PER2 and head and neck squamous cell carcinoma: Among these four genes, PER2 was particularly interesting not only because the H3K27me3 peaks at its promoter region were significantly higher in the OE-KDM6AS829D group compared to the OE-KDM6AS829A group (Fig. 4F), but also for three additional reasons: (1) In HNSCC, we observed significant downregulation of PER2 expression, and patients with low PER2 levels exhibited poorer survival rates (Supplementary Fig. 4C, D); (2) Per2 knockout in mouse promoted tumorigenesis [39]; (3) PER2 loss increased glycolysis in cancer cells [43].