Discovery of Potent, Selective, and Orally Bioavailable Small-Molecule Modulators of the Mediator Complex-Associated Kinases CDK8 and CDK19.

The Mediator complex-associated cyclin-dependent kinase CDK8 has been implicated in human disease, particularly in colorectal cancer where it has been reported as a putative oncogene. Here we report the discovery of 109 (CCT251921), a potent, selective, and orally bioavailable inhibitor of CDK8 with equipotent affinity for CDK19. We describe a structure-based design approach leading to the discovery of a 3,4,5-trisubstituted-2-aminopyridine series and present the application of physicochemical property analyses to successfully reduce in vivo metabolic clearance, minimize transporter-mediated biliary elimination while maintaining acceptable aqueous solubility. Compound 109 affords the optimal compromise of in vitro biochemical, pharmacokinetic, and physicochemical properties and is suitable for progression to animal models of cancer

3D imaging of colorectal cancer organoids identifies responses to Tankyrase inhibitors

Aberrant activation of the Wnt signalling pathway is required for tumour initiation and survival in the majority of colorectal cancers. The development of inhibitors of Wnt signalling has been the focus of multiple drug discovery programs targeting colorectal cancer and other malignancies associated with aberrant pathway activation. However, progression of new clinical entities targeting the Wnt pathway has been slow. One challenge lies with the limited predictive power of 2D cancer cell lines because they fail to fully recapitulate intratumoural phenotypic heterogeneity. In particular, the relationship between 2D cancer cell biology and cancer stem cell function is poorly understood. By contrast, 3D tumour organoids provide a platform in which complex cell-cell interactions can be studied. However, complex 3D models provide a challenging platform for the quantitative analysis of drug responses of therapies that have differential effects on tumour cell subpopulations. Here, we generated tumour organoids from colorectal cancer patients and tested their responses to inhibitors of Tankyrase (TNKSi) which are known to modulate Wnt signalling. Using compounds with 3 orders of magnitude difference in cellular mechanistic potency together with image-based assays, we demonstrate that morphometric analyses can capture subtle alterations in organoid responses to Wnt inhibitors that are consistent with activity against a cancer stem cell subpopulation. Overall our study highlights the value of phenotypic readouts as a quantitative method to asses drug-induced effects in a relevant preclinical model

A novel tankyrase inhibitor, MSC2504877, enhances the effects of clinical CDK4/6 inhibitors.

Inhibition of the PARP superfamily tankyrase enzymes suppresses Wnt/β-catenin signalling in tumour cells. Here, we describe here a novel, drug-like small molecule inhibitor of tankyrase MSC2504877 that inhibits the growth of APC mutant colorectal tumour cells. Parallel siRNA and drug sensitivity screens showed that the clinical CDK4/6 inhibitor palbociclib, causes enhanced sensitivity to MSC2504877. This tankyrase inhibitor-CDK4/6 inhibitor combinatorial effect is not limited to palbociclib and MSC2504877 and is elicited with other CDK4/6 inhibitors and toolbox tankyrase inhibitors. The addition of MSC2504877 to palbociclib enhances G 1 cell cycle arrest and cellular senescence in tumour cells. MSC2504877 exposure suppresses the upregulation of Cyclin D2 and Cyclin E2 caused by palbociclib and enhances the suppression of phospho-Rb, providing a mechanistic explanation for these effects. The combination of MSC2504877 and palbociclib was also effective in suppressing the cellular hyperproliferative phenotype seen in Apc defective intestinal stem cells in vivo. However, the presence of an oncogenic Kras p.G12D mutation in mice reversed the effects of the MSC2504877/palbociclib combination, suggesting one molecular route that could lead to drug resistance

A selective chemical probe for exploring the role of CDK8 and CDK19 in human disease.

