MMP1 and pulmonary fibrosis: In addition to aging, MMP1 is a biomarker for several cancers, pulmonary fibrosis and potentially Alzheimer’s disease (Bhat et al., 2012; Chen et al., 2016b; Rosas et al., 2008), whereas STC1 is a diagnostic and prognostic biomarker for cancers, pulmonary fibrosis, renal ischemia/reperfusion injury and Alzheimer’s disease (Chang et al., 2015; Ohkouchi et al., 2015; Pan et al., 2015; Shahim et al., 2017).