Tin Protoporphyrin IX dichloride (NSC 267099, SnPPIX, Sn-Protoporphyrin) is a potent inhibitor of heme oxygenase-1 (HO-1), reduces ozone-induced pulmonary inflammation and BAL cell necrosis, highlighting its protective role. It also sensitizes pancreatic ductal adenocarcinoma (PDAC) tumors to chemotherapy in a mouse model, suggesting its potential for PDAC treatment.