RPL13A and chronic obstructive pulmonary disease: We verified the mRNA levels of the top 10 hub genes in the COPD group, and we found that expression of 8 hub genes (RPLP0, RPL5, RPL32, RPL13A, FAU, RPL32, RPS21 and RPS11) was significantly downregulated in COPD tissues compared to the normal tissue consisted with the prediction results (Figures 6A–J).