bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Overexpressed P2X7 on Leukemia Progression in Mouse Acute Myeloid Leukemia Model
Authors: Feng Wenli , Yang Xiao , Wang Rong , Yang Feifei , Wang Hao , Liu Xiaoli , Wang Lina , Zheng Guoguang
Published: October 2019

P2X7 is one of the P2X family ligand-gated ion channel receptors. High level expression of P2X7 is reported in various malignant cells. High level expression of P2X7 was also detected in leukemia patients, especially in relapsed cases. A hyposensitive P2X7 mutant, N187D P2X7, was cloned from leukemia cells. However, the role of P2X7 on the progression of leukemia was poorly understood. In the present study, we studied the effects of P2X7 receptor in acute myeloid leukemia mouse model.

We established MLL-AF9 induced AML mouse model with high level expression of P2X7 (MA9-P2X7). High level of P2X7 significantly accelerated the progression of leukemia. Homing capability experiment demonstrated that MA9-P2X7 cells had lower homing potential. The apoptotic rate of freshly isolated leukemia cells had no significant difference between two groups. However, both in vitro culture experiments and in vivo BrdU incorporation assay demonstrated that MA9-P2X7 cells had enhanced proliferation potential, i.e. more S and G2/M phase cells but less G0/G1 phase cells. Moreover, upon treatment with Ara-C, though MA9-P2X7 cells were more sensitive to Ara-C, but the mice had shorter survival time. Furthermore, in vitro colony assay and limiting dilution transplantation experiments showed that MA9-P2X7 cells formed more colonies and had a 7.25-folds increase in LICs frequency. We also detected the expression of c-Kit, and the results showed that the majority of MA9-P2X7 cells were c-Kit+, whereas control cells have two populations and more than half of them were c-Kit-. Leukemia mice in MA9-P2X7 group had shorter survival time than those in the c-Kit+ control group.

Our results suggested that leukemia cells overexpressing P2X7 possessed the characteristics of both greater proliferation potential and higher LICs frequency, which contributed to the accelerated progression of leukemia.

This work was supported by grants 81570153, 81770183 and 81170511 from the National Natural Science Foundation of China (NSFC); programs 2016-I2M-2-006 and 2017-I2M-1-015 from the CAMS Innovation Fund for Medical Sciences (CIFMS); grant 17JCZDJC35000 from the Tianjin Natural Science Foundation; and Graduate Student Innovation Fund (2014-0710-1021) from Peking Union Medical College. Z.GG. is a recipient of the New Century Excellent Talents in University (NCET-08-0329).

Disclosures

No relevant conflicts of interest to declare.
Socioeconomic Status and Outcomes Among Mexican Patients Undergoing Allogeneic Stem Cell Transplantation
Authors: Leon Rodriguez Eucario , Rivera Franco Monica M
Published: October 2019

Background: Some specific patient and donor demographic factors have been described and associated with outcomes of hematopoietic stem cell transplantation (HSCT). However, associations with the socioeconomic status (SES) remain controversial as some studies including allogeneic HSCT (allo-HSCT) patients have reported that SES associates with worse long-term outcomes and other studies, including both, allogeneic and autologous HSCT have not found an association between SES and overall survival (OS), non-relapse mortality (NRM) or other outcomes. More importantly, these studies have been performed in developed countries and data from developing regions remains scarce.

Objective: To associate the SES with outcomes in Mexican patients undergoing allo-HSCT at a National Institute of Health located in Mexico City.

Patients and Methods: A retrospective study was performed including 124 consecutive patients undergoing allo-HSCT at the National Institute of Medical Sciences and Nutrition "Salvador Zubiran", from May 1999 to March 2018. SES was established according to the classification assigned by the Department of Social Work (levels I-VII); the lowest level corresponds to 7% out-of-pocket expense (93% subsidized by the Institution) and the highest to 120% (private health insurances). Patients were dichotomized into low SES (levels I-II) and high SES (levels ≥ III). Disease risk index was classified as low, intermediate or high using standard definitions and the HCT-CI score was assigned to each patient. Graft-versus-host disease (GVHD) was evaluated according to NIH guidelines. Endpoints included OS and NRM.

Results: Patient characteristics by SES are shown in Table 1. Age, educational attainment, employment status, and financial support were the sociodemographic characteristics that differed between both groups. There were no differences in GVHD between the two groups. For all the cohort, 30, 100-days, and 1-year NRM was 3.2%, 8.8%, and 14.5%, respectively. Figure 1 shows NRM and OS by SES group.

Conclusion: Although there were differences regarding diagnosis between the two groups (low and high SES), the DRI was the same between them, as well as the HCT-CI. Further, there were no differences between low and high SES in NRM or OS, demonstrating that our HSCT approaches are standardized and all patients can benefit from them despite their financial status, also highlighting that patients with low SES probably had good outcomes as a result of substantial governmental, NGO, and/or institutional subsidy.

Disclosures

No relevant conflicts of interest to declare.
Decoding Gq Signaling in Platelets
Authors: Chen Xi , Gupta Shuchi , Cooper Matthew , Dehelian Daniel , Brass Lawrence F. , Ma Peisong
Published: October 2019

Most platelet agonists work through G protein coupled receptors (GPCRs), activating pathways that involve members of the Gq, Gi, and G12 families of heterotrimeric G proteins. Gq is critical for most functional responses during platelet activation. A defect in Gq expression in patients leads to impaired platelet secretion and aggregation, which is associated with bleeding diathesis. We have previously shown that the Regulators of G protein Signaling (RGS) proteins function as negative regulators for platelet activation by limiting G protein-dependent signaling, but much remains to be learned about the mechanisms by which G proteins can be regulated during platelet activation.

