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1.
Cytotherapy ; 24(4): 437-443, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35086777

RESUMO

BACKGROUND: The COVID-19 pandemic has forced a fundamental change in the global procurement of allogeneic hematopoietic progenitor cells (HPCs) for transplantation. To better meet the emergent challenges of transporting cryopreserved allogeneic HPC during pandemics, there is an urgent need for External Quality Assurance (EQA) programs to evaluate reproducibility and harmonization of viable CD34+ cell (vCD34+) HPC enumeration, as the current EQA programs are unsuitable for analysis of vCD34+. The cost-effective distribution of HPC cryopreserved reference samples (CRSs) with acceptable reproducibility and specificity is key to the success of a vCD34+ EQA program. METHODS: Cryopreserved HPC samples (n = 11) were either stored on dry ice for 1 to 4 days or for 1 day followed by liquid nitrogen (LN) storage for 1 to 3 days to assess optimal conditions for vCD34+ EQA. Flow cytometric enumeration of vCD34+ HPCs was performed using a single platform assay combined with 7-AAD viability dye exclusion. The optimum transportation condition was validated in pilot and multicenter national studies (n = 12). RESULTS: A combination of 1 day on dry ice followed by LN storage stabilized viability compared with continuous storage on dry ice. This study demonstrates that dispatch of CRSs on dry ice to recipient centers across a distance of ≤4000 km within 26 h, followed by LN storage, resulted in reproducible intercenter vCD34+ enumeration. The estimated cost of safer and more convenient dry ice delivery is >20-fold lower than that of LN. CONCLUSION: This approach can form the basis for economically and scientifically acceptable distribution of CRSs for external vCD34+ EQA.


Assuntos
COVID-19 , Pandemias , Antígenos CD34 , COVID-19/epidemiologia , Criopreservação/métodos , Células-Tronco Hematopoéticas , Humanos , Pandemias/prevenção & controle , Reprodutibilidade dos Testes
2.
Intern Med J ; 52(1): 57-62, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33131163

RESUMO

BACKGROUND: Results have been varied regarding the effect of donor age on the outcome of unrelated donor haemopoietic cell transplantation (HCT). AIMS: To determine the influence of donor age on adult unrelated donor HCT outcome in Australia. METHODS: Patients were included in the study if they were aged 16 years or above and underwent first allogeneic unrelated donor HCT in Australia for the indications of acute lymphoblastic leukaemia (ALL), acute myelogenous leukaemia (AML), chronic myelogenous leukaemia (CML) or myelodysplastic syndromes (MDS) between the years of 2001 and 2014 inclusive. The main outcome measure was overall survival (OS), which was tested against independent variables using univariate Kaplan-Meier methods and multivariate Cox regression. RESULTS: A total of 1158 unrelated donor HCT were represented in the data. Cumulative incidences of engraftment, transplant related mortality (TRM), acute graft-versus-host disease (GvHD), chronic GvHD and relapse were not significantly affected by donor age. OS probability at 5 years post-transplant was 48.3%. In multivariate analysis of OS, year of transplant 2001-2007, recipient age 40 years or greater, poor risk disease, human leukocyte antigen (HLA) match less than 6/6 and poor performance status at transplant (Karnofsky scale) were independently significant adverse OS risk factors. Donor age was not a significant risk factor for OS in univariate or multivariate analysis. CONCLUSIONS: The conclusion from this study was that donor age (up to 59 years) did not influence post-transplant outcome among adult unrelated donor HCT performed in Australia for haematologic malignancies.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Doadores não Relacionados , Adolescente , Adulto , Austrália/epidemiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Recidiva Local de Neoplasia , Resultado do Tratamento
3.
J Neurol Neurosurg Psychiatry ; 90(5): 514-521, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30538138

