HDAC1 and colorectal cancer: As shown in Table 3, the expression level of HDAC1 in stage III-IV was higher than that in stage I-II colorectal cancer (OR = 2.94, 95% CI = 1.50–5.77), gastric cancer (OR = 1.47, 95% CI = 1.00–2.18) and liver cancer (OR = 2.30, 95% CI = 1.38–3.85) but not pancreatic cancer (OR = 1.05, 95% CI = 0.60–1.85) and esophageal cancer (only one study).