Selective Glucocorticoid Receptor Modulators Research Articles

Discovery and MD simulation of a Triterpenoid Zj7 as GR Modulator Targeting Non‐Classical GRE with Potent Anti‐Obesity Activity

Despite the potential of non‐classical glucocorticoid response element (GRE)‐selective glucocorticoid receptor (GR) modulators in biomedical sciences, progress has not yet been made. In this study, we discovered a first‐in‐class chemical modulator that selectively suppresses the transcriptional activity of the GR in a gene with a non‐classical GRE, but not with classical GREs. The orexigenic agouti‐related peptide (Agrp)‐gene with a non‐classical GRE was chosen for this study. Similarity‐implemented virtual screening and rational modification of the structure of the initial hit compounds led to the identification of a pentacyclic natural triterpenoid, Zj7 (2‐O‐trans‐p‐coumaroylalphitolic acid). With this compound, we recently reported the verification of the orexigenic function and mechanism of action of GR in AgRP neurons. Herein, we describe the detailed discovery process leading to the identification of Zj7 and propose its molecular mode of action using molecular dynamics simulation.

Final overall survival data from a randomized, open-label, phase II study of relacorilant, a selective glucocorticoid receptor modulator, in combination with nab-paclitaxel among patients with recurrent platinum-resistant ovarian cancer

Final overall survival data from a randomized, open-label, phase II study of relacorilant, a selective glucocorticoid receptor modulator, in combination with nab-paclitaxel among patients with recurrent platinum-resistant ovarian cancer

Glucocorticoids induce HMGB1 release in primary cultured rat cortical microglia

Stress, a risk factor for major depressive disorder and Alzheimer disease, leads to the release of high-mobility group box-1 (HMGB1) protein, which in turn causes neuroinflammation. The mechanism underlying stress-induced HMGB1 release is unknown, but stress-associated glucocorticoids could be involved. Primary cultured rat cortical microglia and neurons were treated with corticosterone, a stress-associated glucocorticoid, and HMGB1 release was measured by ELISA and western blotting to test this hypothesis. With corticosterone treatment, significant HMGB1 was released in microglia but not in neuronal cell cultures. HMGB1 mRNA expression and HMGB1 protein expression in microglia were not affected by corticosterone treatment. Thus, the source of extracellular HMGB1 released into the medium is likely to be existing nuclear HMGB1 rather than newly synthesized HMGB1. Corticosterone-induced HMGB1 release in microglia culture was significantly attenuated by blocking glucocorticoid receptors but not mineralocorticoid receptors. Dexamethasone, a selective glucocorticoid receptor agonist, and dexamethasone-bovine serum albumin (BSA), a membrane-impermeable glucocorticoid receptor agonist used to confirm the membrane receptor-mediated effects of glucocorticoids, increased the release of HMGB1. Immunocytochemistry showed that HMGB1 translocated from the nucleus to the cytoplasm following dexamethasone or dexamethasone-BSA treatment through glucocorticoid receptors. The present findings suggest that glucocorticoids stimulate microglial membrane glucocorticoid receptors and trigger cytoplasmic translocation and extracellular release of nuclear HMGB1. Thus, under stress conditions, glucocorticoids induce microglial HMGB1 release, leading to a neuroinflammatory state that could mediate neurological disorders.

Molecular mechanisms of novel selective glucocorticoid receptor agonist action in breast cancer cells

Introduction. Glucocorticoids (GC) are widely used in breast cancer (BC) therapy to reduce the side effects of cytostatic drugs and may exhibit antiproliferative effects on luminal BC cells. The biological action of GC is mediated by glucocorticoid receptor (GR) by two mechanisms: transrepression, which determines the therapeutic effect of GC, and transactivation (associated with the development of side effects, resistance to cytotoxic drugs, cancer progression and metastasis). Selective GR agonists (SEGRA) which may selective activate transrepression are a promising alternative to GC to use in combination cancer therapy. One of the most studied SEGRA is Compound A (CpdA). The instability of CpdA limits its use in clinical practice. So recently we performed synthesis and evaluation of biological activities of the CpdA analogue, CpdA-03.Aim. To compare the effects of SEGRA CpdA-03 and CpdA and dexamethasone on proliferative activity of breast cancer cells, as well as receptor nuclear translocation and activation of GR-dependent genes in breast cancer cells.Materials and methods. Luminal (MCF-7) and triple negative (MDA-MB-231) BC cell lines were used. The effect of CpdA-03 on proliferation was evaluated by direct counting of viable cells with trypan blue staining. The effect of the compound on cell distribution by cell cycle phases was assessed by flow cytofluorimetry with propidium iodide staining. Changes in the expression of GR-dependent genes after incubation with CpdA-03 were evaluated by quantitative polymerase chain reaction. Additionally, the ability of the new SEGRA to induce transactivation-associated translocation of the receptor to the nucleus was evaluated by Western blotting.Results. CpdA-03 was shown to suppress proliferation of luminal and triple negative BC cells. This compound causes changes in the expression of a number of GC-inducible genes, but does not stimulate GR phosphorylation and translocation to the nucleus in BC cells.Conclusion. The observed suppression of cell proliferation, as well as the ability of CpdA-03 to reduce gene expression of proteins regulating intercellular adhesion and cell migration, intracellular signaling, stress response, and transcription in BC cells makes it relevant for further development of the drug for use in the combination therapy of cancers including breast cancer.

