miR-320c Regulates SERPINA1 Expression and Is Induced in Patients With Pulmonary Disease

[Display omitted] Alpha-1 antitrypsin deficiency (AATD) is a genetic condition resulting in lung and liver disease with a great clinical variability. MicroRNAs have been identified as disease modifiers; therefore miRNA deregulation could play an important role in disease heterogeneity. Members of miR-320 family are involved in regulating of multiple processes including inflammation, and have potential specific binding sites in the 3′UTR region of SERPINA1 gene. In this study we explore the involvement of miR-320c, a member of this family, in this disease. Firstly in vitro studies were carried out to demonstrate regulation of SERPINA1 gene by miR-320. Furthermore, the expression of miR-320c was analyzed in the blood of 98 individuals with different AAT serum levels by using quantitative PCR and expression was correlated to clinical parameters of the patients. Finally, HL60 cells were used to analyze induction of miR-320c in inflammatory conditions. Overexpression of miR-320 members in human HepG2 cells led to inhibition of SERPINA1 expression. Analysis of miR-320c expression in patient's samples revealed significantly increased expression of miR-320c in individuals with pulmonary disease. Additionally, HL60 cells treated with the pro-inflammatory factor lipopolysaccharide (LPS) showed increase in miR-320c expression, suggesting that miR-320c responds to inflammation. Our findings demonstrate that miR-320c inhibits SERPINA1 expression in a hepatic cell line and its levels in blood are associated with lung disease in a cohort of patients with different AAT serum levels. These results suggest that miR-320c can play a role in AAT regulation and could be a biomarker of inflammatory processes in pulmonary diseases. La deficiencia de alfa-1 antitripsina (DAAT) es una condición genética que produce enfermedad pulmonar y hepática con una gran variabilidad clínica. Los microARN se han identificado como modificadores de la gravedad de algunas enfermedades y su desregulación podría desempeñar un papel en la heterogeneidad de esta enfermedad. Los miembros de la familia miR-320 regulan múltiples procesos, incluyendo la inflamación, y tienen lugares de unión en la región 3’UTR del gen SERPINA1. En este estudio exploramos la implicación del miR-320c, un miembro de esta familia, en la DAAT. Primero se realizaron estudios in vitro para demostrar la regulación del gen SERPINA1 por parte del miR-320. Además, se analizó la expresión de miR-320c en la sangre de 98 individuos con