ALBERT

Description: Recessive congenital methemoglobinemia due to nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase (b5R) deficiency is classified into 2 clinical types: type 1 (erythrocyte type) and type 2 (generalized type). We found a Chinese family with type 1 recessive congenital methemoglobinemia, the patients from which were diagnosed according to clinical symptoms and b5R enzyme activity in the blood cells. To learn the molecular basis of type 1 recessive congenital methemoglobinemia in this Chinese family, we isolated total RNA from the peripheral leukocytes of the propositus and b5R complementary DNA (cDNA) by reverse transcription– polymerase chain reaction (RT-PCR). The coding region of the b5R cDNA was analyzed by sequencing the cloned PCR products. The results showed that the propositus was homozygous for a G→A transition at codon 203 in exon 7, changing a cysteine to a tyrosine (Cys203Tyr). To characterize the mutant enzyme, both glutathione S-transferase (GST)-fused wild-type b5R and GST-fused mutant Cys203Tyr b5R were expressed in Escherichia coli and affinity purified. The results showed that the catalytic activity of the enzyme was not much affected by this amino acid substitution, but the mutant enzyme exhibited decreased heat stability and increased susceptibility to trypsin. These properties of the mutant enzyme would account for the restricted b5R deficiency and mild clinical manifestations of these type 1 patients. The finding of this novel mutation makes codon 203 the only position within the b5R gene at which more than 1 mutation has been found.

Description: B-cell receptor (BCR) diversity is achieved centrally by rearrangement of Variable, Diversity, and Joining genes, and peripherally by somatic hypermutation and class-switching of the rearranged genes. Peripheral B-cell populations are subject to both negative and positive selection events in the course of their development that have the potential to shape the BCR repertoire. The origin of IgM+IgD+CD27+ (IgM memory) cells is controversial. It has been suggested that they may be a prediversified, antigen-independent, population of cells or that they are a population of cells that develop in response to T-independent antigens. Most recently, it was suggested that the majority of IgM memory cells are directly related to switched memory cells and are early emigrants from the germinal center reaction. Advances in sequencing technology have enabled us to undertake large scale IGH repertoire analysis of transitional, naive, IgM memory and switched memory B-cell populations. We find that the memory B-cell repertoires differ from the transitional and naive repertoires, and that the IgM memory repertoire is distinct from that of class-switched memory. Thus we conclude that a large proportion of IgM memory cells develop in response to different stimuli than for class-switched memory cell development.

Description: Multiple myeloma (MM) is the most frequently occurring bone cancer and is characterized by malignant antibody-producing cell accumulation in bone marrow (BM). MM is still incurable, and the disease management is complicated by crosstalk between MM cells and the BM microenvironment. Why MM cells predominantly locate in bone is not well understood. The process by which MM cells are recruited into BM and reside in bone for colonization is called MM BM homing. BM homing is also critical for MM metastasis to distal BM sites. Therefore, MM BM homing is an active process throughout the disease pathogenesis. Here for the first time, we report that macrophage migration inhibitory factor (MIF) regulates MM BM homing via a mechanism that involves MM adhesion in the BM microenvironment. More importantly, we also show that MIF might be a promising target for MM treatment. MIF is an inflammatory cytokine, secreted by various human cell types. Our results here showed that BM biopsies from MM patients had significantly higher MIF expression, compared with that from healthy donors as determined by both immunohistochemistry of BM biopsies and ELISA of BM aspirates (P

