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1.
Artigo em Inglês | MEDLINE | ID: mdl-38117442

RESUMO

Improving understanding of behaviors that increase or reduce cancer risk for different Hispanic groups is a public health priority; such knowledge is sparse in new gateway immigration locations such as Indiana. The aims of this study were to: 1) describe cancer beliefs and cancer preventive/risk reduction behaviors (physical activity, tobacco, and alcohol use) among Hispanic adults; 2) examine differences in cancer beliefs and preventive behaviors by country/territory of birth, socioeconomic status, and area of residence (urban vs. rural); and 3) determine predictors of engagement in cancer prevention and risk reduction behaviors in this population. A cross-sectional online survey targeted adult Indiana residents who identified as Latino, Hispanic, or Spanish recruited using Facebook-targeted advertising. Complete survey data from 1520 respondents were analyzed using descriptive, unadjusted, and adjusted models. The majority of respondents believed they were unlikely to get cancer but held many other fatalistic beliefs about cancer. Only 35.6% of respondents had received the HPV vaccine, 37.6% reported they were currently smoking cigarettes, and 64% reported occasional or frequent drinking of alcohol. Respondents spent an average of 3.55 days per week engaged in moderate exercise. Differences were observed by country/territory of birth, income, and education but not by rural residence status. Predictors of cancer risk/risk reduction behaviors were identified. The Hispanic population in Indiana is diverse and effective interventions for cancer prevention should be culturally targeted based on country/territory of birth and individually tailored based on cancer-related beliefs.

2.
Int J Nurs Educ Scholarsh ; 20(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37470497

RESUMO

OBJECTIVES: This case study explored implementation of a Decision-Based Learning (DBL) tool for teaching arterial blood gas (ABG) analysis to nursing students. METHODS: For this mixed-methods study, ABG problems in a DBL model were solved by nursing students. Students answered a survey about their experience with DBL. Quantitative survey results are reported with descriptive statistics. Open-ended questions and instructor and student interview data were qualitatively analyzed. RESULTS: Students had a positive experience with DBL and gained self-efficacy regarding ABG analysis. The tool was engaging, simple to use, and not overly time-consuming. CONCLUSIONS: DBL can be a useful tool for teaching ABG analysis to nursing students. Implications for an international audience nursing students everywhere benefit from understanding ABG analysis. DBL is a promising tool that can be used in any location with digital resources.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Humanos , Bacharelado em Enfermagem/métodos , Inquéritos e Questionários , Autoeficácia , Ensino
3.
J Cell Physiol ; 238(7): 1492-1506, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37051890

RESUMO

Low oxygen bone marrow (BM) niches (~1%-4% low O2 ) provide critical signals for hematopoietic stem/progenitor cells (HSC/HSPCs). Our presented data are the first to investigate live, sorted HSC/HSPCs in their native low O2 conditions. Transcriptional and proteomic analysis uncovered differential Ca2+ regulation that correlated with overlapping phenotypic populations consisting of robust increases of cytosolic and mitochondrial Ca2+ , ABC transporter (ABCG2) expression and sodium/hydrogen exchanger (NHE1) expression in live, HSC/HSPCs remaining in constant low O2. We identified a novel Ca2+ high population in HSPCs predominantly detected in low O2 that displayed enhanced frequency of phenotypic LSK/LSKCD150 in low O2 replating assays compared to Ca2+ low populations. Inhibition of the Ca2+ regulator NHE1 (Cariporide) resulted in attenuation of both the low O2 induced Ca2+ high population and subsequent enhanced maintenance of phenotypic LSK and LSKCD150 during low O2 replating. These data reveal multiple levels of differential Ca2+ regulation in low O2 resulting in phenotypic, signaling, and functional consequences in HSC/HSPCs.


