bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of IRF4 Results in Multiple Myeloma Cell Apoptosis through the Transcriptional up-Regulation of the BH3-Only Proteins Bmf and BIM
Authors: Fedele Pasquale L. , Liao Yang , Gong Jianan , van Delft Mark , Low Michael S.Y. , Tai Lin , Herold Marco J , Tellier Julie , Grigoriadis George , Huang David C.S. , Shi Wei , Nutt Stephen , Willis Simon
Published: November 2019

The transcription factor IRF4 is essential for the survival of both normal plasma cells and the plasma cell malignancy multiple myeloma (MM). However the basis for this dependency remains uncertain, with the prevailing view that IRF4 loss in MM induces "death by a thousand cuts."

Here we have explored the genetic basis for IRF4 addiction through CRISPR-Cas9 mediated deletion of IRF4 in three lenalidomide sensitive MM cells lines (MM1S, OPM2 and H929) and one resistant cell line (RPMI-8226). Loss of IRF4 resulted in marked loss of viability, irrespective of lenalidomide sensitivity, which was driven by two distinct mechanisms: 1) induction of apoptosis, which was rescued through prior deletion of apoptotic mediators BAX and BAK, and 2) proliferative arrest, which persisted despite rescue from apoptosis.

RNA-sequencing following IRF4 inactivation identified a core group of 86 genes whose dysregulation was shared across all 4 MM cell lines. We identified 31 common down-regulated genes (IRF4 activated), including several with previously described roles in survival (such as KLF2, TNFRSF17/BCMA and MYB). Furthermore, MYC, a previously identified target of IRF4 known to play an important role in MM pathogenesis and survival, was down-regulated in 3 of the 4 cell lines.

Most surprisingly, IRF4 inactivation resulted in 55 common up-regulated genes that included two BH3-only pro-apoptotic proteins, BMF and BCL2L11 (BIM). Up-regulation of BMF appeared more marked than BIM with an average fold change of 6.5x (range 2.7 - 10.3) vs 1.9x (range: 1.8 - 2.2) respectively. Remarkably, genetic ablation of BMF in the OPM2 cell line and BMF/BIM in the MM1S largely protected from the cell death observed following IRF4 inactivation, suggesting that IRF4 maintains MM survival through the transcriptional repression of BMF and BIM.

Our results confirm the vital role of IRF4 for MM proliferation and survival, and shed further light into its critical downstream transcriptional targets. Most interestingly, we have demonstrated that the 'killer blow' appears to be the concerted effect of the BH3-only pro-apoptotic proteins BMF and BIM.

Disclosures

Huang: Genentech: Patents & Royalties: DCSH is an employee of the Walter and Eliza Hall Institute which receives milestone and royalty payments related to venetoclax.
Implementing a Structured Health Care Transition (HCT) Process for Sickle Cell Disease (SCD) Using Quality Improvement (QI): Early Results of a SCD HCT Learning Collaorative
Authors: Osunkwo Ifeyinwa (IFY) , Cheryl Courtlandt , Patterson Charity , Laura Noonan , Cornette Jennifer , McManus Peggy , Patience White , Lawrence Raymona Holloway
Published: November 2019

Background: A regional SCD HCT learning collaborative (SCD-LC) was formed from engaging 14 pediatric and adult paired sites (including required community participation) using a standardized HCT quality improvement process. The SCD-LC involved a kick-off meeting and monthly calls to establish a common understanding of clinical recommendations, QI methods, and implementation of the Six Core Elements of HCT (6CE).

Methods: Implementation of 6CE was measured as part of a SCD HCT Study conducted in 14 paired SCD clinical sites with pediatric, adult and community partners who care for 1625 individuals aged 16-25. They represent a variety of clinical programs:12 urban and 2 rural, 12 academic and 2 nonacademic, 6 small and 8 large. Got Transition's Process Measurement Tool (HCTPMT) was customized for SCD and used to assess 6CE implementation. HCTPMT were completed by 14 pediatric and 14 adult sites at baseline (2018) and after 6 months. Pre-post results were compared overall and by type of practice.

Results: All 14 participating sites made substantial progress towards implementing a structured HCT process consistent with the within the first 6 months of the project. Overall, baseline scores averaged 19.4 (SD 14.1) and after 6 months of QI support, scores increased to 33.7 (SD 19.4) (average change 14.3, p<0.0001). For the 14 pediatric sites, scores went from 24 to 43 (p 0.0016), and for the 14 adult sites, from 15 to 24 (p 0.0017). Pediatric sites had higher scores at 6 months compared to adult sites (p=0.0068). Although their change over time was higher, it did not reach statistical significance at 0.05 (p=0.0759). Large sites went from 21 to 34 (delta 14, p=0.0048), small went from 18 to 32 (delta 15, p=0.0018).

Conclusion: All 14 pediatric and adult sites reported significant progress within 6 months of implementing a structured HCT process aligned with the 6CE.

Disclosures

Osunkwo: Novartis: Consultancy, Speakers Bureau; Pfizer: Consultancy; Terumo: Speakers Bureau; Micella Biopharma: Other: DSMB Member .
Pre-Emptive Tyrosine Kinase-Inhibitor Intervention Based on BCR/ABL1 Monitoring in Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia after Allo-HSCT: Two Independent Observational Cohort Study
Authors: Hui Liu , Xuan Li , Lin Ren , Deng Lan , Huang Fen , Fan Zhiping , Nie Danian , Li Xudong , Liang Xinquan , Xu Dan , Zhang Yu , Xu Na , Ye Jieyu , Jin Hua , Lin Dongjun , MA Liping , Sun Jing , Huang Xiaojun , Liu Qifa
Published: November 2019

