The FOXO (Forkhead box O) family consists of transcription factors involved in regulating gene expression for various cellular processes, including apoptosis, cell cycle control, antioxidant response, and energy metabolism. Family members include FOXO1, FOXO3, FOXO4, and FOXO6, which are located in both the nucleus and cytoplasm and shuttle between these compartments through phosphorylation. These transcription factors respond to signaling pathways, including insulin/IGF-1, to participate in cell fate decisions. Specific expression and mutations of these genes are associated with various diseases, such as cancer, diabetes, and neurodegenerative diseases.