Summary
The epigenome is often deregulated in cancer and treatment with inhibitors of bromodomain and extra‐terminal proteins, the readers of epigenetic acetylation marks, represents a novel ...therapeutic approach. Here, we have characterized the anti‐tumour activity of the novel bromodomain and extra‐terminal (BET) inhibitor BAY 1238097 in preclinical lymphoma models. BAY 1238097 showed anti‐proliferative activity in a large panel of lymphoma‐derived cell lines, with a median 50% inhibitory concentration between 70 and 208 nmol/l. The compound showed strong anti‐tumour efficacy in vivo as a single agent in two diffuse large B cell lymphoma models. Gene expression profiling showed BAY 1238097 targeted the NFKB/TLR/JAK/STAT signalling pathways, MYC and E2F1‐regulated genes, cell cycle regulation and chromatin structure. The gene expression profiling signatures also highly overlapped with the signatures obtained with other BET Bromodomain inhibitors and partially overlapped with HDAC‐inhibitors, mTOR inhibitors and demethylating agents. Notably, BAY 1238097 presented in vitro synergism with EZH2, mTOR and BTK inhibitors. In conclusion, the BET inhibitor BAY 1238097 presented promising anti‐lymphoma preclinical activity in vitro and in vivo, mediated by the interference with biological processes driving the lymphoma cells. Our data also indicate the use of combination schemes targeting EZH2, mTOR and BTK alongside BET bromodomains.
Glucocorticoids (GCs) are the most commonly used antiinflammatory and immunosuppressive drugs. Their outstanding therapeutic effects, however, are often accompanied by severe and sometimes ...irreversible side effects. For this reason, one goal of research in the GC field is the development of new drugs, which show a reduced side-effect profile while maintaining the antiinflammatory and immunosuppressive properties of classical GCs. GCs affect gene expression by both transactivation and transrepression mechanisms. The antiinflammatory effects are mediated to a major extent via transrepression, while many side effects are due to transactivation. Our aim has been to identify ligands of the GC receptor (GR), which preferentially induce transrepression with little or no transactivating activity. Here we describe a nonsteroidal selective GR-agonist, ZK 216348, which shows a significant dissociation between transrepression and transactivation both in vitro and in vivo. In a murine model of skin inflammation, ZK 216348 showed antiinflammatory activity comparable to prednisolone for both systemic and topical application. A markedly superior side-effect profile was found with regard to increases in blood glucose, spleen involution, and, to a lesser extent, skin atrophy; however, adrenocorticotropic hormone suppression was similar for both compounds. Based on these findings, ZK 216348 should have a lower risk, e.g., for induction of diabetes mellitus. The selective GR agonists therefore represent a promising previously undescribed class of drug candidates with an improved therapeutic index compared to classical GCs. Moreover, they are useful tool compounds for further investigating the mechanisms of GR-mediated effects.
BackgroundThe second messenger diacylglycerol plays a key role in T-cell receptor (TCR) downstream signaling and T-cell activation. Diacylglycerol kinase zeta (DGKζ) is a lipid kinase that regulates ...T-cell activation by phosphorylating diacylglycerol to produce phosphatidic acid, thereby acting as a ligand-independent, intracellular immune checkpoint. The inhibition of DGKζ offers the potential to enhance T-cell priming against suboptimal tumor antigens and to overcome multiple immunosuppressive mechanisms in the tumor microenvironment in a TCR engagement-dependent manner. We evaluated the specificity, efficacy, and safety of the DGKζ inhibitor BAY 2965501 in various preclinical in vitro and in vivo studies.Methods and ResultsBAY 2965501 is a highly selective, potent human/mouse cross-reactive DGKζ inhibitor. In vitro, BAY 2965501 increased natural killer cell- and T-cell-mediated tumor cell killing and enhanced interleukin 2-induced natural killer cell activation. Importantly, the inhibition of DGKζ by BAY 2965501 was able to overcome inhibitory signals conferred by transforming growth factor beta, prostaglandin E2, and adenosine signaling in T cells. However, BAY 2965501 showed no direct anti-proliferative effects on human tumor cell lines in vitro. Single-cell sequencing of human tumor-infiltrating lymphocytes isolated from primary human tumors revealed high expression of DGKζ specifically in exhausted CD8+ TCR clonotypes, suggesting a potential immunosuppressive role in this