Expression of miR-181 is associated with β-catenin level. (A) Western blot analysis of β-catenin and β-actin in Hep3B, HuH7, HuH1, MHCC97 and Smmc7721 HCC cell lines. The relative intensity of β-catenin was listed on the top of individual western blot band. (B) qRT-PCR analysis of the four mature miR-181s in five HCC cell lines. Levels of miR-181s in these HCC cell lines were measured in triplicate and normalized by U6 level. After further normalization by the reading in adult primary human hepatocytes, the relative level for each miRNA was shown as the mean ± standard deviation. (C) qRT-PCR analysis of the four mature miR-181s in liver tissues from three wild-type mice and two Klotho knockout mice. miR-181s' level in these tissues was measured in triplicate, normalized to levels of U6.