bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic Disruption of the SH3 and SAM Domains of HACS1 Enhances Adaptive Immunity.
Authors: Wang Dingyan , Stewart A. Keith , Zhuang Lihua , Xiao Nancy , Hlaing Mawmaw , Shi Changxin , Zhu Yuanxiao , Wang Youdong , Wen Xiao-Yan 
Published: April 2020

Abstract
HACS1 is a SH3 (Src homology 3) and SAM (sterile alpha motif) domain containing adaptor protein that is expressed in activated B and dendritic cells, is up-regulated by Interleukin 4 in the process of B cell activation and likely serves to dampen the immune response. To elucidate the function of HACS1, we generated HACS1 gene knockout mice by deletion of the SH3 and SAM domains. HACS1−/− mice were viable and fertile and had normal bone marrow B cell development and normal splenic T and B cell populations. However, adult HACS1−/− mice had increased numbers of peritoneal B1 cells (IgM+CD5+). Upon LPS plus BCR or TCR stimulations, splenic cells from HACS1−/− mice demonstrated an upregulation of activation markers with increased intensity of CD23 expression or increased population of CD69 positive cells. Purified B220+ splenic B cells from HACS1−/− mice showed increased cell proliferation upon BCR stimulation. Both T helper type 1 (Th1) and T helper type 2 (Th2) humoral responses were enhanced in HACS1−/− mice upon immunization with T cell-dependent antigen NP-KLH, which resulted in increased production of interferon-gamma (IFN-γ), anti-NP IgG2a and IL-4, as well as anti-NP IgG1 and IgE. Upon immunization with T cell-independent antigens such as TNP-LPS and TNP-Ficoll, HACS1−/− mice had increased production of anti-TNP IgM and IgG3 as compared to normal controls. The in vitro maturation of bone marrow-derived dentritic cells from HACS1−/− mice was similar to wild-type mice but HACS1−/− dentritic cells showed increased IL-12 production upon stimulation with anti-CD40 or LPS. There was no significant difference in antigen uptake by cultured dentritic cells from non-immunized wild-type or knockout mice. However, in immunized mice, an increase in antigen uptake in HACS1−/− dentritic cells was observed. We further demonstrate that the HACS1−/− B cells had increased tyrosine phosphorylation in the resting state. As deletion of the SH3 & SAM domains of HACS1 appears to generate a hypersensitive immune response, our results collectively support that HACS1 negatively regulates adaptive immunity.
The CD22 Epitope, Dose, Dosing Interval, and Timing All Effect Efficacy of Anti-CD22 mAb-Based Therapy of NHL.
Authors: O’Donnell Robert , Pearson David , McKnight Hayes , Tedder Thomas , Tuscano Joseph M. 
Published: April 2020

Abstract
Rituximab, a chimeric anti-CD20 monoclonal antibody (mAb) has become integral to non-Hodgkins lymphoma therapy. New, clinically effective, anti-NHL mAb may further improve outcomes. CD22 is a B-lymphocyte-specific adhesion molecule on the surface of most NHL, so it is a promising target for immunotherapy. A panel of anti-CD22 mAbs were developed and tested. Anti-CD22 mAbs that bind the two NH2-terminal immunoglobulin domains of CD22 and specifically block the interaction of CD22 with its ligand were identified. CD22-blocking mAbs induce apoptosis in neoplastic B-cells and are functionally distinguishable from other anti-B-cell, and even other anti-CD22 mAbs. MAbs that do not block ligand-binding have only modest functional effects. HB22.7 is the blocking anti-CD22 mAb chosen for study and characterization in a Raji NHL-bearing nude mouse model. The goal of this study was to characterize the dose, route and schedule of administration that can guide the translation of HB22.7 to a clinical trial. In addition to untreated Raji-bearing nude mice, a control, non-blocking mAb (HB22.27) was compared to HB22.7. The non-blocking mAb had minimal pre-clinical efficacy, whereas HB22.7 improved survival and caused substantial tumor shrinkage. Varying doses of HB22.7 were tested; doses greater than 1.4 mg did not further increase efficacy (or toxicity). An important consideration regarding translation of HB22.7 to clinical trials is the size of tumors to be treated. In this study, tumors less than 200 mm3 had a much higher response rate than did larger tumors. Varying schedules of HB22.7 administration (1.4 mg/dose) were tested; one dose every other week was more effective than more or less frequent dosing. Immuno-PET showed that NHL was effectively and specifically targeted when copper-64-labeled HB22.7 was administered either intravenously or subcutaneously. This study provided preclinical data as to a useful dose, route and schedule of administration of the anti-CD22 mAb, HB22.7
RB1 Haploinsufficiency Confers a Proliferation Advantage in Myeloma Cell Lines.
Authors: Henry Travis J. , Chng Wee Joo , Carpten John , Bergsagel P. Leif , Fonseca Rafael 
Published: April 2020

