RESUMO
Internal tandem duplication of FLT3 juxtamembrane domain (FLT3-ITD)-positive acute myeloid leukemia (AML) leads to poor clinical outcomes after chemotherapy. We aimed to establish a cytarabine-resistant line from FLT3-ITD-positive MV4-11 (MV4-11-P) cells and examine the development of resistance. The FLT3-ITD mutation was retained in MV4-11-R; however, the protein was underglycosylated and less phosphorylated in these cells. Moreover, the phosphorylation of ERK1/2, Akt, MEK1/2 and p53 increased in MV4-11-R. The levels of Mcl-1 and p53 proteins were also elevated in MV4-11-R. A p53 D281G mutant emerged in MV4-11-R, in addition to the pre-existing R248W mutation. MV4-11-P and MV4-11-R showed similar sensitivity to cabozantinib, sorafenib, and MK2206, whereas MV4-11-R showed resistance to CI-1040 and idarubicin. MV4-11-R resistance may be associated with inhibition of Akt phosphorylation, but not ERK phosphorylation, after exposure to these drugs. The multi-kinase inhibitor cabozantinib inhibited FLT3-ITD signaling in MV4-11-R cells and MV4-11-R-derived tumors in mice. Cabozantinib effectively inhibited tumor growth and prolonged survival time in mice bearing MV4-11-R-derived tumors. Together, our findings suggest that Mcl-1 and Akt phosphorylation are potential therapeutic targets for p53 mutants and that cabozantinib is an effective treatment in cytarabine-resistant FLT3-ITD-positive AML.
Assuntos
Citarabina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Deleção de Genes , Mutação , Sequências de Repetição em Tandem , Proteína Supressora de Tumor p53/genética , Tirosina Quinase 3 Semelhante a fms/genética , Anilidas/farmacologia , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Análise Mutacional de DNA , Relação Dose-Resposta a Droga , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Redes e Vias Metabólicas , Piridinas/farmacologiaRESUMO
Growth arrest-specific protein 6 (Gas6) is a serum protein involved in granulocyte, platelet and endothelium interaction, and is implicated in both anti-inflammatory response as well as platelet/leukocytes activation. We investigated serum Gas6 level in different clinical manifestations of systemic lupus erythematosus (SLE). Data were collected in 83 patients with SLE and 40 non-lupus controls. The Gas6 levels were detected by enzyme-linked immunosorbent assay. Our results demonstrated that the Gas6 level was higher in SLE patients as compared to the non-lupus control subjects (SLE vs. non-lupus control, median [inter-quartile range (IQR)] 22.67 [19.40-28.60] vs. 18.97 [16.05-20.62] ng/mL, p < 0.01). Furthermore, Gas6 level was higher in patients with nephritis (nephritis vs. non-nephritis, median [IQR] 26.21 [21.17-31.61] vs. 22.22 [18.98-26.98] ng/mL, p = 0.03) and in patients with cutaneous vasculitis (vasculitis vs. non-vasculitis, median [IQR] 27.89 [23.24-34.26] vs. 22.30 [19.32-27.16] ng/mL, p = 0.03). Our results indicate that the serum Gas6 level is increased in SLE patients with lupus nephritis or cutaneous vasculitis, implicating a potential to serve as a SLE disease activity marker.
Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/sangue , Lúpus Eritematoso Sistêmico/sangue , Nefrite Lúpica/sangue , Vasculite/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Nefrite Lúpica/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Regulação para Cima , Vasculite/diagnósticoRESUMO
Genomic imprinting predominantly occurs in the placenta and brain. Few imprinted microRNAs have been identified in the brain, and their functional roles in the brain are not clear. Here we show paternal, but not maternal, expression of MIR125B2 in human but not mouse brain. Moreover, Mir125b-2m-/p- mice showed impaired learning and memory, and anxiety, whose functions were hippocampus-dependent. Hippocampal granule cells from Mir125b-2m-/p- mice displayed increased neuronal excitability, increased excitatory synaptic transmission, and decreased inhibitory synaptic transmission. Glutamate ionotropic receptor NMDA type subunit 2A (Grin2a), a key regulator of synaptic plasticity, was physically bound by miR-125b-2 and upregulated in the hippocampus of Mir125b-2m-/p- mice. Taken together, our findings demonstrate MIR125B2 imprinted in human but not mouse brain, mediated learning, memory, and anxiety, regulated excitability and synaptic transmission in hippocampal granule cells, and affected hippocampal expression of Grin2a. Our work provides functional mechanisms of a species-specific imprinted microRNA in the brain.
