bluuebunny/crossref_metadata_2025 huggingface dataset:
Interim and Post-Treatment Positron Emission Tomography-Computed Tomography Scan Status Is Highly Predictive Of Outcome In Diffuse Large Cell Lymphoma Patients Treated With R-CHOP21
Authors: Huang Honghui , Xiao Fei , Chen Fangyuan , Han Xiaofeng , Zhong Lu , Zhong Hua , Xu Lan , Zhu Jianyi , Ni Beiwen , Liu Jia , Chen Tao
Published: October 2019

Background

Taking a step forward from the international prognostic index, attention is focused on the role of 18F-fluorodeoxyglucose positron-emission tomography-Computed Tomography scan (PET) as a tool for guidance in risk stratification in patients with diffuse large B-cell lymphoma (DLBCL). Here, we analyzed the predictive value of interim and post-treatment PET in patients with DLBCL.

Methods

In our retrospective study, we analyzed a homogeneous cohort of newly diagnosed DLBCL patients treated with R-CHOP21 who underwent PET scan at diagnosis, after three cycles of chemotherapy and at the end of treatment. For interim PET, images were interpreted by computing maximum standardized uptake value between PET performed at baseline and after three cycles of immuno-chemotherapy (¦¤SUVmax). The images of post-treatment PET were interpreted visually according to the International Harmonization Project criteria. The primary study endpoints were progression-free survival (PFS) and overall survival (OS).

Results

Thirty-eight patients with DLBCL with PET data were identified. The median follow-up was 28 months. At interim PET evaluation, optimal cutoff to predict progression was 66% for ¦¤SUVmax. ¦¤SUVmax analysis (≥66% vs< 66%) identified patients with significantly different 2-year PFS (90.7% vs 38.9%; P =.000) and 2-year OS (95.5% vs 62%; P=.016) (Fig1). Post-treatment PET status (negative vs positive) was statistically significantly associated with 2-year PFS (91% vs 45.5%; P =.001) and 2-year OS (100% vs 72.7%; P =.012) (Fig2).

Conclusions

These data support the prognostic utility of PET in interim and post-treatment settings in patients with DLBCL treated with R-CHOP21. An interim PET scan after three cycles of treatment can effectively predict the outcome by using quantitative assessment of ¦¤SUVmax and allows clinicians to design a risk-adapted therapeutic strategy. A positive PET after the completion of therapy identifies a patient subset with an inferior PFS and OS.

Disclosures:

No relevant conflicts of interest to declare.
Multicentric Bone Involvement As Presentation Of Late Relapse In a Patient With Hairy Cell Leukemia (HCL)
Authors: Hyppolito Joyce E , Perini Guilherme Fleury , Campregher Paulo Vidal , da cunha Pasqualin Denise , Filho Reynaldo Jesus Garcia , Hamerschlak Nelson
Published: October 2019

Introduction

Hairy Cell Leukemia (HCL) is a lymphoproliferative disease, recently defined molecularly by mutations in the BRAF gene. It has an indolent course, and usually presents with massive splenomegaly, progressive pancytopenia and rare circulating tumor cells. Extranodal involvement, except for liver, is rare in HCL.

Methods

We described the case of a 46 year old female patient diagnosed with HCL in 2008. At that time, patient presented for medical assistance due to pancytopenia (Hb: 8,4g/dL, Leukocytes: 1200uL, Platelets: 29.000). A bone marrow biopsy showed extensive infiltration by lymphocytes positive for CD20, CD11c, CD25 and kappa, compatible with HCL. At that time, biopsy-proven involvement of a mediastinal node was also documented. The patient was treated with Cladribine 0.1mg/kg for 7 days, and achieved complete response.

Five days later, the patient presented with left hip pain. A MRI of the left leg showed nodular involvement of the acetabulum, with edema and bone fissures. A biopsy was consistent with HCL relapse. A PET-CT showed additional lesions in left tibia and right humerus.

Conclusion

Bone involvement in HCL is a rare event, and is usually restricted to one lesion. We present a case of multicentric involvement at relapse.

Disclosures:

No relevant conflicts of interest to declare.
Stroma cells and Monocytes make Multiple Myeloma Cells Active In Bone Marrow Microenviroment
Authors: Ikeda Hiroshi , Ishida Tadao , Hayashi Toshiaki , Aoki Yuka , Shinomura Yasuhisa
Published: October 2019

The Bone marrow (BM) microenvironment plays crucial role in pathogenesis of multiple myeloma　(MM). Paracrine secretion of cytokines in BM stromal cells promotes multiple myeloma cell proliferation and protects against drug-induced cytotoxicity. In current study, monocytes, component of BM cells, can directly promote mesenchymal stem cells osteogenic differentiation through cell contact interactions. Down-regulation of inhibitors such as DKK1 drives the differentiation of mesechymal stem cells into osteoblasts. In this study, we examined the role of monocytes as a potential niche component that supports myeloma cells. We investigated the proliferation of MM cell lines cultured alone or co-cultured with BM stromal cells, monocytes, or a combination of BM stromal cells and monocytes. Consistently, we observed increased proliferation of MM cell lines in the presence of either BM stromal cells or monocytes compared to cell line-only control. Furthermore, the co-culture of BM stromal cells plus monocytes induced the greatest degree of proliferation of myeloma cells. In addition to increased proliferation, BMSCs and monocytes decreased the rate of apoptosis of myeloma cells. Our results therefore suggest that highlights the role of monocyte as an important component of the BM microenvironment.

Disclosures:

No relevant conflicts of interest to declare.
The Detection Of The Immunophenotyping Of Plasma Cells In Patients With Multiple Myeloma
Authors: Ouyang Jian , Li Ermin , Zhou Min , Chen Junhao , Xia Yongquan , Xu Xuejing , Wang Xian , Zhou Rong-Fu
Published: October 2019

Objectives

To study the immunophenotyping of plasma cells in patients with Multiple Myeloma(MM). To explore the antigen combination used to identify benign plasma cells from malignant plasma cells.