Relapse is a major cause of treatment-failure in persons with Philadelphia-chromosome-positive acute lymphoblastic leukemia (Ph+ALL) receiving an allogeneic hematopoietic cell transplant. There is controversy whether post-transplant tyrosine kinase-inhibitors (TKIs) reduces relapse risk. We evaluated a pre-emptive strategy in 103 subjects in a prospective study with prophylactic group as historical control. Subjects were tested for measurable residual disease (MRD) by assaying levels of BCRABL1 transcript. MRD was considered positive if the levels of BCRABL1 transcript were >=10-5. Subjects with positive MRD post-transplant received TKI-therapy. The chosen of TKIs was based on BCRABL1 mutation, and donor lymphocyte infusion (DLI) was recommended in those who were not responsive to TKIs. The primary endpoint was relapse (including hematological relapse and central nervous system relapse). Twenty-three of 103 subjects were MRD-positive post-transplant. Seven of whom had BCRABL1 mutations including T315I (N=5). Pre-emptive therapy resulted in 21 subjects being MRD-test negative. The overall 3-year cumulative incidence of relapse (CIR) post-transplantation was 11% (95% confidence interval [CI], 4, 17%) and 34% (22,1, 46.5%) in the pre-emptive and prophylactic maintain group (P=0.030). The 3-year cumulative survival and LFS post-transplants in the pre-emptive and prophylactic group were 87% (80, 94%) and 63% (51, 75%), and 83% (76, 91%) and 58% (46, 70%) (P=0.000 and P=0.000, respectively). The multivariate analysis showed that positive MRD pre-transplantation was the risk factor for relapse, LFS and survival [HRs=8.977(3.344, 24.096; P=0.000), HRs=4.763 (2.153, 10.538; P=0.000) and HRs=7.535 (2.977,19.071; P=0.000], while pre-emptive therapy was the protective factor for relapse, LFS and survival [HRs=0.176 (0.077, 0.339; P=0.000), HRs=0.222 (0.107, 0.462; P=0.000) and HRs=0.188 (0.082,0.43; P=0.000)]. Our data suggest a pre-emptive strategy based on MRD-test monitoring and mutation analyses might reduce CIR and improve survival after allotransplants for Ph+ALL (NCT 01883219).

Disclosures

No relevant conflicts of interest to declare.
On Demand Plerixafor As a Rescue Strategy in Healthy Donors to Achieve Adequate Stem Cells - a Pilot Study from South India
Authors: Kumar Kishore , Kumar Kishore , Subash Chezhian
Published: November 2019

Aims & Objectives: The aim of the study is to check the safety and feasibility of using Plerixafor in healthy donors who have failed to mobilise > 2 x 10 6/kg of CD34 cells on day 1 of aphresis. The indication at present remains off label.

Patients/Materials & Methods: Seventeen healthy donors, all more than 18 years of age were enrolled in this study after a proper written informed consent who failed to mobilise adequately on day 1 collection. The dose of Plerixafor used was 0.24mg/kg body weight of donor, 10-11 hours before the aphresis procedure. The GCSF was given from day -5 and the last dose was given 4 hours before the second day aphresis. CD34 was done in pre-aphresis peripheral blood and in product bag and compared with day 1 data.

Results: The median donor bw was 54 kg (IQR, 42 kg to 69 kg) and the median recipient bw was 58 kg (IQR, 44 kg to 76 kg).The median CD34+ count in peripheral blood was 11.2/µl on day 4 after G-CSF alone and 24.7.0/µl on day 5 after G-CSF plus Plerixafor. The use of Plerixafor increased the number of circulating CD34 cells in peripheral blood by 2.2 fold.There were no major side effects except for the manageable bone pains which can be attributed to GCSF also. There were no differences in the engraftment statistics and rates of GVHD in comparison to historical cases. Though this is not a randomised control study to compare with second day high dose GCSF cases, the amount of increase in stem cells were statistically significant comparing with historical controls(p< 0.05). After a median followup of six months, no adverse effects were noted in donors.

Discussion & Conclusion: Plerixafor is well tolerated in healthy donors and can be used safely in situations of poor mobilisers or when there is a significant difference in weight of donor to receipient. Its a small pilot study. We need a proper randomised control study and a longer follow up to look infor the side effects on healthy donor.

Disclosures

No relevant conflicts of interest to declare.
The Contribution of Proteasome Subunits to Myeloma Cell Viability and Proteasome Inhibitor Sensitivity
Authors: Shi Chang-Xin , Zhu Yuan Xiao , Bruins Laura Ann , Bonolo De Campos Cecilia , Stewart William , Braggio Esteban , Stewart A Keith
Published: November 2019

Background

Bortezomib (BTZ) is highly effective in the treatment of multiple myeloma; however, emergent drug resistance is common. The underlying mechanisms of such proteasome inhibitor resistance are still incompletely understood.

Methods

To further understand its resistant mechanism, we generated eight multiple myeloma (MM) cell lines resistant to bortezomib (BTZ) by exposure to increasing drug concentration: five of them acquired novel PSMB5 mutations. Given the rarity of similar mutations in over 1,500 analyzed MM patients, we explored in depth the role of the proteasome on MM cell viability and BTZ sensitivity by systematically deleting the major proteasome targets of BTZ by CRISPR.

Results

We demonstrated that MM cell lines without PSMB5 were surprisingly viable (mutation corresponding yeast gene pre2 is lethal). PSMB5 mutated, BTZ resistant, MM cell lines were re-sensitized to BTZ when PSMB5 was experimentally deleted, implying that this mutation is activating in its drug resistance function. In contrast PSMB6 knockout was lethal to MM cell lines, which were efficiently rescued by re-introduction of wild type PSMB6. Interestingly, reduction in PSMB6 levels also prevented the splicing of the major catalytic subunits PSMB5, PSMB7, PSMB8 and PSMB10. PSMB6 engineered with no splicing function or catalytic activity, also restored viability, inferring that the contribution of PSMB6 to proteasome structure is more important than functional activity. Supporting this observation, BTZ sensitivity was restored in resistant MM cells line by introducing low level expression of mutated PSMB6 lacking splicing function. As with PSMB6, PSMB7 knockout was lethal to MM cell lines. In contrast, loss of immunoproteasome subunits PSMB8 and PSMB9 was neither lethal nor restored sensitivity to BTZ. Our results demonstrate that expression of the three constitutive proteasome subunits PSMB5, PSMB6 and PSMB7 is highly co-dependent. This dependence is relying on the structure, but not the function, of PSMB5 and PSMB6.

