Estrogen exposure and bladder cancer risk in Egyptian women

Unveiling an Association between Waterpipe Smoking and Bladder Cancer Risk: A Multicenter Case-Control Study in Iran

BACKGROUND

Limited data exist for the association between bladder cancers and waterpipe smoking, an emerging global public health concern.

METHODS

We used the IROPICAN database in Iran and used multivariable logistic regression, adjusting for cigarette smoking, opium use, and other confounding factors. In addition, we studied the association between exclusive waterpipe smoking and bladder cancer.

RESULTS

We analyzed 717 cases and 3,477 controls and a subset of 215 patients and 2,145 controls who did not use opium or cigarettes. Although the OR adjusted for opium, cigarettes, and other tobacco products was 0.92 [95% confidence interval (CI), 0.69-1.20], we observed a statistically significant elevated risk in exclusive waterpipe smokers (OR = 1.78; 95% CI, 1.16-2.72) compared with non-users of opium or any tobacco. Associations were strongest for smoking more than two heads/day (OR = 2.25; 95% CI, 1.21-4.18) and for initiating waterpipe smoking at an age less than 20 (OR = 2.73; 95% CI, 1.11-6.72). The OR for urothelial bladder cancer was higher in ex-smokers (OR = 2.35; 95% CI, 1.24-4.42) than in current smokers (OR = 1.52; 95% CI, 0.72-3.15). All observed associations were consistently higher for urothelial histology.

CONCLUSIONS

Waterpipe smoking may be associated with an increased risk of bladder cancer, notably among individuals who are not exposed to cigarette smoking and opium.

IMPACT

The study provides compelling evidence that waterpipe smoking is a confirmed human carcinogen, demanding action from policymakers. See related In the Spotlight, p. 461.

Biological differences underlying sex and gender disparities in bladder cancer: current synopsis and future directions

Sex and gender disparities in bladder cancer have long been a subject of interest to the cancer research community, wherein men have a 4 times higher incidence rate than women, and female patients often present with higher-grade disease and experience worse outcomes. Despite the known differences in disease incidence and clinical outcomes between male and female bladder cancer patients, clinical management remains the same. In this review, we critically analyze studies that report on the biological differences between men and women and evaluate how these differences contribute to sex and gender disparities in bladder cancer. Distinct characteristics of the male and female immune systems, differences in circulating hormone levels and hormone receptor expression, and different genetic and epigenetic alterations are major biological factors that all likely contribute to disparate incidence rates and outcomes for male and female bladder cancer patients. Future preclinical and clinical studies in this area should employ experimental approaches that account for and consider sex and gender disparities in bladder cancer, thereby facilitating the development of precision medicine for the effective treatment of bladder cancer in all patients.

Mechanism of Sex Differences in Bladder Cancer: Evident and Elusive Sex-biasing Factors

Bladder cancer incidence is drastically higher in males than females across geographical, racial, and socioeconomic strata. Despite potential differences in tumor biology, however, male and female bladder cancer patients are still clinically managed in highly similar ways. While sex hormones and sex chromosomes have been shown to promote observed sex differences, a more complex story lies beneath these evident sex-biasing factors than previously appreciated. Advances in genomic technology have spurred numerous preclinical studies characterizing elusive sex-biasing factors such as epigenetics, X chromosome inactivation escape genes, single nucleotide polymorphism, transcription regulation, metabolism, immunity, and many more. Sex-biasing effects, if properly understood, can be leveraged by future efforts in precision medicine based on a patient’s biological sex. In this review, we will highlight key findings from the last half century that demystify the intricate ways in which sex-specific biology contribute to differences in pathogenesis as well as discuss future research directions.

PBX1 Participates in Estrogen-mediated Bladder Cancer Progression and Chemo-resistance Affecting Estrogen Receptors

BACKGROUND

Bladder cancer (BCa) is a common cancer associated with high morbidity and mortality worldwide. Pre-B-cell leukemia transcription factor 1 (PBX1) has been reported to be involved in tumor progression.

OBJECTIVE

The aim of the study was to explore the specific role of PBX1 in BCa and its underlying mechanisms.

