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Background & Aims: Although primary biliary cholangitis (PBC) is considered a rare disorder, accurate determination of its incidence and prevalence remains challenging due to limited comprehensive population-based registries. We aimed to assess the incidence and prevalence of PBC in the Netherlands over time through the nationwide Dutch PBC Cohort Study (DPCS). Methods: DPCS retrospectively included every identifiable patient with PBC in the Netherlands from 1990 onwards in all 71 Dutch hospitals. Incidence and prevalence were assessed between 2008-2018 by Poisson regression between sex and age groups over time. Results: On the 1st of January 2008, there were 1,458 patients with PBC in the Netherlands. Between 2008-2018, 2,187 individuals were newly diagnosed, 46 were transplanted and 468 died. The yearly incidence of PBC in 2008 was 1.38, increasing to 1.74 per 100,000 persons in 2018. When compared to those aged <45 years, females aged 45-64 years (adjusted incidence rate ratio 4.21, 95% CI 3.76-4.71, p <0.001) and males ≥65 years (adjusted incidence rate ratio 14.41, 95% CI 9.62-21.60, p <0.001) were at the highest risk of being diagnosed with PBC. The male-to-female ratio of patients newly diagnosed with PBC during the study period was 1:14 in those <45 years, 1:10 in patients aged 45-64 years, and 1:4 in those ≥65 years. Point prevalence increased from 11.9 in 2008 to 21.5 per 100,000 persons in 2018. Average annual percent change in this time period was 5.94% (95% CI 5.77-6.15, p <0.05), and was the highest among the population aged ≥65 years (5.69%, 95% CI 5.32-6.36, p <0.001). Conclusions: In this nationwide cohort study, we observed an increase in both the incidence and prevalence of PBC in the Netherlands over the past decade, with marked age and sex differences. Impact and implications: This nationwide Dutch primary biliary cholangitis (PBC) Cohort Study, including all hospitals in the Netherlands, showed that the incidence and prevalence of PBC have increased over the last decade. The age-dependent PBC incidence rate differed for males (highest risk ≥65 years) and females (highest risk between 45 and 65 years), which may be related to a difference in the timing of exposure to environmental triggers of PBC. The largest increase in PBC prevalence over time was observed in the population aged ≥65 years, which may have implications for the use of second-line therapies. These results therefore indicate that further studies are needed to elaborate on the advantages and disadvantages of add-on therapies in the elderly population.
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BACKGROUND: Autoimmune hepatitis (AIH) is a rare, chronic inflammatory disease of the liver. The treatment goal is reaching complete biochemical response (CR), defined as the normalisation of aspartate and alanine aminotransferases and immunoglobulin gamma. Ongoing AIH activity can lead to fibrosis and (decompensated) cirrhosis. Incomplete biochemical response is the most important risk factor for liver transplantation or liver-related mortality. First-line treatment consists of a combination of azathioprine and prednisolone. If CR is not reached, tacrolimus (TAC) or mycophenolate mofetil (MMF) can be used as second-line therapy. Both products are registered for the prevention of graft rejection in solid organ transplant recipients. The aim of this study is to compare the effectiveness and safety of TAC and MMF as second-line treatment for AIH. METHODS: The TAILOR study is a phase IIIB, multicentre, open-label, parallel-group, randomised (1:1) controlled trial performed in large teaching and university hospitals in the Netherlands. We will enrol 86 patients with AIH who have not reached CR after at least 6 months of treatment with first-line therapy. Patients are randomised to TAC (0.07 mg/kg/day initially and adjusted by trough levels) or MMF (max 2000 mg/day), stratified by the presence of cirrhosis at inclusion. The primary endpoint is the difference in the proportion of patients reaching CR after 12 months. Secondary endpoints include the difference in the proportion of patients reaching CR after 6 months, adverse effects, difference in fibrogenesis, quality of life and cost-effectiveness. DISCUSSION: This is the first randomised controlled trial comparing two second-line therapies for AIH. Currently, second-line treatment is based on retrospective cohort studies. The rarity of AIH is the main issue in clinical research for alternative treatment options. The results of this trial can be implemented in existing international clinical guidelines. TRIAL REGISTRATION: ClinicalTrials.gov NCT05221411 . Retrospectively registered on 3 February 2022; EudraCT number 2021-003420-33. Prospectively registered on 16 June 2021.
