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1.
Cancer Gene Ther ; 30(8): 1105-1113, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37041276

RESUMO

Members of the HDAC family are predictive biomarkers and regulate the tumorigenesis in several cancers. However, the role of these genes in the biology of intracranial ependymomas (EPNs) remains unexplored. Here, an analysis of eighteen HDACs genes in an EPN transcriptomic dataset, revealed significantly higher levels of HDAC4 in supratentorial ZFTA fusion (ST-ZFTA) compared with ST-YAP1 fusion and posterior fossa EPNs, while HDAC7 and SIRT2 were downregulated in ST-ZFTA. HDAC4 was also overexpressed in ST-ZFTA as measured by single-cell RNA-Seq, quantitative real time-polymerase chain reaction, and immunohistochemistry. Survival analyses showed a significantly worse outcome for EPNs with higher HDAC4 and SIRT1 mRNA levels. Ontology enrichment analysis showed an HDAC4-high signature consistent with viral processes while collagen-containing extracellular matrix and cell-cell junction were enriched in those with an HDAC4-low signature. Immune gene analysis demonstrated a correlation between HDAC4 expression and low levels of NK resting cells. Several small molecules compounds targeting HDAC4 and ABCG2, were predicted by in silico analysis to be effective against HDAC4-high ZFTA. Our results provide novel insights into the biology of the HDAC family in intracranial ependymomas and reveal HDAC4 as a prognostic marker and potential therapeutic target in ST-ZFTA.


Assuntos
Neoplasias Encefálicas , Ependimoma , Humanos , Prognóstico , Fatores de Transcrição/genética , Ependimoma/genética , Ependimoma/metabolismo , Neoplasias Encefálicas/genética , Perfilação da Expressão Gênica , Histona Desacetilases/genética , Proteínas Repressoras/genética
2.
Biochem Pharmacol ; 182: 114230, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32979352

RESUMO

L-asparaginase (ASNase) from Escherichia coli (EcAII) is used in the treatment of acute lymphoblastic leukaemia (ALL). EcAII activity in vivo has been described to be influenced by the human lysosomal proteases asparaginyl endopeptidase (AEP) and cathepsin B (CTSB); these hydrolases cleave and could expose epitopes associated with the immune response against EcAII. In this work, we show that ASNase resistance to CTSB and/or AEP influences the formation of anti-ASNase antibodies, one of the main causes of hypersensitivity reactions in patients. Error-prone polymerase chain reaction was used to produce variants of EcAII more resistant to proteolytic cleavage by AEP and CTSB. The variants with enzymatic activity and cytotoxicity levels equivalent to or better than EcAII WT were submitted to in vivo assays. Only one of the mutants presented increased serum half-life, so resistance to these proteases is not the only feature involved in EcAII stability in vivo. Our results showed alteration of the phenotypic profile of B cells isolated after animal treatment with different protease-resistant proteoforms. Furthermore, mice that were exposed to the protease-resistant proteoforms presented lower anti-asparaginase antibodies production in vivo. Our data suggest that modulating resistance to lysosomal proteases can result in less immunogenic protein drugs.


Assuntos
Antineoplásicos/farmacologia , Asparaginase/farmacologia , Produtos Biológicos/farmacologia , Fenômenos Imunogenéticos/efeitos dos fármacos , Lisossomos/imunologia , Peptídeo Hidrolases/farmacologia , Sequência de Aminoácidos , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Asparaginase/química , Asparaginase/uso terapêutico , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Galinhas , Relação Dose-Resposta a Droga , Escherichia coli , Feminino , Cavalos , Humanos , Fenômenos Imunogenéticos/fisiologia , Células Jurkat , Lisossomos/química , Camundongos , Camundongos Endogâmicos BALB C , Peptídeo Hidrolases/química , Peptídeo Hidrolases/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Estrutura Secundária de Proteína
3.
Mol Genet Genomic Med ; 8(9): e1168, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32592449