Assuntos
Hipocampo , MicroRNAs , Animais , Humanos , Camundongos , Hipocampo/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Transmissão Sináptica/fisiologiaRESUMO
BACKGROUND: Only a small proportion of women infected with human papillomavirus type 18 (HPV18) may progress to persistent infection and cervical neoplasia. This community-based cohort study aimed to assess associations with human leukocyte antigen (HLA) class II genotypes for natural infection of HPV18 and subsequent risk of cervical neoplasia. METHODS: Among 10,190 cytologically normal participants, 125 with HPV18 infection were identified by HPV blot kit. HPV18 viral load at study entry was examined by real-time polymerase chain reaction; persistent infection was defined as HPV18 infection at 2 consecutive examinations. RESULTS: There was a significant association between HLA-DRB1*0403 allele and high HPV18 viral load (>1000 copies in 50 ng of total DNA) at study entry (odds ratio [OR], 7.2; 95% confidence interval [CI], 2.0-25.2). After adjustment for age and viral load at study entry, haplotype HLA-DRB1*0405-DQA1*0301-DQB1*0302 was significantly associated with persistent HPV18 infection (OR, 13.3; 95% CI, 1.7-105.9). HLA-DRB1*0403 allele was also associated with a significantly increased risk of high-grade squamous intraepithelial lesion or cancer, showing a multivariate-adjusted hazard ratio (95% CI) of 18.1 (2.6-128.5). CONCLUSIONS: HLA-DRB1*0403 allele and HLA-DRB1*0405-DQA1*0301-DQB1*0302 haplotype may play important roles in determination of high viral load and persistent infection of HPV18 and subsequent cervical neoplasia risk.
Assuntos
Antígenos de Histocompatibilidade Classe II/genética , Papillomavirus Humano 18 , Infecções por Papillomavirus/genética , Displasia do Colo do Útero/genética , Estudos de Coortes , Feminino , Genótipo , Antígenos HLA/genética , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Carga ViralRESUMO
We previously reported that the anticancer activity of a botanical compound 10'(Z),13'(E),15'(E)-heptadecatrienylhydroquinone [HQ17(3)] was attributed to topoisomerase (Topo) IIα poisoning and the induction of oxidative damage. HQ17(3) irreversibly inhibits Topo IIα activity in vitro and is more cytotoxic in leukemia HL-60 cells than in Topo IIα-deficient variant HL-60/MX2 cells, which suggests that Topo IIα is a cellular target of HQ17(3). This study further characterizes the molecular mechanisms of the anticancer activity of HQ17(3). Proteomic analyses indicated that HQ17(3) reacted with Cys-427, Cys-733, and Cys-997 of recombinant Topo IIα in vitro, whereas it reacted with Cys-427 of cellular Topo IIα in Huh7 hepatoma cells. The modification of HQ17(3) inhibited Topo IIα catalytic activity, increased the Topo IIα-DNA cleavage complex, and caused the accumulation of DNA breakage. In Huh7 cells, HQ17(3) treatment caused prompt inhibition of DNA synthesis and consequently induced the expression of DNA damage-related genes DDIT3, GADD45A, and GADD45G. Topo IIα inhibition, apoptosis, and oxidative stress were found to account for cytotoxicity caused by HQ17(3). Pretreatment of Huh7 cells with N-acetylcysteine (NAC) partially attenuated mitochondrial membrane damage, DNA breakage, and caspase activation. However, NAC pretreatment did not diminish HQ17(3)-induced cell death. These results suggest that the anticancer activity of HQ17(3) is attributed significantly to Topo IIα poisoning. The structural feature of HQ17(3) can be used as a model for the design of Topo IIα inhibitors and anticancer drugs.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cisteína/química , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Quebras de DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Hidroquinonas/farmacologia , Antígenos de Neoplasias/metabolismo , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Citometria de Fluxo , Humanos , Hidroquinonas/química , Hidroquinonas/isolamento & purificação , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
