Cyclin-Dependent Kinase 9 Degradation for Disrupting Transcriptional Addiction in Cancer
Main Article Content
Abstract
Transcriptional addiction describes the dependence of cancer cells on sustained RNA polymerase II (Pol II)-driven gene expression to maintain short-lived survival proteins, including MYC and MCL-1 (myeloid cell leukemia-1). Cyclin-dependent kinase 9 (CDK9), the catalytic kinase within the positive transcription elongation factor b (P-TEFb), controls the transition from promoter-proximal pausing to productive transcriptional elongation and is therefore a central vulnerability in tumors driven by amplified oncogenic transcription. This review provides a comprehensive translational survey of the CDK9-targeting landscape, spanning biology, inhibition, and protein degradation. It is organized around the thesis that targeted CDK9 protein degradation represents the most mechanistically complete strategy for disrupting transcriptional addiction in cancer. Although kinase inhibitors established proof of concept, their effects can be limited by transient target suppression, compensatory pathway reactivation, and incomplete disruption of non-catalytic CDK9 functions. Targeted protein degraders offer a mechanistically distinct approach by eliminating the CDK9 protein pool and suppressing both catalytic and scaffold functions. Combination strategies targeting anti-apoptotic proteins, bromodomain readers, and DNA damage response pathways may further exploit transcriptional vulnerabilities, positioning CDK9-directed protein degradation as a mechanistically grounded framework for precision oncology in both hematological and solid tumors.
Keywords:
CDK9, transcriptional addiction, targeted protein degradation, MYC, MCL-1, cancer therapy, proteasome, ubiquitin
Article Details
How to Cite
PAULA, Mario Di; KASHALA, Oscar.
Cyclin-Dependent Kinase 9 Degradation for Disrupting Transcriptional Addiction in Cancer.
Medical Research Archives, [S.l.], v. 14, n. 6, june 2026.
ISSN 2375-1924.
Available at: <https://esmed.org/MRA/mra/article/view/7516>. Date accessed: 02 july 2026.
doi: https://doi.org/10.18103/mra.v14i6.7516.
Section
Review Articles
The Medical Research Archives grants authors the right to publish and reproduce the unrevised contribution in whole or in part at any time and in any form for any scholarly non-commercial purpose with the condition that all publications of the contribution include a full citation to the journal as published by the Medical Research Archives.
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