Abstract
The retinoblastoma 1 (RB1) gene is a frequent target of mutation or inactivation in neoplastic diseases. However, the current model for RB1-mediated malignancy requires inactivation of both alleles for tumor progression. Single–copy loss of RB1 has been shown to correlate with an approximate 50% reduction in RB1 mRNA expression in patients diagnosed with multiple myeloma and survival in this cohort of patients is significantly reduced. Using siRNA to reduce Rb protein levels to 50% and Rb-expressing adenovirus to restore RB1, variations in proliferation and cell cycle were observed. The KMS–11 adherent cell line with normal Rb protein expression was labeled with carboxyfluorescein succinimidyl ester (CFSE) for tracking of cellular division and RB1 siRNA added to silence 50% of protein expression. Transfection efficiency for siRNA was measured at 95% or greater. Flow cytometric analysis was performed at 72 hours to identify changes in proliferation between controls and Rb knock–down. Using CFSE proliferation analysis software, reduction of Rb protein levels by 50% caused an average increase in the proliferation index from 2.05 to 2.50. Additionally, reduction of Rb protein levels caused an increase in the percentage of cells in S–phase, from 24 to 29%. CFSE and cell cycle experiments were performed in triplicate. Conversely, addition of Rb–expressing adenovirus to MM.1R and U266 cell lines, with mono-allelic and bi-allelic loss of RB1 respectively, resulted in a decrease in proliferation assayed by CFSE and an average decrease in the percentage of cells in S-phase from 29 to 23% compared to controls. No changes in proliferation or cell cycle compared to untreated controls were observed following null adenovirus infection. Western blot and quantitative RT–PCR (qPCR) were used to confirm reduction or addition of RB1 to cell lines. Further, qPCR was used to identify potential activation of the interferon response following addition of siRNA and adenovirus. No changes in annexin V expression were observed following reduction or replacement of Rb as compared to controls. These results suggest the addition of proliferation advantages to tumors with single copy loss of RB1. For malignancies such as multiple myeloma characterized by deletion of 13q14 coupled with an extended period of development, the proliferation advantage associated with RB1 haploinsufficiency may contribute to decreased survival in the deletion 13 cohort.
Ribosomal Proteins Are Overexpressed in Hyperdiploid Multiple Myeloma.
Authors: Weinhold Niels , DeVos John , Hose Dirk , Rossi Jean-Francois , Axel Benner , Mahtouk Karène , Raab Marc S. , Rème Thierry X. , Jauch Anna , Moreaux Jerome , Pantesco Veronique , Goldschmidt Hartmut , Jourdan Eric , Cremer Friedrich W. , Klein Bernard , Moos Marion 
Published: April 2020

Abstract
Multiple myeloma (MM) is proposed to consist of two main pathogenetic groups. While hyperdiploidy (HD) is characterized by multiple trisomies of odd-numbered chromosomes (i.e. 3, 5, 9, 11, 15, and 19), non-hyperdiploid MM (NHD) show frequently one of the several recurrent IgH-translocations. The aim was to compare HD versus NHD by gene expression profiling (GEP). CD138-positive multiple myeloma cells from 74 newly diagnosed MM patients (42 GEP training group (TG), 32 GEP validation group (VG)) were purified by autoMACS-sorting. Sorted cells were analyzed by interphase-FISH with probes specific for 6q21, 8p21, 9q34, 11q23, 13q14, 15q22, 17p13, 19q13 and translocations t(4;14) and t(11;14). HD and NHD were defined by using a copy number score (CS), which was calculated by subtracting the number of probes indicating losses from the number of probes detecting additional copies (CS &gt;0: HD; CS ≤0: NHD). GEP was performed with Affymetrix DNA-microarrays. Nearest shrunken centroid classification (NSCC) was used to discriminate the different groups, using GCRMA-normalized gene expression values. The prediction error was estimated by means of nested cross-validation using 10 repetitions of 10-fold cross-validation within the training set and separately calculated by use of the NSCC classifier of the training set to predict the validation set. Goeman’s global test was used to check the influence of ribosomal protein expression between HD and NHD. In the TG, both HD and NHD were found in 21 patients. The VG comprised 13 patients with NHD and 19 patients with HD. NSCC resulted in a predictor for HD versus NHD of 81 probe sets with a cross-validated misclassification rate of 14.2% for the TG and 26.5% for the VG. Three of the top ten genes were ribosomal proteins, overexpressed in patients with HD. Goeman’s global test further showed that ribosomal proteins are overexpressed in HD (TG: p&lt;0.001; VG: p=0.03). Interestingly, ribosomal protein genes located on even-numbered chromosomes were also overexpressed. In conclusion, overexpression of ribosomal proteins independent of their location on odd- or even-numbered chromosomes indicates more than just a gene dosage effect and therefore a pathogenetic role of the upregulation of the ribosomal machinery in HD.
The JAK2-V617F Mutation Load Remains Stable over Several Years in Most Patients with Myeloproliferative Disorders Analyzed in a Retrospective Single Center Study.
Authors: Theocharides Alexandre , Looser Renate , Hui Hao-Shen , Buser Andreas S. , Gratwohl Alois , Tichelli Andre , Skoda Radek C. 
Published: April 2020

