The Role of Glucocorticoid Receptor Signaling in Bladder Cancer Progression

Patient-derived organoids identify tailored therapeutic options and determinants of plasticity in sarcomatoid urothelial bladder cancer

Sarcomatoid Urothelial Bladder Cancer (SARC) is a rare and aggressive histological subtype of bladder cancer for which therapeutic options are limited and experimental models are lacking. Here, we report the establishment of a long-term 3D organoid-like model derived from a SARC patient (SarBC-01). SarBC-01 emulates aggressive morphological, phenotypical, and transcriptional features of SARC and harbors somatic mutations in genes frequently altered in sarcomatoid tumors such as TP53 (p53) and RB1 (pRB). High-throughput drug screening, using a library comprising 1567 compounds in SarBC-01 and conventional urothelial carcinoma (UroCa) organoids, identified drug candidates active against SARC cells exclusively, or UroCa cells exclusively, or both. Among those, standard-of-care chemotherapeutic drugs inhibited both SARC and UroCa cells, while a subset of targeted drugs was specifically effective in SARC cells, including agents targeting the Glucocorticoid Receptor (GR) pathway. In two independent patient cohorts and in organoid models, GR and its encoding gene NR3C1 were found to be significantly more expressed in SARC as compared to UroCa, suggesting that high GR expression is a hallmark of SARC tumors. Further, glucocorticoid treatment impaired the mesenchymal morphology, abrogated the invasive ability of SARC cells, and led to transcriptomic changes associated with reversion of epithelial-to-mesenchymal transition, at single-cell level. Altogether, our study highlights the power of organoids for precision oncology and for providing key insights into factors driving rare tumor entities.

Chronic prednisone, metformin, and nonsteroidal anti-inflammatory drug use and clinical outcome in a cohort of bladder cancer patients undergoing radical cystectomy in Québec, Canada

BACKGROUND

Studies have suggested a positive association between bladder cancer (BC) outcome and comedication use, including nonsteroidal anti-inflammatory drugs (NSAID), metformin, and prednisone use. To validate these associations, we evaluated whether these medications were associated with clinical outcome in a Canadian cohort of BC patients.

METHODS

This is a retrospective cohort study on BC patients undergoing radical cystectomy (RC) in Québec province in 2000-2015, as registered in the provincial health administration databases. Medication use was considered chronic when prescribed for ≥ 1 year. Overall (OS), disease-specific (DSS) and recurrence-free (RFS) survival were compared using multivariable Cox proportional hazards models. Covariates included age, Charlson's comorbidity index, region of residence, year of RC, distance to hospital, hospital type, hospital and surgeon annual RC volume, neoadjuvant chemotherapy use, and type of bladder diversion, as well as mutual adjustment for concomitant comedication use (statins, NSAIDs, metformin, and prednisone).

RESULTS

Of 3742 patients included, 293, 420, and 1503 patients chronically used prednisone, metformin, and NSAIDs before surgery, respectively. In multivariable analyses, preoperative prednisone use was associated with improved OS (HR 0.67, 95%CI 0.55-0.82), DSS (HR 0.58, 95%CI 0.45-0.76), and RFS (HR 0.61, 95%CI 0.47-0.78). Patients who chronically used metformin preoperatively had a worse OS (HR 1.29, 95%CI 1.07-1.55), DSS (HR 1.38, 95%CI 1.10-1.72), and RFS (HR 1.41, 95%CI 1.13-1.74). Preoperative, chronic NSAID use was not significantly associated with all clinical outcomes, with adjusted HRs for OS, DSS, and RFS of 1.10 (95%CI 0.95-1.27), 1.24 (95%CI 1.03-1.48), and 1.22 (95%CI 1.03-1.45), respectively. Directionality of findings was similar when stratifying by comedication use in the year following surgery. Results were similar after propensity-score matching too.

CONCLUSIONS

In our Canadian cohort of BC undergoing RC, chronic prednisone use was associated with improved clinical outcomes, while metformin and NSAID were not.

CmP signaling network unveils novel biomarkers for triple negative breast cancer in African American women

