It was recently shown that the consequences of MMP-2 and MMP-9 (gelatinase A and gelatinase B, respectively) levels rising can be referred to as acute and chronic asthma, idiopathic pulmonary fibrosis [40], disruption of the blood-brain barrier [35], hepatic fibrosis (mainly due to MMP-2 overexpression) [41], and that these MMPs are the key molecules for tumor invasion [42] and congestive heart failure [43]. This evidence concerns the gene MMP9 and idiopathic pulmonary fibrosis.