For instance, in asthma, the effects of PGE2 or different EP receptors agonists can have beneficial effects on bronchial SMC, such as inhibition of proliferation through EP2 and EP4 receptors (Zaslona and Peters-Golden, 2015) and relaxation via EP2 in mice and EP4 in humans (Buckley et al., 2011; Benyahia et al., 2012). Here, PTGER2 is linked to asthma.