Lower risk in parous women suggests that hormonal factors are important in bladder cancer etiology

Cardamomin Inhibits the Proliferation and Tumorigenesis of Bladder Cancer by ESR1 in PI3K/AKT Pathway

Cardamomin has been widely studied in cancer, but its role in cancer bladder cancer has not been mentioned. In this study, we validated the anti-cancer effect of cardamom and whether its potential mechanism is related to the PI3K/AKT pathway. After treating with different doses of cardamomin, the cytotoxicity was studied by CCK8. Secondly, we analyzed the effect of cardamomin on the proliferation, apoptosis and cell movement. Next, we analyzed the regulation of ESR1 by western blot and its impact on the PI3K/AKT pathway. We also transfected ESR1 overexpression and silencing vectors, and verified the transfection efficiency through RT-qPCR. Further, the specific mechanism of the drug's inhibitory effect on bladder cancer was also determined. We constructed the subcutaneous tumor model in vivo. After cardamomin administration, we mainly analyzed the positive expression of KI67 in tumor tissues by immunohistochemistry, and the apoptotic cells in tumor tissues by TUNEL, and related proteins in PI3K/AKT pathway by western blot. In this paper, cardamomin inhibited cell proliferation and invasion ability, blocked the transition of G0/G1 phase to S phase, and increased apoptotic rate of 5637 and HT1376 cells, as well as raised ESR1 expression. Cardamomin exerted anti-tumor effect through PI3K/AKT pathway. In vivo animal experiments indicated the inhibitory effect of cardamomin on subcutaneous implanted tumor. Cardamomin inhibited the positive expression of KI67 and promoted the TUNEL-positive cells in tumor tissues. Consistent with in vitro assay, cardamomin increased the expression of ESR1 and downregulated the PI3K/AKT pathway. Cardamomin has a significant inhibitory effect on bladder cancer, and upregulate the expression of ESR1 in bladder cancer through PI3K/AKT.

Stranger Things: New Roles and Opportunities for Androgen Receptor in Oncology Beyond Prostate Cancer

The androgen receptor (AR) is one of the oldest therapeutic targets in oncology and continues to dominate the treatment landscape for advanced prostate cancer, where nearly all treatment regimens include some form of AR modulation. In this regard, AR remains the central driver of prostate cancer cell biology. Emerging preclinical and clinical data implicate key roles for AR in additional cancer types, thereby expanding the importance of this drug target beyond prostate cancer. In this mini-review, new roles for AR in other cancer types are discussed as well as their potential for treatment with AR-targeted agents. Our understanding of these additional functions for AR in oncology expand this receptor's potential as a therapeutic target and will help guide the development of new treatment approaches.

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.

The second to fourth digit ratio (2D:4D): A risk factor of bladder cancer in men

BACKGROUND

Exposure to prenatal sex steroids as indicated by the ratio of the second to fourth digit length (2D:4D) has been linked to the risk of onset of cancer, while sex steroids may expand the gender disparity in bladder cancer (BC) morbidity.

AIM

To explore the association between 2D:4D ratio and BC risk.

SUBJECTS

307 bladder cancer patients and 321 cancer-free individuals.

OUTCOME MEASURES

Relationships between 2D:4D and incidence of bladder cancer.

RESULTS

For males, a lower 2D:4D ratio of both hands was obtained in the BC group, relative to the control group (left hand: 0.940 ± 0.031 vs. 0.954 ± 0.024, t = -4.72, p < 0.001, Cohen's d = 0.491 and right hand: 0.939 ± 0.031 vs. 0.952 ± 0.022, t = -4.493, p < 0.001, Cohen's d = 0.511). In females, no differences in the 2D:4D ratio were observed between the BC and control groups (p > 0.05). Correlation analysis between 2D:4D ratio and pathological index found no correlation among the BC grade or stage (p > 0.05).

CONCLUSION

Men with BC have a lower 2D:4D ratio compared with healthy men. Therefore, having a low 2D:4D ratio is a risk factor for BC in men. Prenatal exposure to sex steroids might play a role in the etiology of BC, which could partially explain the gender disparity in the prevalence of BC.

Menstrual Factors, Reproductive History, Hormone Use, and Urothelial Carcinoma Risk: A Prospective Study in the EPIC Cohort

BACKGROUND

Urothelial carcinoma is the predominant (95%) bladder cancer subtype in industrialized nations. Animal and epidemiologic human studies suggest that hormonal factors may influence urothelial carcinoma risk.

METHODS

We used an analytic cohort of 333,919 women from the European Prospective Investigation into Cancer and Nutrition Cohort. Associations between hormonal factors and incident urothelial carcinoma (overall and by tumor grade, tumor aggressiveness, and non-muscle-invasive urothelial carcinoma) risk were evaluated using Cox proportional hazards models.

RESULTS

During a mean of 15 years of follow-up, 529 women developed urothelial carcinoma. In a model including number of full-term pregnancies (FTP), menopausal status, and menopausal hormone therapy (MHT), number of FTP was inversely associated with urothelial carcinoma risk (HR≥5vs1 = 0.48; 0.25-0.90; P trend in parous women = 0.010) and MHT use (compared with nonuse) was positively associated with urothelial carcinoma risk (HR = 1.27; 1.03-1.57), but no dose response by years of MHT use was observed. No modification of HRs by smoking status was observed. Finally, sensitivity analyses in never smokers showed similar HR patterns for the number of FTP, while no association between MHT use and urothelial carcinoma risk was observed. Association between MHT use and urothelial carcinoma risk remained significant only in current smokers. No heterogeneity of the risk estimations in the final model was observed by tumor aggressiveness or by tumor grade. A positive association between MTH use and non-muscle-invasive urothelial carcinoma risk was observed.

CONCLUSIONS

Our results support that increasing the number of FTP may reduce urothelial carcinoma risk.

IMPACT

More detailed studies on parity are needed to understand the possible effects of perinatal hormone changes in urothelial cells.