RESUMO

BACKGROUND: The p.Arg337His mutation of the TP53 is the most frequent germline missense variant associated with cancer described so far in this gene. It is mainly found in the South and Southeastern regions of Brazil, where it has been associated with a high incidence of pediatric adrenocortical (ACT) and choroid plexus tumors. The frequency and geographic distribution of this mutation is largely unknown, except for the Parana State, where a mean prevalence of 0.27% was reported. In the present study, we developed a high-throughput method for p.Arg337His genotyping, what allowed us to determine the frequency and geographic distribution of this mutation in a cohort from the most populous state in Brazil. METHODS: Consecutive samples from 31,612 newborns from São Paulo State were screened for p.Arg337His. The allelic discrimination was done by real-time polymerase chain reaction (PCR) and the presence of haplotype A3 in carriers was examined by using allele-specific oligonucleotide PCR, followed by nested-PCR to detect the SNP rs9894946. RESULTS: We found 67 (0.21%) samples positive for this mutation. The highest p.Arg337His frequencies were found in the cities close to the boundary between São Paulo and Minas Gerais State. No association could be found between p.Arg337His and gender, ethnicity, premature birth or twinning. Remarkably, a trend was found between the geographic distribution of p.Arg337His carriers and occurrence of ACT. CONCLUSION: We presented for the first time the p.Arg337His frequency among individuals unselected for any disease from a subset of the São Paulo State, the most populous in Brazil. The allele discrimination assay we presented here has proven to be a reliable and efficient method for high-throughput genotyping. ACT was found to be a good sentinel cancer to suppose p.Arg337His presence in our region.


Assuntos
Neoplasias do Córtex Suprarrenal/epidemiologia , Frequência do Gene , Mutação de Sentido Incorreto , População/genética , Proteína Supressora de Tumor p53/genética , Neoplasias do Córtex Suprarrenal/genética , Brasil , Feminino , Técnicas de Genotipagem/métodos , Humanos , Masculino , Prevalência
5.
Anticancer Drugs ; 30(8): 828-837, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30932944

RESUMO

Acute leukemias are a heterogeneous group of aggressive malignant neoplasms associated with severe morbidities due to the nonselectivity of current chemotherapeutic drugs to nonmalignant cells. The investigation of novel natural and synthetic structures that might be used for the development of new drugs with greater efficiency and selectivity to leukemic cells is mandatory. In this context, thiosemicarbazones have been well described in the literature by their several biological properties and their reaction is known as versatile, low-cost, and highly chemoselective. With this perspective, this study aimed to investigate the cytotoxic effect and the main death mechanisms of a novel thiosemicarbazone (LAP17) on acute leukemia cell lines K562 and Jurkat. The results show that the strong cytotoxic effect of LAP17 to leukemic cells is due to apoptosis induction, which resulted in caspase-3 activation and DNA fragmentation. Intrinsic apoptosis seems to be related to the inversion of Bax/Bcl-2 expression, ΔΨm loss, and AIF release, whereas extrinsic apoptosis was initiated by FasR. Gene-expression profiling of HL-60 cells treated with LAP17 by the microarray technique revealed a significant enrichment of gene sets related to cell cycle arrest at G2/M. Accordingly, K562 and Jurkat cells treated with LAP17 revealed a clear arrest at G2/M phase. Taking into consideration that LAP17 was not cytotoxic to nonhematological cells (peripheral blood mononuclear cell and erythrocytes), these results suggest that LAP17 is a promising new compound that might be used as a prototype for the development of new antileukemic agents.


Assuntos
Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucócitos Mononucleares/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Tiossemicarbazonas/química , Antineoplásicos/química , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ciclo Celular , Proliferação de Células , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Potencial da Membrana Mitocondrial , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Células Tumorais Cultivadas
6.
Nat Prod Res ; 33(11): 1633-1636, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29338345

RESUMO

Anacardium occidentale leaves are used in folk medicine due its therapeutic properties attributed to phenolic compounds. Therefore, this study was undertaken on its hydroethanolic leaf extract (AoHE) to evaluate cytotoxicity and apoptosis induction on acute lymphoblastic leukaemia cells. Results indicated that AoHE interfered in the cell cycle progression, inducing apoptosis by activation of casp3 at lower concentrations, thence, a promising candidate for the development of new cancer drugs.


Assuntos
Anacardium/química , Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Apoptose/efeitos dos fármacos , Caspase 3/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Fenóis/análise , Folhas de Planta/química , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia
7.
AMB Express ; 8(1): 178, 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30382415

RESUMO

The glycoprotein APA (Alanine- and Proline-rich Antigen, a 45/47 kDa antigen complex, Rv1860) is considered as a major immunodominant antigen secreted by M. tuberculosis. This antigen has proved to be highly immunogenic in experimental models and humans, presenting a significant potential for further development of a new vaccine for tuberculosis. Glycosylation plays a key role in the immunogenicity of the APA protein. Because plants are known to promote post-translational modification such as glycosylation and to be one of the most economic and safe hosts for recombinant protein expression, we have over expressed the APA protein in transgenic tobacco plants aiming to produce a glycosylated version of the protein. Seeds are known to be a well-suited organ to accumulate recombinant proteins, due to low protease activity and higher protein stability. We used a seed-specific promoter from sorghum, a signal peptide to target the protein to the endoplasmic reticulum and ultimately in the protein storage vacuoles. We show that the recombinant protein accumulated in the seeds had similar isoelectric point and molecular weight compared with the native protein. These findings demonstrate the ability of tobacco plants to produce glycosylated APA protein, opening the way for the development of secure, effective and versatile vaccines or therapeutic proteins against tuberculosis.

