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1.
Cancer Med ; 12(4): 4306-4320, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36329628

RESUMEN

BACKGROUND: The role of ERG-status molecular subtyping in prognosis of prostate cancer (PCa) is still under debate. In this study, we identified differentially expressed genes (DEGs) according to ERG-status to explore their enriched pathways and implications in prognosis in Hispanic/Latino PCa patients. METHODS: RNA from 78 Hispanic PCa tissues from radical prostatectomies (RP) were used for RNA-sequencing. ERGhigh /ERGlow tumor groups were determined based on the 1.5-fold change median expression in non-tumor samples. DEGs with a False Discovery Rate (FDR) < 0.01 and a fold change >2 were identified between ERGhigh and ERGlow tumors and submitted to enrichment analysis in MetaCore. Survival and association analyses were performed to evaluate biochemical recurrence (BCR)-free survival. RESULTS: The identification of 150 DEGs between ERGhigh and ERGlow tumors revealed clustering of most of the non-BCR cases (60%) into de ERGhigh group and most of the BCR cases (60.8%) in ERGlow group. Kaplan-Meier survival curves showed a worst BCR-free survival for ERGlow patients, and a significant reduced risk of BCR was observed for ERGhigh cases (OR = 0.29 (95%CI, 0.10-0.8)). Enrichment pathway analysis identified metabolic-related pathways, such as the renin-angiotensin system and angiotensin maturation system, the linoleic acid metabolism, and polyamines metabolism in these ERG groups. CONCLUSIONS: ERGlow tumor cases were associated with poor BCR-free survival in our Hispanic/Latino patients, with metabolism-related pathways altered in the BCR progression. IMPACT: Our findings suggest the need to dissect the role of diet, metabolism, and lifestyle as risk factors for more aggressive PCa subtypes.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Próstata , Masculino , Humanos , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/metabolismo , Pronóstico , Prostatectomía , Redes y Vías Metabólicas , ARN/metabolismo , Recurrencia Local de Neoplasia/genética , Regulador Transcripcional ERG/genética
2.
Cancer Rep (Hoboken) ; 6(2): e1728, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36199157

RESUMEN

BACKGROUND: The prognostic relevance of prostate cancer (PCa) molecular subtypes remains controversial, given the presence of multiple foci with the possibility of different subtypes in the same patient. AIM: To determine the clonal origin of heterogeneity in PCa and its association with disease progression, SPOP, ERG(+), EZH2, NKX3.1, and SPINK-1 subtypes were analyzed. METHODS: A total of 103 samples from 20 PCa patients were analyzed; foci of adjacent non-tumor prostate tissue, HGPIN, GL3, GL4, GL5, and LN were examined to determine the presence of the TMPRSS2-ERG fusion and ERG, EZH2, NKX3.1, and SPINK-1 expression levels, using RT-PCR. Mutations in exons 6 and 7 of the SPOP gene were determined by sequencing. The presence of subtypes and molecular patterns were identified by combining all subtypes analyzed. To establish the clonal origin of multifocal PCa, molecular concordance between different foci of the same patient was determined. Association of these subtypes with histopathological groups and time to biochemical recurrence (BCR) was assessed. RESULTS: No mutation was found in SPOP in any sample. The ERG(+) subtype was the most frequent. The molecular pattern containing all four PCa subtypes was only detected in 3 samples (4%), all LN, but it was the most frequent (40%) in patients. Molecular discordance was the predominant status (55%) when all analyzed molecular characteristics were considered. It was possible to find all subtypes, starting as a preneoplastic lesion, and all but one LN molecular subtype were ERG(+) and NKX3.1 subtypes. Only the expression of the NKX3.1 gene was significantly different among the histopathological groups. No association was found between BCR time in patients and molecular subtypes or molecular concordance or between clinicopathological characteristics and molecular subtypes of ERG, EZH2, and SPINK-1. CONCLUSION: The predominance of molecular discordance in prostatic foci per patient, which reflects the multifocal origin of PCa foci, highlights the importance of analyzing multiple samples to establish the prognostic and therapeutic relevance of molecular subtypes in a patient. All the subtypes analyzed here are of early onset, starting from preneoplastic lesions. NKX3.1 gene expression is the only molecular characteristic that shows a progression pattern by sample.


Asunto(s)
Neoplasias de la Próstata , Inhibidor de Tripsina Pancreática de Kazal , Masculino , Humanos , Proteínas de Fusión Oncogénica/genética , Neoplasias de la Próstata/patología , Factores de Transcripción/genética , Progresión de la Enfermedad , Regulador Transcripcional ERG , Proteínas Nucleares , Proteínas Represoras , Proteína Potenciadora del Homólogo Zeste 2
3.
J Cancer Educ ; 38(3): 1000-1009, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36183277

RESUMEN

In Colombia, prostate cancer (PCa) is the most common cancer for incidence and mortality in men, which turns it into a public health problem. For high-risk communities to better understand the usefulness of basic research about PCa, a strategy of social appropriation of knowledge (SAK) in science and cancer was designed and implemented. A pedagogical activity and two tests (a pre-test and a post-test) were applied to middle education students in four schools in three Colombian cities to identify previous knowledge of biology concepts and cancer perceptions. As for biology concepts, there was a statistically significant increase (p < 0.01) in the total results of all questions in the post-test, especially in items related to the structure of DNA, differences between RNA and DNA, and codon. Similarly, better success rates were observed in questions about replication and mutation, and a statistically significant improvement related to the definition of cancer, cancer prevention, and its association with culture or ethnicity (p < 0.01). The results of the open question show what students learned about or were interested in the most, as evidence of the exchange of knowledge in those cities and the social appropriation of knowledge about PCa in Colombia. These findings show that this type of intervention, in diverse social contexts, is essential to improve understanding and perceptions that link school and scientific knowledge to a real problem, such as health and, in this case, cancer.


