Fodor, Michelle, Price, Edmund, Wang, Ping, Lu, Henry, Argintaru, Andreea, Chen, Zhuoliang, Glick, Meir, Hao, Huaixiang, Kato, Mitsunori, Koenig, Robert, Jonathan, LaRochelle, Liu, Gang, Mcneill, Eric, Majumdar, Dyuti, Nishiguchi, Gisele, Perez, Lawrence, Paris, Greg, Quinn, Christopher, Ramsey, Timothy, Sendzik, Martin, Shultz, Michael, Williams, Sarah, Stams, Travis, Stephen, Blacklow, Acker, Michael and Lamarche, Matthew (2018) Dual Allosteric Inhibition of SHP2 Phosphatase. ACS Chemical Biology.

Abstract

SHP2 is a cytoplasmic protein tyrosine phosphatase encoded by the PTPN11 gene involved in proliferation, differentiation, and survival. Recently we reported an allosteric mechanism of inhibition that stabilizes the auto-inhibited conformation of SHP2. SHP099 (1) was identified and characterized as a moderately potent, orally bioavailable, allosteric small molecule inhibitor. SHP099 binds to a tunnel-like pocket formed by the confluence of three domains of SHP2. In this report, we describe further screening strategies and tactics that enabled the identification of a second, distinct small molecule allosteric site of SHP2 inhibition. SHP244 (2) was identified and characterized as a weak inhibitor of SHP2 with modest thermal stabilization of the enzyme. X-ray crystallography revealed that like 1, 2 binds and stabilizes the inactive, closed conformation of SHP2 but at a distinct, unexplored binding site- a cleft formed at the interface of the N-terminal SH2 and PTP domains. Derivatization of 2 via structure-based design resulted in an increase in SHP2 thermal stabilization, biochemical inhibition, and subsequent MAPK pathway modulation. Downregulation of DUSP6 mRNA, a downstream MAPK pathway marker, was observed in KYSE-520 cancer cells. Remarkably, simultaneous occupation of both allosteric sites by 1 and 2 was possible, as characterized by cooperative biochemical inhibition experiments and X-ray crystallography. Combining an allosteric site 1 inhibitor with an allosteric site 2 inhibitor led to enhanced pharmacological pathway inhibition in cells. This work illustrates a rare example of dual targeted protein inhibition, demonstrates screening methodology and tactics to identify allosteric inhibitors, and enables further interrogation of SHP2 in cancer and related pathologies.

Item Type:	Article
Date Deposited:	20 Jan 2018 00:45
Last Modified:	20 Jan 2018 00:45
URI:	https://oak.novartis.com/id/eprint/34272