8.
J. pediatr. (Rio J.) ; 94(4): 432-439, July-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-954624

RESUMO

Abstract Objective: To evaluate the clinical features associated with adrenocortical hormone overexpression and familial cancer profiling as potential markers for early detection of adrenocortical tumors in children from South and Southeast Brazil. Methods: The clinical manifestations and anthropometric measurements of 103 children diagnosed with adrenocortical tumors were analyzed. Results: Between 1982 and 2011, 69 girls and 34 boys diagnosed with adrenocortical tumors were followed-up for a median time of 9.0 years (0-34 years). Signs of androgen overproduction alone (n = 75) or associated with cortisol (n = 18) were present in 90.3%. TP53 p.R337H mutation was found in 90.5% of patients. Stages I, II, III, and IV were observed in 45.6%, 27.2%, 19.4%, and 7.8% of patients, respectively. At diagnosis, there were no significant differences in height (p = 0.92) and weight (p = 0.22) among children with adrenocortical tumors, but children with virilization alone had significantly higher height-for-age Z-scores (0.92 ± 1.4) than children with hypercortisolism alone or combined (−0.32 ± 1,8; p = 0.03). The five-year overall survival was 76.7% (SD ± 4.2). Patients with advanced-stage disease had a significantly worse prognosis than those with limited disease (p < 0.001). During follow-up, ten of 55 p.R337H carrier parents developed cancer, whereas none of the 55 non-carriers did. Conclusions: Signs of adrenocortical hormone overproduction appear early, even in cases with early-stage. These signs can be identified at the physical examination and anthropometric measurements. In southern Brazil, pediatric adrenocortical tumor is a sentinel cancer for detecting families with germline p.R337H mutation in TP53 gene.


Resumo Objetivo: Avaliar as manifestações clínicas da hiperexpressão de hormônios do córtex da adrenal e câncer familiar como marcadores para a detecção precoce de tumores adrenocorticais em crianças do Sul e Sudeste do Brasil. Pacientes e métodos: Foram analisadas as manifestações clínicas e antropométricas de 103 crianças diagnosticadas com tumores adrenocorticais. Resultados: Entre 1982 e 2011, 69 meninas e 34 meninos diagnosticados com tumores adrenocorticais foram acompanhados por um tempo mediano de nove anos (0-34). Ao diagnóstico, sinais de virilização isolada (n = 75) ou associada ao cortisol (n = 18) estavam presentes em 90,3% dos pacientes; a mutação do gene TP53 p.R337H foi identificada em 90,5% dos pacientes. Os pacientes foram classificados em estádio I (45,6%), II (27,2%), III (19,4%) e IV (7,8%). Ao diagnóstico, não houve diferença significativa para as medidas de altura (p = 0,92) e de peso (p = 0,22) entre as crianças com tumores adrenocorticais, mas crianças com virilização tiveram escore-Z mais elevado para a idade (0,92 ± 1,4) do que aquelas com hipercortisolismo isolado ou combinado (−0,32 ± 1,8; p = 0,03). A sobrevida global de cinco anos foi de 76,7% (DP ± 4,2). Pacientes com estádios avançados tiveram pior prognóstico (p < 0,001). Durante o seguimento, 10 dos 55 genitores portadores da p.R337H desenvolveram câncer, enquanto que nenhum caso ocorreu entre os 55 não portadores. Conclusões: Os sinais de hiperprodução de hormônios adrenocorticais aparecem precocemente no desenvolvimento do tumor e podem ser identificados pelo exame físico e pelas medidas antropométricas na consulta pediátrica de rotina. O tumor adrenocortical pediátrico é sentinela para a detecção de câncer em famílias que segregam a mutação germinativa p.R337H do gene TP53.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Genes p53/genética , Proteína Supressora de Tumor p53/genética , Neoplasias do Córtex Suprarrenal/diagnóstico , Neoplasias do Córtex Suprarrenal/genética , Mutação em Linhagem Germinativa/genética , Predisposição Genética para Doença/genética , Linhagem , Estudos Longitudinais , Estadiamento de Neoplasias
9.
J Pediatr (Rio J) ; 94(4): 432-439, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28864397

