The senescent fibroblasts prepared from IPF patient-derived cells showed increased expression of arachidonate 5-lipoxygenase (ALOX5) but no elevation of the enzymes involved in the synthesis of prostaglandins such as PTGS2 (COX-2), PTGDS, and PTGES [81]. Here, PTGS2 is linked to idiopathic pulmonary fibrosis.