MicroRNA-218 inhibits bladder cancer cell proliferation, migration, and invasion by targeting BMI-1
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MicroRNAs (miRNAs) are recognized as important molecules and have emerged as important gene regulators in tumorigenesis. Growing evidence suggested that miR-218 was a tumor suppressor in many human cancers. However, its underlying role in bladder cancer (BCa) remains unclear. The aim of this study was to explore the effect of miR-218 on the proliferation, migration, and invasion of BCa cells. We found that miR-218 was frequently downregulated in BCa tissues compared with normal adjacent tissues. In vitro and in vivo assays demonstrated that miR-218 overexpression in the BCa cells inhibited cell proliferation, migration, and invasion. Luciferase reporter assay showed that BMI-1 was a direct target of miR-218. In addition, we found that miR-218 regulated the expression of BMI-1 and its downstream target (PTEN) and participated in the phosphorylation of AKT. Our findings indicate that miR-218 functions as tumor suppressor in BCa, and the miR-218/BMI-1 axis may provide novel diagnostic and therapeutic strategies for the treatment of BCa.
KeywordsMicroRNA-218 Bladder cancer BMI-1 Proliferation Migration Invasion
This work was supported by the Program for Development of Innovative Research Team of the First Affiliated Hospital of Nanjing Medical University, the Provincial Initiative Program for Excellency Disciplines of Jiangsu Province, the National Natural Science Foundation of China (Grant Nos. 81272832 and 81201997), the Natural Science Foundation of Jiangsu Province (Grant No. BK2011848), the Six Major Talent Peak Project of Jiangsu Province (Grant No. 2011-WS-121), the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), and Jiangsu Provincial Special Program of Medical Science (BL2012027). The funders had no role in study design, data collection, and analysis; decision to publish; or preparation of the manuscript.
Conflicts of interest
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