Asunto(s)
Neoplasias de la Próstata , Estudiantes , Masculino , Humanos , Colombia , Ciudades , Instituciones Académicas , Neoplasias de la Próstata/prevención & control , Conocimientos, Actitudes y Práctica en Salud
4.
Cancer Diagn Progn ; 2(5): 576-584, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36060016

RESUMEN

BACKGROUND/AIM: Although some mutations of KRAS proto-oncogene, GTPase (KRAS) have been associated with the prognosis and therapeutic management of colorectal cancer (CRC), the epigenetic mechanisms (DNA methylation and microRNA expression) that regulate wild-type KRAS expression in patients with CRC are poorly known. The aim of this study was to establish whether there is a relationship between the expression of the wild-type KRAS gene, the methylation status of its distal promoter, and miR-143 and miR-18a-3p levels in samples of sporadic CRC. PATIENTS AND METHODS: A total of 51 cases of sporadic CRC with wild-type KRAS were analyzed. The expression levels of KRAS mRNA, miR-18a-3p, miR-143, and KRAS protein, as well as methylation in the distal promoter of the KRAS gene were evaluated. RESULTS: In the analyzed cases, KRAS mRNA expression was detected in 51.1%; wild-type KRAS protein was found in the membrane in 31.4% and in the cytoplasm in 98% of cases. An inverse relationship of marginal significance was observed between miR-18a-3p and KRAS protein expression in the cytoplasm (odds ratio=0.14, 95% confidence interval=0.012-1.092; p=0.08). The methylation status of the distal promoter of KRAS at four CpG islands was analyzed in 30 cases (58.8%): partial methylation of the four CpG islands evaluated was observed in two cases (6.7%). In these cases, KRAS protein expression was not evidenced at the membrane level; miR-18a-3p expression was not detected either but high expression of miR-143 was observed. CONCLUSION: No association was found between the expression levels of KRAS mRNA, miR-18a-3p, miR-143 and methylation status. Methylation status was detected with low frequency, thus being the first report of methylation in wild-type KRAS.

5.
Rev. colomb. cancerol ; 25(3): 125-139, jul.-set. 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1376839

RESUMEN

Abstract Proteasomal degradation is an essential regulatory mechanism for cellular homeostasis maintenance. The speckle-type POZ adaptor protein (SPOP) is part of the ubiquitin ligase E3 cullin-3 RING-box1 complex, responsible for the ubiquitination and proteasomal degradation of biomolecules involved in cell cycle control, proliferation, response to DNA damage, epigenetic control, and hormone signaling, among others. Changes in SPOP have been associated with the development of different types of cancer, since it can act as a tumor suppressor mainly in prostate, breast, colorectal, lung cancer and liver cancer, due to point mutations and/or reduced expression, or as an oncogene in kidney cancer by protein overexpression. In endometrial cancer it has a dual role, since it can act as a tumor suppressor or as an oncogene. SPOP is a potential prognostic biomarker and a promising therapeutic target.


Resumen La degradación proteosómica es un mecanismo de regulación esencial para el mantenimiento de la homeostasis celular. La proteína adaptadora Speckle-type POZ (SPOP) hace parte del complejo ubiquitin ligasa E3 cullin-3 RING-box1, encargado de la ubiquitinación y degradación proteosomal de biomoléculas involucradas en el control del ciclo celular, proliferación, respuesta al daño de ADN, control epigenético, señalización hormonal, entre otros. Las alteraciones en SPOP han sido asociadas al desarrollo de diferentes tipos de cáncer, ya que puede actuar como supresor tumoral principalmente en cáncer de próstata, mama, colorrectal y pulmón, debido a mutaciones puntuales y/o expresión reducida o como oncogén en cáncer riñón por sobreexpresión de la proteína. En cáncer endometrial tiene un rol dual, ya que puede actuar como supresor tumoral o como oncogén. SPOP es considerado como un potencial biomarcador pronóstico y un objetivo terapéutico prometedor.


Asunto(s)
Humanos , Oncogenes , Biomarcadores , Ubiquitina-Proteína Ligasas , Epigenómica , Neoplasias , Pronóstico , Daño del ADN , Ciclo Celular , Proteínas Cullin , Puntos de Control del Ciclo Celular , Ligasas
6.
Oncol Lett ; 21(5): 376, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33777200

RESUMEN

Prostate cancer (PCa) is characterized as being histologically and molecularly heterogeneous; however, this is not only incorrect among individuals, but also at the multiple foci level, which originates in the prostate gland itself. The reasons for such heterogeneity have not been fully elucidated; however, understanding these may be crucial in determining the course of the disease. PCa is characterized by a complex network of chromosomal rearrangements, which simultaneously deregulate multiple genes; this could explain the appearance of exclusive events associated with molecular subtypes, which have been extensively investigated to establish clinical management and the development of therapies targeted to this type of cancer. From a clinical aspect, the prognosis of the patient has focused on the characteristics of the index lesion (the largest focus in PCa); however, a significant percentage of patients (11%) also exhibit an aggressive secondary foci, which may determine the prognosis of the disease, and could be the determining factor of why, in different studies, the classification of the subtypes does not have an association with prognosis. Due to the aforementioned reasons, the analysis of molecular subtypes in several foci, from the same individual could assist in determining the association between clinical evolution and management of patients with PCa. Castration-resistant PCa (CRPC) has the worst prognosis and develops following androgen ablation therapy. Currently, there are two models to explain the development of CRPC: i) The selection model and ii) the adaptation model; both of which, have been found to include alterations described in the molecular subtypes, such as Enhancer of zeste 2 polycomb repressive complex 2 subunit overexpression, isocitrate dehydrogenase (NAPD+)1 and forkhead box A1 mutations, suggesting that the presence of specific molecular alterations could predict the development of CRPC. This type of analysis could lead to a biological understanding of PCa, to develop personalized medicine strategies, which could improve the response to treatment thus, avoiding the development of resistance. Therefore, the present review discusses the primary molecular factors, to which variable heterogeneity in PCa progress has been attributed.