Abstract
An acquired somatic mutation in the JAK2 gene (JAK2-V617F) is frequently found in patients with myeloproliferative disorders (MPD). In most studies the JAK2-V617F mutation has been analyzed at single time point. Here we performed a retrospective single center study on 73 MPD patients (36 polycythemia vera (PV), 29 essential thrombocythemia (ET), and 8 primary myelofibrosis (PMF)) from whom at least two blood samples (mean=5, range 2–17) were available with an interval of at least 8 months. The mean follow-up period was 35±17 months (range 8–78 months). The allelic ratio of JAK2-V617F (%T) was determined in DNA from purified peripheral blood granulocytes by allele-specific PCR. In 73 MPD patients studied, 53 (73%) carried the JAK2-V617F mutation (32 PV, 18 ET, 3 PMF). None of the 20 patients negative for JAK2-V617F acquired the JAK2-V617F mutation during the observation period (n=20, mean number of samples=4). In the majority of the JAK2-V617F positive patients (35/53; 66%) the JAK2-V617F allelic ratios remained remarkably stable during the follow-up period (variation ±5%T) (Figure 1 A and B). In 10/53 patients (19%) we observed an increase and in 8/53 (15%) a decrease in JAK2-V617F allelic ratio greater than 5%T. Interestingly, 3/10 patients (1 ET and 2 PV) who showed increase of JAK2-V617F developed secondary myelofibrosis. Twenty six patients (49%) received cytoreductive treatment (hydroxyurea: 24, interferon alpha: 1, anagrelide: 1). Cytoreduction with hydroxyurea did not significantly reduce the JAK2-V617F allelic ratios (Figure 1A) compared to untreated patients (Figure 1B). The only molecular remission was seen in one patient treated with interferon alpha (Figure 1 A). In one patient without cytoreduction JAK2-V617F became undetectable because of transformation to acute myeloid leukemia with blast cells negative for JAK2-V617F. A second patient treated with hydroxyurea showed a pronounced decrease of JAK2-V617F (–47%T in 6 months), but no clinical or laboratory signs of leukemic transformation were present. We conclude that the amount of JAK2-V617F remains very stable in a majority of JAK2-V617F positive patients. Prospective studies will help to elucidate whether increasing JAK2-V617F allelic ratios can predict secondary myelofibrosis or decreasing allelic ratios in absence of cytoreductive therapy (e.g. interferon alpha) are early signs of leukemic transformation.
Figure 1A. Figure 1A. Figure 1B. Figure 1B.
Overexpression of JAK2 mRNA in Chronic Myeloproliferative Disease and Its Implication on Mutation Testing and Biology of Disease.
Authors: Ma Wanlong , Zhang Xi , Jilani Iman , Zhang Zhong , Kantarjian Hagop , Verstovsek Srdan , Giles Francis , O’Brien Susan , Albitar Maher 
Published: April 2020