The contribution of genetic factors to the memory is widely acknowledged. Research suggests that these factors include genes involved in the dopaminergic pathway, as well as the genes for brain-derived neurotrophic factor (BDNF) and methylenetetrahydrofolate reductase (MTHFR). The activity of the products of these genes is affected by single nucleotide polymorphisms (SNPs) within the genes. This study investigates the association between memory and SNPs in genes involved in the dopaminergic pathway, as well as in the BDNF and MTHFR genes, in a sample of healthy individuals. The sample includes 134 Taiwanese undergraduate volunteers of similar cognitive ability. The Chinese versions of the Wechsler Memory Scale (WMS-III) and Wechsler Adult Intelligence Scale (WAIS-III) were employed. Our findings indicate that the BDNF Met66Val polymorphism and dopamine receptor D3 (DRD3) Ser9Gly polymorphism are associated significantly with long-term auditory memory. Further analysis detects no significant associations in the other polymorphisms and indices. Future replicated studies with larger sample sizes, and studies that consider different ethnic groups, are encouraged.
Assuntos
Povo Asiático/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Memória/fisiologia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Receptores de Dopamina D3/genética , Estimulação Acústica , Adolescente , Cognição/fisiologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Humanos , Masculino , Testes Neuropsicológicos , Taiwan , Adulto JovemRESUMO
MicroRNA (miRNA) expression is reportedly associated with clinical outcomes in childhood acute lymphoblastic leukemia (ALL). Here, we aimed at investigating whether miRNA expression is associated with clinical outcomes in pediatric ALL patients treated with the Taiwan Pediatric Oncology Group (TPOG) protocols. The expression of 397 miRNAs was measured using stem-loop quantitative real-time polymerase chain reaction miRNA arrays in 60 pediatric ALL patients treated with TPOG-ALL-93 or TPOG-ALL-97 VHR (very high-risk) protocols. In order to identify prognosis-related miRNAs, original cohort was randomly split into the training and testing cohort in a 2:1 ratio, and univariate Cox proportional hazards regression was applied to identify associations between event-free survival (EFS) and expressions of miRNAs. Four prognosis-related miRNAs were selected and validated in another independent cohort composed of 103 patients treated with the TPOG-ALL-2002 protocol. Risk score, including the impact of four prognosis-related miRNAs, was calculated for each patients, followed by grouping patients into the high or low risk-score groups. Irrespective of the training, testing, or validation cohort, risk-score group was significantly associated with EFS and overall survival (OS). Risk-score group combining with clinical characteristics including the age onset (≥10 years), white blood cell counts (≥100 × 109/L), cell type (T- or B-cell), sex, and risk groups of the treatment protocols were used as predictors of EFS using the multivariate Cox proportional hazards regression. Results showed that the risk-score group was the strongest predictor. In the validation cohort, hazard ratios (HRs) of the risk-score group were 7.06 (95% CI=1.93-25.84, p-value =0.003) and 14.03 (95% CI=3.34-59.04, p-value =0.003) for EFS and OS, respectively. High risk-score group had higher risk of having poor prognosis and risk of death than that in the low risk group. Accuracy of the prediction model for 5-year EFS could reach 0.76. For the prediction of 5-year OS, accuracy was 0.75. In conclusion, a miRNA signature was associated with clinical outcomes in childhood ALL patients treated with TPOG protocols and might be a suitable prognostic biomarker.
