This approach confirmed that known tumor suppressor genes and oncogenes (e.g., PIK3CA, EGFR, CDKN2A, NOTCH1, TP53, FBXW7) play a role in HNSCC, and pathway analyses found that—amongst others—proliferation, differentiation, and PI3K pathways were frequently affected [30–32]. This evidence concerns the gene PIK3CA and head and neck squamous cell carcinoma.