Reproductive and hormonal factors and bladder cancer risk: a prospective study and meta-analysis

Bladder cancer is three to four times more common among men than women. The objectives of this study were to explore the association between reproductive and hormonal factors and risk of bladder cancer among women using data from the Prostate, Lung, Colorectal and Ovarian (PLCO) cohort, and to perform a meta-analysis based on cohort studies. After a median of 11.6 years of follow-up, 237 incident bladder cancer cases were identified in PLCO cohort. Compared with menopause at 50-54 years, earlier menopause (< 45 years) was positively but not significantly associated with bladder cancer risk (HR 1.25, 95% CI 0.91-1.71; p = 0.176). In the meta-analysis, parous women had significantly lower bladder cancer risk than nulliparous women (pooled HR 0.79, 95% CI 0.73-0.86). In addition, menopause at an earlier age was significantly associated with a higher risk of bladder cancer (pooled HR 1.22, 95% CI 1.06-1.40). In conclusion, this study indicated a greater risk in bladder cancer among nulliparous women and among women with early menopause. Further studies are needed to understand the underlying mechanisms.

Urobiome in Gender-Related Diversities of Bladder Cancer

Bladder cancer (BC) remains the most common malignancy of urinary tract. Sex-related differences in BC epidemiology, diagnosis, therapy, and outcomes have been reported. Throughout the recent years, extensive research has been devoted to genetic and molecular alterations in BC. Apart from the molecular background, another related concept which has been speculated to contribute to gender diversities in BC is the role of urinary pathogens in bladder carcinogenesis. Microbiome studies, fueled by the availability of high-throughput DNA-based techniques, have shown that perturbation in the microbiome is associated with various human diseases. The aim of this review is to comprehensively analyze the current literature according to sex-related differences in the microbiome composition in BC.

Spotlight on gender-specific disparities in bladder cancer

Men are at a higher risk of developing bladder cancer, but women present with more advanced disease and have more unfavourable outcomes. Although epidemiologic and genetical studies have underlined the multifactorial aetiology and gender-related differences of bladder cancer, there is lack of evidence-based recommendation for gender-specific management of bladder cancer. We summarize the evidence and most recent findings on gender-specific differences in bladder cancer incidence, diagnosis, treatment and outcome, spotlighting the gender disparities in genetic and hormonal risk factors, pelvic anatomy, diagnostic setting and surgical choices. We reviewed the literature published on PubMed between 1981 and 2018. Males have a threefold to fourfold higher risk of bladder cancer as compared to females; however, women have higher stage-for-stage mortality, being diagnosed with more advanced disease, mostly due to a delay in haematuria evaluation. Numerous studies indicate an increased risk of disease recurrence or progression in women with non-muscle-invasive bladder cancer treated with trans-urethral resection, with or without intravesical chemotherapy or immunotherapy, compared to males. In particular, recent molecular evidence show that there is an excess of female Ta mutant tumours. At the time of radical cystectomy, women have a significantly longer length of hospital stay, operative time, higher blood loss and higher 90-day mortality and perioperative complication rate. Moreover, females are less likely to receive a continent diversion. Future research should guarantee greater inclusion of women in trials and focus on improving the effectiveness of therapies in women, perhaps exploring different therapeutic approaches in men and women. Specific data on functional and oncological outcomes can be analysed to define predictive factors able to guide the surgeon in decisions based on evidence. It is urgently needed to limit gender-related discrepancies in early diagnosis and treatment of bladder cancer. Public awareness and bladder cancer female patients' consciousness on gender inequalities must be similarly uprisen.

Body mass index modifies bladder cancer risk associated with low estrogen exposure among Egyptian women after menopause

PURPOSE

Investigators have reported inconsistent findings regarding associations between body mass index (BMI) and bladder cancer risk, and they have postulated that sex steroids mediate such associations. We assessed the impact of BMI on the relationship between bladder cancer risk and combinations of age at first childbirth, parity, and age at menopause, among Egyptian women.

METHODS

We used data from our multicenter case-control study of 419 cases and 786 controls in logistic regression models to estimate adjusted odds ratios (AORs) and 95% confidence intervals (CIs) of such associations.

RESULTS

Age > 18 years at first childbirth and parity ≤ 6 were significantly associated with bladder cancer risk, which was higher when both factors (AOR = 2.31, 95% CI = 1.55-3.43) and age at menopause < 45 years (AOR = 3.51, 95% CI = 1.88-6.55) were present. Early menopause was associated with higher bladder cancer risk in obese (AOR = 2.90, 95% CI = 1.40-5.98) but not normal weight women (AOR = 0.98, 95% CI = 0.58-1.65; P_interaction = 0.11), and the risk was greatest when both first childbirth at age > 18 years and parity ≤ 6 were present (AOR = 7.60, 95% CI = 1.84-31.35); however, overweight and obesity were associated with significantly lower bladder cancer risk (AOR = 0.59, 95% CI = 0.43-0.81, and AOR = 0.26, 95% CI = 0.18-0.38, respectively).

CONCLUSION

Body mass index appears to modify bladder cancer risk in Egyptian women after menopause by slightly enhancing the risk associated with low estrogen exposure among the obese only. Longitudinal studies of the BMI role in bladder malignancy in this distinctive population are required.

Trends in the incidence and mortality of transitional cell carcinoma of the bladder for the last four decades in the USA: a SEER-based analysis

BACKGROUND

Transitional cell carcinoma (TCC) accounts for around 95% of bladder cancers and is the 4th most common cancer among men and the tenth most common in women, in the US. There is a constant need to clarify current TCC incidence and mortality rates among different population groups for better clinical practice guidelines. We aimed to describe the TCC incidence and incidence-based mortality by demographic and tumor-related characteristics over the last 40 years in the US.

METHODS

We obtained data from the SEER 18 registries to study TCC cases that were diagnosed between the years 1973 and 2014. We calculated incidence rates and incidence-based mortality rates in different demographic and tumor-related characteristics and expressed rates by 100,000 person-years. We then calculated the annual changes in incidence and incidence-based mortality rates and displayed them as annual percent changes (APCs).

RESULTS

There were 182,114 patients with TCC between 1973 and 2014 in the United States. Overall incidence rates of TCC increased 0.16% (95% CI, 0.02-0.30, p = .02) per year over the study period. However, the incidence declined significantly since 2007; (95%CI,-1.89- -0.77, p < .001), except among the elderly and African Americans, which increased significantly over the study period. Overall TCC mortality rates did not change over the study period. However, since 2000 it started to decrease significantly.