RESUMO

OBJECTIVE: To evaluate the clinical features associated with adrenocortical hormone overexpression and familial cancer profiling as potential markers for early detection of adrenocortical tumors in children from South and Southeast Brazil. METHODS: The clinical manifestations and anthropometric measurements of 103 children diagnosed with adrenocortical tumors were analyzed. RESULTS: Between 1982 and 2011, 69 girls and 34 boys diagnosed with adrenocortical tumors were followed-up for a median time of 9.0 years (0-34 years). Signs of androgen overproduction alone (n=75) or associated with cortisol (n=18) were present in 90.3%. TP53 p.R337H mutation was found in 90.5% of patients. Stages I, II, III, and IV were observed in 45.6%, 27.2%, 19.4%, and 7.8% of patients, respectively. At diagnosis, there were no significant differences in height (p=0.92) and weight (p=0.22) among children with adrenocortical tumors, but children with virilization alone had significantly higher height-for-age Z-scores (0.92±1.4) than children with hypercortisolism alone or combined (-0.32±1,8; p=0.03). The five-year overall survival was 76.7% (SD±4.2). Patients with advanced-stage disease had a significantly worse prognosis than those with limited disease (p<0.001). During follow-up, ten of 55 p.R337H carrier parents developed cancer, whereas none of the 55 non-carriers did. CONCLUSIONS: Signs of adrenocortical hormone overproduction appear early, even in cases with early-stage. These signs can be identified at the physical examination and anthropometric measurements. In southern Brazil, pediatric adrenocortical tumor is a sentinel cancer for detecting families with germline p.R337H mutation in TP53 gene.


Assuntos
Neoplasias do Córtex Suprarrenal/diagnóstico , Neoplasias do Córtex Suprarrenal/genética , Genes p53/genética , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa/genética , Proteína Supressora de Tumor p53/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Estadiamento de Neoplasias , Linhagem
10.
Cancer ; 123(16): 3150-3158, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28387921

RESUMO

BACKGROUND: The tumor protein p53 (TP53) arginine-to-histidine mutation at codon 337 (R337H) predisposes children to adrenocortical tumors (ACTs) and, rarely, to other childhood tumors, but its impact on adult cancer remains undetermined. The objective of this study was to investigate the frequency and types of cancer in relatives of children with ACT who carry the TP53 R337H mutation. METHODS: TP53 R337H testing was offered to relatives of probands with ACT. The parental lineage segregating the R337H mutation was identified in all families. The frequency and distribution of cancer types were compared according to R337H status. The authors' data also were compared with those publicly available for children with TP53 mutations other than R337H. RESULTS: The mean and median follow-up times for the probands with ACT were 11.2 years and 9.7 years (range, 3-32 years), respectively. During this time, cancer was diagnosed in 12 of 81 first-degree relatives (14.8%) carrying the R337H mutation but in only 1 of 94 noncarriers (1.1%; P = .0022). At age 45 years, the cumulative risk of cancer was 21% (95% confidence interval, 5%-33%) in carriers and 2% (95% confidence interval, 0%-4%) in noncarriers (P = .008). The frequency of cancer was higher in the R337H segregating lineages than in the nonsegregating lineages (249 of 1410 vs 66 of 984 individuals; P < .001). Breast and gastric cancer were the most common types. CONCLUSIONS: TP53 R337H carriers have a lifelong predisposition to cancer with a bimodal age distribution: 1 peak, represented by ACT, occurs in the first decade of life, and another peak of diverse cancer types occurs in the fifth decade. The current findings have implications for genetic counseling and surveillance of R337H carriers. Cancer 2017;123:3150-58. © 2017 American Cancer Society.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Neoplasias da Mama/genética , Neoplasias Gástricas/genética , Proteína Supressora de Tumor p53/genética , Adolescente , Adulto , Brasil , Criança , Pré-Escolar , Família , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Adulto Jovem
11.
Biochim Biophys Acta Mol Basis Dis ; 1863(1): 121-128, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27615426

RESUMO

Lysine is catabolized in mammals through the saccharopine and pipecolate pathways - the former is mainly hepatic and renal, and the latter is believed to play a role in the cerebral lysine oxidation. Both pathways lead to the formation of aminoadipic semialdehyde (AASA) that is then oxidized to aminoadipate (AAA) by antiquitin (ALDH7A1). Mutations in the ALDH7A1 gene result in the accumulation of AASA and its cyclic form, piperideine-6-carboxylate (P6C), which causes pyridoxine-dependent epilepsy (PDE). P6C reacts with pyridoxal 5'-phosphate (PLP) causing its inactivation. Here, we used liquid chromatography-mass spectrometry to investigate lysine catabolism in mice injected with lysine labelled at either its nitrogen epsilon (ε-15N) or nitrogen alpha (α-15N). Analysis of ε-15N and α-15N lysine catabolites in plasma, liver and brain suggested the saccharopine as the main pathway for AAA biosynthesis. Although there was evidence for upstream cerebral pipecolate pathway activity, the resulting pipecolate does not appear to be further oxidized into AASA/P6C/AAA. By far the bulk of lysine degradation and therefore, the primary source of lysine catabolites are hepatic and renal. The results indicate that the saccharopine pathway is primarily responsible for body's production of AASA/P6C. The centrality of the saccharopine pathway in whole body lysine catabolism opens new possibilities of therapeutic targets for PDE. We suggest that inhibition of this pathway upstream of AASA/P6C synthesis may be used to prevent its accumulation benefiting PDE patients. Inhibition of the enzyme aminoadipic semialdehyde synthase, for example, could constitute a new strategy to treat PDE and other inherited diseases of lysine catabolism.


