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1.
Colomb. med ; 52(3): e4004227, July-Sept. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1360381

RESUMO

Abstract gastroschisis is a congenital structural defect of the abdominal wall, most often to the right of the umbilicus, through which the abdominal viscera protrude. Its developmental, etiological and epidemiological aspects have been a hot topic of controversy for a long time. However, recent findings suggest the involving of genetic and chromosomal alterations and the existence of a stress-inducing pathogenetic pathway, in which risk factors such as demographic and environmental ones can converge. . We have conducted a review of the medical literature that gathers information on the embryonic development of the ventral body wall, the primitive intestine, and the ring-umbilical cord complex, as well as on the theories about its origin, pathogenesis and recent epidemiological evidence, for which we consulted bibliographic databases and standard search engines


Resumen La gastrosquisis es un defecto estructural congénito de la pared abdominal, localizado con mayor frecuencia a la derecha del ombligo, a través del cual sobresalen las vísceras abdominales. Durante mucho tiempo, sus aspectos evolutivos, etiológicos y epidemiológicos han sido un tema candente de controversia, aunque hallazgos recientes sugieren la participación de alteraciones genéticas, cromosómicas, y la existencia de una vía patogénica inductora de estrés, en la que factores de riesgo como los demográficos y ambientales pueden converger. Con el objetivo de ampliar la frontera del conocimiento sobre una malformación que ha mostrado una creciente prevalencia global, hemos efectuado una revisión que incluye información, del desarrollo embrionario de la pared corporal ventral, el intestino primitivo, el complejo anillo-cordón umbilical, y de las teorías acerca de su origen, patogénesis e información epidemiológica reciente.

2.
Colomb Med (Cali) ; 52(3): e4004227, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35431359

RESUMO

gastroschisis is a congenital structural defect of the abdominal wall, most often to the right of the umbilicus, through which the abdominal viscera protrude. Its developmental, etiological and epidemiological aspects have been a hot topic of controversy for a long time. However, recent findings suggest the involving of genetic and chromosomal alterations and the existence of a stress-inducing pathogenetic pathway, in which risk factors such as demographic and environmental ones can converge. To expand the frontier of knowledge about a malformation that has showed a growing global prevalence, we have conducted a review of the medical literature that gathers information on the embryonic development of the ventral body wall, the primitive intestine, and the ring-umbilical cord complex, as well as on the theories about its origin, pathogenesis and recent epidemiological evidence, for which we consulted bibliographic databases and standard search engines.


La gastrosquisis es un defecto estructural congénito de la pared abdominal, localizado con mayor frecuencia a la derecha del ombligo, a través del cual sobresalen las vísceras abdominales. Durante mucho tiempo, sus aspectos evolutivos, etiológicos y epidemiológicos han sido un tema candente de controversia, aunque hallazgos recientes sugieren la participación de alteraciones genéticas, cromosómicas, y la existencia de una vía patogénica inductora de estrés, en la que factores de riesgo como los demográficos y ambientales pueden converger.Con el objetivo de ampliar la frontera del conocimiento sobre una malformación que ha mostrado una creciente prevalencia global, hemos efectuado una revisión que incluye información, del desarrollo embrionario de la pared corporal ventral, el intestino primitivo, el complejo anillo-cordón umbilical, y de las teorías acerca de su origen, patogénesis e información epidemiológica reciente.


Assuntos
Parede Abdominal , Gastrosquise , Parede Abdominal/anormalidades , Parede Abdominal/patologia , Feminino , Gastrosquise/epidemiologia , Gastrosquise/etiologia , Humanos , Gravidez , Prevalência , Fatores de Risco
3.
Colomb Med (Cali) ; 51(1): e3646, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32952228

RESUMO

INTRODUCTION: Car painters are routinely exposed to organic solvents classified as carcinogenic and mutagenic substances. OBJECTIVE: To characterize the population susceptibility and evaluate the genotoxic effects of exposure to organic solvents. METHODS: A cross-sectional study comparing a group of car painters exposed to organic solvents with a non-exposed group. CYP2E1 polymorphisms and the presence of micronuclei in lymphocytes were determined. RESULTS: One hundred twenty-two workers participated in the study: 62 who worked in car paint shops and were exposed to solvents, and 60 who were not exposed. There were statistically significant differences between the two groups regarding micronucleated cells and nucleoplasmic bridges frequencies (p= 0.042 and p= 0.046, respectively; exact likelihood ratio). Significant differences were found at the interaction between the CYP2E1 genotype c1c1 and occupational exposure to solvents, with higher frequencies of micronuclei (p= 0.013) and micronucleated cells (p= 0.015). However, when the frequencies of micronuclei, micronucleated cells and nucleoplasmic bridges in the exposure group were compared between the c1c1 and c2c2/c1c2 allele groups of the CYP2E1 polymorphism, statistically significant differences were found. CONCLUSIONS: This study confirms that when workers with CYP2E1 polymorphisms, specifically the c1c1 genotype, are exposed to organic solvents, they are more likely to have somatic cell mutations, a condition associated with increased susceptibility to diseases such as cancer.