Here we took advantage of an RGS-insensitive Gq(G188S) mutant mouse line to decipher the regulatory complex of Gq-dependent signaling in platelets. The G188S mutation disrupts RGS18 and Gq interaction in a way similar to what we have observed in an analogous Gi2(G184S) mutation. However, in contrast to increased platelet activation in Gi2(G184S) expressing platelets, G188S expressing platelets have decreased activation in response to thrombin, TxA2 and ADP, but not to collagen. The hemostatic thrombi formed in G188S mice are significantly reduced with constant embolization as compared with WT controls. Underlying these changes is a decrease in Gq-dependent signaling events, whereas shape change, which is G13-mediated, is unaffected. Our data further reveal that PLCβ3 and GRK2 complex with activated Gq, but not to Gi2. The G188S mutation in Gq not only prevents the binding of RGS proteins to Gq but also impairs the Gq/PLCβ3 interaction, though it does not affect the GRK2 binding to Gq. Instead, there an increase of GRK2 binding to Gq. Finally, the structural analysis shows that PLCβ3 shares a large overlapping binding area with RGS18 to Gq. Computational alanine scanning to predict binding interfaces indicates that the G188S mutation resides in a region important for the binding of both PLC and RGS. The PLC binding interface also overlaps with that of GRK2, which suggests that when PLC is in complex with Gq, it precludes the binding of both RGS proteins and GRK2. In the G188S mutant, however, PLC binding is reduced, which may reduce competition and allow more GRK2 to bind. The binding interfaces of RGS and GRK2 are not predicted to be overlapping, raising the possibility that the two proteins could bind simultaneously to activated WT Gq.

Collectively, these observations 1) indicate that the feedback mechanism of Gq inactivation in platelets is different from that of Gi2, 2) reveal, for the first time, that a Gq/PLCβ/RGS/GRK2 signaling node is present in platelets and plays an important role in Gq-dependent signaling during platelet activation, and 3) show that the G188S mutation affect Gq-mediated signaling by disrupting Gq/PLCβ/RGS interaction.

Disclosures

No relevant conflicts of interest to declare.
FAM46C Controls Antibody Production By the Polyadenylation of Ig mRNAs and Inhibits Cell Migration in Multiple Myeloma
Authors: Herrero Ana B , Dalia Quwaider , Corchete Sanchez Luis Antonio , Garcia-Sanz Ramon , Gutierrez Norma
Published: October 2019

FAM46C, which is frequently mutated in multiple myeloma (MM), has recently been shown to encode a non-canonical poly(A) polymerase (ncPAP). However, its target mRNAs and its role in MM pathogenesis remain largely unknown. Using CRISPR-Cas9 technology and gene expression analysis we found that inactivation of FAM46C in MM downregulates immunoglobulins (Igs) and several mRNAs encoding ER-resident proteins, including some involved in unfolded protein response (UPR), such as PDIA6, ERP44 and EDEM2, and others that affect glycosylation, such as SSR4, AGA and DDOST. We also found that FAM46C knockout cells exhibited lower ER stress than controls after treatment with tunicamycin, as indicated by RT-PCR analysis of spliced/unspliced forms of XBP1 mRNA. Interestingly, we show that FAM46C expression is induced during PC differentiation and that Ig mRNAs encoding secretory heavy and light chains are direct substrates of the ncPAP, as revealed by poly(A) tail-length determination assays. The absence of the ncPAP results in Ig mRNA poly(A) tail-shortening, leading to a reduction in mRNA and protein abundance. On the other hand, loss of FAM46C upregulated metastasis-associated lncRNA MALAT1 and results in a sharp increase in the migration ability of MM cells. This phenotype depends mainly on the activation of PI3K/Rac1 signaling in FAM46C knockout cells since treatment with specific inhibitors substantially reduces cell mobility. This finding may have significant therapeutic implications.

In conclusion, our results identify, for the first time, Ig mRNAs as targets of FAM46C, reveal an important function of this protein during PC maturation to increase antibody production, and suggest that its role as a tumor suppressor might be related with the inhibition of cell migration in MM.

Disclosures

Garcia-Sanz: Affimed: Research Funding.
Thalidomide Maintenance in Patients with Diffuse Large B-Cell Lymphoma after Autologous Stem Cell Transplantation: Single-Center Experience
Authors: Huang Hui-qiang , Bing Bai , Xiaoxiao Wang , Yan Gao , Li Pengfei , Qixiang Rong , Ping Li-qin
Published: October 2019

Introduction

At present, there is no standard of care for patients with relapsed/refractory non-Hodgkin lymphomas (NHL) after autologous stem cell transplantation (ASCT). Though, rituximab maintenance and interferon maintenance have been reported in patients with relapsed/refractory NHL after ASCT. Thalidomide is a kind of immunomodulatory drugs (IMiD) and has been proved to be effective in various NHLs, but the value of IMiD maintenance after ASCT remains to be discussed. In this study, we retrospectively analyzed the efficacy of thalidomide maintenance(TM) in patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) after ASCT, comparing with historical control of patients without TM.

Patients and Methods

Between January 2013 and December 2017, eighty-eight patients with relapsed/refractory DLBCL undergoing TM after ASCT at the Sun Yat-sen University Cancer Center (SYSUCC) were reviewed. As historical control, ninety-seven patients without TM after ASCT during January 2006 to December 2012 were compared for analyses. All patients achieved CR before ASCT. Patients with transplantation related deaths were excluded. TM were given 100mg daily for one year. If grade III toxicities were observed, thalidomide would be postponed for one week and reduced to 75mg daily, and further 50mg daily in case of recurrence of grade III toxicities. The latest follow-up was updated to June 30th, 2018. Clinical and laboratory information was collected and analyzed.

