However, the non-canonical pathways related to the effects of atorvastatin and ezetimibe on hypercholesterolemia-induced pulmonary fibrosis, including phosphatidylinositol 3-kinase (PI3K)/Akt, mitogen-activated protein kinases (MAPKs), cell division control protein 42 homolog (CDC42)/Rac, and Rho-like GTPase, as well as follistatin-like 1 (FLST1) need further investigation. Here, CDC42 is linked to familial hypercholesterolemia.