7.
Mol Clin Oncol ; 11(2): 201-207, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31316774

RESUMEN

Colorectal cancer (CRC) is one of the prominent causes of cancer related deaths because, in part, there is not an early, non-invasive, effective detection strategy. Circulating microRNAs (miRNAs) have been proposed as potential non-invasive biomarkers for CRC. In this study, we evaluated the miRNA profile in sixteen CRC tissues by Next-Generation-Sequencing and compared the circulating expression levels of 22 miRNAs among 45 CRC, 14 hyperplastic polyps, 11 advanced adenoma patients and 45 control subjects, by reverse transcription-quantitative PCR, to search for miRNAs which could be potential biomarkers. In total, nine of them represented 70% of total read counts (miR-10a-5p, miR-192-5p, miR-10b-5p, miR-22-3p, miR-26a-5p, miR-148a-3p, miR-181a-5p, miR-92a-3p and miR-143-5p). In silico analysis found eight candidates to mature miRNAs. With respect to circulating miRNA, we found higher serum expression levels of miR-143-3p, miR-141-3p and miR-200c-3p in the CRC and adenoma groups compared with controls (P<0.002), and we also found significant higher levels of miR-141-3p and miR-200c-3p in serum of adenoma patients compared with the CRC group. In conclusion, the measurement of miRNAs in the blood could complement current screening methods for CRC and might provide new insights into mechanisms of tumorigenesis. miR-143-3p, miR-141-3p and miR-200c-3p could be interesting miRNAs to study as potential biomarkers for CRC.

8.
Rev. colomb. cancerol ; 20(4): 167-174, oct.-dic. 2016. ilus, tab
Artículo en Español | LILACS | ID: biblio-959868

RESUMEN

Introducción: En 2007 el Instituto Nacional de Cancerología (INC) realizó un ejercicio para la definición de ocho líneas de investigación que abarcan temáticas para poder enfocar la investigaciónen cáncer en Colombia y poder realizar una priorización acertada de las temáticas a investigar. Objetivo: Evaluar la productividad en términos de artículos científicos generados y la formación de recurso humano de cada una de las líneas de investigación. Métodos: Se realizó la búsqueda de grupos de investigación con producción en cáncer en la plataforma ScienTI del Departamento Administrativo de Ciencia, Tecnología e Innovación de Colombia (Colciencias), con fecha de corte a julio de 2013. Estos grupos fueron clasificados en las líneas de investigación correspondientes según el contenido de los productos evaluados y fueron cuantificados. Resultados: La línea de Biología del cáncer fue la que mayor cantidad de productos generó, tanto en números absolutos como en cocientes ajustados por número de grupos vinculados y evidenciando que es la más consolidada. La línea de Diagnóstico y tratamiento, aunque registró la mayor cantidad de grupos vinculados, tuvo una productividad ajustada por grupo inferior a la de otras líneas. Las dos líneas más rezagadas fueron las líneas de Servicios oncológicos y de Actuar político y cáncer. Conclusiones: El hecho de que las líneas tengan tantas diferencias en su proceso de consolidación en Colombia supone que existen líneas que requieren del diseño y la implementación de estrategias que las fortalezcan, mediante acciones que involucren la gestión del conocimiento y la tecnología, y la formación y el desarrollo del talento humano.


Introduction: In 2007, the Instituto Nacional de Cancerología (INC) of Colombia carried out an exercise by defining eight lines for research, which included topics for focusing on cancer research in Colombia, as well as setting out to prioritise certain topics to investigate. Objective: To evaluate the productivity of these cancer research lines in terms of the training of human resources and the quantity of published scientific articles. Methods: After defining the key words, a search was made in the ScienTI platform of the Administrative Department of Science, Technology and Innovation of Colombia (Colciencias), up to a cut-off date of July 2013, in order for identify scientific productivity of groups, institutions, projects, and products for each cancer research line. Results: Cancer Biology was the most consolidated line with the most researchers, groups, projects and products, both in absolute numbers as well in ratios adjusted for number of groups involved. Diagnosis and treatment, although it registered the highest number of groups involved, it had an adjusted productivity lower than other lines. The two least developed lines were Oncology services and updating cancer policy. Conclusion: The fact that research lines have so many differences in their consolidation process in Colombia means that there are some lines need designs and strategies that may strengthen them. This requires actions involving the management of knowledge and technology, as well as the training and development of human resources.


Asunto(s)
Humanos , Investigación , Grupos de Investigación , Gestión del Conocimiento , Neoplasias , Red Internacional de Fuentes de Información y Conocimiento para la Gestión de la Ciencia, Tecnología e Innovación , Proyectos , Políticas , Oncología Médica
9.
Rev. colomb. cancerol ; 19(4): 229-238, oct.-dic, 2015. ilus, tab
Artículo en Inglés | LILACS | ID: lil-769099

RESUMEN

Cancer is currently recognized as a major cause of mortality worldwide, and, as such, has a significant impact on public health. Successful early detection strategies are linked to a decrease in mortality; however, because they are invasive, highly complex, and have low specificity, their application has been limited. MicroRNAs (miRNAs) are short, non-coding RNA sequences capable of regulating gene expression. Molecular mechanisms of miRNAs in cancer are not fully understood, but specific patterns of miRNAs expression have been associated with many tumour types. MicroRNAs as biomarkers can help to identify tumour origin and allow their early detection. They can also be used to monitor progression and therapeutic response. The presence and stability of miRNAs in blood, as circulating miRNAs, are major factors that contribute to their use as potential biomarkers in a clinical context. The aim of this article is to present a review of miRNAs as circulating biomarkers in cancer.


