However, the levels of VEGF (1.9 folds; cancer: 528.3 ± 67.9 pg/ml; COPD: 1009.2 ± 122.8 pg/ml) and IL-8 (~9 folds; cancer: 16.5 ± 1.3 pg/ml; COPD: 146.7 ± 50.9 pg/ml) were significantly lower (P < 0.005) in lung cancer patients than COPD patients. Here, CXCL8 is linked to chronic obstructive pulmonary disease.