miR‐125a‐5p promotes gastric cancer growth and invasion by regulating the Hippo pathway

OBJECTIVE: This study was carried out to explore the potential involvement of miR‐125a‐5p in the oncogenic effects of EphA2, TAZ, and TEAD2 and the activity of the Hippo signaling pathway in gastric cancer progression. METHODS: In vitro transfection of miR‐125a‐5p mimics or inhibitors, qRT‐PCR, colony formation assays, and cell invasion assays were used to assess the effect of miR‐125a‐5p on the growth and invasion in gastric cancer (GC). Male nude mice bearing tumors derived from human GC cells were used for evaluating the effects of miR‐125a‐5p on tumor growth. Luciferase reporter assay, immunofluorescence, immunohistochemistry, qRT‐PCR, and immunoblotting were performed to explore the role of miR‐125a‐5p in the epithelial‐mesenchymal transition (EMT) and association among miR‐125a‐5p, EphA2, TAZ, and TEAD2 in GC cells. RESULTS: MiR‐125a‐5p enhanced GC cell viability and invasion in vitro, whereas inhibition of miR‐125a‐5p using a specific inhibitor and antagomir suppressed cancer cell invasion and tumor growth. Moreover, inhibition of miR‐125a‐5p reversed EMT in vitro. miR‐125a‐5p upregulated the expression of EphA2, TAZ, and TEAD2, promoted TAZ nuclear translocation, and induced changes in the activity of the Hippo pathway by enhancing the expression of TAZ target genes. Finally, miR‐125a‐5p was overexpressed in late‐stage GCs, and positive correlations were observed with its targets EphA2, TAZ, and TEAD2. CONCLUSION: miR‐125a‐5p can promote GC growth and invasion by upregulating the expression of EphA2, TAZ, and TEAD2.