FOXO1 and acne: Importantly, the transcription factor p53, known as the guardian of the genome [21, 22], is critically involved in the expression of FoxO1 [23], FoxO3a [24, 25], tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) [26], tumour necrosis factor receptor superfamily member 10B (TNFRSF10B; death receptor 5) [23], repression of AR [27] and IGF1R [28], and suppression of IGF-1-AKT-mTORC1 signalling [28–31], thus linking crucial transcriptional and nutrigenomic regulators involved in acne pathogenesis.