bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decoding Gq Signaling in Platelets
Authors: Chen Xi , Gupta Shuchi , Cooper Matthew , Dehelian Daniel , Brass Lawrence F. , Ma Peisong 
Published: October 2019

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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.