Conclusions

In summary, PSMB5 and PSMB6, but not PSMB8 and PSMB9, are highly relevant for BTZ sensitivity in MM. Absence of PSMB6 or PSMB7, but not PSMB5, was lethal in MM cell lines. Expression of PSMB5, PSMB6 and PSMB7 was highly co-dependent. Together these findings suggest that the modulation of expression rather than function of PSMB5, PSMB6 or PSMB7 may be a new therapeutic strategy.

Disclosures

No relevant conflicts of interest to declare.
Efficacy and Safety of CAR-T Therapy with Safety Switch Targeting Bcma for Patients with Relapsed/Refractory Multiple Myeloma in a Phase 1 Clinical Study
Authors: Fu Weijun , Du Juan , Jiang Hua , CHENG Zhi , Wei Runhong , Yu Kang , Jiang Songfu , He Feng , Fang Hongliang , Liu Yarong , Wang Pin
Published: November 2019

Background: Encouraging results are seen from several early phase clinical trials on the cellular immunotherapy based on chimeric antigen receptor (CAR)-engineered T (CAR-T) targeting B cell maturation antigen (BCMA) for the treatment of relapsed/refractory (RR) multiple myeloma (MM). We developed an anti-BCMA CAR-T cell product manufactured via gamma-retrovirus-mediated transduction of activated T cells to express a second-generation CAR with the 4-1BB costimulatory domain along with a truncated epidermal growth factor receptor (tEGFR) as a safety switch. The preclinical study confirmed its high reactivity against MM cells. Methods: A phase 1 clinical trial (NCT03093168) has been launched to evaluate the safety and feasibility of this BCMA CAR-T cell product for treating RRMM. The enrolled RRMM patients had received at least 2 prior treatment regimens, including a proteasome inhibitor and an immunomodulatory agent, or are double-refractory, and have over 5% BCMA expression on plasma cells (Nine patient with extramedullary plasmacytoma does not express BCMA). Patients were subjected to a lymphodepleting regimen with Cy (300 mg/m2, d-5 to d-3) and Flu daily for 3 days (25 mg/m2, d-5 to d-3) prior to the CAR-T infusion (d0) at a dose of 9×106CAR+ cells/kg. The efficacy was assessed by the International Uniform Response Criteria for Multiple Myeloma, and the toxicity is graded by CTCAE 4.03. Results: As of March 1th, 2019, 46 patients had been infused with this intended dose of the autologous BCMA CAR-T cells, and 44 patients had reached at least 1 month of follow-up. As of this data cut-off, the overall response rate (ORR) for the 44 evaluable patients was 79.6%, including 2sCRs, 16CRs, 8VGPRs and 8PRs, and 16 patients reached MRD-negative response. The CAR-T cell expansion and persistence were consistently observed throughout these patients. The medianPFS is 15mon, and the median OS result has not been reached (49.16% progression-free survival, and 53.95% overall survival at 24 months). Among the 44 infused patients, 22.7% had grade 1-2 Cytokine release syndrome (CRS ) and 6.8% (3 patients) had grade 3 CRS. No grade 4 CRS reactions developed and all toxicities were fully reversible. Conclusions: Our result demonstrates the high potential of this single CAR-T infusion therapy for RRMM, including 2sCRs, 16CRs and ongoing clinical responses for more than 26 months, with manageable CRS to date. These initial data provide strong evidence to support the further development of this anti-myeloma cellular immunotherapy.

Disclosures

No relevant conflicts of interest to declare.
Safety and Anti-Tumor Activity Study of Loncastuximab Tesirine and Durvalumab in Diffuse Large B-Cell, Mantle Cell, or Follicular Lymphoma
Authors: Moskowitz Craig H. , Bastos-Oreiro Mariana , Ungar David , Dautaj Ilva , Kalac Matko
Published: November 2019

Introduction:

Loncastuximab tesirine (Lonca) is an antibody-drug conjugate (ADC) comprising a humanized anti-CD19 antibody (Ab) conjugated to a pyrrolobenzodiazepine dimer toxin. In a Phase 1, first-in-human ADCT-402-101 clinical study, Lonca demonstrated single-agent anti-tumor activity with manageable toxicity in patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL) and follicular lymphoma (FL). Durvalumab is a human monoclonal Ab of the immunoglobulin G-1 kappa subclass that blocks the interaction of programmed death-ligand 1 (PD-L1) with PD-1 on T-cells and with CD80 (B7.1) on other immune cells. Blockade of PD-L1/PD-1 and PD-L1/CD80 interactions releases the inhibition of immune responses, including those that may result in tumor elimination. Preclinical data, as well as early results from clinical trials combining ADCs and checkpoint inhibitors, show potentially increased effectiveness of these therapeutics when used in combination and provide the rationale for the current trial.

Study Design and Methods:

This is a Phase 1b, open-label, dose escalation (Part 1) and expansion (Part 2) trial of Lonca combined with durvalumab in patients with R/R DLBCL, MCL, or FL (NCT03685344). The key inclusion and exclusion criteria for the ADCT-402-104 study are reported in Table 1, and the dosing schema is presented in Figure 1. This trial will evaluate the safety and tolerability, preliminary anti-tumor activity, pharmacokinetics, pharmacodynamics, and immunogenicity of Lonca combined with durvalumab. Patients will receive Lonca once every 3 weeks for 2 doses in total, and durvalumab every 4 weeks for up to 1 year. Patients with only partial response or stable disease at the second disease evaluation may receive 2 additional doses of Lonca given once every 3 weeks. During Part 1, the dose of Lonca will be escalated using a classic 3+3 design with a fixed dose of durvalumab. Part 2 will consist of up to 3 expansion cohorts, one for each of the DLBCL, MCL, and FL populations. All patients in Part 2 will receive the dose of Lonca determined in Part 1, with a fixed dose of durvalumab. The trial opened in February 2019 and recruitment is ongoing.

