MicroRNA-199a-3p Inhibits Proliferation of Uveal Melanoma Cells

Objective: To investigate the effect of MicroRNA-199a-3p (miR-199a-3p) on proliferation of uveal melanoma cells. Methods: In this experimental research, real-time RT-PCR was performed to determine the level of miR-199a-3p in a human melanocyte cell line (UM96) and uveal melanoma cell line (OCM290). Lipofectamine was used to transfect miR-199a-3p into uveal melanoma cells to upregulate the expression level of miR-199a-3p. A scrambled oligonucleotide was transfected into uveal melanoma cells as the negative control (NC). The proliferation of uveal melanoma cells was examined by cell proliferation assay (MTS) and clone formation experiments. Flow cytometry was performed to detect the cell cycle of uveal melanoma cells. In addition, Western blot was used to identify the protein level of cell cycle-related proteins. Data analysis was performed by independent t-tests. Results: The level of miR-199a-3p in uveal melanoma cells significantly decreased compared tomelanocyte cells (t=13.2, P<0.001). After the transfection, the MTS assay showed that the relative number of cells transfected with miR-199a-3p (23.8%±1.7%) was significantly lower than those transfected with NC (t=78.1, P<0.001). The recovery expression level of miR-199a-3p inhibited colony formation, and also induced G1-phase arrest in uveal melanoma cells (t=-8.5, P=0.001). Furthermore, it was found that miR-199a-3p could deregulate the protein level of cyclin-dependent protein kinases (CDK2, CDK4) and the transcription factor (E2F1) (t=10.3, P=0.001; t=9.9, P=0.001; t=10.4, P<0.001). Conclusion: miR-199a-3p inhibits the proliferation of uveal melanoma cells by preventing the cell cycle process. Key words: MicroRNA-199a-3p; uveal melanoma; proliferation