El cáncer es reconocido como una de las principales causas de mortalidad a nivel mundial teniendo así un impacto significativo en la salud pública. Una disminución en la mortalidad por esta enfermedad se ha asociado con estrategias exitosas de detección temprana; sin embargo, debido a que estas son invasivas, altamente complejas y registran baja especificidad, su aplicación ha sido limitada. Los microRNA (miRNA) son RNA no codificantes de secuencias cortas, capaces de regular la expresión génica. Los mecanismos moleculares de los miRNA en cáncer aún no están totalmente clarificados, pero patrones específicos de la expresión de estos han sido asociados con muchos tipos de tumores. Los miRNA como biomarcadores pueden ayudar a identificar el origen de un tumor, realizar detección temprana, predecir la progresión de la enfermedad y la respuesta al tratamiento. La presencia y estabilidad de los miRNA en la sangre, como miRNA circulantes, son los principales factores que contribuyen a su uso potencial como biomarcadores en un contexto clínico. El objetivo de este artículo es realizar una revisión sobre los miRNA circulantes en cáncer.


Asunto(s)
Humanos , Biomarcadores de Tumor , Diagnóstico , ARN no Traducido , ARN , Biomarcadores , Sensibilidad y Especificidad , Progresión de la Enfermedad
10.
Rev. colomb. cancerol ; 19(1): 39-46, ene.-mar. 2015. ilus, tab
Artículo en Español | LILACS | ID: lil-765552

RESUMEN

Introducción: La investigación en cáncer debe generar conocimiento que contribuya al control del cáncer y a orientar mejor la investigación. Objetivo: Caracterizar la investigación en cáncer en Colombia realizada entre 2000 y 2010, determinando el número de personas, grupos e instituciones que estudian el cáncer e identificar su producción bibliográfica y proyectos de investigación realizados. Métodos: Se realizó un estudio descriptivo para el periodo 2000-2010, de índole bibliométrico mediante consulta a las plataformas Scien TI y SIGP de Colciencias, para identificar investigadores, grupos de investigación, instituciones y proyectos. Para determinar la producción bibliográfica asociada, se consultaron las bases de datos Web of Science, Scopus y PubMed. Resultados: Se identificaron 1.982 personas asociadas a 546 grupos, 129 instituciones avaladoras y 2.481 productos de investigación en cáncer. Los tipos de cáncer más estudiados correspondieron a: cuello del útero, estómago, mama, leucemias e hígado. Las líneas de investigación más desarrolladas fueron diagnóstico, tratamiento y biología del cáncer. Los tipos de publicación más frecuentes fueron pruebas diagnósticas, series de casos y los artículos de opinión. El promedio del factor de impacto de las revistas donde se hicieron publicaciones fue de 2,53. Discusión: A pesar del incremento observado en las capacidades nacionales para la investigación del cáncer, se identificaron limitaciones en la visibilidad de los productos generados y en la investigación en determinados tipos de cáncer que tienen alta incidencia en el territorio colombiano.


Introduction: Cancer research must generate knowledge that permits the improvement of the different components of cancer control. The information about research topics, resources and capabilities in this country will enable adjustments to be made aimed at achieving a greater impact on cancer control and management. Purpose: To describe the general features of cancer research in Colombia between 2000 and 2010, in terms of the number of individuals, groups and institutions developing research in cancer, and to identify the cancer projects developed and their associated bibliographic production. Methods: The Colciencias platforms were consulted in order to identify cancer-related researchers, research groups, institutions and projects. A search was conducted in the databases Web of Science, Scopus and PubMed to determine the associated bibliographic production. Findings: A total of 1,982 individuals, 546 groups, 129 institutions, and 2,481 cancer research products were identified, with the most frequently studied cancers being cervix, stomach, breast, leukemia, and liver. The most common developed cancer research areas were diagnosis and treatment, and cancer biology. The most common publication types were diagnostic tests, case series, and review articles. The average publication impact factor was 2.53. Discussion: Despite the increase in cancer research capacity observed in recent years in Colombia, limitations in the visibility of the bibliographic production were observed, as well as a lack of research in some common cancers.


Asunto(s)
Humanos , Investigación , Colombia , Grupos de Investigación , Neoplasias , Publicaciones Periódicas como Asunto , Proyectos de Investigación , Organizaciones , Pruebas Diagnósticas de Rutina , Equipos y Suministros , Proyectos , Recursos en Salud
11.
Biomedica ; 33(1): 53-61, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23715307

RESUMEN

INTRODUCTION: Retinoblastoma is a childhood cancer of the retina originated by altered or null retinoblastoma protein (pRb) expression. Genetic alterations in both RB1 alleles in the retinal cells are required for the development of retinoblastoma. In the sporadic form, non-hereditary RB1 gene mutations take place in a single retinoblast cell, and are therefore only present in tumor DNA (somatic mutations). Sporadic retinoblastoma is primarily unilateral, lacks family history and has no risk of transmission to descendants. Genetic tests for detection of RB1 mutation has improved the identification of carriers and facilitated accurate genetic counseling. OBJECTIVE: To identify mutations in the RB1 gene in Colombian patients with sporadic retinoblastoma by PCR-SSCP followed by sequence. MATERIALS AND METHODS: Four patients with sporadic retinoblastoma were analyzed by PCR-SSCP, followed by DNA sequencing to identify variations in the RB1 gene. RESULTS: We identified five variations in RB1 gene: three new mutations (one germline and two somatic mutations), one new polymorphism and one already reported somatic mutation. Four mutations were found in three patients with unilateral retinoblastoma and one mutation was found in a patient with bilateral retinoblastoma. One of these was a germline mutation in a sporadic unilateral retinoblastoma that was not present in the parents or three siblings analyzed. CONCLUSIONS: Our results emphasize the importance of identifying mutations for genetic counseling and clinical management of sporadic retinoblastoma patients. Description of a new RB1 gene variant is interesting since there have been a small number of polymorphisms reported for this gene.


