Clinical and therapeutic implications of sex steroid hormone receptor status in urothelial bladder cancer

Correlation between androgen and estrogen receptor expression and clinicopathologic features in carcinoma urinary bladder

INTRODUCTION

The molecular mapping of cancers by the Cancer Genome Atlas Project has accelerated the quest for new therapeutic targets for urinary bladder cancer, including sex steroid receptors. Previous studies have demonstrated conflicting results on their relationship with bladder cancer, and there is sparse data on their expression in the Indian population. The aim of our study is to examine the expression of androgen receptors (AR) and estrogen receptors (ERα and ERβ) in patients with bladder cancer and their correlation with clinicopathologic features.

MATERIALS AND METHODS

In this retrospective cohort study, a total of 132 patients, who were surgically managed for urinary bladder mass by transurethral resection or radical cystectomy in our institute, with transitional cell carcinoma on histopathology and with at least two years of follow-up were included. Their demographic and treatment details were obtained, histopathology blocks were retrieved and immunohistochemical staining for androgen and estrogen receptors was performed. Then, the relationship between their expression and clinicopathologic features was studied.

RESULTS

A total of 3.79% of patients showed estrogen receptor alpha positivity, 51.52% estrogen receptor beta positivity and 63.64% androgen receptor positivity. No statistically significant correlation was found between age of patients (p = 0.75/0.52/0.87), tumour stage and grade (0.71/0.3/0.21), pathological variant (p = 1/0.58/0.38) and overall survival (p = 0.70/0.052/0.45 for NMIBC and p = 0.82/0.36/0.22) and estrogen receptor alpha, estrogen receptor beta and androgen receptor-positive status, respectively. Estrogen receptor beta positivity was significantly higher in patients with unifocal (p = 0.015) and small tumours (< 5 cm) (p = 0.03), and its expression was associated with better disease-free survival (DFS) (p = 0.046) in patients of non-muscle invasive bladder cancer (NMIBC).

CONCLUSION

Our study has the largest sample size conducted on Indian population with results differing from previous studies conducted on western population. Estrogen receptor beta expression was significantly associated with small unifocal tumours and better DFS. Estrogen receptor alpha and androgen receptor expression were not found to be associated with the clinicopathologic features of the study population.

Identification of Potential Key Genes Linked to Gender Differences in Bladder Cancer Based on Gene Expression Omnibus (GEO) Database

Background

Growing evidence strongly indicates pivotal roles of gender differences in the occurrence and survival rate of patients with bladder cancer, with a higher incidence in males and poorer prognosis in females. Nevertheless, the molecular basis underlying gender-specific differences in bladder cancer remains unknown. The current study has tried to detect key genes contributing to gender differences in bladder cancer patients.

Materials and Methods

The gene expression profile of GSE13507 was firstly obtained from the Gene Expression Omnibus (GEO) database. Further, differentially expressed genes (DEGs) were screened between males and females using R software. Protein-protein interactive (PPI) network analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Kaplan-Meier survival analyses were also performed.

Results

We detected six hub genes contributing to gender differences in bladder cancer patients, containing IGF2, CCL5, ASPM, CDC20, BUB1B, and CCNB1. Our analyses demonstrated that CCNB1 and BUB1B were upregulated in tumor tissues of female subjects with bladder cancer. Other genes, such as IGF2 and CCL5, were associated with a poor outcome in male patients with bladder cancer. Additionally, three signaling pathways (focal adhesion, rheumatoid arthritis, and human T-cell leukemia virus infection) were identified to be differentially downregulated in bladder cancer versus normal samples in both genders.

Conclusion

Our findings suggested that gender differences may modulate the expression of key genes that contributed to bladder cancer occurrence and prognosis.

Impact of Androgen Suppression Therapy on the Risk and Prognosis of Bladder Cancer: A Systematic Review and Meta-Analysis

Purpose

The purpose of this study was to summarize the existing evidence and develop a comprehensive systematic review of the impact of androgen suppression therapy (AST) on the incidence or clinical outcomes of bladder cancer.

Methods

We systematically searched the PubMed and Embase databases from inception to June 20, 2021 to identify all observational studies examining the incidence or clinical outcomes of bladder cancer in patients who received AST. AST is defined as the use of 5-alpha reductase inhibitors (5-ARIs) or androgen deprivation therapy (ADT).

Results

A total of 18 observational studies were included. Our results showed that AST was not significantly associated with a reduced risk of BCa incidence (OR: 0.92, 95% CI: 0.68–1.24) compared with the lack of AST. The subgroup analysis revealed that finasteride use was significantly associated with a reduction in the risk of BCa incidence (OR: 0.75, 95% CI: 0.64–0.88). Recurrence-free survival (RFS) was improved among AST users compared with nonusers (HR: 0.68, 95% CI: 0.48–0.95), while no significant difference between AST users versus nonusers was identified for cancer-specific survival (CSS), overall survival (OS) or progression-free survival (PFS).

Conclusion

Current evidence indicates that therapy with finasteride may represent a potential strategy aimed at reducing BCa incidence. Moreover, AST has a beneficial effect on the recurrence of bladder cancer. Further well-designed randomized trials or cohort studies with better characterized study populations are needed to validate our preliminary findings.

Systematic Review Registration

International Prospective Register of Systematic Reviews database [https://www.crd.york.ac.uk/PROSPERO/], identifier CRD42021261685.

