ARID3A is a transcription factor that plays critical roles in hematopoietic cell differentiation, immune regulation, and metabolic control. In normal hematopoiesis, ARID3A promotes megakaryocytic differentiation in concert with GATA1 and mediates TGFβ-induced apoptosis and cell cycle arrest 1. The protein functions as a tumor suppressor in acute megakaryoblastic leukemia, where its repression by miR-125b blocks differentiation and promotes leukemogenesis 1. ARID3A also regulates B-cell function and autoimmunity, with increased expression in systemic lupus erythematosus patients correlating with disease activity and interferon-alpha production in B lymphocytes 23. Beyond immune function, ARID3A controls metabolic processes by transcriptionally regulating glycolytic enzymes like ENO2, influencing macrophage polarization in atherosclerosis 4. In pancreatic cancer, ARID3A enhances chemoresistance by transcriptionally inhibiting PTEN, leading to suppression of ferroptosis through the PTEN-GPX4 axis 5. Additionally, ARID3A contributes to intestinal barrier dysfunction in obesity by enhancing miR-101a-3p expression, which destabilizes tight junction proteins 6. Genetic variants affecting ARID3A expression are associated with primary biliary cholangitis susceptibility 7.