Asunto(s)
Neoplasias del Ojo/genética , Genes de Retinoblastoma , Mutación , Retinoblastoma/genética , Preescolar , Análisis Mutacional de ADN , ADN de Neoplasias/análisis , ADN de Neoplasias/sangre , ADN de Neoplasias/genética , Neoplasias del Ojo/sangre , Femenino , Mutación del Sistema de Lectura , Mutación de Línea Germinal , Humanos , Lactante , Masculino , Neoplasias Primarias Múltiples/sangre , Neoplasias Primarias Múltiples/genética , Linaje , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Retinoblastoma/sangre , Análisis de Secuencia de ADN
12.
Biomédica (Bogotá) ; 33(1): 53-61, ene.-mar. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-675132

RESUMEN

Introduction. Retinoblastoma is a childhood cancer of the retina originated by altered or null retinoblastoma protein (pRb) expression. Genetic alterations in both RB1 alleles in the retinal cells are required for the development of retinoblastoma. In the sporadic form, non-hereditary RB1 gene mutations take place in a single retinoblast cell, and are therefore only present in tumor DNA (somatic mutations). Sporadic retinoblastoma is primarily unilateral, lacks family history and has no risk of transmission to descendants. Genetic tests for detection of RB1 mutation has improved the identification of carriers and facilitated accurate genetic counseling. Objective. To identify mutations in the RB1 gene in Colombian patients with sporadic retinoblastoma by PCR-SSCP followed by sequence. Materials and methods. Four patients with sporadic retinoblastoma were analyzed by PCR-SSCP, followed by DNA sequencing to identify variations in the RB1 gene. Results. We identified five variations in RB1 gene: three new mutations (one germline and two somatic mutations), one new polymorphism and one already reported somatic mutation. Four mutations were found in three patients with unilateral retinoblastoma and one mutation was found in a patient with bilateral retinoblastoma. One of these was a germline mutation in a sporadic unilateral retinoblastoma that was not present in the parents or three siblings analyzed. Conclusions. Our results emphasize the importance of identifying mutations for genetic counseling and clinical management of sporadic retinoblastoma patients. Description of a new RB1 gene variant is interesting since there have been a small number of polymorphisms reported for this gene.


Introducción. El retinoblastoma es un cáncer pediátrico de la retina originado por la expresión alterada o ausente de la proteína del retinoblastoma (pRb). Se requiere la alteración genética de ambos alelos RB1 en las células de la retina para el desarrollo del retinoblastoma. En la forma esporádica, las mutaciones no hereditarias del gen RB1 ocurren en un solo retinoblasto y están presentes sólo en el ADN del tumor (mutaciones somáticas). El retinoblastoma esporádico es generalmente unilateral, no tiene historia familiar y no tiene riesgo de transmisión a la descendencia. Las pruebas genéticas para la detección de mutaciones en RB1 han mejorado la identificación de portadores y han facilitado la precisión de la asesoría genética. Objetivo. Detectar mutaciones en el gen RB1 en pacientes colombianos con retinoblastoma esporádico mediante PCR-SSCP seguido de secuenciación. Materiales y métodos. Se analizaron cuatro pacientes con retinoblastoma esporádico para la detección de variaciones en el gen RB1 mediante PCR-SSCP, seguida de secuenciación. Resultados. Se identificaron cinco variaciones del gen RB1 : tres mutaciones nuevas (una de línea germinal y dos somáticas), un polimorfismo nuevo y una mutación somática ya reportada. Las cuatro mutaciones se encontraron en tres pacientes con retinoblastoma unilateral y uno con bilateral. La mutación germinal se detectó en un paciente con compromiso unilateral y no se encontró en los padres ni en los tres hermanos analizados. Conclusión. Estos resultados enfatizan la importancia, para asesoría genética y manejo clínico, de identificar mutaciones del gen RB1 en pacientes con retinoblastoma esporádico. La descripción de una nueva variante en RB1 es interesante, dado el muy bajo número de polimorfismos reportados para este gen.


Asunto(s)
Preescolar , Femenino , Humanos , Lactante , Masculino , Neoplasias del Ojo/genética , Genes de Retinoblastoma , Mutación , Retinoblastoma/genética , Análisis Mutacional de ADN , ADN de Neoplasias/análisis , ADN de Neoplasias/sangre , ADN de Neoplasias/genética , Neoplasias del Ojo/sangre , Mutación del Sistema de Lectura , Mutación de Línea Germinal , Neoplasias Primarias Múltiples/sangre , Neoplasias Primarias Múltiples/genética , Linaje , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Retinoblastoma/sangre , Análisis de Secuencia de ADN
13.
Pathobiology ; 79(2): 72-83, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22213066