T-cell subpopulation. Furthermore, BAY 2965501 effectively enhanced the in vitro anti-tumor reactivity of human T cells expressing tumor-reactive TCRs. In vivo, BAY 2965501 reduced T-cell exhaustion markers, such as programmed cell death receptor 1 and T-cell immunoglobulin mucin 3, and enhanced antiviral T-cell responses in mice chronically infected with lymphocytic choriomeningitis virus. In MB49, F9, and Hepa129 syngeneic mouse tumor models, BAY 2965501 as monotherapy reduced tumor growth when compared with vehicle treatment. Combining BAY 2965501 with an anti-programmed cell death ligand-1 (anti-PDL-1) antibody reduced tumor growth vs anti-PDL-1 monotherapy. Preclinical toxicology studies showed only low-grade gastrointestinal effects, suggesting a tolerable clinical profile.ConclusionsIn summary, BAY 2965501 is a highly potent and selective, orally available DGKζ inhibitor. A first-in-human clinical trial of BAY 2965501 in solid tumors is currently enrolling patients (NCT05614102). This study will evaluate the safety, tolerability, maximum tolerated or administered dose, pharmacokinetics, pharmacodynamics, and tumor response profile of BAY 2965501.AcknowledgementsEditing support was provided by Rachel Fairbanks, BA (Hons), Complete HealthVizion, IPG Health Medical Communications, and was funded by Bayer AG.Ethics ApprovalAll animal experiments were conducted in accordance with the German Animal Welfare Law and approved by Berlin authorities (Landesamt für Arbeitsschutz, Gesundheitsschutz und technische Sicherheit Berlin, LAGetSi; code number A0378/12)
BackgroundThe metabolism of tryptophan to kynurenines (KYN) by indoleamine-2,3-dioxygenase or tryptophan-2,3-dioxygenase is a key pathway of constitutive and adaptive tumor immune resistance. The ...immunosuppressive effects of KYN in the tumor microenvironment are predominantly mediated by the aryl hydrocarbon receptor (AhR), a cytosolic transcription factor that broadly suppresses immune cell function. Inhibition of AhR thus offers an antitumor therapy opportunity via restoration of immune system functions.MethodsThe expression of AhR was evaluated in tissue microarrays of head and neck squamous cell carcinoma (HNSCC), non-small cell lung cancer (NSCLC) and colorectal cancer (CRC). A structure class of inhibitors that block AhR activation by exogenous and endogenous ligands was identified, and further optimized, using a cellular screening cascade. The antagonistic properties of the selected AhR inhibitor candidate BAY 2416964 were determined using transactivation assays. Nuclear translocation, target engagement and the effect of BAY 2416964 on agonist-induced AhR activation were assessed in human and mouse cancer cells. The immunostimulatory properties on gene and cytokine expression were examined in human immune cell subsets. The in vivo efficacy of BAY 2416964 was tested in the syngeneic ovalbumin-expressing B16F10 melanoma model in mice. Coculture of human H1299 NSCLC cells, primary peripheral blood mononuclear cells and fibroblasts mimicking the human stromal-tumor microenvironment was used to assess the effects of AhR inhibition on human immune cells. Furthermore, tumor spheroids cocultured with tumor antigen-specific MART-1 T cells were used to study the antigen-specific cytotoxic T cell responses. The data were analyzed statistically using linear models.ResultsAhR expression was observed in tumor cells and tumor-infiltrating immune cells in HNSCC, NSCLC and CRC. BAY 2416964 potently and selectively inhibited AhR activation induced by either exogenous or endogenous AhR ligands. In vitro, BAY 2416964 restored immune cell function in human and mouse cells, and furthermore enhanced antigen-specific cytotoxic T cell responses and killing of tumor spheroids. In vivo, oral application with BAY 2416964 was well tolerated, induced a proinflammatory tumor microenvironment, and demonstrated antitumor efficacy in a syngeneic cancer model in mice.ConclusionsThese findings identify AhR inhibition as a novel therapeutic approach to overcome immune resistance in various types of cancers.
Palladium complexes with chiral phosphinooxazoline ligands are efficient catalysts for enantioselective Heck reactions with aryl or alkenyl triflates and cyclic olefins. In the arylation and ...alkenylation of 1,2-dihydrofuran, cyclopentene, 2,3-dihydro-4
H-pyran, 4,7-dihydro-1,3-dioxepin, and
N-methoxycarbonyl-2,3-dihydropyrrole high yields and good to excellent enantioselectivities have been obtained. In contrast to palladium-BINAP catalysts, the catalysts derived from phosphinooxazolines show a very low tendency to promote isomerization of the product by C–C double bond migration.