Results

Overall, a total of 185 patients were reviewed and 15 of them were excluded due to lost to follow-up. In the TM group(n=81) and the non-TM group(n=89) available for survival analyses, the median age were 44 years (range, 19-72) and 40 years (range, 17-76) respectively, the proportion of male were 55% and 62% respectively, and the median follow-up time were 24 months(range, 6-68 months) and 79 months(range, 5-160 months) respectively. The 3-year overall survival (OS) were 77.8% in the TM group and 64.0% in the non-TM group, respectively (P =0.037). The 3-year progression-free survival (PFS) were 69.8% in the TM group and 61.4% in the non-TM group, respectively. (P=0.094). In multivariate analysis, maintenance therapy was an independent prognostic factor for OS (P < 0.05) .

The major toxicities observed in the TM group were as follows: thrombocytopenia(73.2%), leucopenia(50.0%), constipation(53.5%), fatigue(58.5%), Somnolence (38.7%), rash(25.0%), edema(23.0%), and peripheral neuropathy(8.3%).

Conclusions

Despite the retrospective nature and other limitations of this study, it is suggested that TM might be associates with promising survival benefit of in patients with relapsed/refractory DLBCL after ASCT, comparing with historical controls. It warrants further prospective studies to confirm the efficacy of IMiD maintenance in DLBCL.

Figure. Figure.

Disclosures

No relevant conflicts of interest to declare.
Comprehensive Sequencing Identifies High Frequency of Copy Number Changes in Korean Patients with Acute Lymphoblastic Leukemia
Authors: Shin Sang-Yong , Kim Borahm , Lee Seung-Tae , Choi Jong Rak , Kim Sun-Hee
Published: October 2019

Acute lymphoblastic leukemia (ALL) is a genetically complex and heterogeneous disease with a wide range of genetic variations thus identified. As genomic profiling and sequencing studies have revealed genetic basis of ALL, a number of genetic variations are gaining clinical significance in connection with risk stratification and targeted therapy. With the need for comprehensive high-throughput analysis, next-generation sequencing (NGS) has become a good candidate for clinical testing. We have designed a comprehensive NGS assay to detect somatic mutations, translocations, and copy number changes and have evaluated its clinical utility in patients with ALL. The panel reliably detected single nucleotide variations (SNV) and copy number analysis was exceptionally helpful in identifying geneic and chromosomal deletions and duplications.

A total of 101 samples of 96 patients were tested. Those patients consist of 40 adults (median age 38, range 21-76) and 56 children (median age 6.5, range 0-17), and diagnoses include 76 B-ALLs and 20 T-ALLs. The most-frequently mutated gene was TP53 (7/96, 7.3%). Ras pathway were also frequently observed (21/96, 29%) in B-ALL and were associated with hyperdiploidy (P< 0.001). Mutations in PHF6, PTEN, FBXW7, JAK3 and WT1 were detected in patients with T-ALL, and all the variants were SNVs. PHF6 mutations were most common among T-ALL patients (7/20, 35%), followed by mutations in FBXW7 (5/20, 25%). Deletions outnumbered duplications, and the most frequently deleted was CDKN2A, followed by transcription factor genes including, IKZF1, PAX5, EBF1, and ETV6. IKZF1 deletion was more frequent in adults (P<0.005), and associated with BCR-ABL1 translocation (P<0.001). PAX5 deletion was also associated with BCR-ABL1 (P<0.001) and also observed in translocations representing Philadelphia-like ALL.

Fifty patients were with chromosomal abnormality detected by NGS, and some of them showed normal cytogenetics with a conventional method. Hyperdiploidy and interstitial deletion or duplication can be more easily detected; 11 cases were reclassified as B-ALL with hyperdiploidy, and numerical abnormalities and other copy number changes were identified in seven and 20 patients, respectively. Among 31 gene fusions identified by RT-PCR or NGS RNA fusion panel, only 17 (54.8%) were detected by DNA-based NGS testing.

Our NGS gene panel and bioinformatics tools showed excellent performance confirming the clinical utility in identification of important variants in patients with ALL. SNVs and CNVs could be identified simultaneously in a single assay, which could be an alternative or supplement for several conventional tests and simplify the testing processes. We found unexpectedly high proportion of CNVs in ALL, suggesting the need for intensive bioinformatics analysis for CNVs and careful interpretation.

Disclosures

No relevant conflicts of interest to declare.
Should Women with Sickle Cell Disease be Administered Prophylactic Transfusions to Avoid Complications during Pregnancy?
Authors: Palcu Patricia , Kuo Kevin H. M. , Ward Richard , Zaffar Nusrat , Malinowski Ann Kinga , Shehata Nadine
Published: October 2019

BACKGROUND: Increasing numbers of women with sickle cell disease (SCD) are reaching reproductive age. There is an array of possible pregnancy outcomes that women with SCD may experience. Many have described adverse maternal and fetal outcomes in pregnant patients with SCD including increased risk of pre-eclampsia, infections, painful vaso-occlusive crises as well as increased risk of intrauterine growth restriction, pre-term delivery and pregnancy loss. Not all women with SCD have complicated pregnancies, however. Limited data are available to categorize the proportion of patients who have uncomplicated pregnancies and protective characteristics for good pregnancy outcomes. Identifying these features potentially informs practice and reduces exposure to blood products as red blood cell (RBC) transfusion is associated with an increased risk of alloimmunization, particularly in pregnancy.

OBJECTIVE: To determine the proportion and characteristics of pregnant patients with SCD who have uncomplicated pregnancies.

