MATERIAL and METHODS: The expression of miR-3918, FOXD3-AS1, and CCND1 was measured in glioblastoma cells and tissues using reverse transcriptase quantitative PCR (RT-qPCR). The effect of FOXD3-AS1 silencing on the proliferation of glioblastoma cells was assessed in vitro using CCK-8 and colony formation assays and in vivo using xenograft mouse models. Additionally, the expression levels of the apoptosis-related proteins, Bcl-2 and Bax, were assessed using western blotting. Bioinformatic analysis and luciferase reporter assays assisted by RNA immunoprecipitation (RIP) and RNA pull-down experiments were conducted to validate the interactions among FOXD3-AS1, CCND1, and miR-3918.

RESULTS: FOXD3-AS1 and CCND1 were highly expressed in glioblastoma tissues and cells, whereas miR-3918 was poorly expressed. The expressions of FOXD3-AS1 and CCND1 were inversely associated with miR-3918 levels in glioblastoma tissues. FOXD3-AS1 silencing weakened the proliferative capacity and accelerated apoptosis of glioblastoma cells in vitro and hampered tumor growth in vivo. Mechanical investigations showed that FOXD3-AS1 knockdown increased miR-3918 expression and inhibited glioblastoma cell growth. Meanwhile, the miR-3918 inhibitor restored CCND1 expression and induced the opposite outcome.

CONCLUSION: FOXD3-AS1 facilitates the CCND1-driven progression of glioblastoma by serving as a competing endogenous RNA (ceRNA) for miR-3918. This suggests that FOXD3-AS1 may be a potential therapeutic target for the management of glioblastoma development. Keywords : Glioblastoma, Competing endogenous RNA (ceRNA), lncRNA FOXD3-AS1, Proliferation