METHODS

The relative expressions of PBX1 in muscle-invasive BCa tissues and cell lines were analyzed through RT-qPCR and western blotting. Kaplan-Meier analysis was used to analyze the relationship between PBX1 levels and survival status. Co-immunoprecipitation (CO-IP) and chromatin immunoprecipitation (ChIP)-qPCR assays were adopted to verify the interaction between PBX1 and Estrogen receptors (ERs) and explore the estrogen receptors (ERs)-dependent genes transcription.

RESULTS

PBX1 was upregulated in invasive BCa patients and BCa cells, positively associated with tumor size, lymph node metastasis, distant metastasis and poorer survival status. The overexpression of PBX1 promoted cell growth, invasion, epithelial-mesenchymal transition (EMT) process and cisplatin resistance in BCa cells, while the silence of PBX1 showed opposite effects. Furthermore, PBX1 interacted with ERs and was required for ER function. PBX1 overexpression aggravated the tumorpromoting effect of estrogen on BCa cells, while it partially suppressed the inhibitory effects of ER antagonist AZD9496 on BCa cells.

CONCLUSION

This study revealed that PBX1 participated in estrogen mediated BCa progression and chemo-resistance through binding and activating estrogen receptors. Hence, PBX1 may serve as a potential prognostic and therapeutic target for BCa treatment.

Sex Hormone Receptor Signaling in Bladder Cancer: A Potential Target for Enhancing the Efficacy of Conventional Non-Surgical Therapy

There have been critical problems in the non-surgical treatment for bladder cancer, especially residence to intravesical pharmacotherapy, including BCG immunotherapy, cisplatin-based chemotherapy, and radiotherapy. Recent preclinical and clinical evidence has suggested a vital role of sex steroid hormone-mediated signaling in the progression of urothelial cancer. Moreover, activation of the androgen receptor and estrogen receptor pathways has been implicated in modulating sensitivity to conventional non-surgical therapy for bladder cancer. This may indicate the possibility of anti-androgenic and anti-estrogenic drugs, apart from their direct anti-tumor activity, to function as sensitizers of such conventional treatment. This article summarizes available data suggesting the involvement of sex hormone receptors, such as androgen receptor, estrogen receptor-α, and estrogen receptor-β, in the progression of urothelial cancer, focusing on their modulation for the efficacy of conventional therapy, and discusses their potential of overcoming therapeutic resistance.

Rs-1884444 G/T variant in IL-23 receptor is likely to modify risk of bladder urothelial carcinoma by regulating IL-23/IL-17 inflammatory pathway

Bladder urothelial carcinoma (BUC) is a chronic relapsing urological malignancy, which poses a serious threat to human life. Non-resolving chronic-inflammation at the neoplastic site is associated consistently with inducing tumor-progression and poor patient outcomes. Interleukin 23 receptor (IL-23R) is a key element in T-helper 17 cell-mediated inflammatory process, that plays a critical role in orchestrating tumor-promoting inflammation. Therefore, we hypothesized that potentially functional genetic variant rs1884444 G/T of IL-23R may modify BUC risk. To validate this hypothesis, our findings demonstrated that the rs1884444 G/T variant was significantly associated with a reduced risk of BUC compared to controls observed under allelic (T vs. G) and dominant (GT + TT vs. GG) models (P < 0.05). In addition, the frequency of the T-allele has dropped to very low values in the case of high-grades and invasive-tumors (P < 0.05). Thus, T-allele has emerged as a reliable genetic marker for good prognosis of BUC. In tumorgenesis, the binding-affinity of the receptor seemed to be distorted by the effect of the non-conservative G/T variation, which in turn caused the IL-23/IL-17 pathway to be disabled. This was recognized by low levels of IL-23 and IL-17 in the serum of patients, under the influence of all the tested genetic models (P < 0.01). Results also indicated that the level of the receptor-bearing immune cells could be altered in response to the G/T protective effect. For example, the median counts of T-helper CD4⁺ cells and CD56⁺ natural killers increased significantly in conjunction with the decrease in the median count of CD14⁺ tumor-associated-macrophages under the dominant model. Nevertheless, the causative link between this subtle polymorphism and the immune-surveillance against BUC needs further in-depth investigation. Overall, we concluded that the rs-1884444 G/T variant is highly-associated with a reduction in the BUC risk, which may occur via deregulation of the IL-23/IL-17 pathway.

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.

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.

