UBE2D2 and head and neck squamous cell carcinoma: Univariate Cox regression analysis revealed a significant correlation between the OS of HNSCC patients and several TCRRGs, namely CSF2, INPP5D, MAP2K1, MAP2K7, MAPK3, MAPK9, ORAI1, PIK3R3, PSMA1, PSMA7, PSMD10, PSMD2, PSMD7, SKP1, UBB, UBE2D2, and ZAP70 (Table 1).