CONCLUSION

TCC incidence and incidence-based mortality rates had been showing significant increases over the previous decades. However, significant declines in both incidence and incidence-based mortality rates have been observed over the recent years, except in some patients with certain racial groups. Improved understanding of the etiological and ecological factors of TCC could lead to further declines in incidence and incidence-based mortality rates.

Oral Contraceptive Use and Risks of Cancer in the NIH-AARP Diet and Health Study

Although use of oral contraceptives (OCs) is common, their influence on carcinogenesis is not fully understood. We used Cox proportional hazards models to examine OC use (never/<1 year (referent), 1-4, 5-9, ≥10 years) and development of incident cancers across body sites within the same base population: women in the prospective National Institutes of Health-AARP Diet and Health Study (enrolled 1995-1996 and followed until 2011). Adjustment for confounding varied by outcome; all models accounted for age, race, body mass index, and smoking status, and included at least 100,000 women. Any OC use conferred a 3% reduction in the risk for any cancer (hazard ratio = 0.97, 95% confidence interval: 0.95, 0.99). Expected risk reductions that strengthened with duration of use were identified for ovarian and endometrial cancers and were suggested for kidney cancer (all P for trend < 0.05). Non-Hodgkin lymphoma risk (hazard ratio = 0.79, 95% confidence interval: 0.64, 0.97) was reduced with 10 or more years of OC use. There was a 37% reduced risk for bladder cancer and 46% increased risk for pancreatic cancer among long-term OC users who were 60 years of age or younger at baseline. OC use did not influence risks for most other cancers evaluated. Given the high prevalence of use and changing formulations, additional studies are warranted to fully understand the chemopreventive effects of these medications.

Differential expression of cytokeratin 14 and 18 in bladder cancer tumorigenesis

It has been previously suggested that cytokeratins (CKs) are important diagnostic and prognostic biomarkers for urothelial lesions. Hence it is imperative to understand the expression pattern of cytokeratins during formation of papillary bladder cancer, which was the objective of the current study. Expression pattern of CK14 and CK18 were examined using immunohistochemical staining in a mice model of papillary bladder cancer. Twenty female mice were divided into two groups-group 1 (NT) and group 2, which received N-butyl- N-(4-hydroxybutyl) nitrosamine (BBN) for 20 weeks plus one week without treatment. Following histological classification of bladder lesions, CK14 and CK18 immunostaining was assessed according to its distribution and intensity. In NT animals, both basal cells and umbrella cells showed sporadic positive staining for CK14 and CK18, respectively. In BBN group, hyperplastic lesions showed significantly more CK14 and significantly less CK18 staining ( P < 0.05 in each case). Invasive carcinomas showed increased CK14 immunostaining in all epithelial layers. Cumulatively, our data indicate that altered CK14 (high) and CK18 (low) expression is perhaps an early event in bladder cancer tumorigenesis in females at least and is characteristic of both urothelial superficial pre-neoplastic and neoplastic lesions. Impact statement Studies have shown that expression of cytokeratins (CKs) or their altered distribution affects the bladder cancer pathogenesis and disease outcome, while the underlying mechanisms are not clear. The present study aims to explore the expression pattern of CK14 and CK18 during formation of papillary bladder cancer. The results showed that hyperplastic lesions showed significantly more CK14 and significantly less CK18 staining and invasive carcinomas showed increased CK14 immunostaining in all epithelial layers in N-butyl- N-(4-hydroxybutyl)nitrosamine (BBN)-induced mouse model. The results indicate that altered CK14 (high) and CK18 (low) expression is perhaps an early event in bladder cancer tumorigenesis and is characteristic of both urothelial superficial pre-neoplastic and neoplastic lesions, which may provide the early diagnosis index.

Parity and bladder cancer risk: a dose-response meta-analysis

Background

Multiple studies have reported evidence of an inverse association between parity and bladder cancer risk. However, a comprehensive and quantitative assessment of this association has never been conducted. We conducted this study to clarify this issue.

Methods

Systematic search of PubMed and Embase was performed to identify all the studies. Studies were selected based on strict screening with inclusion and exclusion criteria. Summary relative risks (RR) with 95% confidence intervals (CI) were calculated by using a fixed-effect model, and the generalized least squares trend estimation was employed to compute study-specific RR and 95% CI per live birth increase. Heterogeneity and publication bias were also evaluated.

Results

Twelve studies (6,214 cases and 2,693,350 non-cases) were eligible in this meta-analysis. The pooled RR of bladder cancer for parous versus nulliparous women was 0.76 (95% CI: 0.70–0.82). Results were similar in the studies that adjusted for BMI(RR = 0.66; 95% CI: 0.53–0.81), cigarette smoking (RR = 0.67; 95% CI: 0.57–0.79), and age (RR = 0.77; 95% CI: 0.71–0.84). The dose-response meta-analysis showed a lower bladder cancer risk (RR = 0.95; 95% CI: 0.92–0.98) for each live birth increase in parous women. No evidence of publication bias or significant heterogeneity was detected in the above-mentioned analyses.

Conclusions

The finding from current meta-analysis suggest that parity may be related to decreased risk of bladder cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-3023-5) contains supplementary material, which is available to authorized users.

Parity, Age at First Birth, and Risk of Death from Bladder Cancer: A Population-Based Cohort Study in Taiwan

The evidence is limited on the relationship between reproductive factors and bladder cancer (BC). We studied 1,292,462 women who had a first and singleton delivery between 1 January 1978 and 31 December 1987. Each woman in the study cohort was tracked from their first childbirth to 31 December 2009. Vital status of the women was determined by crosswalking records with a computerized mortality database. We used Cox proportional hazard regression models to estimate the hazard ratios (HRs) of death from BC associated with maternal age at first birth and parity. The data showed 63 BC deaths during 34,980,246 person-years of follow-up. BC mortality rate was 0.90 cases for every 100,000 person-years. Compared with women who gave birth under the age of 23, the adjusted HR was 1.24 (95% confidence interval (CI) = 0.66–2.35) for women who gave birth between age 23 and 26 and 2.30 (95% CI = 1.21–4.39) for women who gave birth over the age of 26. Increasing age at first birth (p for trend = 0.01) is associated with a trend in increasing risk of BC mortality. Relative to women who had a single childbirth, the adjusted HRs were 1.17 (95% CI = 0.51–2.69) for women who gave birth to two children, and 1.31 (95% CI = 0.56–3.10) for women with three or more childbirths, respectively. These results were not statistically significant. Study results suggests that giving birth at an early age may confer a protective effect on the risk of death from BC.

