Bisphenol A induce ovarian cancer cell migration via the MAPK and PI3K/Akt signalling pathways

Endocrine disrupting chemicals in Italian drinking water systems: Insights from a three-year investigation combining chemical and effect-based tools

Drinking water quality can be compromised by endocrine-disrupting chemicals (EDCs). Three phenolic compounds [bisphenol A (BPA), nonylphenol (NP), and 4-octylphenol (OP)] and three hormones [17β-estradiol (E2), estrone (E1), and 17α-ethinylestradiol (EE2)] were analyzed as EDCs potentially occurring in source and drinking water from three full-scale drinking water treatment plants (DWTPs) in the Romagna area (Italy) by a combined approach of HPLC-MS/MS target analysis and effect-based tests for estrogenicity and genotoxicity. The EDC removal efficiency was evaluated at different steps along the treatment process in the most advanced DWTP. NP prevailed in all samples, followed by BPA. Sporadic contamination by OP and E1/E2 appeared only in the source waters; EE2 was never detected. No estrogenic or genotoxic activity was found, except for two samples showing estrogenicity well below the effect-based trigger value suggested for drinking water safety (0.9 ng/L EEQ). BPA and NP levels were largely below the threshold value; however, increases were observed after the intermediate steps of the treatment chain. The good quality of the water relied on the last step, i.e. the activated carbon filtration. DWTPs may represent an extra source of EDCs and monitoring chemical occurrence at all steps of the process is advisable to improve efficiency.

Bisphenol A regulates bladder cells responses via control of G2/M-phase cell cycle, apoptotic signaling, MAPK pathway, and transcription factor-associated MMP modulation

Bisphenol A (BPA), an exogenous endocrine-disrupting chemical, is widely used to produce polycarbonate plastics. The widely used BPA has been detected in human urine samples, raising public anxiety about the detrimental effects of BPA on the bladder. In this study, we explored regulatory mechanisms for the adverse effects of BPA in human bladder BdFC and T24 cells. BPA induced extrinsic and intrinsic apoptosis and G2/M cell cycle arrest caused by the ATM-CHK1/CHK2-CDC25c-CDC2 signaling, which ultimately inhibited the growth of human bladder cells. We also found that BPA decreased the binding activity of AP-1 and NF-κB transcription factors in human bladder cells, which inhibited migration and invasion through matrix metallopeptidase-2 and -9 inactivation. Phosphorylation of MAPKs was implicated with BPA-mediated detrimental effects in human bladder cells. Collectively, our results provide a novel explanation for the underlying molecular mechanisms that BPA induces cytotoxicity in human bladder cells.

Expression Profiles of Genes Related to Development and Progression of Endometriosis and Their Association with Paraben and Benzophenone Exposure

Increasing evidence has been published over recent years on the implication of endocrine-disrupting chemicals (EDCs), including parabens and benzophenones in the pathogenesis and pathophysiology of endometriosis. However, to the best of our knowledge, no study has been published on the ways in which exposure to EDCs might affect cell-signaling pathways related to endometriosis. We aimed to describe the endometriotic tissue expression profile of a panel of 23 genes related to crucial cell-signaling pathways for the development and progression of endometriosis (cell adhesion, invasion/migration, inflammation, angiogenesis, and cell proliferation/hormone stimulation) and explore its relationship with the exposure of patients to parabens (PBs) and benzophenones (BPs). This cross-sectional study included a subsample of 33 women with endometriosis from the EndEA study, measuring their endometriotic tissue expressions of 23 genes, while urinary concentrations of methyl-, ethyl-, propyl-, butyl-paraben, benzophenone-1, benzophenone-3, and 4-hydroxybenzophenone were determined in 22 women. Spearman's correlations test and linear and logistic regression analyses were performed. The expression of 52.2% of studied genes was observed in >75% of endometriotic tissue samples and the expression of 17.4% (n = 4) of them in 50-75%. Exposure to certain PB and BP congeners was positively associated with the expression of key genes for the development and proliferation of endometriosis. Genes related to the development and progression of endometriosis were expressed in most endometriotic tissue samples studied, suggesting that exposure of women to PBs and BPs may be associated with the altered expression profile of genes related to cellular pathways involved in the development of endometriosis.

Alterations induced by Bisphenol A on cellular organelles and potential relevance on human health

Bisphenol A (BPA) is a chemical partially soluble in water and exists in a solid state. Its structural similarity with estrogen makes it an endocrine-disrupting chemical. BPA can disrupt signaling pathways at very low doses and may cause organellar stress. According to in vitro and in vivo studies, BPA interacts with various cell surface receptors to cause organellar stress, producing free radicals, cellular toxicity, structural changes, DNA damage, mitochondrial dysfunction, cytoskeleton remodeling, centriole duplication, and aberrant changes in several cell signaling pathways. The current review summarizes the impact of BPA exposure on the structural and functional aspects of subcellular components of cells such as the nucleus, mitochondria, endoplasmic reticulum, lysosome, ribosome, Golgi apparatus, and microtubules and its consequent impact on human health.

