CASP9 and idiopathic pulmonary fibrosis: Consistent with the mitochondrial dysfunction in IPF, in the present study, we found that corisin and the culture supernatant of bacteria expressing corisin-harboring transglycosylases predominantly induce activation of caspase-9, and that corisin stimulation significantly affects the expression of factors that regulate the mitochondrial outer membrane permeabilization (Bcl2, Bcl-XL, Bax, cyclin D1) and inhibitors of apoptosis proteins (BIRC1, BIRC5, BIRC7), and p53 activation.