bluuebunny/crossref_metadata_2025 huggingface dataset:
Pretreatment Serum Level of Osteopontin and Vascular Endothelial Growth Factor Might Have a Prognostic Value in Patients with Diffuse Large B-Cell Lymphoma
Authors: Nacinovic Antica Duletic , Juranovic Tajana , Valkovic Toni , Petranovic Duska , Host Ivan , Fisic Elizabeta , Prolic Andjela , Lucin Ksenija , Stifter Sanja , Jonjic Nives , Labar Boris
Published: October 2019

Abstract 1609

Background:

Angiogenesis is gaining importance in hematological malignancies; it is regulated by a balance of various enhancing and inhibiting angiogenic factors. However, studies related to the prognostic value of angiogenic factors and aggressive Non-Hodgkin lymphomas are limited compared to solid tumors. The aim of this study was to determine pretreatment serum level of vascular endothelial growth factor (VEGF) and osteopontin (OPN) in patients with diffuse large B cell lymphoma (DLBCL) and to investigate whether these factors provide prognostic information.

METHODS:

We measured pretreatment serum levels of VEGF and OPN by Enzyme-Linked Immunosorbent Assay (ELISA) in 67 patients newly diagnosed as diffuse large B-cell lymphoma and in 30 healthy controls. All patients were treated with rituximab-CHOP chemotherapy.

RESULTS:

The serum OPN levels were found elevated in untreated DLBCL patients compared to controls: in newly diagnosed patients it ranged from 25 to 238 pg/ml; median 94.2 pg/ml while in the healthy controls it ranged from 13 to 46.5 pg/ml; median 30.0 pg/ml (P=0.00008). There were significant differences in the serum VEGF levels between DLBCL patients and controls (median 480.96 pg/ml vs. 163.8 pg/ml, P=0.001). Serum OPN levels higher than the median level were related to advanced Ann Arbor stage (P=0.026), International Prognostic Index of 2 or higher (P=0.005), ECOG III-V (P=0.004). The complete remission rate after treatment was higher in patients with low OPN serum levels than in those with high OPN serum levels (67.5% versus 32.4%, P=0.002). Elevated serum levels of OPN were strongly associated with shorter overall survival (P=0.007) and event-free survival (P=0.04). In multivariate analysis with International Prognostic Index criteria, OPN remained a significant predictor for overall survival (P=0.033). VEGF level was significantly correlated with age (P=0.01) and serum lactate dehydrogenase level (P=0.02), but not strongly correlated with other potential prognostic factors, and it failed to show prognostic significance.

CONCLUSION:

Our results showed that pretreatment serum level of OPN is significantly related to outcome in DLBCL patients. Ongoing extension study and additional follow-up will provide more information moving forward.

Disclosures:

No relevant conflicts of interest to declare.
Single Nucleotide Polymorphisms in ABCB1 and CBR1 Predict Toxicity to R-CHOP Type Regimens in Patients with Diffuse Non Hodgkin's Lymphoma
Authors: Jordheim Lars-Petter , Ribrag Vincent , Ghesquieres Herve , Pallardy Sophie , Delarue Richard , Tilly Herve , Haioun Corinne , Jardin Fabrice , Salles Gilles , Dumontet Charles
Published: October 2019

Abstract 1616

We analyzed single nucleotide polymorphisms (SNPs) in patients with diffuse large B-cell lymphoma treated in the prospective GELA LNH 2003 studies. Peripheral blood DNA samples collected at diagnosis before chemotherapy were obtained from 760 patients (among a total of 1367 accrued) including 441 randomized to received R-CHOP or modified R-CHOP (LNH 03–7B) and 319 who received R-ACVBP. The median age was 59 years (range 18–93) and there were 441 males and 319 females. 429 were IPI 0–2 (56.4%) and 331 were IPI 3–5 (43.6%). 119 patients had an ECOG performance status >1 (15.7%). B symptoms were present in 261 cases (34.4%). Serum albumin was below 35 g/L in 190 patients (27.7%). 489 patients (66.9%) had complete or unconfirmed complete response after induction therapy and 167 (22%) had partial response. At 5 years the overall survival was 73.9% (95% C.I. 69.7–77.6) and the progression free survival was 64.4% (95% CI 60.1–68.4). A total of 17 SNPs in 13 genes involved in drug metabolism or apopotosis were genotyped by TaqMan SNP Genotyping Assays (Applied Biosystems) on a LC480 (Roche) and correlated with toxicity occurring during treatment. Toxicity was evaluated prospectively using the NCI CTC V3 scale and associations were determined between specific genotypes and grade 3 or 4 toxicities. The studied genes were ABCB1, CAT, CBR1, FGFR4, IL10, NRG1, SLC22A16, SOD2, UGT1A1, CYP3A4, GSTP1, GSTM1 and GSTT1. Among these, 4 SNPs located in ABCB1 and CBR1 were found to be significantly associated with treatment-induced toxicity. The two SNPs localized in the ABCB1 gene were rs2032582 which was correlated with thrombocytopenia (p=0.04) and rs2229109 which was correlated with vomiting (p=0.003) and diarrhoea (p=0.007). The two SNPs localized in the CBR1 gene were rs20572 and rs9024 which were both correlated with anemia, thrombocytopenia and diarrhoea (p=0.02). ABCB1 codes for the drug efflux pump Pgp which has mainly been evaluated for its role in chemoresistance, is also known to be a key regulator of drug elimination and a determinant of pharmacokinetics. CBR1 codes for carbonyl reductase 1 which is involved in the first step of the metabolism of doxorubicin. These results suggest that genotyping of peripheral blood cells could help predict severe toxicity in patients receiving R-CHOP type regimens.

