Discovery And Anti-tumor Effects Research Of PIN1 Degraders And SHP1 Agonists

Phosphorylation is one of the most important post-traslational modifications,which is required for the initiation,conduction and termination of multiple cellular signaling and is essential for biological processes such as cell proliferation,metabolism and survival.This dynamic modification is tightly regulated by protein kinases and protein phosphatases,and the disturbance of phosphorylation regulation is the root of many pathological conditions including cancer,metabolic diseases.Further post-post translational modifications such as isomerization regulation have drawn attention increasingly.Therefore,the regulation of conformation and phosphorylation level of proteins plays an important role in the regulation of cellular processes and is an important strategy for drug development.In the view of the important central signaling mechanism of phosphorylation regulation,this study respectively targeted peptidyl-prolyl cis-trans isomerase PIN1 which regulates the isomeration of phosphorylated proteins and protein phosphatase SHP1,which regulates protein phosphorylation to discover novel active molecules.PIN1 is the only member of peptidyl-prolyl cis-trans isomerase family that can recognize p Ser/Thr-Pro motif and catalyze cis/trans isomeration.PIN1 was reported to activate>50oncogenes and down-regulate>20 tumor supressors to expand its oncogenic pathway,which is a potencial anti-tumor target.However,the development of PIN1 small molecule inhibitors is limited to poor membrane permeability and selectivity.PROTAC technology targeting protein degradation is suitable for the difficult-to-drug targets,so in the first part,we carried out the development of PROTAC for PIN1-targeted degradation.A total of 50 PIN1-PROTAC molecules were screened for PIN1 degradation on MV-4-11,and P1D-34 was obtained.P1D-34 could degrade PIN1 in a dose-and time-dependent manner with degradation DC₅₀ at 177n M.And the degradation of PIN1 induced by P1D-34 depends on CRBN-ubquitin-proteosome system.Compared with PIN1 inhibitor Sulfopin,P1D-34 showed better cellular proliferative inhibition activity against AML cell lines,induced cell apoptosis and cell cycle arrest.Because of the down-regulation of Mcl-1,we also proposed the strategy of combining P1D-34 with Bcl-2 inhibitor ABT199 to sensitize ABT199’s activity against AML.We further investigated the mechanism of PIN1 cell function based on transcriptopic analysis.We found that P1D-34 persistently upregates the level of intracellular ROS and induces ROS-dependent DNA damage and apoptosis.On the othe hand,P1D-34 down-regulated UPR pathway which indicates the potential association between PIN1 and UPR pathway.When combined with glucose metabolic inhibitor 2-DG,the self-protection of cell under stress was destroyed and the cell death can be synergically promoted.SHP1 is a tumor suppressor,and targeting SHP1 activation to inhibit p STAT3 pathway has been shown to be a effective anti-tumor strategy.On the other hand,we carried out the SHP1-agonists synthesis and screening under the basis of previous research.Through activation tests,we found 11 compounds that can effectively activate SHP1.After evaluating proliferativeinhibition activity of related compounds on multiple cell lines,we discovered several potent compounds with certain activity against tumor cells.The mechanism of action and sensitive cell phenotype remained to be explored.In conclusion,we obtained a novel PIN1 degrader P1D-34,and provided a powerful tool for futher exploration of PIN1.On the other hand,we discovered several effective SHP1agonists,providing data basis for further research of structure-activity relationship and drug development targeting SHP1 activation.