Description: BACKGROUND: This study was to evaluate the efficacy and safety of chidamide monotherapy, which is a new histone deacetylase inhibitor (HDAci) of the benzamide class, in relapsed or refractory Angioimmunoblastic T cell lymphoma (AITL), to investigate its genomic expression signatures as well as the mechanisms of chidamide's anti-lymphoma effect and its resistance. METHODS: Two cases with relapsed or refractory AITL were treated with chidamide. We performed a repeated biopsy on relapsed lymphomas and did whole genome next-generation sequencing (NGS) testing on drug -resistant tumor samples. RESULTS: The first patient is a 54-year-old man presented with stage Ⅳ AITL. He underwent autologous stem cell transplantation in his first complete remission (CR) but relapsed 7 months later. In view of resistance to multiple lines of chemotherapy and poor performance status, chidamide was adaministered orally at a standard dose of 30mg twice a week. Pulmonary lesions regressed quickly and a second CR was achieved. Adverse events included grade 2 cytopenias, diarrhea, and reversible QT interval prolongation. The disease free survival was 6 months and AITL relapsed again 4 months ago. He responded to low-dose chidamide combined with lenalidomide and dexamethasone and remains well. Formalin-fixed, paraffin-embeded tumor tissues collected at first relapse were tackled for whole-genome sequencing. The other patient is a 62-year-old woman who had stage Ⅲ AITL. Disease progressed after two cycles of combined chemotherapy, thereafter a standard dose of chidamide monotherapy was initiated. With well tolerability, an unconfirmed CR was achieved and lasted for nearly 3 months. She is still alive but remains refractory to various salvage therapeutics, including chemotherapies, arsenic trioxide, thalidomide, and pralatrexate. A rebiopsy was perferomed and the histopathological findings confirmed the relapse of AITL, associated with Epstein-barr virus infection. Fresh tumor tissues were sent for whole-genome sequencing. In both cases, NGS testing identified mutations of RHOA gene, epigenetic regulators TET2, IDH1, and DNMT3A, as well as CD28. CONCLUSIONS: Chidamide, a low nanomolar inhibitor of HDAC1, 2, 3, and 10, was approved in China for the management of relapsed and/or refractory peripheral T cell lymphoma. It's reported that patients with AITL tended to have higher response rates and more durable responses to chidamide treatment. Our report showed single-agent chidamide is a reasonable approach to treat the formidable disease but seemed difficult to achieve a sustained remission. Various genetic, epigenetic, and immune alterations involve in the pathogensis of AITL, which provide targets for chidamide therapy. High-throughput sequencing approach is very helpful to clarify the mechanisms. Disclosures No relevant conflicts of interest to declare.

Description: Objective The purposes of this study is to investigate the expression of Pim-1 and Pim-2 on macrophages in multiple myeloma (MM) patients; investigate the relationship between co-expression of Pim-1, Pim2 in macrophages and early treatment response and prognosis; investigate the expression of PD-1 and PD-L1 in multiple myeloma; and analyze correlation between the expression of PD-1 and PD-L1 and early treatment response and prognosis, providing preliminary therapeutic evidence for the novel treatment in multiple myeloma. Methods Clinical data and bone marrow biopsy sample of108 patients were selected with newly diagnosed multiple myeloma at West China Hospital of Sichuan University from 2009 to 2014 were collected. Patients that were included were followed up until May 2017. Opal multi-labeling immunohistochemistry of bone marrow was performed, and macrophages were labeled with anti-CD68 antibody in order to detect co-expression of P-im1, P-im2 and macrophages. They were divided into high-expression and low-expression groups according to the degree of their co-expression. Meanwhile detect the expression of PD-1, PD-L1 in MM and they were divided into positive and negative groups. The relationship between the different expression levels of Pim-1 and Pim-2 in macrophages、PD-1、PD-L1 and the early treatment response and prognosis of multiple myeloma were analyzed. The Kaplan-Meier method was used to analyze the influence on disease progression and overall survival in MM patients. The Cox proportional hazards model was used as multivariate analysis used to explore independent risk factors affecting the prognosis of MM patients. Results 1.The median PFS value in high CD68+Pim-1 co-expression group is significantly lower than that of the low expression group(14.0 months vs 24.2 months, Logrank, P=0.0314); the Cox proportional hazards model reveals that the risk of disease progression in high expression of CD68+Pim-1 group is significantly higher than that of the low expression group(risk ratio, 2.22; P=0.04 )Patients with high CD68+Pim-1 expression showed the median survival time is significantly lower than that of the low infiltration group (12.7months vs 37.9months, Logrank, P=0.005); the Cox proportional hazards model reveals that the risk of disease progression in high expression of CD68+Pim-1 group is significantly higher than that of the lower expression group(risk ratio, 4.21; P=0.001 )As for the bone marrow high CD68+Pim-1 expression group ,the median survival time is significantly lower than that of the low infiltration group (18.3 months vs 49.5months, Logrank, P=0.0044); the Cox proportional hazards model reveals that the mortality riskin high expression of CD68+Pim-1 group is significantly higher than that of the lower expression group(risk ratio, 3.64; P=0.01 ).Patients with PD-1 low expression group in bone marrow showed greater response (Complete response/Partial response), while the PD-1 high expression group showed lower response (P=0.013). Conclusion The expression extent of Pim-1 and pim-2 with macrophages in bone marrow are associated with clinical prognosis. The expression extent of pim-2 in MM tumor-associated macrophages display a strong negative correlation to PFS values and the overall survival. The expression extent of pim-1 in MM tumor-associated macrophages display a strong negative correlation to overall survival. Pim-1 and pim-2 are prognostic factors of multiple myeloma. There is a strong negative correlation between expression of PD-1 of bone marrow and the early treatment response. Since the expression degree of PD-1 showed different prognosis in solid tumors and hematological cancer. The evaluation requires combined with other biological indicators Disclosures No relevant conflicts of interest to declare.