Expression of Estrogen Receptor Beta Predicts Oncologic Outcome of pT3 Upper Urinary Tract Urothelial Carcinoma Better Than Aggressive Pathological Features

Upper urinary tract urothelial carcinoma (UT-UC) is rare and treatment options or prognostic markers are limited. There is increasing evidence indicating that urothelial carcinoma may be an endocrine-related cancer. The aim of this study was to analyze the prognostic effect of estrogen receptor beta (ERβ) on the outcome of UT-UC. From 2005 to 2012, this study included 105 patients with pT3 UT-UC. Perioperative factors, pathological features, and ERβ immunostaining were reviewed and prognostic effects were examined by multivariate analysis. This study divided patients into either the ERβ-high (n = 52) or ERβ-low (n = 53) group and analyzed their oncologic outcomes. All pathological features except infiltrating tumor architecture (significantly higher incidence in ERβ-low group, p = 0.004) are symmetric in both groups. Low ERβ expression was significantly correlated with local recurrence and distant metastasis in univariate analysis (p = 0.035 and 0.004, respectively) and multivariate analysis (p = 0.05 and 0.008, respectively). Cell line study also proved that knock down of ERβ cause less UTUC proliferation and migration. In addition, ERβ agonist also enhanced the cytotoxic and migration inhibition effect of cisplatin and ERβ antagonist cause the UTUC cell more resistant to cisplatin. This result may help identify patients in need of adjuvant therapy or develop potential targeted therapy.

Gender differences in incidence and outcomes of urothelial and kidney cancer

A gender discrepancy exists in the incidence of both urothelial and kidney carcinomas, with more men presenting with these cancers than women. Men have a threefold greater risk of developing bladder cancer than women, but female gender has been identified as an independent adverse prognostic factor for both recurrence and progression of this disease. In particular, women with bladder cancer are often diagnosed with a higher tumour stage than men. Conclusive data on the influence of gender on outcomes of patients with upper tract urothelial carcinoma are currently lacking, although men seem to have a higher disease incidence, whereas survival outcomes might be independent of gender. Patients with renal cell carcinoma are more often men and they typically have larger tumours and higher stage and grade disease than women with this cancer. Smoking habits, tumour biology, occupational risk factors and sex steroid hormones and their receptors could have a role in these observed gender disparities. The majority of data support the theory that gender influences incidence and prognosis of urothelial and kidney cancers; men and women are different genetically and socially, making the consideration of gender a key factor in the clinical decision-making process. Thus, the inclusion of this variable in validated prognostic tables and nomograms should be discussed as a matter of importance.

Sex differences in the MB49 syngeneic, murine model of bladder cancer

OBJECTIVE

The MB49 syngeneic, murine model of bladder cancer has been widely used for more than 35 years. In humans, bladder cancer is one third as prevalent in women as in men, with a trend toward lower prevalence in parous compared to nulliparous women. Our objective was to determine if the MB49 bladder cancer model reproduces the sex differences observed in humans, and to determine its sensitivity to testosterone and the pregnancy hormone, human chorionic gonadotropin (hCG).

METHODS

Male and female C57BL/6 mice were implanted with MB49 murine bladder cancer cells, and observed for tumor growth. MB49 dose responses to hCG and dihydrotestosterone were determined in vitro.

RESULTS

MB49 tumor growth was significantly greater in male mice than female mice. Pregnancy did not affect MB49 tumor growth in female mice. MB49 cells did not proliferate in response to hCG in vitro and the functional receptor for gonadotropins was absent. Dihydrotestosterone strongly stimulated growth of MB49 cells in vitro.

CONCLUSIONS

The MB49 murine model of bladder cancer reproduced some aspects of the sex differences observed in humans. Our results suggest that testosterone may stimulate MB49 cell proliferation, which may explain the more rapid MB49 tumor growth observed in male mice.

[Molecular classification of bladder cancer. Possible similarities to breast cancer]

Therapeutic decisions for breast cancer are increasingly becoming based on subtype-specific gene expression tests. For bladder cancer very similar subtypes have been identified by genome-wide mRNA analysis, which as for breast cancer differ with respect to the prognosis and response to therapy on the basis of their hormone dependency. At the DNA level, however, the type of mutations and their frequencies within the subtypes are strikingly different between bladder and breast cancers. It will be interesting to see whether possible driver mutations can serve as therapeutic targets in both indications. In contrast, the apparent hormone dependency of a substantial number of bladder carcinomas suggests that hormonal and anti-hormonal treatment can be valid therapy options similar to breast cancer. Moreover, gender-specific differences with respect to the incidence and aggressiveness of male compared to female bladder cancers can be explained by hormonal effects. Together with forthcoming immunomodulatory therapies these multiple therapy options raise and give new hope to efficiently combat this aggressive disease.

Gender and Bladder Cancer: A Collaborative Review of Etiology, Biology, and Outcomes

CONTEXT

The incidence of bladder cancer is three to four times greater in men than in women. However, women are diagnosed with more advanced disease at presentation and have less favorable outcomes after treatment.

OBJECTIVE

To review the literature on potential biologic mechanisms underlying differential gender risk for bladder cancer, and evidence regarding gender disparities in bladder cancer presentation, management, and outcomes.

EVIDENCE ACQUISITION

A literature search of English-language publications that included an analysis of the association of gender with bladder cancer was performed using Pubmed. Ninety-seven articles were selected for analysis with the consensus of all authors.

