Patients with stage I lung adenocarcinoma with both high EZH2 and high HDAC1 mRNA expression had worse OS as compared to patients with either or both markers low in both datasets (MDACC dataset: hazard ratio (HR = 2.97; P = 0.031 and TCGA dataset: HR = 2.6; P = 0.041) and multivariate analysis (MDACC: HR = 2.92; P = 0.034 and TCGA: HR = 3.17; P = 0.016; Figure 2). Here, HDAC1 is linked to lung adenocarcinoma.