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1.
Cancer Gene Ther ; 30(8): 1105-1113, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37041276

RESUMEN

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.


Asunto(s)
Neoplasias Encefálicas , Ependimoma , Humanos , Pronóstico , Factores de Transcripción/genética , Ependimoma/genética , Ependimoma/metabolismo , Neoplasias Encefálicas/genética , Perfilación de la Expresión Génica , Histona Desacetilasas/genética , Proteínas Represoras/genética
2.
Biochem Pharmacol ; 182: 114230, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32979352

RESUMEN

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.


Asunto(s)
Antineoplásicos/farmacología , Asparaginasa/farmacología , Productos Biológicos/farmacología , Fenómenos Inmunogenéticos/efectos de los fármacos , Lisosomas/inmunología , Péptido Hidrolasas/farmacología , Secuencia de Aminoácidos , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Asparaginasa/química , Asparaginasa/uso terapéutico , Productos Biológicos/química , Productos Biológicos/uso terapéutico , Bovinos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Pollos , Relación Dosis-Respuesta a Droga , Escherichia coli , Femenino , Caballos , Humanos , Fenómenos Inmunogenéticos/fisiología , Células Jurkat , Lisosomas/química , Ratones , Ratones Endogámicos BALB C , Péptido Hidrolasas/química , Péptido Hidrolasas/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Estructura Secundaria de Proteína
3.
Mol Genet Genomic Med ; 8(9): e1168, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32592449

RESUMEN

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.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/epidemiología , Frecuencia de los Genes , Mutación Missense , Población/genética , Proteína p53 Supresora de Tumor/genética , Neoplasias de la Corteza Suprarrenal/genética , Brasil , Femenino , Técnicas de Genotipaje/métodos , Humanos , Masculino , Prevalencia
5.
Anticancer Drugs ; 30(8): 828-837, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30932944

RESUMEN

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.


Asunto(s)
Antineoplásicos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucocitos Mononucleares/efectos de los fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Tiosemicarbazonas/química , Antineoplásicos/química , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Ciclo Celular , Proliferación Celular , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Potencial de la Membrana Mitocondrial , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Células Tumorales Cultivadas
6.
Nat Prod Res ; 33(11): 1633-1636, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29338345

RESUMEN

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.


Asunto(s)
Anacardium/química , Antineoplásicos Fitogénicos/farmacología , Extractos Vegetales/farmacología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Caspasa 3/genética , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Humanos , Fenoles/análisis , Hojas de la Planta/química , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología
7.
AMB Express ; 8(1): 178, 2018 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30382415

RESUMEN

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
Artículo en Inglés | LILACS | ID: biblio-954624

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Niño , Genes p53/genética , Proteína p53 Supresora de Tumor/genética , Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/genética , Mutación de Línea Germinal/genética , Predisposición Genética a la Enfermedad/genética , Linaje , Estudios Longitudinales , Estadificación de Neoplasias
9.
J Pediatr (Rio J) ; 94(4): 432-439, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28864397

RESUMEN

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.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/genética , Genes p53/genética , Predisposición Genética a la Enfermedad/genética , Mutación de Línea Germinal/genética , Proteína p53 Supresora de Tumor/genética , Niño , Preescolar , Femenino , Humanos , Lactante , Estudios Longitudinales , Masculino , Estadificación de Neoplasias , Linaje
10.
Cancer ; 123(16): 3150-3158, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28387921

RESUMEN

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.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/genética , Neoplasias de la Mama/genética , Neoplasias Gástricas/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Adulto , Brasil , Niño , Preescolar , Familia , Femenino , Predisposición Genética a la Enfermedad , Heterocigoto , Humanos , Lactante , Masculino , Persona de Mediana Edad , Neoplasias/genética , Adulto Joven
11.
Oncotarget ; 7(51): 84634-84644, 2016 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-27705928

RESUMEN

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.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Neoplasias de la Corteza Suprarrenal/metabolismo , Corteza Suprarrenal/metabolismo , Fosfoproteínas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Adolescente , Neoplasias de la Corteza Suprarrenal/genética , Neoplasias de la Corteza Suprarrenal/mortalidad , Carcinogénesis , Línea Celular Tumoral , Proliferación Celular , Niño , Preescolar , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Lactante , Masculino , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Fosfoproteínas/genética , Transducción de Señal , Análisis de Supervivencia , Factores de Transcripción , Proteínas Wnt/metabolismo , Proteínas Señalizadoras YAP , beta Catenina/metabolismo
12.
Eur J Med Chem ; 96: 504-18, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25951294

RESUMEN

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.