Study sponsored by ADC Therapeutics SA with the support of MedImmune Limited, a wholly-owned subsidiary of AstraZeneca Pharmaceuticals PLC, which supplies durvalumab (http://clinicaltrials.gov/show/NCT03685344).

Disclosures

Moskowitz: ADC Therapeutics: Research Funding; Merck: Consultancy, Research Funding; Celgene: Consultancy; Pharmacyclics: Research Funding; Seattle Genetics, Inc.: Consultancy, Research Funding; Genentech: Consultancy, Research Funding. Ungar:ADC Therapeutics: Employment, Other: Stock options. equity interest. Dautaj:ADC Therapeutics: Employment, Other: Stock options.
ABO Blood Groups and the Risk of Venous Thromboembolism (VTE) Among Saudi Patients at a Tertiary Care Hospital in Riyadh
Authors: Kullab Ghaydaa Juma , Zaidi Abdul Rehman Z. , Albaqmi Sultan , Alajlan Haya , Alsheef Mohammed Abdullah
Published: November 2019

Background:

ABO blood types are scientifically proved to be associated with the risk of venous thromboembolism (VTE), but data is lacking in the Saudi population.

Aims:

We aimed to investigate the association between ABO blood types and VTE, to explore potential interactions between ABO blood type with sex and obesity status.

Methods:

This was a retrospective study with a total of 998 patients, who were admitted with venous thromboembolism at our tertiary care hospital, between January 2010 and January 2018. Demographic and clinical data were collected. We used chi-square tests to assess the association between ABO blood group and the development of VTE. It was decided that the test will be considered significant if the p-value is <0.05.

Results:

Out of 998 VTE patients, 506 of patients were excluded, because their ABO blood group was not tested. Therefore, 492 patients were qualified as study subjects, of whom 66% of patients had DVT, 23% of patients had pulmonary embolism. Most of them had provoked VTE. Female patients constituted the majority of the study subjects (82.5%). Sample distribution appeared that O blood group was present in 34.1% of all VTE patients, while non-O-blood groups were present in 66% of them. Overall, there was a non-significant difference between VTE in patients with non-O blood type compared to O blood type (p=0.268).

Conclusions:

Non-O-blood groups (A, B, AB) are the most common blood types in Saudi patients with VTE. There is no statistically significant association between ABO blood groups, gender, and obesity status.

Disclosures

No relevant conflicts of interest to declare.
TP53 Abnormality in Myelodysplastic Syndrome
Authors: Huang Fei , Chen Yu , Zhu Yuxing , Qiao Chun , Qian Sixuan , Li Jianyong , Shen Wenyi
Published: November 2019

TP53 (tumor suppressor gene P53), one of the most important tumor suppressor genes, plays an important role in cell cycle arrest, cell senescence, apoptosis, differentiation and metabolism. The TP53 gene is located on 17p13.1, its encoded product is the transcription factor P53 protein, which is known as the "the guardian of the genome". Alterations of TP53 include mutations and deletions and are generally associated with advanced stages of disease, insufficient therapy-response and poor prognosis.

The main purpose of our study was to comprehensively analyze the TP53 mutation and 17p deletion in MDS in our single center. To better understand the relationship between TP53 abnormality and clinical phenotype, prognosis, leukemia transformation, therapeutic response of MDS. Next generation sequencing (NGS) method combining with cytogenetics analysis were used, 36 common related AML/MDS/MPN related genes such as TP53, TET2, WT1, ASXL1, U2AF1, RUNX1, etc were covered. According to the 2016 WHO classification and prognosis score system and from June 2011 to June 2017, 88 newly diagnosed MDS patients including 17 MDS-SLD, 32 MDS-MLD,6 MDS-RS,19 MDS-EB-1,11 MDS-EB-2 and 2 MDS-U, 1 5q- syndrome were enrolled. TP53 mutation/deletions were found in twenty-two (25%) of the 88 newly diagnosed MDS patients, among them,7 MDS-SLD, 4 MDS-MLD, 2 MDS-RS, 1 5q-, 6 MDS-EB-1 and 6 MDS-EB-2. TP53 mutation/deletions cases had a higher proportion of bone marrow blasts compared with TP53 negative cases (P=0.009), At the same time, TP53 positive were highly correlated with MDS-EB-2 subtype (P=0.025), complex karyotype (P<0.001). Based on a median follow-up time of 21(1-267) months in all pts, 13 patients (14.8%) progressed to AML and pts with TP53 mutation/deletions tended to progress to AML (P=0.056) with a shorter OS (P=0.005) and PFS (P=0.001). NGS data of accompanying mutation in other classical leukemia genes shown that compound TP53 and U2AF1 mutations were significantly associated with disease progression. For TP53 mutation/deletion group (n=22), we further sequenced the TP53 status at multiple time point of pre and after DAC treatment, results shown that all patients had persistent TP53 positive status before and after treatment.

In conclusion, our results indicate that in MDS TP53 mutation/deletions is highly correlated with MDS-EB-2 subtype, IPSS high-risk group, and complex karyotype. TP53 mutations that occur in the early stages of MDS may contribute to disease progression and leukemia transformation in conjunction with other molecular abnormalities. DAC improves outcomes in patients with TP53 mutation/deletion but may not clear TP53 mutations.