Description: Background and Objective: There are 3 members in Pim family, Pim-1, Pim-2 and Pim-3. They are serine/threonine kinase coding proto-oncogene. It is reported that Pim-1 plays a role in solid tumor, leukemia and polycythemia vera, et al. Pim-3, as a newly cloned oncogene has discovered to functioning in hepatic carcinoma, pancreatic cancer, et al. We are trying to find out the roles of Pim1 in acute myeloid leukemia. Methods: 1 Evaluate the expressions of Pim family genes in acute myeloid leukemia patients and analysis the profile of Pim expressions with clinical characteristics. 2 Up-regulating the expression of Pim1 in AML cell lines by transient transfection or long-term infection through GFP-expressing plasmids and lenti-virus system and analyze the proliferation, apoptosis and chemotaxis features of the transfected AML cell lines. Results: 1 Our investigation showed that Pim-1 is up-regulated in around 15% of acute myeloid leukemia (AML) patients. 2 As shown in growth curves and apoptosis assays, over expression of Pim-1induces growth up-regulation and anti-apoptosis. We hypothesized that phenomenon could be originated from the enhanced expression of c-myc, cyclin D1 and Bad phosphorylation shown in western blotting analysis. 3 Our chemotaxis assay and bone marrow stromal cell co-culture model demonstrated that overexpression of Pim-1can enhance the AML cells chemotactic movement toward SDF-1¦Á, with calcium influx increment and phosphorylation of CXCR4. 4 Flow cytometry analysis and confocal immunofluorescence observation demonstrated the up-regulated CXCR4 expression and internalization induced by SDF-1¦Á. 5 We also checked the angiogenesis and adhesion molecule during the process but did not show any contribution. Conclusion: Pim-1, beyond as an oncogene, can promote growth or anti-apoptosis of AML cells, can interact with microenviroment through SDF-1¦Á-CXCR4 axis. The interplay between AML cells and microenviroment mediated by Pim-1 can make sense in AML target therapy and make a good adjunctive for transplantation conditioning regimen. Figure 1. Expression of Pim1 in AML patients and control Figure 1. Expression of Pim1 in AML patients and control Disclosures No relevant conflicts of interest to declare.

Description: Objective: The purpose of this study is to investigate the relationship between the infiltration of tumor associated macrophages (TAMs) and the disease risk stratification and survival of patients with myelodysplastic syndrome (MDS) and to explore the role of TAMs in the clinical prognosis. Methods: We retrospectively collected and analyzed 115 patients initially diagnosed wih myelodysplastic syndromes from January, 2010 to July, 2017 in West China Hospital of Sichuan University. Both bone marrow biopsy specimens and clinical data of the patients enrolled were collected. All patients were assessed prognosis by international prognostic scoring system (IPSS). We quantified the involvement of macrophage (MΦ), alternatively activated macrophage (M2 MΦ) and classic activated macrophage (M1 MΦ) in bone marrow specimen by staining with anti-CD68 monoclonal antibody, anti-CD163 monoclonal antibody, and anti-iNOS monoclonal antibody respectively. Log-rank test was used to evaluate the difference of overall survival (OS) among different subgroups. Logistic regression was used to evaluate the effect of clinical parameters on patients' OS. Cox proportional-hazards models were used to estimate the independent risk factors influencing the prognosis of patients. Results: 1 In the high risk group of MDS, the composition of CD163+MΦ was higher than that of the low risk group(p 〈 0.001). In the low risk group of MDS, the composition of iNOS+ MΦ was higher than that of the group with high risk(p 〈 0.001). 2 The median survival time and 3-year survival rate in the high CD163+MΦinfiltration group were significantly lower than those in the low infiltration group (13 months vs 43 months, 27% vs 64%, Log-rank test, P