Abstract
The V617F point mutation in the JAK2 gene is considered the most important molecular abnormality that characterizes patients with non-chronic myeloid leukemia (CML)-myeloproliferative disease (MPD). While it is well-documented that the V617F mutation leads to continuous activation of the JAK2-STAT5 pathway, the levels of JAK2 mRNA expression is not well defined in myeloproliferative diseases. We quantified the levels total JAK2 mRNA as well as V617F mutant mRNA in the plasma of patients with non-CML MPD using RT/PCR, and compared the results with clinical findings and disease behavior. Patients with non-CML MPD (n = 175) had significantly higher levels (P &lt;0.0001) of JAK2 mRNA (median, 1843 pg/ul) than patients with CML (median, 71.53 pg/ul) and normal controls (median, 34.34 pg/ul). In contrast, there was no significant difference (P = 0.15) in DNA levels (copies of JAK2 DNA/ul plasma) between CML patients and non-CML MPD patients. There was no significant difference in JAK2 mRNA levels in the MPD group between patients with or without the V617F mutation. There was no significant difference in JAK2 mRNA levels between patients with polycythemia vera, essential thrombocythemia, or agnogenic myeloid metaplasia, or unclassified MPD (P = 0.09). Survival data was available for only 68 patients; JAK2 mRNA levels in these patients did not correlate with overall survival. In contrast, mutant (V617F) JAK2 mRNA levels in the plasma correlated negatively with overall survival in continuous fashion (P = 0.04) when all patients (with and without the mutation) were considered, as well as when only patients with the mutation were considered (P = 0.03). In contrast, when we quantified levels of mutant JAK2 DNA, 4 of the 68 patients who showed mutation using RNA were negative for the V617F mutation by DNA analysis, and the levels of mutant JAK2 DNA did not correlate with survival. This data suggests that JAK2 mRNA is overexpressed in all patients with non-CML MPD, and levels of mutant JAK2 mRNA may correlate with clinical behavior. Furthermore, when testing for JAK2 mutation, RNA rather than DNA should be used.
Lenalidomide Oral Monotherapy Produces a 53% Response Rate in Patients with Relapsed/Refractory Mantle-Cell Non-Hodgkin’s Lymphoma.
Authors: Tuscano Joseph M. , Lossos Izidore S. , Justice Glen , Vose Julie M. , Takeshita Kenichi , Ervin-Haynes Annette , Pietronigro Dennis , Zeldis Jerome B. , Habermann Thomas M. 
Published: April 2020

Abstract
Background: Mantle cell lymphoma (MCL) is a distinct type of non-Hodgkin’s Lymphoma characterized by being incurable with a low response rate and short progression free survival when treated with conventional chemotherapy agents. Lenalidomide (Revlimid®), an immunomodulatory drug, is approved for the treatment of relapsed/refractory multiple myeloma and myelodysplastic syndromes associated with a del(q5) cytogenetic abnormality. Lenalidomide has also shown activity in chronic lymphocytic leukemia and cutaneous T-cell lymphoma.
Aim: To determine the activity and safety of lenalidomide in relapsed/refractory MCL.
Methods: Patients with relapsed/refractory MCL and measurable disease ≥ 2 cm after at least 1 prior treatment regimen were eligible. Patients received 25 mg lenalidomide orally once daily on Days 1–21 every 28 days and continued therapy for 52 weeks as tolerated or until disease progression. Response and progression were evaluated using the IWLRC methodology.
Results: Fifteen patients with MCL were enrolled. Median age was 67 (45–84) and 7 were female. Median time from diagnosis to lenalidomide was 5.1 (0.7–12.7) years and median number of prior treatment regimens was 4 (2–6). Eight patients (53%) exhibited an objective response (1 complete response (CR), 1 complete response unconfirmed (CRu) and 6 partial responses (PR)), 2 had stable disease (SD) and 5 had progressive disease (PD). All eight responses were in eleven patients having a tumor burden &lt; 50 cm2 and a time since last rituximab therapy of ≥ 230 days. No responses were achieved in four patients having a tumor burden ≥ 50 cm2 or a time since last rituximab therapy of &lt; 230 days. Four of 5 patients (80%) with a prior stem cell transplant responded. Progression free survival [PFS] is 5.7 months and ongoing. Seven patients (47%) required at least one dose reduction with a median time to first dose reduction of 2.3 months (1.2–4.9). Grade 4 adverse events were neutropenia (13%), thrombocytopenia (13%), and thromboembolism (13%). Most common Grade 3 adverse events were neutropenia (33%) and leukopenia (20%).
Conclusion: Lenalidomide oral monotherapy produced a 53% response rate in relapsed/refractory MCL with manageable side effects.
Functional Regulation of TEL through MOZ-Induced Acetylation.
Authors: Maki Kazuhiro , Nakamura Fumihiko , Yamagata Tetsuya , Kitabayashi Issay , Mitani Kinuko 
Published: April 2020

