ABSTRACT
BACKGROUND High-risk human papillomaviruses (HR-HPVs) are the etiological agents of cervical cancer. Among them, types 16 and 18 are the most prevalent worldwide. The HPV genome encodes three oncoproteins (E5, E6, and E7) that possess a high transformation potential in culture cells when transduced simultaneously. In the present study, we analysed how these oncoproteins cooperate to boost key cancer cell features such as uncontrolled cell proliferation, invasion potential, and cellular redox state imbalance. Oxidative stress is known to contribute to the carcinogenic process, as reactive oxygen species (ROS) constitute a potentially harmful by-product of many cellular reactions, and an efficient clearance mechanism is therefore required. Cells infected with HR-HPVs can adapt to oxidative stress conditions by upregulating the formation of endogenous antioxidants such as catalase, glutathione (GSH), and peroxiredoxin (PRX). OBJECTIVES The primary aim of this work was to study how these oncoproteins cooperate to promote the development of certain cancer cell features such as uncontrolled cell proliferation, invasion potential, and oxidative stress that are known to aid in the carcinogenic process. METHODS To perform this study, we generated three different HaCaT cell lines using retroviral transduction that stably expressed combinations of HPV-18 oncogenes that included HaCaT E5-18, HaCaT E6/E7-18, and HaCaT E5/E6/E7-18. FINDINGS Our results revealed a statistically significant increment in cell viability as measured by MTT assay, cell proliferation, and invasion assays in the cell line containing the three viral oncogenes. Additionally, we observed that cells expressing HPV-18 E5/E6/E7 exhibited a decrease in catalase activity and a significant augmentation of GSH and PRX1 levels relative to those of E5, E6/E7, and HaCaT cells. MAIN CONCLUSIONS This study demonstrates for the first time that HPV-18 E5, E6, and E7 oncoproteins can cooperate to enhance malignant transformation.
Subject(s)
Humans , Cell Transformation, Viral/genetics , Oncogene Proteins, Viral/metabolism , DNA-Binding Proteins/metabolism , Human papillomavirus 18/metabolism , Oxidation-Reduction , Gene Expression Regulation, Neoplastic , Cell Survival , Cell Line, Tumor/virology , Cell ProliferationABSTRACT
Introducción. Existen evidencias de la asociación de determinantes sociales con la salud infantil. Objetivo. Identificar características sociodemográficas asociadas a desigualdades en la salud infantil y evaluar el efecto acumulado sobre la salud de factores de riesgo basados en estas características. Población y métodos. Evaluamos niños de 4-13 años, de Bariloche, entre junio de 2008 y mayo de 2009. Características sociodemográficas consideradas: nivel socioeconómico, educación materna, embarazo adolescente, cobertura médica, inseguridad y hábitos familiares. Valoramos la percepción parental de la salud física y socioemocional, el estado nutricional y la salud bucal en relación con dichas características y con la acumulación de factores de riesgo. Utilizamos encuesta, antropometría y examen bucal. Resultados. Participaron 180 escolares. El nivel educativo materno se asoció con la salud física, socioemocional y bucal del niño. El porcentaje de niños con piezas faltantes o caries fue 77% entre aquellos cuyas madres, como máximo, habían completado el primario, comparado con 13% entre aquellos cuyas madres habían completado estudios terciarios/universitarios. La posibilidad de percepción de salud física y socioemocional no óptima aumentó con cada factor de riesgo 1,8 y 1,4 veces, respectivamente, y la posibilidad de caries o piezas faltantes se duplicó con cada factor de riesgo adicional. El 27,3% de los escolares presentó sobrepeso y el 8,7%, obesidad, y no se encontró asociación con características sociodemográficas. Conclusiones. El bajo nivel socioeconómico familiar y educativo materno se asoció con una mayor prevalencia de resultados de salud desfavorables. Múltiples factores de riesgo tienen un efecto acumulado sobre la percepción parental de la salud física y socioemocional y la salud bucal.
Introduction. There is evidence of an association between social determinants and child health. Objective. To identify sociodemographic characteristics related to child health inequalities and to analize the cumulative effect on health of risk factors based on these characteristics. Population and Methods. We evaluated 4-13 year-old children in Bariloche between June 2008 and May 2009. The following sociodemographic characteristics were taken into account: socioeconomic level, maternal education, adolescent pregnancy, medical coverage, unsafeness, and family habits. We assessed parental perception of physical, and social and emotional health, nutritional status and oral health in relation to these characteristics and the accumulation of risk factors. We used survey, anthropometry and oral examination. Results. One hundred and eighty students participated. The level of maternal education was associated with the child's physical, social and emotional, and oral health. The percentage of children with missing teeth or cavities reached 77% among those whose mothers had, at most, completed primary school, compared to 13% among those whose mothers had completed tertiary school or university. The possibility of perceiving a non-optimal physical, and social and emotional health increased 1.8 and 1.4 times with each risk factor, respectively, and the possibility of having missing teeth or cavities was twice as much with each additional risk factor. Overweight and obesity was observed in 27.3% and 8.7% of students, respectively, and no relationship was found with sociodemographic characteristics. Conclusions. A low family socioeconomic level and a low maternal education level were associated with a higher prevalence of unfavorable health outcomes. Multiple risk factors have an cumulative effect on parental perception of physical, social and emotional, and oral health.
Subject(s)
Humans , Cell Transformation, Viral/genetics , Gene Expression Profiling , Transcriptome , Antigens, Surface/genetics , Antigens, Surface/metabolism , Cell Line, Transformed , Cell Proliferation , Cells, Cultured , Flow Cytometry , Gene Expression , Genes, Viral , Genotype , /genetics , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/virology , Transcription, Genetic , Virus LatencyABSTRACT
El cáncer es un proceso multifactorial y con múltiples etapas. Los protooncogenes, antioncogenes y virus oncogénicos están involucrados en el desarrollo de diversas neoplasias. La expresión alterada de los protooncogenes (por mutaciones, rearreglos o amplificaciones), así como la cooperación entre ellos puede llevar a la célula a una estado transformado. Los genes p53 y RB codifican para dos proteínas antioncogénicas que regulan las decisiones celulares de proliferación o diferenciación. La ausencia de RB (pérdida de ambos alelos) lleva a la liberación de factores de transcripción. p53 en su forma mutada, favorece el crecimiento celular. El cáncer cervicouterino ejemplifica claramente la intervención de este tipo de factores en su desarrollo. Los papilomavirus humanos genitales (PVH) estan implicados en su etiología como iniciadores de la proliferación celular. La inactivación de las proteínas antioncogénicas p53 y p105 RB porparte de los oncogenes virales E6 y E7, respectivamente, mantiene el estado de divición celular continua. Adicionalmente, la participación de ooncogenes expresados en forma alterada (c-myc) y otros cofactores contribuyen a modificar los periodos de latencia y la gravedad de la enfermedad