Assuntos
Cálcio , Células-Tronco Hematopoéticas , Oxigênio , Medula Óssea/química , Medula Óssea/metabolismo , Cálcio/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Oxigênio/metabolismo , Proteômica , Animais , Camundongos
4.
Cancer Med ; 12(6): 7470-7484, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36683200

RESUMO

BACKGROUND: Cancer is the leading cause of death for Hispanics in the USA. Screening and prevention reduce cancer morbidity and mortality. METHODS: This study administered a cross-sectional web-based survey to self-identified Hispanic residents in the state of Indiana to assess their cancer-related knowledge, beliefs, and behaviors, as well as to identify what factors might be associated with cancer screening and prevention. Chi-square and Fisher's exact test were used to compare associations and logistic regression used to develop both univariate and multivariate regression models. RESULTS: A total of 1520 surveys were completed, median age of respondents was 53, 52% identified as men, 50.9% completed the survey in Spanish, and 60.4% identified the USA as their country of birth. Most were not able to accurately identify ages to begin screening for breast, colorectal, or lung cancer, and there were significant differences in cancer knowledge by education level. US-born individuals with higher income and education more often believed they were likely to develop cancer and worry about getting cancer. Sixty eight percent of respondents were up-to-date with colorectal, 44% with breast, and 61% with cervical cancer screening. Multivariate models showed that higher education, lack of fatalism, older age, lower household income, and unmarried status were associated with cervical cancer screening adherence. CONCLUSIONS: Among a Hispanic population in the state of Indiana, factors associated with cervical cancer screening adherence were similar to the general population, with the exceptions of income and marital status. Younger Hispanic individuals were more likely to be adherent with breast and colorectal cancer screening, and given the higher incidence of cancer among older individuals, these results should guide future research and targeted outreach.


Assuntos
Neoplasias Colorretais , Neoplasias do Colo do Útero , Masculino , Feminino , Humanos , Indiana/epidemiologia , Neoplasias do Colo do Útero/diagnóstico , Detecção Precoce de Câncer , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Hispânico ou Latino , Programas de Rastreamento
5.
J Oncol Pharm Pract ; 29(2): 299-304, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34939868

RESUMO

Daratumumab is the first anti-CD38 targeting monoclonal antibody approved as monotherapy in multiply relapsed myeloma patients who progressed following prior treatment with proteasome inhibitors (PIs) and immunomodulatory agents (IMiDs). We present real world data on the efficacy of single agent daratumumab in a cohort of 55 multiply relapsed patients treated in the UK.The median age was 72 years, the majority (96%) received ≥ 3 previous lines of treatment; 54.5% were PI-refractory, 76.4% were IMiD-refractory and 47.2% were double refractory; 20% of patients had high-risk (HR) disease.The overall response rate was 49%. After a median follow up of 9.2 months, the median progression-free survival (PFS) for the total cohort was 5.1 months. Patients who achieved a partial response or better (≥PR) demonstrated a significantly longer PFS compared to those with

Assuntos
Mieloma Múltiplo , Humanos , Idoso , Mieloma Múltiplo/tratamento farmacológico , Agentes de Imunomodulação , Resultado do Tratamento , Anticorpos Monoclonais/efeitos adversos , Reino Unido , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
6.
PLoS One ; 17(7): e0270854, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35797277

RESUMO

The combination of panobinostat, bortezomib and dexamethasone (PanBorDex) is available as a treatment option for relapsed refractory multiple myeloma (RRMM) based on the PANORAMA-1 trial which investigated this triplet in early relapse. In routine clinical care, PanBorDex is used primarily in later relapses and is commonly administered in attenuated dosing schedules to mitigate the treatment-related toxicity. We set out to evaluate efficacy and safety outcomes with PanBorDex later in the disease course and evaluate the role of attenuated dosing schedules. This was a retrospective evaluation of patients treated in routine clinical practice between 2016-2019 across seven heamatology centres in the UK; patients who received at least one dose of PanBorDex were eligible for inclusion. The dosing schedule of panobinostat (10mg, 15mg or 20mg, twice or three times a week) and bortezomib (0.7mg/m2, 1mg/m2 or 1.3mg/m2 once or twice weekly) was as per treating physician choice. Patients received treatment until disease progression or unacceptable toxicity. The primary outcome is response rates according to IMWG criteria. Key secondary endpoints include progression-free survival (PFS) and overall survival (OS). Other secondary endpoints include rates of adverse events according to CTCAE criteria. In total, 61 patients were eligible for inclusion and received PanBorDex primarily as ≥5th line of treatment. One third of patients received PanBorDex at full dose, for the remaining two thirds, treatment was given in reduced dose intensities. The overall response rate was 44.2%, including 14.7% very good partial response (VGPR) rates; 68.8% of patients derived clinical benefit with stable disease or better. The median PFS was 3.4 months; non-refractory patients and those who achieved VGPR benefited from prolonged PFS of 11.4 months and 17.7 months, respectively. The median OS was 9.5 months. The triplet was associated with 45% and 18% incidence of grade 3-4 thrombocytopenia and diarrhea, respectively.


