PCSK9 and Pseudoxanthoma elasticum: Kuzaj et al. found dysregulations in the lipid metabolism of primary human dermal fibroblasts of PXE patients, as there is increased activity of HMG-COA reductase, strongly elevated transcript and protein levels of proprotein convertase subtilisin/kexin type 9 (PCSK9) and a significant reduction in APOE mRNA expression, which probably give a first explanation for the positive effect of statins on PXE pathogenesis.