Method

Four-color flow cytometry (BD FACSCalibur )was respectively used to detect antigens expression rate of 44 diagnosed patients with MM and 25 normal controls (14 patients with nutritional iron deficiency anemia and 11 healthy bone marrow donators). The results were analyzed by the software of CellQuest. The positive expression rate of clusters of differentiation in cells surface is greater than twenty percent.

Results

The frequency of expression rate of clusters of differentiation among patients with MM are as fellows:CD138+(97.72%) ACD38+(100.00%) ACD56+(63.64%) ACD19-(84.09%) ACD20+(11.63%) ACD200+(77.27%) ACD28+(38.64%) ACD86+(54.55%). The frequency of expression rate among normal plasma cells of controls are CD138+(100.00%) ACD38+(100.00%) ACD56-(0.00%) ACD19+(96.00%) ACD20-(0.00%) ACD200+(0%) ACD28+(0.00%) ACD86+(4.00%).

Conclusions

Using the antigen combination of CD138 ACD38 ACD56 ACD19 ACD20 ACD200 ACD28 ACD86 is availably conducive to detect the phenotype of the malignant plasma cells of the patients with MM.

Disclosures:

No relevant conflicts of interest to declare.
Hemopoiesis Regulated Negatively In Aged Monkeys
Authors: Li Ming , Ikehara Susumu
Published: October 2019

Biological aging is associated with a progressive loss of regulation of cellular, tissue and organ interaction, ultimately resulting in senescence. In humans, accelerated marrow adipogenesis has been associated with aging and several chronic conditions, including diabetes mellitus and osteoporosis. Studies of the hemopoietic system using nonhuman primates have provided important information for understanding the mechanism of human hemopoiesis. Excellent reconstitution of donor hemopoietic cells in a collagen gel group has been observed in the long term in mice. We therefore investigated whether the method would be helpful for reconstituting hemopoiesis in the fatty tibias of monkeys. Nine- to 11-year-old monkeys were used for this study to examine if hemopoiesis could be restored in the fatty marrow of old monkeys. Bone marrow cells were collected from the humerus using the perfusion method, mixed with cultured bone marrow stroma cells in collagen gel, and then injected into the tibia of the same monkey. Clot sections were made from the tibias 1, 2 and 6 weeks after the bone marrow transplantation. However, no bone marrow cells were observed at any of the time points. These results suggested that adipocytes negatively regulate bone marrow reconstitution.

Disclosures:

No relevant conflicts of interest to declare.
A New Murine Model Of Chronic Graft Versus Host Disease
Authors: Huang Xin , Weng Jianyu , Wu Ping , Tong Jiaqi , Lai Peilong , Geng Suxia , Du Xin
Published: October 2019

Chronic graft-versus-host-disease (cGVHD) is a major complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT), with highly variable clinical presentations. The pathophysiology of cGVHD remains to be further understood. The utilization of murine models to study cGVHD has contributed to the understanding of cGVHD, and highlights its mechanistic complexity. Here, we report a new murine cGVHD modle with obvious lung tissue damage in these mice resulted in the development of bronchiolitis obliterans (BO), which is pathopneumonic for cGVHD.

Recipients 8 weeks BALB/c (H-2d) female mice, which irradiated with 700cGy dose of linear accelerator, then were injected with bone-marrow cells (1×107) and spleen cells (5×106) from (C57BL/6 x BALB/c) F1 donors (H-2bd haplotype) male mice. The observed items post-transplantation included hematopoietic reconstruction, implant, and general condition. Clinical scores were assessed every 3 days after +14 d. At + 135 d, mice were killed to evaluate the pathological changes of major target organs.

Mice in transplantation groups were in hematopoietic reconstruction at +7 d, and all survived to the end point (+135 d). Chromosomes of recipient mice were in full donor chimera. Clinical scores of cGVHD group have been more than 0.6 since +90 d. These mice develop pathologic manifestations in several organs including lung, skin, and liver. Biopsy-proven BO incidence was 100%, and pathological scores of cGVHD group were 5.33±1.55, which significantly higher than those of transplantation control groups (P < 0.05).

To date, most models involve parent-into-F1 combinations the transfer of MHC-mismatched cells resulted in a phenotype that resembles clinical systemic lupus erythematosus (SLE), termed SLE-cGVHD. However, some of the models do not use any pretransplantation conditioning and no obvious lung tissue damage. We exchanged parent for recipients, and provide a total boby irradiation as pretransplantation conditioning. New MHC-mismatched murine cGVHD model was easily obtained, and more relevancy to the clinical features of cGVHD. This model provides an ideal study model of clinical cGVHD pathogenesis and treatment strategies.

NOTES: The project was sponsored by grants from National Natural Science Foundation (No. 81270648 and 30972790), National Public Health Grand Research Foundation (No.201202017), and Guangdong Natural Science Foundation (No. S2012010009560).

Disclosures:

No relevant conflicts of interest to declare.
T Cell Receptor Vbeta Repertoire Plays An Important Role In Graft-Versus-Leukemia Effect To Acute Lymphocytic Leukemia With TCF3-PBX1
Authors: Oka Yoko , Shirasaki Ryosuke , Matsuo Takuji , Tashiro Haruko , Ooi Jun , Shirafuji Naoki
Published: October 2019

Background and Aims

We recently reported that graft-versus-leukemia (GVL) effect was observed in acute lymphocytic leukemia (ALL) with TCF3-PBX1 (53rd ASH, and 15th ASGCT). To understand better the mechanism of this GVL effect, we analyzed blood T cell receptors (TCRs) obtained from ALL patients with TCF3-PBX1.

