bluuebunny/crossref_metadata_2025 huggingface dataset:
Disruption of the SUMO Pathway in a High-Risk B-Cell Non-Hodgkin Lymphoma Pedigree
Authors: Garner Cassandra , Glenn Martha , Waller Rosalie G , Rajamanickam Venkatesh , Darlington Todd , Sargent Rob , Camp Nicola J
Published: October 2019

Taken together, B-cell lymphoproliferative disorders (lymphoma, multiple myeloma and leukemia) are the fourth most common form of cancer. Chronic Lymphocytic Leukemia (CLL), a specific sub-type of B-cell non-Hodgkin lymphoma (NHL), is the most common adult leukemia in Western countries. Despite its prevalence, the underlying genetic mechanisms responsible for CLL remain largely unknown. The strong familial clustering seen in CLL suggests that genetic variants contributing to its pathogenesis may be inherited. Our lab is dedicated to identifying inherited genetic risk variants associated with hematological malignancies with a specific focus on CLL. We hypothesize that there are multiple germline genetic variants (both common and rare) involved in risk of CLL. In order to identify rare variants, our lab uses the Utah Population Database (UPDB) to identify extended high-risk pedigrees with statistical excess of familial CLL. We then use next generation sequencing to identify genetic variants segregating in these high-risk pedigrees. This powerful study design for identifying rare variants and has previously been proven successful for identifying variants associated with other cancers.

We have performed whole-exome sequencing in one particularly high-risk pedigree containing 3 CLL cases and a mantle cell lymphoma case within 2 generations. We have identified variants in multiple genes associated with the SUMO pathway. We find rare variants in RANBP2, SP100, PML, IL1RL2 (paralog of IL1R) and CREBRF (transcriptional regulation through RNA pol II) that are shared by all NHL cases in this pedigree. Other genes in this pathway have been identified by previous CLL genome wide association studies, specifically FAS, TNF and SUMO1. Furthermore, a strong role has been previously suggested for the SUMO pathway in cancer cell survival and tumor progression, lending support to the potential role of this pathway in NHL risk. We are currently validating our sequence findings and determining the prevalence of these variants in other NHL cases included in the UPDB. Our high-risk pedigree findings are supportive that disruption of the SUMO pathway contributes to pathogenesis of NHL. Identification of the specific variants involved will increase our understanding of the molecular mechanisms contributing to NHL and has the potential to provide genetic markers that can be used for diagnosis and new avenues for treatment of these diseases.

Disclosures

No relevant conflicts of interest to declare.
CAR-T Cells Are Serial Killers of Tumor Cells
Authors: Jenkins Misty , Davenport Alex , Cross Ryan , Yong Carmen , Ritchie David S. , Trapani Joe , Kershaw Michael , Darcy Phil , Neeson Paul
Published: October 2019

Chimeric antigen receptor (CAR) T cells have shown clinical efficacy in refractory B cell malignancies. Despite these exciting clinical results, our fundamental understanding of CAR-T cell biology is limited, possibly limiting the broader application of CAR-T cells to additional haemopoetic and solid cancers. To date, the mechanism of CAR-T immunological synapse formation with tumor cells and kinetics of subsequent serial killing by CAR-T cells has not been explored. Here, we investigated the kinetics of CAR-T cell activation and cytotoxicity, including immune synapse formation, and kinetics of tumor cell killing, closely comparing to activation and cytotoxicity via the T cell receptor (TCR). To address this, we developed a mouse model in which the CD8+ T cells (termed CAR.OT-I cells) co-expressed two antigen receptors, the clonogenic OT-I TCR, and a second generation CAR comprising a scFV to human HER2, CD28 and CD3ζ signaling domains. Effector CAR.OT-I cells were activated via their antigen receptors using either SIINFEKL-pulsed or HER-2 expressing tumor cells, the interactions between the effector CAR.OT-I cells and tumor cells were then assessed by time lapse live microscopy. CAR.OT-I cell activation via the endogenous TCR or the CAR did not affect tumor killing kinetics, except the time taken from CAR.OT-I activation to detachment (from the dying tumor cell) was significantly slower when the endogenous TCR was engaged. Subsequently, we showed for the first time, that CAR.OT-I cells have serial killing capacity, which is important to consider when therapeutic numbers of CAR-T cells are likely to be outnumbered by tumor targets. Individual CAR.OT-I cells killed multiple tumor cells, whether activated via the endogenous TCR or the CAR. We further explored whether these findings have implications for killing of tumor cells using low effector:target cell ratio in short versus long-term killing assays, chromium release and xCELLigence killing assays respectively. We observed, no matter which antigen receptor was activated, the effector CAR.OT-I cells were equivalent killers of tumor cells in short term assays (4-8 hours). However, over a period of 50 hours, CAR.OT-I cells activated via the CAR killed tumor cells at a lower rate than when activated via the TCR. This was due to CAR.OT-I CAR expression down-regulation from 20-50 hours. This study highlights that fundamental differences occur in the way CAR-T cells kill tumor cells, depending on how the effector CAR-T cell is activated. Furthermore, the study provides important insights for CAR-T cell activation in vivo with implications for single- or dual-receptor-focused CAR-T cell therapy and improved clinical benefit.

