MiR-543 promotes cell proliferation and metastasis of renal cell carcinoma by targeting Dickkopf 1 through the Wnt/β-catenin signaling pathway

Background: Renal cell carcinoma (RCC) is a common malignancy with high morbidity. MicroRNAs (miRNAs) have been demonstrated to be critical post-transcriptional regulators in tumorigenesis. This study aimed to investigate the effect of miR-543 on the proliferation and metastasis of RCC. Material and Methods: The expression of miR-543 was examined in clinical samples and RCC cell lines. A498 and 786-O cell lines were employed and transfected with miR-543 inhibitor or miR-543 mimics. The correlation between miR-543 and DKK-1 was determined by luciferase reporter assay. Cell viability and cell cycle were determined by CCK8 and flow cytometry assay. Cell migration and invasion capacity were examined by transwell assay. The protein level of DKK1, β-catenin and pGSK-3β were analyzed by western blotting. Results: miR-543 was found to be up-regulated in RCC cell lines. Further studies identified DKK-1 as a direct target of miR-543. Moreover, miR-543 overexpression suppressed the expression of DKK-1, and promoted cell proliferation, migration and invasion capacity, while knockdown of miR-543 abrogated above results. MiR-543 knockdown also decreased β-catenin and pGSK-3β levels. In vivo assay verified that miR-543 acts as an oncogene through the regulation of DKK-1 and Wnt/β-catenin signaling pathway. Conclusion: Our study indicated that miR-543 negatively regulate the expression of DKK-1 in vitro. MiR-543 promotes malignancy phenotypes of RCC both in vitro and in vivo. This regulatory effect of miR-543 may be associated with Wnt/β-catenin signaling pathway. Therefore, miR-543 could be used as a biomarker for predicting the progression of RCC.