Disclosures

No relevant conflicts of interest to declare.
Dual Epigenetic Agents Plus Rituximab-Gemcitabine-Oxaliplatin As a Salvage Treatment in Relapsed/Refractory Diffuse Large B Cell Lymphoma Patients
Authors: Qu Changju , Ping Nana , Kong Danqing , Xia Fan , Wu Depei , Jin Zhengming
Published: November 2019

Background: Chemo-resistance is a core challenge in successful treatment of diffuse large B cell lymphoma (DLBCL). It has been previously reported that DNA hypermethylation and histone deacetylation are two major epigenetic modifications contributing to chemo-resistance in multiple tumors. Moreover, combination of histone deacetylase inhibitors (HDI) and DNA methyltransferase inhibitors (DNMTI) resulted in synergistic anti-lymphoma effect toward refractory and/or relapsed (R/R) DLBCL cells in vitro and in vivo xenografts. R-GemOx (rituximab, gemcitabine, and oxaliplatin), as a first-line chemotherapy regimen for elderly primary DLBCL patients or a salvage chemotherapy regimen for R/R DLBCL patients not candidates for high-dose therapy, has shown high activity with a relative low toxicity profile. Herein, we therefore aimed to assess the efficacy, safety, and feasibility of the dual epigenetic agents plus R-GemOx regimen (CD-R-GemOx) as a salvage treatment in R/R DLBCL patients.

Methods: 13 R/R DLBCL patients including 8 males and 5 females, diagnosed with R/R DLBCL on the basis of the 2008 World Health Organization guidelines, who had failed from previous salvage treatment were exposed to dual epigenetic agents (Chidamide 30mg biw and Decitabine 10mg/m2 qd d1-d5) and sequential R-GemOx(rituximab 375 mg/m² qd d6; gemcitabine 1 g/m² d7,d14; and oxaliplatin 100 mg/m² d8) for salvage chemotherapy. Median age of these patients was 56 (35-67) years old. Most (10/13) patients have advanced Ann Arbor stages. The cycle was repeated every 4 weeks. Clinical efficacy were assessed after two cycles.

Results: All thirteen (100%) patients achieved disease control response. Ten (76.9%) patients achieved an overall response at the end of the treatment, with three (23.1%) achieving a complete response. Common grade 3-4 adverse events were haematological toxicities (thrombocytopenia in ten [76.9%] patients, anaemia in six [46.2%], and neutropenia in twelve [92.3%]) and gastrointestinal complications (nausea in four [30.8%] patients, vomiting in one [7.7%], diarrhoea in six [46.2%] and mucositis in six [46.2%]). Besides, 6/13 (46.2%) cases manifested with pyrexia; 3/13(23.8%) cases manifested with increase of ALT and hyperbilirubinemia. All above toxicities were reversible and recovered within 1 month after chemotherapy. No neurological toxicities and treatment-related deaths were observed.

Conclusions: Our study indicates that combination of dual epigenetic agents and R-GemOx is a safe and promising salvage approach to managing R/R DLBCL patients and may serve as an optimal salvage treatment for bridging autologous transplantation.

Disclosures

No relevant conflicts of interest to declare.
Impact of Comorbidities on Survival of Chronic Myeloid Leukemia Patients Treated with Tyrosine Kinase Inhibitors
Authors: Engelbrecht Fernanda F , Miranda Eliana C , Delamain Marcia Torresan , Duarte Gislaine Borba , Souza Carmino Antonio , De Paula Erich V , Pagnano Katia B
Published: November 2019

Tyrosine kinase inhibitors treatment changed dramatically the survival of CML patients, approaching to the survival of the normal population. Comorbidities may also impact treatment results.

Aim: to investigate the impact of comorbidities in the survival of CML patients treated with TKI

Methods: We collected clinical and laboratory data from CML patients treated in a single center from medical records from January 2001 to December 2018. Comorbidities were collected at diagnosis before treatment and Charlson comorbidity index (CCI) was calculated. Because of CML diagnosis, the lowest possible score was 2. Patients were treated with imatinib 400-600 mg and one was treated with dasatinib in first line. Management followed the European Leukemia Net recommendations. OS probabilities were calculated using Kaplan-Meier method. OS was defined as the time between diagnosis and death of any cause, independent of treatment. Cox models were estimated for the multivariate analysis. All calculations were performed with version 24.0 SPSS software.

Results: We included 273/310 patients in this analysis; 37 pts were excluded because of previous treated in other centers. Patients characteristics: 57.3% males, median age at diagnosis was 49 (14-86); 263 (96%) chronic phase and 11 (4%) accelerated phase; Sokal low risk 36.8%, intermediate 31.8% high risk 31.4%; EUTOS low risk (81.7%) and high risk (18.3%); median follow-up time was 92 months (1-223). Most frequent comorbidities: hypertension (27.2%); diabetes (7.5%). Smoking at diagnosis (15.3%). CCI group categories were: 2 (n=131), 3 (n=52), 4 (n=46), 5 or more (n=45). Probabilities of OS at 10 years for patients with CCI 2, 3 to 4 and ≥ 5 to were 81%, (95% confidence interval [CI]: 73-89%), 77% (95%CI: 63-100%), 69% (95%CI:53-85%), and 62% (95% CI: 38-86%), respectively. Probabilities of OS according to Sokal score was 86% (low risk) vs. 73% (intermediate) vs. 68% (high risk), P=0.002 and for EUTOS score 79% (low risk) vs. 61% (low risk), P=0.004. OS was lower in patients with hypertension (63% vs. 80%), P=0.018. In a multivariate analysis including CCI Sokal and EUTOS Score, smoking, diabetes, hypertension, the most powerful predictive factors for death were high and intermediate Sokal score and hypertension ((Wald test, P =0.003 and 0.049, respectively). There were 58 deaths, 22 not related to CML and 2 causes unknown.

Conclusions: Comorbidities represents an important cause for mortality in CML patients treated in real life, besides known disease risk factors as Sokal and EUTOS scores. CCI high scores and hypertension were related to a lower OS.

