Notably, in a patient with drug-resistant hypercholesterolemia, serum PCSK9 concentrations surged by 15-fold, coinciding with the detection of HNF4-α overexpression, indicating that HNF4-α might also play a role in PCSK9 regulation (Lau et al., 2020). Here, PCSK9 is linked to familial hypercholesterolemia.