RESUMO
MicroRNA-125b, the first microRNA to be identified, is known to promote cardiomyocyte maturation from embryonic stem cells; however, its physiological role remains unclear. To investigate the role of miR-125b in cardiovascular biology, cardiac-specific miR-125b-1 knockout mice were generated. We found that cardiac-specific miR-125b-1 knockout mice displayed half the miR-125b expression of control mice resulting in a 60% perinatal death rate. However, the surviving mice developed hearts with cardiac hypertrophy. The cardiomyocytes in both neonatal and adult mice displayed abnormal mitochondrial morphology. In the deficient neonatal hearts, there was an increase in mitochondrial DNA, but total ATP production was reduced. In addition, both the respiratory complex proteins in mitochondria and mitochondrial transcription machinery were impaired. Mechanistically, using transcriptome and proteome analysis, we found that many proteins involved in fatty acid metabolism were significantly downregulated in miR-125b knockout mice which resulted in reduced fatty acid metabolism. Importantly, many of these proteins are expressed in the mitochondria. We conclude that miR-125b deficiency causes a high mortality rate in neonates and cardiac hypertrophy in adult mice. The dysregulation of fatty acid metabolism may be responsible for the cardiac defect in the miR-125b deficient mice.
Assuntos
Cardiomegalia/etiologia , Predisposição Genética para Doença , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Morte Perinatal/etiologia , Animais , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Biologia Computacional , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Marcação de Genes , Estudos de Associação Genética , Testes de Função Cardíaca , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Mitocôndrias Cardíacas/genética , Mitocôndrias Cardíacas/metabolismo , Especificidade de Órgãos/genética , Fenótipo , Proteômica/métodos , Interferência de RNA , TranscriptomaRESUMO
Since the high degree of heritability of physiological traits was demonstrated by twin and adoption studies, contemporary researchers in the fields of clinical medicine, behavioral science, and genetics have acknowledged the crucial role of genetic factors in human physiology. The study described herein explores the association between physiological parameters and the dopaminergic system using molecular genetic techniques. A total of 558 Taiwanese female volunteers, ranging from 16 to 17 years, were recruited. Single nucleotide polymorphisms in genes involved in the dopaminergic pathway were selected for analysis. Systolic blood pressure and diastolic blood pressure were associated significantly with the catechol-O-methyltransferase (COMT) Val158Met polymorphism and the dopamine ß-hydroxylase (DBH) C1021T polymorphism. Furthermore, plasma uric acid was associated significantly with the COMT Val158Met polymorphism. Our study suggests the possible involvement of genetic polymorphisms in COMT and DBH in the regulation of blood pressure and plasma uric acid.
Assuntos
Pressão Sanguínea/genética , Dopamina/fisiologia , Polimorfismo Genético/genética , Ácido Úrico/sangue , Adolescente , Povo Asiático/genética , Feminino , Humanos , Vias Neurais/fisiologiaRESUMO
OBJECTIVES: This retrospective study evaluates the role of pharmacogenomic determinants in the treatment of childhood acute lymphoblastic leukemia (ALL) in the Taiwanese population. METHODS: A total of 105 childhood ALL patients received combined chemotherapy of different intensities based on risk-directed Taiwan Pediatric Oncology Group (TPOG)-ALL-93 protocols. Seventeen genetic polymorphisms in 13 pharmacogenomic targets were analyzed by PCR-based restriction fragment length polymorphism (RFLP) and sequence-specific oligonucleotide (SSO) probe hybridization. Pharmacogenomic polymorphisms were correlated with event-free survival (EFS) of patients, with confounding effects adjusted by multivariate regression. RESULTS: Three polymorphic alleles in the multi-drug resistance 1 (MDR1) ABCB1 gene, and homozygotic MDR1 2677GG, 3435CC, and 2677G-3435C genotypes were highly associated with a significant reduction in EFS in those patients treated by the standard risk (SR) protocol (TPOG-ALL-93-SR). The hazard ratios were 6.8 (p = 0.01), 21.7 (p = 0.009), and 6.8 (p = 0.01), respectively. CONCLUSIONS: Independent pharmacogenomic determinants associated with treatment outcome were identified in subsets of Taiwanese ALL patients.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Resistência a Medicamentos/genética , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Povo Asiático/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Análise Multivariada , Farmacogenética , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , TaiwanRESUMO