Materials and Methods

The institutional ethical committee approved our study using clinical materials. Three informed ALL patients with TCF3-PBX1 were eligible. Leukemic blasts, blood lymphocytes after underwent allogeneic hematopoietic stem cell transplantation to achieve and keep complete remission, and cells from pathologically GVHD-diagnosed organs (liver, and skin) were collected. Lymphocytes were co-cultured with the patient-derived ALL blasts that were priory irradiated at 20 Gray (GVL model) or GVHD-related cells (GVHD model) for 14 days with recombinant human interleukin-2. Then, TCR Valpha (Va) and Vbeta (Vb) usages were analyzed with RT-PCR. When the preferential usage of Va and Vb was observed, T cells underwent single-cell culture, and the clones showing ALL blast-killing activity and not GVHD effect were selected, and their TCR nucleotide sequences were analyzed.

Results

In GVHD model and GVL one, TCR Va and Vb were oligoclonally used, in which Vb 6, 10, and 14 were preferentially used in GVL model but not in GVHD. On Va no selective usage was demonstrated between GVL model and GVHD one. Furthermore, the obtained single cells with GVL effect had specific TCR Vb nucleotide-sequences.

Discussion

In GVL model TCR Vbs were preferentially used. Currently we isolate tcf3-pbx1-specific oligopeptide-antigen recognized by the isolated TCRs, and observe cytotoxic GVL effect with the isolated TCRs in vitro. We also validate in vivo implications of the isolated GVL-specific T cells to treat leukemic non-obese diabetes/severe combined immunodeficiency mouse generated by the injection of ALL-blast with TCF3-PBX1.

Disclosures:

No relevant conflicts of interest to declare.
Progressive Increase Of Thymoglobulin Severe Infusion Reactions Used In The Conditioning Regimen Of Allogeneic Stem Cell Transplantation. Comparative Study Between 2004 and 2012
Authors: Yanez Lucrecia , Pereira Brenda López , Bermudez Arancha , Insunza Andres , Richard Carlos , Ruiz Mario Gonzalez , Cuaresma Esmeralda , Conde Eulogio
Published: October 2019

Introduction

Thymoglobulin (ATG) infusion-related reactions in stem cell transplant (SCT) recipients are frequent. Minor reactions as fever and chills are the most usually observed. Severe and potentially life-threatening reactions are rare (>1/10.000 and <1/1000) and are associated with hypotension, oligoanuria, respiratory and heart impairment,

Objective

To analyze the adverse events observed during ATG infusion in patients undergoing SCT and treated with ATG for GVHD prophylaxis. The emergence of fever, chills, rash, pruritus, gastrointestinal symptoms, cephalea, peripheral edema, hypotension, oligoanuria, pulmonary edema, dyspnea, chest pain, arrhythmia and death during ATG infusion were collected. Premedication with corticosteroids, acetaminophen and antihistaminics, and the needs of additional treatment, oxygen support, diuretics and treatment discontinuations or switch were also analyzed.

Patients and Results

Sixty-five patients received ATG since 2004 to June 2012. Patients were grouped into three periods: first (2004-2006, 13 patients), second (2007-2009, 25 patients) and third (2010-2012, 27 patients). In all periods total median dose of ATG was 7.5 mg/kg. Fourty-nine patients (75%) developed infusion-associated reaction, being higher into the third period (46%, 72%, 93%, p< 0.01). The incidence of minor reactions as fever (90%), chills (57%), and skin reaction (35%) was similar in the three periods. Moderate reactions as peripheral edema (0%, 11%, 61%, p <0.001) and gastrointestinal symptoms (0%, 13%, 52%, p <0.002) were higher into the third period. Fifteen patients (31%) developed serious reactions and the majority accounted into the last period (29%, 11%, 48%, p=0.04). Dyspnea (25%) and pulmonary edema accounted for 9% of patients and both were higher into the third period (14%, 6%, 44%, p= 0.02) and (0%, 0%,26%, p=0.02). Although we did not reach statistical differences (p = 0.09) there were more cases of hypothension (0%, 6%, 26%) and oligoanuria (0%, 0%, 17%) in the last period. One patient developed chest pain associated with arrhythmia in the third period. None patient died during or shortly after ATG infusion. The needs of additional treatment, specially steroids (29%, 33%, 64%, p=0.09), oxygen (0%, 0%, 57%, p = 0.002) and diuretics (0%,0%,83%, p =0.001) were mostly used in the last period.

Conclusion

Since 2010, the incidence of moderate and severe ATG infusion-associated reactions in patients undergoing SCT is significantly more frequent than previously and in our opinion these facts may be confirmed in other studies.

Disclosures:

No relevant conflicts of interest to declare.
Risk Factor Analysis Of Idiopathic Pneumonia Syndrome After Allogeneic Hematopoietic Stem Cell Transplantation In Children
Authors: Sano Hirozumi , Kobayashi Ryoji , Iguchi Akihiro , Suzuki Daisuke , Kishimoto Kenji , Yasuda Kazue , Kobayashi Kunihiko
Published: October 2019

Idiopathic pneumonia syndrome (IPS) is a critical complication following allogeneic hematopoietic stem cell transplantation (HSCT); however, few reports have analyzed the risk factors for IPS in children. A total of 210 consecutive pediatric patients, including 131 boys and 79 girls, with various hematologic malignancies, aplastic anemia, or solid tumors who underwent allogeneic HSCT were analyzed to clarify the incidence and risk factors for IPS. Patient and transplantation characteristics after allogeneic HSCT were compared between patients with and without IPS. Cumulative incidence rates of IPS 120 days after allogeneic HSCT were 6.7% (14/210). Of 14 patients with IPS, 11 (78.6%) died after developing IPS. The presence of prior HSCT was more frequent in patients with IPS (IPS group) than in those without (non-IPS group) (35.7 vs 12.8%, respectively, P=0.018). The IPS group contained more patients with acute GVHD (grade II-IV) than the non-IPS group (50.0 vs 18.9%, respectively, P=0.006). The association of these two factors with IPS was further confirmed by multivariate analysis. We should be aware of these risk factors in patients who have undergone allogeneic HSCT. The rapid progression to respiratory failure and high mortality rate following the onset of IPS, despite advances in supportive care, require the development of new preventive measures and treatment modalities. Further preclinical and clinical studies are required to understand the pathogenesis of IPS and improve the prognosis of HSCT recipients.