Assuntos
Ácido 2-Aminoadípico/metabolismo , Epilepsia/metabolismo , Lisina/análogos & derivados , Lisina/metabolismo , Redes e Vias Metabólicas , Ácido 2-Aminoadípico/análogos & derivados , Animais , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Ácidos Picolínicos/metabolismo , Fosfato de Piridoxal/metabolismo
12.
Oncotarget ; 7(51): 84634-84644, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27705928

RESUMO

BACKGROUND: Overexpression of the oncogene yes-associated-protein-1 (YAP1) is associated with increased cell proliferation in human cancers. YAP1 is a potential target of the Wnt/beta-catenin pathway, which plays an important role in adrenocortical tumors (ACT). The role of YAP1 in adrenocortical tumorigenesis has not been assessed. AIMS: To evaluate YAP1 expression in normal adrenals and pediatric ACT and its association with disease outcome. To investigate the interaction between YAP1 and the Wnt/beta-catenin pathway in adrenocortical cells. RESULTS: Strong YAP1 staining was present in fetal adrenals and pediatric ACT but weak in postnatal adrenals. In pediatric ACT, YAP1 mRNA overexpression was associated with death, recurrent/metastatic disease and lower overall survival. The inhibition of the Wnt/beta-catenin pathway increased YAP1 mRNA expression. siYAP1 increased CTNNB1/beta-catenin expression and nuclear staining regardless of DLV2, moreover, it decreased cell growth and impaired cell migration. MATERIALS AND METHODS: We assessed in 42 pediatric ACT samples the YAP1 protein expression by immunohistochemistry and mRNA expression by RT-qPCR and analyzed their association with outcome. As controls, we resort 32 fetal and postnatal normal adrenals for IHC and 10 normal adrenal cortices for RT-qPCR. The interaction between YAP1 and the Wnt/beta-catenin pathway was assessed in NCI-H295 adrenocortical cells by inhibiting the TCF/beta-catenin complex and by knocking down YAP1. CONCLUSION: YAP1 overexpression is a marker of poor prognosis for pediatric patients with ACT. In adrenocortical cells, there is a close crosstalk between YAP1 and Wnt/beta-catenin. These data open the possibility of future molecular therapies targeting Hippo/YAP1 signaling to treat advanced ACT.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias do Córtex Suprarrenal/metabolismo , Córtex Suprarrenal/metabolismo , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adolescente , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/mortalidade , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células , Criança , Pré-Escolar , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Lactente , Masculino , Metástase Neoplásica , Recidiva Local de Neoplasia , Fosfoproteínas/genética , Transdução de Sinais , Análise de Sobrevida , Fatores de Transcrição , Proteínas Wnt/metabolismo , Proteínas de Sinalização YAP , beta Catenina/metabolismo
13.
Springerplus ; 5: 172, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27026869

RESUMO

Detection and quantification of lysine degradation metabolites in plasma is necessary for the diagnosis and follow-up of diseases such as pyridoxine-dependent epilepsy. The principal metabolites involved in the disease are related to the first steps of lysine oxidation, either through the saccharopine or the pipecolate pathways. Currently, there are three different analytical methods used to assess the content of these metabolites in urine and plasma, but they require different sample preparations and analytical equipment. Here, we describe a protocol that calls for a simple sample preparation and uses liquid chromatography tandem mass spectrometry (LC-MS/MS) that allows simultaneous detection and quantification of underivatized l-saccharopine, l-aminoadipic acid, l-pipecolic acid, piperideine-6-carboxylate, l-glutamic acid, and pyridoxal-5-phosphate in plasma samples. To validate the method we analyzed the time course degradation after intraperitoneal injection of l-lysine in C57BL/6/J mice. We observed that the degradation of lysine through the saccharopine pathway reached a maximum within the first 2 h. At this time point there was an increase in the levels of the metabolites saccharopine, aminoadipic acid, and pipecolic acid by 3-, 24- and 3.4-fold, respectively, compared to time zero levels. These metabolites returned to basal levels after 4-6 h. In conclusion, we have developed a LC-MS/MS approach, which allows simultaneous analysis of lysine degradation metabolites without the need for derivatization.