RESUMEN

Although high-risk human papillomaviruses (HPVs) are an important risk factor in the etiopathogenesis of cervical cancer, increasing evidence suggests that the ability to avoid immune surveillance seems to be linked to the transforming potential of HPV and a rapid progression to cancer. In other cancer models, IL-10 contributes to impair anti-tumor immune response either by downregulating human leukocyte antigen Class I (HLA-I) expression or by increasing HLA-G expression. To comprehend how these alterations could contribute to evasion of immune surveillance in cervical cancer, we analyzed HLA-I, HLA-G and IL-10 expressions by immunohistochemistry in 63 biopsies from patients with cervical intraepithelial neoplasia III (CIN-III) and cervical cancer. Immunohistochemistry showed absent or weak HLA-I expression in 50/59 cases. In these cases, a high percentage had loss of heterozygosis. IL-10 and HLA-G expression were observed in 46.6 and 27.6% of cases, respectively. Concurrent upregulation of IL-10 was found in 87.5% of HLA-G positive cases (p = 0.000). Similarly, a significant association between IL-10 expression and HLA-I downregulation was found (p = 0.028). Finally, we observed higher HLA-G expression in patients with HLA-I downregulation than in those with normal HLA-I expression (p = 0.004). Our results suggest that, in cervical cancer, the IL-10 expression may induce an immunosuppressive environment by upregulating HLA-G expression and downregulating HLA class I expression.


Asunto(s)
Antígenos HLA-G/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Interleucina-10/metabolismo , Displasia del Cuello del Útero/inmunología , Neoplasias del Cuello Uterino/inmunología , Adulto , Femenino , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virología
14.
Rev. cienc. salud (Bogotá) ; 7(2): 47-66, ago. 2009. ilus, tab
Artículo en Español | LILACS, COLNAL | ID: lil-635957

RESUMEN

La vía de señalización de la fosfatidilinositol- 3-kinasa (PI3K) es crucial en numerosos aspectos del crecimiento y la supervivencia celular. Esta vía es estimulada fisiológicamente como consecuencia de muchos factores de crecimiento y factores reguladores. Varias alteraciones genéticas como amplificación, mutación y rearreglos cromosómicos pueden comprometer la vía PI3K, generando su activación permanente. En diferentes tipos de cáncer se han encontrado evidencias de estas modificaciones genéticas deletéreas. La activación anormal de la vía PI3K resulta en alteración de los mecanismos de control del crecimiento y la supervivencia celular, lo que favorece el crecimiento competitivo, la capacidad metastasica y, frecuentemente, una mayor resistencia a los tratamientos. El objetivo de este articulo es revisar los aspectos relacionados con el funcionamiento de la vía de señalización PI3K/ Akt y su rol dentro del proceso de carcinogénesis en los seres humanos.


The signaling pathway of phosphatidylinositol 3-kinase (PI3K) is critical in many aspects of growth and cell survival. The path of PI3K is stimulated physiologically as a result of many growth factors and regulatory factors. Several genetic alterations such as amplification, mutation and chromosomal arrangements may compromise the PI3K pathway, generating permanent activation in different cancer types have found evidence of these deleterious genetic modifications. Abnormal activation of the PI3K pathway results in alteration of the control mechanisms of growth and cell survival, which favors the competitive growth, and frequently metastatic capacity, greater resistance to treatment. The aim of this paper is to review matters relating to the operation of the PI3K/Akt signaling pathway and its role in the process of carcinogenesis in humans.


Asunto(s)
Humanos , Fosfatidilinositol 3-Quinasa , Fosfatidilinositoles , Péptidos y Proteínas de Señalización Intercelular , Neoplasias
15.
Growth Horm IGF Res ; 17(6): 492-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17709267

RESUMEN

BACKGROUND: There is ample evidence that the insulin-like growth factors (IGF) system is involved in the development of several types of cancer. The aim of this study was to evaluate the expression levels of IGF-I, IGF-II, IGF binding protein 3 (IGFBP-3) and IGF-I receptor (IGF-IR) in exfoliated cervical cells in cervical carcinogenesis. METHODS: mRNA levels of IGF-I, IGF-II, IGFBP-3 and IGF-IR were assessed by real-time PCR in 105 cervical scrapes obtained from 16 patients diagnosed with low-grade squamous intraepithelial lesions (LSIL), 24 with high-grade SIL (HSIL), 23 with cervical cancer, and 42 from controls with normal Papanicolau (Pap) test. RESULTS: IGF-I mRNA levels were very low and no significant differences were seen between control and other groups. IGF-II mRNA levels were significantly lower in LSIL than in control group (median [arbitrary units]: 0.38 vs. 2.42, P=0.006) but its expression in HSIL and cervical cancer was similar to the one observed in controls. IGFBP-3 mRNA levels were significantly lower in cancer than in controls (median [arbitrary units]: 0.43 vs. 0.73, P=0.03). We observed a decrease in IGF-IR gene expression as the SIL degree increased (median for controls, LSIL, HSIL, and cervical carcinoma [arbitrary units]: 31.24, 9.08, 8.95, and 3.56, respectively). IGF-IR mRNA levels were significantly lower in HSIL and cervical cancer in comparison with controls (P=0.043 and P<0.001, respectively). CONCLUSIONS: The present observations suggest that a reduced expression of IGFBP-3 and IGF-IR can be associated with progression to cervical cancer; the specific role played by the IGF-IR in this process remains unclear.