7005 Characterization of Clinical Candidate Miricorilant in Preclinical Models for NASH

Abstract Disclosure: T.J. Moll: None. E.M. Viho: None. M. Gentenaar: None. H. Hunt: Employee; Self; Corcept Therapeutics. O.C. Meijer: Grant Recipient; Self; Corcept Therapeutics. J. Kroon: Research Investigator; Self; Corcept Therapeutics. Background and aim: Miricorilant (CORT118335) is a selective glucocorticoid receptor (GR) modulator that is under clinical development for the treatment of non-alcohol steatohepatitis (NASH). It was previously shown that miricorilant treatment effectively lowers hepatic lipid content in mouse models of NASH. The aim of this study is to further characterize the effects of miricorilant in the mouse liver and in human liver tissue. Methods: In mouse liver tissue, we investigated the agonistic and antagonistic properties of miricorilant on GR activity. Eight-week-old male C57BL/6J mice were fed with a control diet or miricorilant-supplemented diet (resulting in an estimated dose of 60 mg/kg/day) for 6 days and 1.5 mg/kg corticosterone was injected to monitor the effects of miricorilant on GR-responsive gene expression. We next accessed the time-dependency of the lipid-lowering effects of miricorilant in the mouse liver. Mice were fed with a high-fat, high-fructose diet (HFHFD) for 3 weeks before treatment with 60 mg/kg/day miricorilant for one, three or six days by oral gavage, and triglyceride content in the liver was measured at endpoint. In human liver tissue, we investigated the effects of miricorilant on precision-cut liver slices (PCLS) obtained from two independent donors with pre-existing steatosis. PCLS were cultured for a total of 168 hours in the presence of 100 nM hydrocortisone, and with or without an exogenous lipid challenge. PCLS were treated with 200-600 nM miricorilant for 96 hours before triglyceride content was measured. RNA-sequencing was performed on PCLS after 24 hours of 200-400 nM miricorilant exposure. Results: In the mouse liver, miricorilant exhibited a unique combination of agonistic and antagonistic properties on GR-responsive gene expression. Miricorilant effectively lowered HFHFD-induced lipid accumulation in the mouse liver as soon as three days after treatment. In human PCLS, miricorilant treatment lowered triglyceride content in both donors. RNA-sequencing revealed respectively 40 and 128 differentially expressed genes after 200 and 400 nM miricorilant treatment. Pathway analysis revealed very-low-density lipoprotein (VLDL) particle remodeling as a significant enriched pathway, providing a possible explanation for the lowered triglyceride content upon miricorilant treatment. Conclusion: Miricorilant rapidly and effectively lowers hepatic lipid content in the mouse liver and in human PCLS, possibly via modulation of VLDL remodeling. Presentation: 6/2/2024

Protopanaxadiol synergizes with glucocorticoids to enhance the therapeutic effect in adriamycin-induced nephrotic syndrome

