The Functional Study of MITF in Uveal Melanoma Cells

In this study, qRT-PCR and Western blot were used to find that the RNA level and protein level of MITF in human uveal melanoma cells were significantly higher than those in uveal melanocytes. The expression of MITF in uveal melanoma cells was down-regulated by RNA interference technique. MTS assay and cell plate cloning experiments showed that the proliferative ability of uveal melanoma cells were significantly inhibited after MITF down-regulation. Flow cytometry, hoechst staining and Caspase 3/7 activity test showed that the cell cycle was blocked and the level of apoptosis increased. Quantitative detection by RTCA xCELLigence DP detection system found that si-MITF could inhibit the migration and invasion of uveal melanoma cells. The expression levels of cell cycle-associated proteins p-Rb (retinoblastoma), CDK2 (cyclin-dependent kinase 2), CDK6, Cyclin D2 and Cyclin E2 in uveal melanoma cells were down-regulated by Western blot. The phosphorylation levels of FAK (focal adhesion kinase) and ERK (extracellular signal-regulated protein kinases) proteins, which are closely related to proliferation and migration decreased. This study shows that si-MITF can lead to G1 phase arrest of uveal melanoma cells, inhibiting cell proliferation, migration and invasion, and also promote cell apoptosis.