Development of a novel class of B-RafV600E-selective inhibitors through virtual screening and hierarchical hit optimization†
Xiangqian Kong,Jie Qin,Zeng Li,Adina Vultur,Linjiang Tong,Enguang Feng,Geena Rajan,Shien Liu,Junyan Lu,Zhongjie Liang,Mingyue Zheng,Weiliang Zhu,Hualiang Jiang,Meenhard Herlyn,Hong Liu,Ronen Marmorstein
Abstract
Oncogenic mutations in critical nodes of cellular signaling pathways have been associated with tumorigenesis and progression. The B-Raf protein kinase, a key hub in the canonical MAPK signaling cascade, is mutated in a broad range of human cancers and especially in malignant melanoma. The most prevalent B-RafV600E mutant exhibits elevated kinase activity and results in constitutive activation of the MAPK pathway, thus making it a promising drug target for cancer therapy. Herein, we describe the development of novel B-RafV600E selective inhibitors via multi-step virtual screening and hierarchical hit optimization. Nine hit compounds with low micromolar IC50 values were identified as B-RafV600E inhibitors through virtual screening. Subsequent scaffold-based analogue searching and medicinal chemistry efforts significantly improved both the inhibitor potency and oncogene selectivity. In particular, compounds 22f and 22q possess nanomolar IC50 values with selectivity for B-RafV600Ein vitro and exclusive cytotoxicity against B-RafV600E harboring cancer cells.