Description: Background T-cell large granular lymphocytic leukemia (T-LGLL) is a rare lymphoproliferative disorder of cytotoxic T cells (CTLs) and often associated with autoimmune disorders. The signal transducer and activator of transcription 3 (STAT3) is an oncogene, and its activation plays a key role in cell signaling transduction pathways in many types of cancer. The aim of the current study was to analyze the characteristics of T-LGLL. Methods We did this by determining the mutation status of STAT3 in 28 patients presenting with T-LGLL and evaluating STAT3 status in association with serum level of lacticdehydrogenase (LDH) and β2-microglobulin (β2-MG). Flow cytometric analysis for immunophenotype and TCR variable β-chain (Vβ) was performed in the patients. Results FC-Vβ analysis was performed in 26 patients, and 22 (84.6%) patients had a restricted Vβ reactivity pattern, with predominance of a single Vβ mAb reactivity. There was no significant difference between serum LDH levels, gender, age or symptoms at diagnosis (P=0.062), lymphocytosis, anemia (P=0.057), thrombocytopenia, splenomegaly, LGL count or STAT3 mutation status. However, high β2-MG levels (P=0.005), neutropenia (P=0.018) and pure red blood cell aplasia (PRCA) (P=0.001) all displayed a significant association with STAT3 mutations. In univariate analysis, treatment-free survival (TFS) was affected by STAT3 mutation status (P=0.008) and β2-MG (P=0.006). In multivariate analysis, only anemia (P

Description: 【Introduction 】There is ongoing unmet need for effective therapies in Mayo 2004 stage II-III amyloid light-chain (AL) amyloidosis patients, who undergo early death due to cardiac dysfunction. Lately, in vitro studies demonstrated that doxycycline could induce disruption of fibril formation in transgenic mouse model of AL amyloidosis. Matched case-control study of standard chemotherapy with or without doxycycline confirmed higher hematological response, cardiac responses and superior survival with doxycycline in AL patients. However, the possible advantage of doxycycline on lower early mortality and better long-term survival has not been evaluated in a randomized controlled clinical trial. We designed a randomized unblinded controlled study to investigate the efficacy and safety of co-administration of oral doxycycline with bortezomib-cyclophosphamide-dexamethasone (BCD) regimen in treatment-naïve AL amyloidosis patients with Mayo 2004 stage II-III disease. 【Methods 】The randomized unblinded controlled study took place in 12 hospitals in China. Eligible participants were adults with a confirmed diagnosis of AL amyloidosis, whose Mayo 2004 stage were II or III. Enrolled patients were randomly allocated to receive either doxycycline combined with BCD or BCD alone as initial treatment. We chose stratified blocked randomization (block size of 4) to ensure Mayo stage II and III were evenly distributed between doxycycline group and control group. For both two groups, patients will receive 1.3mg/m2of subcutaneous bortezomib and 40mg of oral or intravenous dexamethasone on days 1, 8, 15 and 22, and 300mg/m2oral or intravenous cyclophosphamide on days 1, 8 and 15 of a 35-day cycle. This process was repeated for 9 cycles. Doxycycline was given orally 100mg twice daily for the experimental group. The primary endpoint is progression-free survival. Secondary endpoints include overall survival, adverse events, hematological response, organ response and safety of treatment. This trial has been registered with ClinicalTrials.gov (number NCT03401372) and recruitment and follow-up are ongoing. We planned to enroll a total of 140 participants. 【Results 】Between April 21st, 2018 and June 30th, 2019, 111 patients were enrolled and randomly assigned to receive doxycycline plus BCD (n=56) or BCD alone (n=55) (Figure 1). The baseline characteristics were shown in Table 1. The median age was 61 (range, 41-78) years with a male: female ratio of 1.64:1. Mayo 2004 stage II disease was present in 28 patients in the control group and 29 patients in the doxycycline group. Mayo 2004 stage III disease was present in 27 patients in the control group and 27 patients in the doxycycline group. The median cTnI was 0.10 (range, 0-1.92) μg/L, NT-proBNP 3647 (range, 271-20507) pg/mL, and dFLC 205.30 (50.28-791.90) mg/L, with no significant difference between either group. Organ involvement included the heart (100%), kidney (61.3%), liver (14.4%), peripheral nerves (10.8%) and gastrointestinal tract (5.4%). The percentage of hepatic involvement and 24-hour urine protein were higher in the doxycycline group. The median duration of doxycycline was 5.9 months. Only one patient discontinued doxycycline due to toxicity (Grade 2 rash). Till now, the median follow-up time was 6.1 months and no patients were lost to follow-up. Fourteen patients have completed 9 cycles of chemotherapy. In total, 22 patients died and disease progression occurred in 3 patients. Two patients discontinued treatment due to withdrawal of consent and one of them proceeded to autologous stem cell transplantation. Three patients discontinued study drug owing to unacceptable diarrhea and received second-line treatment based on ixazomib or melphalan afterwards. The grade 3/4 adverse effects were developed in 8 patients (1 infection, 1 mucositis and 6 diarrhea) in the control group and 6 patients (1 infection, 1 arrhythmia, 1 kidney dysfunction and 3 diarrhea) in the doxycycline group. 【Conclusions 】Our data suggested that addition of doxycycline to standard bortezomib-based chemotherapy was an tolerable regimen for treating patients with AL amyloidosis. If this protocol could significantly improve survival and organ response needs to be confirmed with further follow-up. Disclosures No relevant conflicts of interest to declare.