14.
Eur J Med Chem ; 96: 504-18, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25951294

RESUMO

Tubulin-interacting agents, like vinca alkaloid and taxanes, play a fundamental role in cancer chemotherapy, making cellular microtubules (MT), one of the few validated anticancer targets. Cancer resistance to classical MT inhibitors has motivated the development of novel molecules with increased efficacy and lower toxicity. Aiming at designing structurally-simple inhibitors of MT assembly, we synthesized a series of thirty-one 3,4,5-trimethoxy-hydrazones and twenty-five derivatives or analogs. Docking simulations suggested that a representative N-acylhydrazone could adopt an appropriate stereochemistry inside the colchicine-binding domain of tubulin. Several of these compounds showed anti-leukemia effects in the nanomolar concentration range. Interference with MT polymerization was validated by the compounds' ability to inhibit MT assembly at the biochemical and cellular level. Selective toxicity investigations done with the most potent compound, a 3,4,5-trimethoxy-hydrazone with a 1-naphthyl group, showed remarkably selective toxicity against leukemia cells in comparison with stimulated normal lymphocytes, and no acute toxicity in vivo. Finally, this molecule was as active as vincristine in a murine model of human acute lymphoblastic leukemia at a weekly dose of 1 mg/kg.


Assuntos
Anisóis/farmacologia , Antineoplásicos/farmacologia , Hidrazonas/farmacologia , Microtúbulos/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Animais , Anisóis/síntese química , Anisóis/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Microtúbulos/metabolismo , Modelos Moleculares , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas
15.
Pediatr Blood Cancer ; 61(11): 1940-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25156210

RESUMO

BACKGROUND: Low expression of HLA class II antigens has been associated with more aggressive disease in several human malignancies including adult adrenocortical tumors (ACT), but their clinical relevance in pediatric ACT needs to be investigated. PROCEDURE: This study analyzed the expression profile of three class II histocompatibility genes (HLA-DRA, HLA-DPA1, and HLA-DPB1) in 58 consecutive pediatric ACT (13 adenomas and 45 carcinomas) by quantitative real time PCR and their association with clinical and biological features. HLA-DPA1 protein level was determined by immunohistochemistry. RESULTS: A significant association (P < 0.01) was observed between lower expression levels of the three genes analyzed and poor prognostic factors such as age ≥ 4 years, tumor size ≥ 200 cm(3), tumor weight ≥ 100 g, and metastatic disease; the presence of an unfavorable event and death. Underexpression of the HLA-DRA, HLA-DPA1, and HLA-DPB1 genes were associated with lower 5-year event-free survival (EFS) (P = 0.017, P < 0.001, and P = 0.017, respectively). Cox multivariate analysis showed that HLA-DPA1 was an independent prognostic factor (P = 0.029) when analyzed in association with stage IV, age and tumor size. Significantly lower EFS was also observed in patients with negative/weak immunostaining for HLA-DPA1 (P = 0.002). Similar results were observed when only patients classified as having carcinomas were analyzed. CONCLUSION: Our results suggest that lower expression of HLA-DRA, HLA-DPA1, and HLA-DPB1 genes may contribute to more aggressive disease in pediatric ACT. HLA-DPA1 immunostaining may represent potential aggressiveness marker in this tumor.


Assuntos
Neoplasias do Córtex Suprarrenal/imunologia , Cadeias alfa de HLA-DP/genética , Cadeias beta de HLA-DP/genética , Cadeias alfa de HLA-DR/genética , Adolescente , Neoplasias do Córtex Suprarrenal/mortalidade , Neoplasias do Córtex Suprarrenal/patologia , Criança , Pré-Escolar , Feminino , Cadeias alfa de HLA-DP/análise , Cadeias beta de HLA-DP/análise , Cadeias alfa de HLA-DR/análise , Humanos , Lactente , Masculino , Prognóstico
16.
J Clin Endocrinol Metab ; 99(7): E1209-16, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24712566