RESUMO

BACKGROUND: Autologous haematopoietic stem cell transplantation (AHSCT) has been explored as a therapeutic intervention in multiple sclerosis (MS) over the last two decades; however, prospective clinical trials of the most common myeloablative conditioning regimen, BEAM, are limited. Furthermore, patient selection, optimal chemotherapeutic regimen and immunological changes associated with disease response require ongoing exploration. We present the outcomes, safety and immune reconstitution (IR) of patients with active, treatment refractory MS. METHODS: This study was a single-centre, phase II clinical trial of AHSCT for patients with active relapsing remitting (RRMS) and secondary progressive MS (SPMS). Patients underwent AHSCT using BEAM (carmustine, etoposide, cytarabine, melphalan)+antithymocyte globulin chemotherapeutic regimen. OUTCOMES: The primary outcome was event-free survival (EFS); defined as no clinical or radiological relapses and no disability progression. Multiparameter flow cytometry was performed for evaluation of post-transplant IR in both MS and lymphoma patients receiving the same chemotherapy regimen. RESULTS: Thirty-five patients (20 RRMS, 15 SPMS) completed AHSCT, with a median follow-up of 36 months (range 12-66). The median Expanded Disability Status Scores (EDSS) was 6 (2-7) and patients had failed a median of 4 (2-7) disease modifying therapies. 66% failed treatment with natalizumab. EFS at 3 years was 60%, (70% RRMS). Sustained improvement in EDSS was seen in 15 (44%) of patients. There was no treatment-related mortality. A sustained rise in CD39+ T regulatory cells, immunosuppressive CD56hi natural killer cells and ablation of proinflammatory mucosal-associated invariant T cells was seen for 12 months following AHSCT in patients with MS. These changes did not occur in patients with lymphoma receiving the same chemotherapy for AHSCT. CONCLUSIONS: The EFS in our MS cohort is significantly greater than other high-efficacy immunosuppressive therapies and similar to other AHSCT studies despite a more heavily pretreated cohort. TRIAL REGISTRATION NUMBER: ACTRN12613000339752.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Esclerose Múltipla Crônica Progressiva/terapia , Esclerose Múltipla Recidivante-Remitente/terapia , Adulto , Soro Antilinfocitário/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carmustina/uso terapêutico , Citarabina/uso terapêutico , Etoposídeo/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Prospectivos , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
4.
Biol Blood Marrow Transplant ; 24(1): 169-174, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28963078

RESUMO

We conducted a study to analyze and report on indicators of hematopoietic cell transplant (HCT) physician time use and HCT center output measures. HCT centers in Australia and New Zealand (A&NZ) were invited to provide demographic and time use details for physicians participating in HCT patient care (HCT physicians). Resource details for adult and pediatric centers were included. From a total of 46 centers that were invited to participate, completed data were received from 37 centers (80%) representing 185 HCT physicians, with a median age of 48 (range, 33 to 72), of whom 31% were women. Just over half of HCT physicians cited prior work experience in large overseas HCT centers (97, 52%) and over one-third (79, 43%) possessed postgraduate qualifications other than specialist training. Total annual mean HCTs per HCT physician full-time equivalent (FTE) were 14.2 for centers performing both allogeneic and autologous HCT, 6.6 for autologous only centers, and 10.6 for all centers. For all HCT physicians surveyed the mean proportion of time spent on HCT related tasks was 31.7%. In A&NZ, for centers that perform both allografts and autografts, there was a mean of 4.0 allogeneic HCT annually per HCT bed, compared with 2.6 for the United States and 7.1 allogeneic HCT annually per HCT physician FTE (United States, 6.3). Projections of the A&NZ HCT physician workforce indicated that the numbers of HCT physicians are likely to stay within the region of 170 to 190 for the next 10 years, whereas HCT activity will likely continue to climb steadily. Healthcare and government authorities should be prepared to enable and support greater HCT activity in A&NZ in the future.


Assuntos
Mão de Obra em Saúde/estatística & dados numéricos , Médicos/tendências , Adulto , Idoso , Austrália , Feminino , Transplante de Células-Tronco Hematopoéticas/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Médicos/organização & administração , Médicos/estatística & dados numéricos , Atenção Terciária à Saúde/estatística & dados numéricos
5.
Intern Med J ; 48(1): 16-24, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29068529

RESUMO

Escalating cost of medicines is rapidly becoming a serious threat to patients and health systems. This trend has been documented to impact patient outcomes adversely. As clinicians and tax payers, it is our responsibility to be aware of the potential detrimental effects spiralling costs have on our patients, our community and our health system and to mitigate these effects by exposing this issue to our respective professional societies, representatives of the pharmaceutical companies that we interact with, government regulatory bodies and to patients who we are caring for. Only through understanding and constructive actions will we be able to provide the best quality of care to our patients and continue to enjoy universal healthcare in our country.


Assuntos
Atenção à Saúde/economia , Atenção à Saúde/tendências , Custos de Medicamentos/tendências , Indústria Farmacêutica/educação , Indústria Farmacêutica/tendências , Austrália/epidemiologia , Humanos
6.
Biol Blood Marrow Transplant ; 22(2): 284-291, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26385524

