Circ-0079593 promotes proliferation and migration of melanoma cells by sponging microRNA-433 and elevating EGFR expression.

OBJECTIVE The aim of this study was to analyze the biological effects of circ-0079593 and its potential mechanism in the progression of melanoma. PATIENTS AND METHODS Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was carried out to detect circ-0079593 expression in melanoma tissue samples and cell lines, and the relationship between circ-0079593 expression and prognosis of patients with melanoma was analyzed based on collected clinical information. Then, the melanoma cell line stably overexpressing circ-0079593 was constructed using lentiviral stable transfection technique, and then, Cell Counting Kit-8 (CCK-8) and transwell assays were carried out to detect the proliferation rate, migration, as well as invasion abilities of melanoma cells, respectively. In addition, the potential binding targets of circ-0079593 were searched through bioinformatics analysis, and the results were verified by Dual-Luciferase assay. RESULTS It was found that, in comparison with the normal control group, circ-0079593 showed a significantly high expression in melanoma tissues and cell lines, which predicted a poor prognosis of melanoma patients. In vitro experiments showed that the overexpression of circ-0079593 remarkably enhanced proliferation rate, as well as invasion ability of melanoma cells. Moreover, bioinformatics data analysis revealed that there exist binding sites of microRNA-433 both in circ-0079593 and EGFR. Meanwhile, the results of the Luciferase assay confirmed that circ-0079593 probably bound to microRNA-433, as an endogenous competitive RNA (ceRNA), to regulate EGFR expression. At last, cell reverse experiments demonstrated that the overexpression of microRNA-433 could attenuate the capacity of melanoma cells to proliferate and migrate, while simultaneous overexpression of circ-0079593 partially restored those cell functions. CONCLUSIONS In melanoma, circ-0079593 may serve as a cancer-promoting gene to accelerate the rates of cell proliferation and migration, which may exert its effects by elevating EGFR expression by binding to microRNA-433.