MicroRNA­543 inhibits proliferation, invasion and induces apoptosis of glioblastoma cells by directly targeting ADAM9.

Glioma is the most common type of malignant brain tumor in humans and accounts for 81% of all malignant brain tumor cases in adults. The abnormal expression of microRNAs (miRs) has been reported to be important in the formation and progression of various types of human cancer, including glioblastoma (GBM). Therefore, studies into the expression, and roles of microRNAs as diagnostic and prognostic markers, as well as their therapeutic value for patients with GBM are warranted. The expression and roles of miR­543 have been reported in several types of human cancer. However, the role of miR­543 in GBM remains unclear. In the current study, the expression pattern of miR­543 in GBM, the effects of miR­543 on GBM cells and the underlying molecular mechanism was determined. The results of the present study demonstrated that miR­543 was significantly downregulated in GBM tissue samples and cell lines. Furthermore, the upregulation of miR­543 inhibited GBM cell proliferation and invasion, as well as promoted cell apoptosis. In addition, a disintegrin and metalloproteinase 9 (ADAM9) was identified to be a direct target gene of miR­543. Furthermore, ADAM9 was significantly upregulated in GBM tissue samples and its expression was inversely correlated with miR­543 expression in GBM tissue, suggesting that miR­543 downregulation may contribute to ADAM9 upregulation in GBM. Finally, the results of the rescue experiment indicated that ADAM9 overexpression significantly reversed the effects of miR­543 on the proliferation, invasion and apoptosis of GBM cells, suggesting that miR­543 serves as a tumor suppressor in GBM through ADAM9 regulation. Overall, these findings indicate that the miR­543/ADAM9 signaling pathway may provide as a potential therapeutic strategy for GBM.