Disclosures:

Ribrag: Servier: Membership on an entity's Board of Directors or advisory committees, Research Funding; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Bayer: Research Funding; Sanofi-Aventis: Research Funding; Johnson & Johnson: Membership on an entity's Board of Directors or advisory committees.
The Internal Ribosome Entry Site-Medaited Expression of VEGF Rescues HS Sultan Tumor Cells From Mammalian Target of Rapamycin (mTOR)-Inhibitors Induced Apoptosis in Vivo
Authors: Frost Patrick , Gera Joseph , Lichtenstein Alan K.
Published: October 2019

Abstract 1659

An important molecular target of mTOR inhibitors in cancer therapy is VEGF expression and neo-angiogenesis. In prior studies, we demonstrated that, although rapalog mTOR inhibitors only induce G1 arrest in B-cell tumor lines, their administration in vivo in xenograft models resulted in tumor cell apoptosis that correlated with inhibition of neo-angiogenesis and VEGF expression within the tumor bed. Other in vitro studies have shown that IRES-dependent translation of myc and D-cyclins can provide a fail-safe mechanism for expression when mTOR inhibitors prevent cap-dependent translation and may act as a resistance mechanism to induction of G1 arrest in vitro. We, thus, tested if VEGF IRES activity could likewise regulate induction of anti-tumor effects and apoptosis in vivo. To test if VEGF IRES activity can regulate anti-tumor responses in vivo, we utilized the HS-Sultan B cell lymphoma line that is PTEN null. Its heightened AKT activity disarms the VEGF IRES, preventing this fail-safe mechanism and sensitizing to mTOR inhibitors. We ectopically expressed a version of the VEGF ORF in these cells fused to the p27 IRES (p27-VEGF), an IRES which is insensitive to AKT and effective in PTEN-null tumors. p27-VEGF transfected tumor cells were used as subcutaneous challenges in immunodeficient mice and results of mTOR inhibitor treatment compared to control mice challenged with tumor cells transfected with the VEGF ORF but without an AKT-resistant IRES. The anti-tumor responses were enumerated by assessing tumor size and tumor apoptosis, neo-angiogenesis and VEGF expression assessed by immunohistochemistry, ELISA, and Western blot analysis of tumor lysate. Ectopic expression of VEGF fused to the p27 IRES specifically enhanced VEGF expression and neo-angiogenesis in tumors of mice treated with the rapalog temsirolimus or active site mTOR inhibitor pp242 and significantly reduced tumor cell apoptosis and anti-tumor responses. The results confirm the critical role of VEGF expression in tumors during treatment with mTOR inhibitors and, furthermore, underscore the importance of IRES activity as a resistance mechanism to such targeted therapy.

Disclosures:

No relevant conflicts of interest to declare.
PRKD2 Serine-Threonine Kinase, an Essential Effector of Gabp Transcription Factor, Is Required for Development of Chronic Myelogenous Leukemia
Authors: Yang Zhong-Fa , Zhang Haojian , Ma Leyuan , Peng Cong , Chen Yaoyu , Green Michael , Li Shaoguang , Rosmarin Alan G.
Published: October 2019

Abstract 1672

Chronic Myelogenous Leukemia (CML) is a myeloproliferative neoplasm (MPN) caused by transformation of hematopoietic stem cells (HSCs) by the BCR-ABL oncogene. CML is associated with excessive proliferation of HSCs and massive expansion of the myeloid cell pool. GABP is an ets-related transcription factor that controls critical genes in myeloid and lymphoid development, and has been implicated in control of HSC growth. GABP is an obligate multimeric transcription factor that includes the DNA-binding ets component, GABPα, along with various GABPβ partner proteins. We conditionally deleted Gabpa in mouse bone marrow and found that Gabpa cells have a profound growth disadvantage due to cell cycle arrest in HSCs. In a mouse model of CML, animals transplanted with BCR-ABL-infected bone marrow developed massive myeloid cell expansion and died with a MPN. Induced deletion of Gabpa prevented development of CML, yet mice continued to produce mature BCR-ABL-expressing granulocytes for months without apparent illness. BCR-ABL+ cells were transplantable into secondary recipients without development of CML, and contributed to all hematopoietic lineages, thereby confirming expression of BCR-ABL by long-term HSCs. We used a bioinformatic approach to analyze GABP-bound genes that are upregulated in both human and mouse LSCs compared to normal HSCs. Among 115 GABP-bound, CML-associated genes, we identified Protein Kinase D2 (PRKD2) as a candidate effector of GABP. PRKD2 is a diacyl glycerol- and Protein Kinase C-activated serine-threonine kinase that has been implicated in cancer, but has not previously been associated with HSC functions or CML. Deletion of Gabpa markedly reduced PRKD2 expression in normal HSCs and progenitor cells. In vitro growth of BCR-ABL+ bone marrow cells was prevented by Gabpa deletion, but growth was partially rescued by forced expression of PRKD2. Knockdown and pharmacologic inhibition of PRKD2 blocked cell cycle entry of BCR-ABL+ cells. We conclude that Gabp is required for HSC cell cycle entry and for development of CML, and that these effects of GABP are mediated, in part, by PRKD2. These findings suggest that PRKD2 kinase may serve as a novel therapeutic target in leukemia.

Disclosures:

No relevant conflicts of interest to declare.
Outcomes of Patients (pts) with Myelodysplatic Syndrome (MDS) and Chronic Myelomonocytic Leukemia (CMML) Post Clofarabine Failure
Authors: Ghanem Hady , Manero Guillermo Garcia , Faderl Stefan , Takahashi Koichi , Ravandi Farhad , Cortes Jorge E. , O'Brien Susan , Daver Naval G. , Katragadda Lakshmikanth , Pemmaraju Naveen , Pierce Sherry A. , Quintás-Cardama Alfonso , Kadia Tapan M. , Kantarjian Hagop M. , Jabbour Elias J.
Published: October 2019

Abstract 1722

Introduction:

Clofarabine is a nucleoside analogue that has shown activity in pts with myeloid disorders. The outcome of pts with MDS and CMML post clofarabine is unknown.