Breast cancer is the most diagnosed cancer worldwide and remains the second leading cause of cancer death. While breast cancer mortality has steadily declined over the past decades through medical advances, an alarming disparity in breast cancer mortality has emerged between African American women (AAW) and Caucasian American women (CAW). New evidence suggests more aggressive behavior of triple-negative breast cancer (TNBC) in AAW may contribute to racial differences in tumor biology and mortality. Progesterone (PRG) can exert its cellular effects through either its classic, non-classic, or combined responses through binding to either classic nuclear PRG receptors (nPRs) or non-classic membrane PRG receptors (mPRs), warranting both pathways equally important in PRG-mediated signaling. In our previous report, we demonstrated that the CCM signaling complex (CSC) consisting of CCM1, CCM2, and CCM3 can couple both nPRs and mPRs signaling cascades to form a CSC-mPRs-PRG-nPRs (CmPn) signaling network in nPR positive(+) breast cancer cells. In this report, we furthered our research by establishing the CSC-mPRs-PRG (CmP) signaling network in nPR(-) breast cancer cells, demonstrating that a common core mechanism exists, regardless of nPR(+⁣/⁣-) status. This is the first report stating that inducible expression patterns exist between CCMs and major mPRs in TNBC cells. Furthermore, we firstly show mPRs in TNBC cells are localized in the nucleus and participate in nucleocytoplasmic shuttling in a coordinately synchronized fashion with CCMs under steroid actions, following the same cellular distribution as other well-defined steroid hormone receptors. Finally, for the first time, we deconvoluted the CmP signalosome by using systems biology and TNBC clinical data, which helped us understand key factors within the CmP network and identify 6 specific biomarkers with potential clinical applications associated with AAW-TNBC tumorigenesis. These novel biomarkers could have immediate clinical implications to dramatically improve health disparities among AAW-TNBCs.

Dexamethasone Reduces Cell Adhesion and Migration of T47D Breast Cancer Cell Line

BACKGROUND

Aberrant expression of cell adhesion molecules and matrix metalloproteinase (MMPs) plays a pivotal role in tumor biological processes including progression and metastasis of cancer cells. Targeting these processes and detailed understanding of their underlying molecular mechanism is an essential step in cancer treatment. Dexamethasone (Dex) is a type of synthetic corticosteroid hormone used as adjuvant therapy in combination with current cancer treatments such as chemotherapy in order to alleviate its side effects like acute nausea and vomiting. Recent evidences have suggested that Dex may have antitumor characteristics.

OBJECTIVE

Dex affects the migration and adhesion of T47D breast cancer cells as well as cell adhesion molecules e.g., cadherin and integrin, and MMPs by regulating the expression levels of associated genes.

METHODS

In this study, we evaluated the cytotoxicity of Dex on the T47D breast cancer cell line through MTT assay. Cell adhesion assay and wound healing assay were performed to determine the impact of Dex on cell adhesion and cell migration, respectively. Moreover, real-time PCR was used to measure the levels of α and β integrin, E-cadherin, N-cadherin, MMP-2, and MMP-9.

RESULTS

Dex decreased the viability of T47D cells in a time and dose-dependent manner. Cell adhesion and migration of T47D cells were reduced upon Dex treatment. The expression of α and β integrin, E-cadherin, N-cadherin, MMP-2, and MMP-9 were altered in response to the Dex treatment.

CONCLUSION

Our findings demonstrated that Dex may have a role in the prevention of metastasis in this cell line.

The Role of Steroid Hormone Receptors in Urothelial Tumorigenesis

Preclinical and/or clinical evidence has indicated a potential role of steroid hormone-mediated signaling pathways in the development of various neoplastic diseases, while precise mechanisms for the functions of specific receptors remain poorly understood. Specifically, in urothelial cancer where sex-related differences particularly in its incidence are noted, activation of sex hormone receptors, such as androgen receptor and estrogen receptor-β, has been associated with the induction of tumor development. More recently, glucocorticoid receptor has been implied to function as a suppressor of urothelial tumorigenesis. This article summarizes and discusses available data suggesting that steroid hormone receptors, including androgen receptor, estrogen receptor-α, estrogen receptor-β, glucocorticoid receptor, progesterone receptor and vitamin D receptor, as well as their related signals, contribute to modulating urothelial tumorigenesis.

Dexamethasone inhibits pancreatic tumor growth in preclinical models: Involvement of activating glucocorticoid receptor

Glucocorticoid receptor (GR) modulates extensive biological and pathological processes including tumor progression through diverse mechanisms. The regulatory effects of dexamethasone (DEX), a synthetic glucocorticoid, as well as its interaction with GR have been recognized beyond hematologic cancers. In the present study, we investigated the anti-cancer efficacy of DEX and the correlation with GR in pancreatic cancer, a most aggressive malignancy threatening human health. The differential levels of GR expression were examined in two human pancreatic cancer cell lines, PANC-1 and SW1990, as well as in xenografts and patient tumor tissues. DEX significantly inhibited colony formation, migration, and tumor growth of PANC-1 cells expressing abundant GR. The underlying mechanisms involved suppression of nuclear factor κB (NF-κB) phosphorylation and down-regulation of epithelial-to-mesenchymal transition (EMT), interleukin 6 (IL-6) and vascular endothelial growth factor (VEGF). The anti-cancer effects of DEX were partially reversed by GR silencing or combinational administration of GR antagonist, RU486. The dose-dependent efficacy of DEX in tumor growth inhibition was also demonstrated in a GR-positive patient-derived xenograft model along with safety in mice. DEX was less potent, however, in SW1990 cells with poor GR expression. Our findings suggest that DEX effectively inhibits pancreatic tumor growth partially through GR activation. The potential correlation between GR expression and anti-cancer efficacy of DEX may have some clinical implications.

