Figure 2.

miRNAs involved in both keratinocyte differentiation and proliferation depending on their expression. Upregulation of miR-125b stimulates keratinocyte differentiation via suppression of both p63 and Notch1 expression, whereas its downregulation promotes keratinocyte proliferation by targeting fibroblast growth factor receptor 2 (FGFR2) or AKT serine/threonine kinase 3 (AKT3). Downregulation of miR-146a facilitates keratinocyte proliferation by activating epidermal growth factor receptor (EGFR), whereas its upregulation promotes terminal differentiation of keratinocytes by suppressing EGFR. Downregulation of miR-181a promotes keratinocyte proliferation by targeting Kirsten rat sarcoma 2 viral oncogene homolog (KRAS). However, the increased expression of miR-181a by high calcium or UVA irradiation is associated with keratinocyte differentiation.