Subsequently, cell growth inhibition experiments using two HTLV-1-infected cell lines (HTLV-1 oncogenic protein Tax-positive MT2 and HUT102), five ATL cell lines (Tax-positive KOB and SU9T-01, Tax-negative KK1, SO4, and ED), and three T-ALL cell lines (Jurkat, MOLT4, and MKB1) were performed via two SAM-competitive inhibitors (CMP5 and HLCL61), which selectively and reversibly bind to the active site of PRMT5 and inhibit PRMT5-mediated arginine methylation [28,29]. Here, PRMT5 is linked to acute lymphoblastic leukemia.