INTRODUCCIÓN: Los pintores de vehículos automotores están rutinariamente expuestos a agentes como los solventes orgánicos, capaces de producir efectos mutágenos y carcinógenos. OBJETIVO: Caracterizar la susceptibilidad poblacional y evaluar los efectos genotóxicos debidos a la exposición a solventes orgánicos. MÉTODOS: Estudio de corte transversal que comparó a un grupo de pintores de carros expuestos a solventes orgánicos con un grupo de personas no expuestas. Fueron determinados tanto los polimorfismos de CYP2E1 como la presencia de micronúcleos en linfocitos. RESULTADOS: Participaron 122 personas, 62 trabajadores de talleres de pintura de autos expuestos a solventes y 60 personas no expuestas. Con relación al cuestionario Q 16, 32% de los expuestos refirieron síntomas sugestivos de neurotoxicidad. Las frecuencias de células micronucleadas y de puentes nucleoplásmicos fueron significativamente mayores en los expuestos que en los no expuestos: p= 0.042 y p= 0.046, respectivamente, Razón de verosimilitud exacta). Fueron halladas diferencias significativas en la interacción de CYP2E1 (c1c1) y la exposición ocupacional a solventes, con mayores frecuencias de micronúcleos (p= 0.013) y de células micronucleadas (p= 0.015). CONCLUSIONES: Este estudio reafirma que los trabajadores expuestos a solventes orgánicos con polimorfismos de CYP2E1, específicamente con genotipo c1c1, tienen mayor probabilidad de presentar mutaciones en las células somáticas, condición asociada con una mayor susceptibilidad a enfermedades como el cáncer.


Assuntos
Carcinógenos/toxicidade , Citocromo P-450 CYP2E1/genética , Exposição Ocupacional/efeitos adversos , Pintura/toxicidade , Solventes/toxicidade , Adulto , Alelos , Automóveis , Estudos de Casos e Controles , Colômbia , Estudos Transversais , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/ultraestrutura , Masculino , Testes para Micronúcleos/métodos , Pessoa de Meia-Idade , Testes de Mutagenicidade , Síndromes Neurotóxicas/diagnóstico , Equipamento de Proteção Individual , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição
4.
Colomb. med ; 51(1): e3646, Jan.-Mar. 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1124610

RESUMO

Abstract Introduction: Car painters are routinely exposed to organic solvents classified as carcinogenic and mutagenic substances. Objective: To characterize the population susceptibility and evaluate the genotoxic effects of exposure to organic solvents. Methods: A cross-sectional study comparing a group of car painters exposed to organic solvents with a non-exposed group. CYP2E1 polymorphisms and the presence of micronuclei in lymphocytes were determined. Results: One hundred twenty-two workers participated in the study: 62 who worked in car paint shops and were exposed to solvents, and 60 who were not exposed. There were statistically significant differences between the two groups regarding micronucleated cells and nucleoplasmic bridges frequencies (p=0.042 and p=0.046, respectively; exact likelihood ratio). Significant differences were found at the interaction between the CYP2E1 genotype c1c1 and occupational exposure to solvents, with higher frequencies of micronuclei (p= 0.013) and micronucleated cells (p= 0.015). However, when the frequencies of micronuclei, micronucleated cells and nucleoplasmic bridges in the exposure group were compared between the c1c1 and c2c2/c1c2 allele groups of the CYP2E1 polymorphism, statistically significant differences were found. Conclusions: This study confirms that when workers with CYP2E1 polymorphisms, specifically the c1c1 genotype, are exposed to organic solvents, they are more likely to have somatic cell mutations, a condition associated with increased susceptibility to diseases such as cancer


Resumen Introducción: Los pintores de vehículos automotores están rutinariamente expuestos a agentes como los solventes orgánicos, capaces de producir efectos mutágenos y carcinógenos. Objetivo: Caracterizar la susceptibilidad poblacional y evaluar los efectos genotóxicos debidos a la exposición a solventes orgánicos. Métodos: Estudio de corte transversal que comparó a un grupo de pintores de carros expuestos a solven tes orgánicos con un grupo de personas no expuestas. Fueron determinados tanto los polimorfismos de CYP2E1 como la presencia de micronúcleos en linfocitos. Resultados: Participaron 122 personas, 62 trabajadores de talleres de pintura de autos expuestos a solventes y 60 personas no expuestas. Con relación al cuestionario Q 16, 32% de los expuestos refirieron síntomas sugestivos de neurotoxicidad. Las frecuencias de células micronucleadas y de puentes nucleoplásmicos fueron significativamente mayores en los expuestos que en los no expuestos: p= 0.042 y p= 0.046, respectivamente, Razón de verosimilitud exacta). Fueron halladas diferencias significativas en la interacción de CYP2E1 (c1c1) y la exposición ocupacional a solventes, con mayores frecuencias de micronúcleos (p= 0.013) y de células micronucleadas (p= 0.015). Conclusiones: Este estudio reafirma que los trabajadores expuestos a solventes orgánicos con polimorfismos de CYP2E1, específicamente con genotipo c1c1, tienen mayor probabilidad de presentar mutaciones en las células somáticas, condición asociada con una mayor susceptibilidad a enfermedades como el cáncer