EVIDENCE SYNTHESIS

It has been shown that the gender difference in bladder cancer incidence is independent of differences in exposure risk, including smoking status. Potential molecular mechanisms include disparate metabolism of carcinogens by hepatic enzymes between men and women, resulting in differential exposure of the urothelium to carcinogens. In addition, the activity of the sex steroid hormone pathway may play a role in bladder cancer development, with demonstration that both androgens and estrogens have biologic effects in bladder cancer in vitro and in vivo. Importantly, gender differences exist in the timeliness and completeness of hematuria evaluation, with women experiencing a significantly greater delay in urologic referral and undergoing guideline-concordant imaging less frequently. Correspondingly, women have more advanced tumors at the time of bladder cancer diagnosis. Interestingly, higher cancer-specific mortality has been noted among women even after adjusting for tumor stage and treatment modality.

CONCLUSIONS

Numerous potential biologic and epidemiologic factors probably underlie the gender differences observed for bladder cancer incidence, stage at diagnosis, and outcomes. Continued evaluation to define clinical applications for manipulation of the sex steroid pathway and to improve the standardization of hematuria evaluation in women may improve future patient outcomes and reduce these disparities.

PATIENT SUMMARY

We describe the scientific basis and clinical evidence to explain the greater incidence of bladder cancer in men and the adverse presentation and outcomes for this disease in women. We identify goals for improving patient survival and reducing gender disparities in bladder cancer.

Estrogen receptor alpha prevents bladder cancer via INPP4B inhibited akt pathway in vitro and in vivo

Clinical reports show males have a higher bladder cancer (BCa) incidence than females. The sexual difference of BCa occurrence suggests that estrogen and its receptors may affect BCa development. Estrogen receptor alpha (ERα) is the classic receptor to convey estrogen signaling, however, the function of ERα in BCa development remains largely unknown. To understand the in vivo role of ERα in BCa development, we generated total and urothelial specific ERα knockout mice (ERαKO) and used the pre- carcinogen BBN to induce BCa. Earlier reports showed that ERα promotes breast and ovarian cancers in females. Surprisingly and of clinical importance, our results showed that ERα inhibits BCa development and loss of the ERα gene results in an earlier onset and higher incidence of BBN-induced in vivo mouse BCa. Supportively, carcinogen induced malignant transformation ability was reduced in ERα expressing urothelial cells as compared to ERα negative cells. Mechanism studies suggest that ERα could control the expression of INPP4B to reduce AKT activity and consequently reduce BCa cell growth. In addition, IHC staining of clinical sample analyses show that INPP4B expression, in correlation with reduced ERα, is significantly reduced in human BCa specimens. Together, this is the first report using the in vivo cre-loxP gene knockout mouse model to characterize ERα roles in BCa development. Our studies provide multiple in vitro cell studies and in vivo animal model data as well as human BCa tissue analyses to prove ERα plays a protective role in BCa initiation and growth at least partly via modulating the INPP4B/Akt pathway.

Roles of ERβ and GPR30 in Proliferative Response of Human Bladder Cancer Cell to Estrogen

Bladder cancer belongs to one of the most common cancers and is a leading cause of deaths in our society. Urothelial carcinoma of the bladder (UCB) is the main type of this cancer, and the estrogen receptors in UCB remain to be studied. Our experiment aimed to investigate the possible biological effect of 17β-estradiol on human bladder-derived T24 carcinoma cells and to indicate its related mechanisms. T24 cells were treated with various doses of 17β-estradiol, and cell proliferation was detected using MTT assays. 17β-estradiol promoted T24 cell proliferation independent of ERβ/GPR30-regulated EGFR-MAPK pathway, while it inhibited cell growth via GPR30. Furthermore, the expression levels of downstream genes (c-FOS, BCL-2, and CYCLIN D1) were increased by 17β-estradiol and this effect was independently associated with activity of the EGFR-MAPK pathway. The two estrogen receptors might be potential therapeutic targets for the treatment of bladder cancer.

The Estrogen Pathway: Estrogen Receptor-α, Progesterone Receptor, and Estrogen Receptor-β Expression in Radical Cystectomy Urothelial Cell Carcinoma Specimens

OBJECTIVE

Bladder cancer has the sixth highest incidence in the United States. Treatment of metastatic bladder cancer is difficult, and mortality is certain. There are certain pathways in cancer growth and progression that are important in bladder cancer development. Recently, the estrogen pathway has been found to be a potential target for therapy.

METHODS

We identified 410 patients treated with radical cystectomy for urothelial cell carcinoma between 1990 and 1994. We obtained representative paraffin-embedded tissue blocks for 336 (82.0%) of these cases and evaluated the expression and intensity of estrogen receptor (ER)-α, ER-β, and progesterone receptor by immunohistochemistry.

RESULTS

Among the 12 ER-α-positive cases, median tumor ER-α expression was 10% (range, 10%-50%). In contrast to ER-α, all cases were ER-β-positive. Median tumor ER-β expression was 90% (range, 20%-100%). Nearly all cases had ER-β expression of ≥ 90% (175 [55.9%] with 90% and 103 [32.9%] with 100%). However, the intensity of ER-β staining varied from focal to moderate to marked in 64 (20.5%), 167 (53.4%), and 82 (26.2%) cases, respectively. Progesterone receptor expression was noted to be negative in all cases.

CONCLUSIONS

ER-β is highly expressed in bladder cancer. Prospective validation of these data might further elucidate the utility of ER-β as a marker for prognosis or possible target for therapy.

Sex steroids and gender differences in nonmuscle invasive bladder cancer

PURPOSE OF REVIEW

To review and summarize current knowledge on gender differences and sex steroid hormones in nonmuscle invasive bladder cancer.

RECENT FINDINGS

Beyond the proven role of gender as a risk factor for the development of bladder cancer, recent studies indicate that women present with more advanced bladder cancer tumor stages than men, which may be due to differences in both bladder cancer care and biology. In addition, female gender has been identified as an independent prognostic factor for both recurrence and progression and may be associated with worse response to Bacillus Calmette-Guérin instillation therapy. Overall, sex steroid hormones and their receptors impact bladder carcinogenesis, recurrence and progression. Basic and transitional research evidence suggests that estrogens may initially protect against bladder cancer development, but later promote bladder cancer progression. Androgens, in contrast, seem to initiate and drive bladder cancer with its receptor playing a central role. Promising novel research shows a potential role of sex steroid hormones as therapeutic targets.

