Abstract 4879: Mutation selectivity of the allosteric SHP2 inhibitor SHP099

Abstract

Abstract SHP2 (PTPN11) mediates oncogenic signaling and gain-of-function (GOF) SHP2 mutations are associated with leukemias and other types of cancer. Recently, SHP099 was identified as a novel allosteric SHP2 inhibitor that displayed high potency and selectivity to the wildtype SHP2 in vitro and inhibited protein tyrosine kinase oncogene-driven cancer cells. However, it was unclear whether SHP099 inhibits SHP2 mutants. Using SHP2 mutant-dependent TF-1 leukemia cells, we determined sensitivities of four common oncogenic SHP2 mutants to SHP099. SHP2D61Y-, SHP2A72V-, and SHP2E76K-expressing TF-1 cells were resistant, whereas SHP2E69K-expressing TF-1 cells were sensitive to SHP099 with a potency similar to that of cytokine-stimulated TF-1 cells expressing the wildtype SHP2. Consistently, SHP099 reduced active ERK1/2 and Bcl-XL and induced apoptosis of SHP2E69K-dependent TF-1 cells, but had no effects on the other SHP2 mutant cell lines. SHP2 knockout cells were unresponsive to SHP099, demonstrating specificity. Like the wildtype SHP2, SHP2E69K PTP was inhibited by SHP099 in vitro with a sub-micromolar IC50, whereas micromolar IC50s of SHP099 were observed against SHP2D61Y, SHP2A72V, and SHP2E76K. These results indicate that SHP2D61Y, SHP2A72V, and SHP2E76K mutants are resistant to SHP099 and that SHP2E69K is a SHP099-sensitive oncogenic mutant. Citation Format: Xiaojun Sun, Yuan Ren, Steven Gunawan, Peng Teng, Zhengming Chen, Harshani R. Lawrence, Jianfeng Cai, Nicholas J. Lawrence, Jie Wu. Mutation selectivity of the allosteric SHP2 inhibitor SHP099 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4879.