Disclosures:

No relevant conflicts of interest to declare.
Immune Reconstitution In Fanconi Anemia Patients Following Allogeneic Bone Marrow Transplantation
Authors: Beltrame Miriam P , Malvezzi Mariester , Carmem Bonfim , Covas Dimas T , Orfao Alberto , Pasquini Ricardo
Published: October 2019

Background

Fanconi anemia is an autosomal recessive or X-linked genetic disorder characterized by bone marrow (BM) failure/aplasia. Failure of hematopoiesis results in depletion of the BM stem cell reservoir, which leads to severe anemia, neutropenia and thrombocytopenia, frequently requiring therapeutic interventions including hematopoietic stem cell transplantation (HSCT). Successful BMT requires reconstitution of normal immunity.

Methods

In the present study, we performed a detailed analysis of the distribution of peripheral blood subsets of T, B and NK lymphocytes in 23 patients with Fanconi anemia before and after BM transplantation (at days D+30, D+60 and D+100, D+180 D+270 and D+360). In parallel, we also compared the patients groups who received related and unrelated bone marrow, pre and one year after BMT.

Results

After transplantation, we found different kinetics of recovery for the distinct major lymphocyte subsets. NK cells were the first to recover, followed by cytotoxic CD8+ T-cells and B-cells, and finally also the CD4+ T-helper cells. Early recovery was at the expenses of memory cells which would therefore be potentially derived from the graft whereas, recent thymic emigrant (CD31+ CD45RA+) and naive CD4+ or CD8+ T-cells, rose only 6 months after HSCT, in the presence of immunosuppressive graft-vs-host disease (GVHD) prophylactic agents. While only slight differences were observed in the early recovery of cytotoxic CD8+ T-cells among cases receiving a graft from related vs. unrelated donors, cases suffering from GVHD displayed more marked differences vsother patients.

Conclusions

Overall, our results support the utility of post-transplant monitoring of peripheral blood lymphoid subsets, for improved monitoring and follow-up of Fanconi anemia patients undergoing BMT.

Disclosures:

No relevant conflicts of interest to declare.
Second Autologous Stem Cell Transplant As Salvage Therapy For Multiple Myeloma
Authors: Elemary Mohamed , Emara Mohamed , Sharma Ankur , Sarker Sabuj , Sabry Waleed , Stakiw Julie
Published: October 2019

Introduction

Therapeutic options for patients with multiple myeloma whose disease has relapsed after a prior autologous

SCT include novel agents, traditional chemotherapy or a second transplant, with no clear standard of care. Limited data are available regarding the value of salvage therapy with a second autologous SCT in patients who relapse after the first one, and the factors that determine the outcome of the second SCT.

We retrospectively reviewed our experience at Saskatoon Cancer Center with salvage autologous SCT for relapsed multiple myeloma.

Methods

Thirty three patients had received a salvage auto-SCT at our institution between February 2000 to February 2012.

Median age at second SCT was 60 years (range; 46-71), Median time to relapse after the first SCT was 32 months (range; 3-80). Median interval between the first and second transplant was 34 months (range; 4-85).

Re-induction therapy prior to second transplant contained combination with novel therapies (Bortezomib , lenalidomide or Thalidomide) in Thirteen patients ( 40 %) and the rest received conventional combination chemotherapies.

Median line of therapies before the second SCT was 1 (range 0-3) with 23 patients (70%) received less than 2 lines and 30% received more than 2 lines.

Results

Responses to second autologous SCT at day 100 showed CR in 21%, VGPR 30 %, PR 42% with ORR 93 %.

Non relapse mortality at day 100 after second transplant was 3 % (no= 1)

With a median follow up time of 24 months (range 1-99) from the salvage SCT, the median PFS was 27 months

(range 1-89) and the median overall survival (OS) was 36 months ( range 1-99)

Eleven patients had TTP inversion (PFS longer after the second transplant) with a median increase of 18 months , of note only two of them received novel agents for salvage, but 70 % required less than two lines prior to salvage SCT.

In univariate analysis, patients who had received < 2 lines of therapy prior to salvage SCT (23/33) had significantly higher median TTP of 31 and OS of 52 months, compared to 19 and 33 months for patients who had received ≥2 lines of therapy (10/33). (P = 0.04)

Patients who had relapsed more than 2 years post 1st SCT (18/33) had a significantly higher median TTP and OS of 27 and 39 months respectively compared to 22 and 24 months patients who had relapsed less or equal to 2 years (15/33) (P= 0.04)

In multivariate analysis, only response to salvage SCT > PR had an impact on TTP and OS; however it was not statistically significant.

Conclusion

Second salvage auto-SCT generally is safe and effective in patients with relapsed multiple myeloma. Patients with ≥2 prior lines of therapy and a TTP after initial transplant of ≤24 months are unlikely to benefit significantly. Salvage auto-SCT should therefore be considered for appropriate patients with relapsed multiple myeloma.

Disclosures:

No relevant conflicts of interest to declare.
Comparison Of Allogeneic Hematopoietic Cell Transplantation Versus Chemotherapy In Patients With Acute Myeloid Leukemia In First Remission
Authors: Lai Xiaoyu , Zhu Mingyu , Luo Yi , Tan Yamin , Zheng Weiyan , Zhu Yuanyuan , Shi Jimin , Huang He
Published: October 2019

Objective

To compare the effiency and safety of allogeneic hematopoietic stem cell transplantation versus chemotherapy in patients with acute myeloid leukemia in first remission

Methods

Clinical data of 225 patients who were diagnosed AML between Jan 1st 2006 to Dec 31 2011,getting CR1 after chemotherapy,of which 77 patients received allogeneic stem cell transplantation after CR1(SCT group) and 148 patients still received chemotherapy(CTx group).Follow up to Dec 31 2012,we evaluate the RFS and OS between SCT and CTx group

Results

Median follow up timeFSCT 34.00 monthsGCTx 25.50 months.The median CR period(months): SCT 33.00 vs CTx 22.50(p<0.01)G 3y OS: SCT 75.8% vs CTx 55.8%(p<0.001),both in intermediate and unfavourable karyotype group, SCT is better than CTx with statistical significance. 3y RFS: SCT 72.7% vs CTx 44.8%(p<0.001),both in intermediate and unfavourable karyotype group, SCT is better than CTx with statistical significance. Among the 148 patients in CTx group,79 died by the end of the follow up time,of which 31 died of TRM.In the SCT group, the TRM rate was 11/18,the TRM rate has no statistical significance between the two groups.