SUMMARY

Whereas men are more likely to develop bladder cancer, women present generally with more advanced disease and have worse oncologic outcomes even after adjusting for tumor stage. Sex steroid hormones and their receptors play an active role in bladder cancer development and progression and represent attractive therapeutic targets for gender-specific care.

Anthropometric measures and bladder cancer risk: a prospective study in the EPIC cohort

Anthropometric measures have been related to risk of several cancers. For bladder cancer, however, evidence is sparse. Comparability of existing studies is hampered by use of different obesity-measures, inadequate control for smoking, and few female cases. This study examined associations between height, weight, waist and hip circumference, waist-hip ratio, waist-height ratio, body mass index (BMI), recalled weight at age 20 and bladder cancer, and investigated effect modification by age, tumor aggressiveness and smoking. The study was conducted in the European Prospective Investigation into Cancer and Nutrition cohort, in 390,878 participants. Associations were calculated using Cox Proportional Hazards Models. During follow-up, 1,391 bladder cancers (1,018 male; 373 female) occurred. Height was unrelated to bladder cancer in both genders. We found a small but significant positive association with weight [1.04 (1.01-1.07) per 5 kilo], BMI [1.05 (1.02-1.08) per 2 units], waist circumference [1.04 (1.01-1.08) per 5 cm], waist-hip ratio (1.07 (1.02-1.13) per 0.05 unit] and waist-height ratio [1.07 (1.01-1.13) per 0.05 unit] in men. Stratification by smoking status confined associations in men to former smokers. In never smokers, we found no significant associations, suggesting residual confounding by smoking. Results did not differ with tumor aggressiveness and age. Residual analyses on BMI/waist circumference showed a significantly higher disease risk with BMI in men (p = 0.01), but no association with waist circumference. In conclusion, in this large study, height was unrelated to bladder cancer, whereas overweight was associated with a slightly higher bladder cancer risk in men. This association may, however, be distorted by residual confounding by smoking.

Estrogen receptor β (ERβ) is a novel prognostic marker of recurrence survival in non-muscle-invasive bladder cancer potentially by inhibiting cadherin switch

OBJECTIVE

The function and significance of estrogen receptor β (ERβ) in bladder cancer remains a field of hot debate. In this study, we aimed to (a) evaluate ERβ as a novel prognostic marker of recurrence free survival; and (b) digest the underlying mechanism by elucidating the relationship between ERβ expression and cadherin switch.

METHODS

We examined the expression levels of ERβ, E-cadherin and N-cadherin in 42 initial non-muscle-invasive urothelial bladder carcinomas via immunohistochemistry. Correlation analysis was performed among ERβ expression, cadherin switch and recurrence free survival. Moreover, in vitro studies were performed to validate the identified correlation using two bladder cancer cell lines RT4 and 253J. Upon stimulation with an ERβ selective agonist diarylpropionitrile, E-cadherin, N-cadherin expressions; cell migration and invasion capacity were assessed.

RESULTS

Expression of ERβ protein was seen in 34 bladder cancer cases (80.9%), and 21 (50%) specimens showed non-cadherin switch (positive E-cadherin and negative N-cadherin). ERβ expression and the non-cadherin switch are both accompanied with better recurrence free survival. Also, the least ERβ expression was observed in specimens that undergo cadherin switch. Moreover, these results were consistent with our observations in bladder cancer RT4 and 253J cell lines studies. Diarylpropionitrile stimulation resulted in an increase in E-cadherin, a decrease in N-cadherin expression and abolished cell migration and invasion.

CONCLUSION

ERβ is a prognostic marker of recurrence free rate in non-muscle-invasive bladder cancer, potentially through suppressing cadherin switch, and may act as a potential target for bladder cancer therapy.

Can reproductive characteristics predict bladder cancer in women with haematuria?

BACKGROUND

Among women with haematuria, defining individuals under high risk for bladder cancer based on reproductive factors prior to cystoscopy would be of great benefit in the management of this condition. The aim of this study was to compare age and reproductive factors such as menopausal status, parity, age at first delivery and age at the last delivery between women who have haematuria with or without bladder cancer.

MATERIALS AND METHODS

A total of 463 patients underwent diagnostic cystoscopy in Duzce University Faculty of Medicine between 1 June 2008 and 1 June 2013. Female patients who presented with persistent microscopic or macroscopic haematuria and underwent standard evaluation for haematuria including urinalysis, urine culture, urine cytology, urinary tract imaging with excretory urography or computerized tomography with contrast enhancement and endoscopic evaluation of the urethra and bladder were included in this study. Exclusion criteria were tobacco use and high risk occupations for bladder cancer such as textile, dry cleaning, painting and etc. Fourteen women had hematuria due to benign conditions, and 18 due to bladder cancer. Data were retrospectively retrieved from the medical records of Duzce University Hospital.

RESULTS

Patients with haematuria due to benign reasons did not significantly differ from patients who were found to have bladder cancer in terms of age (p=0.28), menopausal status (p=0.29), mean parity (p=0.38), being nulliparous (p=0.57), parity ≥ 3 (p=0.22), age ≤ 18 years at first delivery (p=1.00), age ≥ 30 years at last delivery (p=0.26), age ≥ 35 years at last delivery (p=0.23) and percentage of the patients with advanced age (≥ 65 years) (p=0.18).

CONCLUSIONS

It is difficult to predict a high risk for developing bladder cancer in women with haematuria based solely on reproductive factors.

Reproductive factors and menopausal hormone therapy and bladder cancer risk in the NIH-AARP Diet and Health Study

The incidence of bladder cancer among women is at least one-third to one-fourth that observed among men in many countries. Even after accounting for known risk factors, the reason for this gender disparity remains unexplained. We conducted a comprehensive evaluation of reproductive factors and exogenous hormone use with a primary focus on menopausal hormone therapy use and risk of bladder cancer in women in the NIH-AARP Diet and Health Study. Reproductive and hormonal factors were ascertained on the baseline questionnaire in 1995-1996 among 201,492 females who were followed until December 31, 2006. During follow-up, 651 cases of bladder cancer were diagnosed. A subset of women provided detailed information on use of MHT in a second questionnaire in 1996-1997. In this analysis, 127,361 females were followed through June 30, 2002 and 198 incident bladder cancer cases were identified. Cox proportional hazard models, adjusted for smoking status, cigarettes per day and body mass index using age as the time metric, were used to obtain hazard ratios (HRs). A reduced risk was observed among parous women (HR=0.76; 95% CI 0.62-0.93) and women who reported late age at menarche (≥15 years) (HR=0.57; 95% CI 0.39-0.84). Women who reported ever using estrogen and progestin therapy had a decreased risk (HR=0.53; 95% CI: 0.34-0.83) compared with women who did not report MHT use. No association was observed for estrogen only users (HR=0.82; 95% CI: 0.58-1.15). Our results suggest a putative role for sex hormones in the etiology of bladder cancer among women.