Assuntos
Bortezomib , Dexametasona , Mieloma Múltiplo , Panobinostat , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib/efeitos adversos , Bortezomib/uso terapêutico , Dexametasona/efeitos adversos , Dexametasona/uso terapêutico , Humanos , Mieloma Múltiplo/tratamento farmacológico , Panobinostat/efeitos adversos , Panobinostat/uso terapêutico , Estudos Retrospectivos , Reino Unido
7.
Br J Haematol ; 194(2): 365-377, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33959947

RESUMO

Mantle cell lymphoma (MCL) presenting in elderly, unfit patients represents a clinical challenge. Front-line 'attenuated' or low-intensity immunochemotherapy is often employed, although outcomes are relatively unexplored. We report outcomes of attenuated immunochemotherapy in 95 patients with MCL across 19 centres in the UK and Ireland considered unfit for full-dose rituximab-bendamustine or rituximab-cyclophosphamide, doxorubicin, vincristine, prednisolone (R-CHOP). Regimens examined were rituximab-cyclophosphamide, vincristine, prednisolone (R-CVP) (n = 19), dose-attenuated R-CHOP (n = 22), dose attenuated rituximab-bendamustine (n = 24) and rituximab-chlorambucil (n = 30). The primary outcome was progression-free survival (PFS). The secondary outcomes included overall response, overall survival (OS) and toxicity. The median (range) age was 79 (58-89) years and 50% were aged ≥80 years. The median (range) Cumulative Illness Rating Scale-Geriatric score was 6 (0-24). The median PFS for all patients was 15 months [95% confidence interval (CI) 8·7-21·2) and median OS was 31·4 months (95% CI 19·7-43·2). By multivariable analysis (MVA), the only clinical factor associated with an inferior PFS was blastoid morphology [hazard ratio (HR) 2·90, P = 0·01). Notably, higher treatment intensity (R-CHOP/R-bendamustine composite) provided an independently superior PFS compared with R-CVP/R-chlorambucil (MVA HR 0·49, P = 0·02). Factors associated with inferior OS by MVA were Eastern Cooperative Oncology Group Performance Status (HR 2·14, P = 0·04), blastoid morphology (HR 4·08, P = 0·001) and progression of disease at <24 months status (HR 5·68, P < 0·001). Overall, survival after front-line dose-attenuated immunochemotherapy is unsatisfactory. Clinical trials investigating novel agents such as Bruton tyrosine kinase and B-cell lymphoma 2 inhibitors in this specific clinical setting are warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/uso terapêutico , Linfoma de Célula do Manto/tratamento farmacológico , Prednisona/uso terapêutico , Rituximab/uso terapêutico , Vincristina/uso terapêutico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doxorrubicina/uso terapêutico , Feminino , Humanos , Imunoterapia , Irlanda/epidemiologia , Linfoma de Célula do Manto/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Reino Unido/epidemiologia
9.
Epilepsy Res ; 161: 106283, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32062370

RESUMO

Seizures that occur during early development are associated with adverse neurodevelopmental outcomes. Causation and mechanisms are currently under investigation. Induction of an early life seizure by kainic acid (KA) in immature rats on post-natal day (P) 7 results in behavioral changes in the adult rat that reflect social and intellectual deficits without overt cellular damage. Our previous work also demonstrated increased expression of CA1 hippocampal long-term potentiation (LTP) and reduced desensitization of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type ionotropic glutamate receptors (AMPA-R) one week following a kainic acid induced seizure (KA-ELS). Here we used RNA sequencing (RNAseq) of mRNA from dorsal hippocampal CA1 to probe changes in mRNA levels one week following KA-ELS as a means to investigate the mechanisms for these functional changes. Ingenuity pathway analysis (IPA) confirmed our previous results by predicting an up-regulation of the synaptic LTP pathway. Differential gene expression results revealed significant differences in 7 gene isoforms. Additional assessments included AMPA-R splice variants and adenosine deaminase acting on RNA 2 (ADAR2) editing sites as a means to determine the mechanism for reduced AMPA-R desensitization. Splice variant analysis demonstrated that KA-ELS result in a small, but significant decrease in the "flop" isoform of Gria3, and editing site analysis revealed significant changes in the editing of a kainate receptor subunit, Grik2, and a serotonin receptor, Htr2c. While these specific changes may not account for altered AMPA-R desensitization, the differences indicate that KA-ELS alters gene expression in the hippocampal CA1 one week after the insult.


