BACKGROUND: The inactivation of the Hippo pathway lead to TAZ (PDZ-binding 
motif)/YAP (yes-associated protein) overexpression, and is associated with worse 
prognostic outcomes in various cancers including hepatocellular carcinoma (HCC). 
Although there are several reports of microRNA (miR) targeting for YAP, miR 
targeting for TAZ remains unclear. The aim of this study is to identify the miR 
targeting TAZ expression in HCC.
METHODS: MicroRNA expression was analysed using the Human miFinder 384HC 
miScript miR PCR array, and was compared between low and high TAZ expression 
cell lines. Then, we extracted miR-9-3p as a tumour-suppressor miR targeting 
TAZ. We examined the functional role of miR-9-3p using miR-9-3p mimic and 
inhibitor in HCC cell lines).
RESULTS: In HCC cell lines and HCC clinical samples, there was the inverse 
correlation between miR-9-3p and TAZ expressions. TAZ expression was induced by 
treatment of miR-9-3p inhibitor and was downregulated by treatment of miR-9-3p 
mimic. Treatment of miR-9-3p mimic inhibited cell proliferative ability with 
downregulated phosphorylations of Erk1/2, AKT, and β-catenin in HLF. Inversely, 
treatment of miR-9-3p inhibitor accelerated cell growth compared with control in 
HuH1.
CONCLUSIONS: MicroRNA-9-3p was identified as the tumour-suppressor miR 
targetting TAZ expression in HCC cells.