METHODS: We retrospectively reviewed medical records of pregnant women with SCD from 1980 to 2018 at Mount Sinai Hospital, a university affiliated tertiary care centre in Toronto, Canada. We defined a pregnancy to be uncomplicated if the pregnancy was not associated with a hospitalization, RBC transfusion was not administered peripartum and/or the delivery was at term (37 or more weeks gestation).

RESULTS: A total of 179 pregnancies were included (Figure 1). Preliminary results show that 57% of pregnancies had hemoglobin SS disease. The median maternal age was 27 years (range 16-43 years) (n=179). Median hemoglobin concentration, platelet count and leukocyte count were 91g/L (n=141), 304 x 10(9)/L (n=140) and 11 x 10(9)/L (n=140), respectively. Hospital admission was required in 61% of pregnancies (n=171) and RBC transfusion in 49% of pregnancies (n=173). The median hemoglobin F level was 0.05 (range 0.01-0.87). Nineteen percent had coexisting alpha gene deletion (s). The median birth weight was 2863 grams (n=155). Analysis is ongoing to determine characteristics associated with the pre-defined pregnancy outcomes.

CONCLUSIONS: Women with SCD frequently have adverse maternal and fetal outcomes with pregnancy. However, 39% of pregnancies with SCD in this study did not require hospitalization and 51% did not require RBC transfusion. Additional analysis will attempt to identify protective features so as not to expose all patients to RBC transfusion unless it is required. These initial results suggest that risk scores should be developed for pregnant patients with sickle cell disease to identify who may benefit from RBC transfusion.

Disclosures

No relevant conflicts of interest to declare.
Decreased Physical Activity in Autologous Stem Cell Recipients Leads to Reduced QOL Scores during Hospitalization
Authors: Baldeo Candice , Moreno Vanegas Yenny , Khurana Sharad , Iqbal Madiha , Azzouqa Abdel-Ghani , Sher Taimur , Ailawadhi Sikander , Vishnu Prakash
Published: October 2019

INTRODUCTION:

Autologous hematopoietic stem cell transplantation can heavily impact the quality of life (QOL) of an individual. However, this procedure may be the only hope for a cure or a longer life for some individuals. When these patients develop severe neutropenia during transplantation, protective isolation is recommended to reduce the risk of infection. During protective isolation, patients may be confined to their hospital room which can decrease their physical activity.

For autologous hematopoietic stem cell receipts (AHSCR), severe neutropenia may last several days to weeks. During this time, patients often experience social isolation, emotional encumbrances and also physical deconditioning.Data is inconsistent whether protective isolation does reduce the incidence of infections.

In this study, we sought to investigate the impact of physical activity during hospitalization on Quality of Life in AHSCR with severe neutropenia using the Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT) questionnaire.

METHODS:

We conducted a prospective observational study of 15 patients admitted to Mayo Clinic Florida during November 2017 to May 2018 for autologous hematopoietic stem cell transplantation, wherein we monitored the activity of each patient during hospitalization by recording the number of steps taken each day by using an activity tracker worn by the patient. Informed consent was obtained on admission before enrolling patients. Patients completed a Quality of Life (QOL) questionnaire (FACT-BMT version 4) on admission and prior to discharge from the hospital.

RESULTS:

Of the 15 patients that were enrolled, 5 walked ≤ 100 steps/day (group A, median, 71) and 10 walked > 100 steps/day (group B, median, 406). While there was no difference in the median time to engraftment and length of hospital stay, the mean QOL score decreased from 89.2 on admission to 81.4 on discharge in less active neutropenia patients compared to the ones who were more active. (Table 1; Figure 1)

CONCLUSION:

Lack of physical activity decreases QOL in AHSCR. During hospitalization, AHSCR should be encouraged to increase their activity to improve QOL. Having an activity tracker may make it easier for patients to monitor their activity, and thus lead to a better QOL.

Figure. Figure.

Disclosures

Sher: Affimed: Research Funding. Ailawadhi:Pharmacyclics: Research Funding; Janssen: Consultancy; Takeda: Consultancy; Amgen: Consultancy; Celgene: Consultancy.
Role of G-CSF after High-Dose Post-Transplantation Cyclophospamide
Authors: Elayan Mohammed M , Bachier Carlos R. , Battiwalla Minoo , Siler Darby
Published: October 2019

Background

High-dose post-transplantation cyclophosphamide (PTC) has proven to be a valuable treatment modality for the prevention of graft-versus-host disease (GVHD) after stem cell transplant (SCT). Granulocyte colony stimulating factor (G-CSF) is routinely given after PTC to improve time to engraftment. Historically, based on the Johns Hopkins regimen, G-CSF is given on Day +5 post-SCT. However, this strategy has not been vigorously compared to other dosing strategies. We sought to assess the effect of delayed (Day +10) or omitted administration of G-CSF on various post-SCT outcomes.

Methods

Allogeneic SCT patients receiving PTC at standard dosing of 50 mg/kg daily on Days +3 and +4 were included in this retrospective analysis. G-CSF was given at the labeled dose of 5 mcg/kg (rounded to nearest vial) on Day +10 for 15 consecutive patients then omitted entirely for ten consecutive patients. These results were compared to historical controls that received G-CSF beginning Day +5 after PTC. All patients received antimicrobial prophylaxis with levofloxacin, acyclovir and posaconazole. The primary outcome was to determine time to engraftment defined, as an absolute neutrophil count ≥500, in each group. A complete list of secondary outcomes is below and includes febrile neutropenia and infection rates, incidence of acute GVHD, as well as survival and relapse rates.