Conclusions

Allogeneic hematopoietic stem cell transplantation is safe and effective for AML-CR1 patients who are categorized into the intermediate or unfavourable group according to the SWOG criteria.

Disclosures:

No relevant conflicts of interest to declare.
Pre-Transplantation Assessment Of Mortality (PAM) Score Is a Poor Predictor For Survival In The Highest Risk Group When Used In T Cell Depleted Myeloablative Allogeneic Transplants
Authors: Kishore Bhuvan , Wiseman Daniel , Nikolousis Emmanouil , Lovell Richard , Milligan Donald , Holder Kathy , Bratby Lynn , Murthy Vidhya , Paneesha Shankaranarayana
Published: October 2019

Introduction

PAM score is a simple tool for predicting mortality risk in patients undergoing allogeneic bone marrow transplantation. Originally developed and validated at Fred Hutchinson Cancer Research Center, Seattle, this has recently been validated in 276 patients from Japan. We retrospectively evaluated this in our cohort of T deplete myeloablative allogeneic transplants as there are no published studies validating PAM score in T deplete myeloablative setting.

Results

After a median follow up of 63 months 51% of the patients are alive. The predicted mortality for category 2, 3 and 4 patients via PAM score was 28%, 48% and 28% respectively. This was concordant with the predicted mortality at 2yrs for category 2 and 3. Category 4 was not concordant (Chi-square test, P=0.0035).

Disclosures:

Milligan: Celgene: unrestricted educational grant Other.
Abnormal Expression Of Shelterin Is Associated With Short Telomere and Immune Disorder In Severe Aplastic Anemia
Authors: Shao Zonghong , Wang Ting , Fu Rong
Published: October 2019

Objective

To identify changes in telomere length and gene expression of shelterin (which is composed of six core components: TRF1, TRF2, POT1, TIN2, TPP1 and RAP1) in severe aplastic anemia(SAA). Looking for the reason why telomere getting short in SAA patients and the pathway that abnormal telomeres cause AA.

Methods

15 controls and 27 cases of SAA were enrolled in this study. There were 9 untreated and 18 recovering patients. Peripheral white blood cells(PWBCs)’ telomere length was tested by southern blot and gene expression of shelterin were detected by RT-PCR. Bone marrow mononuclear cells (BMMNC) from controls were cultured in different culture medium which were fetal calf serum only , SAA serum only, fetal calf serum containing TNF-α and fetal calf serum containing IFN-γ respectively. The apoptosis of these cells were detected by flowcytometry. The mRNA expression of POT1 were tested by RT-PCR , all the protein below including ATR, phosphorylated ATR, and phosphorylated ATM/ATR substrate were detected by western blot.

Results

Telomeres length of PWBCs were found significantly shorter in SAA untreated group (4.89±1.66)kb and recovering group (7.04± 1.47 )kb than control group (11.65±5.55)kb (P<0.05). Telomeres Length of PWBCs turned shortening in accordance with TH/S (CD4+Tcells/CD8+Tcells ratio) decreasing (r=0.593, p=0.007). The mRNA expression of POT1 decreased in SAA untreated group( 0.29(0.09-0.58)) than in recovering group( 0.78(0.22-2.69)) and controls (1.88(0.93-3.81)), (P<0.05). No differences about mRNA expression of TRF1、TRF2、TIN2、TPP1 and RAP1 were found among SAA untreated group, recovering group and controls in PWBCs. Undoubtedly, cells that cultured in SAA serum got more apoptosis(13.88±4.55) than that cultured in fetal calf serum(9.85±2.67)(P<0.05). The mRNA expression of POT1 was significantly declined in cells that from SAA patient uncultured group (0.45±0.29) , normal BMMNCs cultured by AA serum group (0.59±0.49) and IFN-γ group (0.40±0.35) than the cells cultured only by fetal calf serum group (1.19±0.62). ATR, phosphorylated ATR, and phosphorylated ATM/ATR substrate were found significantly increase in cells from AA serum group , TNF-α group and IFN-γ group than fetal calf serum group.

Conclusion

SAA patients have short PWBCs’ telomeres length which was in accordance with TH/S.TNF-α and IFN-γ which were found at high concentration in SAA decades before may be the effective component that can trigger apoptosis through POT1 and the pathway of ATM/ATR and eventually lead to SAA.

Disclosures:

No relevant conflicts of interest to declare.
Identification of MLL-Fusion/Myc⊣miR-26a/Mir-29a⊣Tet1 Signaling Circuit in MLL-Rearranged Leukemia
Authors: Huang Hao , Jiang Xi , Wang Jinhua , Li Yuanyuan , Chen Ping , Arnovitz Stephen , Li Shenglai , Wang Yungui , Weng Hengyou , Neilly Mary Elizabeth , Li Zejuan , Chen Jianjun
Published: October 2019

