PPL and head and neck squamous cell carcinoma: Furthermore, according to MCC scores from the CytoHubba plugin in Cytoscape, the top 10 HNSCC-related genes were screened out (namely S100A8, S100A9, IL1RN, CSTA, ANXA1, KRT4, TGM3, SCEL, PPL, and PSCA) and all their expression patterns were found be downregulated in HNSCC tissues compared with the normal controls.