Asunto(s)
Anisoles/farmacología , Antineoplásicos/farmacología , Hidrazonas/farmacología , Microtúbulos/efectos de los fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Animales , Anisoles/síntesis química , Anisoles/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Hidrazonas/síntesis química , Hidrazonas/química , Ratones , Ratones Endogámicos NOD , Ratones SCID , Microtúbulos/metabolismo , Modelos Moleculares , Estructura Molecular , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Relación Estructura-Actividad , Tubulina (Proteína)/metabolismo , Células Tumorales Cultivadas
13.
Pediatr Blood Cancer ; 61(11): 1940-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25156210

RESUMEN

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.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/inmunología , Cadenas alfa de HLA-DP/genética , Cadenas beta de HLA-DP/genética , Cadenas alfa de HLA-DR/genética , Adolescente , Neoplasias de la Corteza Suprarrenal/mortalidad , Neoplasias de la Corteza Suprarrenal/patología , Niño , Preescolar , Femenino , Cadenas alfa de HLA-DP/análisis , Cadenas beta de HLA-DP/análisis , Cadenas alfa de HLA-DR/análisis , Humanos , Lactante , Masculino , Pronóstico
14.
J Clin Endocrinol Metab ; 99(7): E1209-16, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24712566

RESUMEN

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.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/genética , Corteza Suprarrenal/embriología , Corteza Suprarrenal/crecimiento & desarrollo , Carcinoma Corticosuprarrenal/genética , Proteínas Hedgehog/genética , Corteza Suprarrenal/metabolismo , Neoplasias de la Corteza Suprarrenal/metabolismo , Carcinoma Corticosuprarrenal/metabolismo , Adulto , Estudios de Casos y Controles , Células Cultivadas , Niño , Desarrollo Embrionario/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Proteínas Hedgehog/metabolismo , Humanos , Recién Nacido , Embarazo , Estudios Retrospectivos , Transducción de Señal/genética
15.
Clin Endocrinol (Oxf) ; 81(4): 503-10, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24717047

RESUMEN

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.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/metabolismo , Vía de Señalización Wnt/fisiología , Adolescente , Neoplasias de la Corteza Suprarrenal/genética , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Inmunohistoquímica , Lactante , Masculino , Persona de Mediana Edad , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Vía de Señalización Wnt/genética , Adulto Joven , beta Catenina/genética , beta Catenina/metabolismo
16.
Eur J Med Chem ; 63: 501-10, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23524161

RESUMEN

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.


Asunto(s)
Puntos de Control del Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Chalconas/síntesis química , Chalconas/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Chalconas/química , Relación Dosis-Respuesta a Droga , Humanos , Células Jurkat , Ratones , Modelos Químicos , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Células 3T3 NIH , Polimerizacion/efectos de los fármacos , Tubulina (Proteína)/metabolismo
17.
J Clin Endocrinol Metab ; 96(10): 3106-14, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21849527

RESUMEN

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.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/metabolismo , Transducción de Señal/fisiología , Proteínas Wnt/fisiología , beta Catenina/fisiología , Adolescente , Neoplasias de la Corteza Suprarrenal/genética , Proteína Axina/fisiología , Proteínas CCN de Señalización Intercelular , Niño , Preescolar , Estudios de Cohortes , ADN/genética , ADN/aislamiento & purificación , Femenino , Humanos , Inmunohistoquímica , Lactante , Péptidos y Proteínas de Señalización Intercelular/fisiología , Masculino , Mutación/fisiología , Proteínas Proto-Oncogénicas c-myc/fisiología , ARN Mensajero/genética , ARN Mensajero/aislamiento & purificación , Proteínas Represoras , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/genética , Análisis de Supervivencia , Factor 1 de Transcripción de Linfocitos T/fisiología , Factores de Transcripción/fisiología , Resultado del Tratamiento , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Wnt/antagonistas & inhibidores , Proteínas Wnt/genética , Proteína Wnt4/fisiología , beta Catenina/genética
18.
BMC Genomics ; 11: 462, 2010 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-20691070

RESUMEN

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.