To date, glucocorticoids remain the mainstay of treatment of nephrotic syndrome (NS). However, serious side effects and development of drug-resistance following long-term use limit the application of glucocorticoids. Protopanaxadiol (PPD) possesses activity of dissociating transactivation from transrepression by glucocorticoid receptor (GR), which may serve as a potential selective GR modulator. However, steroid-like effects of PPD in vivo are unclear and not defined. How to translate PPD into clinical practice remains to be explored. The current study explored the renoprotection and potential mechanism of PPD and its combination with steroid hormones using adriamycin-induced NS rats. Adriamycin was given intravenously to rats to induce nephropathy. The determination of proteinuria, biochemical changes and inflammatory cytokines were performed, and pathological changes were examined by histopathological examination. Immunostaining and PCR were used to analyze the expression of interesting proteins and genes. The results showed that PPD, alone and in combination with prednisone, efficiently alleviate the symptoms of NS, attenuate nephropathy, improve adriamycin-induced podocyte injury by reducing desmin and increasing synaptopodin expression. In addition, the combined treatment reduced the expression of NF-κB protein and mRNA, as well as cytokine levels, and yet increased the expression of GR protein and mRNA. PPD modulated the transactivation of GR, manifested as repressing TAT, PEPCK and ANGPTL4 mRNA expressions mediated by GR. Meanwhile, PPD inhibited elevation of blood glucose and immune organ atrophy induced by prednisone. In summary, PPD increases the therapeutic effect of prednisone in NS while effectively prevents or decreases the appearance of side effects of glucocorticoids.

Relacorilant plus nab-paclitaxel for the treatment of metastatic pancreatic ductal adenocarcinoma: results from the open-label RELIANT study.

Modulation of glucocorticoid receptor (GR) activity in tumor cells enhances chemotherapy efficacy. We evaluated the selective GR modulator relacorilant plus nab-paclitaxel in patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) who had received at least 2 prior therapy lines. In this open-label, single-arm, phase III study, patients received once-daily oral relacorilant (100mg, titrated to 150mg in 25mg increments/cycle) and nab-paclitaxel (80mg/m2) on days 1, 8, and 15 of 28-day cycles. The primary efficacy endpoint was objective response rate (ORR) by blinded independent central review. Progression-free survival (PFS), overall survival (OS), target gene modulation, and safety were also assessed. Of 43 patients enrolled, 31 were evaluable for ORR (12 did not reach first postbaseline radiographic assessment). An interim analysis to assess whether ORR was ≥10% showed no confirmed responses and the study was discontinued. Two (6.5%) patients attained unconfirmed partial responses and 15 (48.4%) had stable disease. Fourteen of 31 (45.2%) patients had reductions in target lesion size, despite prior nab-paclitaxel exposure in 12 of the 14. Median PFS and OS were 2.4 months (95% CI, 1.4-4.2) and 3.9 months (95% CI, 2.8-4.9), respectively. The most common adverse events were fatigue and nausea. RNA analysis confirmed that relacorilant plus nab-paclitaxel suppressed 8 cortisol target genes of interest. Relacorilant plus nab-paclitaxel showed modest antitumor activity in heavily pretreated patients with mPDAC, with no new safety signals. Studies of this combination in other indications with a high unmet medical need are ongoing.

Protopanaxadiol derivative: A plant origin of novel selective glucocorticoid receptor modulator with anti-inflammatory effect

Constant efforts have been made to move towards maintaining the positive anti-inflammatory functions of glucocorticoids (GCs) while minimizing side effects. The anti-inflammatory effect of GCs is mainly attributed to the inhibition of major inflammatory pathways such as NF-κB through GR transrepression, while its side effects are mainly mediated by transactivation. Here, we investigated the selective glucocorticoid receptor modulator (SGRM)-like properties of a plant-derived compound. In this study, glucocorticoid receptor (GR)-mediated alleviation of inflammation by SP-8 was investigated by a combination of in vitro, in silico, and in vivo approaches. Molecular docking and cellular thermal shift assay suggested that SP-8 bound stably to the active site of GR via hydrogen bonding and hydrophobic interactions. SP-8 activated GR, induced GR nuclear translocation, and inhibited NF-κB pathway activation. Furthermore, SP-8 did not up-regulate the gene and protein expression of PEPCK and TAT in HepG2 cells, and it did not induce fat deposition like GC and has little effect on bone metabolism. Interestingly, SP-8 upregulated GR protein expression and did not cause GR phosphorylation at Ser211 in RAW264.7 cells. This work proved that SP-8 dissociated characteristics of transrepression and transactivation can be separated. In addition, the in vitro and in vivo anti-inflammatory effects of SP-8 were confirmed in LPS-induced RAW 264.7 cells and in a mouse model of DSS-induced ulcerative colitis, respectively. In conclusion, SP-8 might serve as a potential SGRM and might hold great potential for therapeutic use in inflammatory diseases.

Synthesis and Anti-Cancer Activity of the Novel Selective Glucocorticoid Receptor Agonists of the Phenylethanolamine Series.

