In summary, we provide evidence of a crucial role of HO-1 in limiting aneurysm growth by showing that HO-1 induction by heme slows AAA progression, confirming prior reports of suppression of AAA progression with statin administration, and demonstrating that the statin therapeutic mechanism likely involves the induction of HO-1 and likely independent of lipid lowering. This evidence concerns the gene HMOX1 and aneurysm.