Disclosures

No relevant conflicts of interest to declare.
Targeting IRAK1/IRAK4 Signaling in Waldenstrom's Macroglobulinemia
Authors: Yang Guang , Liu Xia , Chen Jie , Xu Lian , Tsakmaklis Nicholas , Chen Jiaji , Patterson Christopher J , Castillo Jorge J , Cohen Philip , Tan Li , Buhrlage Sara , Gray Nathanael , Treon Steven P
Published: October 2019

Background: MYD88 L265P somatic mutations are highly prevalent in Waldenström's macroglobulinemia (WM) (NEJM 367(9):826-33). MYD88 L265P activates multiple downstream signaling pathways including BTK and IRAK1/IRAK4 that support malignant cell growth and survival (Nature 470(7332):115-9; Blood 122(7):1222-32). Ibrutinib targets BTK, and shows high overall and major clinical response rates, though no complete responses are observed indicating alternative survival signaling.

Methodology: Phospho-flow analysis of IRAK1, IRAK4, and BTK was performed in primary WM cells taken from untreated WM patients, and those on ibrutinib therapy. IRAK1 or IRAK4 knockdown experiments were performed using lentiviral shRNA transduction. Immunoprecipitation, western blot and phospho-flow studies were used to detect protein expression and phosphorylation in WM cells. Cell survival following IRAK4 or IRAK1 knockdown, ibrutinib and/or IRAK4/IRAK1 inhibitor (EMD Millipore) treatment was assessed by Annexin V staining, AlamarBlue® Cell Viability Assay or CellTiter-Glo® Luminescent Cell Viability Assays.

Results: Phospho-flow analysis of bone marrow lymphoplasmacytic cells taken from WM patients following > 6 months of continued ibrutinib treatment demonstrated highly active IRAK1 and IRAK4, but not BTK. These findings prompted us to dissect the relative impact of IRAK1 and IRAK4 in supporting WM cell survival. Using lentiviral transduction, we identified shRNAs that produced similar levels of protein reduction by western blot analysis for both IRAK1 and IRAK4. Compared to scrambled control vector, knockdown of IRAK1 or IRAK4 both produced decreased tumor cell survival in MYD88 mutated BCWM.1 and MWCL-1 cells. More pronounced apoptosis, as well as sustained reduction in tumor cell growth occurred following knockdown of IRAK1 versus IRAK4. Treatment of primary WM cells taken from untreated patients, patients on ibrutinib therapy, as well as MYD88 mutated WM cells lines with ibrutinib and a toolbox IRAK4/IRAK1 inhibitor resulted in more robust reductions in NFkB signaling, and at least additive tumor cell killing versus either agent alone.

Conclusions: MYD88 L265P mutated WM cells show greater dependence on IRAK1 versus IRAK4 directed signaling. IRAK1/IRAK4 signaling may contribute to persistent WM cell survival following ibrutinib treatment. Combined BTK and IRAK inhibition leads to augmented blockade of NFKB signaling and enhanced WM cell killing. The studies provide a framework for the development and investigation of IRAK inhibitors, alone and in combination with ibrutinib in WM patients.

Disclosures

No relevant conflicts of interest to declare.
Pulmonary Complications in Patients Treated with Tyrosine Kinase Inhibitors, a Systematic Review and Meta-Analysis
Authors: Chai-Adisaksopha Chatree , Calvin Diep , Hillis Christopher M
Published: October 2019

Background: In patients with chronic myeloid leukemia (CML), long-term use of tyrosine kinase inhibitors (TKIs) is associated with hematological and non-hematological complications. To investigate the pulmonary complications (pulmonary edema and pulmonary arterial hypertension [PAH]) in CML patients receiving TKIs, we conducted a systematic review and meta-analysis of clinical trials and observational studies.

Methods: We searched MEDLINE, EMBASE and the Cochrane library to May 2015. The studies were included if they enrolled CML patients, used at least one of imatinib, nilotinib, dasatinib, bosutinib and ponatinib, and reported pulmonary effusion or PAH as one of their outcomes. We performed a single proportion meta-analysis for the cumulative incidence of each outcome. Subgroup analysis was carried out based on type of TKI, phase of disease, dosage and line of treatment.

Results: Thirty-nine studies, involving 6562 patients were included in the meta-analysis. The overall cumulative incidence of pleural effusion was 5% (95% confidence interval [CI]; 4.2-5.8, I2=95.9%). Subgroup analysis according to type of TKI revealed that dasatinib was associated with highest incidence of pleural effusion, 26.2% (95%CI; 21.4-31.1) compared to imatinib (0.5%), nilotinib (0.1%), bosutinib (2.1%) and ponatinib (0.3%), Figure 1. Subgroup analysis demonstrated that accelerated/blastic phase, non-first line treatment and higher dose of dasatinib were associated with a higher risk of pleural effusion. There were 7 cohorts reporting PAH. The overall cumulative incidence of pleural effusion was 0.2 per 100 patient year (95% CI; -0.3, I2 =0%) for all TKIs, Figure 2.

Conclusions: Pleural effusion is a frequently found pulmonary complication among CML patients receiving dasatinib. However, PAH is uncommon for TKI treated patients. We recommend a low threshold for performing a chest x-ray in symptomatic patients on dasatinib. Because of the low incidence of PAH, we cannot recommend routine screening for PAH in the absence of highly suspicious symptoms.

