bluuebunny/crossref_metadata_2025 huggingface dataset:
Tissue Transglutaminase Regulates Steroid Resistance in Acute Lymphoblastic Leukemia Via Nuclear Factor-Kappa B Related Signaling Pathways
Authors: Jung Hyun Joo , Han Eunhee , Park Jun Eun
Published: October 2019

Steroid resistance is lethal to the patients with acute lymphoblastic leukemia (ALL). To improve survival for steroid-resistant ALL patients, it is necessary to develop innovative therapeutic strategies to overcome steroid resistance. Tissue transglutaminase (TG2) is an intracellular calcium-dependent protein cross-linking enzyme reported to be over-expressed in various metastatic or chemotherapy-resistant cancer cells including lymphoma cells. Chronic expression of TG2 constitutively activates nuclear factor kappa B (NF-kappaB) and it is directed linked to NF-kappaB-related signaling networks including hypoxia-inducible factor-1 (HIF-1), Zeb, Snail, or Twist that influence drug resistance or metastasis in inflammatory or cancer cells. In the present study, we used biochemical and molecular methodologies to demonstrate that steroid resistance was associated with TG2-regulated signaling pathways including NF-kappaB and its downstream transcriptional factors in steroid-resistant ALL. We generated steroid-adapted subclones of ALL cell lines that were extremely more resistant to steroid than the parent cells. We found that steroid-resistant ALL cells expressed elevated levels of TG2 and the modification of TG2 activities altered NF-kappaB expression in this cells. TG2-related NF-kappaB activation modulated the expression of HIF-1 and NF-kappaB-targeted genes such as Zeb, Snail, and Twist in steroid-resistant ALL cells. Also, TG2 inhibition improved the cytotoxicity of steroid in steroid-resistant ALL cells. This is the first study to show the link between TG2, NF-kappaB, its downstream signaling networks, and steroid resistance in ALL. TG2 inhibition could be used as an alternative target to overcome steroid resistance in ALL. Furthermore, TG2 and HIF-1 expression could serve as new biomarkers of steroid resistance evolution or cancer recurrence in ALL.

Disclosures

No relevant conflicts of interest to declare.
FLAG-IDA As First Line Induction Treatment for Children De Novo AML
Authors: Feng Xiaoqin , Li Chunfu , He Lan
Published: October 2019

Objective: The complete remission after induction therapy is very important for the prognosis of AML. Fludarabine, cytarabine, granulocyte colony-stimulating factor (G-CSF), and idarubicin (FLAG-IDA) regimen has been proven to be an effective chemotherapy for relapsed or refractory acute myeloid leukemia. The aim of this study was to evaluate complete remission rate and toxicity in children with de novo acute myeloid leukemia (none APL) who received the FLAG-IDA regimen as induction therapy.

Method: Between March 2014 and July 20015, 14 children with de novo acute myeloid leukemia (none APL) were received FLAG-IDA regimen as first line induction treatment in our center. The regimen including: Fludarabine 30 mg/(m2.d), PI 0.5hr, qd, d2-6;

Ara-C 2g/(m2.d), PI 3hr, d2-6; Ida (Idarubicin) mg/(m2.d), PI 1hr, qd, d4-6; G-CSF 5μg/(Kg.d), s.c./i.v. qd,d1-7.

Of the 14 children, age 1-13 years old (median age 7 years old), including 2 (14.3%) children with favorable gene, 4 (28.6%) children with high risk gene. 3(21.4%) children received 1 cycle, 11 (78.6%) received 2 cycles of FLAG-IDA regimen. The CR rate and toxicity in total 25 cycles were evaluated.

Result: After 25 cycles of FLAG-IDA regimen, only 1 child (7.1%) did not get CR, 13/14 (92.9%) got CR after 1 or 2 cycles of FLAG-IDA induction treatment. In 25 FLAG-IDA cycles, the neutropenic time was from 13-43 days (mean 24.8 days). In the induction period, 2(14.3%) children suffered sepsis, 3 children (21.4%) had proven invasive fungal infection. Of 14 children, 2 children(14.3%) combined with cutaneous anaphylaxis, 2 children combined with transient fever after venous transfusion of chemicals. None obvious cardiac toxicity (arrhythmia or heart failure) was proved. One child died of ARDS in the neutropenic period after 2nd FLAG-IDA cycle. Of 14 children, 12 children (85.7%) got continues CR with the follow up 1-19 months (median 8 months).

Discussion: Our primary study showed quite high CR rate combined with quite toxicity but can be tolerated using the FLAG-IDA regimen as first line induction treatment. Comprehensive supportive care should be given during the induction therapy. The LFS and OS need to be feedback after long time follow up.

Disclosures

No relevant conflicts of interest to declare.
Arsenic Trioxide As a Front-Line Therapy for Newly Diagnosed Acute Promyelocytic Leukemia
Authors: Chen Weihong , Du Xin , Zhuo Jiacai
Published: October 2019

PURPOSE:

Arsenic trioxide (ATO) is a very effective drug for acute promyelocytic leukemia (APL). However, little has been reported concerning its use as front-line therapy for complete remission of newly diagnosed APL with t(15;17) chromosomal abnormality.

METHODS:

The adult patients newly diagnosed with APL with t(15;17) chromosomal abnormality (which would invariably lead to a positive PML/RAR alpha fusion gene) were received 4-5 weeks of ATO administered intravenous drip at a daily dose of 10mg(concentration 2%)/day as induced chemotherapy. When a complete remission was achieved by the ATO induction, a three weeks interval would be observed, after which 5 + 3 days of maintenance (with cytarabine and anthracycline, respectively) would be carried out. A further interval of 2 weeks would then take place, after which all-trans retinoic (ATRA) would be administered oral for another 2 weeks. A final interval of 2 weeks after the administration of ATRA would take place before a recurrence of the chemotherapy regimen, which would restart again with ATO induction. After PML/RAR alpha fusion gene Q-PCR tested negative, the regimen would continue recurring, ensuring negativity of the gene for 2 years. After 2 years the regimen would end, and PML/RAR alpha fusion gene of the patients were to be observed/monitored once every 3-6 months for 10 years. Central nervous system leukemia (CNSL), which might be caused by APL, was to be prevented by lumbar punctures chemotherapy once every 6-8 weeks after complete remission of the patients. Six times were taken.