Chemoprevention of BBN-Induced Bladder Carcinogenesis by the Selective Estrogen Receptor Modulator Tamoxifen

Bladder cancer is the fifth most frequent tumor in men and ninth in women in the United States. Due to a high likelihood of recurrence, effective chemoprevention is a significant unmet need. Estrogen receptors (ERs), primarily ERβ, are expressed in normal urothelium and urothelial carcinoma, and blocking ER function with selective ER modulators such as tamoxifen inhibits bladder cancer cell proliferation in vitro. Herein, the chemoprotective potential of tamoxifen was evaluated in female mice exposed to the bladder-specific carcinogen, N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). Carcinogen treatment resulted in a 76% tumor incidence and increased mean bladder weights in comparison to controls. In contrast, mice receiving tamoxifen concurrent (8-20 weeks) or concurrent and subsequent (8-32 weeks) to BBN administration had no change in bladder weight and only 10% to 14% incidence of tumors. Non-muscle-invasive disease was present in animals treated with tamoxifen before (5-8 weeks) or after (20-32 weeks) BBN exposure, while incidence of muscle-invasive bladder carcinoma was reduced. ERβ was present in all mice and thus is a potential mediator of the tamoxifen chemoprotective effect. Surprisingly, ERα expression, which was detected in 74% of the mice exposed to BBN alone but not in any controlmice, was correlated with tumor incidence, indicating a possible role for this receptor in carcinogen-induced urothelial tumorigenesis. Thus, these data argue that both ERα and ERβ play a role in modulating carcinogen-induced bladder tumorigenesis. Administration of tamoxifen should be tested as a chemopreventive strategy for patients at high risk for bladder cancer recurrence.

Estrogen receptor-β expression and pharmacological targeting in bladder cancer

A role for estrogen signaling in urothelial carcinoma of the bladder (UCB) is suggested to be associated with more advanced disease with worse outcomes in women. Estrogen receptor β (ERβ) is the predominant receptor in bladder tissues. We aimed to ascertain whether ERβ correlates with clinicopathological predictors of aggressive bladder cancer and worse survival outcomes. ERβ was measured by immunohistochemistry in malignant and adjacent benign bladder tissues in patients (N=72) with UCB who underwent radical cystectomy. ERβ expression was tested for statistical association with clinicopathological variables and patient survival. ERβ expression was determined in bladder cancer cell lines, and the effects of the selective estrogen modulator tamoxifen and the ERβ agonist diarylpropionitrile on cell growth were determined. The ERβ level was significantly higher in malignant vs. benign urothelium (P<0.001) and was strongly associated with aggressive tumor histology characterized by lymphovascular (P=0.008) and perineural (P=0.006) invasion, and clinical histories of pelvic irradiation (P=0.005), hydronephrosis (P=0.022) and no intravesical chemotherapy (P=0.038). All patients with a high (>70%) percentage of ERβ positivity in tissue with >3-month follow-up developed recurrent disease (P=0.009). Higher ERβ level was predictive of worse recurrence-free and overall survival following cystectomy, after adjustment for tumor stage, and remained significantly associated with recurrence-free survival in the multivariable analysis including tumor stage, nodal stage and lymphovascular invasion. Activation of ERβ in bladder cancer cell lines led to significant increases in proliferation, while pharmacological inhibition with tamoxifen blocked cell growth. Our study supports a role for ERβ in aggressive UCB. Pharmacological targeting of ERβ warrants further investigation as a therapeutic strategy in UCB.

Role of oestrogen receptors in bladder cancer development

Early studies documented the existence of sexual dimorphism in bladder cancer occurrence and progression, with a greater bladder cancer incidence in males than females. However, the progression of bladder cancer after diagnosis is much quicker in females than males. These findings can be explained by the effects of female hormones (predominantly oestrogens) and their binding receptors, including oestrogen receptor 1 (ESR1; also known as ERα), oestrogen receptor 2 (ESR2; also known as ERβ), and GPR30 protein on bladder cancer incidence and progression. Results from studies using various in vitro cell lines and in vivo mouse models demonstrate differential roles of oestrogen receptors in cancer initiation and progression. ERα suppresses bladder cancer initiation and invasion, whereas ERβ promotes bladder cancer initiation and progression. Mechanistic studies suggest that ERα and ERβ exert these effects via modulation of the AKT pathway and DNA replication complex, respectively. Targeting these signalling pathways--for example, with ERα agonists, ERβ antagonists, or selective oestrogen receptor modulators such as 4-[2-phenyl-5,7-bis(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-3-yl]phenol (also known as PHTPP)--could lead to the development of new therapeutic approaches for controlling bladder cancer progression.

Understanding the gender disparity in bladder cancer risk: the impact of sex hormones and liver on bladder susceptibility to carcinogens

It has long been known that bladder cancer (BC) incidence is approximately four-fold higher in men than in women in the United States, and a similar disparity also exists in other countries. The reason for this phenomenon is not known, which impedes progress in BC prevention. However, BC incidence is also significantly higher in male animals than in their female counterparts after treatment with aromatic amines, which are principal human bladder carcinogens. These animal studies and related studies in the context of available human data provide significant insight into what may drive the excessive BC risk in men, which is the focus of this article. The carcinogenicity and biotransformation of bladder carcinogens as well as the impact of sex hormones on these processes are discussed, highlighting the novel concept that the gender disparity in BC risk may result primarily from the interplay of androgen, estrogen, and liver, with the liver functioning via its metabolic enzymes as the main decider of bladder exposure to carcinogens in the urine and the male and female hormones exerting opposing effects on carcinogenesis in the bladder and likely also on liver enzymes handling bladder carcinogens. The findings may facilitate further investigation into the mechanism of gender disparity in BC risk and may also have important implications for BC prevention.