Abstract
TEL, a member of ETS transcription factors, acts as a transcriptional repressor and a tumor suppressor. TEL is inactivated by genomic alterations such as deletion and chromosomal translocation in a variety of human leukemia. TEL also has important roles in the maintenance of hematopoietic stem cells and differentiation of erythroid progenitors. Regulation of its function through phosphorylation and sumoylation has been described in the past literatures. We here demonstrated that TEL is also regulated by acetylation, another mode of post-translational modification. First, immunoprecipitation assay using anti-acetylated lysine (Ack) antibody showed that TEL proteins overexpressed in 293T cells were acetylated in vivo. To determine the acetylated lysine residue(s), we used a set of TEL mutants in which one of 16 lysine residues in the molecule was left with all the others substituted with arginine. We found that TEL was acetylated only at Lys99. To confirm that TEL is acetylated in hematopoietic cells, we established mouse erythroleukemia (MEL) cell clones expressing wild-type-TEL or K99R mutant in which Lys99 was substituted with arginine, and demonstrated acetylation of TEL at the same lysine residue in MEL cells by in vivo acetylation assay using [1–14C] acetic acid. Next, to identify histone acetyltransferase that is responsible for acetylation of TEL, we co-expressed each one of several known histone acetyltransferases such as p300, CBP, P/CAF and MOZ with TEL. The immunoprecipitation assay using anti-Ack antibody showed that only MOZ induced acetylation of TEL proteins among them. Physical interaction between TEL and MOZ was detected in immunoprecipitation assay. In order to get insights into functional modification of TEL through MOZ-induced acetylation, we examined whether the acetylation alters trans-repressional abilities of TEL. We employed pGL2-754TR reporter that has a natural promoter derived from stromelysin-1, one of TEL’s target genes, in luciferase assays. A two-fold decrease in luciferase activities was observed when TEL was expressed. Importantly, co-expression of MOZ attenuated the transcriptional suppression by TEL. Furthermore, to analyze alterations of TEL’s biological functions through acetylation, we employed MEL cells whose erythroid differentiation is accelerated by TEL, and compared the effect of overexpression between wild-type-TEL and its K99R mutant. Interestingly, K99R mutant stimulated erythroid differentiation with a more extent than wild-type-TEL. All these data suggest that molecular and biological functions of TEL might be controlled negatively through MOZ-induced acetylation at Lys99. Being a tumor suppressor, functional inactivation of TEL through protein modification mechanisms could be critical in the development and progression of human leukemia.
DMT1 Expression Is Regulated by DMT1 Associated Protein (DAP) in K562 Cells.
Authors: Okazaki Yasumasa , Yin Hong , Ma Yuxiang , Okazaki Emiko , Yeh Mary , Yeh Kwo-yih , Glass Jonathan 
Published: April 2020

Abstract
While iron is essential for cell growth and survival excess iron through oxidative stress may produce hepatitic cirrhosis and hepatocellular carcinoma, diabetes mellitus, and cardiomyopathy. Iron is absorbed across the duodenum with transport across the brush border mediated by DMT1 and across the basolateral surface by ferroportin with mechanisms that are inversely regulated by body iron concentrations. We have identified in rat intestine DAP, a novel protein that binds to the C-terminus of DMT1 (IRE) but not to the C-terminus of the non-IRE isoform (Blood, Nov 2004; 104: 53). DAP is a 526 amino acid protein that has been previously described as binding to the peripheral benzodiazepine receptor, an intrinsic mitochondrial protein involved in steriodogenesis and possibly in protoporphyrin IX transport into the mitochrondria. To investigate if DAP may have a role in regulation of intracellular iron transport DAP expression was down regulated using a vector containing a siRNA for DAP transfected into K562 cells by electroporation. Expression levels of DAP, transferrin receptor 1 (TfR1), divalent metal transporter 1 (DMT1) and ferritin were examined by western blot and quantitative quantitivative PCR assays from days 1 to 6 after transfection. Following transfection with the DAP siRNA DAP mRNA levels were decreased 50% by day 1 with DAP protein levels decreasing by 50% at day 3. The DAP siRNA also decreased DMT1 protein expression by about 50% for the DMT1 (IRE) protein but had no effect on the protein derived from the non-IRE isoform. The leels of DMT1 mRNA were not affected by DAP siRNA. The decrease of DAP expression was not associated with any change in TfR1 or ferritin expression, suggesting that altered levels of DAP did not affect intracellular iron pools. Transfection with the DAP siRNA resulted also in more protean effects decreasing cell proliferation, the transition from S-phase to G2 in cell cycle, and protein synthesis. These data are consistent with DAP regulating DMT1 expression in K562 cells by modulating turnover of DMT1 (IRE) protein and also having more global effects on cellular metabolism.