Project Details
Projekt
Synergistic PDAC cell ablation by inhibiting CDKs and histone demethylases
Applicant
Professor Dr. Matthias Dobbelstein
Subject Area
Gastroenterology
Term
since 2020
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 426671079
We will test the hypothesis that inhibitors of cyclin dependent kinase 4 (CDK4) or MDM2 can eliminate PDAC cells and tumors in synergy with inhibitors of histone demethylases belonging to the KDM2 class. This hypothesis addresses a drug synergy, similar to our research during the first funding period (Ewers et al., 2021). It is based on our previous findings that the elimination of KDM2 genes perpetuates the cell cycle arrest imposed by inhibitors of CDK4 or MDM2. Mechanistically, the cell cycle is arrested by CDK4 inhibition, or by activation of p53 and its target gene product, the endogenous CDK inhibitor p21/CDKN1A. Under most circumstances, this arrest is only transient. Simultaneously interfering with KDM2 activity, however, permanently precludes further proliferation. We are now planning to determine the genetic tumor cell specificities that determine the degree of this drug synergy, comparing PDAC-derived cell lines, patient-derived cells and organoids of the CRU5002 cohort, in cooperation with CP1. To clarify the mechanism(s) of drug synergy, we are modeling KDM2 inhibitors by eliminating their targets through CRISPR-mediated gene knockout. Transcriptome analyses already revealed that antagonizing KDM2s reduces the expression of E2F target genes. Along this line, we identified a component of the “dimerization partner, RB-like, E2F and multi-vulval class B” (DREAM) complex, which represses these genes, as required for the drug synergy. Now, we will assay the genome-wide chromatin accessibility and histone methylation patterns, as well as the association of DREAM complex members with their target gene promoters, upon treatment with the inhibitors, together with Researchers from subproject SP5 and with expert support on bioinformatics (CP2). Furthermore, we will address the impact of each drug on replication stress and mitotic failure, in cooperation with Researchers from subproject SP6. The impact of mutant p53 on the susceptibility of cells towards these inhibitors will be investigated together with Researchers from subproject SP2. Finally, we are going to validate the synergism on in vivo models of PDAC, in cooperation Researchers from subproject CP1.
DFG Programme
Clinical Research Units
