DNMT1 and pemphigus foliaceus: Furthermore, we demonstrated that DNMT1 affects MEG3 expression by mediating MEG3 promoter hypermethylation, and IL-27 inhibits DNMT1-mediated MEG3 promoter hypermethylation, thereby upregulating MEG3 expression and thus inhibiting the ERK/p38 pathway to attenuate TGF-β1-induced PF in vitro.