Results

Forty-eight patients receiving PTC were included in the final analysis. Patient characteristics and outcomes are described in Table 1. There were no significant differences between the three groups with the exception of cells infused (p=0.03). While there was a longer time to ANC engraftment for patients not receiving GCSF after PTC, this was not statistically significant. Acute GVHD and first year outcomes were unable to be determined at this time for patients not receiving GCSF due to this population not reaching these endpoints at time of submission.

Conclusion

Administration of G-CSF after post transplant cyclophosphamide is not associated with earlier neutrophil engraftment. Secondary endpoints including platelet engraftment, aGVHD, incidence of febrile neutropenia, or infections were similar among all groups. A larger, randomized study is needed to confirm these results.

Disclosures

Bachier: Sanofi: Speakers Bureau; Seattle Genetics: Speakers Bureau.
A Retrospective Study of 108 Cases of Relapsed or Refractory Classical Hodgkin Lymphoma: Second Line Therapies and Autologous Hematopoietic Stem Cell Transplantation
Authors: Yang Mingzi , Wu Meng , Nuersulitan Reyizha , Liu Yanfei , A Liya , Ping Lingyan , Song Yuqin , Zhu Jun
Published: October 2019

Objective: To investigate the efficacies of different second-line therapies and outcomes of relapsed or refractory (R/R) classical Hodgkin lymphoma (cHL).

Methods: From 2008 to 2017, 108 R/R cHL patients received second line therapies at Lymphoma Department of Peking University Cancer Hospital. We retrospectively reviewed the clinical data and outcomes.

Results: Among 108 patients, 74 (68.5%) were male. At the time of cHL diagnosis, the median age was 28 years; 48 (44.4%) patients were stage Ⅰ-Ⅱ and 60 (55.6%) patients were stage Ⅲ-Ⅳ. 79 (73.1%) patients were primary refractory while 29 (26.9%) patients relapsed after initial therapy. The overall response rate (ORR) of 108 cases was 66.7% of second-line salvage therapy. Only 29 (26.9%) patients achieved complete remission (CR). 20 patients achieved CR or PR at two cycles of salvage therapy but developed progressive disease after four cycles. 82 (75.9%) patients received DICE regimen (dexamethasone, ifosfamide, cisplatin and etoposide) or ICE regimen (ifosfamide, carboplatin and etoposide) as salvage therapy, 11 (10.2%) patients received ABVD regimen (adriamycin, bleomycin, vincristine, dacarbazine) or BEACOPP regimen (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone), 12 (11.1%) patients received GemOx regimen (gemcitabine and oxaliplatin) or GDP regimen (gemcitabine, cisplatin and dexamethasone), 3 (2.8%) patients received other chemotherapy. The ORR of DICE/ICE, ABVD/BEACOPP and GemOx/GDP group were 72%, 81.8% and 16.7% (p=0.001). With a median follow-up time of 34 months, the 3-year overall survival (OS) rate and 3-year progression-free survival (PFS) rate of all patients were expected to be 83% and 58.5%. The 3-year OS rate of DICE/ICE, ABVD/BEACOPP and GemOx/GDP group were 83.2%, 81.8% and 71.3% (p=0.572). The 3-year PFS rate of DICE/ICE, ABVD/BEACOPP and GemOx/GDP group were 63.7%, 63.6% and 40% (p=0.157). 60 (55.6%) patients received autologous hematopoietic stem cell transplantation (AHSCT) and 3-year OS was 90.4%, which showed a significant survival improvement as compared with patients without AHSCT (3-year OS 72.6%, p=0.013).

Conclusion: In this study, DICE/ICE regimen as second-line salvage therapy for R/R cHL was more effective than GemOx/GDP regimen. AHSCT could significantly improve survival of R/R cHL.

Disclosures

Song: Peking University Cancer Hospital (Beijing Cancer Hospital): Employment. Zhu:Beijing Cancer Hospital: Employment.
Brain Magnetic Resonance Imaging and Angiography Findings in Ugandan Children with Sickle Cell Anemia; A Cross Sectional Study
Authors: Idro Richard , Green Nancy S. , Munube Deogratias , Buluma Linda Rosset , Kebirungi Bridget , Opoka Robert , Bangirana Paul , Mupere Ezekiel , Kayongo Edward , Sekibira Rogers , Kasirye Philip , Lubowa Samson K. , Kawooya Michael , LaRussa Phillip , Minja Frank
Published: October 2019

Sickle Cell Anemia (SCA) is a leading cause of childhood stroke in sub-Saharan Africa and sickle cell brain vasculopathy manifests either as overt stroke or clinically "silent infarcts". This study aimed to describe brain abnormalities seen on magnetic resonance imaging in Ugandan SCA children. Our hypothesis was that multi-model abnormalities would be associated with cerebrovasculopathy found on MRI/MRA.

Methods

As part of a larger study to determine the burden and spectrum of neurological and cognitive impairments in SCA children in Uganda, we selected 81 children ages 1-12 years with HbSS, a sample enriched for possible brain pathology from Mulago hospital SCA clinic out of a random sample of 265 stable children. None was receiving hydroxyurea. All had detailed clinical history, and physical, neurological and cognitive testing, trans-cranial Doppler (TCD) cerebral blood flow velocity determination and non-contrasted brain MRI/MRA using a 1.5 Tesla scanner. Cognitive testing was performed using age-specific tools validated for Ugandan children.

Results

Of the 81 participants imaged, 61 had one or more of history of stroke, an abnormal neurological exam, cognitive impairment or abnormal TCD, while 20 had normal test results. MR abnormalities were seen in 35/61 (63.9%) participants with probable brain pathology and in 4/20 (20.0%) without any probable brain pathology. They included different structural abnormalities seen in all brain regions ranging from only T2 weighted hyper-intensities, white matter lacuna infarction to bilateral ischemic and multi-focal cerebral infarcts with associated compensatory hydrocephalus. MRA abnormalities ranged from cerebral microangiopathy to multiple stenosis and occlusions of major arteries, including moya-moya in 4 subjects. Severe vessel obstructions were also seen in multiple young children <36 months.