Approximately 10% of human acute leukemias are involved in chromosomal translocations between the mixed lineage leukemia (MLL) gene and over 50 partner genes. MLL-rearranged leukemias occur preferentially in infant and young children and are often associated with poor outcome. MicroRNAs (miRNAs) are an abundant class of small noncoding RNAs which repress gene expression and mRNA stability by base pairing with target mRNAs usually at the 3’-untranslated regions (UTRs). The ten-eleven translocation 1 (TET1), the founding member of the TET family of enzymes (TET1/2/3) that convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), was first identified in MLL-rearranged leukemia. But its definitive role in leukemia was unclear until our recent report published in PNAS (Huang H. et al. 2013). In contrast to the frequent repression and tumor-suppressor roles of the three TET genes observed in various cancers, we showed that TET1 is a direct target of MLL-fusion proteins and significantly up-regulated in MLL-rearranged leukemia, leading to a global increase of 5hmC level. Furthermore, Tet1 plays an indispensable oncogenic role in MLL-rearranged leukemia, through coordination with MLL-fusion proteins in regulating their critical co-targets including Hoxa/Meis1/Pbx3 genes. However, whether TET1 is also post-transcriptionally regulated by miRNAs in hematopoietic cells remains unknown. In the present report, through genome-wide miRNA expression profiling assays, we found that miR-26a and miR-29a were expressed at a significantly lower level in MLL-rearranged AML than in normal controls. The down-regulation of miR-26a and miR-29a is, at least in part, attributed to the transcriptional repression mediated by MLL-fusion proteins and MYC. Interestingly, both miR-26a and miR-29a target TET1 directly at the post-transcriptional level. More importantly, we showed that miR-26a or miR-29a significantly inhibited MLL-fusion-mediated cell transformation in vitro and leukemogenesis in vivo down regulating expression of Tet1 and its downstream target genes. Thus, our data suggest that the transcriptional repression of miR-26a and miR-29a is required for the aberrant overexpression and potent oncogenic role of TET1 in MLL-rearranged leukemia, and that miR-26a and miR-29a play important tumor-suppressor role in leukemogenesis.

Taken together, our data reveals a previously unappreciated signaling pathway involving the MLL-fusion/Myc⊣miR-26a/miR-29a⊣Tet1 circuit in MLL-rearranged leukemia. Our data not only provides novel insight into our understanding of the complex molecular mechanisms underlying the pathogenesis of MLL-rearranged leukemia, but also may lead to the development of novel, more effective therapeutic strategies to treat this type of dismal disease.

Disclosures

No relevant conflicts of interest to declare.
Recently Improved Results of Hematopoietic Cell Transplantation in Thalassemia Patients in Asia
Authors: Li Chunfu , Lee Vincent , Ha Shau Yin , Lin Hai Peng , Lee Anselm , Luo Chengjuan , Tan Poh-Lin , Tan Poh-Lin , Li Qi
Published: October 2019

Objective

Hematopoietic cell transplantation (HSCT) is not widely used for patients with b-thalassemia major (TM) so far because of transplant toxicities. Furthermore the tangible outcomes of contemporary HSCTs in Asia are unknown.

Methods

A newly founded consortium named the Viva-Asia BMT Group collected HSCT data retrospectively and investigated whether TM-HSCT outcomes had improved in recent years in Asia and whether an upper age limit can be determined for safe transplantation.

Results

From 1991 to 2012, 422 TM-HSCTs were performed among the 8 Asian centers; half (n=209) were before January 2009 (early cohort) and the other half (n=213) were performed thereafter (recent cohort). All major outcomes including overall survival (OS), TM-free survival (TFS), incidences of graft rejection (GR) and transplant-related mortality (TRM) improved significantly in the recent cohort (OS 93.4%, TFS 88.6%, GR 4.4% and TRM 6.6%) when compared with the earlier cohort (OS 84%, TFS 68.1%, GR 17.1% and TRM 16%). In the recent cohort, favorable OS, TFS, GR and TRM were observed with unrelated donors (n=168, 92.8%, 87.8%, 4.2% and 7.2%, respectively), with one-antigen mismatched parental donors (n=26,100%, 100%, 0% and 0%, respectively), and in patients younger than 10 years (n=173, 96%, 90.8%, 4.7% and 4.0%, respectively). TFS with unrelated cord blood (35.3%) was poor.

Conclusion

The excellent outcomes of contemporary TM-HSCT in general suggest that transplantation is a viable option for many Asian patients, particularly those younger than 10 years from areas with limited resources for chronic transfusion and iron chelation.

Figure 1A OS, TFS, GR and TRM in (A) the total 422 patients, (B) the recent cohort, and (C) the earlier cohort. Abbreviations: GR, graft rejection; OS, overall survival; TFS, thalassemia major-free survival; TRM, transplant-related mortality. Figure 1A. OS, TFS, GR and TRM in (A) the total 422 patients, (B) the recent cohort, and (C) the earlier cohort. Abbreviations: GR, graft rejection; OS, overall survival; TFS, thalassemia major-free survival; TRM, transplant-related mortality.

Figure 1B Figure 1B.

Figure 1C Figure 1C.

Disclosures

No relevant conflicts of interest to declare.
P-Selectin Expression and Platelet Function Are Developmentally Regulated
Authors: Stolla Massiel Chavez , Leyens Kathryn , Catherman Seana C , McGrath Kathleen E , Palis James
Published: October 2019