Aims:

To evaluate the outcome of pts with MDS or CMML treated and failed clofarabine based chemotherapy as a first line or salvage regimen.

Methods:

We reviewed data of 89 pts with MDS and 21 patients with CMML treated with a clofarabine based chemotherapy at MDACC between 6/2001 and 5/2012. Thirty-nine pts (36%) received clofarabine as first line therapy and 71 pts (64%) received clofarabine as salvage therapy. Ninety-six pts (87%) received single agent clofarabine and 14 pts (13%) received a clofarabine containing combination. Response assessment followed standard criteria. Overall survival (OS) was measured from the time of therapy till the time of death or last follow-up.

Results:

One hundred and ten pts with a median age of 68 years (range, 42–88) were assessed. Sixty-five percent of the pts were older than 65 years. At the time of MDS diagnosis, 68 (61%) had a high or intermediate-2 risk International Prognostic System Score (IPSS). Thirty-one pts (27%) had complex cytogenetics. Sixty-one pts (55%) had failed therapy with a hypomethylating agent (HMA) before initiation of a clofarabine containing salvage therapy. Of the pts who received frontline clofarabine treatment, 15 (23%) achieved complete remission (CR) and 2 (3%) CR with incomplete platelet recovery (CRp), for an overall response rate (ORR) of 26%. Of the pts who received salvage clofarabine treatment, 4 (9%) achieved CR and 5 (11%) CRp, for an ORR of 20%. The median duration of response to clofarabine was 6 months. ORR was 14% among the 61 patients who had received a prior HMA. At time of clofarabine failure, 20 (18%) had progressed to acute myelogenous leukemia (AML). Fifty-eight patients received salvage therapy after clofarabine failure. Among these, 13 patients received allogeneic stem cell transplant, 17 patients received a high dose Ara-C containing regimen and 25 patients received only investigational treatments. Only 8 (14%) responded (median duration of response not reached) (range, 0–40 months). Within a median follow-up of 3 months from clofarabine failure, 13 pts (14%) remained alive. The median OS post clofarabine failure was 5.1 months and the 1-year survival rate of 25% (figure 1).

Conclusion:

Outcome of patients with MDS post clofarabine failure is poor, with a median survival of 5.1 months. These patients should be offered investigational strategies.

Disclosures:

Off Label Use: Use of clofarabine is investigational in MDS.
46/1 Haplotype Permits to Follow JAK2 Homologous Recombination: Modeling JAK2V617F clonal Architecture in PV Patients
Authors: Hasan Salma , Le Couedic Jean Pierre , Favale Fabrizia , Monte-Mor Barbara , Lacout Catherine , Casadevall Nicole , Solary Eric , Villeval Jean-Luc , Plo Isabelle , Vainchenker William
Published: October 2019

Abstract 1757

Myeloproliferative neoplasms (MPNs) are clonal hematopoietic stem cell (HSC) disorders characterized by excess proliferation of one or several myeloid lineages. More than 95% polycythemia vera (PV) and 50–60% essential thrombocythemia (ET) and primary myelofibrosis (PMF) patients harbor a somatic 1849 G>T mutation in JAK2 gene. Moreover about 30% of PV patients are homozygous for this mutation due to a loss of heterozygosity after a mitotic homologous recombination (HR). Among 92 haplotypes of chromosome 9p, 46/1 haplotype is strongly associated with the cis-aquisition of JAK2V617F mutation. The purpose of this study was to estimate the clonal frequency of WT, JAK2V617F/+ and JAK2V617F/V617F in progenitors compartments. Here, we have modeled the JAK2V617F clonal architecture in 9 PV patients heterozygous for the 46/1 haplotype by using the level of JAK2 and the 46/1 haplotype as a marker to follow HR. First we measured the global JAK2V617F and 46/1 allele burden in CD34+ cells either by allele-specific PCR or by Ion Torrent sequencing in order to calculate the expected WT, JAK2V617F/+ and JAK2V617F/V617F clones. Next, we compared the results with the experimental clonal frequency of WT, JAK2V617F/+ and JAK2V617F/V617F cells in individual colonies derived from the CD34+CD38+ compartment. In majority of patients, the observed values corresponded to the expected values suggesting that JAK2 46/1 haplotype can be used to estimate JAK2V617F clonal structure in PV patients. In three JAK2 46/1 heterozygous hemochromatosis patients used as controls, no JAK2 46/1 homozygous clone was observed showing that 46/1 haplotype itself was not responsible for HR. Furthermore, we have studied the proliferative advantage of the mutated clones in patients. No proliferative advantage of JAK2V617F clone has been observed in between CD34+CD38− and CD34+CD38+ progenitors stages whereas strong amplification of JAK2V617F clone was found in terminally differentiated polynuclear neutrophils (PNN). Moreover, during evolution of MPN in one patient, we observed an amplification of the JAK2V617F/V617F clone in both the CD34+CD38− and CD34+CD38+cell compartments suggesting acquisition of a proliferative advantage of the homozygous clone over time.

This simple modeling could help to understand the effect of treatments on the JAK2V617F clonal structure without working at the unicellular level.

