FOXO3 and acne: Isotretinoin/ATRA-mediated upregulation of p53 in isotretinoin-treated acne patients may also be the underlying mechanism enhancing the expression of pro-apoptotic effectors including the p53-responsive genes FOXO1 [23], FOXO3A [23, 25] and TNFSF10 [26] promoting sebocyte apoptosis [26, 50, 54, 57].