The Inequality of Females in Bladder Cancer

Urinary bladder cancer is worldwide one of the most diagnosed and costly types of cancer. One puzzle in the bladder cancer diagnosis is the disproportional relationship between genders. Males are more likely to be diagnosed with bladder cancer whereas females typically are diagnosed with more adverse disease and worse prognosis, which has led to speculation of the potential role of sex hormones and their receptors in this disease. Estrogen receptors are present in the human bladder, and their role in bladder cancer oncogenesis is increasingly becoming a focus for researchers around the world. This mini-review aims to give a brief overview of the status of female bladder cancer, and to which extend the sex hormones receptors play a role in this. A literature search was performed and included all female original studies on bladder cancer and hormone receptors. Estrogen-receptor alpha seems to be anti-oncogenic whereas estrogen-receptor beta is exhibiting its function pro-oncogenic. The receptor functions may be exercised through mRNA transcriptions and enzymes. Epidemiological studies indicate a potential increase in incidence of bladder cancer for females with earlier age at menopause, and clinical trials are investigating Tamoxifen as a potential treatment in bladder cancer. Increasing evidence supports the theory of bladder cancer development and progression as being partly hormone-dependent. This can lead to a change in conceptual background of bladder cancer etiology and development in the future. Further studies are required to more precise map the use of anti-hormonal drugs in the treatment of this cancer.

Bisphenol A Alters the Energy Metabolism of Stromal Cells and Could Promote Bladder Cancer Progression

Simple Summary

Our research brings new insight on the potential impact of bisphenol A on bladder cancer progression. By evaluating the effects of bisphenol A on the stromal environment of bladder cancer, we aimed to demonstrate that this endocrine disruptor could promote bladder cancer invasion through alteration of the energy metabolism of stromal cells, specifically on bladder fibroblasts and cancer-associated fibroblasts. These findings could modify the understanding of bladder cancer since bladder tissue is not recognized as a hormone-sensitive tissue. Consequently, our study suggests that endocrine disruptors, such as bisphenol A, could impact bladder cancer progression.

Abstract

Bisphenol A (BPA) is an endocrine-disrupting molecule used in plastics. Through its release in food and the environment, BPA can be found in humans and is mostly excreted in urine. The bladder is therefore continuously exposed to this compound. BPA can bind to multiple cell receptors involved in proliferation, migration and invasion pathways, and exposure to BPA is associated with cancer progression. Considering the physiological concentrations of BPA in urine, we tested the effect of nanomolar concentrations of BPA on the metabolism of bladder fibroblasts and cancer-associated fibroblasts (CAFs). Our results show that BPA led to a decreased metabolism in fibroblasts, which could alter the extracellular matrix. Furthermore, CAF induction triggered a metabolic switch, similar to the Warburg effect described in cancer cells. Additionally, we demonstrated that nanomolar concentrations of BPA could exacerbate this metabolic switch observed in CAFs via an increased glycolytic metabolism, leading to greater acidification of the extracellular environment. These findings suggest that chronic exposure to BPA could promote cancer progression through an alteration of the metabolism of stromal cells.

Endocrine-disrupting effects of bisphenols on urological cancers

Bisphenols are endocrine-disrupting chemicals found in a broad range of products that can modulate hormonal signalling pathways and various other biological functions. These compounds can bind steroid receptors, e.g. estrogen and androgen receptors, expressed by numerous cells and tissues, including the prostate and the bladder, with the potential to alter their homeostasis and normal physiological functions. In the past years, exposure to bisphenols was linked to cancer progression and metastasis. As such, recent pieces of evidence suggest that endocrine-disrupting chemicals can lead to the development of prostate cancer. Moreover, bisphenols are found in the urine of the wide majority of the population. They could potentially affect the bladder's normal physiology and cancer development, even if the bladder is not recognized as a hormone-sensitive tissue. This review will focus on prostate and bladder malignancies, two urological cancers that share standard carcinogenic processes. The description of the underlying mechanisms involved in cell toxicity, and the possible roles of bisphenols in the development of prostate and bladder cancer, could help establish the putative roles of bisphenols on public health.

Inhibition of Androgen Signalling Improves the Outcomes of Therapies for Bladder Cancer: Results from a Systematic Review of Preclinical and Clinical Evidence and Meta-Analysis of Clinical Studies

Bladder cancer (BCa) is an endocrine-related tumour and the activation of androgen signalling pathways may promote bladder tumorigenesis. We summarized the available preclinical and clinical evidence on the implications of the manipulation of androgen signalling pathways on the outcomes of BCa therapies. A systematic review was performed in December 2020. We included papers that met the following criteria: original preclinical and clinical research; evaluating the impact of androgen signalling modulation on the outcomes of BCa therapies. Six preclinical and eight clinical studies were identified. The preclinical evidence demonstrates that the modulation of androgen receptor-related pathways has the potential to interfere with the activity of the Bacillus Calmette Guerin, doxorubicin, cisplatin, gemcitabine, and radiotherapy. The relative risk of BCa recurrence after transurethral resection of the bladder tumour (TURBT) is significantly lower in patients undergoing therapy with 5 alpha reductase inhibitors (5-ARIs) or androgen deprivation therapy (ADT) (Relative risk: 0.50, 95% CI: 0.30–0.82; p = 0.006). Subgroup analysis in patients receiving 5-ARIs revealed a relative risk of BCa recurrence of 0.46 (95% CI: 0.22–0.95; p = 0.040). A significant negative association between the ratio of T1 BCa patients in treated/control groups and the relative risk of BCa recurrence was observed. Therapy with 5-ARIs may represent a potential strategy aimed at reducing BCa recurrence rate, mainly in patients with low stage disease. Further studies are needed to confirm these preliminary data.