Human leukocyte antigen (HLA) class II molecules are associated with host immune responses against hepatitis B virus infection. Male gender is the apparent host factor when someone encounters with the severity of hepatitis. The aim of this study was to investigate the association of the most polymorphic HLA class II allele, human leukocyte antigen-DRB1, with the severity of hepatitis in male carriers of hepatitis B virus. In this prospective cohort study, a total of 204 carriers of hepatitis B virus (131 men and 73 women) who have been followed-up for more than 1 year at the outpatient clinic of a university hospital were collected consecutively. Fifty carriers of hepatitis B virus (group I) with alanine aminotransferase <2x upper limit of normal (mean follow-up 83.6 months) were compared with 154 chronic hepatitis B patients (group II) with alanine aminotransferase >/=2x upper limit of normal (mean follow-up 81.3 months). Alleles of HLA-DRB1 were typed by the polymerase chain reaction-sequence specific oligonucleotide probe hybridization and genotypes of hepatitis B virus by melting curve analysis. HLA-DRB1*1101 was found in 18% of group I versus 8% of group II in male carriers (OR 0.23, P = 0.020, after adjustment for age) and 4% versus 9.4% in female carriers (P = 0.094). In male carriers harboring DRB1*1101, the distribution of hepatitis B viral genotype was comparable between the two groups. HLA-DRB1*1101 correlates with less severe hepatitis in Taiwanese male carriers of hepatitis B virus.
Assuntos
Portador Sadio/fisiopatologia , Antígenos HLA-DR/genética , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/genética , Hepatite B Crônica/fisiopatologia , Índice de Gravidade de Doença , Adulto , Idoso , Alelos , Portador Sadio/virologia , Estudos de Coortes , Feminino , Genótipo , Antígenos HLA-DR/classificação , Antígenos HLA-DR/metabolismo , Cadeias HLA-DRB1 , Hepatite B Crônica/virologia , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , TaiwanRESUMO
Catechol-O-methyltransferase (COMT) is a methylation enzyme that catalyzes the degradation pathway and inactivation of dopamine. It is accepted widely as being involved in the modulation of dopaminergic physiology and prefrontal cortex (PFC) function. The COMT Val158Met polymorphism is associated with variation in COMT activity. COMT 158Met allele may be advantageous for PFC-related cognitive abilities; however, it is also associated with increased anxiety, depression, and emotional vulnerability in response to stress or educational adversity. We hypothesized that the COMT polymorphism might be associated with academic performance. In this study, 779 Taiwanese tenth-grade volunteers were recruited. Scores from the Basic Competency Test (BCT), an annual national competitive entrance examination, were used to evaluate academic performance. The results indicated that students bearing homozygous for the Met allele tended to perform more poorly in all BCT subtests as compared to the other groups. In particular, the former performed significantly more poorly in the science and social science subtests. These findings provide evidence that affective factors might overwhelm cognitive abilities in high-stake tests like the BCT.
Assuntos
Logro , Catecol O-Metiltransferase/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Alelos , Análise de Variância , Cognição/fisiologia , Feminino , Genótipo , Humanos , Masculino , Testes Neuropsicológicos , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND: Platelet CD36 is the receptor for oxidized low-density lipoprotein and collagen. The conventional platelet test cannot distinguish CD36-null subjects from normal expression subjects. Thromboelastography (TEG) testing can analyze global hemostasis. TEG testing data on CD36-null subjects are not available. METHODS: Our subjects were 40 apheresis platelet donors, including 8 CD36-null individuals. We grouped the donors according to the platelet CD36 expression levels to assess the effects of platelet CD36 expression levels on TEG measurement variables. RESULTS: The whole blood TEG test revealed that CD36-null subjects had prolonged reaction time of fibrin formation (TEG R time) and a slower rate to build up cross-linked fibrin (TEG α angle). The final maximal amplitudes of clot formation showed little difference between CD36-null individuals and normal expression individuals. Correlation analysis showed that CD36 expression levels were negatively correlated with TEG R time (râ¯=â¯-0.342, pâ¯=â¯0.031) and positively correlated with the TEG α angle (0.379, pâ¯=â¯0.016). TEG testing on apheresis platelet samples with diminished heterocellular interaction did not reveal differences between CD36-null and normal expression individuals. A subanalysis of the data of a group of healthy subjects showed that platelet CD36 levels correlated positively with platelet-monocyte aggregates (PMAs). Low PMA can diminish heterocellular interaction and likely explain the abnormal TEG results observed in CD36-null individuals. CONCLUSION: TEG distinguishes CD36-null subjects from normal CD36 expression subjects as having a slower rate of fibrin formation and reassessment of TEG-based diagnostic monitoring is necessary for CD36 null subjects.
