The knockdown of PTEN was accompanied with the significant phosphorylation of Akt (p-Akt/total-Akt) (Fig. 5B, bottom), and enhanced the secretion of various cytokines, such as IL-6, CXCL8, CXCL10, CCL2, and CCL5 (Fig. 5C) in the cytokine array assay, all of which are known to be associated with the proinflammatory response in the pathogenesis of COPD (6). Here, CXCL8 is linked to chronic obstructive pulmonary disease.