Figure 1. Cumulative incidence of pleural effusion in CML patients treated with tyrosine kinase inhibitors Figure 1. Cumulative incidence of pleural effusion in CML patients treated with tyrosine kinase inhibitors Figure 2. Cumulative incidence of pulmonary artery hypertension in CML patients treated with tyrosine kinase inhibitors Figure 2. Cumulative incidence of pulmonary artery hypertension in CML patients treated with tyrosine kinase inhibitors

Disclosures

No relevant conflicts of interest to declare.
Therapeutic Immune Monitoring of Chronic Myeloid Leukemia Patients Treated with Tyrosine Kinase Inhibitors: Focus on CD4+ CD25+ t Cells
Authors: Lu Ziyuan , Xu Na , Zhou Xuan , Gao Guanlun , Li Lin , Huang Jixian , Li Yuling , Lu Qisi , He Bolin , Pan Chengyun , Xiaoli Liu
Published: October 2019

Background and Objectives: In clinical, conventional Tyrosine Kinase Inhibitors (TKIs) including imatinib, dasatinib, and nilotinib are remarkably effective forms of therapy for certain types of solid cancers as well as Ph+ leukemias. In addition to the BCR-ABL target oncoprotein, they also inhibit certain off-target kinases (Eph, c-KIT, TEC, SRC). Some TKIs affect immune reconstitution as well as the proliferation, function, and activation of T cells. Certain TKIs have been known to have an especially strong effect on CD4+CD25+ T cells, also known as regulatory T Cells (Tregs). There is currently a gap in the clinical data available about on this area of study.

Patients and methods: In this study, we collected 108 Peripheral Blood (PB) samples from patients in the Chronic Phase (CP) of Chronic Myeloid Leukemia (CML) at the time of diagnosis (n=31) and also the TKIs treatment. Groups consisted of individuals treated with TKIs like imatinib (n=12), dasatinib (n=11) and nilotinib (n=8), as well as healthy controls (n=15). We evaluated the quantity and function of Tregs from patients in the CML-CP at the time of diagnosis and during treatment with TKIs.

Results: It was found that at diagnosis, patients with CML had a similar proportion and absolute number of lymphocytes compared to healthy donors. After TKIs treatment, proportions and absolute numbers of total T cellsACD4+ T cells and Tregs decreased at different degree. Moreover, thedecrease would be more and more significant as time goes on.Our results indicated that although these three TKIs show similar inhibitory effects in the proportion and number of Tregs in vivo, they have differential effects on the functions of Tregs in vitro. The proliferation, suppression, and expression of suppressive cytokines (IL-4,IL-10 and TGF-β) as well as suppression-associated molecules (FoxP3, GITR, and CTLA-4) of Tregs decreased in groups treated with imatinib and dasatinib. The decrease was not significant in the nilotinib-treated group.

Conclusions: The results showed that imatinib and dasatinib have stronger inhibitory roles than nilotinib when it comes to regulating the number and functions of Tregs. These findings can be used to argue in favor of calls for personalized treatment and follow-up of CML patients during TKIs treatment, particularly for those patients who received combination therapy with allo-transplantation and post-transplant TKIs.

Disclosures

No relevant conflicts of interest to declare.
Flow Cytometry Based Detection of MRD in Bone Marrow of Patients with Multiple Myeloma: A Comparison Between Fluorescent-Based Cytometry Versus Cytof
Authors: Ghosh Arnab , Carreau Nicole , Moscatello Alessandra , Rahman Adeeb , Qi Jingjing , Kim-Schulze Seunghee , Navada Shyamala C. , Chari Ajai , Cho Hearn Jay , Jagannath Sundar , Parekh Samir
Published: October 2019

The introduction of novel agents for the treatment of multiple myeloma (MM) has shifted the emphasis towards achieving a molecular complete remission (CR). Traditional methods to detect malignant plasma cells (PC) in minimal residual disease (MRD) utilize multicolor flow cytometry (MFC) to detect aberrant phenotypes. However fluorescent-based MFC assays are limited by the number of markers, difficulty in standardization of assays and overlap of signal between the fluorescent channels. These limitations can be overcome by cyTOF, a flow cytometry assay based on time-of-flight mass spectrometry using antibodies labeled with heavy-metal ions, permitting simultaneous assessment of large panels of markers. We have developed a novel highly sensitive mass cytometry protocol for the detection of MRD. BM from 5 MM patients and 1 non-myeloma control were RBC-lysed and labeled with MM markers for MFC and cyTOF. cyTOF is a flow cytometry based on mass spectometry where antibodies are labeled with heavy-metal ions, permitting utilization of more markers without concern for spillover. The MFC panel included CD38, CD138, CD45, CD56, CD19, CD117. Labeled cells for MFC were acquired by BD LSR Fortessa.. The panel for cyTOF comprised markers for cells across the hematopoietic spectrum and those specific for MM. Labeled cells acquired with cyTOF were analyzed using SPADE. Limits of detection (LOD) and quantification (LOQ) for MFC are based on prior reports. The results were compared with an independent commercial MFC-based assay (Genoptix). Malignant PC could be detected by MFC and cyTOF based assasys (See Figure). We were able to detect MRD in three subjects that had no detectable disease by an independent commercial MFC based assay (Genoptix). This can be attributed to acquiring at least 1x106 for our assays leading to a lower LOD and LOQ (greater sensitivity). Using cyTOF and SPADE, we could detect MRD in 4/5 patients. Overall our panel with cyTOF has a lower LOD than MFC for detection of MRD. Early detection of MRD in MM patients using a highly sensitive flow cytometry like cyTOF will help in risk stratification, predicting relapse and studying response to therapy.