Asunto(s)
Jatropha/genética , Aceites de Plantas/análisis , Elementos Transponibles de ADN , Bases de Datos de Ácidos Nucleicos , Perfilación de la Expresión Génica , Germinación , Jatropha/química , Jatropha/metabolismo , Aceites de Plantas/metabolismo , Semillas/química , Semillas/genética , Semillas/metabolismo , Transcripción Genética
19.
J Clin Oncol ; 28(11): 1911-8, 2010 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-20212252

RESUMEN

PURPOSE To describe event-free survival (EFS) and toxicities in children with low-risk acute lymphoblastic leukemia (ALL) assigned to receive either continuous 6-mercaptopurine (6-MP) and weekly methotrexate (MTX) or intermittent 6-MP with intermediate-dose MTX, as maintenance treatment. PATIENTS AND METHODS Between October 1, 2000, and December 31, 2007, 635 patients with low-risk ALL were enrolled onto Brazilian Childhood Cooperative Group for ALL Treatment (GBTLI) ALL-99 protocol. Eligible children (n = 544) were randomly allocated to receive either continuous 6-MP/MTX (group 1, n = 272) or intermittent 6-MP (100 mg/m(2)/d for 10 days, with 11 days resting) and MTX (200 mg/m(2) every 3 weeks; group 2, n = 272). RESULTS The 5-year overall survival (OS) and EFS were 92.5% +/- 1.5% SE and 83.6% +/- 2.1% SE, respectively. According to maintenance regimen, the OS was 91.4% +/- 2.2% SE (group 1) and 93.6% +/- 2.1% SE (group 2; P = .28) and EFS 80.9% +/- 3.2% SE (group 1) and 86.5% +/- 2.8% SE (group 2; P = .089). Remarkably, the intermittent regimen led to significantly higher EFS among boys (85.7% v 74.9% SE; P = .027), while no difference was seen for girls (87.0% v 88.8% SE; P = .78). Toxic episodes were recorded in 226 and 237 children, respectively. Grade 3 to 4 toxic events for groups 1 and 2 were, respectively, 273 and 166 for hepatic dysfunction (P = .002), and 772 and 636 for hematologic episodes (P = .005). Deaths on maintenance were: seven (group 1) and one (group 2). CONCLUSION The intermittent use of 6-MP and MTX in maintenance is a less toxic regimen, with a trend toward better long-term EFS. Boys treated with the intermittent schedule had significantly better EFS.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adolescente , Brasil , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Mercaptopurina/administración & dosificación , Metotrexato/administración & dosificación , Estadificación de Neoplasias , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Estudios Prospectivos , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento
20.
Pediatr Blood Cancer ; 53(6): 996-1004, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19672972

RESUMEN

BACKGROUND: Increased activity of multidrug resistance (MDR) genes has been associated with treatment failure in acute leukemias, although with controversial reports. The objective of the present study was to assess the expression profile of the genes related to MDR: ABCB1, ABCC1, ABCC3, ABCG2, and LRP/MVP in terms of the clinical and biological variable and the survival of children with acute lymphoblastic leukemia (ALL). PROCEDURE: The levels of mRNA expression of the drug resistance genes ABCB1, ABCC1, ABCC3, ABCG2, and LRP/MVP were analyzed by quantitative real-time PCR using the median values as cut-off points, in consecutive samples from 140 children with ALL at diagnosis. RESULTS: Expression levels of the ABCG2 gene in the patient group as a whole (P = 0.05) and of the ABCG2 and ABCC1 genes in patients classified as being at high risk were associated with higher rates of 5-year event-free survival (EFS) (P = 0.04 and P = 0.01). Expression levels of the ABCG2 gene below the median were associated with a greater chance of death related to treatment toxicity for the patient group as a whole (P = 0.009) and expression levels below the median of the ABCG2 and ABCC1 genes were associated with a greater chance of death due to treatment toxicity for the high-risk group (P = 0.02 and P = 0.03, respectively). CONCLUSION: The present data suggest a low participation of the drug efflux genes in treatment failure in patients with childhood ALL. However, the low expression of some of these genes may be associated with a higher death risk related to treatment toxicity.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Genes MDR/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas de Neoplasias/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Niño , Preescolar , Perfilación de la Expresión Génica , Humanos , Lactante , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , ARN Mensajero/análisis , Medición de Riesgo , Análisis de Supervivencia , Tasa de Supervivencia , Insuficiencia del Tratamiento
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