Design, synthesis and structure-activity relationship of a series of novel BCR-ABL inhibitors / 中国药科大学学报

@#Abstract: In this study, molecular skeleton I N-phenylindoline-5-formamide was obtained by optimizing the structure of the existing allosteric BCR-ABL inhibitor asciminib. Based on this molecular skeleton, compounds 1-12 were designed and synthesized assisted by molecular docking. After characterizing their structures using ESI-MS and NMR, the anti-BCR-ABL1-dependent Luc-Ba/F3 cell proliferation activity of the target compounds in vitro was determined by CCK-8 assay. Finally, highly active lead compound 1 was screened out. For high clearance rate and short half-life period exposed in subsequent druggability evaluation, its druggability was optimized by introducing hydrophilic groups. Afterwards, compounds 13-22 were designed and synthesized. Compound 17 presented high cell inhibitory activity, low clearance rate and long half-life, and is expected to be used as a clinical candidate for further evaluation of biological activity and druggability.

Mechanisms of recombinant adenovirus-mediated SD-HA fusion protein proliferation inhibition and induced apoptosis of K562 cells / 中华血液学杂志

Objective: To investigate whether fusion protein SD-HA could regulate its downstream signaling molecule activity by competing with the phospho-BCR-ABL Y177 site, and its mechanisms to inhibit proliferation and induce apoptosis of K562 cells. Methods: Co-immunoprecipitation interaction technology analysis of fusion protein SD-HA functioned by potently binding to the phospho-BCR-ABL Y177 site, Ras, MAPK and Akt activities were observed in the Ad5F35-SD-HA-treated cells. Western blot analyses of SD-HA fusion protein on cell membrane receptor pathway to death cascade caspase-8, caspase-3 and PRAP were performed. Results: Exploration into the underlying mechanisms revealed that Ad5F35-SD-HA infection functioned by binding to the phospho-BCR-ABL Y177 site, which lead to a complex with Grb2. competitively disrupted the Grb2 SH2-phospho-BCR-ABL Y177 formation. The fusion protein SD-HA could reduce the activation of Ras and phosphorylation of MAPK (p-MAPK) and the expression level of p-ELK, inhibition of Ras-MAPK signaling pathway; SD-HA fusion protein could reduce p-Akt and Akt substrate p-GSK with inhibition of PI3K-Akt signaling pathway, thereby inhibiting the proliferation of K562 cells. Caspases-8-induced apoptosis signal could be activated by DED protein binding to DED domain of precursor caspases-8. Conclusions: The strategy of fusion protein SD-HA inhibiting-Y177 BCR-ABL and Grb2 binding could be used as a novel entry point for the treatment of chronic myeloid leukemia.

Mechanisms of recombinant adenovirus-mediated SD-HA fusion protein proliferation inhibition and induced apoptosis of K562 cells / 中华血液学杂志

Objective@#To investigate whether fusion protein SD-HA could regulate its downstream signaling molecule activity by competing with the phospho-BCR-ABL Y177 site, and its mechanisms to inhibit proliferation and induce apoptosis of K562 cells.@*Methods@#Co-immunoprecipitation interaction technology analysis of fusion protein SD-HA functioned by potently binding to the phospho-BCR-ABL Y177 site, Ras, MAPK and Akt activities were observed in the Ad5F35-SD-HA-treated cells. Western blot analyses of SD-HA fusion protein on cell membrane receptor pathway to death cascade caspase-8, caspase-3 and PRAP were performed.@*Results@#Exploration into the underlying mechanisms revealed that Ad5F35-SD-HA infection functioned by binding to the phospho-BCR-ABL Y177 site, which lead to a complex with Grb2. competitively disrupted the Grb2 SH2-phospho-BCR-ABL Y177 formation. The fusion protein SD-HA could reduce the activation of Ras and phosphorylation of MAPK (p-MAPK) and the expression level of p-ELK, inhibition of Ras-MAPK signaling pathway; SD-HA fusion protein could reduce p-Akt and Akt substrate p-GSK with inhibition of PI3K-Akt signaling pathway, thereby inhibiting the proliferation of K562 cells. Caspases-8-induced apoptosis signal could be activated by DED protein binding to DED domain of precursor caspases-8.@*Conclusions@#The strategy of fusion protein SD-HA inhibiting-Y177 BCR-ABL and Grb2 binding could be used as a novel entry point for the treatment of chronic myeloid leukemia.

