Objective:To investigate the expression and role of DEAD-box RNA helicases 5(DDX5 helicases)in head and neck squamous carcinoma(HNSCC).Methods:Tissue microarray microarray was used to assess relevant mRNA expression profile data,and R software was used to screen differential mRNAs(DEGs).The expression level of DDX5 was predicted using GEPIA 2,TCGA databases,and detected by immunohistochemistry,western blot and RT-qPCR in the HNSCC tissue and cell lines.Based on high-throughput sequencing data of DECs,differentially expressed miRNAs(DEMIs)relevant DDX5 competitive endogenous RNA network(ceRNA)was constructed.The software cytoscape was used to visualize the ceRNA network map and further screen the regulatory ax-is.Results:The results of microarray screening revealed that DDX5 expression in HNSCC was upregulated.Immunohistochemistry ver-ified that DDX5 was stronger expressed in the nuclei of squamous carcinoma cells.qPCR results suggested that significant expression of DDX5 mRNA at the tissue and cellular levels(P＜0.05).Western blot results showed high expression of DDX5 protein in the tissues.The ceRNA network was constructed,from which the relevant HNSCC axis circRNA-039626-miR-222-5p-DDX5 was identified.Con-clusion:DDX5 is highly expressed in HNSCC,and the circRNA-039626-miR-222-5p-DDX5 axis may be a potential regulatory axis for the development of HNSCC.