RESULTS:

Out of 496 for newly diagnosed APL from 2005 to 2015, we identified 113 patients as newly diagnosed APL. All patients achieved complete response after treatment with ATO induced chemotherapy. Sixty-two out of 65 (95.38%) patients with APL were cured with ATO induction and subsequent 5 + 3 maintenance (cytarabine and anthracycline) therapy from 2005 to 2010. The other three patients were relapsed or had refractory disease and then died. Forty-six out of 48 patients (95.83%) achieved complete cytogenetic remission from 2011 to 2015. The other two patients were relapsed or had refractory disease and then died. All patients had no serious adverse events. Five patients had dyspnea, fever, weight gain, peripheral edema and were successfully treated with dexamethason and furosemide.

CONCLUSIONS:

Arsenic trioxide is a very effective drug as the front-line therapy for newly diagnosed acute promyelocytic leukemia.

Disclosures

No relevant conflicts of interest to declare.
A Novel 3D Extracellular Matrix Model Enriching Human Acute Myeloid Leukemia Stem Cells
Authors: Li Dandan , Lin Tara L. , Hopkins Richard , Aljitawi Omar S.
Published: October 2019

Background and objective: Acute myeloid leukemia (AML) develops from leukemia stem cells (LSCs), a small subset of leukemia cells possessing both self-renewal and multilineage differentiation potential similar to normal hematopoietic stem cells. The stem cell niche of the bone marrow microenvironment protects LSCs from chemotherapy, resulting in subsequent leukemia relapse. The study of AML LSCs in vitro is limited because of the lack of an ideal culture system mimicking the protective bone marrow microenvironment. The bone marrow stem cell niche is mainly composed of stromal cells, soluble cytokines and growth factors, as well as extracellular matrix (ECM). We therefore developed a 3-dimensional ECM model using decellularized Wharton's jelly from human umbilical cords to better characterize AML LSCs in vitro. Previously we have shown that leukemia cells grown in DWJM changed morphology to become spindle shaped and maintained viability but had decreased proliferation as measured by Alamar blue assay. Herein, we further characterize leukemia cells cultured in DWJM.

Methods: Wharton's jelly decellularization process included multiple osmotic shock cycles using hypertonic and hypotonic solutions, a non-ionic detergent Triton-x, an anionic detergent sodium lauroyl succinate, and an enzyme digestion with recombinant endonuclease Benzonase™. We examined three human leukemia cell lines: HL60, Kasumi I and MV411. We characterized leukemia cell proliferation by CellTrace proliferation assay and phenotype by flow cytometry for stem cell markers. Serial colony forming unit (CFU) assays were used to test the self-renewal of leukemia cells.

Results: CellTrace proliferation assay showed that, compared to cells in suspension, cells cultured in DWJM divided less frequently. To assess for LSCs properties, we measured the ALDH+ population by Aldefluor assay and found that the ALDH+ cells from Kasumi I and HL60 increased significantly in DWJM compared to suspension (p<0.05). Lastly, serial CFU showed significantly increased colony forming units in both primary and secondary plating in MV411 and HL60 cells cultured in DWJM versus suspension (P<0.05). CFU also increased in Kasumi-I cells cultured in DWJM versus suspension, though the increase was not statistically significant (P=0.08). Taken together, our findings suggest that leukemia cells cultured in DWJM demonstrated an increased self-renewal ability due to the enrichment of LSCs rather than progenitors.

Conclusion: Decellularized Wharton's jelly matrix may serve as a practical in vitro ECM model to enrich for LSCs and study the ECM-LSC interactions.

Disclosures

No relevant conflicts of interest to declare.
Analysis of the Expression of PHTF1 and Related Genes in Acute Lymphoblastic Leukemia
Authors: Huang Xin , Geng Suxia , Weng Jianyu , Lu Zesheng , Zeng Linji , Li Minming , Deng Chengxin , Wu Xiuli , Li Yangqiu , Du Xin
Published: October 2019

Background: In the human T-cell acute lymphoblastic leukemia (T-ALL) cell line Molt-4, siRNA-mediated suppression of BCL11B expression was shown to inhibit proliferation and induce apoptosis, which may be related to PHTF1 gene expression, and the FEM1B and Apaf-1 genes may be downstream of PHTF1. In this study, we analyzed the expression level of PHTF1 and related genes in patients with ALL to clarify the role of the PHTF1-FEM1b-Apaf-1 pathway in hematologic malignancies.

Methods: Fifteen newly diagnosed and untreated patients with AML, fourteen newly diagnosed and untreated patients with CML in chronic phase, twenty-two newly diagnosed and untreated patients with ALL, and six newly diagnosed and untreated patients with CLL were recruited. Peripheral blood mononuclear cells (PBMCs) from ten healthy individuals (HIs) served as controls. PBMCs were separated using the Ficoll-Hypaque gradient centrifugation method. All procedures were conducted in accordance with the guidelines of the Medical Ethics committees of the Health Bureau of Guangdong Province, China.Real-time PCR was used to determine the gene expression level of PHTF1 in hematologic malignancies. The PHTF1, BCL11B, FEM1B and Apaf-1 gene expression levels and correlations were analyzed in patients with primary ALL and healthy individuals (HIs).

Results: PHTF1 overexpression was found in recently diagnosed AML (p <0.001), CML-CP (p<0.001), and ALL (p= 0.016) patients in comparison with HIs. The PHTF1 expression level in CLL patients was not significantly different compared with HIs (p= 0.165). FEM1b and Apaf-1 overexpression was found in recently diagnosed ALL (p<0.005) patients compared with HIs. Positively correlated expression was found for the PHTF1, FEM1b and Apaf-1 genes in patients with ALL (p<0.005) and HIs (p<0.005), and positively correlated expression was found for the PHTF1 and BCL11B genes in HIs (p<0.005).