Assuntos
Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Pintura/toxicidade , Solventes/toxicidade , Carcinógenos/toxicidade , Exposição Ocupacional/efeitos adversos , Citocromo P-450 CYP2E1/genética , Polimorfismo Genético , Automóveis , Polimorfismo de Fragmento de Restrição , Linfócitos/efeitos dos fármacos , Linfócitos/ultraestrutura , Testes para Micronúcleos/métodos , Estudos de Casos e Controles , Estudos Transversais , Colômbia , Síndromes Neurotóxicas/diagnóstico , Alelos , Equipamento de Proteção Individual , Testes de Mutagenicidade
5.
J Occup Med Toxicol ; 11: 33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27429640

RESUMO

BACKGROUND: For several years, cell-free DNA has been emerging as an important biomarker for non-invasive diagnostic in a wide range of clinical conditions and diseases. The limited information available on the genotoxic effects associated with occupational exposure to car paints, as well as the fact that up-to-date there are not reports about cell-free DNA measurements for assessing this condition, led us to evaluate the DNA damage caused by the occupational exposure to organic solvents contained in car paints, through the quantification of the cell-free DNA and the comet assay, in a sample of 33 individuals taken from 10 automobile paint shops located in Bogota DC, Colombia. RESULTS: By applying the two methods, cell-free DNA and comet assay, we found a significant increase in the extent of DNA damage in the exposed individuals compared with the non-exposed ones within the control group. CONCLUSIONS: Our findings provide useful information about the cell-free DNA levels in this type of exposure and can be considered as a support tool that contributes to the diagnosis of genotoxic damage in individuals occupationally exposed to car paints.

6.
Mol Cytogenet ; 9: 46, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27325915

RESUMO

BACKGROUND: Painters are exposed to an extensive variety of harmful substances like aromatic hydrocarbons used as solvents and paint removers, some of which have shown clastogenic activity. These substances constitute a complex mixture of chemicals which contain well-known genotoxicants, such as Benzene, Toluene and Xylene. Thus, chronic occupational exposure to such substances may be considered to possess genotoxic risk. In Colombia the information available around the genotoxic damage (Chromosomal and DNA damage) in car paint shop workers is limited and the knowledge of this damage could contribute not only to a better understanding of the carcinogenic effect of this kind of substances but also could be used as biomarkers of occupational exposure to genotoxic agents. RESULTS: In this study, the genotoxic effect of aromatic hydrocarbons was assessed in peripheral blood lymphocytes of 24 workers occupationally exposed and 24 unexposed donors, by using Cytogenetic analysis and comet assay. A high frequency of Chromosomal alterations was found in the exposed group in comparison with those observed in the unexposed group. Among the total of CAs observed in the exposed group, fragilities were most frequently found (100 %), followed by chromosomal breaks (58 %), structural (41.2 %) and numerical chromosomal alterations (21 %). Numerical chromosomal alterations, fragilities and chromosomal breaks showed significant differences between exposed and unexposed groups. Among the fragilities, fra(9)(q12) was the most frequently observed. DNA damage index was also significantly higher in the exposed group compared to the unexposed group (p < 0.000). CONCLUSIONS: Our results revealed that occupational exposure to aromatic hydrocarbons is significantly associated with Chromosomal and DNA damage in car paint shops workers and are also indicative of high chromosomal instability. The high frequency of both Chromosomal Alterations and DNA Damage Index observed in this study indicates an urgent need of intervention not only to prevent the increased risk of developing cancer but also to the application of strict health control and motivation to the use of appropriate protecting devices during work.

7.
Iran J Basic Med Sci ; 18(9): 837-55, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26523216

RESUMO

Pigment epithelium-derived factor (PEDF) is a glycoprotein that belongs to the family of non-inhibitory serpins. The broad spectrum of PEDF biological activity is evident when considering its effects in promoting cell survival and proliferation, as well as its antiangiogenic, antitumor, and anti-metastatic properties. Although the structural domains of the PEDF gene that mediate such diverse effects and their mechanisms of action have not been completely elucidated, there is a large body of evidence describing their diverse range of activities; this evidence combined with the regulation of PEDF expression by sex steroids and their receptors have led to the idea that PEDF is not only a diagnostic and prognostic marker for certain diseases such as cancer, but is also a potential therapeutic target. In this manner, this paper aims to generally review the regulation of PEDF expression and PEDF interactions, as well as the findings that relate PEDF to the role of estrogens and estrogen receptors. In addition, this manuscript will review major advances toward potential therapeutic applications of PEDF.

8.
Invest Clin ; 54(2): 186-205, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23947008

RESUMO

The epithelial-mesenchymal transition (EMT) is a biological phenomenon responsible for the formation of different tissues and organs during normal metazoan development. Because of the connection of the EMT with the pathogenesis of certain diseases, such as cancer, the attention of the scientific community has been directed towards the search for and identification of effective therapeutic targets. These targets include signal transduction in cancerous stem cells and the use of microRNAs, which would inhibit EMT-associated phenotypic changes and tumoral progression. In an attempt to compile relevant and current information, this work addresses concepts that define the EMT and the advances in this field. The wealth of knowledge gained from areas such as the loss of cell polarity and intracellular adhesion complexes, the signaling pathways implicated, microRNA participation in this process, and stemness acquisition in embryonic and cancerous cells, all of which allow for the visualization of promising perspectives, particularly, methods for targeting advanced malignancies, are presented herein.


