Alegre, EstíbalizSanmamed, Miguel F.Rodríguez-Jiménez, CarmenCarranza, OmarMartín-Algarra, SalvadorGonzález, Álvaro2024-12-032024-12-032014Alegre, E., Sanmamed, M. F., Rodríguez-Jiménez, C. et al. (2024). Study of Circulating MicroRNA-125b Levels in Serum Exosomes in Advanced Melanoma. Archives of Pathology & Laboratory Medicine, Vol. 138 (6), pp. 828–832.0003-9985https://hdl.handle.net/10641/5507Context.—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 downregulation 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.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/journal articleopen access10.5858/arpa.2013-0134-OA