Conclusions: PHTF1 acts as a tumor suppressor gene, and its overexpression might be related to cell proliferation, inhibition and apoptosis. PHTF1 and BCL11B gene disorders may contribute to T-ALL pathogenesis. PHTF1 might be a therapeutic target for triggering the PHTF1-FEM1b-Apaf-1 apoptosis pathway in primary acute lymphoblastic leukemia.

Acknowledgment

The project was sponsored by grants from National Natural Science Foundation of China (No. 81100384, No. 81270648, No.91129720, and No. 30771980)

Disclosures

No relevant conflicts of interest to declare.
B Cell Lymphoma Unclassifiable, with Features Intermediate Between Diffuse Large B Cell Lymphoma and Burkitt Lymphoma and Diffuse Large B Cell Lymphoma NOS with Doble/Triple Translocations: Immunophenotypic Analysis
Authors: González de Villambrosia Sonia , Colorado Mercedes , Insunza Andres , Batlle Ana , López-Pereira Brenda , Martin Guillermo , Ibarrondo Paloma , Montes-Moreno Santiago , Conde Eulogio
Published: October 2019

Background: Diffuse large B-cell lymphoma (DLBCL) is a clinically and molecularly heterogeneous disease. We can identify two subgroups with aggressive clinical course and higher risk of treatment failure after standard therapy: B cell lymphoma unclassifiable (BCLU) with features intermediate between DLBCL and Burkitt lymphoma (BL) and B-cell lymphomas with double/triple translocation (DHL/THL). Previous reports suggest that these types of lymphomas may show a common immunophenotype, providing another tool in the challenge of their diagnosis.

Objetives: To analyze the immnunophenotype (IF) of BCLU and DH/TH lymphomas by multiparametric flow cytometry and compare it with the IF of a series of cases with DLBCL and BL.

Methods: we analyzed the inmunophenotype (four-color flow cytometry on a FACSCalibur flow cytometer) and cytogenetic studies (FISH to detect MYC, BCL2 and/or BCL6 rearrangement) of cases diagnosed of BCLU and DH/TH lymphomas. Control cases of DLBCL and BL were consecutively collected from our database. Fisher`s Exact test was used to compare proportions between two groups. P-values <0.05 were considered statistically significant.

Results: We analyzed 23 controls (14 DLBCL and 9 BL) and 17 cases: 9 DHL (8 BCL2/MYC+ and 1 BCL6/MYC+), 3 THL (BCL2/BCL6/MYC+) and 5 BCLU (1 IGH-MYC+, 3 MYC+ and 1 unknown). Six of the 17 cases (35.3%) had decreased expression of CD19 while this was exceptional in DLBCL (1/10 P=0.073) and BL (0/9 P=0.054). All of the cases were positive for CD20 but with different intensities: only 5.9% expressed high CD20 compared to 42.9% of DLBCL (p=0.021) and 55.6% of BL (P=0.010). Most of the cases (12/17) had intermediate expression of CD20 and only 4/17 had weak expression. CD10 expression was typical in BL (100%) and frequent in the cases (82.4%), while it was only present in 20% of DLBCL (P<0.0001). CD38 expression was high in 100% of BL, 6.3% of the cases and none of DLBCL. It was intermediate in 64.7% of the cases and in 35.7% of DLBCL (P=0.015). BCL2 overexpression was detected in 57.1% of the cases; neither DLBCL nor BL (P= 0.009) had BCL2 overexpression.

Conclusions: We identify a common immunophenotype in DH/TH lymphomas and BCLU: decreased expression of CD19 and CD20, CD10 expression, overexpression of BCL2 and intermediate expression of CD38. This immuphenotype may be useful for identifying cases for confirmatory cytogenetic studies. Larger studies are needed to validate these results.

Disclosures

No relevant conflicts of interest to declare.
The Neutrophil-Lymphocyte Ratio Is a Prognostic Marker in Patients with EBV-Positive Diffuse Large B-Cell Lymphoma
Authors: Beltran Brady E , Malaga Jose M , Chavez Julio C , Sotomayor Eduardo M. , Castillo Jorge J
Published: October 2019

Introduction: Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) is a rare hematologic malignancy with a poor prognosis when treated with current therapies. Clinical factors have been developed to prognosticate survival in EBV-positive DLBCL patients; however, more refined, easy to use and reliable prognostic tools are needed. The neutrophil to lymphocyte ratio (NLR) has been reported prognostic in patients with DLBCL (Troppan et al. BJC 2014). We have investigated the prognostic value of the NLR in the overall survival (OS) of patients with untreated EBV-positive DLBCL.

Methods: We included patients with a pathological diagnosis of EBV-positive DLBCL who were diagnosed and treated at our institution between 2001-2014. We excluded cases with primary cutaneous CNS involvement, and patients with >50% incomplete data. IRB approval was obtained prior to research. Pathological samples were reviewed by hematopathologists to confirm the diagnosis. Pertinent clinicopathological data such as age, sex, performance status, LDH levels, stage, extranodal sites of disease, absolute neutrophil and lymphocyte counts were collected through chart review, and are presented using descriptive statistics. The NLR was calculated by dividing the absolute neutrophil by the lymphocyte count, and dichotomized in NLR>=5 and NLR<5. Survival curves were estimated using the Kaplan-Meier method and compared using the log-rank test. Univariate Cox models were fitted to evaluate hazard ratios (HR) for OS.

Results: A total of 46 patients were included in our analysis. The median age was 73 years (range 25-95 years) with male predominance (70%). Poor performance status (ECOG >1) was seen in 25 (58%), elevated LDH levels in 19 (46%), 1+ extranodal site in 24 (57%), and advanced stage (stage 3 and 4) in 23 (53%) of patients. Based on the NLR, 13 patients (39%) had NLR>=5. Patients with NLR >=5 were more likely to present with poor performance (ECOG >1; 85% vs. 15%; p=0.04), elevated LDH levels (69% vs. 31%; p=0.04), advanced stage (III and IV, 69% vs. 31%, p=0.05), and IPI score 3-5 (77% vs.23%; p=0.02). There were no differences in age, sex and number of extranodal sites. NLR>=5 was associated with a worse OS (HR 2.67, 95% CI 1.01-7.01; p=0.047).