Assuntos
Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal , Terapia de Alvo Molecular , Neoplasias/terapia , Animais , Antineoplásicos/uso terapêutico , Adesão Celular , Moléculas de Adesão Celular/fisiologia , Diferenciação Celular , Movimento Celular , Polaridade Celular , Transformação Celular Neoplásica , Progressão da Doença , Desenvolvimento Embrionário , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/fisiologia , Fibrose , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , MicroRNAs/fisiologia , Proteínas de Neoplasias/fisiologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , RNA Neoplásico/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
9.
Invest. clín ; 54(2): 186-205, jun. 2013. ilus
Artigo em Inglês | LILACS | ID: lil-740348

RESUMO

The epithelial-mesenchymal transition (EMT) is a biological phenomenon responsible for the formation of different tissues and organs during normal metazoan development. Because of the connection of the EMT with the pathogenesis of certain diseases, such as cancer, the attention of the scientific community has been directed towards the search for and identification of effective therapeutic targets. These targets include signal transduction in cancerous stem cells and the use of microRNAs, which would inhibit EMT-associated phenotypic changes and tumoral progression. In an attempt to compile relevant and current information, this work addresses concepts that define the EMT and the advances in this field. The wealth of knowledge gained from areas such as the loss of cell polarity and intracellular adhesion complexes, the signaling pathways implicated, microRNA participation in this process, and stemness acquisition in embryonic and cancerous cells, all of which allow for the visualization of promising perspectives, particularly, methods for targeting advanced malignancies, are presented herein.


La transición epitelio-mesenquimática (TEM) es el fenómeno biológico responsable de la formación de los diferentes tejidos y órganos durante el desarrollo normal de los organismos metazoarios. En razón de su conexión con la patogénesis de ciertas enfermedades como el cáncer, la atención de la comunidad científica se ha redireccionado hacia la búsqueda e identificación de blancos terapéuticos efectivos, como la transducción de señales de las células madre cancerosas o la utilización de microARNs, que permitirían bloquear los cambios fenotípicos asociados con la TEM y, por ende, la progresión tumoral. En un intento por recopilar información relevante y actualizada, el presente trabajo aborda conceptos que definen a la TEM y avances alcanzados en este campo. El acervo de conocimiento obtenido en aspectos como pérdida de la polaridad celular y de los complejos de adhesión intercelular, vías de señalización implicadas y participación de los microARNs en el proceso, así como adquisición de stemness o troncalidad, tanto en células embrionarias como cancerosas, hace posible visualizar perspectivas promisorias, en especial en lo que se refiere a las terapias contra las malignidades de alto grado.


Assuntos
Animais , Humanos , Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal , Terapia de Alvo Molecular , Neoplasias/terapia , Antineoplásicos/uso terapêutico , Adesão Celular , Diferenciação Celular , Movimento Celular , Polaridade Celular , Transformação Celular Neoplásica , Moléculas de Adesão Celular/fisiologia , Progressão da Doença , Desenvolvimento Embrionário , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/fisiologia , Fibrose , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , MicroRNAs/fisiologia , Proteínas de Neoplasias/fisiologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , RNA Neoplásico/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
10.
Rev. cienc. salud (Bogotá) ; 9(3): 219-228, dic. 2011. graf, tab
Artigo em Inglês | LILACS, COLNAL | ID: lil-650015

RESUMO

GAPDH can bind single-strand telomere DNA both in vitro and in vivo. Thus, it was hypothesised that GAPDH has an important role in protecting the telomeres, role that could be shared with TRF2, a well-known telomeric protein involved in a myriad of functions related to telomere homeostasis. Objective: The aim of this study was to determine if there was a correlation between the expression of these genes in the in vitro ovarian surface epithelium. Materials and methods: The relative expression of each gene was established by qRT-PCR in primary cell cultures of the ovarian surface epithelium from 22 healthy mestizo Colombian donors. Results: The Kendall and Spearman non-parametric tests established a significant correlation between the levels of expression in subsequent passages of the cell line, in an age-independent way. Conclusion: Our findings suggest a synergistic effect between TRF2 and GAPDH that could counter telomere shortening in vitro.


Se ha demostrado que la proteína GAPDH se puede unir al ADN telomérico de cadena sencilla, tanto in vitro como in vivo. Por lo tanto, se ha planteado la hipótesis de que la GAPDH juega un papel importante en la protección de los telómeros, papel que podría ser compartido con la TRF2, proteína que participa en una gran variedad de funciones relacionadas con la homeostasis telomérica. Objetivo: el objetivo de este estudio fue determinar si existe una correlación entre la expresión de ambos genes en el epitelio superficial del ovario in vitro. Materiales y métodos: la expresión relativa de cada gen fue establecida mediante qRT-PCR, en cultivos primarios de células del epitelio superficial del ovario provenientes de un grupo de 22 donantes colombianas mestizas sanas. Resultados: las pruebas no paramétricas de Kendall y Spearman permitieron establecer que existe una correlación significativa entre los niveles de expresión de GAPDH y TRF2 a lo largo de la historia replicativa de los cultivos, en forma independiente de la edad de las donantes. Conclusión: nuestros resultados sugieren un efecto sinérgico entre TRF2 y GAPDH, que podría estar orientado a contrarrestar la reducción de los telómeros in vitro.