Conclusions

Brain injury in Uganda children with SCA begins early in childhood and becomes a common finding during later childhood. Early screening for stroke and intervention therapy is warranted to prevent sickle brain vasculopathy initiated early after diagnosis. The risk factors for such early brain injury should be investigated.

Disclosures

No relevant conflicts of interest to declare.
MLL-USP2: An Underestimated New Entity of MLL-Rearranged Leukemia Identified By NGS Analysis
Authors: Meyer Claus , Lopes Bruno , Caye-Eude Aurélie , Cavé Hélène , Arfeuille Chloé , Sutton Rosemary , Venn Nicola , Larghero Patrizia , Oh Seung Hwan , Tsaur Grigory , Zaliova Marketa , Zuna Jan , Juvonen Vesa , Panzer-Grümayer Renate , Fazio Grazia , Cazzaniga Giovanni , Emerenciano Mariana , Marschalek Rolf
Published: October 2019

Chromosomal rearrangements of the MLL gene are responsible for 5-10% of all acute leukemias, biphenotypic leukemias and myelodysplastic syndromes. The large number of known MLL fusions (>80) renders a precise diagnosis a demanding task. Even though all MLL rearrangements are associated with high-risk acute leukemia, the outcome (poor or very poor) is influenced by the partner gene. The applied diagnostic methods (LDI-PCR and multiplex PCR) allows the identification of MLL fusion genes at the nucleotide level, providing important information on the genetics of leukemia patients, and patient-specific biomarkers. These biomarkers are used for monitoring of minimal residual disease in acute leukemia patients during and after therapy. Thus, the identification of MLL gene fusions is necessary for rapid clinical decisions to determine the best therapy regimen.

We have developed a customized NGS panel for MLL diagnostics to utilize state of the art technology at DCAL. With this new tool, the whole MLL gene is analyzed in contrast to the LDI-PCR where only the main MLL breakpoint cluster region (BCR-1) is covered. The first results of the NGS analysis of 84 patients identified MLL breakpoints located outside the main BCR-1 of MLL. Furthermore, a novel MLL partner gene USP2 was identified in 16 patients. All MLL-USP2 positive patients had a breakpoint located outside BCR-1 and within a newly defined breakpoint cluster region BCR-2. The BCR-2 site was also used in 2 other patients with MLL-AFF1 and one patient with MLL-MLLT3.

These findings reveal USP2 as a new entity for MLL rearrangements affecting indifferently children aged 3 months to 10 years old (mean 30 months) with no gender bias (M/F=1.3). Interestingly, only 5/16 affected children were below 1 year of age at diagnosis and thus treated according to the Interfant trial. Clinical presentation as well as outcome associated with this new entity deserves further investigation to define whether those patients should be allocated, as other MLL-rearranged ones, in high-risk treatment groups. More MLL patients should also be analyzed to get a better idea of the frequency of breakpoints within BCR-2, especially the frequency of MLL-USP2 fusions. Indeed, standard FISH analysis and CGH array do not permit reliable detection of this fusion, explaining why they remained undetected so far. The biology of this novel MLL rearrangement also deserves further investigation, considering that USP2 is the only MLL partner fused exclusively to BCR-2.

Disclosures

No relevant conflicts of interest to declare.
Health-Related Quality of Life (HRQL) Trajectories during Treatment for Advanced Stage Pediatric Hodgkin Lymphoma (HL)
Authors: Parsons Susan K , Rodday Angie Mae , Bush Rizvan , Pei Qinglin , Waheed Anem , Keller Frank G , Kelly Kara M. , Henderson Tara O. , Castellino Sharon M.
Published: October 2019

Introduction: The treatment of advanced stage HL typically includes dose-dense chemotherapy with or without involved field radiation. However, little is known about the HRQL of pediatric patients during initial treatment. We describe the HRQL trajectory over time by child and parent-proxy rater and examine baseline patient characteristics associated with the trajectory.

Methods: Children and adolescents, ages 5-17.9 years newly diagnosed with advanced stage HL and enrolled in Children's Oncology Group AHOD 1331, and their parents were co-enrolled in an embedded study to assess HRQL (n=310). Children (age ≥11 years) and parent proxies (of children 5-17.9 years) reported on the child's global HRQL using the Child Health Rating Inventories (CHRIs) at four times: (1) baseline, (2) cycle 2, (3) cycle 5, and (4) end of therapy, approximately 6-7 months following initial diagnosis. The 7-item CHRIs-Global yields scores that range from 0-100, with higher scores indicating better HRQL. A repeated measures linear regression model was fit with categorical time (reference, baseline), rater, child race, ethnicity, and continuous age. An interaction of rater and time was tested and predicted means were plotted.

Results: 97% of age-eligible patients and parents completed baseline HRQL assessments with 93% completing planned follow-ups. Median child age was 15.5 years (q1=5.4, q3=18.9) and 50.3% were female. Most children were white (76.1%) and non-Hispanic (82.6%). There was no significant interaction between rater and time (Figure), so this was subsequently excluded from the model. Scores improved slightly at time 2 (β=2.5, 95%CI=0.3, 4.6) and 3 (β=2.8, 95%CI=0.3, 5.3) compared to baseline; larger improvements were seen by time 4 (β=10.6, 95%CI=7.9, 13.3) after completion of therapy. Children reported higher HRQL than their parent proxies (β=5.6, 95%CI=3.9, 7.2), males had higher HRQL than females (β=4.6, 95%CI=1.0, 8.3), and older age was associated with lower HRQL (β=-0.8, 95%CI=-1.5, -0.1). There was no significant effect of race or ethnicity.