RESUMO

This report describes hematopoietic cell transplantation (HCT) activity and outcome in Australia and New Zealand during the years 2005 to 2013. In 2013, 1018 autologous, 221 allogeneic with related donors, and 264 allogeneic with unrelated donors HCT were performed in 40 centers in Australia, with corresponding figures of 147, 39, and 47 in 6 centers in New Zealand. Annual numbers of HCT in 2013 increased, compared to 2005, by 25% in Australia and by 52% in New Zealand. The majority of both allogeneic and autologous HCT used peripheral blood as the stem cell source for all years studied. Major indications for transplantation were acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), plasma cell disorders, and non-Hodgkin lymphoma (NHL). Overall survival probabilities at 5 years after transplantation for adult (16+) allogeneic first HCT recipients were 54.2% for ALL, 46.0% for AML, 48.4% for myelodysplastic syndromes, and 58.6% for NHL. Consistent patterns over time include a steady increase in HCT, particularly for older recipients, relatively constant numbers of allografts using cord blood, and a recent increase in the number of allografts with 2 or more HLA-mismatched related donors.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Idoso , Austrália , Criança , Pré-Escolar , Transplante de Células-Tronco Hematopoéticas/mortalidade , História do Século XXI , Humanos , Lactente , Pessoa de Meia-Idade , Nova Zelândia , Condicionamento Pré-Transplante/mortalidade , Adulto Jovem
7.
Mol Cancer ; 13: 79, 2014 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-24708856

RESUMO

BACKGROUND: Acute myeloid leukaemia (AML) is characterised by the halt in maturation of myeloid progenitor cells, combined with uncontrolled proliferation and abnormal survival, leading to the accumulation of immature blasts. In many subtypes of AML the underlying causative genetic insults are not fully described. MicroRNAs are known to be dysregulated during oncogenesis. Overexpression of miR-155 is associated with some cancers, including haematological malignancies, and it has been postulated that miR-155 has an oncogenic role. This study investigated the effects of modulating miR-155 expression in human AML cells, and its mechanism of action. RESULTS: Analysis of miR-155 expression patterns in AML patients found that Fms-like tyrosine kinase 3 (FLT3)-wildtype AML has the same expression level as normal bone marrow, with increased expression restricted to AML with the FLT3-ITD mutation. Induction of apoptosis by cytarabine arabinoside or myelomonocytic differentiation by 1,23-dihydroxyvitaminD3 in FLT3-wildtype AML cells led to upregulated miR-155 expression. Knockdown of miR-155 by locked nucleic acid antisense oligonucleotides in the FLT3-wildtype AML cells conferred resistance to cytarabine arabinoside induced apoptosis and suppressed the ability of cells to differentiate.Ectopic expression of miR-155 in FLT3-wildtype AML cells led to a significant gain of myelomonocytic markers (CD11b, CD14 and CD15), increase in apoptosis (AnnexinV binding), decrease in cell growth and clonogenic capacity.In silico target prediction identified a number of putative miR-155 target genes, and the expression changes of key transcription regulators of myeloid differentiation and apoptosis (MEIS1, GF1, cMYC, JARID2, cJUN, FOS, CTNNB1 and TRIB2) were confirmed by PCR. Assessment of expression of apoptosis-related proteins demonstrated a marked increase in cleaved caspase-3 expression confirming activation of the apoptosis cascade. CONCLUSIONS: This study provides evidence for an anti-leukaemic role for miR-155 in human FLT3-wildtype AML, by inducing cell apoptosis and myelomonocytic differentiation, which is in contrast to its previously hypothesized role as an oncogene. This highlights the complexity of gene regulation by microRNAs that may have tumour repressor or oncogenic effects depending on disease context or tissue type.


Assuntos
Epigênese Genética , Leucemia Mieloide Aguda/genética , MicroRNAs/genética , Proteínas de Neoplasias/genética , Tirosina Quinase 3 Semelhante a fms/genética , Antígenos CD/genética , Antígenos CD/metabolismo , Antimetabólitos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citarabina/farmacologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HL-60 , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , MicroRNAs/metabolismo , Mutação , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Análise de Sobrevida , Células Tumorais Cultivadas , Tirosina Quinase 3 Semelhante a fms/metabolismo
8.
Cytotherapy ; 15(2): 224-30, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23321333