Tem se demonstrado que GAPDH pode-se unir ao DNA telomérico de cadeia simples, tanto in vitro quanto in vivo. Portanto, tem se apresentado a hipótese de que GAPDH joga um papel importante na proteção dos telómeros, papel que poderia ser compartilhado com TRF2, proteína que participa em uma grande variedade de funções relacionadas com a homeostase telomérica. Objetivo. O objetivo deste estudo foi determinar se existe uma correlação entre a expressão de ambos os genes no epitélio superficial do ovário in vitro. Materiais e métodos: A expressão relativa de cada gene foi estabelecida mediante qRT-PCR em cultivos primários de células do epitélio superficial do ovário provenientes de um grupo de 22 doadoras colombianas mestiças sanas. Resultados. As provas não paramétricas de Kendall e Spearman permitiram estabelecer que existe uma correlação significativa entre os níveis de expressão de GAPDH e TRF2 ao longe da história replicativa dos cultivos, em forma independente da idade das doadoras. Conclusão. Nossos resultados sugerem um efeito sinérgico entre TRF2 e GAPDH que poderia estar orientado a contra-arrestar a redução dos telómeros in vitro.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Expressão Gênica , Técnicas In Vitro , Telômero , Senescência Celular , Colômbia , Cultura Primária de Células , Correlação de Dados
11.
Rev. cienc. salud (Bogotá) ; 9(1): 17-31, Apr. 2011. ilus, tab, graf
Artigo em Espanhol | LILACS, COLNAL | ID: lil-650007

RESUMO

Introducción: Un campo de investigación creciente de la biología es la senescencia celular, mecanismo que ha sido asociado -bajo determinadas circunstancias- con la transformación maligna. Teniendo en cuenta la elevada incidencia de cáncer ovárico y su génesis preferencial a partir del epitelio superficial del ovario, así como la posibilidad de ocurrencia de una transición epitelio-mesenquimática, se evaluó, tanto el crecimiento in vitro de los fibroblastos del estroma cortical, como la actividad a pH 6 de la β-galactosidasa, enzima cuya expresión ha sido clásicamente considerada como marcador de senescencia replicativa. Metodología: 48 muestras de fibroblastos de la corteza ovárica provenientes de donantes sin antecedentes de cáncer fueron cultivadas en forma seriada hasta el final de su vida replicativa. Mediante el método quimioluminiscente, en cada pase fue cuantificada la actividad β-galactosidasa a pH 6. Como control se utilizaron cultivos de células del epitelio superficial ovárico de las mismas donantes. La actividad enzimática fue también evaluada en fibroblastos previamente inducidos a senescencia con peróxido de hidrógeno. Resultados: Las lecturas de actividad enzimática, analizadas en conjunto con la capacidad replicativa, indican que los cultivos de fibroblastos alcanzaron el estado senescente hacia los pases 4-5, lo que también ocurrió con las células epiteliales. Los fibroblastos inducidos a senescencia mostraron valores variables de actividad enzimática. Conclusiones: La semejanza entre los fibroblastos y las células epiteliales en cuanto al inicio de la senescencia podría estar relacionado con la transición epitelio-mesenquimática que ha sido descrita como factor de riesgo de cáncer derivado del epitelio superficial ovárico. Valores bajos de actividad β-galactosidasa podrían sugerir que, en algunos casos, ocurrió inactivación de las vías de respuesta al estrés oxidativo.


Introduction: A growing biological research field is the cellular senescence, a mechanism that has been associated, under certain circumstances, with malignant transformation. Given the high incidence of ovarian cancer and its main origin from the ovarian surface epithelium, as well as the possibility that an epithelial-mesenchymal transition occurs, we evaluated both the in vitro growth of stromal fibroblasts from the ovarian cortex and their β-galactosidase activity at pH 6, enzyme whose expression is considered as a marker of replicative senescence. Methods: 48 samples of ovarian cortical fibroblasts from donors without a history of cancer were serially cultured until the end of their replicative life. β-galactosidase activity at pH 6 was quantified in each passage by the chemiluminiscent method. As control, we used ovarian epithelial cell cultures from the same donors. The enzyme activity was also evaluated in fibroblasts previously induced to senescence by exposure to hydrogen peroxide. Results: The analysis of the enzyme activity and the replicative capacity taken together showed that the fibroblast cultures reached the senescent state at passages 4-5, as what happened with the control epithelial cells. Fibroblasts induced to senescence showed high variability in the values of enzymatic activity. Conclusions: The similarity between both types of cells in reaching the senescent state deserves to be taken into account in relation to the epithelial-mesenchymal transition that has been proposed to explain their behavior in the genesis of cancer arising from ovarian surface epithelium. Low β-galactosidase activity values at pH 6 would suggest possible inactivation of the response pathways to oxidative stress.


