ARTÍCULO

Study of circulating microRNA-125b levels in serum exosomes in advanced melanoma

Autores: Alegre Martínez, Estíbaliz; Fernández de Sanmamed Gutiérrez, Miguel; Rodríguez Jiménez, María del Carmen Milagros; Carranza Rua, Omar Esteban; Martín Algarra, Salvador; González Hernández, Álvaro
Título de la revista: ARCHIVES OF PATHOLOGY AND LABORATORY MEDICINE
ISSN: 0003-9985
Volumen: 138
Número: 6
Páginas: 828 - 832
Fecha de publicación: 2014
Resumen:
CONTEXT: Malignant melanoma is an aggressive tumor that produces exosomes, which contain microRNAs (miRNAs) that could be of utility in following tumoral cell dysregulation. MicroR-125b is a miRNA whose down-regulation seems to be implicated in melanoma progression. OBJECTIVE: To analyze miR-125b levels in serum, and in exosomes obtained from serum, from patients with advanced melanoma. DESIGN: Serum samples were obtained from 21 patients with advanced melanoma, from 16 disease-free patients with melanoma, and from 19 healthy volunteers. Exosomes were isolated from serum by precipitation, and miR-16 and miR-125b levels were quantified by real-time polymerase chain reaction. RESULTS: MicroR-16, but not miR-125b, was detected in all samples, and miR-16 levels were significantly higher in serum than they were in exosomes. MicroR-16 expression levels did not differ significantly between the 2 groups (patients with melanoma and healthy donors). There was a significant relationship between miR-125b and miR-16 levels in exosomes. Additionally, miR-125b levels in exosomes were significantly lower in patients with melanoma compared with disease-free patients with melanoma and healthy controls. CONCLUSIONS: Exosomes can provide a suitable material to measure circulating miRNA in melanoma, and miR-16 can be used as an endogenous normalizer. Lower levels of miR-125b in exosomes obtained from serum are associated with advanced melanoma disease, probably reflecting the tumoral cell dysregulation.