Figure 1

Disclosures

Delamain: Novartis: Honoraria. Pagnano:Abbvie: Consultancy; Sandoz: Consultancy; Pint Pharma: Consultancy.
Predictors of Heparin-Induced Thrombocytopenia in Adult Cardiac Surgery Patients
Authors: Allan Kari , Crow Jessica , Chasler Jessica , Athale Janhavi , Lindsley John , Streiff Michael B. , Dane Kathryn
Published: November 2019

Background: The 4Ts, HIT-Expert Probability (HEP), and Post-Cardiopulmonary Bypass (CPB) screening tools for heparin-induced thrombocytopenia (HIT) have not been validated in cardiac surgery patients. Evidence remains unclear regarding which screening tool most accurately predicts HIT in this population.

Methods: HIT-positive and HIT-negative patients who underwent on-pump cardiac surgery within a six-year period were matched 1:2 in a case-control design. Each patient was scored with the 4Ts, HEP, and CPB tools. Sensitivities and specificities of each tool were calculated using standard cut-offs. The Youden method was utilized to determine optimal cut-offs in receiver operating characteristic (ROC) curves of each score, then sensitivities and specificities were recalculated. A multivariable logistic regression was performed to determine the association of scoring tool components and relevant clinical characteristics with HIT.

Results: Using standard cut-offs for the scoring tools, sensitivities for the CPB, HEP, and 4Ts tools were 100%, 93.9%, and 69.4%, respectively. Specificities were 51%, 49%, and 71.4%, respectively. Using the Youden method-derived optimal cut-offs, sensitivity of the CPB score remained 100% with improved specificity to 88.9%. Sensitivity of the 4Ts score declined to 51% and specificity improved to 93.9%. Pattern of platelet decline, absence of clinically significant bleed, body mass index, coronary artery bypass graft surgery, and postoperative heparin duration were significantly associated with HIT.

Conclusions: The 4Ts score has limited utility in cardiac surgery patients, whereas the CPB and HEP scores with standard cut-offs demonstrated high sensitivity but low specificity. A cut-off of 3 points or higher on the CPB score could increase specificity while preserving high sensitivity.

Disclosures

Crow: Research Point Global: Other: Clinical and coding data review services. Streiff:Pfizer: Consultancy, Honoraria; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Daiichi-Sankyo: Consultancy, Honoraria; Roche: Research Funding; Portola: Consultancy, Honoraria; Bayer: Consultancy, Honoraria.
Cell Type-Specific Effects of Crizotinib in Human Acute Myeloid Leukemia with TP53 Alterations
Authors: Antony Marie Lue , Noble-Orcutt Klara , Ogunsan Oluwateniayo , He Fiona , Sachs Zohar
Published: November 2019

Introduction: In acute myeloid leukemia (AML) standard therapies induce complete remission in 50-70% of patients, but overall two-year survival is less than 20-30% because of high relapse rates. AML with TP53 alteration is largely insensitive to chemotherapy, modern targeted agents, and hematopoietic stem cell transplantation. Mutations in TP53 are seen in approximately 20% of AML and confer a particularly poor prognosis decreasing the 1-2 year survival rates to 0-10%. Leukemia stem cells (LSCs) are defined as the cells that recapitulate the leukemia and cause relapse. Recent large-scale drug-screening efforts to map treatment vulnerabilities in AML have revealed that crizotinib can reduce the in vitro viability of unselected primary human AML bone marrow samples with TP53 alterations (Tyner et al. Nature 2018). Crizotinib is a tyrosine kinase inhibitor that targets ALK, MET, and RON and is FDA approved for treatment of lung cancer. Since LSCs are largely responsible for AML mortality, we investigated whether crizotinib targets LSCs in primary, diagnostic human AML samples with TP53 alterations. We used mass cytometry (CyTOF2) to determine the cell-type specific effects of this drug on intracellular signaling states. We profiled treated samples with a panel that includes immunophenotypic markers (including LSC markers) and intracellular signaling molecules implicated in AML pathogenesis and aggressiveness.

Results: Primary human AML samples with TP53 alterations were treated with crizotinib (10 mM, n=3). There was a reduction of viability by 48 hours of in vitro treatment with crizotinib, relative to vehicle (mean 64% reduction in viability). Crizotinib abolished all colony formation in semi-solid media. Mass cytometry analysis revealed that crizotinib treatment led to a loss of cells bearing LSC-specific markers such as CD123 and TIM3. Crizotinib treatment also induced a consistent loss of phosphorylated-signaling intermediates of the STAT and p38/MAPAPKII pathways in all samples tested. Notably, crizotinib treatment also induced significant reductions in total and phosphorylated NFKB in all samples tested.

Conclusions: These data reveal cell-type specific effects of crizotinib in human AML with TP53 alterations. Crizotinib induced a specific loss of LSCs and inhibition of the STAT, p38/MAPAPKII and NFKB pathways. These data suggest that crizotinib inhibition may target LSCs in AML with TP53 alterations.

Figure

Disclosures

No relevant conflicts of interest to declare.
Prognostic Value of Diffusion-Weighted Magnetic Resonance Imaging in Newly Diagnosed Multiple Myeloma Patients Treated with up-Front Autologous Transplantation
Authors: Fernández-Poveda Elena , Cabañas Valentin , Moreno Maria José , Blanquer Blanquer Miguel , Moraleda José M
Published: November 2019

Background and aims:

Bone disease extension in symptomatic multiple myeloma (MM) has prognostic implications. However, methods better than the traditional ones are necessary to establish the diagnosis according to the updated International Myeloma Working Group criteria (IMWG).

Magnetic resonance imaging (MRI) is a novel technique to detect bone lesions at diagnosis. The IMWG has incorporated it to the diagnostic work-up. However, due to MRI false-positive results in non-viable lesions, PET-TC is preferred during follow-up to assess prognosis.