There is unmet need for chemical tools to explore the role of the Mediator complex in human pathologies ranging from cancer to cardiovascular disease. Here we determine that CCT251545, a small-molecule inhibitor of the WNT pathway discovered through cell-based screening, is a potent and selective chemical probe for the human Mediator complex-associated protein kinases CDK8 and CDK19 with >100-fold selectivity over 291 other kinases. X-ray crystallography demonstrates a type 1 binding mode involving insertion of the CDK8 C terminus into the ligand binding site. In contrast to type II inhibitors of CDK8 and CDK19, CCT251545 displays potent cell-based activity. We show that CCT251545 and close analogs alter WNT pathway-regulated gene expression and other on-target effects of modulating CDK8 and CDK19, including expression of genes regulated by STAT1. Consistent with this, we find that phosphorylation of STAT1(SER727) is a biomarker of CDK8 kinase activity in vitro and in vivo. Finally, we demonstrate in vivo activity of CCT251545 in WNT-dependent tumors

What changes of the length of stay are associated with whiteboards as lean management instruments? A retrospective timeseries analysis in two hospitals

Introduction: Whiteboards are lean management instruments that serve to govern the length of stay on hospital wards. They are implemented to bundle up-to-date patient information, to enable regular and structured interdisciplinary team meetings, to stimulate the collaboration within the team and hereby to govern the care process and improve the discharge management. The aim of this study was to investigate, whether the implementation of whiteboards was associated with a change of the length of stay. Methods: In order to answer the research question, a retrospective interrupted timeseries analysis of DRG routine data before and after implementation of whiteboards in two hospitals was performed. A total of 3,734 clinical cases covering the period January 2018 to December 2019 from one hospital (medical specialty surgery) and 54,049 clinical cases from the period July 2013 to December 2019 from the second hospital (medical specialty internal medicine) were included.Results: Comparing the average length of stay before and after (expressed as the relative difference from the statewide mean per DRG) showed no significant difference for the first hospital and a significant deterioration for the second hospital. The descriptive timeseries analysis revealed in both hospitals, that the length of stay worsened shortly after the introduction of the whiteboards, however, improved later, which meant that patients were discharged earlier. During the further course, this difference faded reaching the baseline level values. Discussion: In summary, no improvement of the length of stay could be found in a before-after comparison of the means. The descriptive timeseries analysis could partly explain these findings revealing a strong variability that reflected a short-term worsening followed by improvements, which, however, in the end did not last. This meant that patients were discharged again later. From a methodological point of view, only the timeseries perspective could yield an insight into the course of the events whereas the comparison of the averages aggregating the values could not capture the variability. From a practical point of view, it can be concluded that whiteboards can be a useful lean management instrument to govern the length of stay as the short-term improvements suggest. However, this requires the staff to continuously update the information on the board and for the entire handling to yield a tangible added value for the staff. Therefore, it seems rewarding to implement digital whiteboards to mitigate the manual effort of updating the information on the board.Einleitung: Whiteboards können als ein Instrument des Lean Managements zur Steuerung der Verweildauer auf Stationen eingesetzt werden, um aktuelle Patienteninformationen zu bündeln und in regelmäßigen strukturierten sowie interdisziplinären Besprechungen die Patientenversorgung zu steuern, die interdisziplinäre Zusammenarbeit zu optimieren und das Entlassungsmanagement zu verbessern. Das Ziel dieser Studie bestand darin, zu untersuchen, inwiefern die Einführung von Whiteboards in zwei Kliniken mit einer Veränderung der Verweildauer einherging. Methode: Um die Forschungsfrage zu beantworten, wurden retrospektive Zeitreihen aus den DRG-Routinedaten vor und nach Installation der Whiteboards aus den beiden Kliniken in einem Interrupted Time Series Design genutzt. In der einen Klinik (Chirurgie) lagen 3.734 Fälle für den Zeitraum von Januar 2018 bis Dezember 2019 und in der anderen Klinik (Innere Medizin) 54.049 Fälle für den Zeitraum Juli 2013 bis Dezember 2019 vor.Ergebnisse: In dem gemittelten Vergleich der Verweildauer (relative Verweildauerabweichung pro DRG von dem jeweiligen Verweildauermittel) konnte in der ersten Klinik kein signifikanter Unterschied zwischen den Werten vor und nach Einführung des Boards festgestellt werden. Am zweiten Klinikum zeigte sich sogar im Vorher-Nachher-Vergleich eine signifikante Verschlechterung der Verweildauer. Eine deskriptive Zeitreihenanalyse vor und nach Einführung zeigte in beiden Kliniken, dass kurz nach der Einführung der Boards sich die Verweildauer verschlechterte, anschließend jedoch verbesserte, d.h. dass die Patienten durchschnittlich früher entlassen wurden. Dieser Unterschied ging jedoch im Zeitverlauf wieder zurück.Diskussion: Zusammenfassend lässt sich festhalten, dass keine Verbesserung in der Verweildauer im Zuge der Nutzung der Whiteboards durch einen reinen Vorher-Nachher-Vergleich nachweisbar war. In der anschließenden Zeitreihenbetrachtung zeigten sich starke Schwankungen, die zunächst mit einer kurzzeitigen Verschlechterung der Verweildauer nach der Implementierung einhergingen und dann zu einer Verbesserung führten. Im Zeitverlauf verblasste der Unterschied jedoch, sodass die Patienten wieder später entlassen wurden. Methodisch zeigt sich, dass im Gegensatz zu der reinen Vorher-Nachher-Analyse erst eine Zeitreihenbetrachtung einen Einblick in das Geschehen und seine Variabilität lieferte. Für die Praxis ergeben sich folgende Implikationen: Whiteboards können als ein hilfreiches Instrument von Lean Management zur Verweildauersteuerung angesehen werden, wie die zwischenzeitlichen Verbesserungen nahelegen. Dies erfordert jedoch eine kontinuierliche, unter Einbezug der Mitarbeiter durchgeführte Pflege der Informationen und einen erkennbaren Mehrwert. Perspektivisch empfiehlt sich zudem eine Digitalisierung der Boards, um den Nachteilen wie der manuellen Pflege entgegenzuwirken

