title: The structure-activity relationship of the series of non-peptide small antagonists for p56lck SH2 domain.
abstract: The antagonists for the SH2 domain are regarded as novel therapeutic candidates for cancer, autoimmune disease, and chronic inflammatory disease. Previously, we identified rosmarinic acid (alpha-o-caffeoyl-3,4-dihydroxyphenyl-lactic acid; RosA) from Prunella vulgaris as an antagonist for the p56lck SH2 domain by screening natural products. RosA not containing phosphotyrosine surrogate had a considerable inhibitory activity for T-cell antigen receptor (TCR)-induced interleukin (IL)-2 expression, and subsequent T-cell proliferation in vitro cell assay. To investigate the structure-activity relationship of RosA and to identify a novel p56lck SH2 antagonist with more potent in vitro T-cell inhibitory activity, we synthesized several analogs of RosA by using rational design. All synthesized compounds were tested in vitro binding activity for the SH2 domain and in vitro T-cell inhibitory activity. All four hydroxyl groups of RosA were essential for binding with the p56lck SH2 domain and T-cell inhibitory activity. Unexpectedly, conformationally less constrained analogs 4 and 9 showed a more potent binding affinity for the SH2 domain than that of RosA, and chirality of the analog did not play an important role in protein binding. We successfully identified several RosA analogs with a more potent T-cell inhibitory activity than that of RosA. Overall results revealed important structural requirements of the p56lck SH2 antagonists for in vitro T-cell inhibitory activity and in vitro protein binding activity.
authors.affiliation: Signal Transduction Laboratory, Mogam Biotechnology Research Institute, 341 Pojung-Ri, Koosung-Myun, Yongin-City, Kyunggi-Do, 449-910, Republic of Korea.
authors.forename: See-Hyoung
authors.initials: SH
authors.lastname: Park
authors.forename: Hyun-Sik
authors.initials: HS
authors.lastname: Oh
authors.forename: Mi-Ae
authors.initials: MA
authors.lastname: Kang
authors.forename: Hyeongjin
authors.initials: H
authors.lastname: Cho
authors.forename: Joshi Bishnu
authors.initials: JB
authors.lastname: Prasad
authors.forename: Jonghwa
authors.initials: J
authors.lastname: Won
authors.forename: Keun-Hyeung
authors.initials: KH
authors.lastname: Lee
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D002934:Cinnamates / Q000737:chemistry* / Q000494:pharmacology; D053630:Depsides / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D019169:Jurkat Cells; D015842:Serine Proteinase Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D013601:T-Lymphocytes / Q000187:drug effects*; D018909:src Homology Domains / Q000187:drug effects*; D000097123:Rosmarinic Acid
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002934:Cinnamates; D053630:Depsides; D015842:Serine Proteinase Inhibitors; D000097123:Rosmarinic Acid