Association of Combined Estrogen-Progestogen and Progestogen-Only Contraceptives with the Development of Cancer

Combined estrogen-progestogen contraceptives (oral contraceptives or OCs) and progestogen-only contraceptives (POCs) are synthetic steroids that bind to steroid hormone receptors, which are widespread throughout the body. They have a profound effect on cellular physiology. Combined OCs have been classified by the International Agency for Research on Cancer (IARC) as Group 1 carcinogens, but their findings have not been updated recently. In order to update the information and better understand the impact that OCs and POCs have on the risk of development of cancers, a comprehensive literature search was undertaken, focusing on more recently published papers. In agreement with the IARC, the recent literature confirms an increased risk of breast cancer and cervical cancer with the use of OCs. The recent literature also confirms the IARC conclusion that OCs decrease the risk of ovarian and endometrial cancers. However, there is little support from recent studies for the IARC conclusion that OCs decrease the risk of colorectal cancer or increase the risk of liver cancer. For liver cancer, this may be due to the recent studies having been performed in areas where hepatitis is endemic. In one large observational study, POCs also appear to increase the overall risk of developing cancer. OCs and POCs appear to increase the overall risk of cancer when carefully performed studies with the least intrinsic bias are considered.

Summary

OCs have been classified as cancer-causing agents, especially leading to increases in breast cancer and cervical cancer. A review of the recent scientific literature was performed to see whether this still appears to be the case. The recent literature supports the cancer-causing role of OCs especially for breast cancer and cervical cancer. Studies also indicate that progesterone-only contraceptives (such as implants and vaginal rings) also can cause cancer. This is especially true for breast cancer and cervical cancer.

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.

Urinary Bladder Cancer in Egypt: Are There Gender Differences in Its Histopathological Presentation?

We investigated gender differences in the histopathologic presentation of bladder cancer cases in Egypt, where both urothelial cell carcinoma (UC) and squamous cell carcinoma (SCC) types are highly prevalent. We used logistic regression to estimate the unadjusted (OR) and adjusted odds ratio (AOR) and 95% confidence interval (CI) of the associations between gender and different histopathologic and sociodemographic parameters of 2,186 confirmed cases of primary bladder cancer (1,775 males and 411 females; 784 SCC and 1,402 UC). There were no statistically significant gender differences in tumor grade, stage, mucosal ulcer, or inflammatory cystitis, regardless of the cancer type, but men were less likely than women to have undergone cystectomy with pelvic lymphadenectomy. Having Schistosoma haematobium (SH) ova in the bladder tissue was significantly associated with male gender in the fully adjusted model of either SCC (AOR (95% CI) = 2.12 (1.15-3.89)) or UC cases (3.78 (1.89-7.55)). Compared to females, male cases were significantly older at time of diagnosis and smokers. In Egypt, regardless of the type of bladder cancer (SCC or UC), male more than female cases had evidence of SH infection, but not other histopathologic differences, in bladder tissue specimens.

Occupations and the Risk of Bladder Cancer in Yazd Province: A Case-Control Study

Background:

Bladder cancer is the most common cancer of the urinary tract, with known occupational causes. The most effective way to prevent occupational cancers of the urinary tract is to prevent exposure to known carcinogens.

Objective:

To examine the relationship between occupation and the risk of bladder cancer.

Methods:

This case-control study was performed on 200 patients with bladder cancer and 200 healthy individuals in Yazd. Data were collected using a researcher-made questionnaire and based on interviews with patients and controls.

Results:

The mean age of cases and controls were 61.5 (SD 13.6) and 61.5 (13.3) years, respectively. Level of education, type of occupation, family history of bladder cancer in the first-degree relatives, and history of chronic and recurrent urinary tract infection, kidney and bladder stones, and using hair dye, were considered the main predictors for bladder cancer.

Conclusion:

There was a significant difference between cases and controls in terms of type of occupation. The risk of bladder cancer was higher among those working in high-risk occupations—metal working, textile, driving, farming, and construction.

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.

