PIK3R1 (Phosphoinositide-3-Kinase, Regulatory Subunit 1): PIK3R1 is a gene that encodes a regulatory subunit of phosphoinositide 3-kinase (PI3K), a crucial component in signaling pathways that control cell growth, proliferation, and survival. Mutations in PIK3R1 are associated with various cancers and are targets for cancer therapies. Additionally, it plays a role in insulin signaling and is linked to diabetes and metabolic syndromes.