Disclosures

Chari: Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium/Takeda: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; Array Biopharma: Consultancy, Other: Institutional Research Funding, Research Funding; Biotest: Other: Institutional Research Funding; Novartis: Consultancy, Research Funding. Jagannath:Bristol Myers Squibb: Honoraria; Janssen: Honoraria; Merck: Honoraria; Novartis: Honoraria; Celgene: Honoraria.
Factor XI Deficiency Protects Against Atherogenesis
Authors: Shnerb Reut , Harats Dror , Schiby Ginette , Gailiani David , Levkovitz Hanna , Tamarin Ilia , Shaish Aviv , Salomon Ophira
Published: October 2019

In industrialized societies atherosclerosis is still a major cause of morbidity and mortality, in spite of advances in development of cholesterol lowering drugs such as statins and ezetimibe. The detection of procoagulant proteases within atherosclerotic plaques, and the observation that patients with severe factor XI (FXI) deficiency have a reduced tendency to develop ischemic stroke, lead us to investigate whether absence of FXI would affect the process of atherogenesis. For this purpose, we created mice that are homozygous for null alleles for apolipoprotein E (apoE) and FXI (Double knock out [DKO] mice), and compared development of atherosclerosis in these animals to mice lacking apoE alone. At 24 weeks of age, there was a 32% reduction in atherosclerotic plaque area in the aortic sinus in apoE/FXI DKO mice compared to apoEKOmice (p=0.004). At age 42 weeks, apoE/FXI DKO mice had 25% smaller atherosclerotic plaque area in the aortic sinus compared to apoEKO mice (p=0.024), and aortic plaque area was reduced by 49% (p=0.028). Plasma cholesterol and triglycerides levels and lipoprotein profiles were similar in apoE/FXI DKO and apoE KO mice. In some murine infection models, FXI deficiency or FXI inhibition is associated with reduced markers of inflammation and improved survival. Based on this observation, we explored the possibility that reduced atherogenesis in apoE/FXI DKO mice is associated with reduced inflammation. There was a significant reduction in macrophages within atherosclerotic plaque in apoE/FXI DKO mice compared to apoE KO mice as determined by CD68 immunostaining. In conclusion, this work indicates for the first time that factor XI deficiency significantly reduces early, as well as advanced, atherosclerotic burden in an established animal model. We hypothesize that the effect of FXI on atherosclerosis is related to a proinflammatory effect within the atherosclerotic plaque. and propose that therapeutic targeting of FXI may have a role in preventing development of atherosclerosis. As FXI serves a minor role in hemostasis, treatment directed at this protein should not be associated with a high risk of major bleeding.

Disclosures

No relevant conflicts of interest to declare.
The ATP-Competitive mTOR Inhibitor AZD8055 Reduces Cell Proliferation and Tumour Load in Chronic Lymphocytic Leukaemia
Authors: Cosimo Emilio , Tarafdar Anuradha , Holroyd Ailsa , Dunn Karen , Catherwood Mark , Michie Alison M.
Published: October 2019

Chronic lymphocytic leukaemia (CLL), often diagnosed in the elderly, is incurable with current therapeutic regimes. Recent studies demonstrate that the microenvironment within CLL patient lymphoid organs protects leukaemic cells from chemotherapy induced apoptosis. This highlights the need for novel therapies that can overcome such cytoprotective signals. Serine/threonine protein kinase mammalian target for rapamycin (mTOR) is a key regulator of cell survival and proliferation and is commonly deregulated in cancer. mTOR is active in two complexes mTORC1 and mTORC2. We demonstrate that mTORC1 and mTORC2 substrates, including S6 (pS6S235/236) and Akt (pAktS473) respectively, are active although differentially regulated, in CLL cells from distinct prognostic subsets ex vivo, which suggests that mTOR may represent a valid therapeutic target for CLL. Initial studies with everolimus, an analogue of rapamycin, showed only limited antitumor activity in recurrent/refractory CLL patients, possibly because mTORC1 inhibition releases the "brake" that normally active mTORC1 has on mTORC2, thus enabling mTORC2 mediated signalling. To test the impact of inhibiting both mTORC1 and mTORC2 on cell proliferation and survival, we treated primary CLL cells and an aggressive CLL mouse model with the novel ATP-competitive mTOR inhibitor AZD8055 in vitro and in vivo. CLL proliferation and mTORC1/2 activity were significantly reduced upon addition of AZD8055 to NTL-CD154/IL4 co-cultures, which mimic pro-proliferative conditions present in the microenvironment of lymphoid organs. However, in the same conditions use of AZD8055 did not induce apoptosis at clinically-achievable drug concentrations (<150 nM), likely due to ineffective inhibition of Mcl-1 upregulation mediated by the NTL-CD154/IL4 co-cultures. In contrast, B cell receptor (BCR)-mediated survival was inhibited by AZD8055 treatment, inducing significant levels of apoptosis, concomitant with a decreased Mcl-1 expression. These findings suggest that the BCR and CD154/IL4 mediated pathways regulate Mcl-1 expression by distinct mechanisms. In vivo studies using the PKCa-KR-induced CLL mouse model revealed that AZD8055 treatment efficiently reduced tumour burden in the organs (spleen and bone marrow) and blood of mice with established CLL. This was reflected by in vitro studies showing that use of AZD8055 increased apoptosis and reduced proliferation in mouse CLL cells. Overall these data indicate that AZD8055 inhibits CLL proliferation, in vitro and in vivo, and disrupts BCR mediated survival, by downregulating Mcl-1 protein levels. Therefore dual mTOR inhibitors through reduction of tumour burden, show promise as a future therapy for CLL.