RESUMO

BACKGROUND AIMS: Expansion of hemopoietic stem cells (HSCs) in vitro is a potential strategy for improving transplant outcomes, but expansion methods tend to promote differentiation and loss of stem cell potential. Aryl hydrocarbon receptor antagonists (AhRAs) have recently been shown to protect HSC stemness during expansion; however, little is known of the T-cell regenerative capacity of AhRA-expanded HSCs. In this study, we confirm the protective effect of two commercially available AhRA compounds on HSCs from both cord blood (CB) and adult samples and assess the T-lymphocyte potential of the expanded cells. METHODS: Adult mobilized peripheral blood and CB samples were purified to CD34(+) cells, which were expanded in vitro with cytokines and AhRAs. After 14 d, CD34(+) cells were re-isolated and then grown on in OP9Delta co-culture under conditions that allow T-lymphocyte differentiation. Cells were monitored weekly for T-lineage markers by flow cytometry. RESULTS: Both AhRA compounds promoted maintenance of CD34 expression during 2 weeks of proliferation with growth factors, although adult cells proliferated markedly less than CB cells. AhRA-expanded CD34(+) cells from CB differentiated to T cells on OP9Delta co-culture with the same rate and time course as untreated cells. Adult cells, by contrast, had reduced differentiation to T cells, with donor-dependent variable responses. CONCLUSIONS: This study shows that whereas AhRA treatment is effective in CB samples, expansion of adult HSCs is less successful and reflects their inherent poor potential in T-cell generation.


Assuntos
Compostos Azo/administração & dosagem , Diferenciação Celular , Sangue Fetal/efeitos dos fármacos , Transplante de Células-Tronco Hematopoéticas , Pirazóis/administração & dosagem , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Antígenos CD34/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Sangue Fetal/citologia , Citometria de Fluxo , Humanos , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos
9.
Biol Blood Marrow Transplant ; 18(2): 302-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21620988

RESUMO

This retrospective registry analysis examined predictive factors for outcome in 57 patients who underwent allogeneic or syngeneic hematopoietic cell transplantation (HCT) for chronic myelofibrosis (CM), either primary (n = 49) or following an antecedent condition (n = 8), reported to the Australasian Bone Marrow Transplant Registry (ABMTRR) between 1993 and 2005. During the 6 years 2000 to 2005, 40 HCTs were performed for CM compared with 17 in the 7 years 1993 to 1999. Twenty-four recipients (42%) were age 50 or over at transplantation; all of these patients were transplanted after 1997, and 15 were given reduced intensity conditioning (RIC) pretransplantation. The cumulative incidence of transplantation-related mortality was 18% at 100 days and 25% at 1 year posttransplantation. Up to 1 year posttransplantation 16 patients died, with the most common causes being infection (n = 6) and graft-versus-host disease (GVHD) (n = 5). A total of 27 patients survived for 3 years or longer posttransplantation. None of these patients required regular red blood cell transfusions, and of the 17 who had not had splenectomies, none had detectable splenomegaly. Twelve patients had no detectable bone marrow fibrosis, 7 had grade 1 fibrosis, and in 8 patients no information was available. The overall survival (OS) probability for all patients was 72% at 1 year and 58% at 5 years posttransplantation. Patients age 50 and over who received myeloablative conditioning fared poorly, with 1-year overall actuarial survival of 44% compared with 77% for all other patients (P = .007). In multivariate analysis, age 50 years and over at transplantation was the only significant independent unfavorable risk factor for survival post-HCT (hazard ratio 2.71, 95% confidence interval 1.16-6.34, P = .02). This study shows a clear increase in annual numbers of allogeneic HCT performed for CM in Australia and New Zealand in recent years. Five-year survival was favorable compared with international studies, but for older recipients who received myeloablative conditioning, mortality risk was elevated.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mielofibrose Primária/mortalidade , Mielofibrose Primária/terapia , Sistema de Registros , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Fatores Etários , Idoso , Austrália/epidemiologia , Doença Crônica , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Condicionamento Pré-Transplante/efeitos adversos , Transplante Homólogo
10.
BMC Sports Sci Med Rehabil ; 14(1): 167, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064618