Assuntos
Coagulação Sanguínea/genética , Antígenos CD36/metabolismo , Agregação Plaquetária/genética , Tromboelastografia/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Hepatitis C virus (HCV) infection is frequently associated with anti-SSA/Ro and anti-SSB/La autoantibodies. The objective of this study is to examine the prevalence of anti-SSA/Ro and anti-SSB/La autoantibodies in HCV-infected patients and their possible associations with HLA-DRB1 polymorphism in Chinese patients in Taiwan. About 288 HCV-infected patients were recruited for autoantibody detection and HLA-DRB1 typing. Anti-SSA/Ro and anti-SSB/La autoantibodies were detected in 12.8 and 9.7% of HCV-infected patients. Anti-SSA/Ro antibody was positively associated with age over 55 [p = 0.04; odds ratio = 2.17; 95% confidence interval (CI), 1.03-4.57]. Anti-SSB/La antibody was negatively associated with HLA-DR2 carriage (p = 0.024; odds ratio = 0.30; 95% CI, 0.10-0.90). No significant correlation was found between autoantibody production and gender, autoimmune manifestation, presence of cirrhosis, or hepatocellular carcinoma in HCV infection. In conclusion, anti-SSA/Ro and anti-SSB/La antibodies present frequently in HCV-infected patients. Anti-SSB/La antibody is negatively associated with HLA-DR2 in HCV-infected patients in Taiwan.
Assuntos
Anticorpos Antinucleares/imunologia , Antígeno HLA-DR2/genética , Antígeno HLA-DR2/imunologia , Hepatite C Crônica/imunologia , Adulto , Fatores Etários , Idoso , Anticorpos Antinucleares/genética , Especificidade de Anticorpos , Estudos de Coortes , Feminino , Hepatite C Crônica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , TaiwanRESUMO
Cabozantinib is an oral multikinase inhibitor that exhibits anti-tumor activity in several cancers. We found that cabozantinib was significantly cytotoxic to MV4-11 and Molm-13 cells that harbored FLT3-ITD, resulting in IC50 values of 2.4 nM and 2.0 nM, respectively. However, K562, OCI-AML3 and THP-1 (leukemia cell lines lacking FLT3-ITD) were resistant to cabozantinib, showing IC50 values in the micromolar range. Cabozantinib arrested MV4-11 cell growth at the G0/G1 phase within 24 h, which was associated with decreased phosphorylation of FLT3, STAT5, AKT and ERK. Additionally, cabozantinib induced MV4-11 cell apoptosis in a dose-dependent manner (as indicated by annexin V staining and high levels of cleaved caspase 3 and PARP-1), down-regulated the anti-apoptotic protein survivin and up-regulated the pro-apoptotic protein Bak. Thus, cabozantinib is selectively cytotoxic to leukemia cells with FLT3-ITD, causing cell-cycle arrest and apoptosis. In mouse xenograft model, cabozantinib significantly inhibited MV4-11 and Molm-13 tumor growth at a dosage of 10 mg/kg and showed longer survival rate. Clinical trials evaluating the efficacy of cabozantinib in acute myeloid leukemia (AML) with FLT3-ITD are warranted.