Assuntos
Perfilação da Expressão Gênica , Hipocampo/efeitos dos fármacos , Convulsões/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia , Animais , Hipocampo/metabolismo , Ácido Caínico/farmacologia , Neurônios/efeitos dos fármacos , Ratos Sprague-Dawley , Receptores de AMPA/metabolismo , Convulsões/diagnóstico , Convulsões/fisiopatologia , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/metabolismo
11.
Exp Hematol ; 54: 1-3, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28668351

RESUMO

Since the end of the 20th century, novel approaches have emerged to manipulate experimental models of hematological disorders so that they more accurately mirror what is observed in the clinical setting. Despite these technological advances, the characterization of crucial genes for benign or malignant hematological disorders remains challenging, given the dynamic nature of the hematopoietic system and the genetic heterogeneity of these disorders. To overcome this limitation, genome-editing technologies have been developed to manipulate the genome specifically via deletion, insertion, or modification of targeted loci. These technologies have progressed swiftly, allowing their common use to investigate genetic function in experimental hematology. Among them, homologous-recombination-mediated targeting technologies have facilitated the manipulation of specific loci by generating knock-out and knock-in models. Despite promoting significant advances in our understanding of the molecular mechanisms involved in hematology, these inefficient, time-consuming, and labor-intensive approaches did not permit the development of cellular or animal models, recapitulating the complexity of hematological disorders. On October 26, 2016, Drs. Ben Ebert and Chad Cowan shared their knowledge of and experience with the utilization of CRISPR for models of myeloid malignancy, disease, and novel therapeutics in an International Society for Experimental Hematology webinar titled "Utility of CRISPR/Cas9 Systems in Hematology Research." Here, we provide an overview of the topics they covered, including their insights into the novel applications of the technique and its strengths and limitations.


Assuntos
Sistemas CRISPR-Cas , Deleção de Genes , Edição de Genes/métodos , Genoma , Neoplasias Hematológicas/genética , Mutagênese Insercional , Animais , Modelos Animais de Doenças , Genes Reporter , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patologia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos
12.
Oncotarget ; 8(66): 110350-110357, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29299152

RESUMO

Delayed engraftment remains a limitation of umbilical cord blood (UCB) transplantation. We previously showed that inhibition of dipeptidylpeptidase (DPP)-4 using sitagliptin 600 mg daily was safe with encouraging results on engraftment, but inhibition was not sustained. We evaluated the efficacy and feasibility of higher doses of sitagliptin to enhance engraftment of UCB in patients with hematological cancers. Fifteen patients, median age 41 (range, 18-59) years, received single UCB grafts matched at 4 (n=11) or 5 (n=4) of 6 HLA loci with median nucleated cell dose of 3.5 (range, 2.57-4.57) x107/kg. Sitagliptin 600 mg every 12 hours was administered days -1 to +2. All patients engrafted by day 30, with 12 (80%) engrafting by day 21. The median time to neutrophil engraftment was 19 (range, 12-30) days. Plasma DPP-4 activity was better inhibited with a mean residual trough DPP-4 activity of 70%±19%. Compared to patients previously treated with 600 mg/day, sitagliptin 600 mg every 12 hours appeared to improve engraftment, supporting the hypothesis that more sustained DPP-4 inhibition is required. In-vivo inhibition of DPP-4 using high-dose sitagliptin compares favorably with other approaches to enhance UCB engraftment with greater simplicity, and may show synergy in combination with other strategies.