Disclosures

No relevant conflicts of interest to declare.
High Expression of AF1q Is an Adverse Prognostic Factor in Multiple Myeloma Patients Treated with Autologous Stem Cell Transplantation
Authors: Hagiwara Shotaro , Schiefer Ana-Iris , MINE Sohtaro , Kenner Lukas , Tse William
Published: October 2019

Introduction: Multiple myeloma is a heterogeneous hematological malignancy. Investigation on the poor prognostic factors contributes the development of the effective stratified treatment.

AF1q is an oncogene which expressed in leukemia cells, located in 1q21. The gene is well known as a one of the partner of 11q23. Recently, the association between the over expression of AF1q and the tumor progression has been reported by several investigators.

We studied the expression of AF1q in patients with multiple myeloma and analyzed the prognostic value.

Method: Newly diagnosed multiple myeloma patients in National Center for Global Health and Medicine hospital from January 2001 to March 2013 were studied. Patients were treated with vincristine-adriamycin-dexamethason or bortezomib-dexamethason induction therapy followed by autologous stem cell transplantation using high dose melphalan.

The expression of AF1q was evaluated using the immunostain of bone marrow clot samples at the diagnosis of multiple myeloma. The expression of AF1q was graded from "-" to "+++". The clinical response, progression free survival, and overall survival were analyzed.

Results: Clinical data and bone marrow clot samples of 61 patients were analyzed. Mean age was 55.5 years old, and 52.5% was male. The grades of AF1q expression were 2 of "-", 18 of "+", 17 of "++", and 24 of "+++". We defined the cases with "-" and "+" as low expression, "++" and "+++" as high expression. Very good partial response or better was obtained after completion of autologous stem cell transplantation in 45% of patients with low AF1q expression and 48.8% of high expression, there was no statistically significant difference.

Survival analysis using Log Rank method showed that high expression of AF1q was associated with significantly shorter progression free survival (p=0.004), but not overall survival.

Conclusion: In this study, we found that the high expression of AF1q was an adverse prognostic factor in multiple myeloma.

Figure 1. Figure 1.

Disclosures

Hagiwara: Celgene Corporation: Membership on an entity's Board of Directors or advisory committees.
Detection of Circulating Plasma Cells in Multiple Myeloma with Extramedullary Plasmacytoma
Authors: Wang Jing , Geng Shuang , Zhong Yuping , Chen Mingyi , Wang Wenming , Pang Yuhong , Zhang Jiajia , Liu Yuanyuan , Huang Yanyi , Jing Hongmei
Published: October 2019

Objective: To detect the circulating plasma cells (cPCs) in patients of multiple myeloma (MM) with or withoutextramedullary plasmacytoma (EMP).

Methods: The 21 patients of MM samples were collected from April 2014 to April 2015. There were 12 males, 9 females, with a median age of 60 (49 to 76 years old). Peripheral blood and bone marrow were examined before treatment or after EMP. Multi parameter flow cytometry (MFC) was used to analyze abnormal plasma cells (tumor cells) in samples of bone marrow and CD138 MACS positive sorting peripheral blood. The antibodies used in the flow cytometry were CD38-APC, CD138-PE, CD81-PE-Cy7, CD45-PacBlue, CD19-Percp-Cy5.5, CD56-mCherry-PE-ef610, CD117-AmCyan, CD16, Zombie-APC-Cy7.

Results: In these 21 patients, he ratio of sex is 1.33:1, the median age is 60 (49-76). The immunoglobin type is as follows: IgG κ 7 cases, IgG λ 5 cases, IgG 2 cases, IgA κ 3 cases, IgA λ 2 cases, λ light chain 1 cases. The morphology of bone marrow aspiration showed more than 15% plasma cells and abnormal plasma cells can be seen in bone marrow in cytometry. 9 of 21 patients diagnosed MM with EMP, 2 of them find EMP when initial diagnosis and 7 of them find EMP in the course of disease (6 months to 8 years). The sites of the EMP included head, jaw, chest wall, side of the rib, the soft tissue of the sacral region and the vertebral body and all patients had bone involvement. In 17 patients with complete clinical data, bone marrow and peripheral blood specimens, the cPCs negative rate was 87.5%(7/8) in EMP negative patients, while the cPCs positive rate was 66.7% (6/9) in EMP positive patients, the difference among groups was statistically significant (chi square values: 5.13, p = 0.024).

Conclusion: MFC has been widely used in diagnosis and minimal residual disease surveillance of MM, here we established the detection method of cPCs in MM patients, and it is valuable for clinical diagnosis and prognosis judgment.

Disclosures

No relevant conflicts of interest to declare.
The Majority of Myeloma Patients Are Vitamin D Deficient, Unrelated to Survival or Cytogenetics
Authors: Hudzik Samantha , Snoad Beau , Mousa Luay , Sborov Douglas W , Williams Nita , Jones Desiree , Hofmeister Craig C
Published: October 2019

Introduction: Since a link between solar radiation, vitamin D production, and decreased colon cancer mortality was established in 1980, there has been increasing interest in vitamin D and cancer, suggesting that higher vitamin D levels improve overall survival, specifically in breast and colorectal cancer (Maalmi H et al, Eur J Canc, May-2014, PMID 24582912), but also in follicular lymphoma (Kelly JL, J Clin Onc, 1-May-2015, PMID 25823738). In myeloma, largest published series is from the Mayo Clinic reporting on 148 newly diagnosed MM patients for which no survival association was found, but there were associations between low 25-OH-Vit D (<20 ng/mL) and higher serum CRP, serum creatinine, and ISS stage (Ng AC, Am J. Heme, Jul-2009, PMID 19415724); we wanted to expand on their trailblazing analysis. Cytogenetically high risk myeloma characterized by the amplification of 1q21 is associated with increased serum levels of soluble IL-6 receptor (sIL-6r) (Stephens OW, Blood, 2012, PMID 22072558) which may be associated with other markers of inflammation, e.g. CRP, creatinine, and b2microglobulin.