Glucocorticoids (GCs) are widely used for treating hematological malignancies despite their multiple adverse effects. The biological response to GCs relies on glucocorticoid receptor (GR) transrepression (TR) that mediates the anticancer effects and transactivation (TA) associated with the side effects. Selective GR agonists (SEGRAs) preferentially activating GR TR could offer greater benefits in cancer treatment. One of the well-characterized SEGRAs, 2-(4-acetoxyphenyl)-2-chloro-N-methylethylammonium-chloride (CpdA), exhibited anticancer activity; however, its translational potential is limited due to chemical instability. To overcome this limitation, we obtained CpdA derivatives, CpdA-01-CpdA-08, employing two synthetic strategies and studied their anti-tumor activity: 4-(1-hydroxy-2-(piperidin-1-yl)ethyl)phenol or CpdA-03 demonstrated superior GR affinity and stability compared to CpdA. In lymphoma Granta and leukemia CEM cell lines, CpdA-03 ligand exhibited typical SEGRA properties, inducing GR TR without triggering GR TA. CpdA-03 effects on cell viability, growth, and apoptosis were similar to the reference GR ligand, dexamethasone (Dex), and the source compound CpdA. In vivo testing of CpdA-03 activity against lymphoma on the transplantable P388 murine lymphoma model showed that CpdA-03 reduced tumor volume threefold, outperforming Dex and CpdA. In conclusion, in this work, we introduce a novel SEGRA CpdA-03 as a promising agent for lymphoma treatment with fewer side effects.

The effect of AZD9567 vs. prednisolone on glycaemic control in patients with type 2 diabetes mellitus: Results from a phase 2a clinical trial.

Corticosteroids are the treatment of choice for many inflammatory diseases but often lead to adverse effects, including hyperglycaemia. This study investigated the mechanisms driving differential effects on glucose control for AZD9567, an oral nonsteroidal selective glucocorticoid receptor modulator vs. prednisolone in 46 patients with type 2 diabetes mellitus. In this randomized, double-blind, 2-way cross-over study (NCT04556760), participants received either AZD9567 72 mg and prednisolone 40 mg daily (cohort 1); AZD9567 40 mg and prednisolone 20 mg daily (cohort 2); or placebo and prednisolone 5mg daily (cohort 3). Treatment duration was 3days with a 3-week washout between treatment periods. Glycaemic control was assessed after a standardized meal and with continuous glucose monitoring. A significant difference between AZD9567 and prednisolone in favour of AZD9567 was observed for the change from baseline to Day 4 glucose excursions postmeal in cohort 1 (glucose area under the curve from 0 to 4h -4.54%; 95% confidence interval [CI]: -8.88, -0.01; P = .049), but not in cohort 2 (-5.77%; 95% CI: -20.92, 12.29; P = .435). In cohort 1, significant differences between AZD9567 and prednisolone were also seen for the change from baseline to day 4 in insulin and glucagon secretion postmeal (P < .001 and P = .005, respectively) and change from baseline to Day 4 in GLP-1 response (P = .022). Significant differences between AZD9567 and prednisolone for 24-h glucose control were observed for both cohort 1 (-1.507 mmol/L; 95% CI: -2.0820, -0.9314; P < .001) and cohort 2 (-1.110 mmol/L; 95% CI -1.7257, -0.4941; P < .001). AZD9567 significantly reduced treatment-induced hyperglycaemia compared with prednisolone.

Vamorolone: revolutionizing Duchenne muscular dystrophy treatment

Duchenne muscular dystrophy (DMD) is a severe inherited neuromuscular disorder characterized by a dystrophin gene mutation, leading to progressive muscle weakness and structural degradation. Current management strategies focus on multidisciplinary approaches to mitigate symptoms and enhance quality of life. Conventional glucocorticoids present challenges due to their complex nature and severe side effects. Vamorolone, a first-in-class dissociative steroidal drug recently Food and Drug Administration (FDA) - approved, distinguishes itself through enduring anti-inflammatory effects with reduced safety concerns. Pharmacologically, Vamorolone's mechanism of action, differentiating it from traditional corticosteroids, involves selective glucocorticoid receptor (GR) modulation and mineralocorticoid receptor (MR) antagonism, offering improved safety and tolerability. Notably, its unique Δ9,11 modification prevents adverse receptor interactions, demonstrating superior safety in inhibiting inflammation across various cell types. This article explores Vamorolone's pharmacokinetics, drug interactions, and adverse effects, underscoring its well-tolerated profile with reversible hypothalamic-pituitary-adrenal axis suppression as a notable concern. Comparative studies against prednisone reveal Vamorolone's efficacy in improving muscle strength with minimal side effects, validated through the pivotal Phase IIb VISION-DMD study. Ultimately, Vamorolone has attained a breakthrough status in DMD treatment. Its endorsement by the FDA underscores Vamorolone as a transformative linchpin, heralding a new era in revolutionizing DMD care.