13.
Cell ; 161(7): 1553-65, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26073944

RESUMO

Hematopoietic stem cells (HSCs) reside in hypoxic niches within bone marrow and cord blood. Yet, essentially all HSC studies have been performed with cells isolated and processed in non-physiologic ambient air. By collecting and manipulating bone marrow and cord blood in native conditions of hypoxia, we demonstrate that brief exposure to ambient oxygen decreases recovery of long-term repopulating HSCs and increases progenitor cells, a phenomenon we term extraphysiologic oxygen shock/stress (EPHOSS). Thus, true numbers of HSCs in the bone marrow and cord blood are routinely underestimated. We linked ROS production and induction of the mitochondrial permeability transition pore (MPTP) via cyclophilin D and p53 as mechanisms of EPHOSS. The MPTP inhibitor cyclosporin A protects mouse bone marrow and human cord blood HSCs from EPHOSS during collection in air, resulting in increased recovery of transplantable HSCs. Mitigating EPHOSS during cell collection and processing by pharmacological means may be clinically advantageous for transplantation.


Assuntos
Medula Óssea , Sangue Fetal/citologia , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Peptidil-Prolil Isomerase F , Ciclofilinas/metabolismo , Feminino , Transplante de Células-Tronco Hematopoéticas/instrumentação , Células-Tronco Hematopoéticas/citologia , Humanos , Hipóxia , Camundongos , Camundongos Endogâmicos C57BL , Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo
14.
Curr Opin Hematol ; 22(4): 273-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26049746

RESUMO

PURPOSE OF REVIEW: Hematopoietic stem (HSCs) and progenitor (HPCs) cells reside in a hypoxic (lowered oxygen tension) environment, in vivo. We review literature on growth of HSCs and HPCs under hypoxic and normoxic (ambient air) conditions with a focus on our recent work demonstrating the detrimental effects of collecting and processing cells in ambient air through a phenomenon termed extra physiologic oxygen shock/stress (EPHOSS), and we describe means to counteract EPHOSS for enhanced collection of HSCs. RECENT FINDINGS: Collection and processing of bone marrow and cord blood cells in ambient air cause rapid differentiation and loss of HSCs, with increases in HPCs. This apparently irreversible EPHOSS phenomenon results from increased mitochondrial reactive oxygen species, mediated by a p53-cyclophilin D-mitochondrial permeability transition pore axis, and involves hypoxia inducing factor-1α and micro-RNA 210. EPHOSS can be mitigated by collecting and processing cells in lowered (3%) oxygen, or in ambient air in the presence of, cyclosporine A which effects the mitochondrial permeability transition pore, resulting in increased HSC collections. SUMMARY: Our recent findings may be advantageous for HSC collection for hematopoietic cell transplantation, and likely for enhanced collection of other stem cell types. EPHOSS should be considered when ex-vivo cell analysis is utilized for personalized medicine, as metabolism of cells and their response to targeted drug treatment ex vivo may not mimic what occurs in vivo.


Assuntos
Coleta de Amostras Sanguíneas/métodos , Células da Medula Óssea/metabolismo , Sangue Fetal/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Hipóxia/metabolismo , Células da Medula Óssea/citologia , Diferenciação Celular , Ciclofilinas/genética , Ciclofilinas/metabolismo , Sangue Fetal/citologia , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Humanos , Hipóxia/genética , Hipóxia/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Stem Cells ; 31(8): 1447-53, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23733396

RESUMO

Understanding the factors that regulate hematopoiesis opens up the possibility of modifying these factors and their actions for clinical benefit. DEK, a non-histone nuclear phosphoprotein initially identified as a putative proto-oncogene, has recently been linked to regulate hematopoiesis. DEK has myelosuppressive activity in vitro on proliferation of human and mouse hematopoietic progenitor cells and enhancing activity on engraftment of long-term marrow repopulating mouse stem cells, has been linked in coordinate regulation with the transcription factor C/EBPα, for differentiation of myeloid cells, and apparently targets a long-term repopulating hematopoietic stem cell for leukemic transformation. This review covers the uniqueness of DEK, what is known about how it now functions as a nuclear protein and also as a secreted molecule that can act in paracrine fashion, and how it may be regulated in part by dipeptidylpeptidase 4, an enzyme known to truncate and modify a number of proteins involved in activities on hematopoietic cells. Examples are provided of possible future areas of investigation needed to better understand how DEK may be regulated and function as a regulator of hematopoiesis, information possibly translatable to other normal and diseased immature cell systems.


