Figure 2
High TRAP expression is associated with COPD. (a) TRAP mRNA expression was significantly higher in lung tissue of patients with COPD (n = 311) than in their respective controls (n = 270). (b) TRAP mRNA expression was significantly higher in lung tissue of current smoking control individuals (n = 73) than in control exsmokers after at least 5 years of smoking cessation (n = 106). (c) TRAP mRNA expression correlated negatively with lung function (FEV1). (d) TRAP mRNA expression was only significantly higher in lung tissue of patients with severe COPD (GOLD stage IV) compared to control individuals, and not in patients with less severe COPD compared to the controls. Differences between 2 groups were tested with a Mann-Whitney U test, between multiple groups with a Kruskal-Wallis test with a Dunn’s correction for multiple testing. The correlation between TRAP mRNA expression and FEV1 was calculated using a Spearman correlation test. A p value smaller than 0.05 was considered significant.
