(A-B) Principal component analysis based on circRNA expression levels in individual patients (A) and mean circRNA expression levels between patients (B) from non-lesional and paired lesional psoriasis skin before (L D0) and after 4 (L D4), 14 (L D14), 42 (L D42), and 84 (L D84) days of treatment. (C) Heatmap with unsupervised hierarchical clustering of mean circRNA expression (as z-score of log-transformed values) between patients from non-lesional and paired lesional psoriasis skin dependent on the day of treatment. (D-F) MA plots depicting changes in circRNA and mRNA levels between lesional D0 skin in contrast to non-lesional skin (D), as well as D4 (E) and D14 (F) in contrast to D0 lesional skin. Depicted are the normalized mean expression relative to the log2 fold change (log2FC); n(NL, L D4, L D14, and L D43) = 14, n(L D0) = 13, and n(L D84) = 12. All mRNAs are labelled (FUS, HNRNPL, DHX9, ADAR, and QKI).