HDAC1 mRNA expression obtained by mRNA sequencing. (a) Boxplot of HDAC1 relative expression in normal tissue samples and LUAD samples. (b) Relative expression histogram of HDAC1 in normal tissue samples and in different LUAD grades. (c) Boxplot of HDAC1 mRNA expression in Caucasians, African Americans, and Asian ethnic groups compared with normal samples. (d) Comparison of mRNA levels of HDAC1 normally expressed in individuals with mRNA levels expressed in male and female LUAD patients. (e) Comparison of LUAD expression between normal individuals and LUAD patients aged 21–40, 41–60, 61–80, and 81–100 years. (f) Comparison of LUAD expression between normal individuals and nonsmokers, smokers, smokers for less than 15 years, and smokers for more than 15 years. ∗, P < 0.05; ∗∗, P < 0.01; ∗∗∗, P < 0.001; n.s, no significant. All the data in the above figures were statistically significant.