Disclosures:

No relevant conflicts of interest to declare.
The Role of 14-3-3ζ in Regulation of Proteasome Inhibitor Bortezomib Sensitivity in Multiple Myeloma
Authors: Gu Yanyan , Kaufman Jonathan L. , Boise Lawrence H. , Lonial Sagar
Published: October 2019

Abstract 1845

The 14-3-3 proteins are a highly conserved protein family which includes β, γ, ε, η, σ, τ and ζ isoforms in mammalian cells. Through interacting with a number of protein clients, such as Cdc25, Bad, Raf1, and Foxo, 14-3-3 proteins act as integrators of diverse cell signaling pathways and participate in metabolism, cell cycle regulation, survival and apoptosis. We have previously demonstrated that expression of 14-3-3ζ is increased in the transition from MGUS to multiple myeloma (MM), and among all MM subsets, is expressed highest in the high risk genetic subsets [Gu et al. Blood (ASH Annual Meeting Abstracts), Nov 2011; 118: 1369]

Using our 14-3-3ζ knockdown and overexpression stable MM cell lines, we found 14-3-3ζ played important roles in MM cell proliferation and growth. We also found that silencing 14-3-3 appeared to impair bortezomib-induced cell apoptosis in LP1 cells as well as to another proteasome inhibitor MG132. To further explore the function of 14-3-3ζ in MM cell biology, we performed co-immunoprecipitation followed by mass spectrometry to identify the potential 14-3-3ζ binding partners in the LP1 14-3-3ζ overexpressed cell lines. Analysis using IPA (Ingenuity Pathway Analysis) revealed critical functions and pathways related to EIF2, eIF4, p70S6K and mTOR signaling, protein ubiquitination pathway and aminoacyl-tRNA biosynthesis. Among all the identified binding candidates, we also found proteasome subunits, which could explain the impact of overexpression on sensitivity to bortezomib.

To verify whether 14-3-3ζ can directly interact with the proteasome, we performed a His pull down assay using purified His-14-3-3ζ and LP1 cell lysate. We found that 14-3-3ζ can bind the 11S proteasome activator, PA28α. Using our LP1 14-3-3ζ overexpression stable cell line, we also confirmed the interaction between 14-3-3ζ and PA28α. Further experiments using native gel electrophoresis and western blot revealed more proteasome complexes formation in LP1 14-3-3ζ knockdown cells, suggesting 14-3-3ζ may regulate the function of proteasome through modulating proteasome assembly.

In summary, 14-3-3ζ expression appeared to be critical for MM cell proliferation, and may influence sensitivity to proteasome inhibition by its interaction with proteasome subunits. Our data provides invaluable information on the molecular mechanism of resistance to proteasome inhibitor in MM and also helps to develop new strategies to overcome proteasome resistance. Given the importance of 14-3-3ζ overexpression among the high risk cohort of MM patients, 14-3-3ζ represents an important therapeutic target in high risk MM.

Disclosures:

Kaufman: Millenium: Consultancy; Celgene: Consultancy; Novartis: Consultancy; Onyx: Consultancy. Lonial:Millennium: Consultancy; Celgene: Consultancy; Onyx: Consultancy; Merck: Consultancy; Novartis: Consultancy; BMS: Consultancy.
Pim1 Serine/Threonine Kinase Regulates the Number and Functions of Murine Hematopoietic Stem Cells.
Authors: An Ningfei , Lin Yingwei , Mahajan Sandeep , Wang Yong , Kraft Andrew , Kang Yubin
Published: October 2019

Abstract 2303

Background:

The genes and pathways that govern the functions and expansion of hematopoietic stem cells (HSC) remain to be elucidated. Pim (proviral insertion in murine lymphomas) protein kinases are a small family of constitutively active, highly conserved oncogenic serine/threonine kinases and have 3 members: Pim1, Pim2, and Pim3. Currently, little is known about the contribution of each Pim kinase in hematopoiesis. Pim1 was recently found to be important in the regulation of CXCR4 expression in HSCs (Grundler R et al, J. Exp Med 2009, 206:1957). However, the roles of Pim1 in HSC proliferation, self-renewal, and long-term repopulation are unclear. In the current study, we performed detailed hematological and bone marrow transplant studies to address these questions.

Methods:

We generated Pim1 transgenic (Tx) mice bearing human PIM1 under the control of vav hematopoietic promoter (vav-hPIM1 Tx). Pim1−/−, Pim2−/−, Pim3−/− single knockout (KO) mice were also utilized. We quantified the number of hematopoietic stem/progenitor cells (HSPCs) in these mice using flow cytometry, colony forming units (CFUs) and cobblestone area forming cell colonies (CAFCs) assays. In vivo BrdU labeling was performed to determine the proliferation status of long-term HSCs in these mice. CXCR4 expression and the homing of HSCs to bone marrow and spleen were also analyzed. Additionally, we performed noncompetitive, competitive, and serial transplantation assays to examine the role of Pim1, Pim2 and Pim3 in hematological reconstitution in lethally irradiated recipient mice. Finally, a limiting dilution competitive bone marrow transplantation assay using purified long-term HSC cells (Lin− Sca-1+c-kit+ CD34−) was performed to calculate the frequency of active HSCs in vav-hPIM1 Tx and Pim1−/−mice.

Results:

Conclusion:

Our current studies demonstrate a novel role of Pim1 serine/threonine kinase in the regulation of self-renewal, proliferation, and long-term repopulation of HSCs. The functions of Pim1 in hematopoiesis do not overlap with Pim2 or Pim3.

Acknowledgment:

We thank Richard Peppler at the Hollings Cancer Center Flow Cytometry Core for performing flow cytometry analysis. This work is supported by MUSC Hollings Cancer Center Startup Fund, Hollings Cancer Center ACS IRG, ASCO Conquer Cancer Foundation Career Development Award, NIH 1K08HL 103780–01A1, and NIH 3P30CA138313–01S3.

Disclosures:

No relevant conflicts of interest to declare.
Gonadal Function in Survivors After Hodgkin Lymphoma (HL) Treatment within the German Hodgkin Study Group (GHSG) HD13–15 Trials.
Authors: Behringer Karolin , Mueller Horst , Goergen Helen , Thielen Indra , Eibl Angelika , Stumpf Volker , Wessels Carsten , Wiehlpuetz Martin , Rosenbrock Johannes , Halbsguth Teresa , Reiners Katrin S. , Schober Thomas , Renno Joerg H , von Wolff Michael , van der Ven Katrin , Kuehr Marietta , Fuchs Michael , Diehl Volker , Engert Andreas , Borchmann Peter
Published: October 2019

Abstract 2636

Purpose:

To improve fertility advice in HL patients before treatment and counseling during survivorship, detailed information on the impact of chemotherapy is needed. Therefore, we analyzed gonadal function in survivors after treatment of early favorable, early unfavorable and advanced stage HL.