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Hepatite Autoimune , Tacrolimo , Humanos , Tacrolimo/efeitos adversos , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/tratamento farmacológico , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Imunossupressores/efeitos adversos , Ácido Micofenólico/efeitos adversos , Inibidores Enzimáticos/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase III como AssuntoRESUMO
BACKGROUND & AIMS: Patients with autoimmune hepatitis (AIH) almost invariably require lifelong immunosuppressive treatment. There is genuine concern about the efficacy and tolerability of the current standard combination therapy of prednisolone and azathioprine. Mycophenolate mofetil (MMF) has emerged as an alternative option. The aim of this study was to compare MMF to azathioprine as induction therapy for AIH. METHODS: In this 24-week, prospective, randomised, open-label, multicentre superiority trial, 70 patients with treatment-naive AIH received either MMF or azathioprine, both in combination with prednisolone. The primary endpoint was biochemical remission defined as normalisation of serum levels of alanine aminotransferase and IgG after 24 weeks of treatment. Secondary endpoints included safety and tolerability. RESULTS: Seventy patients (mean 57.9 years [SD 14.0]; 72.9% female) were randomly assigned to the MMF plus prednisolone (n = 39) or azathioprine plus prednisolone (n = 31) group. The primary endpoint was met in 56.4% and 29.0% of patients assigned to the MMF group and the azathioprine group, respectively (difference, 27.4 percentage points; 95% CI 4.0 to 46.7; p = 0.022). The MMF group exhibited higher complete biochemical response rates at 6 months (72.2% vs. 32.3%; p = 0.004). No serious adverse events occurred in patients who received MMF (0%) but serious adverse events were reported in four patients who received azathioprine (12.9%) (p = 0.034). Two patients in the MMF group (5.1%) and eight patients in the azathioprine group (25.8%) discontinued treatment owing to adverse events or serious adverse events (p = 0.018). CONCLUSIONS: In patients with treatment-naive AIH, MMF with prednisolone led to a significantly higher rate of biochemical remission at 24 weeks compared to azathioprine combined with prednisolone. Azathioprine use was associated with more (serious) adverse events leading to cessation of treatment, suggesting superior tolerability of MMF. IMPACT AND IMPLICATIONS: This randomised-controlled trial directly compares azathioprine and mycophenolate mofetil, both in combination with prednisolone, for the induction of biochemical remission in treatment-naive patients with autoimmune hepatitis. Achieving complete remission is desirable to prevent disease progression. Patients assigned to the mycophenolate mofetil group reached biochemical remission more often and experienced fewer adverse events. The findings in this trial may contribute to the re-evaluation of international guidelines for the standard of care in treatment-naive patients with autoimmune hepatitis. TRIAL REGISTRATION NUMBER: #NCT02900443.
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Azatioprina , Hepatite Autoimune , Humanos , Feminino , Masculino , Azatioprina/uso terapêutico , Ácido Micofenólico/efeitos adversos , Hepatite Autoimune/tratamento farmacológico , Estudos Prospectivos , Resultado do Tratamento , Imunossupressores/efeitos adversos , Prednisolona/efeitos adversos , Indução de RemissãoRESUMO
BACKGROUND: Currently, the standard therapy for autoimmune hepatitis (AIH) consists of a combination of prednisolone and azathioprine. However, 15% of patients are intolerant to azathioprine which necessitates cessation of azathioprine or changes in therapy. In addition, not all patients achieve complete biochemical response (CR). Uncontrolled data indicate that mycophenolate mofetil (MMF) can induce CR in a majority of patients. Better understanding of first-line treatment and robust evidence from randomised clinical trials are needed. The aim of this study was to explore the potential benefits of MMF as compared to azathioprine, both combined with prednisolone, as induction therapy in a randomised controlled trial in patients with treatment-naive AIH. METHODS: CAMARO is a randomised (1:1), open-label, parallel-group, multicentre superiority trial. All patients with AIH are screened for eligibility. Seventy adult patients with AIH from fourteen centres in the Netherlands and Belgium will be randomised to receive MMF or azathioprine. Both treatment arms will start with prednisolone as induction therapy. The primary outcome is biochemical remission, defined as serum levels of alanine aminotransferase and immunoglobulin G below the upper limit of normal. Secondary outcomes include safety and tolerability of MMF and azathioprine, time to remission, changes in Model For End-Stage Liver Disease (MELD)-score, adverse events, and aspects of quality of life. The study period will last for 24 weeks. DISCUSSION: The CAMARO trial investigates whether treatment with MMF and prednisolone increases the proportion of patients in remission compared with azathioprine and prednisolone as the current standard treatment strategy. In addition, we reflect on the challenges of conducting a randomized trial in rare diseases. TRIAL REGISTRATION: EudraCT 2016-001038-91 . Prospectively registered on 18 April 2016.
