Loading...
Selective CDK9 Inhibition by Natural Compound Toyocamycin in Cancer Cells
Pandey, Somnath ; Djibo, Rahinatou ; Darracq, Anaïs ; Calendo, Gennaro ; Zhang, Hanghang ; Henry, Ryan A. ; Andrews, Andrew J. ; Baylin, Stephen B. ; Madzo, Jozef ; Najmanovich, Rafael ... show 2 more
Pandey, Somnath
Djibo, Rahinatou
Darracq, Anaïs
Calendo, Gennaro
Zhang, Hanghang
Henry, Ryan A.
Andrews, Andrew J.
Baylin, Stephen B.
Madzo, Jozef
Najmanovich, Rafael
Citations
Altmetric:
Genre
Journal article
Date
2022-07-08
Advisor
Committee member
Department
Permanent link to this record
Collections
Research Projects
Organizational Units
Journal Issue
DOI
http://dx.doi.org/10.3390/cancers14143340
Abstract
Aberrant transcription in cancer cells involves the silencing of tumor suppressor genes (TSGs) and activation of oncogenes. Transcriptomic changes are associated with epigenomic alterations such as DNA-hypermethylation, histone deacetylation, and chromatin condensation in promoter regions of silenced TSGs. To discover novel drugs that trigger TSG reactivation in cancer cells, we used a GFP-reporter system whose expression is silenced by promoter DNA hypermethylation and histone deacetylation. After screening a natural product drug library, we identified that toyocamycin, an adenosine-analog, induces potent GFP reactivation and loss of clonogenicity in human colon cancer cells. Connectivity-mapping analysis revealed that toyocamycin produces a pharmacological signature mimicking cyclin-dependent kinase (CDK) inhibitors. RNA-sequencing revealed that the toyocamycin transcriptomic signature resembles that of a specific CDK9 inhibitor (HH1). Specific inhibition of RNA Pol II phosphorylation level and kinase assays confirmed that toyocamycin specifically inhibits CDK9 (IC50 = 79 nM) with a greater efficacy than other CDKs (IC50 values between 0.67 and 15 µM). Molecular docking showed that toyocamycin efficiently binds the CDK9 catalytic site in a conformation that differs from other CDKs, explained by the binding contribution of specific amino acids within the catalytic pocket and protein backbone. Altogether, we demonstrated that toyocamycin exhibits specific CDK9 inhibition in cancer cells, highlighting its potential for cancer chemotherapy.
Description
Citation
Pandey, S.; Djibo, R.; Darracq, A.; Calendo, G.; Zhang, H.; Henry, R.A.; Andrews, A.J.; Baylin, S.B.; Madzo, J.; Najmanovich, R.; et al. Selective CDK9 Inhibition by Natural Compound Toyocamycin in Cancer Cells. Cancers 2022, 14, 3340. https://doi.org/10.3390/cancers14143340
Citation to related work
MDPI
Has part
Cancers, Vol. 14, Iss. 14
ADA compliance
For Americans with Disabilities Act (ADA) accommodation, including help with reading this content, please contact scholarshare@temple.edu