Methods: The Buckeye Myeloma Registry (OSU 10115) opened in 2011 to enroll any patient with a plasma cell dyscrasia. Serum total 25-OH-Vitamin D was measured at the time of the initial clinic visit to the myeloma group at Ohio State.

Results: Of a total of 843 patients, 115 (13.6%), 53 (6.3%) with SMM, and 675 (80.1%) with MM. In the 675 MM patients, the median age was 64 y.o. (range 28-95), 14.5% African-American and the remainder Caucasian, with 28.6% ISS stage 1, 48.7% ISS stage 2, 21.9% ISS stage 3, and 24.5% unknown. At diagnosis for the MM patients, 67% presented with lytic bone disease.

Out of 675 MM patients, there were 52 (7.7%) patients with < 10 ng/mL 25-OH-Vit D, 394 (51%) with low vit D (10-30 ng/mL), and 229 (39%) for 25-OH-Vit D 30-100 ng/mL. There was no correlation between 25-OH-Vit D and BMI or creatinine, but there was a strong correlation with race (r=0.18, p<0.000026).

Among the MM patients, log-rank [Mantel-Cox] analysis of overall survival with serum 25-OH-Vit D including all groups demonstrated no significant differences (p=0.9725) with only 101 events. There was no correlation between 25-OH-Vit D and the presence on CD138-selected FISH of 1q21 amplification (p=0.196), 17p (p53) deletion (p=0.68), or 13q deletion (p=0.812).

Conclusion: The majority of myeloma patients are vitamin D deficient, but this was not associated with worsened overall survival or with high risk cytogenetics. Cox proportional hazards analyses of survival adjusted for significant univariate covariates will be presented at the meeting. Correlations with presence or absence of diffuse lytic bone disease, severity of renal insufficiency, and race will also be presented at the meeting.

Disclosures

No relevant conflicts of interest to declare.
Re-Challenging with Anti-CD38 Monotherapy in Triple-Refractory Multiple Myeloma Patients Is a Feasible and Safe Approach
Authors: Lund Johan , Alici Evren , Chrobok Michael , Gruber Astrid , Ahmadi Tahamtan , Khan Imran , Nahi Hareth
Published: October 2019

Multiple Myeloma patients refractory to both proteasome inhibitors and immuno-modulatory drugs have poor prognoses, with median overall survival estimates of 9. We present data from two patients with MM in disease progression on ongoing treatment; both had received Daratumumab (Dara) as monotherapy earlier and were re-challenged with Dara on relapse.

Bone Marrow and blood samples were collected before start of treatment and the later before administration of each dose. Detailed analyses of circulating cell populations were performed.

We demonstrate that Dara had durable single-agent activity on re-treatment in both patients while both patients had no effective treatment options. As expected, we show that following initial Dara treatment, MM cells at relapse retained high levels of CD38 expression. Dara treatment depletes circulating NK cells almost immediately after the start of the treatment. Furthermore, both NK cells and CD8+ populations were partially increased at treatment interruption. Anti-inflammatory myelomonocytic cells showed a sharp decrease at the same time.

These data strongly suggest that continuous treatment with Dara decreases ADCC mediated antitumor activity using two independent mechanisms, which can both be recovered by a short treatment interruption. In line with this, maintenance treatment should include an intermittent treatment regime with appropriate time for recovery.

Figure 1. Figure 1.

Disclosures

Off Label Use: In this study Daratumumab was used in a compassionate use program provided by Janssen.. Ahmadi:Janssen: Employment. Khan:Janssen: Employment. Nahi:Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.
Clinical Analysis of Thromboembolism Associated with Lenalidomide-Based Regimens for Multiple Myeloma Patients
Authors: Qu Xiaoyan , Gu Yan , Li Jianyong , Chen Lijuan
Published: October 2019

Objective: To investigate and analyze the incidence, risk factors, prophylaxis and treatment of thromboembolism associated with lenalidomide-based regimens for multiple myeloma (MM) patients.

Methods: 22 newly diagnosed / relapsed MM patients received lenalidomide-based regimes from May 2013 to May 2015 in our department. All diagnosis of thromboembolism were based on objective clinical symptoms, and confirmed by imaging (lower extremity vascular ultrasound, chest CT angiography (CTA), and two-dimensional echocardiography). Investigatethe incidence of thethromboembolism, and analyze the prophylaxis and treatment for the thromboembolism according to risk factors such as patients' characteristics, disease status, and therapy regimes.

Results: Aspirin was used as thromboprophylaxis in 16 patients, low molecular weight heparin (LMWH) in 2 patients, and warfarin in 1 patient, while 3 patients received no thromboprophylaxis. There were 4 cases were diagnosedas thromboembolism with the incident of 18.2%. Threeof them were deep vein thrombosis (DVT), while 1 patient was combined withpulmonary embolism (PE), andthe rest one was found thromboembolism in the left atria. The chemotherapy regimes were lenalidomide plus dexamethasone (≤40mg qw). Other risk factors include: old age, male, immobility, central venous catheter (CVC), surgical history, hypertension, cardiovascularevent, IgG/IgA and light chain type, newly diagnosis, and erythropoietin (EPO). The management of thromboembolism included LMWH, warfarin, venous filter placement, adjustment of chemotherapy regimes and maintenance therapy of antithromboembolism. All the 4 patients were well managedat the last follow-up.