Methods:

Women <40 years and men <50 years at diagnosis in ongoing remission at least one year after treatment within the GHSG HD13–15 trials were included. Hormone parameters, menstrual cycle, symptoms of hypogonadism, measures to preserve fertility, pregnancies, and offspring were evaluated.

Results:

A total of 1,323 (55%) of 2,412 contacted female and male survivors were evaluable for the current analysis. In women and men, mean age at fertility assessment was 32 and 38 years and mean observation time from the end of treatment was 46 and 48 months, respectively. Comparison of the participating and non-participating patients qualifying for our analysis showed no relevant differences. Hormone levels correlated significantly with therapy intensity (p<.001). After 6–8 cycles BEACOPP (bleomycin, etoposide, adriamycin, cyclophosphamide, vincristine, procarbazine, prednisone), mean Anti-Muellerian hormone (AMH) levels in females were 0μg/l and 88.8% of males had Follicle-stimulating hormone (FSH) and inhibin B levels corresponding to oligospermia. Furthermore, low birth rates were observed in survivors after advanced-stage treatment within the observation time (women: 6.5%, men: 3.3%). Regular menstrual cycle was reported by >90% of early-stage HL female survivors and time to resumption of menstrual activity was mostly reached within one year. After advanced-stage treatment, menstrual activity was strongly related to age. 82% of women younger than 30 years had a regular cycle, compared to only 45% in the older age group (p<.001) and time to recovery was considerably longer than in early-stage patients. 34% of women >30 years suffered severe menopausal symptoms (3–4 fold more frequently than expected). In contrast, male survivors had mean levels of testosterone within the normal range and reported no increased symptoms of hypogonadism.

Conclusions:

The present analysis in a large group of female and male HL survivors provides well-grounded information on gonadal toxicity of the currently used treatment regimens. Accordingly, the results allow a risk adapted planning of fertility preservation before therapy and a comprehensive support during survivorship.

Disclosures:

No relevant conflicts of interest to declare.
Genetic or Pharmacological Reductions in DNA Methylation Selectively Inhibit Peripheral T-Cell Lymphomagenesis.
Authors: Trowbridge Jennifer J. , Li Mingjie , Roberts Charles W.M. , Orkin Stuart H.
Published: October 2019

Abstract 2760

The significance of mutations in components of the DNA methylation machinery in blood cancer has become a topic of intense investigation. Unlike genetic modifications, the reversible nature of DNA methylation and other epigenetic changes makes them attractive therapeutic targets. Very recently, mutations in the DNA methyltransferase DNMT3A and the DNA demethylase TET2 were identified in human peripheral T cell lymphoma (PTCL) [1]. These findings provided a novel link between the development and progression of PTCL with deregulation of DNA methylation processes. Importantly, this finding also extended the few known mutations associated with both T-cell lymphoma and myeloid leukemia. Our previous work identified acute sensitivity of MLL-AF9–induced myeloid leukemia (AML) to DNA demethylation through loss or haploinsufficiency of the DNA methyltransferase Dnmt1 [2]. Here, we investigated the sensitivity of PTCL to DNA demethylation. Lymphoma was induced in mice by inactivation of Snf5, a core subunit of the SWI/SNF chromatin remodeling complex, driven by CD4Cre (CD4Cre-Snf52lox). Inactivation of Snf5 leads to rapid onset of mature CD8+ PTCL with a median survival of 10 weeks of age. Strikingly, loss of Dnmt1 in this model (CD4Cre-Snf52lox-Dnmt12lox) completely abrogated development of lymphoma. Furthermore, haploinsufficiency of Dnmt1 was sufficient to increase event-free survival to 13 weeks of age (p=0.0008). Loss or haploinsufficiency of Dnmt1 did not impact normal T cell development in the thymus with the exception of a modest reduction in CD8+ CD44hi memory T cells. Based on the selective response of PTCL to reduced levels of Dnmt1 and DNA methylation, we screened a panel of pharmacological DNA demethylating agents for efficacy in PTCL. We found three putative DNA methylation inhibitors; the nucleoside inhibitor zebularine and non-nucleoside inhibitors RG108 and procainamide, which inhibited proliferation of primary murine PTCL in vitro. These inhibitors were effective at doses that did not restrict the proliferation of normal CD8+ T cells. When these inhibitors were evaluated for efficacy in vivo, both zebularine and procainamide were found to inhibit growth of primary murine PTCL. Together, these results suggest that therapy of PTCL with DNA methylation inhibitors or other DNA demethylating agents may achieve a favorable therapeutic index. Further, these results support the concept of a shared competitive advantage of myeloid leukemia and T-cell lymphoma in carrying mutations in the DNA methylation machinery. [1] Couronne L et al., NEJM, 2012, 366:95-6; [2] Trowbridge et al., Genes Dev, 2012, 26:344-9.

Disclosures:

No relevant conflicts of interest to declare.
Higher Than Expected Incidence of Chronic Myeloid Leukemia in Solid Organ Transplant Recipients.
Authors: Dhanarajan Asha R. , Hsu Jack W , Wingard John R. , Chang Myron N , Soldevila-Pico Consuela , Rehman Shehzad , Baz Maher , Norkin Maxim
Published: October 2019

Abstract 2799

Background:

Chronic immunosuppression, a known risk factor for many malignancies, has not been identified as a risk factor for chronic myeloid leukemia (CML). Here we report higher than expected incidence of CML in organ transplant recipients observed at a single institution over a 12 year period.

Methods:

We report all cases of CML diagnosed in adult solid organ transplant recipients at a single institution from 2000–2011. These organ transplant patients were followed at our institution for their transplant related care, which enabled a detailed review of the cases of CML. The observed incidence of CML cases during the 12 year period was compared to the published national CML incidence in the general adult population by the exact binomial test.