RESUMO

PURPOSE: Impaired quality of life (QOL) including reduced physical fitness is a recognized late effect of hemopoietic cell transplantation (HCT). Guided exercise and mindfulness-based stress management (MBSM) programs have shown promise, mainly in the inpatient setting. We aimed to examine the feasibility of a virtual, home-based, combined exercise and MBSM program. METHODS: Patients attending post-HCT clinic were invited to participate in this single-arm pre-post study. Eligibility criteria included age 18-75 years, > 6 months post allogeneic HCT. Consented participants attended an in-person session, followed by weekly exercise and MBSM training for 6 weeks via videoconferencing. Assessments were performed pre-training, and at 3-, 6- and 12-months and compared using a linear mixed effects model. RESULTS: 21 of 24 patients consenting to the study completed the program (median age 56 years [IQR 46-62], median time post-HCT 37 months [IQR 26-46]). Six-minute walk test scores were significantly higher at 3 (mean difference 79.6, 95%CI 28-131, ES 0.55) and 12 months (mean difference 48.4, 95%CI 13-84, ES 0.33) compared to baseline. Sit-to-stand test was significantly higher at 3 (mean difference 4.4, 95%CI 1.4-7.4, ES 0.68) and 12 months (mean difference 3.9, 95%CI 0.24-7.6, ES 0.61). Dominant hand grip was significantly stronger at 3 (mean difference 0.16, 95%CI 0.04-0.28, ES 0.45), and 12 months (mean difference 0.21, 95%CI 0.08-0.24, ES 0.62). Significantly higher FACT-BMT total (mean difference 6.9, 95%CI 1.5-12.4, ES 0.49) and FACT-G scores (mean difference 5.2, 95%CI 1.4-9.1, ES 0.48) were found at 3 months. Over 80% of participants rated the virtual combined modal program highly and no adverse events were reported. CONCLUSION: A 6-week virtual, home-based exercise and MBSM program was an acceptable, and potentially effective intervention for sustained improvement of some physical capacity and QOL outcomes in HCT survivors. Virtual-based healthcare service is highly relevant particularly during pandemics. To our knowledge, this study has the longest follow-up observation period for Internet based combined modality training program reported to date and warrants additional investigation. Trial Registration Research protocol approved by St Vincent's Hospital Ethics Committee (HREC 12/SVH/175), approved 27/09/2012, trial commenced 24/05/13 and the first participant 07/06/13. Retrospectively registered with ANZCTR (ACTRN12613001054707) 23/09/2013.

11.
Ann Clin Transl Neurol ; 9(2): 206-220, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35106961

RESUMO

OBJECTIVE: Autologous haematopoietic stem cell transplantation (AHSCT) has the potential to induce sustained periods of disease remission in multiple sclerosis (MS), which is an inflammatory disease of the central nervous system (CNS) characterised by demyelination and axonal degeneration. However, the mechanisms associated with durable treatment responses in MS require further elucidation. METHODS: To characterise the longer term immune reconstitution effects of AHSCT at 24 and 36 months (M) post-transplant, high-dimensional immunophenotyping of peripheral blood mononuclear cells from 22 MS patients was performed using two custom-designed 18-colour flow cytometry panels. RESULTS: The higher baseline frequencies of specific pro-inflammatory immune cells (T-helper-17 (Th17) cells, mucosal-associated invariant T-cells and CNS-homing T-conventional (T-conv) cells observed in MS patients were decreased post-AHSCT by 36M. This was accompanied by a post-AHSCT increase in frequencies and absolute counts of immunoregulatory CD56hi natural killer cells at 24M and terminally differentiated CD8+ CD28- CD57+ cells until 36M. A sustained increase in the proportion of naïve B-cells, with persistent depletion of memory B-cells and plasmablasts was observed until 36M. Reconstitution of the B-cell repertoire was accompanied by a reduction in the frequency of circulating T-follicular helper cells (cTfh) expressing programmed cell death-1 (PD1+ ) at 36M. Associations between frequency dynamics and clinical outcomes indicated only responder patients to exhibit a decrease in Th17, CNS-homing T-conv and PD1+ cTfh pro-inflammatory subsets at 36M, and an increase in CD39+ T-regulatory cells at 24M. INTERPRETATION: AHSCT induces substantial recalibration of pro-inflammatory and immunoregulatory components of the immune system of MS patients for up to 36M post-transplant.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucócitos Mononucleares , Esclerose Múltipla/sangue , Esclerose Múltipla/imunologia , Esclerose Múltipla/terapia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Adulto Jovem
12.
BMC Genomics ; 12: 138, 2011 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-21375780

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are post-transcriptional regulators of mRNA expression and are involved in numerous cellular processes. Consequently, miRNAs are an important component of gene regulatory networks and an improved understanding of miRNAs will further our knowledge of these networks. There is a many-to-many relationship between miRNAs and mRNAs because a single miRNA targets multiple mRNAs and a single mRNA is targeted by multiple miRNAs. However, most of the current methods for the identification of regulatory miRNAs and their target mRNAs ignore this biological observation and focus on miRNA-mRNA pairs. RESULTS: We propose a two-step method for the identification of many-to-many relationships between miRNAs and mRNAs. In the first step, we obtain miRNA and mRNA clusters using a combination of miRNA-target mRNA prediction algorithms and microarray expression data. In the second step, we determine the associations between miRNA clusters and mRNA clusters based on changes in miRNA and mRNA expression profiles. We consider the miRNA-mRNA clusters with statistically significant associations to be potentially regulatory and, therefore, of biological interest. CONCLUSIONS: Our method reduces the interactions between several hundred miRNAs and several thousand mRNAs to a few miRNA-mRNA groups, thereby facilitating a more meaningful biological analysis and a more targeted experimental validation.