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Doença Hepática Terminal , Hepatite Autoimune , Adulto , Humanos , Ácido Micofenólico/efeitos adversos , Azatioprina/efeitos adversos , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/tratamento farmacológico , Qualidade de Vida , Imunossupressores/efeitos adversos , Resultado do Tratamento , Índice de Gravidade de Doença , Prednisolona/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como AssuntoRESUMO
We describe a case of a previous healthy 20-year-old male athlete who presented with an atypical clinical profile with multiorgan involvement within five weeks after confirmed SARS-CoV-2 infection, suggestive for multisystem inflammatory syndrome (MIS); MIS is a rare, potentially life-threatening complication associated with SARS-CoV-2. MIS shares similar clinical features compatible with several overlapping lifethreatening hyperinflammatory syndromes, such as incomplete Kawasaki Disease (KD) and toxic shock syndrome (TSS) associated to a cytokine storm suggestive of a macrophage activation syndrome (MAS) without fulfilling the criteria for hemophagocytic lymphohistiocytosis (HLH), that may create a great challenge to distinguish between them. MIS should promptly be considered and treated, as uncontrolled MIS has a high mortality. In MIS cardiac involvement, heart failure may present as an additional problem, especially because volume loading is advised in accordance with proposed therapy. Carefully monitoring of the respiratory and cardiac status in response of resuscitation is therefore warranted.
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Shwachman-Diamond syndrome (SDS) is a rare autosomal recessive disease characterized by exocrine pancreatic insufficiency with malabsorption, malnutrition, growth failure and bone marrow failure. Furthermore, duodenal inflammatory enteropathy features may be present. For the first time, we report here a SDS case that is also diagnosed with inflammatory bowel disease (IBD). He was diagnosed with SDS at the age of two based on poor growth, severe exocrine pancreatic insufficiency with steatorrhea, neutropenia, recurrent infections and thoracic skeletal abnormalities. Ileocolonoscopy and histopathology revealed colonic Crohn's disease at the age of sixteen. Our report may encourage further studies elucidating the possible association between the SDS genetic defect and inflammatory bowel disease.
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Doenças Inflamatórias Intestinais/complicações , Síndrome de Shwachman-Diamond/complicações , Humanos , Masculino , Adulto JovemRESUMO
BACKGROUND: High white blood cell count at presentation is an unfavorable prognostic factor for treatment outcome in intermediate cytogenetic risk acute myeloid leukemia. Since the impact of white blood cell count on outcome of subgroups defined by the molecular markers NPMc(+) and FLT3-internal tandem duplication (ITD) is unknown, we addressed this issue. DESIGN AND METHODS: We studied the effect of white blood cell count on outcome in a clinically and molecularly well-defined cohort of 525 patients with acute myeloid leukemia using these molecular markers. In addition, since an increased white blood cell count has been associated with an increased FLT3-ITD/FLT3 (wild-type) ratio, we investigated whether the effect of white blood cell count on outcome could be explained by the FLT3-ITD/FLT3 ratio. RESULTS: This analysis revealed that white blood cell count had no impact on outcome in patients with the genotypic combinations 'NPMc(+) without FLT3-ITD' and 'NPM1 wild-type with or without FLT3-ITD'. In contrast, white blood cell count had a significant impact on complete remission rate (P=0.034), event-free survival (P=0.009) and overall survival (P<0.001) in patients with the genotypic combination 'NPMc(+) with FLT3-ITD'. A FLT3-ITD/FLT3 ratio greater than 1 was also associated with a reduced complete remission rate (P=0.066) and significantly reduced event-free survival (P= 0.001) and overall survival (P=0.001) in patients with the genotypic combination 'NPMc(+) with FLT3-ITD'. Multivariable analysis revealed that white blood cell count and FLT3-ITD/FLT3 ratio were independent prognostic indicators for outcome in the subgroup with the genotypic combination 'NPMc(+) with FLT3-ITD'. CONCLUSIONS: Our results demonstrate that both high white blood cell count and FLT3-ITD/FLT3 ratio are prognostic factors in patients with acute myeloid leukemia with the genotypic combination 'NPMc(+) with FLT3-ITD'.
