Die Verknüpfung von CDK6 und Extrazellulären Vesikeln

Kurzbezeichnung

CDK6 and EVs

Einrichtung Vetmeduni

Zentrum für Biologische Wissenschaften

Art der Forschung

Grundlagenforschung

Forschungsschwerpunkt

Translationale Medizin und vergleichende Medizin

Abstract

Wider research context:Intracellular and extracellular vesicles (IVs and EVs) are highly heterogeneous organelles with fundamental roles in cellular homeostasis and malignant transformation. Deregulation of vesicle biogenesis and release is described to be a feature of transformation and disease progression, including hematopoietic malignancies. Acute myeloid leukemia (AML) is a highly aggressive disease with high need of novel therapies. Interfering with vesicle biogenesis is a developing new therapeutic direction Research question:Cyclin-dependent kinase 6 (CDK6) is a crucial regulator of AML. Understanding the mechanisms initiated by CDK6 inhibition is essential to reveal therapeutic windows enabling novel combinatorial treatment strategies. We now propose to clarify the mechanism by which CDK6 regulates vesicle biogenesis and will test whether CDK6 inhibitors could play a part in combination therapies with drugs targeting vesicle biogenesis for AML patients.Approach/methods:We will analyse the effect of CDK6 kinase-dependent and -independent functions on vesicle biogenesis and in turn niche cells with human AML cell lines and primary patient samples in combination with a 3D in vitro model and PDX mouse models. We will take advantage of human AML cell lines treated with a CDK4/6 kinase inhibitor or harboring a CDK6 C-terminally tagged degrader system to rapidly degrade endogenous CDK6 and verify CDK6 specificity. We will define how CDK6 regulates vesicle biogenesis via transcriptional regulation and protein interaction by integrating ChIP-Seq, transcriptomic and phopho-proteomic data in WP1. In WP2 we will get deeper insights if CDK6 inhibition changes the AML-EV cargo and if these changes effect niche cells by establishing a 3D model with stromal, endothelial and healthy hematopoietic cells. Cells of this model will be phenotypically and functionally analysed and the transcriptomic pattern will be determined by scRNA-Seq. A combinatorial drug screen with CDK6 inhibitors and small molecules targeting vesicle biogenesis will propose novel therapeutic strategies in WP3. We will validate the results in human patient samples in vitro and in vivo. Level of originality/innovation:Studying communication of the malignant niche is key in understanding disease mechanisms and to define novel therapeutic strategies, especially for malignancies with minimal therapeutic options. EVs are one route for cell-cell interaction and influencing their regulation might present attractive novel targets. CDK4/6 kinase inhibitors are already in clinical use, however single therapy shows very limited success. Drug combinations with CDK4/6 kinase inhibitors to effect vesicle biogenesis and therefore the leukemic niche might lead to increased therapeutic success and open novel therapeutic windows for AML.