-PNP inhibitors stabilize purine nucleosides (16)-PNP inhibitors promote germinal center reactions by stabilizing the TLR7 ligand guanosine (10)-Forodesine is approved for the treatment of T Cell lymphoma (Japan) (102, 107)-PNP inhibition is synthetic lethal with SAMHD1 inactivation (10, 109). Here, PNP is linked to T-cell non-Hodgkin lymphoma.