Conclusions: Completion rates of HRQL were high across all time periods and for both raters. HRQL, impaired at baseline, likely from the disease process, improved slightly during treatment, with larger improvements by the end of initial therapy. Future research will examine how clinical and treatment factors impact the HRQL trajectory.

Figure. Figure.

Disclosures

Parsons: Seattle Genetics: Research Funding. Rodday:Seattle Genetics: Research Funding. Henderson:Seattle Genetics: Research Funding.
Hypercalcemia- Leukocytosis Syndrome: A Rare Ominous Indicator in Lung Cancer
Authors: Hanson Taylor , Patel Ravi , Sahu Nitasa , Ayaz Zain , Caler Julie , Jones Kirk , Jain Rohit
Published: October 2019

Introduction:

Paraneoplastic syndromes are signs and symptoms that occur in association with malignancy at sites distant from the primary tumor or metastases. They occur in approximately 10% of patients with lung cancer (1).

Case:

A 59-year-old male with a history of tobacco abuse, COPD, and Stage IV Lung Adenosquamous cancer with brain metastases status post chemotherapy presented with weakness and lethargy. Patient was normotensive and on room air. Clinical exam was significant for confusion with noted chronic cachexia. Labs most prominent were a WBC count of 46.8 (16.3 1mo prior, 44.6 3wks prior) , Cr of 1.9, Ca of 11.9 , and Lactic acid of 3.7. Imaging was consistent with an increase in his RUL cavitary lesion with pleural based lesions and 11 metastatic deposits throughout the brain. He was admitted and started on aggressive intravenous fluids. Furthermore, infectious workup was initiated and empiric antibiotics administered for possible pneumonia. By day 3 of admission his creatinine, calcium, and lactic acid normalized but his wbc continued to trend up to 98.6 despite negative infectious workup. His severe metastatic disease burden along with his failure to thrive carried a poor prognosis. Subsequently, a family meeting was held and he was transitioned to comfort measures. Patient passed away shortly thereafter.

Discussion:

The case clearly demonstrates poor prognostic indicators with hypercalcemia and severe leukocytosis in the setting of end stage lung adenosquamous carcinoma. Classically, paraneoplastic hypercalcemia is associated with PTHrP production in Squamous Cell carcinoma. Overall incidence of hypercalcemia in lung cancer ranges from to 8%-12% with median survival time (MST) of 3.8 months (1,2).Paraneoplastic Leukocytosis meanwhile is most often associated with adenocarcinoma (42%) and squamous cell carcinoma (36%) with incidence ranging between 16 and 30% and MST of 1.9 months (1,2). Nonetheless, the combination of these two known as Hypercalcemia-Leukocytosis syndrome has been identified an independent clinical entity with an even shorter median survival time in comparison with leukocytosis or hypercalcemia alone of 1.5 months (2). The incidence of this was studied to be 0.5% over a 10 year interval (2). Given this rare occurrence, it is prudent for clinicians to recognize this clinical syndrome and the very poor prognosis it bears .

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4127595/

G.R. Mundy, K.J. Ibbotson, S.M. D'Souza, E.L.Simpson, J.W. Jacobs, T.J. MartinThe hypercalcemia of cancer. Clinical implications and pathogenic mechanismsN Engl J Med, 310 (1984), pp. 1718-1727

.https://www.sciencedirect.com/science/article/pii/S0169500203004549?via%3Dihub Hypercalcemia-leukocytosis syndrome associated with lung cancer

Disclosures

No relevant conflicts of interest to declare.
Regulatory T Cells Control PF4/Heparin Antibody Production in Mice
Authors: Zheng Yongwei , Zhu Wen , Haribhai Dipica , Williams Calvin B. , Aster Richard H. , Wen Renren , Wang Demin
Published: October 2019

Heparin-induced thrombocytopenia (HIT) is an immune-mediated disorder that can cause fatal arterial or venous thrombosis/thromboembolism. Immune complexes consisting of heparin, platelet factor 4 (PF4) and PF4/heparin-reactive antibodies are central to the pathogenesis of HIT. Regulatory T (Treg) cells are a subpopulation of CD4 T cells that modulate immune system by suppressing or down-regulating immune response and play an important role in immune homeostasis. However, the role of Treg cells in controlling PF4/heparin-specific antibody production is not known. Here we found that FoxP3-deficient mice, which have no functional Treg cells, spontaneously generated PF4/heparin-specific antibodies as early as three weeks after birth. Similarly, following transplantation with bone marrow cells from FoxP3-deficient mice, Rag1-deficient mice that have no endogenous B cells and T cells spontaneously produced PF4/heparin-specific antibodies. In contrast, Rag1-deficient mice that received wild-type bone marrow cells failed to produce PF4/heparin-specific antibodies. In addition, adoptively transferred Treg cells prevented spontaneous production of PF4/heparin-specific antibodies in FoxP3-deficient mice. Adoptively transferred Treg cells, not conventional CD4 T cells, also suppressed PF4/heparin complex-induced production of PF4/heparin-specific IgGs in wild-type mice. Treg cells suppress immune response mainly through releasing anti-inflammatory cytokines, such as interleukin-10 (IL-10). Deficiency of IL-10 led to spontaneous production of PF4/heparin-specific antibodies in mice. Moreover, BM chimeric mice with CD4 T cell-specific deletion of IL-10 increased PF4/heparin-specific IgG production following PF4/heparin complex challenge. Taken together, these findings demonstrate that Treg cells play an important role in suppressing PF4/heparin-specific antibody production in mice.