Conclusion: Thromboembolism was one of the most common non-hematologic adverse events of lenalidomide-based therapy. Aspirin was an effective option for thromboprophylaxis. More cases will be observed for longer time to optimize further evaluations forantithromboticprophylaxes, which include risk stratification-based prophylacticstrategies, new predictors and specific assessment of all thromboprophylaxis options.

Disclosures

No relevant conflicts of interest to declare.
Fetal Liver-Derived Stem Cells Ameliorate Immune Functions in Leptin Receptor-Deficient Mice
Authors: Li Ming , Adachi Yasushi , Ikehara Susumu
Published: October 2019

Fetal liver (FL) contains hepatic stem cells, hematopietic stem cells, and mesenchymal stem cells, as well as pluripotent stem cells and very small embryonic-like stem cells. FL has thus been available as a source of stem cells for regenerative medicine. Our previous report suggested that combining FL cell transplantation with the transplantation of fetal thymus prevented tumor growth in tumor-bearing mice. Moreover, in animal models, intra bone marrow-bone marrow transplantation (IBM-BMT) has proven to be the best approach for allogenic BMT. We here propose that transplanting FL cells by IBM-BMT can improve immune functions in leptin receptor-deficient (db/db) mice. FL cells were collected from FLs of C57BL/6 mice at 16 days post coitum, and then transplanted by IBM-BMT to leptin receptor deficent mice, an animal model of type 2 diabetes with obesity. Our results showed that the body weight was significantly lowered in the treated db/db mice than in the sham-treated db/db mice. The plasma IL-6 level significantly decreased and adiponectin level significantly increased after the transplantation of FL cells. Blood glucose levels also significantly decreased although not to within the normal range. This is the first report that the transplantation of FL cells may improve immune function, resulting in increased adiponectin levels, and decreased body weight in db/db mice.

Disclosures

No relevant conflicts of interest to declare.
Personalized Prophylaxis with Human-Cl Recombinant FVIII in HA Patients
Authors: Klamroth Robert , Lissitchkov Toshko , Rusen Luminita , Walter Olaf , Bichler Johann , Pasi K John , Tiede Andreas , Knaub Sigurd
Published: October 2019

Background

Prophylactic therapy aims to maintain sufficient factor VIII (FVIII) plasma levels to prevent bleeding. FVIII plasma trough level and time spent above a certain threshold are mainly determined by the half-life of the FVIII concentrate and the injection interval.

Aims

A clinical study was conducted to investigate the efficacy of individually PK-tailored prophylaxis with Human-cl rhFVIII.

Methods

This prospective, open-label, multicenter phase 3b study included previously treated immunocompetent adult patients with severe hemophilia A without past or present inhibitors. Each patient started with a PK evaluation (single dose of 60 ± 5 IU/kg) followed by 1-3 months of routine prophylaxis (i.e. 30-40 IU/kg every other day or 3 times per week, Phase I) until individual PK data was analyzed. It was calculated, which dose and injection interval would theoretically result in a trough FVIII level of ≥1%. Then, prophylaxis was continued for 6 months using the individually recommended treatment scheme (Phase II).

Results

The study enrolled 66 patents from 20 centers across 8 countries. The majority of patients (62.1%) had been treated on-demand only before study entry. Their median annualized bleeding rate (ABR) was 41. Key outcomes of the personalized prophylaxis are: The prophylactic injection interval was extended from usually 3 times per week in Phase-I to twice per week or less in 58% of patients.The median dosing interval was 3.5 days.73% of patients did not experience any bleeding episode.The mean ABR in phase-II was 1.45 (3.16 in Phase-I).The median weekly prophylactic dose decreased by nearly 10% compared to Phase-I.There were no inhibitors and related serious adverse events.

Conclusion

The data suggest that personalized prophylaxis with Human-cl rhFVIII results in a more convenient treatment for more than half of the patients with lower factor consumption and a lower ABR while remaining safe and efficacious.

Disclosures

Klamroth: Biogen and SOBI: Honoraria, Speakers Bureau; Bayer, Baxter, CSL Behring, Pfizer, Novo Nordisk, and Octapharma: Honoraria, Research Funding, Speakers Bureau. Rusen:Octapharma: Other: Investigator. Walter:Octapharma: Employment. Bichler:Octapharma AG: Employment. Pasi:Biogen, Octapharma, Genzyme, and Pfizer: Consultancy, Honoraria; Octapharma: Research Funding. Tiede:Octapharma: Other: Investigator, Speakers Bureau; Leo Pharma: Consultancy, Honoraria; SOBI: Consultancy, Honoraria; Boehringer Ingelheim: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Novo Nordisk: Consultancy, Honoraria, Research Funding; CSL Behring: Consultancy, Honoraria, Research Funding; Biogen Idec: Consultancy, Honoraria; Biotest: Consultancy, Honoraria, Research Funding; Bayer: Consultancy, Honoraria, Investigator, Research Funding; Baxter: Consultancy, Honoraria, Research Funding; Coachrom: Research Funding. Knaub:Octapharma: Employment.
Prolonged Survival in Philadelphia Positive Acute Lymphoblastic Leukemia Treated with Autologus Stem Cell Transplantation in the Inhibitor Tyrosine Kinase Era : A Retrospective Study
Authors: Favennec Camille , Chretien Marie-Lorraine , Legouge Caroline , Bastie Jean-Noel M. , Caillot Denis
Published: October 2019