Characterization of a new selective glucocorticoid receptor modulator with anorexigenic activity

Obesity, a worldwide epidemic, leads to various metabolic disorders threatening human health. In response to stress or fasting, glucocorticoid (GC) levels are elevated to promote food intake. This involves GC-induced expression of the orexigenic neuropeptides in agouti-related protein (AgRP) neurons of the hypothalamic arcuate nucleus (ARC) via the GC receptor (GR). Here, we report a selective GR modulator (SGRM) that suppresses GR-induced transcription of genes with non-classical glucocorticoid response elements (GREs) such as Agrp-GRE, but not with classical GREs, and via this way may serve as a novel anti-obesity agent. We have identified a novel SGRM, 2-O-trans-p-coumaroylalphitolic acid (Zj7), a triterpenoid extracted from the Ziziphus jujube plant, that selectively suppresses GR transcriptional activity in Agrp-GRE without affecting classical GREs. Zj7 reduces the expression of orexigenic genes in the ARC and exerts a significant anorexigenic effect with weight loss in both high fat diet-induced obese and genetically obese db/db mouse models. Transcriptome analysis showed that Zj7 represses the expression of a group of orexigenic genes including Agrp and Npy induced by the synthetic GR ligand dexamethasone (Dex) in the hypothalamus. Taken together, Zj7, as a selective GR modulator, showed beneficial metabolic activities, in part by suppressing GR activity in non-classical GREs in orexigenic genes. This study demonstrates that a potential anorexigenic molecule may allow GRE-specific inhibition of GR transcriptional activity, which is a promising approach for the treatment of metabolic disorders.

A Phase I Trial of Enzalutamide Plus Selective Glucocorticoid Receptor Modulator Relacorilant in Patients with Metastatic Castration-Resistant Prostate Cancer.

The majority of patients with metastatic prostate cancer who receive androgen-deprivation therapy and androgen receptor (AR) signaling inhibitors (ARSI) progress. Activation of the glucocorticoid receptor (GR) is associated with ARSI resistance. This single-arm phase I trial assessed safety and pharmacokinetic (PK) feasibility of a combined AR antagonist (enzalutamide) and selective GR modulator (relacorilant) in patients with metastatic castration-resistant prostate cancer (mCRPC). This was a phase I trial (NCT03674814) of relacorilant and enzalutamide in patients with refractory mCRPC enrolled using a 6+3 design. The enzalutamide dose was kept constant at 120 mg/d with escalating doses of relacorilant based on safety and PK measures in cohorts of ≥6 patients. The primary objective was safety and establishment of pharmacologically active doses. Secondary objectives were related to antitumor activity. Thirty-five patients with mCRPC were enrolled. Twenty-three were accrued across three dose cohorts in the dose-escalation phase, and 12 enrolled at the recommended phase II dose. The combination was generally well tolerated, safe, and achieved desirable enzalutamide PK. RP2D of 120 + 150 mg/d, respectively, was established. Median time on study was 2.2 months with four patients remaining on study for longer than 11 months. Four of 12 evaluable patients had a prostate-specific antigen (PSA) partial response. This is the first prospective trial combining an AR antagonist and a nonsteroidal selective GR modulator. The combination was safe and well tolerated with PSA response and prolonged disease control observed in a limited subset of patients. Further prospective trials are justified to evaluate efficacy and identify predictive biomarkers of response.

Selective Modulation of the Human Glucocorticoid Receptor Compromises GR Chromatin Occupancy and Recruitment of p300/CBP and the Mediator Complex

Exogenous glucocorticoids are frequently used to treat inflammatory disorders and as adjuncts for the treatment of solid cancers. However, their use is associated with severe side effects and therapy resistance. Novel glucocorticoid receptor (GR) ligands with a patient-validated reduced side effect profile have not yet reached the clinic. GR is a member of the nuclear receptor family of transcription factors and heavily relies on interactions with coregulator proteins for its transcriptional activity. To elucidate the role of the GR interactome in the differential transcriptional activity of GR following treatment with the selective GR agonist and modulator dagrocorat compared to classic (ant)agonists, we generated comprehensive interactome maps by high-confidence proximity proteomics in lung epithelial carcinoma cells. We found that dagrocorat and the antagonist RU486 both reduced GR interaction with CREB-binding protein/p300 and the mediator complex compared to the full GR agonist dexamethasone. Chromatin immunoprecipitation assays revealed that these changes in GR interactome were accompanied by reduced GR chromatin occupancy with dagrocorat and RU486. Our data offer new insights into the role of differential coregulator recruitment in shaping ligand-specific GR-mediated transcriptional responses.