Asunto(s)
Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/genética , Neoplasias de Células Escamosas/genética , Receptor IGF Tipo 1/genética , Displasia del Cuello del Útero/genética , Neoplasias del Cuello Uterino/genética , Adulto , Anciano , Femenino , Expresión Génica , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Persona de Mediana Edad , Neoplasias de Células Escamosas/química , Neoplasias de Células Escamosas/patología , ARN Mensajero/biosíntesis , Neoplasias del Cuello Uterino/química , Neoplasias del Cuello Uterino/patología , Frotis Vaginal , Displasia del Cuello del Útero/química , Displasia del Cuello del Útero/patología
16.
Biomedica ; 26(2): 258-68, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16925098

RESUMEN

INTRODUCTION: Pap smear has limitations as a screening test for cervical cancer. A marker that allows the identification of women who are at risk of developing cervical cancer would be useful for its prevention. A growing number of studies have demonstrated an association between insulin-like growth factors (IGF) serum levels and increased risk for various cancers. Objective. To assess whether circulating IGF-I, IGF-II, or IGF binding protein 3 (IGFBP-3) were associated with cervical cancer and low-grade and high-grade squamous intraepithelial lesions (LSIL and HSIL). MATERIALS AND METHODS: Serum levels of IGF-I, IGF-II and IGFBP-3 were measured by ELISA. Three groups of cases were analyzed: LSIL (n = 37), HSIL (n = 57), and cervical cancer (n = 41). For each case, two controls, matched by age, were included. Control subjects were women with normal, HPV-DNA-negative Pap smear. RESULTS: Significantly lower values of IGF-I (83.9 ng/ml versus 126.6 ng/ml, p < 0.001) and IGF-I:IGFBP-3 molar ratio (0.094 versus 0.137, p < 0.001) were observed among cancer cases, as compared to their control group. Women in the highest quartile of IGF-I and IGF-I:IGFBP-3 molar ratio were at an 80% (OR = 0.2, 95% CI [0.06-0.61]) and a 77% (OR = 0.23, 95% CI [0.07-0.73]) lower risk of cervical cancer, respectively, compared with women in the corresponding reference category. CONCLUSIONS: These data suggest that low values of IGF-I and IGF-I:IGFBP-3 molar ratio may be associated with cervical cancer.


Asunto(s)
Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor II del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Neoplasias de Células Escamosas/sangre , Neoplasias del Cuello Uterino/sangre , Adulto , Biomarcadores de Tumor/metabolismo , Estudios de Casos y Controles , Colombia , Femenino , Humanos , Neoplasias de Células Escamosas/diagnóstico , Neoplasias de Células Escamosas/patología , Oportunidad Relativa , Papillomaviridae/metabolismo , Factores de Riesgo , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/patología
17.
Rev. colomb. cancerol ; 10(2): 117-124, jun. 2006. tab, ilus, graf
Artículo en Español | LILACS | ID: lil-484477

RESUMEN

Introducción: La citología cérvico-uterina (CCU) en el método más empleado en el tamizaje de lesiones precancerosas de cuello uterino. Sin embargo, la CCU tiene una proporción importante de falsos positivos y negativos, y sólo una minoría delesiones precancerosas identificadas desemboca en cáncer de cuello uterino.Objetivo: Analizar si de los cepillados cervicales es posible extraer ADN, ARN y proteínas útiles para estudios de marcadores de carcinogénesis cervical.Métodos: Se recolectaron 281 cepillados cervicales. ADN, ARN y proteínas de las células cervicales fueron extraídos empleando Trizol. Se realizó PCR para el gen de la beta globina, para evaluar el ADN extraído y RT-PCR de GAPDH y UBC, para evaluar el ARN extraído. Mediante PCR en tiempo real se cuantificó el número de copias de UBC. Las proteínas fueron cuantificadasempleando el método del ácido biscinconínico. Resultados: Nueve muestras fueron negativas para PCR de beta globina (3,2%). Otras nueve fueron negativas para RT-PCRde GAPDH (3,2%), pero 176 fueron negativas para RT-PCR de UBC. Las 105 muestras restantes fueron positivas para UBC empleando PCR en tiempo real. Las proteínas extraídas estuvieron en el rango de 30 a 4559 [mi]g/ml, dos de las 281 muestras fueron negativas para proteínas por el método del ácido biscinconínico. Conclusión: De los cepillados cervicales se puede extraer ADN, ARN y proteínas útiles para la búsqueda de marcadoresmoleculares en cáncer de cuello uterino; sin embargo, por el tipo de muestra analizado se recupera menos ARN. El usode RT-PCR de GAPDH para evaluar la calidad del ADN complementario sintetizado puede dar falsos positivos debido a la presencia de seudogen procesado. Se recomienda el uso de otros genes constitutivos como UBC.


Introduction: Papanicolau (Pap) test is the most employed screening test for precancerous cervical lesions. However, this test has an important proportion of false positives and false negatives, only a minority of the identified lesions will progress to cancer. Objective: To evaluate the remnant of cervical scrapes after the preparation of the slide as source of DNA, RNA and proteinsfor search of molecular markers of progression of precancerous lesions.Methods: DNA, RNA and proteins were extracted from 281 cervical scrapes using Trizol. To evaluate the quality of DNA a PCR for beta globine was used, RNA quality was tested by RT-PCR of GADPH and UBC genes. Real time PCR was used to evaluate the number of RNA copies of UBC gene. The protein level was obtained by the biscinconinic acid method. Results: Nine samples were negative for beta globin PCR (3,2%), 9 samples were negative for GAPDH RT-PCR (3,2%) and 176 samples were negative by UBC RT PCR , the remnant 105 were positive for UBC in real-time PCR. The extracted proteinswere in a rank between 30 and 4559 [mi]g/mL, two of 281 samples were negative for proteins. Conclusion: From cervical scrapes is possible to extract DNA, RNA and proteins usable in biomarkers research, however therecovery of RNA is lower, this can due to some characteristics inherent to the cervical cells. The use of GAPDH as in RT PCR to evaluate DNA quality can generate false positives due to the presence of a processed pseudogen, it is recommended the use of other constitutive gen like UBC.