With tyrosine kinase inhibitors (TKI) containing regimen and without allogenic stem cell transplantation (SCT), some studies showed prolonged survival in Philadelphia positive (Ph+) acute lymphoblastic leukemia (ALL), questioning the place of the allogenic SCT in the TKI era. We retrospectively reported the outcome of 39 patients with ALL Ph+ cured at the Bocage hospital, Dijon, France. The complete remission rate (CR) after induction was 100%, 1 patient died during consolidations. Two patients received an allogenic SCT and died of treatment related toxicity. Thirty six patients were referred to an autologus SCT strategy, in case of collection failure (7 patients) they received prolonged chemotherapy, for all TKI was given until progression or death. In this group the 5 years probability of overall survival and progression free survival are 60% and 53% respectively. Twenty two patients are alive in CR, 13 relapsed, 1 died in CR. Older age and high white blood count at diagnosis are bad prognostic factors. There were no correlation between minimal residual disease and prognosis. Our study showed prolonged survival is possible without allogenic SCT, in the TKI era. Autologus SCT is easily accessible and is associated with a very low mortality. These results should be confirmed by prospective studies including a larger number of patients.

Disclosures

No relevant conflicts of interest to declare.
Local Experience with Autologous Stem Cell Transplant in Multiple Myeloma at a Public Institution (Instituto Nacional de Cancerologia)
Authors: Cervera Eduardo , Torres Jorge Carlos , Zapata Nidia P. , Labardini Juan Rafael , Espinoza Jose Ramiro , Vieyra Magnolia , Sosa Antonio , Lozano Valentin , Candelaria Myrna , Meneses Abelardo
Published: October 2019

Introduction.

Autologous stem cell transplant is considered the standard of care in young (<70) fit patients with Multiple Myeloma. We know that intensive chemotherapy or stem cell transplant do not produce a cure, but it does prolong event free survival and overall survival.

The aim of this study is to report 15 years of experience in stem cell transplant at the Multiple Myeloma (MM) clinic at Instituto Nacional de Cancerologia (INCan).

This is a retrospective, observational trial, we reviewed clinical and electronic files of patients that received an autologous stem cell transplant between January 1st of 2005 and March 1 2015. We assessed clinical status, demographic variables, disease status and clinical outcome of the patients that were included in the study.

48 patients were included into the study, 25 males and 23 females, we grouped the patients according to age, <35 years (2 patients), <50 years (14 patients), 50-65 years (31 patients), >65 years (1 patient).

34 patients had a normal karyotype, 4 had 13q14, 2 had MLL deletion and 8 did not had a karyotype performed. According to the M component we had 6 IgA patients, 32 IgG, 1 IgM, 1 Kappa, 5 lambda, 2 non secretory and 1 combined.

According to ISS, 34 patients were assigned a ISS of 1, 10 a SS of 2, and 4 a ISS of 3. The majority of our patients were transplanted within the first line of treatment, 2 within the second line and none with more than 2 lines of treatment.

20 patients that received thalidomide plus dexamethasone achieved complete remission prior to transplant. 14 patients received thalidomide plus dexamethasone achieved very good partial response. 4 patients that received bortezomib plus thalidomide or dexamethasone achieved complete remission prior to transplant. 4 patients received bortezomib plus thalidomide or dexamethasone achieved very good partial response prior to transplant. 3 patients that received two lines of treatment achieved complete remission prior to transplant. 3 patients achieved very good partial response prior to transplant and received more than two lines of treatment.

Time from diagnosis to transplant had a mean time of 17.4 months, with 6-12 months as the most prevalent group with 20 patients, followed with 13 patients in the 12-24 months window. 17 tandem transplants were performed.

From the 25 patients that received a ASCT and were in CR, 19 maintained that response, from the 23 patients that achieved VGPR 20 maintained that response, 1 achieved partial response (PR), 4 had stable disease, and 4 had progression of the disease.

We are looking forward to presenting the full data of our analysis. Since our casuistry does not differ from the international reports.

Disclosures

No relevant conflicts of interest to declare.
Haploidentical Donor Transplantation Is Not Inferior to Identical Sibling Donor for Patients with Chronic Myeloid Leukemia in Blast Crisis
Authors: Ma Yanru , Xu Lanping , Huang Xiaojun
Published: October 2019

Objectives: Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative therapy for patients with chronic myeloid leukemia (CML) in blast crisis (BC). Haploidentical donors (HID) are immediately available for almost all of them. We compare the outcomes of HID transplantation with those of matched related donor (MRD) transplantation in cohort study.

Methods: We studied 90 T-replete HID (n=67) and MRD (n=23) HSCT for CML-BC patients in our center from Jan 1st, 2001 to September 30, 2013. After transplantation, patients received tapering immunosupressant or TKI or donor lymphocyte infusion (DLI) or combined therapy as intervention based on BCR-ABL levels.

Results: Of the 86 engrafted patients, 30 received intervention after transplantation. The 1-year cumulative incidence of intervention in HID transplants was significantly lower than in MRD transplants, 24.7% vs. 56.5% (P=.002). At 3 years, overall survival (OS) was similar (60.0% vs. 53.3%), 3-year event-free survival (EFS) higher (35.8% vs. 13.0%; P=.002) in HID transplants. Three-year incidences of transplant related mortality (TRM) and relapse did not significantly differ.

Conclusions: HID transplantation achieves comparable OS with less post-transplant intervention, which is not inferior to MRD in CML-BC patients, and might be regular donors for those who need urgent transplantation.

Disclosures

No relevant conflicts of interest to declare.