Tankyrase 1 And BRD4 Targeted Anti-cancer Hit Compound Discovery And Evaluation

In our previous work, an NMR-based fragment library had been successfully setup. And in this thesis, the hit fragment compounds that bind to the target proteins Tankyrase 1 and BRD4 were screened out from the fragment library by using 1D NMR experiments including CPMG and STD. To further confirm the binding and obtain the mapping information for the interactions between the hits and the target proteins, 2D [1H, 15N] HSQC spectra were acquired by using the 15N-labeled protein samples with or without the presences of the hit compounds. Meanwhile, X-ray diffraction techniques were subjected to solve the structures of the target proteins complexed with the hit compounds, and the achieved structural information were used to explain the structure-activity relationship of the hit compounds.For Tankyrase 1, a total number of 10 hits with unreported novel scaffolds were screened out by using 1D CPMG and STD experiments. Then, the crystal structure of tankyrase 1 complexed with one of the hit compounds 1-A4 was determined.For BRD4, a total number of 10 hits were screened out from the fragment library by using 1D CPMG, 1D STD and 2D HSQC experiments. Eight compounds from the ten hits have unreported novel scaffolds for the down-modulation of BRD4. The inhibition activities of four hit compounds with novel scaffolds were characterized to have the IC50 value in the range of 100~260 ?M, which showed the potential for further BRD4-targeted hit-to-lead optimization. The binding interactions of four potential candidate compounds were then unravelled by using 2D NMR and X-ray crystallography techniques. Two compounds(compound 1 and compound 2) in the four candidates share a common quinazolin core structure, and bind to BRD4(44-168) in a non-acetylated lysine mimetic mode. Since non-acetylated lysine mimetic inhibitors may have the capability to be selective BRD4 inhbitors, our finding provide a good start for developing novel types of BRD4 inhibitors.