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Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Contagem de Leucócitos , Mutação/genética , Proteínas Nucleares/genética , Tirosina Quinase 3 Semelhante a fms/genética , Adolescente , Adulto , Idoso , Citogenética , Humanos , Leucemia Mieloide Aguda/mortalidade , Pessoa de Meia-Idade , Nucleofosmina , Prognóstico , Fatores de Risco , Análise de Sobrevida , Adulto JovemRESUMO
VEGFA is considered one of the most important regulators of tumor-associated angiogenesis in cancer. In acute myeloid leukemia (AML) VEGFA is an independent prognostic factor for reduced overall and relapse-free survival. Transcriptional activation of the VEGFA promoter, a core mechanism for VEGFA regulation, has not been fully elucidated. We found a significant (P < 0.0001) inverse correlation between expression of VEGFA and AML1/RUNX1 in a large set of gene expression array data. Strikingly, highest VEGFA levels were demonstrated in AML blasts containing a t(8;21) translocation, which involves the AML1/RUNX1 protein (AML1/ETO). Overexpression of AML1/RUNX1 led to downregulation of VEGFA expression, whereas blocking of AML1/RUNX1 with siRNAs resulted in increased VEGFA expression. Cotransfection of AML1/RUNX1 and VEGFA promoter luciferase promoter constructs resulted in a decrease in VEGFA promoter activity. ChIP analysis shows a direct binding of AML1/RUNX1 to the promoter of VEGFA on three AML1/RUNX1 binding sites. Silencing of AML1/ETO caused a decrease in VEGFA mRNA expression and a decrease in secreted VEGFA protein levels in AML1/ETO-positive Kasumi-1 cells. Taken together, these data pinpoint to a model whereby in normal cells AML1/RUNX1 acts as a repressor for VEGFA, while in AML cells VEGFA expression is upregulated due to AML1/RUNX1 aberrations, for example, AML1/ETO. In conclusion, these observations give insight in the regulation of VEGFA at the mRNA level in AML.
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Subunidade alfa 2 de Fator de Ligação ao Core/biossíntese , Leucemia Mieloide Aguda/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Sítios de Ligação , Linhagem Celular Tumoral , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Inativação Gênica , Células HL-60 , Humanos , Leucemia Mieloide Aguda/genética , Mutação , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Proteína 1 Parceira de Translocação de RUNX1 , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Transcrição Gênica , Translocação Genética , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
High VEGFC mRNA expression of acute myeloid leukemia (AML) blasts is related to increased in vitro and in vivo drug resistance. Prognostic significance of VEGFC on long-term outcome and its associated gene expression profiles remain to be defined. We studied effect of VEGFC on treatment outcome and investigated gene expression profiles associated with VEGFC using microarray data of 525 adult and 100 pediatric patients with AML. High VEGFC expression appeared strongly associated with reduced complete remission rate (P = .004), reduced overall and event-free survival (OS and EFS) in adult AML (P = .002 and P < .001, respectively). Multivariable analysis established high VEGFC as prognostic indicator independent of cytogenetic risk, FLT3-ITD, NPM1, CEBPA, age, and white blood cell count (P = .038 for OS; P = .006 for EFS). Also, in pediatric AML high VEGFC was related to reduced OS (P = .041). A unique series of differentially expressed genes was identified that distinguished AML with high VEGFC from AML with low VEGFC, that is, 331 up-regulated genes (representative of proliferation, vascular endothelial growth factor receptor activity, signal transduction) and 44 down-regulated genes (eg, related to apoptosis) consistent with a role in enhanced chemoresistance. In conclusion, high VEGFC predicts adverse long-term prognosis and provides prognostic information in addition to well-known prognostic factors.