Synephrine and Its Derivative Compound A: Common and Specific Biological Effects.

This review is focused on synephrine, the principal phytochemical found in bitter orange and other medicinal plants and widely used as a dietary supplement for weight loss/body fat reduction. We examine different aspects of synephrine biology, delving into its established and potential molecular targets, as well as its mechanisms of action. We present an overview of the origin, chemical composition, receptors, and pharmacological properties of synephrine, including its anti-inflammatory and anti-cancer activity in various in vitro and animal models. Additionally, we conduct a comparative analysis of the molecular targets and effects of synephrine with those of its metabolite, selective glucocorticoid receptor agonist (SEGRA) Compound A (CpdA), which shares a similar chemical structure with synephrine. SEGRAs, including CpdA, have been extensively studied as glucocorticoid receptor activators that have a better benefit/risk profile than glucocorticoids due to their reduced adverse effects. We discuss the potential of synephrine usage as a template for the synthesis of new generation of non-steroidal SEGRAs. The review also provides insights into the safe pharmacological profile of synephrine.

Glucocorticoid Receptor (GR) Activation Is Associated with Increased cAMP/PKA Signaling in Castration-Resistant Prostate Cancer.

In castration-resistant prostate cancer (CRPC), increased glucocorticoid receptor (GR) expression and ensuing transcriptional activity have been proposed as an oncogenic "bypass" mechanism in response to androgen receptor (AR) signaling inhibition (ARSi). Here, we report that GR transcriptional activity acquired following ARSi is associated with the upregulation of cyclic adenosine monophosphate (cAMP)-associated gene expression pathways in both model systems and metastatic prostate cancer patient samples. In the context of ARSi, the expression of GR-mediated genes encoding cAMP signaling pathway-associated proteins can be inhibited by treatment with selective GR modulators (SGRMs). For example, in the context of ARSi, we found that GR activation resulted in upregulation of protein kinase inhibitor beta (PKIB) mRNA and protein levels, leading to nuclear accumulation of the cAMP-dependent protein kinase A catalytic subunit (PKA-c). Increased PKA-c, in turn, is associated with increased cAMP response element-binding protein phosphorylation and activity. Furthermore, enzalutamide and SGRM combination therapy in mice bearing CRPC xenografts delayed CRPC progression compared with enzalutamide therapy alone, and reduced tumor PKIB mRNA expression. Supporting the clinical importance of GR/PKA signaling activation in CRPC, we found a significant enrichment of both cAMP pathway signaling-associated gene expression and high NR3C1 (GR) activity in patient-derived xenograft models and metastatic human CRPC samples. These findings suggest a novel mechanism linking CRPC-induced GR transcriptional activity with increased cAMP signaling in AR-antagonized CRPC. Furthermore, our findings suggest that GR-specific modulation in addition to AR antagonism may delay GR+ CRPC time to recurrence, at least in part, by inhibiting tumor cAMP/PKA pathways.

Relacorilant, a Selective Glucocorticoid Receptor Modulator in Development for the Treatment of Patients With Cushing Syndrome, Does Not Cause Prolongation of the Cardiac QT Interval

ObjectiveTo assess the effect of relacorilant, a selective glucocorticoid receptor modulator under investigation for the treatment of patients with endogenous hypercortisolism (Cushing syndrome [CS]), on the heart rate–corrected QT interval (QTc). MethodsThree clinical studies of relacorilant were included: (1) a first-in-human, randomized, placebo-controlled, ascending-dose (up to 500 mg of relacorilant) study in healthy volunteers; (2) a phase 1 placebo- and positive-controlled thorough QTc (TQT) study of 400 and 800 mg of relacorilant in healthy volunteers; and (3) a phase 2, open-label study of up to 400 mg of relacorilant administered daily for up to 16 weeks in patients with CS. Electrocardiogram recordings were taken, and QTc change from baseline (ΔQTc) was calculated. The association of plasma relacorilant concentration with the effect on QTc in healthy volunteers was assessed using linear mixed-effects modeling. ResultsAcross all studies, no notable changes in the electrocardiogram parameters were observed. At all time points and with all doses of relacorilant, including supratherapeutic doses, ΔQTc was small, generally negative, and, in the placebo-controlled studies, similar to placebo. In the TQT study, placebo-corrected ΔQTc with relacorilant was small and negative, whereas placebo-corrected ΔQTc with moxifloxacin positive control showed rapid QTc prolongation. These results constituted a negative TQT study. The model-estimated slopes of the concentration-QTc relationship were slightly negative, excluding an association of relacorilant with prolonged QTc. ConclusionAt all doses studied, relacorilant consistently demonstrated a lack of QTc prolongation in healthy volunteers and patients with CS, including in the TQT study. Ongoing phase 3 studies will help further establish the overall benefit-risk profile of relacorilant.

