The present study not only points out possible important role for CADM1 shedding in the development and progression of emphysema in human ex-smokers as was shown in current smokers (Mimae et al., 2014), but also suggests that remodeling of the alveolar septa that progresses during a smoke cessation period may help establish long-lasting imbalances between proteases and antiproteases, which are recognized as the central etiology of emphysema (Travis et al., 2002; Tomashefski, 2008). Here, CADM1 is linked to pulmonary emphysema.