Detección del gen fusión PML-RARα en pacientes colombianos con leucemia mieloide aguda / Detection of the PML-RARα fusion gene in Colombian patients with acute myeloid leukemia

Resumen Introducción: la leucemia promielocítica aguda es un subtipo de leucemia mieloide aguda caracterizada por la presencia de una translocación entre los cromosomas 15 y 17 que provoca la formación de un gen fusión denominado PML/RARα. Determinar la presencia de este gen fusión es crítico para estos pacientes ya que su presencia hace el diagnóstico de la enfermedad, aún sin tener resultados de patología. Con esta investigación se busca ajustar e implementar una prueba altamente sensible y específica para la detección del reordenamiento PML/RARα. Métodos: a partir de sangre periférica se extrajo RNA de pacientes diagnosticados con leucemia mieloide aguda en dos instituciones de Antioquia (Colombia). Se realizó RT-PCR anidada para la detección de PML/RARα, ajustando un protocolo previamente publicado. Resultados: se ajustó y estandarizó un método para detectar mediante RT-PCR el gen fusión PML/RARα. Mediante esta técnica se logró identificar la traslocación en cuatro pacientes (22 %) de la cohorte estudiada. Conclusiones: los resultados están de acuerdo con estudios previos. La detección de esta y otras alteraciones citogenéticas mediante pruebas moleculares permitirá tener información valiosa a nivel de diagnóstico y pronóstico de los pacientes con leucemia mieloide aguda en Antioquia.

Abstract Introduction: acute promyelocytic leukemia is a subtype of acute myeloid leukemia characterized by the presence of a translocation between chromosomes 15 and 17, which causes the formation of a fusion gene called PML/RARα. Determining the presence of this fusion gene is critical for these patients, since their presence makes the diagnosis of the disease, even with no pathology results This research seeks to adjust and implement a highly sensitive and specific test for the diagnosis of this cytogenetic abnormality. Methods: peripheral blood samples from patients diagnosed with acute myelocytic leukemia were collected in two institutions of Antioquia (Colombia), from which RNA was extracted and nested RT-PCR was performed, adjusting a previously published protocol. Results: we adjusted and standardized a method to detect the PML/RARα fusion gene by RT-PCR. Using this technique, translocation was identified in four patients (22%) of the studied cohort. Conclusions: our results agree with previous studies. The detection of this and other cytogenetic alterations by means of molecular tests will allow to have valuable information at the level of diagnosis and prognosis of patients with AML in Antioquia.

Role of promyelocytic leukemia protein expression in the pathogenesis of psoriasis / 西安交通大学学报(医学版)

Objective To study the relationship between promyelocytic leukemia(PML) protein and apoptosis and their roles in the pathogenesis of psoriasis. Methods Immunohistochemical techniques were employed to study the expression of PML protein in the uninvolved skin, progressive plaque lesions and regressive lesions. Apoptosis was detected with terminal deoxynucleotidyl transferase-mediated dUTP-DIG nick end labeling(TUNEL). Results There was a significantly upregulated expression of PML protein in progressive plaque lesions, compared with that in uninvolved skin adjacent to the lesions and regressive lesions, and there was nearly no expression in normal skin; there was obvious apoptosis of keratinocytes in the epidermis with intensive PML protein staining. Conclusion The increased apoptosis of keratinocytes in the lesions of psoriasis induced by PML protein might be a homeostatic mechanism to the hyperplasia of keratinocytes.