George DM, Loffredo CA, Amr S. Nonoccupational exposure to agricultural work and risk of urinary bladder cancer among Egyptian women

This study examined the associations between nonoccupational exposure to agricultural work, through husband or head of household (H/HH) occupation, and urinary bladder cancer risk among Egyptian women. A total of 1,167 women (388 bladder cases and 779 age- and residence-matched, population-based controls) from a multicenter case-control study were included in the analysis. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were estimated using logistic regression. Among married women, those who reported H/HH to be an agricultural worker were at increased risk for bladder cancer as compared to those with H/HH in other occupations, AOR = 1.54, 95% CI [1.09, 2.18]; among unmarried women the risk was not increased, AOR = 0.77, 95% CI [0.45, 1.32]. Nonoccupational exposure to agricultural work, defined as living with an agricultural worker, increased the risk for bladder cancer among married Egyptian women.

Cancer risk in waterpipe smokers: a meta-analysis

Objectives

To quantify by meta-analysis the relationship between waterpipe smoking and cancer, including cancer of the head and neck, esophagus, stomach, lung and bladder.

Methods

We performed a systematic literature search to identify relevant studies, scored their quality, used fixed and random-effect models to estimate summary relative risks (SRR), evaluated heterogeneity and publication bias.

Results

We retrieved information from 28 published reports. Considering only highquality studies, waterpipe smoking was associated with increased risk of head and neck cancer (SRR 2.97; 95 % CI 2.26–3.90), esophageal cancer (1.84; 1.42–2.38) and lung cancer (2.22; 1.24–3.97), with no evidence of heterogeneity or publication bias. Increased risk was also observed for stomach and bladder cancer but based mainly on poor-quality studies. For colorectum, liver and for all sites combined risk estimates were elevated, but there were insufficient reports to perform a meta-analysis.

Conclusions

Contrary to the perception of the relative safety of waterpipe smoking, this meta-analysis provides quantitative estimates of its association with cancers of the head and neck, esophagus and lung. The scarcity and limited quality of available reports point out the need for larger carefully designed studies in well-defined populations.

Significant association of catechol-O-methyltransferase Val158Met polymorphism with bladder cancer instead of prostate and kidney cancer

BACKGROUND

Urological cancers occur worldwide. Many factors, among which the catechol-O-methyltransferase (COMT) Val158Met polymorphism, are said to be associated with the cancer risk. We conducted a meta-analysis to investigate the association between urological cancer susceptibility and COMT Val158Met in different genetic models.

METHODS

This study was based on material obtained from the PubMed, HuGENet and Embase databases. Four models including dominant (AA + AG vs. GG), recessive (AA vs. AG + GG), codominant (AA vs. AG, AA vs. GG) and per-allele analysis (A vs. G) were applied. Odds ratios (OR) and the corresponding 95% confidence intervals (CI) were used to evaluate the power of the associations.

RESULTS

Fourteen eligible studies comprising 3,285 cases and 3,594 controls were included. Although we could not detect a positive function of the COMT Val158Met polymorphism in urological cancers, the polymorphism might be significantly associated with bladder cancer risk (dominant model [AA + AG vs. GG]: OR = 0.736, 95% CI = 0.586-0.925, I2 = 0.00%; recessive model [AA vs. AG + GG]: OR = 0.822, 95%CI = 0.653-1.035, I2 = 6.30%; codominant model [AA vs. AG]: OR = 0.908, 95% CI = 0.710-1.161, I2 = 0.00%; codominant model [AA vs. GG]: OR = 0.693, 95% CI = 0.524-0.917, I2 = 30.20%; allele analysis [A vs. G]: OR = 0.826, 95%CI = 0.717-0.951, I2 = 30.20%). The same significant associations were not found for kidney cancer and prostate cancer risk in different ethnicities. There also seemed to be no distinct effect of the polymorphism on benign prostatic hyperplasia.

CONCLUSIONS

We suggest that bladder cancer but not prostate cancer and kidney cancer could be significantly associated with the Val158Met polymorphism. Interaction of COMT genetic and related environmental factors for urological cancers should not be ignored in future.

Steroid Hormone Receptor Signals as Prognosticators for Urothelial Tumor

There is a substantial amount of preclinical or clinical evidence suggesting that steroid hormone receptor-mediated signals play a critical role in urothelial tumorigenesis and tumor progression. These receptors include androgen receptor, estrogen receptors, glucocorticoid receptor, progesterone receptor, vitamin D receptor, retinoid receptors, peroxisome proliferator-activated receptors, and others including orphan receptors. In particular, studies using urothelial cancer tissue specimens have demonstrated that elevated or reduced expression of these receptors as well as alterations of their upstream or downstream pathways correlates with patient outcomes. This review summarizes and discusses available data suggesting that steroid hormone receptors and related signals serve as biomarkers for urothelial carcinoma and are able to predict tumor recurrence or progression.