THU475 Ovarian Tumor-cell Glucocorticoid Receptor Activity Modulates Cytokine Secretion Promoting Recruitment And Activation of Immunosuppressive Cells Into The Tumor Microenvironment

Abstract Disclosure: M. Taya: None. E. LeBlanc: None. L. Bennett: None. S.D. Conzen: None. Elevated levels of immunosuppressive myeloid-derived suppressor cells (MDSCs) circulate in the peripheral blood or infiltrate both tumors and ascites in ovarian cancer patients, however the cause for this observed phenotype is unknown. MDSCs contribute to tumor immune tolerance primarily via inhibition of cytotoxic T-cells or by activation of immunosuppressive T-regulatory cells. We previously showed that high tumor cell glucocorticoid receptor (GR) expression is associated with a relatively poor prognosis in ovarian cancer patients. Additionally, using primary tumor data retrieved from the ovarian cancer TCGA dataset, we show high tumor GR expression is associated with significantly higher expression of Foxp3, a marker of immunosuppressive T-regulatory cells, as well as CD33, a marker of immunosuppressive myeloid cells, further suggesting an immunosuppressive phenotype in ovarian cancer patients. We thus hypothesize that tumor-intrinsic GR activation in ovarian cancer is associated with increased MDSC infiltration into the tumor microenvironment partly due to the modulation of tumor cell cytokine secretion. To determine whether tumor-cell GR activation modulates the cytokine secretome, we previously showed that GR activation in ovarian cancer cells upregulates secretion of immunomodulatory factors including G-CSF, TGFb and CXCL5. Moreover, co-treatment of cells with a selective GR modulator (SGRM) reverses this effect. Preliminary gene expression data indicate GR mediated cytokine secretion and signaling may involve post-transcriptional or post-translational mechanisms. Considering that elevated levels of these cytokines are necessary for the production and recruitment of MDSCs, these data highlight the relevance of this evident glucocorticoid receptor-cytokine circuit in ovarian cancer cells. Furthermore, we show that this tumor-cell cytokine secretome has the capacity to promote differentiation of MDSCs from precursor myeloid cells in healthy PBMCs. Importantly, measuring expression of activation markers such as Arginase-1 and NOS2 illustrated that these MDSCs are in their functional state. To our knowledge, this is the first evidence that a nuclear receptor in ovarian cancer tumor cells is actively driving MDSC differentiation. Finally, employing ovarian cancer xenograft models as well as a syngeneic ID8 tumor model, treatment with SGRMs demonstrated reduced levels of circulating MDSCs in the peripheral blood as well as tumor infiltrated MDSCs. Using neutralizing antibodies for cytokines, we will now identify key mechanisms, specifically, which targetable immunomodulatory factors are contributing to immune suppression. Based on the insight provided by these data, we propose to determine whether targeting ovarian tumor cell-intrinsic GR activation and resulting MDSC infiltration contributes to improved anti-tumor immune response. Presentation: Thursday, June 15, 2023

THU035 Impact Of Surgery Or Medical Treatment With The Selective Glucocorticoid Receptor Modulator Relacorilant On Hypercoagulopathy In Patients With Cushing Syndrome