Assuntos
Anilidas/farmacologia , Antineoplásicos/farmacologia , Duplicação Gênica , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Predisposição Genética para Doença , Células HL-60 , Humanos , Células K562 , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Terapia de Alvo Molecular , Fenótipo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Carga Tumoral/efeitos dos fármacos , Células U937 , Ensaios Antitumorais Modelo de Xenoenxerto , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismoRESUMO
This exploratory study examines the relationship between cardiometabolic risk factors (blood pressure, waist circumference, BMI, and total cholesterol) and cognitive/academic performance. In this study, 1297 Taiwanese tenth-grade volunteers are recruited. Scores from the Basic Competency Test, an annual national competitive entrance examination, are used to evaluate academic performance. Cognitive abilities are accessed via the Multiple Aptitude Test Battery. The results indicate that systolic blood pressure is significantly, negatively associated with academic performance, both in male and female subjects. BMI and waist circumference are associated with verbal reasoning performance with an inverse U-shaped pattern, suggesting that both low and high BMI/waist circumference may be associated with lower verbal reasoning performance.
Assuntos
Doenças Cardiovasculares/fisiopatologia , Cognição/fisiologia , Aprendizagem/fisiologia , Adolescente , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/sangue , Colesterol/sangue , Feminino , Humanos , Insulina/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/fisiopatologia , Obesidade/sangue , Obesidade/fisiopatologia , Fatores de Risco , Taiwan , Triglicerídeos/sangue , Circunferência da CinturaRESUMO
Genetic alterations in the PI3K/AKT cascade have been linked to various human cancers including acute myeloid leukemia (AML) and have emerged to be promising targets for treatment. In this study, we explored the molecular mechanism and clinical implication of a specific allosteric AKT inhibitor, MK-2206, in the treatment of AML. Four leukemia cell lines, MV-4-11, MOLM-13, OCI/AML3, and U937, were used. Apoptosis and cell cycle distribution were determined by flow cytometry analysis. Expression of anti-apoptotic protein family and glycogen synthase kinase 3ß (GSK3ß) signaling was determined by western blotting. Drug combination effects of MK-2206 with cytarabine were evaluated by cell proliferation assay, and the combination index values were calculated by CompuSyn software. MK-2206 had no effect on normal peripheral blood mononuclear cells, but induced G1-phase arrest and apoptosis in leukemia cells. Among anti-apoptotic Bcl-2 family members, only myeloid cell leukemia-1 (Mcl-1) was significantly suppressed. Mcl-1 suppression by MK-2206 was closely associated with decreased GSK3ß phosphorylation at Ser9, an event leads to GSK3ß activation. Furthermore, the effect of MK-2206 on Mcl-1 downregulation was abolished by GSK3ß inhibitor, lithium chloride and proteasome inhibitor, MG-132, suggesting that MK-2206 acted through a GSK3ß-mediated, proteasome-dependent protein degradation. In addition, co-administration of MK-2206 with cytarabine could enhance the cytotoxic efficacy of cytarabine in leukemia cell lines. In conclusion, we have demonstrated that MK-2206 is an active agent in AML and its efficacy as in combination with cytarabine is implicated.
Assuntos
Apoptose/efeitos dos fármacos , Citarabina/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Fase G1/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células U937RESUMO
Childhood acute lymphoblastic leukemia (ALL) with t(12;21), which results in expression of the ETV6/RUNX1 fusion gene, is the most common chromosomal lesion in precursor-B (pre-B) ALL. We identified 17 microRNAs that were downregulated in ETV6/RUNX1+ compared with ETV6/RUNX1- clinical samples. Among these microRNAs, miR-181a-1 was the most significantly reduced (by ~75%; P < 0.001). Using chromatin immunoprecipitation, we demonstrated that ETV6/RUNX1 directly binds the regulatory region of MIR181A1, and knockdown of ETV6/RUNX1 increased miR-181a-1 level. We further showed that miR-181a (functional counterpart of miR-181a-1) could target ETV6/RUNX1 and cause a reduction in the level of the oncoprotein ETV6/RUNX1, cell growth arrest, an increase in apoptosis, and induction of cell differentiation in ETV6/RUNX1+ cell line. Moreover, ectopic expression of miR-181a also resulted in decreased CD10 hyperexpression in ETV6/RUNX1+ primary patient samples. Taken together, our results demonstrate that MIR181A1 and ETV6/RUNX1 regulate each other, and we propose that a double negative loop involving MIR181A1 and ETV6/RUNX1 may contribute to ETV6/RUNX1-driven arrest of differentiation in pre-B ALL.
Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , MicroRNAs/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Repressoras/genética , Translocação Genética/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Subunidade alfa 2 de Fator de Ligação ao Core/biossíntese , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Regulação Leucêmica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , MicroRNAs/biossíntese , MicroRNAs/metabolismo , Proteínas de Fusão Oncogênica/biossíntese , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas Proto-Oncogênicas c-ets/biossíntese , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Repressoras/biossíntese , Proteínas Repressoras/metabolismo , Variante 6 da Proteína do Fator de Translocação ETSRESUMO
BACKGROUND: In pig-to-human discordant xenotransplantation, the xenograft can be rejected by a formidable human xenogenic T-cell response, even if the graft has gone through hyperacute rejection or delayed xenograft rejection (acute vascular rejection). We therefore examined, in this study, whether the human-to-pig cellular response could be attenuated through the generation of a transgenic pig for human HLA II. METHODS: With the technique of microinjection, we produced the HLA DPw0401 transgenic pig. The expression of the HLA DPw0401 gene on peripheral blood mononuclear cells (PBMCs) of the transgenic pig was examined by reverse transcriptase-polymerase chain reaction and flow cytometry. The antigenicity of the transgenic HLA DPw0401 molecule was tested by the HLA DPw0401-primed lymphocyte test reagent. The cellular response was analyzed by xenogenic mixed lymphocyte culture. RESULTS: The mRNA and protein of HLA DPw0401 were expressed in the PBMCs of the transgenic pig. The PBMCs of the HLA transgenic pig induced a stronger cellular reaction to HLA DPw0401-primed lymphocyte test reagents than the nontransgenic littermate pig (n=7, P<0.01). In direct xenogenic mixed lymphocyte culture with responders from HLA DPw0401(+) humans, the PBMCs from the HLA DPw0401 transgenic pig, as compared with those from the normal pig, induced a lower degree of xenogenic cellular response to human PBMCs (n=4, P=0.08). CONCLUSIONS: Our preliminary data demonstrated the possibility that the human HLA DPw0401 phenotype can be transferred onto porcine cells through the generation of HLA transgenic pigs and make the PBMCs of humans more tolerant to porcine cells.
Assuntos
Antígenos HLA-DP/genética , Linfócitos T/imunologia , Transplante Heterólogo/imunologia , Animais , Animais Geneticamente Modificados , Humanos , Teste de Cultura Mista de Linfócitos , RNA Mensageiro/análise , SuínosRESUMO
Previous serotyping in Chinese patients has failed to confirm an association between HLA-Cw6 and psoriasis. As serotyping has proved to be less valuable in the determination of HLA-C, genotyping of HLA-C in 68 Taiwanese psoriasis vulgaris (PSV) patients was performed using polymerase chain reaction/sequence-specific oligonucleotide probe hybridization (PCR-SSOPH) of HLA-Cw genes. Compared to 213 non-PSV control subjects, HLA-Cw6 was significantly associated with PSV (16.18% of PSV patients vs 5.16% of controls; odds ratio 3.53, Pc=10(-4)). The amino acid residues on the heavy chain of the HLA-Cw antigens from exon one to exon five were also analyzed. Asp 9, Ser 24, Ala 73, Asp 90, Trp 97, Trp 156 and Asn 77/Lys 80 were found to be positively associated with PSV ( Pc=0.0044, 0.0008, 0.0026, 0.0014, 0.039, 0.0020 and 0.0000, respectively).