Introdução: um campo de pesquisa crescente da biologia é a senescência celular, mecanismo que tem sido associado, sob determinadas circunstancias, com a transformação maligna. Tendo em conta a elevada incidência de câncer ovariano e sua gênese preferencial a partir do epitélio superficial do ovário, assim como a possibilidade de ocorrência de uma transição epitélio-mesenquimática, se avaliou, tanto o crescimento in vitro dos fibroblastos do estroma cortical, como a atividade a pH 6 da β-galactosidase, enzima cuja expressão tem sido classicamente considerada como marcador de senescência replicativa. Metodologia: 48 amostras de fibroblastos do córtex ovariano provenientes de doadores sem antecedentes de câncer foram cultivadas em forma seriada até o final de sua vida replicativa. Mediante o método quimioluminescente, em cada passe foi quantificada a atividade β-galactosidase a pH 6. Como controle utilizou-se cultivos de células do epitélio superficial ovariano das mesmas doadoras. A atividade enzimática foi também avaliada em fibroblastos previamente induzidos a senescência com peróxido de hidrogeno. Resultados: as leituras da atividade enzimática, analisada em conjunto com a capacidade replicativa, indicam que os cultivos de fibroblastos alcançaram o estado senescente para os passes 4-5, o que também ocorreu com as células epiteliais. Os fibroblastos induzidos a senescência mostraram valores variáveis de atividade enzimática. Conclusões:as semelhanças entre os fibroblastos e as células epiteliais em quanto ao inicio da senescência poderia estar relacionado com a transição epitélio-mesenquimática que tem sido descrita como fator de risco de câncer derivado do epitélio superficial ovariano. Valores baixos de atividade β-galactosidase poderiam sugerir que, em alguns casos, ocorreu inativação das vias de resposta ao estresse oxidativo.


Assuntos
Humanos , Feminino , beta-Galactosidase , Neoplasias Ovarianas , Senescência Celular , Transição Epitelial-Mesenquimal , Fibroblastos
12.
Invest. clín ; 51(4): 541-551, dic. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-630911

RESUMO

Our objective was to determine the presence of chromosomal abnormalities in primary cultures of ovarian surface epithelial cells in women of different ages with no history of cancer. Throughout conventional cytogenetic techniques, we analyzed chromosome spreads of cultured ovarian epithelial cells from 10 donors who were 50 or more years old (B) and 16 controls between 20 and 49 years old (A), belonging to the mestizo population in Bogota DC, Colombia. Of the 26 cultures that were analyzed in passage 1, 61.5% had an abnormal chromosome complement (62.5% in A, and 60% in B). Abnormalities included polyploidies, endoduplications and monosomies. Deletions in chromosomes 3 and 11 were found in just one metaphase. None of the samples showed weaknesses or breakpoints. After transforming and applying the exact student’s t-test for variance heterogeneity, we found significant differences in the frequency of metaphases, that were higher in A than in B (p=0.05), and in the frequency of polyploidies, which were higher in B than in A (p=0.044). Through the application of the Mann-Whitney test, we determined that the frequency of endoduplications was higher in A than in B (p=0.126), without reaching significant differences. There were no significant differences in the frequency of monosomies. The level of significance was set at p £ 0.05. Taking into account that polyploidization is a marker of chromosomal instability and that the risk of cancer arising from the ovarian surface epithelium augments substantially after menopause, the increase in the frequency of age-associated polyploidies could be used as a predictor of ovarian cancer in women from an ethnically homogeneous population as the mestizo one in Bogota DC.


El objetivo del presente trabajo fue determinar la presencia de anormalidades cromosómicas en cultivos primarios de células del epitelio superficial ovárico en mujeres de diferentes edades, sin antecedentes de cáncer. Mediante técnicas de citogenética convencional fueron analizados extendidos de células epiteliales ováricas histológicamente normales, provenientes de cultivos primarios de 10 donantes de 50 o más años (B) y de 16 donantes entre 20 y 49 años que se utilizaron como grupo control (A), pertenecientes a la población mestiza de Bogotá DC, Colombia. De 26 cultivos examinados en pase 1, 61,5% presentó complemento cromosómico anormal, 62,5% en A y 60% en B. Las anomalías numéricas halladas, todas en mosaico, incluyeron poliploidías, endoduplicaciones y monosomías. En una única célula en metafase de un cultivo, se presentaron deleciones en los cromosomas 3 y 11. Ninguna muestra presentó fragilidades o roturas. Previa aplicación de transformaciones, con la prueba exacta t-student para varianzas heterogéneas, se encontraron diferencias significativas en la frecuencia de células con metafase normal, mayor en A que en B (p=0,05) y en la de poliploidías, mayor en B que en A (p=0,044). Con la prueba exacta de Mann-Whitney se determinó que la frecuencia de endoduplicaciones en A fue mayor que en B (p=0,126), sin alcanzar diferencias significativas y que no hubo diferencias significativas en la frecuencia de monosomías. El nivel de significación fue p £ 0,05. Si se tiene en cuenta que la poliploidización es un marcador de inestabilidad cromosómica y, que además, el riesgo de aparición de cáncer derivado del epitelio superficial del ovario aumenta sustancialmente después de la menopausia, el incremento en la frecuencia de poliploidías asociado con la edad podría ser utilizado como predictor de cáncer ovárico en mujeres de una población étnicamente homogénea como la población mestiza de Bogotá DC.