Results:

As reported to the Organ Procurement and Transplant Network, our institution performed 3,223 adult solid organ transplants from 2000–2011. Four of these organ transplant recipients developed CML at various intervals post-transplant (Table 1). All patients had CML diagnosed in chronic phase after the evaluation of abnormal leukocytosis and splenomegaly. No additional cytogenetic abnormalities besides Philadelphia chromosome t(9;22) were observed in any of these patients. All patients were treated with imatinib and achieved a complete cytogenetic response (CCyR) within 12 months of therapy. Two patients subsequently achieved complete molecular response, one patient remained in CCyR on imatinib and one patient died from septic shock while in CCyR.

Conclusion:

The observed 12 year incidence of CML was 4 out of 3223 transplant recipients. This incidence significantly exceeds the reported national incidence of 1.6 cases per 100,000 persons per year (p = 0.004, exact binomial test). We hypothesize that the increase in CML incidence in solid organ transplant recipients results from chronic immunosuppression. We also observed that clinical presentation and response of CML to imatinib therapy in solid organ transplant recipients were similar to non-transplant CML patients.

Disclosures:

No relevant conflicts of interest to declare.
Decreased Levels of Total or HDL Cholesterol in Primary Myelofibrosis Are Associated with Shortened Survival: DIPSS-Plus Independent Prognostic Value.
Authors: Sulai Nanna , Mengistu Biruk , Gangat Naseema , Hanson Curtis A. , Ketterling Rhett P , Pardanani Animesh , Tefferi Ayalew
Published: October 2019

Abstract 2851

Background:

It is widely appreciated that total cholesterol (TC) and triglyceride (TG) levels are decreased in patients with primary myelofibrosis (PMF). However, a systematic study looking into the serum lipid profile in PMF and its phenotypic and prognostic relevance is lacking.

Methods:

An updated Mayo Clinic database of 1008 karyotypically- and DIPSS-plus-annotated patients with PMF was used to identify study patients in whom serum lipid and lipoprotein levels were available at time of referral. Overall (OS) and leukemia-free (LFS) survivals were calculated from the time of referral, which was also the time of serum lipid analysis.

Results:

A total of 207 patients met the above stipulated criteria and had measurement of TC (n=207), TG (n=204), HDL cholesterol (HDL-C) (n=187), LDL cholesterol (LDL-C) (n=176) and non-HDL cholesterol (N-HDL-C) (n=184). The corresponding median (range) values (mg/dL) were 132 (57–296), 147 (42–742), 31 (8–96), 67 (11–186) and 104 (7–249). TC was significantly (P<0.05) lower in the presence of male sex, older age, red cell transfusion need, hemoglobin <10 g/dL, marked splenomegaly, circulating blasts, constitutional symptoms, JAK2 V617F, and ASXL1 mutations. TG was significantly (p<0.05) lower in the presence of JAK2 V617F, red cell transfusion need, hemoglobin <10 g/dL and thrombocytosis. DIPSS-plus risk categories showed significant differences in their TC (p<0.0001), HDL-C (p=0.004), LDL-C (p=0.004), and N-HDL-C (p=0.009) profiles with higher levels seen in lower risk patients; there were no correlations with TG levels.

In univariate analysis, lower levels of TC, HDL-C, LDL-C and N-HDL-C were all associated with shortened survival (P<0.01 for each association) whereas survival was not affected by TG level (p=0.42). Multivariable analysis in the context of DIPSS-plus confirmed the independent prognostic relevance of both TC (p=0.05) and HDL-C (p=0.02) for OS. A similar analysis disclosed no correlation with LFS. Exclusion of patients receiving statin or other anti-lipid treatment did not affect the overall results. Patients in the lower quartiles for either TC (approximately <100 mg/dL) or HDL-C (approximately <25 mg/L) compared to those with higher levels displayed significantly shorter survival (Figure; RR 2.4, 95% CI 1.6–3.7; p<0.0001) that was not accounted for by DIPSS-plus (RR 1.6, 95% CI 1.1–2.5; p=0.03).

Conclusions:

Decreased levels of total or HDL cholesterol in PMF cluster with adverse disease features and carry a DIPSS-plus independent adverse prognostic value. Measurement of TC and HDL-C in PMF might be useful in monitoring disease progression and treatment response.

Disclosures:

No relevant conflicts of interest to declare.
The PI3K Inhibitor GDC-0941 Attenuates Disease in a KrasG12D Mouse Model of CMML and JMML.
Authors: Akutagawa Jon , Dail Monique , Friedman Lori S , Shannon Kevin M. , Sampath Deepak , Braun Benjamin S.
Published: October 2019

Abstract 2862

Chronic and juvenile myelomonocytic leukemias (CMML and JMML) are overlap myelodysplastic/myeloproliferative neoplasia (MDS/MPN) syndromes that respond poorly to conventional treatment regimens. Both diseases are characterized by aberrant N-Ras, K-Ras, Cbl, and SHP-2 proteins, which are not attractive drug target candidates. Focus has shifted to downstream effector pathways, which include Raf/MEK/ERK, phosphoinositide-3-OH kinase (PI3K)/Akt, and Ral-GDS/Ral-A cascades. However, it is unclear which pathways, if any, should be targeted. In part to address this question, we previously developed a mouse model of CMML and JMML by expressing a conditional “knock-in” KrasG12D oncogene in bone marrow. Our earlier studies showed that inhibition of MEK yields a significant reduction in disease burden in this model, including reduced leukocytosis, improved anemia and enhanced survival. Here, we interrogate the role of the PI3K/Akt pathway in KrasG12D driven MPN and further explore which specific pathways are responsible for leukemogenesis due to hyperactive Ras. We administered GDC-0941, a selective PI3K inhibitor, to Mx1-Cre, KrasG12D mutant mice Mice with well established MPN and wild-type (WT) littermates were randomly chosen to receive daily oral administration of GDC-0941 or a control vehicle. Treated mice exhibited dramatic corrections of leukocytosis and anemia as well as decrease in splenomegaly. Flow cytometry of bone marrow and peripheral populations also imply that GDC-0941 treatment corrects the aberrant proliferation, amends differentiation of bone marrow progenitors, and revives ineffective erythropoiesis found in KrasG12D mice. Treatment also resulted in markedly improved survival of KrasG12D mice; virtually all KrasG12Dmice in the treatment arm outlived their control counterparts. Our data suggest PI3K inhibition may play a role in suppressing hematologic dysfunction in JMML and CMML patients. Potential crosstalk between PI3K and MEK signaling further suggest that combinatorial activities of PI3K and MEK inhibition should be investigated.