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Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Fator C de Crescimento do Endotélio Vascular/genética , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/diagnóstico , Contagem de Leucócitos , Pessoa de Meia-Idade , Análise Multivariada , Nucleofosmina , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Adulto JovemRESUMO
Acute myeloid leukemia (AML) has a different clinical and biologic behavior in patients at older age. To gain further insight into the molecular differences, we examined a cohort of 525 adults to compare gene expression profiles of the one-third of youngest cases (n = 175; median age 31 years) with the one-third of oldest cases (n = 175; median age 59 years). This analysis revealed that 477 probe sets were up-regulated and 492 probe sets were down-regulated with increasing age at the significance level of P < .00001. After validation with 2 independent AML cohorts, the 969 differentially regulated probe sets on aging could be pointed to 41 probe sets, including the tumor-suppressor gene CDKN2A (encoding p16(INK4A)). In contrast to the induced p16(INK4A) expression that is associated with physiologic aging, p16(INK4A) is down-regulated in AML samples of patients with increasing age. However, this was only noticed in the intermediate- and unfavorable-risk group and not in the favorable-risk group and the molecularly defined subset "NPM1 mutant without FLT3-ITD." Multivariate analysis revealed p16(INK4A), besides cytogenetic risk groups, as an independent prognostic parameter for overall survival in older patients. We conclude that, in addition to altered clinical and biologic characteristics, AML presenting at older age shows different gene expression profiles.
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Inibidor p16 de Quinase Dependente de Ciclina/genética , Perfilação da Expressão Gênica , Leucemia Mieloide Aguda/genética , RNA Mensageiro/genética , Adolescente , Adulto , Fatores Etários , Idoso , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Regulação para Baixo , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Pessoa de Meia-Idade , Nucleofosmina , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Adulto JovemRESUMO
Aging is generally considered to be the consequence of stem cell attrition caused by the activity of tumor suppressor pathways that censor potentially malignant clones by eliciting apoptosis or senescence. An important effector of aging is the cyclindependent kinase inhibitor p16(INK4a), which is also a known suppressor of cancer. The expression of p16(INK4a) is very low or absent in young organisms but increases with advancing age. We recently showed that, unlike healthy cells, acute myeloid leukemia (AML) derived blasts show a down-regulation of p16(INK4a) mRNA with increasing age. Based on this observation we hypothesize that suppression of defense mechanisms which protect older cells against cellular and DNA damage might facilitate oncogenesis in older individuals.
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Envelhecimento/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Regulação para Baixo/genética , Leucemia Mieloide Aguda/genética , RNA Mensageiro/genética , Envelhecimento/patologia , Envelhecimento/fisiologia , Apoptose/genética , Apoptose/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/fisiologia , Dano ao DNA/genética , Dano ao DNA/fisiologia , Regulação para Baixo/fisiologia , Humanos , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/fisiopatologia , Leucócitos/patologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/fisiologiaRESUMO
PURPOSE: We hypothesized that downstream effects of endogenous vascular endothelial growth factor (VEGF)/VEGF receptor signaling on acute myelogenous leukemia (AML) cell survival resulted in increased in vitro cellular drug resistance and a longer time to kill most leukemic cells in vivo upon drug exposure. EXPERIMENTAL DESIGN: In primary AML cells from pediatric patients, VEGFA and VEGFC mRNA expression and in vitro cellular resistance to nine cytotoxic drugs were studied. As in vivo equivalents for in vitro drug resistance, in vivo AML blast reduction upon drug exposure, measured as blast cell reduction on day 15 in the bone marrow and as time in days from diagnosis to complete remission (CR) were used. RESULTS: Increased endogenous VEGFC levels significantly correlated with increased in vitro resistance for six typical AML drugs in primary AML cells from pediatric patients. Patients with >5% blasts on day 15 showed a 12.9-fold increase in the median VEGFC level compared with patients with < or =5% blasts (P = 0.002). Time to reach CR was studied using linear regression analysis with VEGFC, age at diagnosis, sex, treatment protocol, FAB type, cytogenetic risk profile, and WBC counts as variables. There was a significant positive independent association between VEGFC levels and time to CR (b = 6.02, SE = 1.58, P < or = 0.0001, n = 72). CONCLUSIONS: These results suggest for the first time that higher endogenous VEGFC levels of AML cells are related to decreased in vitro and in vivo drug responsiveness.