Assuntos
Proteínas Cromossômicas não Histona/fisiologia , Proteínas de Ligação a DNA/fisiologia , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Proteínas Oncogênicas/fisiologia , Animais , Humanos , Proteínas de Ligação a Poli-ADP-Ribose , Proto-Oncogene Mas
16.
Blood ; 122(2): 161-9, 2013 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-23637126

RESUMO

Dipeptidylpeptidase (DPP) 4 has the potential to truncate proteins with a penultimate alanine, proline, or other selective amino acids at the N-terminus. DPP4 truncation of certain chemokines, colony-stimulating factors, and interleukins have recently been linked to regulation of hematopoietic stem/progenitor cells, more mature blood cells, and other cell types. We believe that the potential role of DPP4 in modification of many regulatory proteins, and their subsequent effects on numerous stem/progenitor and other cell-type functions has not been adequately appreciated. This review addresses the potential implications of the modifying effects of DPP4 on a large number of cytokines and other growth-regulating factors with either proven or putative DPP4 truncation sites on hematopoietic cells, and subsequent effects of DPP4-truncated proteins on multiple aspects of steady-state and stressed hematopoiesis, including stem/progenitor cell, and more mature cell, function.


Assuntos
Dipeptidil Peptidase 4/metabolismo , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Proteínas/metabolismo , Animais , Diferenciação Celular , Linhagem da Célula , Movimento Celular/fisiologia , Células-Tronco Embrionárias/metabolismo , Células-Tronco Hematopoéticas/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Células Progenitoras Linfoides/metabolismo , Modelos Biológicos , Células Progenitoras Mieloides/metabolismo
17.
Curr Opin Hematol ; 20(4): 314-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23594692

RESUMO

PURPOSE OF REVIEW: Dipeptidyl peptidase 4 (DPP4, CD26) is a protease that cleaves selected amino acids at the N-terminal penultimate position and has the potential to alter the protein function. The regulation and roles of DPP4 activity are not well understood; therefore, the purpose of this review is to discuss the recent literature regarding DPP4 regulation, as well as the variety of molecules it may affect, and their potential clinical applications. RECENT FINDINGS: Recent insight into the number of proteins that have DPP4 sites, and how DPP4 truncation may alter hematopoiesis based on the protein full length vs. truncated state, has shown that DPP4 truncation of colony-stimulating factors (CSFs) alters their function and that the activity of these CSFs can be enhanced when DPP4 activity is inhibited. DPP4 inhibition has recently been used in a clinical trial to attempt to enhance the engraftment of cord blood cells, and an endogenous DPP4 inhibitor tissue factor pathway inhibitor has been discovered, increasing our understanding of the potential importance of DPP4. SUMMARY: DPP4 plays a role in regulating the activity of CSFs and other cytokines involved in hematopoiesis. This information may be useful for enhancing hematopoietic cell transplantation, blood cell recovery after stress, and for understanding the physiology and pathophysiology of blood and other cell systems.


Assuntos
Dipeptidil Peptidase 4/fisiologia , Hematopoese/fisiologia , Transplante de Células-Tronco Hematopoéticas , Fatores Estimuladores de Colônias/metabolismo , Inibidores da Dipeptidil Peptidase IV , Humanos
18.
Nat Med ; 18(12): 1786-96, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23160239

RESUMO

Enhancement of hematopoietic recovery after radiation, chemotherapy, or hematopoietic stem cell (HSC) transplantation is clinically relevant. Dipeptidylpeptidase (DPP4) cleaves a wide variety of substrates, including the chemokine stromal cell-derived factor-1 (SDF-1). In the course of experiments showing that inhibition of DPP4 enhances SDF-1-mediated progenitor cell survival, ex vivo cytokine expansion and replating frequency, we unexpectedly found that DPP4 has a more general role in regulating colony-stimulating factor (CSF) activity. DPP4 cleaved within the N-termini of the CSFs granulocyte-macrophage (GM)-CSF, G-CSF, interleukin-3 (IL-3) and erythropoietin and decreased their activity. Dpp4 knockout or DPP4 inhibition enhanced CSF activities both in vitro and in vivo. The reduced activity of DPP4-truncated versus full-length human GM-CSF was mechanistically linked to effects on receptor-binding affinity, induction of GM-CSF receptor oligomerization and signaling capacity. Hematopoiesis in mice after radiation or chemotherapy was enhanced in Dpp4(-/-) mice or mice receiving an orally active DPP4 inhibitor. DPP4 inhibition enhanced engraftment in mice without compromising HSC function, suggesting the potential clinical utility of this approach.


