title: Inhibitors of the enzyme purine nucleoside phosphorylase as potential therapy for psoriasis.
abstract: Purine nucleoside phosphorylase (PNP) is one of the enzymes comprising the purine salvage pathway , and is responsible for the catalysis of the reversible phosphorolytic cleavage of purine ribonucleosides and 2'-deoxyribonucleosides. The pivotal role of PNP in T-cell proliferation has been demonstrated in patients with inherited PNP deficiency, where T-cell levels may be 1-3% of normal. This observation helped establish the critical role of PNP in T-cells and provided a rationale for developing inhibitors of PNP. Inhibitors of PNP may be useful for treating a variety of T-cell related autoimmune diseases including psoriasis, rheumatoid arthritis and Crohn s disease and T-cell cancers. In this manuscript, the x-ray crystal structure of the PNP enzyme is described. Results of a structure-based drug design program aimed at designing small-molecule inhibitors of PNP are also described. Of the many classes of compounds synthesized, studied and reviewed, only one, the 3-pyridinylmethyl-9-deazaguanine (BCX-34, 39) analog has been used in clinical trials. Both topical and oral formulations of BCX-34 were studied in psoriatic patients and the results of these clinical trials are described.
authors.affiliation: BioCryst Pharmaceuticals, Inc., 2190 Parkway Lake Drive, Birmingham, AL 35244, USA. pmorris@biocryst.com
authors.forename: P E
authors.initials: PE
authors.lastname: Morris
authors.forename: G A
authors.initials: GA
authors.lastname: Omura
mesh_terms: D015195:Drug Design; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D006147:Guanine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D008958:Models, Molecular; D011565:Psoriasis / Q000188:drug therapy* / Q000201:enzymology; D011683:Purine-Nucleoside Phosphorylase / Q000037:antagonists & inhibitors* / Q000502:physiology; D013329:Structure-Activity Relationship
chemical_list: D004791:Enzyme Inhibitors; D006147:Guanine; C104194:peldesine; D011683:Purine-Nucleoside Phosphorylase