Disclosures

Haribhai: AbbVie Inc.: Employment. Aster:BloodCenter of Wisconsin: Patents & Royalties.
Diverse Bloodstream Pathogens Are Identified in the Gut Microbiome Prior to Infection in Hematopoietic Stem Cell Transplantation Recipients
Authors: Andermann Tessa M , Tamburini Fiona , Tkachenko Ekaterina , Senchyna Fiona , Banaei Niaz , Bhatt Ami S.
Published: October 2019

Recipients of hematopoietic stem cell transplantion (HCT) are at high risk for bloodstream infections (BSI); culture-based and marker gene sequencing approaches have been previously applied to interrogate the intestine as a reservoir of these pathogens. Identifying the source of bloodstream infections can impact infection control and prevention practices such as removing central venous catheters and placing patients in isolation. To evaluate the genomic concordance of bloodstream pathogens and bacterial strains within the intestinal microbiome, we developed StrainSifter (Figure 1), a streamlined bioinformatic pipeline using whole genome shotgun sequencing to compare nucleotide variation between bacterial isolate strains and metagenomes. We applied StrainSifter to bloodstream isolates and stool metagenome samples from a cohort of 30 HCT recipients with bloodstream infections at a single academic center. StrainSifter is designed to 1) identify single nucleotide variants (SNVs) between isolate and metagenomic short reads aligned to assembled draft genomes using stringent alignment, coverage, and variant frequency criteria, and 2) output both phylogenetic trees and SNV counts for clinical and epidemiologic strain typing and comparison. Using StrainSifter, we identified enteric BSI isolates - including Enterococcus faecium, Klebsiella pneumoniae, Escherichia coli, and Streptococcus mitis - that were identical or nearly identical with those in the gut microbiota. We also identified highly concordant strains of Staphylococcus epidermidis and Pseudomonas aeruginosa between the bloodstream and gut microbiome, an unexpected finding for typically non-enteric organisms. Although intestinal domination by pathogenic bacteria preceded BSI with E. faecium and E. coli as previous studies have demonstrated, we found significant heterogeneity in the relative abundance of pathogens prior to infection for other bacteria. These findings demonstrate the utility of StrainSifter in strain matching between isolate and metagenomic sequencing data, and provide a more precise and comprehensive investigation of the intestine as a potential reservoir of diverse pathogens capable of causing bloodstream infections in HCT recipients. These findings may have implications for the tracking and prevention of BSI previously classified as central-line associated bloodstream infections.

Disclosures

No relevant conflicts of interest to declare.
Development of Potency Assays for Quality Assessment of an Advanced Therapy Medicinal Product: Mitomycin C-Induced Peripheral Blood Mononuclear Cell (MIC) Product
Authors: NI Ming , Wang Lei , Kleist Christian , Terness Peter , Opelz Gerhard , Morath Christian , Schaier Matthias , Müller-Tidow Carsten , Zeier Martin , Schmitt Michael , Schmitt Anita
Published: October 2019

Introduction:

Quality assessment in terms of product specificity and product potency is obligatory and strictly required by EMA and FDA to provide a platform for analysis of product comparability, stability and compatibility, and for clinical development to help predict product clinical efficacy. Mitomycin-treated donor peripheral blood mononuclear cells (MICs) could induce donor-specific tolerance via generation of recipient-derived tolerogenic dendritic cells (tDCs). To evaluate the immunomodulating capacity of the MIC product, we assessed the phenotype of tDCs, the immunosuppressive capacity of tDCs on allo-reactive CD4+ and CD8+ T cells as well as on CMV-specific CD8+ T cells.

Methods:

For standardization of the potency assay, third-party PBMCs positive for HLA-A2 and anti-CMV IgG were used. Immature DCs (iDCs) were generated 3 days before MIC production. MICs were generated under Good Manufacturing Practice (GMP) conditions. Each batch of MICs was introduced to iDCs at different ratios (1:0, 1:1, 1:10, 1:20) for a two-hour interaction followed by adding a DC maturation cocktail for overnight co-culture. Thereafter tDCs were purified by magnetic negative separation. The morphology of tDCs was observed by microscopy. The expression of HLA-DR, CD80, CD83, CD86 and CD103 was analyzed by flow cytometry. The inhibitory capacity on allo-reactive T cells and virus specific T cells was determined by mixed lymphocyte reaction (MLR) assay, by ELISpot assay and by Tetramer staining assay after one week of expansion in mixed lymphocyte peptide culture (MLPC).

Results:

In light microscopy (magnification: x 40), tDCs showed a relative smooth membrane surface. While the conventional mDCs were significantly larger in size with rough surface, richer ruffles on the cell membrane, and bigger, longer protrusions or pseudopodia. MIC products could inhibit the expression of costimulatory molecules on tDCs with an inhibition of 41% of CD80, 27% of CD83 and 23% of CD86. In parallel, the inhibitory marker CD103 was up-regulated about 65% on tDCs. Functionally, both tDCs and MICs could inhibit the IFN-γ secretion by CMV-specific CD8+ T cells, respectively. Moreover, the proliferation of allo-reactive T cells and CMV-specific T cells could be inhibited by tDCs and MICs.

Conclusions:

In summary, the potency assays, including the measurement of physicochemical parameters, the morphology and marker expression of tDCs, as well as the biologic characterization, the functionally immunosuppressive capacity of tDCs, comprise valuable parameters for the evaluation of clinically used advanced therapeutic cellular products.

Disclosures

No relevant conflicts of interest to declare.