Receiver operator characteristic curve (AUC) analysis additionally showed that the mutually exclusive expression of KLF17 with uPA could predict lymph node metastasis in lung adenocarcinoma, the sensitivity and specificity for diagnose to lymph node metastasis was 81.2% and 71.4% respectively, and the AUC = 0.758 (P = 0.005), making it a better predictive factor than uPA overexpression alone (sensitivity = 81.2%, specificity = 59.3%, AUC = 0.703, P = 0.028) or low KLF17 expression alone (sensitivity=37.5%, specificity = 59.6%, AUC = 0.484, P = 0.86) (Figure 4D). The gene discussed is KLF17; the disease is lung adenocarcinoma.