FGFR1 overexpression in non-small cell lung cancer is mediated by genetic and epigenetic mechanisms and is a determinant of FGFR1 inhibitor response

Amplification of fibroblast growth factor receptor 1 (FGFR1) in non-small cell lung cancer (NSCLC) has been considered as an actionable drug target. However, pan-FGFR tyrosine kinase inhibitors did not demonstrate convincing clinical efficacy in FGFR1-amplified NSCLC patients. This study aimed to characterise the molecular context of FGFR1 expression and to define biomarkers predictive of FGFR1 inhibitor response. In this study, 635 NSCLC samples were characterised for FGFR1 protein expression by immunohistochemistry and copy number gain (CNG) by in situ hybridisation (n = 298) or DNA microarray (n = 189). FGFR1 gene expression (n = 369) and immune cell profiles (n = 309) were also examined. Furthermore, gene expression, methylation and microRNA data from The Cancer Genome Atlas (TCGA) were compared. A panel of FGFR1-amplified NSCLC patient-derived xenograft (PDX) models were tested for response to the selective FGFR1 antagonist M6123. A minority of patients demonstrated FGFR1 CNG (10.5%) or increased FGFR1 mRNA (8.7%) and protein expression (4.4%). FGFR1 CNG correlated weakly with FGFR1 gene and protein expression. Tumours overexpressing FGFR1 protein were typically devoid of driver alterations (e.g. EGFR, KRAS) and showed reduced infiltration of T-lymphocytes and lower PD-L1 expression. Promoter methylation and microRNA were identified as regulators of FGFR1 expression in NSCLC and other cancers. Finally, NSCLC PDX models demonstrating FGFR1 amplification and FGFR1 protein overexpression were sensitive to M6123. The unique molecular and immune features of tumours with high FGFR1 expression provide a rationale to stratify patients in future clinical trials of FGFR1 pathway-targeting agents.De tre första författarna delar förstaförfattarskapetDe två sista författarna delar sistaförfattarskapet</p

Structure-Based Optimization of Potent, Selective, and Orally Bioavailable CDK8 Inhibitors Discovered by High-Throughput Screening.

The mediator complex-associated cyclin dependent kinase CDK8 regulates β-catenin-dependent transcription following activation of WNT signaling. Multiple lines of evidence suggest CDK8 may act as an oncogene in the development of colorectal cancer. Here we describe the successful optimization of an imidazo-thiadiazole series of CDK8 inhibitors that was identified in a high-throughput screening campaign and further progressed by structure-based design. In several optimization cycles, we improved the microsomal stability, potency, and kinase selectivity. The initial imidazo-thiadiazole scaffold was replaced by a 3-methyl-1H-pyrazolo[3,4-b]-pyridine which resulted in compound 25 (MSC2530818) that displayed excellent kinase selectivity, biochemical and cellular potency, microsomal stability, and is orally bioavailable. Furthermore, we demonstrated modulation of phospho-STAT1, a pharmacodynamic biomarker of CDK8 activity, and tumor growth inhibition in an APC mutant SW620 human colorectal carcinoma xenograft model after oral administration. Compound 25 demonstrated suitable potency and selectivity to progress into preclinical in vivo efficacy and safety studies