Diffusion-weighted magnetic resonance imaging (DW-MRI) uses the diffusion of water in the bone marrow, which is greatly influenced by cellularity and tumor burden. DW-MRI has been explored for the assessment of minimal residual disease (MRD) after autologous stem cell transplantation (ASCT) in a recently published study, showing better progression free survival (PFS) in patients with negative DW-MRI.

Our aim is to compare the PFS in patients with MM with negative and positive DW-MRI at 3 months of ASCT and to assess the differences with PET-CT.

Methods:

MRI and PET/CT were performed in patients diagnosed with symptomatic MM at 3 months after ASCT. All patients received a Bortezomib based three drugs combination as induction treatment. None received maintenance.

Any ≥5 mm focal lesion seen on PET-CT with standardized uptake value (SUVmax)>2.5 for bone tissue or >3.5 for soft tissues was considered positive.

Any ≥5 mm focal lesion seen on DW-MRI that restricted the diffusion, as well as the presence of extramedullary disease, was considered positive.

Statistical analysis was performed using the Kaplan Meier test and Fisher's exact test.

Results:

The baseline characteristics of the 17 patients included are shown in Table 1.

The median PFS in the positive DW-MRI group was 28 months, whereas the median PFS in the negative DW-MRI group was not reached (p=0.029) (image 1).

Both tests were coincidently positive in 3 patients (17%) and negative in 7 patients (41%). There was no coincidence in the remaining 7 (41%) patients, 5 (29%) being DW-MRI positive and 2 (11%) being PET-TAC positive. The difference was statistically non-significant.

Conclusions:

In our population, patients with negative DW-MRI after ASCT have a significantly higher PFS. These data are favorable to the use of DW-MRI in the follow-up of MM.

Disclosures

No relevant conflicts of interest to declare.
Multicenter Study of Ruxolitinibcombined DEP Regimen As a Salvage Therapy for Refractory/Relapsed Hemophagocytic Lymphohistiocytosis
Authors: Wang Jingshi , Wang Zhao
Published: November 2019

Hemophagocytic lymphohistiocytosis (HLH) is a refractory immune disorder with a significant risk of death.Current therapies have improved the survival of HLH patients; however, approximately 30% patients do not respond to current therapies. At present, there is nounanimously recommended salvage HLH treatment regimen, and there are a few case reports or clinical reports with small sample sizes concerning salvage therapy after first line treatment failure. Therefore, alternative therapies for relapsed/refractory HLH is needed. Previous studies have found that ruxolitinib can improve the inflammatory status well, but the remission depth is not sufficient.

This prospective study aimed to investigate the efficacy of ruxolitinib combined with our previous DEP (doxorubicin-etoposide-methylprednisolone) regimen(DEP-Ru) as a salvage therapy for refractory/relapsed(R/R)HLH.All patients who did not achieve at least partial response 2 weeks after initial standard HLH therapy or relapsed after remission with HLH-94 regimen were enrolled in this study between June 2018 and June 2019. Response to salvage therapy was assessed every 2 weeks after initiation of DEP-Ru therapy and patients were followed until death or until July 2019.

Fifty-four R/R HLH patients were enrolled, including 28 cases of Epstein-Barr virus-associated HLH(EBV-HLH), 5 cases of macrophage activation syndrome (MAS), 3 cases of lymphoma-associated HLH, and 6 cases of familial HLH, 1case of pregnancy, 1 case of drug, and 2 cases of infection. There were 8 cases with unknown underlying diseases. One case was lost to follow-up, Eight cases (15.1%) achieved complete response and 31 cases (58.5%) achieved partial response. The overall response was 73.6% (39/53).Thirty two of the 54 patients survived to subsequent chemotherapy or allogenic hematopoietic stem cell transplantation.

Our study suggests that DEP-Ru regimen compared with DEP regimen had similar efficacy, and no serious complications such as gastrointestinal bleeding occurred in DEP regimen. DEP-Ru has higher efficacy for MAS and HLH with unknown reason , while EBV-HLH and lymphoma-associated HLH have lower efficacy. DEP-Ru regimen is an effective salvage regimen for R/R HLH, which can prolong patient survival and bridge the gap between HLH and its underlying diseases. This study was registered in the Clinical Trail (ClinicalTrails.gov Identifier: NCT03533790).

Disclosures

No relevant conflicts of interest to declare.
Cold Plasma with Immunomodulatory Properties Has Significant Anti-Lymphoma Activities in Vitro and In Vivo
Authors: Cheng Fengdong , Yan Dayun , Chen Jie , Keidar Michael , Sotomayor Eduardo
Published: November 2019

In recent years, cancer immunotherapy has revolutionized cancer care. Remarkable clinical efficacy and durable responses to checkpoint blockade antibodies or to genetically engineered T-cells (CAR T cell) have been observed in patients with multiple cancers. However, not all cancer patients benefit from these therapies and as such novel immunotherapeutic approaches are needed. The cold atmospheric plasma (CAP) is a form of near room temperature ionized gas, which has shown a promising application in cancer therapy given its antitumor effects in vitro as well as in vivo. For the first time, we have shown that upon CAP treatment, the viability of the immune cells remained unaffected. Strikingly, we observed a significantly stronger immune activation of those CAP treated cells when compare with helium gas control. First, we have demonstrated that even without LPS stimulation, in vitro exposure of peritoneal elicited macrophages (PEM) to CAP for 15 or 30 seconds was sufficient to trigger the production of the pro-inflammatory cytokines IL-12 and IL-6. In addition, decreased production of anti-inflammatory cytokine IL-10 and diminished the expression of PD-L1 were observed in CAP-treated PEM as well. It indicated that CAP treatment may potentially facilitate PEMs as better activator of T cells. Second, in lieu of the stimulatory effects of CAP upon PEM, we asked whether CAP could enhance T-cell activation. So we isolated T cells from spleens of C57BL/6 mice and exposed these T cells to CAP followed by anti-CD3/CD28 stimulation. Our study shown that the production of IL-2 and IFN-g were significantly increased by T-cells treated with CAP as compared with helium gas control. Furthermore, to gain insights into effects of CAP upon immune responses in vivo, we isolated lymph nodes from OTII mice and directly exposed these LNs with CAP, helium gas control or left untreated. Then CD4+ T cells were further isolated from the LNs and cultured with macrophages in the presence or absence of OVA peptide for 48 hours, respectively. Surprisingly, CD4+ T cells isolated from CAP-treated LNs displayed enhanced function indicated by its increased production of IL-2 and IFN-g. More importantly, strong in vivo anti-tumor effects were observed when adoptively transfer CAP exposed T cells to lymphoma bearing animals.

