NCOA4 inhibits glioma progression by suppressing the Sonic Hedgehog pathway and its overexpression indicates a better glioma prognosis.

BACKGROUND: Nuclear receptor coactivator 4 (NCOA4) is known to be involved in ferroptosis. However, its expression and function in gliomas are still unclear. OBJECTIVE: To assess the expression of NCOA4 in gliomas and explore the mechanisms by which NCOA4 affects glioma progression. METHODS: RNA-seq data for glioma patient tissues and normal brain tissues were obtained from The Cancer Genome Atlas and the Genotype Tissue Expression project. NCOA4 expression was assessed by Western blotting (WB) and immunohistochemistry (IHC). Overexpression and knockdown of NCOA4 were induced in glioma cell lines via transduction of recombinant adenovirus encoding NCOA4 and NCOA4 siRNA, respectively. Cell Counting Kit-8 (CCK-8), Transwell and flow cytometry assays were performed to assess cell proliferation, invasion and apoptosis. RESULTS: WB and IHC revealed that NCOA4 was markedly downregulated in glioma cell lines and human specimens compared to controls, and high NCOA4 expression was associated with a better glioma prognosis. NCOA4 overexpression inhibited glioma cell growth and invasion and induced apoptosis, whereas NCOA4 knockdown promoted glioma cell growth. PTCH1 was predicted to interact with NCOA4 via bioinformatics analysis. NCOA4 overexpression increased the expression of PTCH1 and suppressed the expression of SMO, Bcl-2 and the nuclear translocation of Gli1, indicating that NCOA4 suppresses the SHH pathway. PTCH1 knockdown reversed the inhibitory effects of NCOA4 on the malignant behaviours of glioma cells. CONCLUSIONS: These results suggest that NCOA4 is downregulated in gliomas and that its overexpression predicts better overall survival in glioma patients. Mechanistically, NCOA4 overexpression inhibits the progression of glioma by suppressing the SHH pathway.