Assuntos
MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Mensageiro/genética , Algoritmos , Análise por Conglomerados , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Modelos Lineares , Análise Multivariada
13.
Am J Hematol ; 86(1): 2-11, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20981674

RESUMO

MicroRNAs are short ribonucleic acids (RNAs) that play an important role in many aspects of cellular biology such as differentiation and apoptosis, due to their role in the regulation of gene expression. Using microRNA microarrays, we characterized the microRNA gene expression of 27 patients with acute myeloid leukemia (AML) with normal cytogenetics, focusing on the microRNAs differentially expressed between the M1 and M5 French-American-British (FAB) subtypes. An accurate delineation of these two AML entities was observed based on the expression of 12 microRNAs. We hypothesized that these microRNAs may potentially be involved in the differentiation block of M1 blasts and consequently monocytic differentiation. Using publically available mRNA data and microRNA target prediction software, we identified several key myeloid factors that may be targeted by our candidate microRNAs. The expression changes of the candidate microRNAs during monocytic differentiation of AML cell lines treated with Vitamin D and phorbol 12-myristate 13-acetate were examined. All six candidate microRNAs were significantly down-regulated over the time course by quantitative reverse transcriptase polymerase chain reaction suggesting a link between these microRNAs and monocytic differentiation. To further characterize these microRNAs, we confirmed by luciferase assays that these microRNA target several key myeloid factors such as MAFB, IRF8, and KLF4 identifying a possible mechanism for the control of differentiation by these microRNAs.


Assuntos
Leucemia Mieloide Aguda/genética , MicroRNAs/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Citogenética , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Fator 4 Semelhante a Kruppel , Leucemia Mieloide Aguda/patologia , Masculino , MicroRNAs/metabolismo , Análise em Microsséries , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
14.
Nucleic Acids Res ; 37(8): e60, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19295134

RESUMO

Over the past decade, a class of small RNA molecules called microRNAs (miRNAs) has been shown to regulate gene expression at the post-transcription stage. While early work focused on the identification of miRNAs using a combination of experimental and computational techniques, subsequent studies have focused on identification of miRNA-target mRNA pairs as each miRNA can have hundreds of mRNA targets. The experimental validation of some miRNAs as oncogenic has provided further motivation for research in this area. In this article we propose an odds-ratio (OR) statistic for identification of regulatory miRNAs. It is based on integrative analysis of matched miRNA and mRNA time-course microarray data. The OR-statistic was used for (i) identification of miRNAs with regulatory potential, (ii) identification of miRNA-target mRNA pairs and (iii) identification of time lags between changes in miRNA expression and those of its target mRNAs. We applied the OR-statistic to a cancer data set and identified a small set of miRNAs that were negatively correlated to mRNAs. A literature survey revealed that some of the miRNAs that were predicted to be regulatory, were indeed oncogenic or tumor suppressors. Finally, some of the predicted miRNA targets have been shown to be experimentally valid.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Algoritmos , Linhagem Celular Tumoral , Humanos , Cinética , Neoplasias/genética , Razão de Chances
15.
Front Immunol ; 12: 782935, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35126353

RESUMO

Autologous haematopoietic stem cell transplantation (AHSCT) is a therapeutic option for haematological malignancies, such as non-Hodgkin's lymphoma (NHL), and more recently, for autoimmune diseases, such as treatment-refractory multiple sclerosis (MS). The immunological mechanisms underlying remission in MS patients following AHSCT likely involve an anti-inflammatory shift in the milieu of circulating cytokines. We hypothesised that immunological tolerance in MS patients post-AHSCT is reflected by an increase in anti-inflammatory cytokines and a suppression of proinflammatory cytokines in the patient blood. We investigated this hypothesis using a multiplex-ELISA assay to compare the concentrations of secreted cytokine in the peripheral blood of MS patients and NHL patients undergoing AHSCT. In MS patients, we detected significant reductions in proinflammatory T helper (Th)17 cytokines interleukin (IL)-17, IL-23, IL-1ß, and IL-21, and Th1 cytokines interferon (IFN)γ and IL-12p70 in MS patients from day 8 to 24 months post-AHSCT. These changes were not observed in the NHL patients despite similar pre-conditioning treatment for AHSCT. Some proinflammatory cytokines show similar trends in both cohorts, such as IL-8 and tumour necrosis factor (TNF)-α, indicating a probable treatment-related AHSCT response. Anti-inflammatory cytokines (IL-10, IL-4, and IL-2) were only transiently reduced post-AHSCT, with only IL-10 exhibiting a significant surge at day 14 post-AHSCT. MS patients that relapsed post-AHSCT exhibited significantly elevated levels of IL-17 at 12 months post-AHSCT, unlike non-relapse patients which displayed sustained suppression of Th17 cytokines at all post-AHSCT timepoints up to 24 months. These findings suggest that suppression of Th17 cytokines is essential for the induction of long-term remission in MS patients following AHSCT.


