Riboprine is a natural purine nucleoside analog (mainly a phytochemical metabolite/plant hormone) investigated for its potential various antineoplastic/antiproliferative, proapoptotic, neuroprotective, and antiangiogenic activities [38], while forodesine is a very potent synthetic and unique highly selective transition-state analog inhibitor of purine nucleoside phosphorylase (PNP), approved and used recently for the effective treatment of relapsed/refractory peripheral T-cell lymphoma [39]. The gene discussed is PNP; the disease is peripheral T-cell lymphoma, not otherwise specified.