Assuntos
Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Aberrações Cromossômicas , Células Epiteliais/ultraestrutura , Ovário/citologia , Fatores Etários , Aneuploidia , Transformação Celular Neoplásica/genética , Células Cultivadas/ultraestrutura , Suscetibilidade a Doenças , Cariotipagem , Metáfase , Índice Mitótico , Neoplasias Ovarianas/genética , Pós-Menopausa
13.
Invest. clín ; 51(3): 351-367, Sept. 2010. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-574452

RESUMO

La actividad de la ß-galactosidasa refleja la tasa de envejecimiento celular in vitro. Mediante quimioluminiscencia se cuantificó dicha actividad a pH 6 en células epiteliales ováricas provenientes de 28 donantes sin antecedentes de cáncer. Las células fueron cultivadas en forma seriada hasta alcanzar el estado de detención permanente de crecimiento. Durante la fase de crecimiento exponencial, todos los cultivos mostraron un patrón semejante de crecimiento y una baja actividad ß-galactosidasa. Sin embargo, el inicio de la disminución de la capacidad replicativa que caracteriza el final de dicha fase, así como el inicio de la fase estacionaria o senescente presentaron un aumento significativo en la actividad enzimática. Nuestros resultados mostraron que la actividad ß-galactosidasa puede ser considerada como marcador de senescencia replicativa del epitelio superficial del ovario a pH 6.


ß-galactosidase activity reflects the rate of cellular aging in vitro. Such activity was quantified at pH 6 in ovarian epithelial cells from 28 donors without a history of cancer, by the chemoluminiscent method. The cells were serially cultured until they achieved the state of permanent growth arrest. During the exponential growth phase, all cultures showed a similar pattern of growth and low ß-galactosidase activity. However, both in the onset of decrease replicative activity, as well as in the onset of the stationary phase, there was a significant rise in the enzyme activity. Our results showed that ß-galactosidase activity can be considered as a replicative senescence marker of the ovarian surface epithelium at pH 6.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Senescência Celular , Células Epitelioides , Ovário/citologia , beta-Galactosidase/administração & dosagem , Biomarcadores/análise
14.
Int. j. morphol ; 28(1): 37-50, Mar. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-579280

RESUMO

Senescence was rendered a tumor suppressor mechanism based on the observation of its protective effect against cancer in young organisms under conditions of oncogene activation or inactivation of tumor suppressor genes. In addition to this beneficial effect, senescence has been deemed to have age-associated deleterious effects because, apparently, senescence not only recapitulates aging and therefore loss of function and tissue regeneration capacity, but can also induce preneoplastic changes in adjacent stromal cells, provoke degenerative diseases or induce the production of tumor cell growth promoting factors. For that reason, senescence has become an attractive therapeutic target against cancer. This paper reviews some of the latest findings on the role of senescence in the malignant progression and analyzes them in relation to the concept of antagonistic pleiotropism, as well as its possible use as a therapeutic target against cancer.


La relación entre senescencia y transformación maligna ha sido objeto de particular atención, debido a una aparente dualidad de funciones, en la que la senescencia participaría tanto en la inducción como en la inhibición de la malignidad. El objetivo del trabajo fue revisar algunos de los hallazgos más recientes sobre el papel de la senescencia en la progresión maligna y analizarlos a la luz del concepto de la pleiotropía antagónica y de su posible utilización como blanco terapéutico contra el cáncer. Se considera a la senescencia como un mecanismo supresor tumoral, debido al efecto protector contra el cáncer que ejerce en organismos jóvenes, en caso de activación de oncogenes o de inactivación de genes supresores tumorales. Además de este efecto beneficioso, se le han adjudicado efectos deletéreos asociados con la edad pues, en apariencia, la senescencia no sólo recapitula el envejecimiento y por tanto la pérdida de función y capacidad de regeneración tisular, sino también puede inducir cambios preneoplásicos en las células del estroma adyacente, provocar enfermedades degenerativas o inducir la secreción de factores promotores del crecimiento de células tumorales. La aparición de defectos en el programa de senescencia puede contribuir a la transformación tumoral, lo que la ha convertido en un atractivo blanco terapéutico contra el cáncer. El avance en el estudio de los aspectos biológicos de la senescencia proporcionará valiosa información para el desarrollo de nuevas estrategias terapéuticas que detengan la progresión tumoral.


