MicroRNAs (miRNAs) have been shown to play a pivotal role in the pathogenesis and maintenance of liver fibrosis by altering expression of their downstream target genes. However, their role in radiation-induced liver fibrosis has not been assessed in detail. Here, we investigated the role of miR-146a-5p and the target gene in regulation of fibrosis-related markers in the human hepatic stellate cell line LX2. LX2 cells were stimulated with 8 Gy of X rays and various concentrations of TGF-