Conclusion: The NLR appears as a novel and easy to use prognostic factor for OS in patients with untreated EBV-positive DLBCL. Our findings support the need for validation of the NLR in larger retrospective or prospective studies in patients with EBV-positive DLBCL.

Figure 1. Figure 1.

Disclosures

No relevant conflicts of interest to declare.
MYD88 L265P Mutation Is a Possible Unfavorable Prognostic Factor in Patients with Diffuse B-Cell Lymphoma
Authors: Sidorova Anna A. , Zvonkov Eugene E. , Sudarikov Andrey B. , Severina Nataliya A. , Kovrigina Alla M. , Troitskaya Vera V. , Savchenko Valeri G.
Published: October 2019

INTRODUCTION

Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma. Activated B-cell like (ABC) molecular subtype DLBCL is characterized by more aggressive behavior and poor clinical outcomes with standard R-CHOP chemotherapy. Approximately 30% of all patients (pts) with ABC DLBCL have recurrent mutation in the MYD88 gene (a change from leucine to proline at position 256 - L256P). We report the impact of the MYD88 mutation status on the clinical course and outcome of pts with ABC DLBCL.

METHODS

In present study MYD88 mutation status was investigated in untreated pts with ABC DLBCL.

The diagnosis of ABC DLBCL was established according to the WHO 2008 classification. DNA from 41 cryopreserved and 12 formalin-fixed paraffin-embedded tumor samples were tested in our study. Sanger sequencing and real-time allele-specific PCR was used to assess MYD88 L265P mutation status.

RESULTS

We report data for 53 pts (34 male, 19 female) with a median age of 53 (18-74) years. MYD88 L265P mutation was detected in 26,4% (14/53) of pts. The international prognostic index (IPI) score was 4-5 in 7/14 (50%) of pts with MYD88 mutated DLBCL and 12/39 (30,8%) pts with MYD88 wild type DLBCL, whereas nearly half of all pts presented with Ann Arbor stage IV disease. The majority of pts 13/14 (93%) with MYD88-positive DLBCL had elevated lactate dehydrogenase levels versus 26/39 (66%) pts with MYD88 unmutated DLBCL. Extranodal was more common in pts with MYD88 mutation than in pts with MYD88 unmutated DLBCL (78,5% vs 54%). All pts received high-dose chemotherapy and were followed for 50,5 (11-95) month. Pts with MYD88 mutation had similar complete response rate comparing to pts without MYD88 mutation (78,6% vs 84,6%). The disease relapsed in 45,4% of pts with MYD88 mutation and in 24,2% of pts without MYD88 mutation. Mortality was in 45,4% of pts with MYD88 mutation and in 24,2% of pts without MYD88 mutation. Overall survival (OS) was better in pts with MYD88 unmutated DLBCL than in pts with MYD88 positive DLBCL (5-year OS, 73% vs 31%).

CONCLUSION

IPI high risk and extranodal involvement is common in ABC DLBCL pts with MYD88 L265P mutation. MYD88 L265P mutation can be a predisposing factor for poor OS probability in pts with ABC DLBCL.

Disclosures

No relevant conflicts of interest to declare.
Consolidative Treatment after Salvage Chemotherapy Improved Prognosis in Patients with Relapsed Extranodal Natural Killer/T-Cell Lymphoma
Authors: Bi Xi-Wen , Zhang Wen-Wen , Huang Jia-Jia , Xia Zhongjun , Li Zhi-Ming , Jiang Wenqi
Published: October 2019

The optimal treatment strategy and prognosis for patients with relapsed natural killer/T-cell lymphoma (NKTCL) remain largely unknown. The treatment modalities and prognosis of fifty-six patients with relapsed NKTCL were retrospectively reviewed. Twenty-three (41.1%) patients had locoregional relapse alone, while 33 (58.9%) had distant with or without locoregional relapse. Chemotherapy was the initial salvage treatment, followed by radiotherapy (RT) or autologous hematopoietic stem cell transplantation (AHSCT) as consolidative therapy, depending on the status of remission and the pattern of relapse. The 5-year overall survival (OS) after relapse was 41.4% for the entire cohort. Complete remission (CR) after salvage treatment was associated with a substantially better survival (5-year OS after relapse: 74.7 vs. 7.8%, P < 0.001). For patients with locoregional relapse alone, consolidative RT after response to salvage chemotherapy significantly improved prognosis compared with follow-up (5-year OS: 83.3 vs. 41.7%, P = 0.047). For patients with distant relapse, the addition of consolidative AHSCT after response to chemotherapy significantly prolonged survival than follow-up (2-year OS: 100.0 vs. 20.0%, P = 0.004). Patients without consolidative treatment after response to salvage chemotherapy had a comparable survival to those who experienced stable or progressive disease after chemotherapy, regardless of the relapse pattern. Asparaginase (ASP)-containing salvage chemotherapy failed to convey a survival advantage over ASP-absent chemotherapy (5-year OS: 44.2 vs. 39.3%, P = 0.369). Patients who received ASP-containing chemotherapy in the first-line treatment had a poorer response to salvage chemotherapy and worse prognosis after relapse, compared with those receiving ASP-absent first-line chemotherapy. Consolidative RT or AHSCT improved prognosis in patients with relapsed NKTCL who responded to initial salvage chemotherapy. The role of ASP in salvage chemotherapy after relapse required further exploration in prospective studies.

