Regulation of Coagulation Factor XI expression by MicroRNAs in the Human Liver

High levels of factor XI (FXI) increase the risk of thromboembolic disease. However, the genetic and environmental factors regulating FXI expression are still largely unknown. The aim of our study was to evaluate the regulation of FXI by microRNAs (miRNAs) in the human liver. In silico prediction yielded four miRNA candidates that might regulate FXI expression. HepG2 cells were transfected with miR-181a-5p, miR- 23a-3p, miR-16-5p and miR-195-5p. We used mir-494, which was not predicted to bind to F11, as a negative control. Only miR-181a-5p caused a significant decrease both in FXI protein and F11 mRNA levels. In addition, transfection with a miR-181a-5p inhibitor in PLC/PRF/5 hepatic cells increased both the levels of F11 mRNA and extracellular FXI. Luciferase assays in human colon cancer cells deficient for Dicer (HCT-DK) demonstrated a direct interaction between miR-181a-5p and 3'untranslated region of F11. Additionally, F11 mRNA levels were inversely and significantly correlated with miR-181a-5p levels in 114 healthy livers, but not with miR-494. This study demonstrates that FXI expression is directly regulated by a specific miRNA, miR-181a-5p, in the human liver. Future studies are necessary to further investigate the potential consequences of miRNA dysregulation in pathologies involving FXI. In the study presented here, we report arrays including 1,898 human mature miRNAs (LCSciences, Houston, TX; Sanger mirBase Release 18.0) using total RNA extracted from a healthy human liver sample E122; a Caucasian donor that gave informed consent were provided by biobanc CIBERehd. Human liver studies were apporved by Local Ethics Committee from Hospital Universitario Morales Meseguer in Murcia. In the study presented here, we report arrays including 2,019 human mature miRNAs (LCSciences, Houston, TX; Sanger mirBase Release 19.0) using total RNA extracted from 3 healthy human liver samples (662, 664, 771) from Caucasian donors that gave informed consent were provided by St. Jude Liver Resource at St. Distribution System and by cooperative Human Tissue Network. Human liver studies were apporved by Local Ethics Committee from Hospital Universitario Morales Meseguer in Murcia