CircFAT1 Promotes the Proliferation and Invasion of Malignant Melanoma through miR375-SLC7A11 Signal Axis.

Background: Circular RNA, as a member of noncoding RNA, plays an important role in the occurrence, development and metastasis of tumor cells. So far, the correlation between circular RNA and malignant melanoma remains obscure.

Methods: RNA expression of circFAT1 and miR-375 in malignant melanoma (MM) tissues and cell lines was detected by RT-PCR. The proliferation, cloning, migration and invasion of SK-Mel-28 and A375 cells were assessed using CCK-8 test, clone formation and Transwell assay, respectively. CircRNA immunoprecipitation was used to validate the relationship between circFAT1 and miR-375. The binding between circFAT1 and miR-375, as well as SLC7A11 and miR-375 were verified by luciferase assay.

Results: In our study，the circFAT1 was significantly overexpressed in the MM tissue than melanocytic nevi. , the expression of miR-375 in MM tissue was lower than in melanocytic nevi tissue. The underexpression of circFAT1 with siRNA plasmids significantly suppressed the proliferation, invasion and clone formation of MM cell line. Mechanistically, circFAT1 positively regulates the expression level of SLC7A11 by sponging miR-375. The promotive effects of circFAT1 on the proliferation and invasion ability of MM cells were reversed by the upregulation of miR-375.

Conclusion: circFAT1 promotes the proliferation, invasion and clone formation of malignant melanoma cells by improving the expression level of SLC7A11 sponging miR-375.