Disclosures

No relevant conflicts of interest to declare.
The Frequency of Occurrence of Minimal Residual Disease into Different Prognostic Groups of Patients with Chronic Lymphocytic Leukemia
Authors: Kuvshinov Aleksei , Voloshin Sergei , Martynkevich Irina , Martynenko Ludmila , Garifullin Andrei , Kleina Elizaveta , Abdulkadyrov Kudrat
Published: October 2019

Background. It is known, that genetic factors and the absence of minimal residual disease (MRD) are strongly affecting prognosis of chronic lymphocytic leukemia (CLL).

Aim. To determine the influence of genetic abnormalities (GA) on achieving MRD-negative remissions in patients with CLL.

Methods. Twenty-four adult pts (median age 57 years, range 35-67; male 14, female 10) with newly diagnosed CLL were included. The CLL was diagnosed according to the standard basic examination (complete blood count with differential, multicolor flow cytometry (MFC) of blood and bone marrow (BM), lymph node and BM immunohistochemistry (IHC), computered tomography). Cytogenetic studies were performed on blood samples using standard GTG-method. Interphase FISH analyses were performed according to the manufacturer's protocol using DNA probes: LSI 13(RB1)13q14, LSI ATM (11q22), CEP12, LSI TP53 (17p13.1) (Abbott). Immunophenotype (IFT) of CLL cells assessed with combinations: CD3/CD19, CD19/CD5, CD19/CD11c, CD19/CD20, CD19/CD22, CD19/CD23, CD19/CD25, CD19/CD38, CD19/CD43, CD19/CD81, CD19/HLA-DR, and CD19/CD5/CD23. We have used NCI revised guidelines (Hallek M, et al., 2008) for treatment initiation and assessment of response after completion of primary therapy with rituximab-based regimens (FCR or RB). All patients treated subsequently with rituximab maintenance. MRD was detected by MFC.

Results. The frequency of GA in CLL was 50.0% (12/24): 15.0% (3/20) - by conventional karyotyping, 47.8% (11/23) - by FISH analyses and 9.5% (2/21) - using both methods. Stratification of patients into prognostic groups based on identified GA. Favorable prognosis (Group 1) - patients with del(13q) (n = 5); neutral prognosis (Group 2) - normal karyotype (n = 12) or trisomy of chromosome 12 (n = 3); unfavorable prognosis (Group 3) - del(11q) (n = 3) or the complex karyotype (n = 1).

Statistically significant differences in the frequency of achieving MRD-negative remissions between FCR (5/11) vs. RB (5/13) were not detected (p<0.05).

Complete remissions (CR) were reached in 37.5% (9/24) pts, partial remissions (PR) - 62.5% (15/24). The MRD-negative remissions were reached in 10 patients: in Group 1 - 2/5 (40%; CR - 1), in Group 2 - 5/15 (33.3%, CR - 6), in Group 3 - 75.0% (3/4; CR - 2).

Statistically significant differences in PFS were detected between MRD-negative vs. MRD-positive groups (p=0.03). Median PFS in MRD-negative has not been reached. Median PFS MRD-positive was 33.1 month.

Conclusions. Further researches aimed at examining the relationship between the presence or absence of MRD and genetic prognostic groups, will help to understand the most important factors affecting the overall and progression-free survival.

Disclosures

No relevant conflicts of interest to declare.
Neutrophil-Secreted Proteinase 3 Mediates Metastasis of Prostate Cancer Cells Expressing RAGE to the Bone Marrow
Authors: Kolonin Mikhail , Sergeeva Anna , Staquicini Daniela , Molldrem Jeffrey J. , Pasqualini Renata , Arap Wadih
Published: October 2019

Human prostate cancer non-randomly metastasizes to the bone marrow, but the biological basis for such site-specific tropism remains largely unresolved. Differential expression of molecules in the bone marrow microenvironment "niche" has recently been proposed to play a role. In previous work, combinatorial selection of random peptide libraries in end-of-life cancer patients has revealed an unexpected interaction between the receptor for advanced glycation end products (RAGE), a molecule expressed on malignant cell surfaces in advanced prostate cancer, and proteinase 3 (PR3), a serine protease abundantly present on neutrophils and promyelocytes within the bone marrow microenvironment. Because RAGE is selectively overexpressed in prostate cancer bone metastases, we hypothesize here that its specific binding to PR3 might mediate homing of prostate cancer cells to the bone marrow. We demonstrate that PR3 non-proteolytically binds to RAGE on prostate cancer cell surfaces and thereby promotes tumor cell activation and motility. We also show that the downstream signal transduction cascade triggered by RAGE/PR3 binding involves p44/42 (Erk1/2) and JNK1 phosphorylation. Finally, we use a mouse model of experimental metastasis to demonstrate that RAGE protein expression on human prostate cancer cells promotes their homing to bone marrow within a short time frame. These results validate a functional protein interaction between RAGE and PR3 and uncover a mechanism through which neutrophils mediate prostate cancer cell metastasis to the skeleton.

Disclosures

Sergeeva: Astellas: Patents & Royalties. Molldrem:Astellas Pharma: Patents & Royalties.
Thymidine Phosphorylase Exerts Complex Effects on Bone Resorption and Formation in Myeloma
Authors: Liu Huan , Liu Zhiqiang , Du Juan , He Jin , Lin Pei , Behrang Amini , Starbuck Michael W , Novane Nora M , Shah Jatin J. , Davis Richard Eric , Hou Jian , Gagel Robert , Yang Jing
Published: October 2019