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.

Triple-negative breast cancer risk in women is defined by the defect of estrogen signaling: preventive and therapeutic implications

Epidemiologic studies strongly support that triple-negative breast cancers (TNBCs) may be distinct entities as compared with estrogen receptor (ER)+ tumors, suggesting that the etiologic factors, clinical characteristics, and therapeutic possibilities may vary by molecular subtypes. Many investigations propose that reproductive factors and exogenous hormone use differently or even quite inversely affect the risk of TNBCs and ER+ cancers. Controversies concerning the exact role of even the same risk factor in TNBC development justify that the biological mechanisms behind the initiation of both TNBCs and non-TNBCs are completely obscure. To arrive at a comprehensive understanding of the etiology of different breast cancer subtypes, we should also reconsider our traditional concepts and beliefs regarding cancer risk factors. Malignancies are multicausal, but the disturbance of proper estrogen signaling seems to be a crucial risk factor for the development of mammary cancers. The grade of defect in metabolic and hormonal equilibrium is directly associated with TNBC risk for women during their whole life. Inverse impact of menopausal status or parity on the development of ER+ and ER− breast cancers may not be possible; these controversial results derive from the misinterpretation of percentage-based statistical evaluations. Exogenous or parity-associated excessive estrogen supply is suppressive against breast cancer, though the lower the ER expression of tumors, the weaker the anticancer capacity. In women, the most important preventive strategy against breast cancers – included TNBCs – is the strict control and maintenance of hormonal equilibrium from early adolescence through the whole lifetime, particularly during the periods of great hormonal changes.

Agricultural workers and urinary bladder cancer risk in Egypt

The authors examined the associations between farming and the risk for squamous cell (SCC) or urothelial cell (UC) carcinoma of the urinary bladder among Egyptians. The authors used data from a multicenter case-control study (1,525 male and 315 female cases, and 2,069 male and 547 female age- and residence-matched, population-based controls) to calculate adjusted odds ratios (AORs) and 95% confidence intervals (CIs). Men in farming and who never smoked had increased risk for either SCC or UC (AOR [95% CI]: 4.65 [2.59-8.36] and 6.22 [3.82-10.15], respectively). If they ever smoked, their risks were 2.27 (1.75-2.95) and 1.93 (1.58-2.35), respectively. Women in farmer households were at increased risk for SCC (1.40 [0.93-2.09] and UC [1.25 (0.82-1.89]), although not statistically significant. Occupational and environmental exposures to farming increased the risk for bladder cancer among Egyptians.

Genetic polymorphisms in NQO1 and SOD2: interactions with smoking, schistosoma infection, and bladder cancer risk in Egypt

BACKGROUND

Bladder cancer is the most prevalent form of cancer in men among Egyptians, for whom tobacco smoke exposure and Schistosoma haematobium (SH) infection are the major risk factors. We hypothesized that functional polymorphisms in

NAD(P)H

quinone oxidoreductase 1 (NQO1) and superoxide dismutase 2 (SOD2), modulators of the effects of reactive oxidative species, can influence an individual's susceptibility to these carcinogenic exposures and hence the risk of bladder cancer.

METHODS

We assessed the effects of potential interactions between functional polymorphisms in the NQO1 and SOD2 genes and exposure to smoking and SH infection on bladder cancer risk among 902 cases and 804 population-based controls in Egypt. We used unconditional logistic regression to estimate the odds ratios (OR) and confidence intervals (CI) 95%.

RESULTS

Water pipe and cigarette smoking were more strongly associated with cancer risk among individuals with the TT genotype for SOD2 (OR [CI 95%] = 4.41 [1.86-10.42]) as compared with those with the CC genotype (OR [CI 95%] = 2.26 [0.97-6.74]). Conversely, the risk associated with SH infection was higher among the latter (OR [CI 95%] = 3.59 [2.21-5.84]) than among the former (OR [CI 95%] = 1.86 [1.33-2.60]). Polymorphisms in NQO1 genotype showed a similar pattern, but to a much lesser extent. The highest odds for having bladder cancer following SH infection were observed among individuals with the CC genotypes for both NQO1 and SOD2 (OR [CI 95%] = 4.41 [2.32-8.38]).

