miRNA-543 promotes cell migration and invasion by targeting SPOP in gastric cancer

Junfei Xu,1,2 Feiran Wang,2 Xi Wang,3 Zhixian He,2 Xinguo Zhu1 1Department of General Surgery, First Affiliated Hospital, Soochow University, Suzhou, People’s Republic of China; 2Department of General Surgery, Affiliated Hospital, Nantong University, Nantong, People’s Republic of China; 3Medical College of Nantong University, Nantong, People’s Republic of China Background/purpose: Given the emerging role of microRNA (miRNA) in cancer progression, we investigated the role and mechanism of miRNA-543 (miR-543) in gastric cancer (GC).Materials and methods: Real-time quantitative polymerase chain reaction was conducted to quantify the expression of miR-543. Luciferase reporter assay was used to confirm the association between speckle-type POZ protein (SPOP) and 3'-UTR. Moreover, the role of miR-543 and SPOP in GC was detected using transwell assays. In addition, we investigated the function of miR-543 in the epithelial–mesenchymal transition (EMT) progression.Results: miR-543 was upregulated in GC. We identified SPOP as a direct target of miR-543, revealing its expression to be inversely correlated with miR-543 expression in GC tissues. Moreover, restoration of SPOP could inhibit miR-543-induced GC cell migration and invasion, whereas downregulation of miR-543 inhibited cell migration and invasion, which was partly abrogated by SPOP knockdown. Furthermore, our data also showed that miR-543 induced EMT of GC cells.Conclusion: Our results demonstrated that miR-543 functions as a crucial oncogenic miRNA in GC. It exerts strong tumor-promoting effects through targeting SPOP in GC cell migration and invasion. Keywords: gastric cancer, miR-543, SPOP, EMT, invasion and migratio