Thymidine phosphorylase (TP), an enzyme that can reversibly catalyze the conversion of thymidine to thymine and 2-deoxy-D-ribose (2DDR), has been shown to participate in tumor angiogenesis and proliferation. Yet little is known regarding its function in bone. The goal of this study is to elucidate the role and mechanism of myeloma-expressed TP in the activation of osteoclast-mediated bone resorption and the suppression of osteoblast-mediated bone formation. We hypothesized that myeloma-expressed TP plays an important role in the pathogenesis of myeloma bone disease. We observed that TP is highly expressed in myeloma cells but not in normal plasma cells. To examine the role of myeloma-expressed TP in lytic bone lesions, we categorized all tested patient-derived myeloma cells and human myeloma cell lines into two groups: TP-high and TP-low expressing cells. These myeloma cells, as well as human myeloma cells with overexpressed or knocked downed levels of TP, were injected into the implanted human bone chips of SCID-hu mice or the femurs of SCID mice. Analysis of radiography and histomorphometry were used for assessing lytic lesions. Our results showed that injection of TP-high expressing myeloma cells into mice caused more lytic lesions than injection of TP-low cells. To examine its role in osteoclast and osteoblast differentiation, the progenitors were co-cultured with the myeloma cells, and analyzed with staining of TRAP and Alizarin red S. We observed that co-culture with TP-high expressing myeloma cells induced more osteoclast differentiation and less osteoblast formation than those co-cultured with TP-low cells. Mechanistic studies further showed that TP-high expressing myeloma cells secreted more 2DDR than TP-low cells. The secreted 2DDR bound to the integrin aVb3 in osteoclast progenitors, activated the PI3K/Akt signaling, and enhanced DNMT3A expression and methylation of IRF8, leading to increased NFATc1 expression and osteoclast differentiation. The secreted 2DDR could also bind to the integrins aVb3 and a5b1 in osteoblast progenitors, activated the PI3K/Akt signaling, and enhanced DNMT3A expression and methylation of RUNX2 and osterix, leading to decreased osteoblast differentiation. We further examined the patient bone marrow samples, and demonstrated a positive correlation between TP expression in myeloma cells and osteolytic bone lesions in myeloma patients. Thus, our study not only elucidates a novel mechanism of myeloma-induced increased osteoclast-mediated bone resorption and suppressed osteoblast-mediated bone formation, but also implicates a potential therapeutic approach for myeloma bone disease.

Disclosures

No relevant conflicts of interest to declare.
Comparison of Clinical Diagnosis for Hereditary Spherocytosis with Molecular Diagnosis By Multi-Gene Target Sequencing in Korea
Authors: Choi Hyoung Soo , Choi Qute , Kim Jung Ah , Im Kyong Ok , Park Si Nae , Park Yoomi , Kim Ju Han , Shin Hee Young , Kim Seon Young , Kang Hyoung Jin , Kook Hoon , Kim Soo-Jeong , Kim Inho , Kim Ji Yoon , Kim Hawk , Park Kyung Duk , Park Kyung Bae , Park Meerim , Park Sang Kyu , Park Eun Sil , Park Jeong-A , Park Ji Kyoung , Baek Hee Jo , Seo Jeong Ho , Shim Ye Jee , Ahn Hyo Seop , Yoo Keon Hee , Yoon Hoi Soo , Lee Kun Soo , Lee Kwang Chul , Lee Jae Min , Lee Mee Jeong , Lee Sun Ah , Lee Jun Ah , Lee Jae Hee , Lee Ji Won , Won Young-Woong , Lim Young Tak , Jung Hyun Joo , Cheuh Hee Won , Choi Eun Jin , Jung Hye Lim , Lee Dong Soon , the Korean Society of Hematology The Hereditary Hemolytic Anemia Working Party of
Published: October 2019

Background: Hereditary spherocytosis (HS) is the most common cause of hereditary hemolytic anemia. Current tests used to diagnose HS focus on the detection of hemolysis or indirectly assess protein defects. Direct methods to detect protein defects are complicated and difficult to implement. Recent next-generation sequencing (NGS) methods enable large-scale gene mutation analyses to be used for such diagnoses. In this study, we investigated the patterns of genetic variation associated with HS among the patients diagnosed with HS clinically. Specifically, we analyzed mutations in red blood cell membrane protein-encoding genes (17 genes) in context with 5 genes for the differential diagnosis (thalassemia, congenital dyserythropoietic anemia, paroxysmal nocturnal hemoglobinuria) in Korean HS.

Methods: In total, 60 patients diagnosed with HS were enrolled in this study. Targeted sequencing of 43 genes (17 membrane protein-encoding genes, 20 enzyme-encoding genes, and 6 additional candidate genes) was performed using the Illumina HiSeq platform and variants were called according to a data-processing pipeline.

Results: Of the 60 patients, 50 (83%) had one or more significant variants in a membrane protein encoding genes. A total of 54 significant variants (8 previously reported and 46 novel) were detected in 6 membrane protein-encoding genes; SPTB, ANK1, SPTA1, SLC4A1, EPB41, and EPB42. The most variants (28/60 patients) were detected in SPTB. Interestingly, concurrent mutations of genes encoding enzymes (ALDOB, GAPDH, and GSR) were detected along with mutations of membrane encoding genes. One patient diagnosed with HS harbored mutation of G6PD without mutation of HS related genes. Additionally, UGT1A1 mutations were present in 5 patients. Positive rate of osmotic fragility test was 86% among patients with HS related gene mutations.

Conclusion: These results clarify the molecular genetic analysis is required for the accurate diagnosis of HS. About 17% of patients who were clinically diagnosed as HS revealed discrepancy with molecular diagnosis.

Figure Figure.

Disclosures

No relevant conflicts of interest to declare.
Outcome of Frontline Treatment with Generic Imatinib in Adult Patients with Chronic Myeloid Leukemia in Algerian Population: A First Multicenter Study
Authors: Entasoltan Badra , Bekadja Mohamed Amine , Bouhass Rachid Amar , Taibi Karima , Touhami Hadj , Mehalhal Nemra , Benlazar Mohamed , Zouaoui Zahia , Benzineb Brahim , Mesli Naima , Talbi Mustapha , Yachekour Toufik , Bachiri Aissa , Nachi Mourad
Published: October 2019

Introduction:

In a developing country like Algeria, such expensive therapy is not available. Alternative approaches are needed to help these adult. In Algeria 'imatib' (CIPLA-India) was introduced in 2006; but no study has been published yet in the North Africa region regarding response and outcome of this copy in CML patients. The goal of this multicenter study is to characterize newly adult CML in the western region of Algeria and to assess the effectiveness and safety of imatib (IM, copy) as frontline therapy for patients with CML.

