The objective of this study is to investigate the effects of CCN2 gene silencing and CCN2 deletion on the development of a disease phenotype using fibroblast cultures and two experimentally-induced models of lung disease: bleomycin-induced pulmonary fibrosis and the chronic hypoxia/Sugen model of pulmonary arterial hypertension (PAH). This evidence concerns the gene CCN2 and pulmonary fibrosis.