Compound A inhibits urothelial tumorigenesis via both the androgen receptor and glucocorticoid receptor signaling pathways

Recent preclinical evidence has indicated that both androgen receptor (AR) inactivation and glucocorticoid receptor (GR) transrepression are associated with suppression of urothelial carcinogenesis. We therefore assessed the effect of a unique compound, 2-(4-acetoxyphenyl)-2-chloro-N-methylethylammonium chloride (Compound A; CpdA), which could function as an AR antagonist as well as a GR ligand, on urothelial tumorigenesis. Using the in vitro system with GR-positive non-neoplastic urothelial SVHUC cells stably expressing AR (SVHUC-AR), neoplastic transformation induced by a chemical carcinogen 3-methylcholanthrene (MCA) was inhibited similarly by an anti-androgen hydroxyflutamide and a glucocorticoid prednisone, and more strongly by CpdA. CpdA also prevented the neoplastic transformation of AR-negative MCA-SVHUC cells, which was diminished by a GR antagonist RU486, but failed to prevent that of GR knockdown MCA-SVHUC cells. In MCA-SVHUC-AR cells, CpdA significantly reduced the expression levels of oncogenes (c-Fos/c-Jun/c-Myc) and induced those of tumor suppressors (UGT1A/p21/p27/p53/PTEN). Additionally, a potent carcinogen N-butyl-N-(4-hydroxybutyl)nitrosamine induced bladder cancer in all of 8 mock-treated mice versus 4 (50%) of flutamide-treated (P = 0.021), 4 (50%) of prednisone-treated (P = 0.021), or 2 (25%) of CpdA-treated (P = 0.002) animals. Finally, CpdA was found to reduce AR transactivation and selectively induce GR transrepression (i.e. suppression of NF-κB transactivation and expression of its regulated genes), but not GR transactivation (i.e. activation of glucocorticoid-response element-mediated transcription and expression of its targets) in SVHUC cells. These findings suggest that CpdA suppresses urothelial tumorigenesis via both the AR and GR pathways, which may consequently provide an effective option of chemoprevention for bladder cancer, especially in patients with superficial disease following transurethral surgery.

Role of glucocorticoid signaling in urothelial tumorigenesis: Inhibition by prednisone presumably through inducing glucocorticoid receptor transrepression

Glucocorticoids, including dexamethasone (DEX) and prednisone (PRED), have been prescribed in patients with neoplastic disease as cytotoxic agents or comedications. Nonetheless, it remains uncertain whether they have an impact on the development of bladder cancer. We, therefore, assessed the functional role of the glucocorticoid-mediated glucocorticoid receptor (GR) signaling in urothelial tumorigenesis. Tumor formation was significantly delayed in xenograft-bearing mice with implantation of control bladder cancer UMUC3 cells or nonneoplastic urothelial SVHUC cells undergoing malignant transformation induced by a chemical carcinogen 3-methylcholanthrene (MCA), compared with respective GR knockdown xenografts. Using the in vitro system with MCA-SVHUC cells, we screened 11 GR ligands, including DEX, and found significant inhibitory effects of PRED on their neoplastic transformation. The effects of PRED were restored by a GR antagonist RU486 in GR-positive MCA-SVHUC cells, while PRED failed to inhibit the neoplastic transformation of GR knockdown cells. Significant decreases in the expression levels of oncogenes (c-Fos/c-Jun) and significant increases in those of a tumor suppressor UGT1A were seen in MCA-SVHUC-control cells (vs GR-short hairpin RNA) or PRED-treated MCA-SVHUC-control cells (vs mock). In addition, N-butyl-N-(4-hydroxybutyl) nitrosamine induced bladder cancer in all of eight mock-treated mice vs seven (87.5%) of DEX-treated (P = .302) or four (50%) of PRED-treated (P = .021) animals. Finally, DEX was found to considerably induce both transactivation (activation of glucocorticoid-response element mediated transcription and expression of its targets) and transrepression (suppression of nuclear factor-kappa B transactivation and expression of its regulated genes) of GR in SVHUC cells, while PRED more selectively induced GR transrepression. These findings suggest that PRED could prevent urothelial tumorigenesis presumably via inducing GR transrepression.

The Role of Nuclear Receptors in Prostate Cancer

The nuclear receptor (NR) superfamily consists of 48 members that are divided into seven subfamilies. NRs are transcription factors that play an important role in a number of biological processes. The NR superfamily includes androgen receptor, which is a key player in prostate cancer pathogenesis, suggesting the functional roles of other NRs in prostate cancer. The findings on the roles of NRs in prostate cancer thus far have shown that several NRs such as vitamin D receptor, estrogen receptor β, and mineralocorticoid receptor play antioncogenic roles, while other NRs such as peroxisome proliferator-activated receptor γ and estrogen receptor α as well as androgen receptor play oncogenic roles. However, the roles of other NRs in prostate cancer remain controversial or uninvestigated. Further research on the role of NRs in prostate cancer is required and may lead to the development of novel preventions and therapeutics for prostate cancer.