On the contrary, SNORD33 and SNORD76 showed significantly higher expressions in plasma of the NSCLC group as compared with COPD group (All P < 0.01), whereas there was no statistical difference regarding expressions of the two genes between COPD and healthy groups (All P > 0.05; Table 3, Fig. 2). Here, SNORD33 is linked to chronic obstructive pulmonary disease.