PCSK9 and psoriasis: Recently, Krahel et al. found that proprotein convertase subtilisin/kexin type 9 (PCSK9) was associated with lipid disturbances and could be a novel biomarker in psoriasis, and that three months of MTX treatment remarkably reduced the PCSK9 levels in psoriasis patients, indicating that MTX might be considered as a new treatment approach for psoriasis [9].