Patients and Methods:

The study was carried out in 7 hematology centers in the western Algeria. Patients, who were diagnosed to be suffering from CML between 1st January, 2007 and 31st December, 2014 were selected for data analysis. All patients received a copy preparation, consisting of the alpha crystal form of imatinib, (IM, copy) at a oral dose of 400 mg daily and monitored for tolerance and side effects while on therapy.

Results:

Between January 2007 and December 2014, 355 patients with CML were treated with imatib (copy). The median follow- up of the study was 46 months (range: 13-107 months). Complete hematological response (CHR) was seen in 83% of patients within 3 months. According to the Sokal score, 72% patients with low, 78% with intermediate and 69% with high risk disease achieved a CHR in 3 months (p=0.26) and according to the EUTOS score, 81% of patients with low and 70% with high risk disease achieved a CHR in 3 months (p=0.08). The major molecular response (MMR) at six months (M6), M9, M12, M18 and M24 was 21%, 38%, 35%, 51% and 67% respectively and 34% of patients achieved a complete molecular response (CMR). The projected 5-year overall survival (OS) rate was 83%. Side effects of imatib (copy) in this study were similar to those reported previously for the entire imatinib mesylate treatment study and only 8% of patients were intolerant to imatib (copy) and treated with a second generation of BCR-ABL inhibitor.

Conclusion:

In conclusion, imatib (copy) is effective and safe in treating patients with CML in chronic phase and proves to have a durable outcome. To our knowledge this is the first study reporting the response to imatib (copy) in a Algerian population.

Disclosures

No relevant conflicts of interest to declare.
Long-Term Survival and Quality of Life Analysis after Autologous Stem Cell Transplantation for Lymphoma
Authors: Faict Sylvia , De Beule Nathan , De Becker Ann , Fostier Karel , Trullemans Fabienne , Schots Henri (Rik)
Published: October 2019

Background

Autologous stem cell transplantation (ASCT) is a frequent treatment option for various types of lymphoma. Few studies have addressed the occurrence of long-term morbidity and the quality of life (QoL) after ASCT. We analysed the overall survival (OS), the QoL and the impact of comorbidities before and after transplant in a consecutive cohort of lymphoma patients.

Methods

Patients transplanted in our center between 2003 and 2013 and with a minimum follow-up of 1 year were included. Survival was analysed by Kaplan-Meier methodology and the impact of prognostic factors was examined by standard multivariate analysis. Patients were inquired to complete the Self-reported Comorbidity Questionnaire (SCQ) as well as the EORTC QLQ-C30. Results of questionnaires were compared to a healthy reference population.

Results

A total of 85 lymphoma patients were identified with a median follow-up period of 76 months. The estimated OS probability was 62,7% (S.E. 5,5%) at 5 years and 60,8% (S.E. 5,6%) at 10,9 years. Indicators of a poor prognosis at time of transplantation were: age ≥ 60 years, high-intermediate to high-risk IPI for NHL and HCT-comorbidity index ≥ 3. Of long-term (> 1 year) survivors 40 completed the EORTC QLQ-C30. They experienced lower cognitive and social functioning and reported more fatigue, dyspnea and financial difficulties, when compared to the reference population. A small proportion of patients reported significant complaints related to pain (22,5%) and fatigue (10%). Very long-term survivors (over 5 years post ASCT) had a better physical and role functioning, with less fatigue, dyspnea, insomnia and loss of appetite as compared to patients who were transplanted more recently. Patients with more self-reported comorbidities post-ASCT did significantly worse in terms of QoL after transplantation. They experienced worse physical, role, cognitive and social functioning, and had more complaints about fatigue, pain, dyspnea, diarrhea and insomnia.

Conclusion

The presence of comorbidities pre-ASCT, as determined by HCT-CI >3, was associated with a worse OS. Surprisingly, the overall long-term impact of ASCT on the QOL was limited with adverse effects only related to cognitive and social functions. These negative consequences also decreased over time. Finally, the occurrence of comorbidities after transplantation was associated with worse QoL.

Disclosures

No relevant conflicts of interest to declare.
Population Level Survival for Patients with Rare Hematologic Malignancies in the United States in the Early 21st Century
Authors: Pulte Dianne , Weberpals Janick , Jansen Lina , Katalinic Alexander , Nennecke Alice , Holleczek Bernd , Ressing Meike , Luttmann Sabine , Brenner Hermann
Published: October 2019

Introduction: Population level survival has increased for most of the more common hematologic malignancies in the early 21st century. However, less information is available on population level changes in survival for patients with rare hematologic malignancies. Here, we examine survival for rare hematologic malignancies in Germany and the United States (US).

Methods: Cases of rare hematologic malignancies were extracted from the Surveillance, Epidemiology, and End Results (SEER13) database in the US, with an underlying population of 44.1 million people, and 12 regional cancer databases in Germany, with an underlying population of 28.3 million. For the purpose of this study, rare hematologic malignancies were defined as those having an incidence of less than 1 per 10,000 population in both the relevant databases. Modeled period analysis was used to examine changes in 5-year survival between 2003-07 and 2008-12 and to derive p-values for the comparison between the two periods.

Results: Ten malignancies that met the inclusion criteria and had adequate case numbers to allow a meaningful analysis were identified (see table.) A total of 13,895 cases were identified in Germany and 19,894 in the US with case numbers for individual morphologies ranging from 302 for acute erythroblastic leukemia in Germany to 4,514 for mantle cell lymphoma in the US. Overall 5-year relative survival for patients with all morphologies was estimated as 60.4% in Germany and 57.2% in the US in 2008-12. Survival for patients varied widely depending on the individual tumor type, from less than 30% for acute monoblastic leukemia and acute erythroblastic leukemia to around 90% for hairy cell leukemia and mycosis fungoides without Sezary. A statistically significant increase in survival was observed for mantle cell lymphoma, Burkitt's lymphoma, and hairy cell leukemia in Germany and for mantle cell lymphoma, anaplastic lymphoma kinase (ALK) positive anaplastic lymphoma, and acute erythroblastic leukemia in the US.