Raloxifene inhibits growth of RT4 urothelial carcinoma cells via estrogen receptor-dependent induction of apoptosis and inhibition of proliferation

Bladder cancer is the fifth most common type of cancer in the USA, with over 70,000 new cases diagnosed each year. Treatment often involves invasive surgical therapies, as chemotherapy alone is often ineffective and associated with high recurrence rates. Identification of estrogen receptor-β (ERβ) in up to 75 % of urinary tumors raises the question of whether this receptor could be targeted to effectively treat bladder cancer. In this study, a panel of five bladder cancer cell lines representing a variety of disease stage and grades were treated with the antiestrogens 4-hydroxytamoxifen, raloxifene, or the pure antagonist ICI 182,780. All cell lines were ERβ positive while only a few expressed estrogen receptor-α (ERα). Notably, all but the TCCSUP cell line were growth inhibited 20-100 % by at least two antiestrogens. Using RT4 cells, we demonstrate that growth inhibition by raloxifene is ER dependent and either ERα or ERβ can mediate this response. Activation of caspase-3 and its effector poly-ADP ribose polymerase (PARP) demonstrate that raloxifene-induced growth inhibition is in part the result of increased apoptosis; this PARP cleavage was ER dependent. Moreover, changes in the expression of cell cycle genes indicate that cell proliferation is also affected. Specifically, raloxifene treatment results in the stabilization of p27 protein, likely via the downregulation of S-phase kinase-associated protein (SKP2). Expression of the negative cell cycle regulator B-cell translocation gene (BTG2) is also increased, while cyclin D1 transcription is reduced. These results indicate that antiestrogens may be useful therapeutics in the treatment of bladder cancer by targeting ER and inhibiting growth via multiple mechanisms.

Estrogen receptor β (ERβ) is a novel prognostic marker of recurrence survival in non-muscle-invasive bladder cancer potentially by inhibiting cadherin switch

OBJECTIVE

The function and significance of estrogen receptor β (ERβ) in bladder cancer remains a field of hot debate. In this study, we aimed to (a) evaluate ERβ as a novel prognostic marker of recurrence-free survival and (b) digest the underlying mechanism by elucidating the relationship between ERβ expression and cadherin switch.

METHODS

We examined the expression levels of ERβ, E-cadherin and N-cadherin in 42 initial non-muscle-invasive urothelial bladder carcinomas via immunohistochemistry. Correlation analysis was performed among ERβ expression, cadherin switch, and recurrence-free survival. Moreover, in vitro studies were performed to validate the identified correlation using two bladder cancer cell lines RT4 and 253 J. Upon stimulation with an ERβ-selective agonist diarylpropionitrile, E-cadherin, N-cadherin expressions; cell migration, and invasion capacity were assessed.

RESULTS

Expression of ERβ protein was seen in 34 bladder cancer cases (80.9%), and 21 (50%) specimens showed non-cadherin switch (positive E-cadherin and negative N-cadherin). ERβ expression and the non-cadherin switch are both accompanied with better recurrence-free survival. Also, the least ERβ expression was observed in specimens that undergo cadherin switch. Moreover, these results were consistent with our observations in bladder cancer RT4 and 253 J cell lines studies. Diarylpropionitrile stimulation resulted in an increase in E-cadherin, a decrease in N-cadherin expressions and abolished cell migration and invasion.

CONCLUSION

ERβ is a prognostic marker of recurrence-free rate in non-muscle-invasive bladder cancer, potentially through suppressing cadherin switch, and may act as a potential target for bladder cancer therapy.

Association between smoking and risk of bladder cancer among men and women

CONTEXT

Previous studies indicate that the population attributable risk (PAR) of bladder cancer for tobacco smoking is 50% to 65% in men and 20% to 30% in women and that current cigarette smoking triples bladder cancer risk relative to never smoking. During the last 30 years, incidence rates have remained stable in the United States in men (123.8 per 100,000 person-years to 142.2 per 100,000 person-years) and women (32.5 per 100,000 person-years to 33.2 per 100,000 person-years); however, changing smoking prevalence and cigarette composition warrant revisiting risk estimates for smoking and bladder cancer.

OBJECTIVE

To evaluate the association between tobacco smoking and bladder cancer.

DESIGN, SETTING, AND PARTICIPANTS

Men (n = 281,394) and women (n = 186,134) of the National Institutes of Health-AARP (NIH-AARP) Diet and Health Study cohort completed a lifestyle questionnaire and were followed up between October 25, 1995, and December 31, 2006. Previous prospective cohort studies of smoking and incident bladder cancer were identified by systematic review and relative risks were estimated from fixed-effects models with heterogeneity assessed by the I(2) statistic.

MAIN OUTCOME MEASURES

Hazard ratios (HRs), PARs, and number needed to harm (NNH).

RESULTS

During 4,518,941 person-years of follow-up, incident bladder cancer occurred in 3896 men (144.0 per 100,000 person-years) and 627 women (34.5 per 100,000 person-years). Former smokers (119.8 per 100,000 person-years; HR, 2.22; 95% confidence interval [CI], 2.03-2.44; NNH, 1250) and current smokers (177.3 per 100,000 person-years; HR, 4.06; 95% CI, 3.66-4.50; NNH, 727) had higher risks of bladder cancer than never smokers (39.8 per 100,000 person-years). In contrast, the summary risk estimate for current smoking in 7 previous studies (initiated between 1963 and 1987) was 2.94 (95% CI, 2.45-3.54; I(2) = 0.0%). The PAR for ever smoking in our study was 0.50 (95% CI, 0.45-0.54) in men and 0.52 (95% CI, 0.45-0.59) in women.

CONCLUSION

Compared with a pooled estimate of US data from cohorts initiated between 1963 and 1987, relative risks for smoking in the more recent NIH-AARP Diet and Health Study cohort were higher, with PARs for women comparable with those for men.