RESUMO

BACKGROUND: The sonic hedgehog (SHH) pathway plays a key role in rodent adrenal cortex development and is involved in tumorigenesis in several human tissues, but data in human adrenal glands are limited. OBJECTIVES: The objectives of the study were to analyze the involvement of the SHH pathway in human adrenal development and tumorigenesis and the effects of SHH inhibition on an adrenocortical tumor (ACT) cell line. PATIENTS AND METHODS: Expression of SHH pathway components was evaluated by immunohistochemistry in 51 normal adrenals (33 fetal) and 34 ACTs (23 pediatric) and by quantitative PCR in 81 ACTs (61 pediatric) and 19 controls (10 pediatric). The effects of SHH pathway inhibition on gene expression and cell viability in the NCI-H295A adrenocortical tumor cell line after cyclopamine treatment were analyzed. RESULTS: SHH pathway proteins were present in fetal and postnatal normal adrenals and showed distinct patterns of spatiotemporal expression throughout development. Adult adrenocortical carcinomas presented with higher expression of PTCH1, SMO, GLI3, and SUFU compared with normal adult adrenal cortices. Conversely, pediatric ACTs showed lower mRNA expression of SHH, PTCH1, SMO, GLI1, and GLI3 compared with normal pediatric adrenal cortices. In vitro treatment with cyclopamine resulted in decreased GLI3, SFRP1, and CTNNB1 mRNA expression and ß-catenin staining as well as decreased cell viability. CONCLUSIONS: The SHH pathway is active in human fetal and postnatal adrenals, up-regulated in adult adrenocortical carcinomas, and down-regulated in pediatric ACTs. SHH pathway antagonism impaired cell viability. The SHH pathway is deregulated in ACTs and might provide a new target therapy to be explored.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Córtex Suprarrenal/embriologia , Córtex Suprarrenal/crescimento & desenvolvimento , Carcinoma Adrenocortical/genética , Proteínas Hedgehog/genética , Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/metabolismo , Adulto , Estudos de Casos e Controles , Células Cultivadas , Criança , Desenvolvimento Embrionário/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas Hedgehog/metabolismo , Humanos , Recém-Nascido , Gravidez , Estudos Retrospectivos , Transdução de Sinais/genética
17.
Clin Endocrinol (Oxf) ; 81(4): 503-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24717047

RESUMO

CONTEXT: The role of planar cell polarity (Wnt/PCP) and calcium-dependent (Wnt/Ca) noncanonical Wnt pathways in adrenocortical tumours (ACTs) is unknown. OBJECTIVES: To investigate the gene expression of Wnt/PCP and Wnt/Ca pathways and its association with TP53 p.R337H and CTNNB1 mutations in paediatric and adult ACTs and to correlate these findings with clinical outcome. PATIENTS: Expression of noncanonical Wnt-related genes was evaluated in 91 ACTs (66 children and 25 adults) by qPCR and the expression of beta-catenin, P53 and protein effectors of Wnt/Ca (NFAT) and Wnt/PCP (JNK) by immunohistochemistry. TP53 and CTNNB1 genes were sequenced. RESULTS: TP53 p.R337H mutation frequency was higher in children (86% vs 28%), while CTNNB1 mutation was higher in adults (32% vs 6%). Mortality was higher in adults harbouring TP53 p.R337H and in children with CTNNB1 mutations. Overexpression of WNT5A, Wnt/Ca ligand, was observed in children and adults. Overexpression of MAPK8 and underexpression of PRICKLE, Wnt/PCP mediators, were observed in paediatric but not in adult cases. Cytoplasmic/nuclear beta-catenin and P53 accumulation was observed in the majority of paediatric and adult ACTs as well as NFAT and JNK. Overexpression of MAPK8 and underexpression of PRICKLE were associated with mortality in children, while overexpression of WNT5A and underexpression of PRICKLE were associated with mortality in adults. CONCLUSIONS: In our study, TP53 p.R337H and CTNNB1 mutations correlated with poor prognosis in adults and children, respectively. We demonstrate, for the first time, the activation of Wnt/PCP and Wnt/Ca noncanonical pathway genes, and their association with poor outcome in children and adults, suggesting their putative involvement in ACTs aggressiveness.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Via de Sinalização Wnt/fisiologia , Adolescente , Neoplasias do Córtex Suprarrenal/genética , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Via de Sinalização Wnt/genética , Adulto Jovem , beta Catenina/genética , beta Catenina/metabolismo
18.
Eur J Med Chem ; 63: 501-10, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23524161

RESUMO

Based on classical colchicine site ligands and a computational model of the colchicine binding site on beta tubulin, two classes of chalcone derivatives were designed, synthesized and evaluated for inhibition of tubulin assembly and toxicity in human cancer cell lines. Docking studies suggested that the chalcone scaffold could fit the colchicine site on tubulin in an orientation similar to that of the natural product. In particular, a 3,4,5-trimethoxyphenyl ring adjacent to the carbonyl group appeared to benefit the ligand-tubulin interaction, occupying the same subcavity as the corresponding moiety in colchicine. Consistent with modeling predictions, several 3,4,5-trimethoxychalcones showed improved cytotoxicity to murine acute lymphoblastic leukemia cells compared with a previously described parent compound, and inhibited tubulin assembly in vitro as potently as colchicine. The most potent chalcones inhibited the growth of human leukemia cell lines at nanomolar concentrations, caused microtubule destabilization and mitotic arrest in human cervical cancer cells, and inhibited human breast cancer cell migration in scratch wound and Boyden chamber assays.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Chalconas/síntese química , Chalconas/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Chalconas/química , Relação Dose-Resposta a Droga , Humanos , Células Jurkat , Camundongos , Modelos Químicos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Células NIH 3T3 , Polimerização/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
19.
J Clin Endocrinol Metab ; 96(10): 3106-14, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21849527