Assuntos
Humanos , Senescência Celular/fisiologia , Senescência Celular/genética , Neoplasias/genética , Proteínas Supressoras de Tumor , Transformação Celular Neoplásica , Dano ao DNA , Oncogenes
15.
Invest Clin ; 51(3): 351-67, 2010 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-21305772

RESUMO

Beta-galactosidase activity reflects the rate of cellular aging in vitro. Such activity was quantified at pH 6 in ovarian epithelial cells from 28 donors without a history of cancer, by the chemoluminiscent method. The cells were serially cultured until they achieved the state of permanent growth arrest. During the exponential growth phase, all cultures showed a similar pattern of growth and low beta-galactosidase activity. However, both in the onset of decrease replicative activity, as well as in the onset of the stationary phase, there was a significant rise in the enzyme activity. Our results showed that beta-galactosidase activity can be considered as a replicative senescence marker of the ovarian surface epithelium at pH 6.


Assuntos
Senescência Celular , Células Epiteliais/enzimologia , Ovário/citologia , beta-Galactosidase/metabolismo , Adolescente , Adulto , Células Cultivadas , Células Epiteliais/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
16.
Invest Clin ; 51(4): 541-51, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21361148

RESUMO

Our objective was to determine the presence of chromosomal abnormalities in primary cultures of ovarian surface epithelial cells in women of different ages with no history of cancer. Throughout conventional cytogenetic techniques, we analyzed chromosome spreads of cultured ovarian epithelial cells from 10 donors who were 50 or more years old (B) and 16 controls between 20 and 49 years old (A), belonging to the mestizo population in Bogota DC, Colombia. Of the 26 cultures that were analyzed in passage 1, 61.5% had an abnormal chromosome complement (62.5% in A, and 60% in B). Abnormalities included polyploidies, endoduplications and monosomies. Deletions in chromosomes 3 and 11 were found in just one metaphase. None of the samples showed weaknesses or breakpoints. After transforming and applying the exact student's t-test for variance heterogeneity, we found significant differences in the frequency of metaphases, that were higher in A than in B (p=0.05), and in the frequency of polyploidies, which were higher in B than in A (p=0.044). Through the application of the Mann-Whitney test, we determined that the frequency of endoduplications was higher in A than in B (p=0.126), without reaching significant differences. There were no significant differences in the frequency of monosomies. The level of significance was set at p < or = 0.05. Taking into account that polyploidization is a marker of chromosomal instability and that the risk of cancer arising from the ovarian surface epithelium augments substantially after menopause, the increase in the frequency of age-associated polyploidies could be used as a predictor of ovarian cancer in women from an ethnically homogeneous population as the mestizo one in Bogota DC.


Assuntos
Aberrações Cromossômicas , Células Epiteliais/ultraestrutura , Ovário/citologia , Fatores Etários , Idoso , Aneuploidia , Transformação Celular Neoplásica/genética , Células Cultivadas/ultraestrutura , Suscetibilidade a Doenças , Feminino , Humanos , Cariotipagem , Metáfase , Pessoa de Meia-Idade , Índice Mitótico , Neoplasias Ovarianas/genética , Pós-Menopausa
17.
Invest. clín ; 49(4): 561-593, dic. 2008. ilus
Artigo em Espanhol | LILACS | ID: lil-518670

RESUMO

El epitelio superficial del ovario (ESO), tejido formado por una sola capa de células, está sujeto a una elevada tasa de renovación en el sitio de la ruptura provocada por la ovulación, lo que ha sido asociado con un mayor riesgo de desarrollar cáncer como consecuencia de la transformación maligna de sus células. El hallazgo de un 90% de tumores ováricos derivados del epitelio superficial, así como de mutaciones del gen p53 en la gran mayoría de ellos, constituyen la justificación para revisar la estructura y la histogénesis de dicho tejido con referencia a p53. Igualmente se consideran algunos aspectos relacionados con la estabilización de la proteína, su regulación, su participación en eventos claves como detención del ciclo celular, inducción de apoptosis, la etiología y patogénesis del cáncer ovárico epitelial y por último, algunos de los más recientes avances farmacogenéticos que utilizan a p53 como blanco terapéutico contra el cáncer.


Assuntos
Humanos , Feminino , Apoptose , Ciclo Celular , Tratamento Farmacológico , Neoplasias Ovarianas
18.
Invest Clin ; 49(4): 561-93, 2008 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-19245174

RESUMO

The ovarian surface epithelium (OSE) is a single layer of cells subject to a high rate of turnover at the site of follicular rupture at ovulation and this results in a higher risk of malignant cell transformation. Findings like cancer derived from OSE, that accounts for approximately 90% of all human ovarian malignancies and the frequent mutations of the p53 gen in most of them, are the basis for reviewing OSE structure and histogenesis related to p53, as well as some aspects associated with p53 stabilization and regulation, its involvement in key events like cell cycle arrest, induction of apoptosis, etiology and pathogenesis of epithelial ovarian cancer. Finally, this review takes into account recent farmacogeneticsadvances in order to use p53 as a target in the therapy against cancer.


Assuntos
Genes p53/fisiologia , Neoplasias Ovarianas/etiologia , Ovário , Proteína Supressora de Tumor p53/fisiologia , Diferenciação Celular/genética , Proliferação de Células , Epitélio/patologia , Feminino , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/terapia , Ovário/citologia , Ovário/metabolismo , Ovário/patologia , Proteína Supressora de Tumor p53/genética
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