Asunto(s)
ADN , ARN , Neoplasias del Cuello Uterino
18.
Biomédica (Bogotá) ; 26(2): 258-268, jun. 2006. tab
Artículo en Español | LILACS | ID: lil-434533

RESUMEN

Introduction. Pap smear has limitations as a screening test for cervical cancer. A marker that allows the identification of women who are at risk of developing cervical cancer would be useful for its prevention. A growing number of studies have demonstrated an association between insulin-like growth factors (IGF) serum levels and increased risk for various cancers. Objective. To assess whether circulating IGF-I, IGF-II, or IGF binding protein 3 (IGFBP-3) were associated with cervical cancer and low-grade and high-grade squamous intraepithelial lesions (LSIL and HSIL). Materials and methods. Serum levels of IGF-I, IGF-II and IGFBP-3 were measured by ELISA. Three groups of cases were analyzed: LSIL (n = 37), HSIL (n = 57), and cervical cancer (n = 41). For each case, two controls, matched by age, were included. Control subjects were women with normal, HPV-DNA-negative Pap smear. Results. Significantly lower values of IGF-I (83.9 ng/ml versus 126.6 ng/ml, p < 0.001) and IGFI: IGFBP-3 molar ratio (0.094 versus 0.137, p < 0.001) were observed among cancer cases, as compared to their control group. Women in the highest quartile of IGF-I and IGF-I:IGFBP-3 molar ratio were at an 80 por ciento (OR = 0.2, 95 por ciento CI [0.06-0.61]) and a 77 por ciento (OR = 0.23, 95 por ciento CI [0.07- 0.73]) lower risk of cervical cancer, respectively, compared with women in the corresponding reference category. Conclusions. These data suggest that low values of IGF-I and IGF-I:IGFBP-3 molar ratio may be associated with cervical cancer.


Asunto(s)
Femenino , Factor I del Crecimiento Similar a la Insulina , Factor II del Crecimiento Similar a la Insulina , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Somatomedinas
19.
Rev. colomb. cancerol ; 8(2): 5-10, jun. 2004. tab
Artículo en Español | LILACS | ID: lil-400084

RESUMEN

Introducción: En Colombia, el cáncer de cuello uterinoes la primera causa de muerte por cáncer de mujeres en edad reproductiva. El VPH se considera un factor etiológico necesario pero no suficiente, ya que sólo una minoría de las infecciones progresan a cáncer, lo cual señala la existencia de otros cofactores requeridos para la transformación. Objetivos: Determinar factores asociados a la infección por VPH en una muestra de 218 mujeres jóvenes de Bogotá con citología normal. Materiales y métodos: La presencia de VPH en cepillado cervical se determinó mediante PCR GP5+/GP6+ y se recolectó información sobre factores asociados a infección. Resultados:La prevalencia de VPH fue de 17,4por ciento. Se encontró un mayor riesgo de infección en mujeres que han tenido más de cinco compañeros sexuales (OR=2,65; IC95por ciento 1,16-6,03)y cuya pareja no usa condón (OR=2,8;IC95por ciento 1,12-7,03). En cuanto al número de embarazos a término, se encontró que las mujeres con hijos tenían menor riesgo de infección y que el riesgo era menor entre mayor fuera el número de hijos. No se observaron asociaciones significativas con respecto a las otras variables analizadas. Coclusiones: los resultados muestran una alta prevalencia de infección por VPH en mujeres jóvenes con citología normal,similar a las reportadas en otros países. Se encontró asociación de la infección con factores sexuales como el número de compañeros sexuales, la carencia de compañero sexual habitual, la carencia de hijos y el no uso de condon


Asunto(s)
Biología Celular , Colombia , Sondas de ADN de HPV , Factores de Riesgo
20.
Rev. colomb. cancerol ; 7(4): 18-24, dic. 2003. tab, graf
Artículo en Español | LILACS | ID: lil-363830

RESUMEN

Introducción: el virus del pailoma de humano (VPH) se considera un factor etiológico necesario, pero no suficiente, en la carcinogénesis cervical. Aunque la prevalencia de esta infección es homogéa a nivel mundial, la prevalencia tipo-específica varía según la región geográfica. El objetivo de este estudio es determinar mediante secuencia directa la prevalencia tipo-específico de la infección por VPH en una muestra de mujeres jóvenes de Bogotá (Colombia) con citología normal. Materialea y métodos: se determinó la presencia de VPH en cepillados cervicales en 230 mjeres entre 18 y 36 años con citología normal mediante PCR GP5+/GP6+, y mediante la técnica SSCP y secuencia directa se realizó la tipificación de VPH. Resultados: Se encontró una prevalencia de la infección por VPH de 18,2 por ciento. Se detectaron quince tipos de VPH, de los cuales cuatro no se hubieran podido tipificar por métodos convencionales de hibridación. Los cinco tipos más prevalentes fueron el VPH16, VPH31, candidato VPH90, VPH59 y VPH18. La prevalencia de los tipos de alto riesgo fue de 10,4 por ciento y la de los de bajo riesgo, de 4,3 por ciento. de dos tipos identificados se desconoce su potencial oncogénico (HPGA6053 y L1AE9). Conclusión: la secuencia directa de ADN permitió identificar tipos VPH que no hubieran podido ser tipificados con otros métodos, en particular el candidato VPH90, el cual se encontró como el tercero más frecuente en esta muestra. Se confirmó la alta prevalencia de VPH59,tipo viral poco frecuente en regiones diferentes a Centro y Suramérica.


Asunto(s)
Humanos , Secuencia de Bases , Papillomaviridae
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