Detección de alteraciones genéticas mediante análisis citogenéticos moleculares, en una serie de casos de pacientes pediátricos con glioma en Colombia: un estudio piloto
DOI:
https://doi.org/10.35509/01239015.1112Palabras clave:
glioma, childhood cancer, in situ hybridizationResumen
Objetivo: determinar la presencia de alteraciones genéticas en vías clave de crecimiento y proliferación celular en pacientes pediátricos con gliomas en Colombia, mediante hibridación in situ fluorescente (FISH) e inmunohistoquímica.
Metodología: se realizó un estudio observacional descriptivo de una serie de casos, conformado por 50 pacientes pediátricos diagnosticados con glioma. Sobre tejido tumoral embebido en parafina remanente de los estudios diagnósticos, se emplearon microarreglos de tejido y FISH para detectar la fusión KIAA1549::BRAF, la deleción de CDKN2A, las amplificaciones de EGFR y N-Myc, y la codeleción 1p/19q. La expresión de H3K27me3 se determinó mediante inmunohistoquímica.
Resultados: la edad media al diagnóstico fue de 8,05 años, el 54 % eran niñas, el 44 % tenía gliomas de alto grado y el 56 % eran de bajo grado. El 18 % de los tumores presentaron alguna de las alteraciones genéticas, siendo la más frecuente la fusión KIAA1549::BRAF (12 %). Se detectaron alteraciones en la expresión de H3K27me3 (8 %), alteraciones en EGFR (4 %), deleción homocigota de CDKN2A (2 %) y pérdida heterocigota de 1p (2 %). No se evidenció amplificación de N-Myc en ningún caso.
Conclusiones: esta metodología resulta útil y de bajo costo para el estudio de gliomas pediátricos. Los hallazgos sugieren la presencia de un perfil genético, principalmente asociado a gliomas infantiles. Futuras investigaciones deberían explorar alteraciones características de gliomas de tipo adulto y paneles de estudio de esta naturaleza podrían incorporarse a la práctica de rutina en entornos de recursos limitados, con el fin de mejorar la clasificación de los gliomas pediátricos y su elección terapéutica.
Biografía del autor/a
Maria Fernanda Guerrero-Criollo, Morfología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
1. Morfología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
Diana Marcela Mendoza-Urbano, Patología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
2. Patología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
Julia Samanda Martínez-Rico, Morfología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
1. Morfología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
Edna Margarita Quintero-Canasto, Patología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
3. Patología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
Esteban Felipe Patiño-Calderón, Patología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
3. Patología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
Pablo Andrés Aux-Chaves, Residente de la Especialización en Radiología, Universidad Nacional de Colombia (Seccional Bogotá), Bogotá, D. C., Colombia.
4. Residente de la Especialización en Radiología, Universidad Nacional de Colombia (Seccional Bogotá), Bogotá, D. C., Colombia.
Nelson Hernando Aponte-Barrios, Hemato-Oncología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
5. Hemato-Oncología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
6. Epidemiología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
Orlando Faber Peláez-Rincón, Neurocirugía Pediátrica, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
7. Neurocirugía Pediátrica, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
Edgar Cabrera-Bernal, Hemato-Oncología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
5. Hemato-Oncología, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
8. Hemato-Oncología Pediátrica, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
Luz Angela Moreno-Gómez, Radiología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
9. Radiología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
10. Radiología Pediátrica, Fundación Hospital Pediátrico la Misericordia, Bogotá, D. C., Colombia.
Natalia Olaya, Patología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
2. Patología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, D. C., Colombia.
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