Bromodomain protein 4 (BRD4) is a member of the bromodomain and extra-terminal domain (BET) protein family. It binds to acetylated histone tails via its tandem bromodomains BD1 and BD2 and forms a ...complex with the positive transcription elongation factor b, which controls phosphorylation of RNA polymerase II, ultimately leading to stimulation of transcription elongation. An essential role of BRD4 in cell proliferation and cancer growth has been reported in several recent studies. We analyzed the binding of BRD4 BD1 and BD2 to different partners and showed that the strongest interactions took place with di- and tetra-acetylated peptides derived from the histone 4 N-terminal tail. We also found that several histone 4 residues neighboring the acetylated lysines significantly influenced binding. We generated 10 different BRD4 BD1 mutants and analyzed their affinities to acetylated histone tails and to the BET inhibitor JQ1 using several complementary biochemical and biophysical methods. The impact of these mutations was confirmed in a cellular environment. Altogether, the results show that Trp-81, Tyr-97, Asn-140, and Met-149 play similarly important roles in the recognition of acetylated histones and JQ1. Pro-82, Leu-94, Asp-145, and Ile-146 have a more differentiated role, suggesting that different kinds of interactions take place and that resistance mutations compatible with BRD4 function are possible. Our study extends the knowledge on the contribution of individual BRD4 amino acids to histone and JQ1 binding and may help in the design of new BET antagonists with improved pharmacological properties.
Background: BRD4 is a reader of acetylated histones.
Results: Mutational analysis of BRD4 BD1 allowed the identification of three groups with different binding profiles.
Conclusion: Pro-82, Leu-94, Asp-145, and Ile-146 have a differentiated role in acetyl-lysine and inhibitor interaction.
Significance: Identification of residues essential for BRD4 function will guide the design of novel inhibitors.
USP21 belongs to the ubiquitin-specific protease (USP) subfamily of deubiquitinating enzymes (DUBs). Due to its relevance in tumor development and growth, USP21 has been reported as a promising novel ...therapeutic target for cancer treatment. Herein, we present the discovery of the first highly potent and selective USP21 inhibitor. Following high-throughput screening and subsequent structure-based optimization, we identified BAY-805 to be a non-covalent inhibitor with low nanomolar affinity for USP21 and high selectivity over other DUB targets as well as kinases, proteases, and other common off-targets. Furthermore, surface plasmon resonance (SPR) and cellular thermal shift assays (CETSA) demonstrated high-affinity target engagement of BAY-805, resulting in strong NF-κB activation in a cell-based reporter assay. To the best of our knowledge, BAY-805 is the first potent and selective USP21 inhibitor and represents a valuable high-quality in vitro chemical probe to further explore the complex biology of USP21.
The growth of uterine fibroids is sex hormone-dependent and commonly associated with highly incapacitating symptoms. Most treatment options consist of the control of these hormonal effects, ...ultimately blocking proliferative estrogen signaling (i.e., oral contraceptives/antagonization of human gonadotropin-releasing hormone receptor hGnRH-R activity). Full hGnRH-R blockade, however, results in menopausal symptoms and affects bone mineralization, thus limiting treatment duration or demanding estrogen add-back approaches. To overcome such issues, we aimed to identify novel, small-molecule hGnRH-R antagonists. This led to the discovery of compound BAY 1214784, an orally available, potent, and selective hGnRH-R antagonist. Altering the geminal dimethylindoline core of the initial hit compound to a spiroindoline system significantly improved GnRH-R antagonist potencies across several species, mandatory for a successful compound optimization in vivo. In a first-in-human study in postmenopausal women, once daily treatment with BAY 1214784 effectively lowered plasma luteinizing hormone levels by up to 49%, at the same time being associated with low pharmacokinetic variability and good tolerability.
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We report on the discovery of two new lead series for the development of glucocorticoid receptor agonists. Firstly, the discovery of tetrahydronaphthalenes led to metabolically stable ...and dissociated compounds. Their binding mode to the glucocorticoid receptor could be elucidated through an X-ray structure. Closer inspection into the reaction path and analyses of side products revealed a new amino alcohol series also addressing the glucocorticoid receptor and demonstrating strong anti-inflammatory activity in vitro.
Progesterone receptor agonists are used in female contraception, hormone replacement therapy or some gynecological conditions like endometriosis. The interest for antagonists or selective ...progesterone receptor modulators (SPRMs) is growing. Recent reports on this class of compounds indicate that they could become the next generation of therapeutics in gynecological treatments.
This overview summarizes the work on progesterone receptor agonists, SPRMs and antagonists reported in the patent literature in the past 4 years.
The focus of the article is the examination of patents, primarily published as WO, EU or US patents since 2005. In some cases, additional data from the public literature is included into the discussion. These data are of substantial interest as the available biological data disclosed in patents are usually limited for new compound classes.
Some highly active clusters of compounds have been disclosed in the past 4 years. The current research seems to focus on SPRMs and progesterone receptor antagonists.
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