% in serum FLC concentrations by day 12, 75% became dialysis independent. In comparison only 53% of those with a reduction of less than 50% became dialysis independent (p×0.007). Furthermore, among patients who achieved sustained FLC reduction of greater than 75%, 81% became dialysis independent. The rate of dialysis independence was also significantly higher in patients with de novo disease compared with those with relapsing myeloma (64% versus 56%, p×0.04).

Conclusion:

Free light chain removal by HCO-HD was well tolerated and associated with a very high rate of dialysis independence in patients with renal failure secondary to multiple myeloma. Rates of renal recovery were greater in patients with de novo myeloma and those who achieved an early reduction in serum FLC concentrations.

Disclosures:

No relevant conflicts of interest to declare.
Pharmacodynamic (PD) Biomarker Assay Validation for SB1518, a Novel Oral JAK2 Inhibitor in Phase 1 Clinical Trials for Advanced Leukemias, Myeloproliferative Diseases and Lymphoma.
Authors: Hart Stefan , Goh Kee Chuan , Tan Yong Cheng , Chithra Amalini , Wood Jeanette
Published: October 2019

Abstract 1888

Poster Board I-911

Introduction:

Abnormalities in JAK2 and FLT3 kinases are reported in various hematological malignancies and may underlie the pathogenesis of these diseases. An activating mutation of JAK2, namely JAK2V617F is the most common mutation in bcr-abl-negative chronic myeloproliferative disorders (MPDs). Activation of wild type JAK2 has been reported in Hodgkin lymphoma (HL) and primary mediastinal large cell Non-Hodgkin lymphomas (NHL) due to loss of Suppressor of Cytokine Signaling (SOCS)-1 gene. Abnormalities in FLT3 are present in ∼30% of acute myelogenous leukemias (AML). SB1518 is a potent inhibitor of both JAK2 (IC50 = 22 nM) and its JAK2V617F mutant (IC50 = 19 nM) as well as FLT3 (IC50 = 22 nM) and it mutant D835Y (IC50 = 6 nM). As a consequence, SB1518 inhibits the proliferation of human leukemia and lymphoma cell lines dependent on either JAK2 or FLT3 activation (IC50 =35–240 nM), and has antitumor activity in nude mouse models of FLT3- (MV4-11) or JAK2-dependent (BaF3-JAK2V617F) leukemia. SB1518 is currently being evaluated in Phase 1 clinical trials for advanced leukemias, MPDs and lymphoma. We describe here the development and assessment of biochemical biomarkers to assess the pharmacodynamic (PD) efficacy of SB1518 in the phase I clinical trials.

Methods and Results:

Sensitive flow cytometric and quantitative Western-blot assays were developed for measuring downstream JAK2 and FLT-3 signaling; namely STAT5/3 phosphorylation in tumor tissue, fixed cells from whole blood or lysed PBMCs. These assays were validated by demonstrating target inhibition after ex vivo treatment of PBMCs from healthy human donors and in blood cells and tumor tissue after oral dosing of normal and tumor bearing nude mice with SB1518. Initial data obtained from analysis of whole blood and PBMCs from patients treated with SB1518 in the ongoing Phase 1 clinical trials demonstrate target inhibition even at the lowest dose level of 100 mg/day on the first day of oral dosing.

Conclusion:

In summary, we have developed and quantitative biomarker assays and applied them to demonstrate PD target efficacy of SB1518 in animal tumor models as well as patients in ongoing phase 1 clinical trials.

Disclosures:

Hart: S*BIO PTE LTD: Employment, Equity Ownership. Goh:S*BIO PTE LTD: Employment. Tan:S*BIO PTE LTD: Employment. Chithra:S*BIO PTE LTD: Employment. Wood:S*BIO PTE LTD: Employment.
Trends in the Incidence of HIV-Related Hematologic Malignancies in the Era of Combination Antiretroviral Therapy and Predictors of HIV-Related Non-Hodgkin's Lymphoma Development and Survival.
Authors: Taggart Linda R , Isogai Pierre K , Risebrough Nancy , Mittmann Nicole , Rachlis Anita R , Imrie Kevin R , Cheung Matthew C
Published: October 2019

Abstract 1916

Poster Board I-939

Introduction:

Since the introduction of combination antiretroviral therapy (cART), the incidence rates of non-Hodgkin's lymphoma (NHL) and primary central nervous system lymphoma (PCNSL) have declined; however, less is known about the rates of other hematologic malignancies such as Hodgkin lymphoma (HL) and multiple myeloma (MM). We aimed to study changes in the incidence and outcomes of hematologic malignancies (HMs) in the pre- and post-cART eras.

Methods:

A retrospective analysis of The Ontario HIV Treatment Network Cohort Study (OCS) was performed. The OCS is an ongoing prospective study of HIV-infected adults from 11 sites throughout Ontario, Canada. Incidence rates of HMs were calculated for the pre- (<1997) and post-cART (≥ 1997) eras and compared using Poisson regression analysis. Median survival for each HM was calculated using Kaplan Meier techniques and compared using the logrank test. Predictors of NHL and death from NHL including age, sex, CD4 count, viral load, previous AIDS-defining illness, cART era and duration of HIV infection were evaluated using Cox proportional hazard models. All variables except sex were considered time dependent variables.

Results:

The OCS database included 4118 individuals with 41978 person-years of follow up over 28 years (1980-2008). There was no significant difference in the incidence of HM in the pre- and post-cART eras (3.6 versus 4.1 cases per 1000 person-years, p-value=0.49) although incidence of PCNSL trended downward (0.8 versus 0.4 cases per 1000 person-years, p-value=0.13) and incidence of HL trended upward (0.1 versus 0.4 cases per 1000 person-years, p-value=0.08). Those with HL had the longest median survival, followed by NHL and PCNSL (63, 39 and 4 months respectively). Predictors of NHL development included low CD4 count, high viral load and pre-cART era. Predictors of death following NHL diagnosis were low CD4 count, previous AIDS-defining illness and longer duration of HIV infection.

Conclusion:

Since the introduction of cART, the overall incidence of HM has not significantly changed in this cohort. However, as fewer individuals in the cART era develop low CD4 counts, high viral loads and AIDS-defining illnesses, reduced incidence of NHL in this cohort and improved survival following NHL may become apparent.

Disclosures:

No relevant conflicts of interest to declare.