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Leucemia Mieloide Aguda/genética , Fator C de Crescimento do Endotélio Vascular/genética , Adolescente , Adulto , Antineoplásicos/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Cariotipagem , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , RNA Mensageiro/genética , Medição de Risco , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
It has been hypothesized that the net expression of a gene is determined by the combined effects of various transcriptional system regulators (TSRs). However, characterizing the complexity of regulation of the transcriptome is a major challenge. Principal component analysis on 17,550 heterogeneous human microarray experiments revealed that 50 orthogonal factors (hereafter called TSRs) are able to capture 64% of the variability in expression in a wide range of experimental conditions and tissues. We identified gene clusters controlled in the same direction and show that gene expression can be conceptualized as a process influenced by a fairly limited set of TSRs. Furthermore, TSRs can be linked to biological functions, as we demonstrate a strong relation between TSR-related gene clusters and biological functionality as well as cellular localization, i.e. gene products of similarly regulated genes by a specific TSR are located in identical parts of a cell. Using 3,934 diverse mouse microarray experiments we found striking similarities in transcriptional system regulation between human and mouse. Our results give biological insights into regulation of the cellular transcriptome and provide a tool to characterize expression profiles with highly reliable TSRs instead of thousands of individual genes, leading to a >500-fold reduction of complexity with just 50 TSRs. This might open new avenues for those performing gene expression profiling studies.
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Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Elementos Reguladores de Transcrição , Transcrição Gênica/genética , Animais , Redes Reguladoras de Genes , Camundongos , Análise de Sequência com Séries de OligonucleotídeosRESUMO
Acute myeloid leukemia (AML) is a disease with a poor prognosis. It has been demonstrated that AML cells express the vascular endothelial growth factors, VEGFA and VEGFC, as well as kinase insert domain-containing receptor (VEGFR2), the main receptor for downstream effects, resulting in an autocrine pathway for cell survival. This study investigates the role of the VEGFR inhibitor PTK787/ZK 222584 in leukemic cell death, and the possibility of an additional effect on cell death by a chemotherapeutic drug, amsacrine. In three AML cell lines and 33 pediatric AML patient samples, we performed total cell-kill assays to determine the percentages of cell death achieved by PTK787/ZK 222584 and/or amsacrine. Both drugs induced AML cell death. Using a response surface analysis, we could show that, in cell lines as well as in primary AML blasts, an equal magnitude of leukemic cell death could be obtained when lower doses of the more toxic amsacrine were combined with low dosages of the less toxic VEGFR inhibitor. This study shows that PTK787/ZK 222584 might have more clinical potential in AML when combined with a chemotherapeutic drug such as amsacrine. In future, it will be interesting to study whether the complications and the long-term effects of chemotherapy can be reduced by lowering the dosages of amsacrine, and by replacing it with other drugs with lower toxicity profiles, such as PTK787/ZK 222584.
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Amsacrina/farmacologia , Antineoplásicos/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Ftalazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Citometria de Fluxo , Humanos , Leucemia Mieloide Aguda/patologia , Ftalazinas/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Piridinas/metabolismo , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
For accurate and reliable gene expression analysis, normalization of gene expression data against housekeeping genes (reference or internal control genes) is required. It is known that commonly used housekeeping genes (e.g. ACTB, GAPDH, HPRT1, and B2M) vary considerably under different experimental conditions and therefore their use for normalization is limited. We performed a meta-analysis of 13,629 human gene array samples in order to identify the most stable expressed genes. Here we show novel candidate housekeeping genes (e.g. RPS13, RPL27, RPS20 and OAZ1) with enhanced stability among a multitude of different cell types and varying experimental conditions. None of the commonly used housekeeping genes were present in the top 50 of the most stable expressed genes. In addition, using 2,543 diverse mouse gene array samples we were able to confirm the enhanced stability of the candidate novel housekeeping genes in another mammalian species. Therefore, the identified novel candidate housekeeping genes seem to be the most appropriate choice for normalizing gene expression data.