Circ_0002770, acting as a competitive endogenous RNA, promotes proliferation and invasion by targeting miR-331-3p in melanoma.

Melanoma is a kind of tumor that originates from melanocytes and is characterized by chemoresistance and distant metastasis. Although the complete pathogenesis of melanoma remains unclear, increasing evidence suggests that circular RNAs (circRNAs) may be involved. In the present study, we identified a circular RNA, circ_0002770, which is produced from the well-known oncogene MDM2, and was sharply increased in melanoma and correlated with a poor prognosis. Knockdown of circ_0002770 suppressed melanoma cell invasion, migration and proliferation. Mechanistically, circ_0002770 acted as a sponge of miR-331-3p and could indirectly regulate DUSP5 and TGFBR1. Inhibition of miR-331-3p reversed the inhibitory effect of si-circ_0002770 on melanoma cell proliferation and invasion. In vivo evidence further confirmed that silencing circ_0002770 inhibited melanoma tumor formation. In conclusion, circ_0002770 facilitated melanoma cell proliferation, invasion and migration by sponging miR-331-3p and modulating DUSP5 and TGFBR1.