The Circular RNA circSKA3 Facilitates the Malignant Biological Behaviors of Medulloblastoma via miR-520 h/CDK6 Pathway

Abstract

Circular RNAs (circRNAs) are reported to participate in the development of diverse human malignancies. This work investigated the mechanism of circSKA3 in modulating medulloblastoma progression. A total of 15 cases of medulloblastoma were collected in this work. Daoy cells were used to construct cell models. The expression level of circSKA3, microRNA-520 h (miR-520 h), and cyclin-dependent kinase 6 (CDK6) mRNA in tissues or cells was examined by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was employed to detect CDK6 protein expression. CCK-8 experiment, Transwell assay, and flow cytometry were applied to detect the regulatory effects of circSKA3 on cell proliferation, migration, invasion, and cell cycle. Dual-luciferase reporter gene experiment was executed to determine the relationship between circSKA3 and miR-520 h, and between miR-520 h and CDK6. circSKA3 was remarkably up-modulated in medulloblastoma tissues. CircSKA3 depletion markedly suppressed Daoy cell viability, migration, invasion, and cell cycle progression. CircSKA3 overexpression induced the opposite effects. circSKA3 could decoyed miR-520 h, which targeted the 3' UTR of CDK6. circSKA3 expression in medulloblastoma tissues was negatively correlated with miR-520 h expression and positively correlated with CDK6 expression. "Rescue" experiments revealed that miR-520 h down-modulation or CDK6 overexpression remarkably counteracted the inhibitory effect of circSKA3 knockdown on Daoy cells. circSKA3 facilitates medulloblastoma progression through miR-520 h/CDK6.

Keywords: CDK6; Medulloblastoma; circSKA3; miR-520 h.