| Autor: |
Chao Zhang, Qing-Xi Yue, Shan-Ling Liu, Feng-Hou Gao, Quan-Wu Zhang, Hong–Liang Zhang, Zhen Liu |
| Rok vydání: |
2021 |
| Předmět: |
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| DOI: |
10.21203/rs.3.rs-531206/v1 |
| Popis: |
Background Cyclin-dependent kinases (CDKs) are regarded as promising targets for cancer therapy. CDK2 and CDK4 are the core molecules in the G0 and G1 phases of the cell cycle. Exploring the molecular mechanism of CDK2 and CDK4 protein degradation will provide clues and solutions to control the G0 and G1 phases in tumor cells. Methods The expression levels of CDK2 and CDK4 were assessed by Western blotting and qRT-PCR. Cell viability, cell proliferation and growth were evaluated in CCK-8 and flow cytometric analysis. Protein interactions were analysed by immunoprecipitation and immunofluorescence methods. Results NVP-BEZ235 induced neuroblastoma cell arrest at the G0/G1 phase, and proliferation inhibition was associated with a significant reduction in the CDK2 and CDK4 proteins in a dose-dependent manner at nanomolar concentrations. Surprisingly, we found that the NVP-BEZ235-induced downregulation of CDK2 and CDK4 was dramatically rescued by autophagy-lysosome inhibitors. Additionally, the blockade of autophagy-related genes contributed to the remarkable rescue of CDK2 and CDK4, which thus strikingly improved NVP-BEZ235-induced G0/G1 arrest and growth inhibition of neuroblastoma cells. Subsequently, we observed the first evidence that NVP-BEZ235 induced the interaction of p62/SQSMT1 with CDK2 or CDK4 and the autophagic degradation of CDK2 and CDK4 in a cathepsin B-dependent manner. Analogous results regarding autophagy and the antiproliferative effects of NVP-BEZ235 were observed in a neuroblastoma xenograft mouse model in vivo. Conclusions These results not only established the pivotal role of the autophagy pathway in G0/G1 cell cycle-related protein turnover but also suggest the potential application of NVP-BEZ235 for cancer treatment by modulating elements of the autophagic machinery to promote degradation of G0/G1 cell cycle-related proteins. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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