CONCLUSION

Our findings suggest that genetic polymorphisms in NQO1 and SOD2 play important roles in the etiology of bladder cancer by modulating the effects of known contributing factors such as smoking and SH infection.

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.

Circulatory estrogen level protects against breast cancer in obese women

Literary data suggest apparently ambiguous interaction between menopausal status and obesity-associated breast cancer risk based on the principle of the carcinogenic capacity of estrogen. Before menopause, breast cancer incidence is relatively low and adiposity is erroneously regarded as a protective factor against this tumor conferred by the obesity associated defective estrogen-synthesis. By contrast, in postmenopausal cases, obesity presents a strong risk factor for breast cancer being mistakenly attributed to the presumed excessive estrogen-production of their adipose-tissue mass. Obesity is associated with dysmetabolism and endangers the healthy equilibrium of sexual hormone-production and regular menstrual cycles in women, which are the prerequisites not only for reproductive capacity but also for somatic health. At the same time, literary data support that anovulatory infertility is a very strong risk for breast cancer in young women either with or without obesity. In the majority of premenopausal women, obesity associated insulin resistance is moderate and may be counteracted by their preserved circulatory estrogen level. Consequently, it is not obesity but rather the still sufficient estrogen-level, which may be protective against breast cancer in young adult females. In obese older women, never using hormone replacement therapy (HRT) the breast cancer risk is high, which is associated with their continuous estrogen loss and increasing insulin-resistance. By contrast, obese postmenopausal women using HRT, have a decreased risk for breast cancer as the protective effect of estrogen-substitution may counteract to their obesity associated systemic alterations. The revealed inverse correlation between circulatory estrogen-level and breast cancer risk in obese women should advance our understanding of breast cancer etiology and promotes primary prevention measures. New patents recommend various methods for the prevention and treatment of obesity-related systemic disorders and the associated breast cancer.

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.

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.

[Interactions of insulin and estrogen in the regulation of cell proliferation and carcinogenesis]

Equilibrium of sexual steroids and metabolic processes has close correlations. Insulin is a potent regulator of human sexual steroid hormone production and modulates their signals at receptor level. Insulin resistance and excessive insulin production provoke hyperandrogenism and estrogen deficiency in women resulting not only in anovulatory dysfunction but also a high risk for cardiovascular diseases and cancer. Physiologic functions of all female organs have higher estrogen demand as compared with men. In healthy women estrogen predominance against androgens is a favor in their reproductive period, which means a strong defense against insulin resistance and its complications. However, in postmenopausal cases the increasing prevalence of insulin resistance and type-2 diabetes associated with estrogen deficiency and androgen excess, result in a gender specific higher risk for precancerous lesions and cancer as compared with men. Estrogen has beneficial effect on the energy metabolism, glucose homeostasis and on the lipid metabolism of liver and of peripheral tissues as well. A moderate or severe decrease in serum estrogen level enhances the prevalence of insulin resistant states. In premenopausal women long or irregular menstrual cycles are predictors for the risk of insulin resistance and type-2 diabetes. Moreover, in postmenopausal estrogen deficient cases elevated fasting glucose, increased body weight and abdominal fat deposition are often observed progressively with age in correlation with an impaired glucose tolerance. In the rare cases of estrogen deficient men severe type-2 diabetes seems to be a characteristic complication. Upon becoming familiar with the cancer risk of insulin resistance and estrogen deficiency, there would be plenty of possibilities for primary cancer prevention. In patients with cancer the treatment of hormonal and metabolic disturbances may become effective adjuvant therapy.

