POU2AF1 is a transcriptional coactivator that associates with POU domain-containing transcription factors, primarily POU2F1/OCT1 and POU2F2/OCT2, to enhance their promoter activity. It is essential for B-cell antigen responses and germinal center formation, and regulates IL-6 expression in B cells. Recent evidence suggests POU2AF1 has broader roles beyond B-cell biology: it promotes adipogenesis in mesenchymal stem cells through HDAC1 inhibition 1, and restricts Th2 cell differentiation by modulating GATA3-dependent IL-4 and IL-13 production 2. POU2AF1 is dysregulated in multiple malignancies. In B-cell lymphomas and multiple myeloma, tumors depend on POU2AF1-POU2F1/2 complexes and are sensitive to mSWI/SNF chr11 remodeling complex inhibition, with proteolysis-targeting chimera degraders of mSWI/SNF ATPases evicting POU2AF1 from chr11 and reducing downstream signaling 3. In hepatocellular carcinoma, POU2AF1 has emerged as a candidate therapeutic target based on network analysis 4. POU2AF1 was also identified as a hub gene in rheumatoid arthritis, associated with the IL-6/JAK/STAT3 inflammatory pathway 5, and its expression is downregulated in established RA patients 6. These diverse disease associations highlight POU2AF1 as a multifunctional regulator with relevance to immune homeostasis and malignant transformation.