Assuntos
Quimiocina CXCL12/metabolismo , Dipeptidil Peptidase 4/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Hematopoese/fisiologia , Radioterapia/efeitos adversos , Transdução de Sinais/fisiologia , Animais , Linhagem Celular , Primers do DNA/genética , Dipeptidil Peptidase 4/genética , Hematopoese/efeitos dos fármacos , Hematopoese/efeitos da radiação , Humanos , Imunofenotipagem , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/genética
19.
PLoS One ; 7(2): e30758, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363485

RESUMO

Hematopoietic reconstitution, following bone marrow or stem cell transplantation, requires a microenvironment niche capable of supporting both immature progenitors and stem cells with the capacity to differentiate and expand. Osteoblasts comprise one important component of this niche. We determined that treatment of human primary osteoblasts (HOB) with melphalan or VP-16 resulted in increased phospho-Smad2, consistent with increased TGF-ß1 activity. This increase was coincident with reduced HOB capacity to support immature B lineage cell chemotaxis and adherence. The supportive deficit was not limited to committed progenitor cells, as human embryonic stem cells (hESC) or human CD34+ bone marrow cells co-cultured with HOB pre-exposed to melphalan, VP-16 or rTGF-ß1 had profiles distinct from the same populations co-cultured with untreated HOB. Functional support deficits were downstream of changes in HOB gene expression profiles following chemotherapy exposure. Melphalan and VP-16 induced damage of HOB suggests vulnerability of this critical niche to therapeutic agents frequently utilized in pre-transplant regimens and suggests that dose escalated chemotherapy may contribute to post-transplantation hematopoietic deficits by damaging structural components of this supportive niche.


Assuntos
Antineoplásicos/efeitos adversos , Células da Medula Óssea/patologia , Osteoblastos/patologia , Animais , Antígenos CD34/metabolismo , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Adesão Celular/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Linhagem Celular , Quimiocina CXCL12/metabolismo , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Melfalan/efeitos adversos , Camundongos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta1/farmacologia
20.
J Biol Chem ; 286(36): 31272-81, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-21768120

RESUMO

The Ca(2+)/calmodulin (CaM)-dependent protein kinase II (CaMKII) and the NMDA-type glutamate receptor are key regulators of synaptic plasticity underlying learning and memory. Direct binding of CaMKII to the NMDA receptor subunit GluN2B (formerly known as NR2B) (i) is induced by Ca(2+)/CaM but outlasts this initial Ca(2+)-stimulus, (ii) mediates CaMKII translocation to synapses, and (iii) regulates synaptic strength. CaMKII binds to GluN2B around S1303, the major CaMKII phosphorylation site on GluN2B. We show here that a phospho-mimetic S1303D mutation inhibited CaM-induced CaMKII binding to GluN2B in vitro, presenting a conundrum how binding can occur within cells, where high ATP concentration should promote S1303 phosphorylation. Surprisingly, addition of ATP actually enhanced the binding. Mutational analysis revealed that this positive net effect was caused by four modulatory effects of ATP, two positive (direct nucleotide binding and CaMKII T286 autophosphorylation) and two negative (GluN2B S1303 phosphorylation and CaMKII T305/6 autophosphorylation). Imaging showed positive regulation by nucleotide binding also within transfected HEK cells and neurons. In fact, nucleotide binding was a requirement for efficient CaMKII interaction with GluN2B in cells, while T286 autophosphorylation was not. Kinetic considerations support a model in which positive regulation by nucleotide binding and T286 autophosphorylation occurs faster than negative modulation by GluN2B S1303 and CaMKII T305/6 phosphorylation, allowing efficient CaMKII binding to GluN2B despite the inhibitory effects of the two slower reactions.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Nucleotídeos/farmacologia , Receptores de N-Metil-D-Aspartato/metabolismo , Trifosfato de Adenosina/metabolismo , Sítios de Ligação , Linhagem Celular , Humanos , Cinética , Fosforilação , Ligação Proteica , Subunidades Proteicas
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