2010). It has been reported that an EP4 antagonist ONO‐AE3‐208 attenuated angiotensin II‐induced AAA in ApoE−/− mice (Cao et al. 2012; Yokoyama et al. 2012), suggesting that inhibition of EP4 signaling has the potential to attenuate AAA progression. Here, PTGER4 is linked to triple-A syndrome.