Disclosures:

Friedman: Genentech, Inc.: Employment. Sampath:Genentech, Inc.: Employment.
Gene Expression Profiling (GEP) in MGUS and AMM: Predictors of Progression.
Authors: Waheed Sarah , Heuck Christoph , Qu Pingping , van Rhee Frits , Usmani Saad Z , Zhang Qing , Sexton Rachael , Crowley John , Epstein Joshua , Dhodapkar Madhav V. , Shaughnessy John D , Barlogie Bart
Published: October 2019

Abstract 2933

Monoclonal gammopathy of undetermined significance (MGUS), a premalignant plasma cell dyscrasia, is differentiated from asymptomatic multiple myeloma (AMM), based on the level of monoclonal immunoglobulin (M spike) and bone marrow plasma cell infiltration (M spike > 3 g/dl and/or marrow plasmacytosis >10% in AMM). MGUS progresses to active Multiple Myeloma (MM) at a rate of 1–2% per year, thus imparting an average risk of 25% of progression over a lifetime. No single clinical variable, imaging modality or molecular study has yet been identified to predict progression. As a part of SWOG observational trial S0120, 262 patients were enrolled at MIRT and their GEP of purified plasma cells (PC) prospectively obtained. Here we report the results of GEP as predictor of progression. Among those with baseline GEP data available, 127 were non-IgM, AMM or MGUS and were otherwise eligible for the study. Baseline samples were restricted to those samples taken no more than 6 months prior to or 14 days following registration to S0120. If a patient had multiple baseline samples, then the sample taken closest to the patient's registration date was used. GEP studies were performed to assign molecular classification and risk scores, along with GEP-derived amp1q21, delTP53, DKK1 and other variables. With a follow-up of 36 months in the subset with evaluable GEP baseline data in 40 MGUS and 87 AMM cases, GEP characteristics were compared with those of untreated MM patients treated with TT2, TT3, TT4, and TT5 protocols, in the context of normal donor PC signatures. Comparing MGUS with AMM, CD-2 molecular subgroup was over-represented in MGUS and HY in AMM. PSMD4 on chromosome 1q21 was also linked to AMM. In terms of GEP-70 risk model, 36% of AMM and 15% of MGUS had scores exceeding -0.26. Univariate predictors for treatment-requiring MM included the well-known serum-M and bone marrow PC variables, and GEP-70 score >-0.26 (HR=8.82, p<0.001). Whole bone marrow biopsy (BMB) GEP samples from MGUS/AMM were available in 26 samples. Applying a BMB-65 model distinguishing MM-BMB from NL-BMB (normal donors) and MGUS/AMM-BMB, we observed that there was a strong trend for delayed MM progression when MGUS/AMM-BMB scores were in the top tertile (most NL-like). Independent validation data will be presented.

Disclosures:

Dhodapkar: Celgene: Research Funding; KHK: Research Funding.
Granulocyte Colony-Stimulating Factor-Mediated Immunoregulation Via Inducing Blood Cells Expressing Human Leucocyte Antigen-G.
Authors: Liu Hui , Du Xuan , Chen Yinkui , Xuan Li , Wu Xiuli , Zhang Yu , Fan Zhiping , Huang Fen , Zhang Xian , Zhai Xiao , Zhang Fuhua , Sun Jing , Liu Qifa
Published: October 2019

Abstract 3051

Background

Peripheral blood stem cells (PBSCs) obtained from granulocyte colony-stimulating factor (G-CSF)-mobilized donors have been used more frequently than bone marrow stem cells as the source of cells in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Although G-CSF–mobilized PBSC grafts contain more mature T cells than bone marrow cell grafts, the incidence and severity of graft-versus-host disease (GVHD) were not elevated. G-CSF-induced immune tolerance might be via inducing T helper type 2 (Th2) polarization, the promotion of regulatory T cell and tolerogenic dendritic cell (DC) differentiation. However, these mechanisms are not fully understood. Human leucocyte antigen-G (HLA-G) is a tolerogenic molecule which participates in the regulation of immune response. In this study, to explore the mechanisms of G-CSF-induced immunoregulation, the effect of G-CSF on blood cells expressing HLA-G was studied.

Methods

Membrane-bound HLA-G (mHLA-G) was detected using flow cytometry analysis; soluble HLA-G (sHLA-G), interferon gamma (IFN-γ) and interleukin 10 (IL-10) were determined by enzyme-linked immunosorbent assay (ELISA); HLA-Gpos cells were isolated using flow cytometry, and mixed leukocytes reaction (MLR) was carried out to assess the suppressive effect of HLA-Gpos cells.

Results

CD3+CD4+ T cells, CD3+CD8+ T cells, CD19+ cells and CD14+ cells all expressed mHLA-G in peripheral blood (PB) and bone marrow (BM) from 18 healthy donors before and after G-CSF mobilization. The levels of sHLA-G and mHLA-G on these cells in PB and BM all increased significantly after G-CSF mobilization (all P<0.05). The levels of sHLA-G and mHLA-G on these cells in BM were all higher than that in PB, including before and after G-CSF mobilization (all P<0.05). Bone marrow mononuclear cells (BMMCs) were stimulated with G-CSF in vitro, and the levels of mHLA-G on these cells and sHLA-G in culture supernatant all increased significantly after BMMCs cultivated with G-CSF for 24 hours (all P<0.001). In addition, the levels of IFN-γ and IL-10 also elevated in culture supernatant (both P<0.05). Antibodies blocking experiments for IL-10 and IFN-γ showed that IL-10 and IFN-γ were not necessary for G-CSF-induced HLA-G expression of blood cells. The results of MLR showed that HLA-Gpos cells were able to suppress the proliferation of allogeneic lymphocytes.