Screening and characterization of aptamers of human chronic myeloid leukemia (CML) fusion protein BCR-ABL and its structure analysis / 中国免疫学杂志

Objective:To screen and characterize aptamers against BCR-ABL fusion protein.Methods:A 90bp single stranded DNA( ssDNA) random library was subjected to 13 rounds of selection against BCR-ABL fusion protein by systematic evolution of ligands by expotential enrichment ( SELEX ) method, the selected aptamers were cloned and sequenced.The primary sequences and structure of aptamers were analyzed by Clustal W and DNA Folding Sever and the percentage of the ssDNA pool bound to BCR-ABL core protein were determinated.Results: after 13 rounds selection, the percentage of ssDNA pool bound to BCR-ABL fusion protein increased from 0.3%to 47.1%,the results showed that affinities of the Aptamers were different,the second structure analysis revealed possible stem-loops for binding to BCR-ABL fusion protein,the affinity of aptamer A2 to BCR-ABL fusion protein was highest with Kd values as low as 72 nmol/L.Conclusion:Aptamers against BCR-ABL fusion protein has been identified by SELEX methods from a 90 bp single stranded DNA library.And provide certain reference for the clinical treatment of chronic myelogenous.

Antiproliferation Effect of Beta-TrCP Ubiquitin Ligase Mediated BCR-ABL Protein Degradation in Leukemia K562 Cells / 中国肿瘤临床

Objective: The BCR-ABL fusion gene induced by reciprocal translocation of t (9; 22) (q34; q11) plays an important role in the pathogenesis of chronic myeloid leukemia (CML). Using recombinant ade-noviruses carrying the N-terminal oligomerizaton domain (OD) of the BCR/ABL and chimeric ubiquitin ligase β-TrCP, this study was to investigate the effect of the targeted degradation of oncoprotein BCR-ABL by Ubiqui- tin-Proteasome System on the proliferation of leukemia call line K562. Methods: The recombinant adenovirus-es carrying wild-type β-TrCP gene (Ad5β-TrCP-OD-HA), mutational β-TrCP gene (Ad5 A F-TrCP-OD-HA)and green fluorescent protein gene (Ad5GFP)were amplified in 293 calls and co-infected into K562 cells respec- tively. The rates of infection were analyzed by flow cytometry (FCM). Recombinant protein and BCR-ABL ex-pression was detected by Western blot. Cell proliferation was determined by cell counting and methylcellu- cose clonal cell culture. Cell cycle was observed through FCM. Untreated K562 cells were used as blank con-trols. Result: The leukemia K562 cell lines with exogenous recombinant β-TrCP-OD-HA and F-TrCP-OD-HA gene were established. The infection rates in the three groups were over 66.4% and recombinant protein sus-tained to be expressed. Ad5β-TrCP-OD-HA down-regulated the expression of BCR-ABL and inhibited prolifer-ation of K562 cells. FCM showed that the percentage of cells at S phase was decreased to 10.88%±2.42%, while that of cells at G_0/G_1 was increased to 85.6%±5.61%, with a significant difference (P<0.05). No changes were found in the cell cycle in groups of Ad5 △ F-TrCP-OD-HA and Ad5GFP. Conclusion: There is sustained ex-pression of recombinant β-TrCP-OD-HA protein in K562 cells infected by recombinant adenovirus.β-TrCP-OD-HA could inhibit the proliferation and clonogenicity of K562 cells through targeted degradation of oncoprotein BCR-ABL and arresting the progression of call cycle.