Interplay between insulin resistance and estrogen deficiency as co- activators in carcinogenesis

Both insulin resistance and estrogen deficiency result in complex metabolic disorder based mainly on defective cellular glucose uptake and on an atherogenic serum lipid profile. These alterations may be regarded as high risks for several life-threatening human diseases, such as type-2 diabetes, cardiovascular lesions and malignancies. Insulin resistance and estrogen deficiency are concomitant disorders with mutual interrelationship. Insulin resistance and the compensatory hyperinsulinemia provoke increased androgen synthesis at the expense of decreased estrogen production. Similarly, a moderate or severe decrease in serum estrogen levels enhances the prevalence of insulin resistant states both in men and women. Healthy premenopausal women enjoy the defensive effect of estrogens against metabolic and hormonal disorders. However, even a slight decrease in their circulatory estrogen levels associated with insulin resistance may increase the risk for cancers, particularly in the organs having high estrogen demand (breast, endometrium and ovary). On the other hand, postmenopausal state with profound estrogen deficiency confers high risk for cancers in different organs with either high or moderate estrogen demand. After menopause, hormone replacement therapy improves insulin sensitivity and decreases the enhanced inclination to malignancies in postmenopausal women. Recognition of the thorough interplay between insulin resistance and estrogen deficiency may illuminate many apparently controversial experimental and clinical findings concerning cancer development and therapeutic possibilities. Moreover, their interactions in the initiation and progression of human malignancies may supply new strategies in primary cancer prevention and cancer cure.

GSTM1, GSTT1 null variants, and GPX1 single nucleotide polymorphism are not associated with bladder cancer risk in Egypt

BACKGROUND

Bladder cancer is the most common male malignancy in Egypt, consists predominantly of urothelial cell carcinoma (UCC) and squamous cell carcinoma (SCC), and disparities in incidence exist between men and women regardless of geographic region. Tobacco smoke exposure and Schistosoma haematobium (SH) infection and the presence of GSTM1, GSTT1, and GPX1 genotypes, as modulators of the carcinogenic effect of reactive oxidative species, were hypothesized to modify bladder cancer risk and possibly explain these gender differences.

METHODS

We evaluated the association between bladder cancer risk and functional polymorphisms in the GSTM1, GSTT1, and GPX1 genes in 625 cases and 626 matched population-based controls in Egypt and assessed for potential interactions between these candidate genes and environmental exposures, such as smoking and SH infection. We analyzed the risk for developing UCC and SCC separately.

RESULTS

None of these functional polymorphisms were significantly associated with bladder cancer risk. There were no significant interactions between genotypes and smoking or SH infection in this population, nor was any difference detected in genotypic risk between men and women.

CONCLUSIONS

Our findings suggest that common genetic variations in GSTM1, GSTT1, and GPX1 are not associated with bladder cancer risk overall and that well-known environmental risk factors, such as smoking and SH infection, do not interact with these genes to modulate the risk.

IMPACT

Our data indicate that common genetic variations in GSTM1, GSTT1, and GPX1 were not associated with bladder cancer risk.

Associations differ by sex for catechol-O-methyltransferase genotypes and bladder cancer risk in South Egypt

OBJECTIVES

To examine associations between urinary bladder cancer risk and polymorphisms of the gene encoding the catechol estrogen-metabolizing enzyme, catechol-O-methyltransferase (COMT), among Egyptian women and men.

MATERIALS AND METHODS

We used questionnaire and genotype data from a case-control study in Egypt. This analysis focused on South Egypt cases with confirmed urothelial (UC) or squamous cell (SCC) carcinoma of the bladder, and controls frequency-matched on sex, 5-year age-group, and residence governorate. Real-time PCR on blood specimen DNA was used to determine COMT genotypes encoding for Val/Val, Val/Met, and Met/Met, the enzyme forms associated with high, intermediate, or low activity, respectively.

RESULTS

The study sample, which included 255 women and 666 men, consisted of 394 cases with histologically confirmed UC (225) or SCC (n = 169), and 527 controls. The odds of having either type of bladder cancer were lower among men with genotypes encoding Val/Met or Met/Met than among those with the genotype encoding Val/Val, even after adjustment for other factors, such as smoking and schistosomiasis history [adjusted odds ratio (AOR): 0.64; 95% confidence interval (CI): 0.43, 0.96]; however, the association was statistically significant for SCC (AOR 0.57; 95% CI: 0.34, 0.96) but marginal for UC (AOR: 0.64; 95% CI: 0.39, 1.02). No significant associations were detected between bladder cancer risk and COMT genotypes among postmenopausal women.

CONCLUSIONS

These findings suggest that even after controlling for established risk factors, the involvement of COMT genotypes in bladder cancer risk differs among men compared with women in South Egypt.