Abstract Disclosure: C. Simeoli: None. N. Di Paola: None. A. Stigliano: None. P. Lardo: None. T. Kearney: Other; Self; Corcept Therapeutics. E. Mezosi: Grant Recipient; Self; Corcept Therapeutics. E. Ghigo: None. R. Giordano: None. C.N. Mariash: Grant Recipient; Self; Corcept Therapeutics. D. Donegan: Advisory Board Member; Self; Corcept Therapeutics. Other; Self; Corcept Therapeutics. R.A. Feelders: Consulting Fee; Self; Recordati. Grant Recipient; Self; Corcept Therapeutics. Speaker; Self; Recordati, HRA Pharma. A.L. Hand: Employee; Self; Corcept Therapeutics. A.G. Moraitis: Employee; Self; Corcept Therapeutics. R. Pivonello: Consulting Fee; Self; Corcept Therapeutics. Grant Recipient; Self; Corcept Therapeutics. In patients with Cushing syndrome (CS), hypercoagulability represents a significant concern, leading to an elevated risk for thrombotic events. Hypercoagulability persists for several months (mos) after curative surgery, and current CS treatment guidelines recommend anticoagulation therapy for up to 3 mos after surgery. In patients with Cushing disease, hemostatic parameters may even worsen after surgery, independent of surgical outcome, with improvements beginning about 3 mos after successful surgery (Casonato et al. Blood Coagul Fibrinolysis 1999). This transient worsening may be due to increased inflammation as cortisol levels, and hence cortisol’s anti-inflammatory effects, are reduced after successful surgery, leading to increased activity in the coagulation cascade, which normalizes over time. Here, we evaluate the impact of surgery or treatment with the selective glucocorticoid receptor modulator relacorilant (RELA) on the coagulation state in patients with CS, reporting findings from a retrospective, longitudinal, monocentric, surgical cohort study and an open-label phase 2 study of RELA (NCT02804750). In the surgical study, coagulation markers were assessed in 30 patients before curative surgery and in remission. In the RELA study, patients received either RELA 100-200 mg for 12 weeks or RELA 250-400 mg for 16 weeks; coagulation markers were assessed in 34 patients throughout the study. In the surgical study, baseline (BL) mean 24-h urinary free cortisol (UFC) was 615.6 mcg/day (by immunoassay; 2.1x upper limit of normal [ULN]); mean and median time to hemostasis assessment after remission were 6.2 and 6 mos, respectively. Significant mean changes from BL were observed in activated partial thromboplastin time (aPTT; +2.0 sec, P=0.031), factor VIII (fVIII; -24.2%, P=0.044), and von Willebrand factor (vWF; -20.6%, P=0.018), whereas platelet count was unchanged. In the RELA study, BL mean UFC was 211.9 mcg/day (by tandem mass spectrometry; 4.2x ULN). Similar to the surgical study, significant mean changes from BL to last observed visit were reported in aPTT (+1.5 sec, P=0.046), fVIII (-18.9%, P=0.022), and platelet count (-68.8*109/L, P&amp;lt;0.0001), while vWF was unchanged. Significant improvements in other coagulation factors, eg, fIX and fX, were seen in patients with abnormal values at BL. These studies showed that coagulation markers in patients with CS improve 6 mos after curative surgery, and that treatment with RELA may have similar effects after 3-4 mos. The previously observed transient increase in fVIII immediately after surgery was absent with RELA, where negative mean changes from BL were seen throughout the study. This is presumably due to the less abrupt reduction of cortisol activity with RELA compared to surgery. RELA’s effects on hypercoagulopathy support further investigation of preoperative use and in patients with CS who are not eligible for surgery. Presentation: Thursday, June 15, 2023

Withaferin A: A potential selective glucocorticoid receptor modulator with anti-inflammatory effect.

Glucocorticoids have been widely applied to various clinical treatment, however some serious side effects may occur during the treatment. It is widely known that glucocorticoids produce a marked effect through binding to glucocorticoid receptor (GR). As withaferin A can provide multiple health benefits, this work aims to confirm withaferin A as a potential selective GR modulator with anti-inflammatory effect. Fluorescence polarization assay confirmed that withaferin A could steadily bind to GR with an IC50 value of 203.80 ± 0.36 μM. Meanwhile, glucocorticoid receptor translocation of withaferin A was measured by nuclear fractionation assay. Dual luciferase reporter assay showed that withaferin A did not activate GR transcription. Furthermore, withaferin A decreased the GR-related protein expression with less side effects. The result of molecular docking showed that hydrogen-bonding and hydrophobic interactions contributed to the binding of withaferin A with GR. In addition, the GR-withaferin A complex maintained a stable binding throughout the dynamics simulation process. Enzyme-linked immunosorbent assay showed that withaferin A inhibited the production of cytokines, confirming its anti-inflammatory effect. These findings indicate that withaferin A is a potential selective GR modulator and this work may provide a research basis for developing dietary supplements and nutraceuticals against inflammation.