Subsequently, to investigate the effect of NIFK on the proliferation of HNSCC, we conducted the plate cloning assay with Cal27/SCC25 control, sh-NIFK#1, and sh-NIFK#2 cells, and the results revealed that colony formation in Cal27 and SCC25 cells was inhibited by NIFK shRNA (Figures 8E–H). This evidence concerns the gene NIFK and head and neck squamous cell carcinoma.