PTGS2 and lung cancer: Lung cancer cell lines (A549 and H460), treated with CBD IC50 (3.47 and 2.80 μM), respectively, activated COX-2- and PPARγ-dependent apoptosis because the use of COX-2 (NS-398) and PPAR-γ (GW9662) inhibitors removed the cytotoxic and apoptotic effect of CBD.