In addition to regulating apoptosis and immune response, MMP8 also plays a protective role in lung inflammation (Gueders et al., 2005), cancer progression (Balbin et al., 2003; Gutierrez-Fernandez et al., 2008; Korpi et al., 2008), and wound healing (Gutierrez-Fernandez et al., 2007). Here, MMP8 is linked to inflammation.