PDCL2 and head and neck squamous cell carcinoma: We also found that FCRL1, LRATD1, and PLA2G3 were prognostic protective factors for the OS of the HNSCC patients, whereas the AC117422.1, AC117422.1, AC128687.2, AL161431.1, PDCL2, and SPRR3 were prognostic risk factors according to the univariate Cox regression analysis and K-M analysis (Figures 4(j)–4(r)).