Conclusion

G-CSF could directly induce blood cells expressing HLA-G, which might be another mechanism of G-CSF-mediated immunoregulation in G-CSF–mobilized PBSC transplants.

Disclosures:

No relevant conflicts of interest to declare.
Airway Dilation in Bronchiolitis Obliterans After Allogeneic Hematopoietic Stem Cell Transplantation.
Authors: Gazourian Lee , Coronata Anna Maria F , Rogers Angela J , Weinhouse Gerald L , Soiffer Robert J. , Antin Joseph H. , Ritz Jerome , Ho Vincent T , Baron Rebecca M , Washko George R
Published: October 2019

Abstract 3058

Rationale:

Bronchiolitis obliterans syndrome (BOS) is a late, non-infectious pulmonary complication following hematopoietic stem cell transplantation (HSCT). The prevalence is estimated to be between 5–10% after allogeneic HSCT with a significant increase in morbidity and mortality. We were interested in assessing quantitative radiologic characterization of airway remodeling in these subjects.

Objectives:

To examine quantitative measurements of airway morphology and their correlation with lung function in a cohort of patients who underwent HSCT and developed BOS.

Methods:

All patients who underwent an allogeneic HSCT at the Dana-Farber Cancer Institute/Brigham and Women's Hospital (n=1854) between January 1st 2000 and June 30th2010 were screened for the development of BOS using modified NIH diagnostic criteria. Clinically acquired high resolution CT (HRCT) scans of the chest were collected. Discrete measures of airway wall area were performed in a total of 16 manually selected airways in the right and left upper and lower lobes using Airway Inspector (www.airwayinspector.org). From these measures, the square root of wall area of a 10-mm luminal perimeter (Pi10) was calculated. Spearman correlation was used to assess the relationship between square root of wall area at Pi10 and pulmonary function measures. Paired t-test was used for within group comparisons. Analyses were performed with SAS v. 9.2.

Measurements and Main Results:

Within our cohort 89 cases of BOS were identified of which 37 patients had HRCT scans available for analysis. 33 patients had pulmonary function tests within 30 days of the HRCT (Table 1). Ten of the 37 BOS patients had a HRCT scan at or prior to transplantation and a HRCT scan available after the diagnosis of BOS. Square root of wall area at Pi10 correlated significantly with FEV1(r = 0.636, p<0.0001), RV/TLC (r = −0.736, p< 0.0001) (Fig. 1), and when adjusted for age, sex and total lung capacity, the correlations remained significant (p<0.0001). There was a significant decline in square root of wall area at Pi10 in BOS cases compared to pre-transplant CT scans (p<0.001) (Fig 2).

Conclusions:

On HRCT scan BOS is characterized by central airway dilation, the degree of which is correlated to decrements in lung function. Future studies will examine whether chest CT assessment of central airway dilation can be used as a sensitive and specific tool for diagnosis and staging of BOS.

Disclosures:

No relevant conflicts of interest to declare.
Influence of Micrornas Expression in Graft-Versus-Host Disease After Allogeneic Transplantation.
Authors: Koldehoff Michael , Maniera Christina , Steckel Nina , Elmaagacli Ahmet H. , Beelen Dietrich W.
Published: October 2019

Abstract 3062

Background:

MicroRNAs (miRNAs) are a family of 19–24 nucleotide noncoding RNAs, which affect the regulation of gene expression in eukaryotic cells by binding to a 3′-untranslated region which target messenger RNAs. MiRNAs play important roles in many cellular processes such as development, stem cell division, apoptosis and cancer. We profiled miRNAs expressed on patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT).

Methods:

Here we analyzed in a retrospective study 50 patients (pts) for miRNAs expression (miRNA-21; -128; -146; -155; and -181) in whole blood that underwent allogeneic HSCT and analyzed their outcome. MiRNA expressions were performed by miRNA-specific real time RT-PCR.

Results:

In this cohort 15 pts received grafts from HLA-identical siblings (30%), 25 pts from matched (50%) and 10 pts from mismatched (20%) unrelated donors. Transplantat consisted of unmanipulated peripheral blood stem cells (n=41, 82%) or bone marrow (n=9, 18%). Of all pts, 12 (24%) had relapsed and 3 (6%) died of February 2012. There was no significant correlation between miRNA expressions from siblings and unrelated donors. For miRNA-21, we found a moderate down-regulation in mismatched unrelated donors (p<0.08) versus matched donors. Analysis of each miRNAs for relapse or TRM showed no statistically differences. Among these pts, 45 (90%) developed acute GVHD (18 pts had an acute GvHD of grade ≥2). There was a trend correlation between low level of miRNA-181 (327 ± 117% vs. 537 ± 575%; p<0.07) and miRNA-128 (158 ± 92% vs. 297 ± 485%, p<0.06) of pts with acute GvHD ≥ 2. In pts with severe acute GVHD (grade >3) comparing all other pts, we found significant reductions of miRNA-146 (355% vs. 1526%, p<0.0001), miRNA-21 (904% vs. 5526%, p<0.001) and miRNA-155 (5.66% vs. 3.52, p<0.04). However, no statistic differences were found in the miRNA expressions in regards to chronic GVHD.

Conclusions:

These results suggest that pts with low expression of miRNA-146, miRNA-21 and miRNA-155 confirms a relevant association of the development of acute GVHD and miRNA profilings could be an early indicator of severe acute GvHD.

Disclosures:

No relevant conflicts of interest to declare.