Furthermore, we showed that the addition of PGI2 analogue (beraprost sodium) and the inhibition of CS extract- and hypoxia-induced COX-2-derived TXA2 production by COX-2 inhibitor (celecoxib) can restore the balance of prostanoids and help reduce pulmonary vascular remodelling in COPD-associated PH via the inhibition of PASMC and PAEC proliferation. This evidence concerns the gene PTGS2 and chronic obstructive pulmonary disease.