Taken together, we have shown for the first time an elevated immune-stimulatory effect of CAP upon both APCs and T cells in vitro and in vivo. Our finding may potentially shed light of a novel therapeutic approach for future cancer immunotherapy.

Disclosures

No relevant conflicts of interest to declare.
Characterisation of Citrullinated TFPI and Truncated TFPI Constructs By PAD4 in Model and Plasma Systems
Authors: Thomassen M.G.L. Christella D. , Suylen Dennis P.L. , Hackeng Tilman M. , Koenen Rory R.
Published: November 2019

Background: The Kunitz type tissue factor pathway inhibitor (TFPI) is an important regulator in hemostasis. Decreased concentrations are a risk factor for thrombosis and complete TFPI deficiency is associated with lethality. TFPI is also reported to be an important link between inflammation and thrombosis. Neutrophil extracellular traps (NETs) formed by NETosis can bind TFPI which then can be cleaved and inactivated by neutrophil elastase (NE) during thrombotic events. In neutrophils, the enzyme peptide arginine deiminase 4 (PAD4) is central in the citrullination of histones prior to the externalization of DNA during NETosis. In this study, we provide evidence that PAD4 also might regulate the activity of TFPI by posttranslational modification of its functional arginines into citrulline.

Aim: To study the effect of citrullination of TFPI and various TFPI constructs on their functional activity on FXa or thrombin generation.

Methods: Citrullination of TFPI by the neutrophil protein PAD4 was studied in a model system (FXa inhibition) and in plasma system (thrombin generation). Various TFPI constructs, Kunitz (K) domains K1K2, K2, and TFPI1-161 were used to study the effects of citrullination on inhibition of FXa. LC-MS was used to locate the specific sites of citrullination.

Results: This study shows that PAD4 very efficiently citrullinates full lenght TFPI. Very low concentrations of PAD4 were sufficient (Ki 0.4 nM) to abolish FXa inhibition by TFPI. Citrullination is calcium-ion, time- and concentration-dependent. The truncated variants K1K2 and TFPI 1-161 and the isolated K2 domain were citrullinated less efficiently by PAD4 than TFPI, implying the presence of specific binding sites for PAD4 at the C-terminus of TFPI. The presence of phospholipids inhibited the citrullination reaction, an effect only seen for TFPI and not for all the other TFPI variants. Thus, the presence of the C-terminus in TFPI appears to be favourable for citrullination by PAD4.

Thrombin generation in TFPI-deficient plasma triggered with TF or Russell's viper venom (RVV)-X showed almost complete absence of anticoagulant activity of citrullinated TFPI

Conclusions: To conclude, only TFPI is very sensitive to citrullination by PAD4. Citrullinated TFPI has lost its ability to inhibit FXa. This process might play a role in the increased thrombosis risk with inflammation. Further experiments are needed to determine the physiologic or pathologic relevance of this process.

Disclosures

No relevant conflicts of interest to declare.
Glucose Metabolism in Sickle Cell Disease
Authors: Hassan Taif , Shah Binal N. , Zhang Xu , Gordeuk Victor R
Published: November 2019

Background. Whether glucose metabolism differs in sickle cell anemia (SCA) patients versus controls is not clear. Transfusional iron overload and Inflammation might enhance glucose intolerance, while lower BMI and increased hypoxic responses might be protective.

Methods: We prospectively determined indicators of glucose metabolism in 46 African-American hemoglobin SS or S/β0-thalassemia subjects >35 years of age who did not have the diagnosis of DM, and examined the relationship of these parameters to BMI and serum ferritin concentration. We compared the SCA subjects to 46 African-American controls from the National Health and Nutrition Examination Study (NHANES) who did not have the diagnosis of DM and were matched by age, sex, BMI and serum ferritin to the SCA subjects.

Results: The BMI was >25 kg/m2 in 23 SCA subjects (48%) and the serum ferritin was >300 ng/ml in 30 (65%) consistent with increased body iron stores. The fasting blood glucose was >125 mg/dL in 3 of 46 SCA subjects (6.5%) suggesting unsuspected DM. The fasting glucose concentration independently correlated with serum ferritin concentration (r=0.336, P=0.024) and the fasting insulin level correlated independently with both BMI (r=0.583, P=0.00002) and serum ferritin (r=0.300, P=0.016). Measures of glucose metabolism did not differ significantly between the SCA subjects and NHANES controls, even though the SCA subjects had lower blood pressures, WBC counts and blood lipid levels.

Conclusions: Measures of glucose metabolism in older SCA patients are similar to controls matched for BMI and iron status despite marked differences in blood pressure, hemoglobin, WBCs and blood lipid levels.

Disclosures

Gordeuk: Inctye: Research Funding; CSL Behring: Consultancy, Honoraria, Research Funding; Ironwood: Research Funding; CSL Behring: Consultancy, Honoraria, Research Funding; Imara: Research Funding; Emmaus: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding; Inctye: Research Funding; Modus Therapeutics: Consultancy, Honoraria; Pfizer: Research Funding; Pfizer: Research Funding; Global Blood Therapeutics: Consultancy, Honoraria, Research Funding; Ironwood: Research Funding; Imara: Research Funding.