CCN1 and chronic obstructive pulmonary disease: Although, there was no obvious correlation of serum TNF-α with CYR61 in control cases (Figure 4L), serum CYR61 was positively associated with TNF-α in all cases (Figure 4J, r = 0.177, P = 0.001) and COPD patients (Figure 4K, r = 0.329, P < 0.001).