By using the TCGA HNSCC database, we performed Kaplan–Meier analysis with respect to CHRNA5 mRNA levels, HNSCC subdivision into OSCC or non-OSCC, and the signature obtained from the combination of CHRNA5 mRNA levels with HNSCC subdivision to determine the overall survival (Figure 2A) or recurrence-free survival (RFS) (Figure 2B) probability. The gene discussed is CHRNA5; the disease is head and neck squamous cell carcinoma.