The results showed that patients with lung adenocarcinoma with low expression levels of BUB1B (Log rank P = 3.8e −05, P (HR) = 5.1e −05 ), CDC45 (log rank P = 0.0032, p (HR) = 0.0035), BUB1 (log rank P = 0.0024, p (HR) = 0.0026 ), TTK [log rank P = 0.00029, P (HR) = 0.00034], BRCA1 [log rank P = 0.0035, P (HR) = 0.0038], TOP2A [log rank P = 0.011, P (HR) = 0.012], NDC80 [log rank P = 0.0027, P (HR) = 0.003], MCM2 [log rank P = 0.02, P (HR) = 0.021], and DTL [log rank P = 0.0016, P (HR) = 0.0018] had significantly higher overall survival than those with high gene expression levels (P < 0.05). The gene discussed is MCM2; the disease is lung adenocarcinoma.