For example, a 7-mRNA signature (AATF, APP, GNPDA1, HPRT1, LASP1, P4HA1 and ILF3) of head and neck squamous cell carcinoma (HNSCC) shows a moderate predictive ability for 5-year OS (AUC for training set, 0.75; testing set, 0.66) (Shen et al., 2017a). The gene discussed is APP; the disease is head and neck squamous cell carcinoma.