Platelets have numerous well-defined roles during adult hemostasis, however little is known about whether these functions are developmentally regulated. In the adult, P-selectin is constitutively expressed in megakaryocytes and localized to the membrane of alpha granules. Activation of platelets results in granule secretion and P-selectin surface exposure allowing for recruitment of leukocytes to sites of vascular injury and the formation of leukocyte-platelet aggregates. Here, we examined the expression and function of P-selectin in platelets during murine embryogenesis. Platelets were isolated from timed pregnant outbred-ICR mice at embryonic day 12.5 (E12.5), E15.5, postnatal day 1 (PN1), PN7, PN21, and were assayed for thrombin induced integrin activation and P-selectin translocation. While no significant differences were seen in the ability of embryonic platelets to be activated by thrombin, P-selectin surface expression after thrombin stimulation was significantly reduced in embryonic compared to adult platelets (E15.5 p=.0006, E12.5 p=.0004, PN1 p=.01, n=3, unpaired t-test). Surprisingly, P-selectin expression began to appear on the surface of activated platelets only after birth, approaching 50% and 75% of maternal expression at PN7 and PN21, respectively. No significant difference was seen in VEGF secretion after thrombin activation of E12.5, E15.5 and adult platelets (n=5), suggesting that the lack of P-selectin surface expression was not due to a loss of alpha granule secretion. To further characterize expression of P-selectin, real-time qPCR was performed on mRNA harvested from platelets at E12.5, E15.5, PN1 and adult stages. P-selectin transcript levels were significantly lower in embryonic and PN1 platelets, suggesting that P-selectin expression is transcriptionally regulated. Consistent with this concept, Imagestream analysis indicates that P-selectin protein is absent in megakaryocytes derived from the fetal liver. P-selectin expression on platelets is an important mediator of platelet-leukocyte interactions; therefore, we assayed the ability of platelets to bind to leukocytes in embryonic whole blood. Preliminary data suggest that embryonic platelets do not form leukocyte-platelet aggregates upon ex vivo stimulation with AYPGKF, a Par4 agonist. Taken together, our data indicate that P-selectin expression is developmentally regulated in primary mouse platelets. The absence of P-selectin expression in embryonic platelets correlates with an impaired ability to interact with leukocytes.

Disclosures

No relevant conflicts of interest to declare.
Role of the Thrombin-PAR-1 Pathway in Coxsackievirus Induced Hepatitis
Authors: Tatsumi Kohei , Antoniak Silvio , Mackman Nigel
Published: October 2019

Objective: Coxsackievirus B3 (CVB3) can infect different tissues including the heart and liver. Recently, we found that activation of the coagulation cascade and protease-activated receptor 1 (PAR-1) enhances toll-like receptor-3 (TLR3) mediated interferon-β (IFN-β) expression and protects mice from CVB3-induced myocarditis. Here, we investigated the role of PAR-1 in early anti-viral responses in mice and isolated hepatocytes.

Methods: Wild-type (WT) and PAR-1 deficient (PAR-1-/-) mice were infected with CVB3 intraperitoneally. The innate immune response, viral load, liver enzyme plasma levels, and inflammation levels were analyzed. Bone-marrow transplantation experiments with the combination of WT mice PAR-1-/- mice were performed to identify the cellular source of PAR-1 contributing to the innate immune response to CVB3. We also analyzed the effect of the direct thrombin inhibition with dabigatran etexilate on CVB3 hepatitis. In addition, we analyzed the effect of PAR-1 activation on TLR3-dependent interferon (IFN)-β expression in primary mouse hepatocytes and the human hepatocyte cell line PH5CH8 in vitro.

Results: PAR-1-/- mice exhibited a reduced early innate immune response in the liver at day 4 after infection, which was associated at later times (day 8) to higher viral titers in the liver, increased alanine transaminase plasma levels and more remarkable inflammation compared to control WT mice. Bone marrow transplantation experiments demonstrated that PAR-1 on non-hematopoietic played the major role in the innate immune response of CVB3 hepatitis. Stimulation of PAR-1 with either thrombin or agonist peptide on primary mouse hepatocytes and human PH5CH8 cells in vitro enhanced the antiviral response to dsRNA by increasing IFN-β and C-X-C motif chemokine 10 (CXCL10) expressions, supporting the results of in vivo experiments.

Conclusion: Our results suggest that activation of PAR-1 on hepatocytes enhances the innate immune response to CVB3 in the liver.

Disclosures

No relevant conflicts of interest to declare.
C1q-Binding HLA Antibodies Do Not Predict Platelet Transfusion Failure in TRAP Study Participant
Authors: Jackman Rachael P. , Bolgiano Douglas , Lebedeva Mila , Slichter Sherrill J. , Norris Philip J.
Published: October 2019

Introduction: In the Trial to Reduce Alloimmunization to Platelets (TRAP) study, 101 of the 530 subjects became clinically refractory (CR) to platelet transfusions in the absence of detectable antibodies against HLA as measured by the lymphocytotoxicity assay (LCA). Using more sensitive bead-based detection methods we have previously demonstrated that while many of these LCA- patients do have anti-HLA antibodies, that these low to moderate level antibodies do not predict refractoriness. In addition to being less sensitive then bead based methods, the LCA screen only detects complement-binding antibodies. As these antibodies could be important for platelet rejection, we assessed if previously undetected complement-binding antibodies could account for some of the refractoriness seen in LCA- patients.

Methods: 169 LCA- (69 CR, 100 non-CR) and 20 LCA+ (10 CR, 10 non-CR) subjects were selected from the TRAP study. Anti-class I HLA IgG and C1q binding antibodies were measured in serum or plasma using two different multi-analyte, semi-quantitative, bead-based fluorescent antibody detection assays: the LabScreen mixed Luminex assay, and the LabScreen single antigen class I assay with or without added EDTA (One Lambda). Groups were compared using an unpaired t-test, a=0.05, and correlation between variables was also assessed.

Results: New measurements of anti-class I HLA IgG antibodies reliably reproduced earlier data with a strong correlation between the old and new measurements (R2=0.9736, p<0.0001). While some of the LCA- subjects did have detectable C1q-binding anti-class I HLA antibodies, and some LCA+ subjects did not, levels of these antibodies were significantly higher among LCA+ subjects (p<0.0001). Levels of C1q-binding anti-class I HLA antibodies were not significantly different between CR and non-CR among either the LCA- or LCA+ subjects.

Conclusions: While complement-binding anti-class I HLA antibody levels were higher in the LCA+ subjects, higher levels of these antibodies were not seen in CR LCA+ patients as compared with non-CR LCA+ patients. Complement-binding anti-class I HLA antibodies do not account for refractoriness seen among the LCA- TRAP subjects. This work confirms that low to mid level anti-class I antibodies do not drive refractoriness to platelets, and suggests that antibody-independent mechanisms cause refractoriness in patients lacking higher levels of anti-HLA antibodies.

