These histopathological findings of BLM-induced pulmonary fibrosis in the MKK6-constitutive active (MKK6-CA) group were more severe and extensive than those in the wild-type (WT) group, whereas those in the p38-dominant negative (p38-DN) group were less severe and extensive than those in the WT group. Here, MAP2K6 is linked to pulmonary fibrosis.