Conclusions: Five year survival varied widely for rare hematologic malignancies in Germany and the US. Significant increases in survival were observed in only a minority of rare hematologic malignancies, in contrast to the consistent increases in survival seen in almost all of the more common hematologic malignancies. Survival was lower in the US for most malignancies. Research specifically focusing on rare hematologic cancer types is needed to increase survival for these conditions.

Table Five year relative survival for rare hematologic malignancies, 2003-07 to 2008-12. Table. Five year relative survival for rare hematologic malignancies, 2003-07 to 2008-12.

Disclosures

Pulte: ApoPharma: Research Funding; Selexys Pharmaceuticals: Research Funding; EBSCO: Other: Review of content for Dynamed medical reference product.
RAB14 Regulates Human Erythropoiesis and Megakaryopoiesis
Authors: Kim Minjung , Kingsbury Tami J. , Civin Curt I.
Published: October 2019

We recently reported that RAB GTPase 14 (RAB14) knockdown (KD) increased the frequency and total numbers of erythroid cells generated in vitro in response to erythropoietin (EPO) from either the TF1 human leukemia erythropoietic model cell line or from primary human CD34+ hematopoietic stem-progenitor cells (HSPCs). RAB14 overexpression (OE) had the opposite effect. Thus, RAB14 functions as an endogenous inhibitor of human erythropoiesis (Kim et al., Br. J. Haematol., 2015). In contrast to the greater cell numbers generated in the presence of EPO, RAB14 KD TF1 cells grown in standard culture media containing granulocyte-macrophage colony-stimulating factor (GM-CSF; as the only cytokine) generated fewer total cells, compared to empty vector-transduced control TF1 cells. Furthermore, RAB14 KD TF1 cells cultured in GM-CSF media generated greater numbers of erythroid (CD34-/CD71+/CD235a+) cells, as compared to control TF1 cells, suggesting that RAB14 KD stimulated erythropoiesis even in the absence of EPO. Cells generated from RAB14 KD TF1 cells had higher GATA1 and lower GATA2 transcription factor expression, as compared to controls, demonstrating the cells had undergone the "GATA1/2 switch," a hallmark of erythropoiesis. Consistent with higher GATA1 levels, RAB14 KD TF1 cells generated cells with higher levels of b- and g-hemoglobins. Similarly, RAB14 KD in primary human CD34+ HSPCs generated greater numbers of erythroid cells, with or without exogenous EPO. RAB14 KD CD34+ HSPCs cultured in GM-CSF media generated fewer monocytic/granulocytic (CD13+/CD33+) cells, as compared to control CD34+ HSPCs. Interestingly, RAB14 OE CD34+ HSPCs cultured in thrombopoietin (TPO)-containing media generated higher numbers of megakaryocytic (CD34-/CD41a+/CD42b+) cells, as compared to control CD34+ HSPCs. In summary, (1) RAB14 KD in TF1 cells or primary human CD34+ HSPCs increased erythropoiesis in the presence or absence of EPO, but reduced myeloid cell differentiation, probably via the GATA1/2 switch; and (2) RAB14 OE in CD34+ HSPCs increased megakaryopoiesis in the presence of TPO. Thus, RAB14 normally serves as an endogenous hematopoietic decision-maker, physiologically inhibiting erythropoiesis and stimulating megakaryopoiesis (and possibly, to a lesser extent, mono-granulopoiesis).

Disclosures

No relevant conflicts of interest to declare.
Suppression of Anti-Tumor Immunity in Chronic Lymphocytic Leukemia Via Interleukin-10 Production
Authors: Alhakeem Sara S , McKenna Mary K , Nooti Sunil K , Oben Karine Z , Rangnekar Vivek M , Byrd John C. , Muthusamy Natarajan , Bondada Subbarao
Published: October 2019

The most common human leukemia is B-cell chronic lymphocytic leukemia (B-CLL), which is characterized by a progressive accumulation of abnormal B-lymphocytes in blood, bone marrow and secondary lymphoid organs. Typically disease progression is slow, but as the number of leukemic cells increases, they interfere with the production of other important blood cells, causing the patients to be in an immunosuppressive state. To study the basis of this immunoregulation, we used cells from the transgenic Eμ-Tcl1 mouse, which spontaneously develop B-CLL due to a B-cell specific expression of the oncogene, Tcl1. Previously we showed that Eμ-Tcl1 CLL cells constitutively produce an anti-inflammatory cytokine, IL-10. Here we studied the role of IL-10 in CLL cell survival in vitro and the development of CLL in vivo. We found that neutralization of IL-I0 using anti-IL-10 antibodies or blocking the IL-10 receptor (IL-10R) using anti-IL-10R antibodies did not affect the survival of CLL cells in vitro. On the other hand, adoptively transferred Eμ-Tcl1 cells grew at a slower rate in IL-10R KO mice vs. wild type (WT) mice. There was a significant reduction in CLL cell engraftment in the spleen, bone marrow, peritoneal cavity and liver of the IL-10R KO compared to WT mice. Further studies revealed that IL-10 could be playing a role in the tumor microenvironment possibly by affecting anti-tumor immunity. This was seen by a reduction in the activation of CD8+ T cells as well as a significantly lower production of IFN-γ by CD4+ T cells purified from CLL-injected WT mice compared to those purified from CLL-injected IL-10R KO mice. These studies demonstrate that CLL cells suppress host anti-tumor immunity via IL-10 production. This led us to investigate possible mechanisms by which IL-10 is produced. We found a novel role of B-cell receptor (BCR) signaling pathway in constitutive IL-10 secretion. Inhibition of Src or Syk family kinases reduces the constitutive IL-10 production by Eμ-Tcl1 cells in a dose dependent manner. In addition, we found that Eμ-Tcl1 CLL cells exhibit clonal variation in their IL-10 production in response to BCR cross-linking. Further studies are being performed to understand the mechanisms by which BCR signaling affects IL-10 production.

Disclosures

No relevant conflicts of interest to declare.