Assuntos
Citocinas/sangue , Esclerose Múltipla/sangue , Adulto , Idoso , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Interleucina-12/sangue , Interleucinas/sangue , Linfoma não Hodgkin/sangue , Masculino , Pessoa de Meia-Idade , Células Th17/metabolismo , Transplante Autólogo/efeitos adversos , Adulto Jovem
16.
Blood Cell Ther ; 4(Spec Edition): S14-S19, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36713471

RESUMO

Standardization and formal accreditation of practices related to hematopoietic stem cell transplantation (HSCT) and therapies using hematopoietic-derived cellular products aim to promote quality in clinical and laboratory practice and provide knowledge to all stakeholders of centers. This article refers to three aspects of these processes starting with the importance of accurate viable CD 34 enumeration in HSCT. A highly accurate method of enumeration and a robust EQAS program is required, especially during the current COVID-19 pandemic. The second section shares experiences with FACT-JACIE accreditation at the Singapore General Hospital demonstrating how accreditation is part of continuous improvement and not only a destination. This journey can be difficult in many HSCT centers of low- and middle-income countries (LMICs) because of the intensive and rigorous requirements of the internationally accredited models. Hence, in LMICs, a staged movement toward establishing such standards must be considered. This approach is presented in the third section of the article with data on the current situation in countries reporting to the APBMT registry.

17.
Leukemia ; 35(7): 1933-1948, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33262524

RESUMO

Pharmacological inhibition of MDM2/4, which activates the critical tumor suppressor p53, has been gaining increasing interest as a strategy for the treatment of acute myeloid leukemia (AML). While clinical trials of MDM2 inhibitors have shown promise, responses have been confined to largely molecularly undefined patients, indicating that new biomarkers and optimized treatment strategies are needed. We previously reported that the microRNA miR-10a is strongly overexpressed in some AML, and demonstrate here that it modulates several key members of the p53/Rb network, including p53 regulator MDM4, Rb regulator RB1CC1, p21 regulator TFAP2C, and p53 itself. The expression of both miR-10a and its downstream targets were strongly predictive of MDM2 inhibitor sensitivity in cell lines, primary AML specimens, and correlated to response in patients treated with both MDM2 inhibitors and cytarabine. Furthermore, miR-10a inhibition induced synergy between MDM2 inhibitor Nutlin-3a and cytarabine in both in vitro and in vivo AML models. Mechanistically this synergism primarily occurs via the p53-mediated activation of cytotoxic apoptosis at the expense of cytoprotective autophagy. Together these findings demonstrate that miR-10a may be useful as both a biomarker to identify patients most likely to respond to cytarabine+MDM2 inhibition and also a druggable target to increase their efficacy.


Assuntos
Biomarcadores Tumorais/metabolismo , Leucemia Mieloide Aguda/metabolismo , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Citarabina/farmacologia , Feminino , Humanos , Imidazóis/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Camundongos , Camundongos Endogâmicos NOD , Piperazinas/farmacologia
18.
Front Immunol ; 12: 638709, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025648

RESUMO

Background: Behçet's Disease (BD) is an autoimmune disease mostly presenting with recurrent oral and genital aphthosis, and uveitis. Patients are rarely refractory to immunosuppressive treatments. Autologous hematopoietic stem cell transplantation (aHSCT) is a standard of care in other autoimmune diseases. Some patients with BD have been treated with aHSCT based on compassionate use. Objectives: Evaluate the outcome of aHSCT in adult patients with BD treated in member centers of the European Society for Blood and Marrow Transplantation (EBMT). Methods: Adults who received aHSCT primarily for BD were identified retrospectively in the EBMT registry and/or in published literature. Data were extracted from either medical records of the patient or from publications. Results: Eight out of 9 cases reported to the registry and extracted data of 2 further patients from literature were analyzed. Four were female, median age at onset of BD was 24y (range 9-50). Median age at aHSCT was 32y (27-51). Patients had received median 4 (2-11) previous lines of therapy (89% corticosteroids, 50% methotrexate, anti-TNFα therapy or cyclophosphamide). All patients had active disease before mobilization. Conditioning regimen was heterogeneous. Median follow-up was 48 months (range 6-240). No treatment-related mortality was reported. This procedure induced complete remission (CR) in 80%, partial remission in 10% and lack of response in 10% of the patients. Relapse rate was 30% (2 relapses in patients in CR and 1 relapse in the patient in PR) with panuveitis (n=1), aphthosis (n=2) and arthralgia (n=1). Six patients were in CR. No late complications were reported. Conclusion: aHSCT has an acceptable safety profile and represents a feasible and relatively effective procedure in severe and conventional treatment-resistant cases of BD and has the potential to stabilize BD in patients with life-threatening involvements.