RESUMO

CONTEXT: CTNNB1/ß-catenin mutations and activation of Wnt/ß-catenin pathway are frequent in adult adrenocortical tumors (ACT), but data on childhood ACT are lacking. OBJECTIVE: The aim of the study was to investigate the presence of Wnt/ß-catenin pathway abnormalities in childhood ACT. PATIENTS AND METHODS: Clinicopathological findings and outcome of 62 childhood ACT patients were analyzed regarding CTNNB1 mutations and the expression of Wnt-related genes (CTNNB1; WNT4, a Wnt ligand; SFRP1, DKK3, and AXIN1, Wnt inhibitors; TCF7, a transcription factor; and MYC and WISP2, target genes) by quantitative PCR and immunohistochemistry. RESULTS: CTNNB1-activating mutations were found in only four of 62 ACT (6%), all of them harboring TP53 mutation. There was association between the presence of CTNNB1 mutations and death (P = 0.02). Diffuse ß-catenin accumulation was found in 71% of ACT, even in ACT without CTNNB1 mutations. Compared to normal adrenals, ACT presented increased expression of CTNNB1 (P = 0.008) and underexpression of Wnt inhibitor genes: DKK3 (P < 0.0001), SFRP1 (P = 0.05), and AXIN1 (P = 0.04). With regard to Wnt/ß-catenin target genes, ACT presented increased expression of WISP2 but lower expression of MYC. Higher overall survival was associated with underexpression of SFRP1 (P = 0.01), WNT4 (P = 0.004), and TCF7 (P < 0.01). CONCLUSIONS: CTNNB1 mutations are not common in childhood ACT but appear to associate with poor prognosis. Nevertheless, most ACT exhibit increased expression of ß-catenin and WISP2 and reduced expression of Wnt inhibitor genes (DKK3, SFRP1, and AXIN1). Thus, in addition to CTNNB1 mutations, other genetic events affecting the Wnt/ß-catenin pathway may be involved in childhood adrenocortical tumorigenesis.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Transdução de Sinais/fisiologia , Proteínas Wnt/fisiologia , beta Catenina/fisiologia , Adolescente , Neoplasias do Córtex Suprarrenal/genética , Proteína Axina/fisiologia , Proteínas de Sinalização Intercelular CCN , Criança , Pré-Escolar , Estudos de Coortes , DNA/genética , DNA/isolamento & purificação , Feminino , Humanos , Imuno-Histoquímica , Lactente , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Masculino , Mutação/fisiologia , Proteínas Proto-Oncogênicas c-myc/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Proteínas Repressoras , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Análise de Sobrevida , Fator 1 de Transcrição de Linfócitos T/fisiologia , Fatores de Transcrição/fisiologia , Resultado do Tratamento , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Wnt/antagonistas & inibidores , Proteínas Wnt/genética , Proteína Wnt4/fisiologia , beta Catenina/genética
20.
BMC Genomics ; 11: 462, 2010 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-20691070

RESUMO

BACKGROUND: To date, oil-rich plants are the main source of biodiesel products. Because concerns have been voiced about the impact of oil-crop cultivation on the price of food commodities, the interest in oil plants not used for food production and amenable to cultivation on non-agricultural land has soared. As a non-food, drought-resistant and oil-rich crop, Jatropha curcas L. fulfils many of the requirements for biofuel production. RESULTS: We have generated 13,249 expressed sequence tags (ESTs) from developing and germinating Jatropha seeds. This strategy allowed us to detect most known genes related to lipid synthesis and degradation. We have also identified ESTs coding for proteins that may be involved in the toxicity of Jatropha seeds. Another unexpected finding is the high number of ESTs containing transposable element-related sequences in the developing seed library (800) when contrasted with those found in the germinating seed library (80). CONCLUSIONS: The sequences generated in this work represent a considerable increase in the number of sequences deposited in public databases. These results can be used to produce genetically improved varieties of Jatropha with increased oil yields, different oil compositions and better agronomic characteristics.


Assuntos
Jatropha/genética , Óleos de Plantas/análise , Elementos de DNA Transponíveis , Bases de Dados de Ácidos Nucleicos , Perfilação da Expressão Gênica , Germinação , Jatropha/química , Jatropha/metabolismo , Óleos de Plantas/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo , Transcrição Gênica
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