Disclosures

No relevant conflicts of interest to declare.
Lincrna Hotset Regulates Hox Gene Transcription and Promotes Early Hematopoietic Fates
Authors: Deng Changwang , Li Ying , Tusi Besabeh , Jian Wei , Patel Bhavita , Li Yangqiu , Bungert Jorg , Zhou Lei , Qiu Yi , Huang Suming
Published: October 2019

Mammalian genomes encode tens of thousands of long intergenic noncoding RNAs (lincRNAs). Accumulated evidence suggests that many of lincRNAs are expressed in a development- or tissue-specific manner. However, it remains largely unknown how lincRNAs reprogram lineage-specific gene expression and regulate lineage-specific differentiation processes during early embryonic development. It is also important to identify specific lincRNA(s) that is involved in early hematopoietic lineage formation and differentiation. Here, we reported a HoxB locus-associated lincRNA HOTSET that is conservatively expressed in both mouse and human hematopoietic stem and progenitor cells (HS/PCs). During embryonic development, HOTSET RNA is dramatically induced upon embryoid body (EB) hematopoietic differentiation. Expression of HOTSET RNA is required for development of the mesoderm-derived Flk1+ bipotential precursors of blood and endothelium lineages and CD41+/c-Kit+ hematopoietic stem and progenitor cells. We demonstrated that HOTSET RNA directly interacts with the SET domains of Setd1a and MLL1 histone methyltransferases in a sense-strand dependent manner. HOTSET RNA directly binds to the HoxB1-6 gene promoters and recruits the Setd1a/MLL1 complexes to the anterior HoxB locus upon differentiation. Furthermore, HOTSET RNA mediated H3K4 methylation is essential for long-range chromatin loops that bring anterior HoxB genes into a close proximity with HOTSET RNA locus and for subsequent activation of anterior HoxB gene expression. In addition, knockdown of HOTSET RNA disrupts the recruitment of the Setd1a/MLL1 complexes, H3K4me3 levels, the three-dimensional chromatin architecture, and HoxB gene transcription at the HoxB gene cluster. Depletion of HOTSET RNA also impairs differentiation of the CD41+/c-Kit+ HS/PC population and hematopoietic transcription factor and signaling networks required for early hematopoietic differentiation. Importantly, re-expression of HoxB2-4 genes in the HOTSET-depleted embryoid bodies rescues the expression of core hematopoietic transcription factors as well as the Flk1+ mesoderm-derived precursors and CD41+/c-Kit+ HS/PCs that undergo hematopoietic differentiation. Thus, HOTSET plays an important role in early hematopoietic lineage commitment by shaping the three-dimensional chromatin landscape in the HoxB locus to activate anterior HoxB genes that subsequently modulate lineage-specific transcription networks during hematopoietic development.

Disclosures

No relevant conflicts of interest to declare.
Ki-67 Is a Strong Predictor for Central Nervous System Relapse in Patients with Mantle Cell Lymphoma (MCL)
Authors: Chihara Dai , Asano Naoko , Ken Ohmachi , Nishikori Momoko , Okamoto Masataka , Sawa Masashi , Sakai Rika , Okoshi Yasushi , Tsukamoto Norifumi , Yakushijin Yoshihiro , Nakamura Shigeo , Kinoshita Tomohiro , Ogura Michinori , Suzuki Ritsuro
Published: October 2019

Abstract

Background: CNS relapse is uncommon but challenging complication in patients with mantle cell lymphoma (MCL). Survival after CNS relapse is extremely poor that identification of high risk population is therefore critical in whom prophylactic chemotherapy may play a role.

Patients and Methods: A total of 405 patients (median age, 66 years; range 22-85) with MCL newly diagnosed between 1994 and 2012 at 48 institutions in Japan were analyzed.Pathological specimens were centrally reviewed in all patients. We evaluated risk factors for CNS relapse in patients with MCL using competing risk regression analysis. Patients were excluded if they had evidences of CNS involvement at initial diagnosis. Overall, 81% of the patients received rituximab containing regimen with 222 patients received CHOP, 133 patients received high-dose cytarabine containing regimen and 50 patients received other regimen such as fludarabine. At a median follow up duration of 40.4 months, 25 patients (6.2%) experienced CNS relapse. Five patients presented with brain parenchymal mass, 13 patients presented with leptomeningeal disease, and 7 patients presented with both. The median time from initial diagnosis to CNS relapse was 18.5 months. Two-year cumulative incidence of CNS relapse was 4.7% (95%CI: 2.8-7.3). No difference was seen in the incidence of CNS relapse between the treatment with or without rituximab. Univariate analysis revealed blastoid or pleomoriphic variant, Ki-67 ≥ 30, serum total protein < 6.0g/dl, leukemic presentation and high risk group in simplified-MIPI at diagnosis as significant risk factors for CNS relapse. Within these five factors, Ki-67 was the strongest predictive factor for CNS relapse with hazard ration of 8.7 (95%CI: 3.4-22.2). Two-year cumulative incidence of CNS relapse in patients with Ki-67 ≥ 30 was 25.4% (95%CI: 13.5-39.1), while that in patients with Ki-67 < 30 was 1.5% (95%CI: 0.2-2.9) (Figure). Ki-67 ≥ 30 was a significant risk factor for CNS relapse both in patients who received CHOP and hyper-CVAD/MA. Survival after CNS relapse was dismal with median survival time of 5.7 months.

Summary: We identified four risk factors for CNS relapse in patients with MCL. Within these factors, Ki-67 ≥ 30 is the strongest predictive factor with 2-year cumulative incidence of 25.4%. Evaluation for CNS involvement at the diagnosis and assessment for value of prophylactic IT chemotherapy is mandatory in patients with Ki-67 ≥ 30.

Figure 1: Cumulative incidence of CNS relapses by Ki-67 Figure 1:. Cumulative incidence of CNS relapses by Ki-67

Disclosures

No relevant conflicts of interest to declare.