Emerging roles of protein arginine methyltransferase in multiple myeloma

Multiple myeloma (MM) is a cancer of plasma cells characterized by the clonal expansion of abnormal plasma cells in the bone marrow. These malignant cells overcrowd the bone marrow, disrupt normal hematopoiesis, and produce excessive amounts of immunoglobulins, leading to severe clinical manifestations. Despite significant advancements in treatment, relapsed/refractory MM remains incurable. Protein arginine methylation, catalyzed by protein arginine methyltransferases (PRMTs), is a critical post-translational modification involved in regulating various cellular processes. Aberrant expression of PRMTs has been strongly linked to poor prognosis in many cancers, including MM. Among the PRMT family, PRMT1, PRMT4 (CARM1), and PRMT5 have emerged as potential therapeutic targets for MM. This review will first explore the expression patterns of PRMTs in MM and assess their association with disease prognosis. We will then provide a comprehensive overview of the functions of these PRMTs in MM pathology, discuss the development of PRMT inhibitors currently being evaluated in clinical trials, and offer insights into the potential of targeting PRMTs for MM treatment in clinical settings.