Assuntos
Síndrome de Behçet/terapia , Transplante de Células-Tronco Hematopoéticas , Adulto , Síndrome de Behçet/mortalidade , Europa (Continente) , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Estudos Retrospectivos , Inquéritos e Questionários , Análise de Sobrevida , Transplante Autólogo , Resultado do Tratamento
19.
Sci Adv ; 7(3)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33523875

RESUMO

Terminally differentiated murine osteocytes and adipocytes can be reprogrammed using platelet-derived growth factor-AB and 5-azacytidine into multipotent stem cells with stromal cell characteristics. We have now optimized culture conditions to reprogram human adipocytes into induced multipotent stem (iMS) cells and characterized their molecular and functional properties. Although the basal transcriptomes of adipocyte-derived iMS cells and adipose tissue-derived mesenchymal stem cells were similar, there were changes in histone modifications and CpG methylation at cis-regulatory regions consistent with an epigenetic landscape that was primed for tissue development and differentiation. In a non-specific tissue injury xenograft model, iMS cells contributed directly to muscle, bone, cartilage, and blood vessels, with no evidence of teratogenic potential. In a cardiotoxin muscle injury model, iMS cells contributed specifically to satellite cells and myofibers without ectopic tissue formation. Together, human adipocyte-derived iMS cells regenerate tissues in a context-dependent manner without ectopic or neoplastic growth.


Assuntos
Azacitidina , Fator de Crescimento Derivado de Plaquetas , Adipócitos , Tecido Adiposo , Animais , Azacitidina/farmacologia , Diferenciação Celular , Células Cultivadas , Humanos , Camundongos , Células-Tronco Multipotentes , Músculos
20.
J Cell Biochem ; 109(2): 406-16, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19950204

RESUMO

This study addresses the role of bone morphogenetic protein-7 (BMP-7) in chondrogenic and osteogenic differentiation of human bone marrow multipotent mesenchymal stromal cells (BM MSCs) in vitro. BM MSCs were expanded and differentiated in the presence or absence of BMP-7 in monolayer and three-dimensional cultures. After 3 days of stimulation, BMP-7 significantly inhibited MSC growth in expansion cultures. When supplemented in commonly used induction media for 7-21 days, BMP-7 facilitated both chondrogenic and osteogenic differentiation of MSCs. This was evident by specific gene and protein expression analyses using real-time PCR, Western blot, histological, and immunohistochemical staining. BMP-7 supplementation appeared to enhance upregulation of lineage-specific markers, such as type II and type IX collagens (COL2A1, COL9A1) in chondrogenic and secreted phosphoprotein 1 (SPP1), osteocalcin (BGLAP), and osterix (SP7) in osteogenic differentiation. BMP-7 in the presence of TGF-beta3 induced superior chondrocytic proteoglycan accumulation, type II collagen, and SOX9 protein expression in alginate and pellet cultures compared to either factor alone. BMP-7 increased alkaline phosphatase activity and dose-dependently accelerated calcium mineralization of osteogenic differentiated MSCs. The potential of BMP-7 to promote adipogenesis of MSCs was restricted under osteogenic conditions, despite upregulation of adipocyte gene expression. These data suggest that BMP-7 is not a singular lineage determinant, rather it promotes both chondrogenic and osteogenic differentiation of MSCs by co-ordinating with initial lineage-specific signals to accelerate cell fate determination. BMP-7 may be a useful enhancer of in vitro differentiation of BM MSCs for cell-based tissue repair.


Assuntos
Adipogenia/fisiologia , Proteína Morfogenética Óssea 7/metabolismo , Condrogênese/fisiologia , Células-Tronco Mesenquimais/citologia , Osteogênese/fisiologia , Adipogenia/efeitos dos fármacos , Alginatos/farmacologia , Fosfatase Alcalina/metabolismo , Antígenos de Diferenciação/fisiologia , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Proteína Morfogenética Óssea 7/farmacologia , Calcificação Fisiológica/fisiologia , Técnicas de Cultura de Células , Linhagem da Célula , Células Cultivadas , Condrogênese/efeitos dos fármacos , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/farmacologia , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/fisiologia , Osteogênese/efeitos dos fármacos , Proteoglicanas/biossíntese , Fatores de Transcrição SOX9/fisiologia , Células Estromais/citologia , Células Estromais/fisiologia , Fator de Crescimento Transformador beta3/farmacologia
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