Description: Abstract 4243 [Background] Imatinib combined with intensive chemotherapy protocol markedly has markedly improved the prognosis of patients with Philadelphia chromosome-positive acute lymphocytic leukemia (Ph+ALL), and has become the standard therapy for this disease. Based on experience from patients with chronic myelogenous leukemia in blast crisis or accelerated phase, this highly specific tyrosine kinase inhibitor was given 600mg or 800mg daily in most clinical trials. However, some pilot study and case report implied that either lower dose of imatinib or less intensive chemotherapy could also achieve a satisfying remission rate. We carried out this pilot study to testify whether a lower dose of imatinib and less intensive chemotherapy could generate similar outcome, especially for patient who are unwilling to or unsuitable for allogeneic hematopoietic stem cell transplantation. [Method] Thirty six patients with de novo Ph+ALL were enrolled between Dec-2008 and Dec-2010. All patients received imatinib 400mg daily, vindesine 4 mg weekly and dexamethasone 10 mg/m2/day for 4 days per week as induction therapy. After complete remission, these patients received 3 courses chemotherapy of protocols adapted from China Acute Lymphocytic Leukemia Group (CALLG) as intensification. Those who were unwilling to receive or unsuitable for allo-HSCT received maintenance therapy with imatinib 400mg daily with chemotherapy by vindesine 4 mg on D1 and D11, dexamethasone 10mg/m2/day on D1-5 and D11-15 with or without interferon-α 3 million unit every other day. Patients over 55 year old skipped the intensification therapy. The maintenance chemotherapy was given once a month in the first year, once per 2 months in the second year, and once per 3 months in the third year. Sixteen cycles of intrathecal chemotherapy with cytarabine and dexamethasone +/− methotrexate was scheduled for central nervous system leukemia (CNSL) prophylaxis. [Result] Thirty six patients were enrolled, and the median age of this group of patients was 33.5 years (shown in table 1). All but one patients (97.2%) achieved complete remission after 4 weeks of induction therapy. One patient was loss of follow-up and one patient quit from this study because of severe hepatic dysfunction thought to be caused by imatinib. Three patients (8.3%) died of infections (pneumonia or sepsis) within intensification cycles. Three (8.3%) patients received allo-HSCT either from a sibling or an unrelated donor at CR1 after 3–4 courses of intensification therapy. The median time of follow-up was 8 months. The median overall survival was were 22.1 (shown in figure 1A.). For patients who received imatinib and chemotherapy only, the median overall survival was 20.4 months (shown in figure 1B). Although there was no evidence for CNSL at diagnosis in all patient, four (11.1%) patients had CNS relapse and three died despite of regular CNSL prophylaxis. [Conclusion] In this pilot study, our data showed that imatinib combined with less intensive chemotherapy could also achieve a over 90% remission rate in patients with de novo Ph+ALL. With the short time of follow-up, the long term effect of this strategy on survival and relapse can not determined yet, and a prospective randomized study is warranted. With reduced chemotherapy intensity, a more intensive protocol for CNS prophylaxis or new generation of TKI (e.g. dasatinib) with higher blood-brain barrier permeability may be considered. Disclosures: No relevant conflicts of interest to declare.