Exploratory profiles of phenols, parabens, and per- and poly-fluoroalkyl substances among NHANES study participants in association with previous cancer diagnoses

BACKGROUND

Some hormonally active cancers have low survival rates, but a large proportion of their incidence remains unexplained. Endocrine disrupting chemicals may affect hormone pathways in the pathology of these cancers.

OBJECTIVE

To evaluate cross-sectional associations between per- and polyfluoroalkyl substances (PFAS), phenols, and parabens and self-reported previous cancer diagnoses in the National Health and Nutrition Examination Survey (NHANES).

METHODS

We extracted concentrations of 7 PFAS and 12 phenols/parabens and self-reported diagnoses of melanoma and cancers of the thyroid, breast, ovary, uterus, and prostate in men and women (≥20 years). Associations between previous cancer diagnoses and an interquartile range increase in exposure biomarkers were evaluated using logistic regression models adjusted for key covariates. We conceptualized race as social construct proxy of structural social factors and examined associations in non-Hispanic Black, Mexican American, and other Hispanic participants separately compared to White participants.

RESULTS

Previous melanoma in women was associated with higher PFDE (OR:2.07, 95% CI: 1.25, 3.43), PFNA (OR:1.72, 95% CI: 1.09, 2.73), PFUA (OR:1.76, 95% CI: 1.07, 2.89), BP3 (OR: 1.81, 95% CI: 1.10, 2.96), DCP25 (OR: 2.41, 95% CI: 1.22, 4.76), and DCP24 (OR: 1.85, 95% CI: 1.05, 3.26). Previous ovarian cancer was associated with higher DCP25 (OR: 2.80, 95% CI: 1.08, 7.27), BPA (OR: 1.93, 95% CI: 1.11, 3.35) and BP3 (OR: 1.76, 95% CI: 1.00, 3.09). Previous uterine cancer was associated with increased PFNA (OR: 1.55, 95% CI: 1.03, 2.34), while higher ethyl paraben was inversely associated (OR: 0.31, 95% CI: 0.12, 0.85). Various PFAS were associated with previous ovarian and uterine cancers in White women, while MPAH or BPF was associated with previous breast cancer among non-White women.

IMPACT STATEMENT

Biomarkers across all exposure categories (phenols, parabens, and per- and poly- fluoroalkyl substances) were cross-sectionally associated with increased odds of previous melanoma diagnoses in women, and increased odds of previous ovarian cancer was associated with several phenols and parabens. Some associations differed by racial group, which is particularly impactful given the established racial disparities in distributions of exposure to these chemicals. This is the first epidemiological study to investigate exposure to phenols in relation to previous cancer diagnoses, and the first NHANES study to explore racial/ethnic disparities in associations between environmental phenol, paraben, and PFAS exposures and historical cancer diagnosis.

Environmental-relevant bisphenol A exposure promotes ovarian cancer stemness by regulating microRNA biogenesis

Bisphenol A (BPA) is a ubiquitous environmental xenobiotic impacting millions of people worldwide. BPA has long been proposed to promote ovarian carcinogenesis, but the detrimental mechanistic target remains unclear. Cancer stem cells (CSCs) are considered as the trigger of tumour initiation and progression. Here, we show for the first time that nanomolar (environmentally relevant) concentration of BPA can markedly increase the formation and expansion of ovarian CSCs concomitant. This effect is observed in both oestrogen receptor (ER)-positive and ER-defective ovarian cancer cells, suggesting that is independent of the classical ERs. Rather, the signal is mediated through alternative ER G-protein-coupled receptor 30 (GPR30), but not oestrogen-related receptor α and γ. Moreover, we report a novel role of BPA in the regulation of Exportin-5 that led to dysregulation of microRNA biogenesis through miR-21. The use of GPR30 siRNA or antagonist to inhibit GPR30 expression or activity, respectively, resulted in significant inhibition of ovarian CSCs. Similarly, the CSCs phenotype can be reversed by expression of Exportin-5 siRNA. These results identify for the first time non-classical ER and microRNA dysregulation as novel mediators of low, physiological levels of BPA function in CSCs that may underlie its significant tumour-promoting properties in ovarian cancer.

BPA exposure enhances the metastatic aggression of ovarian cancer through the ERα/AKT/mTOR/HIF-1α signaling axis

Long-term exposure to bisphenol A (BPA) in humans may promote ovarian cancer development. In present study, the mechanisms by which BPA mediates the aggression metastatic behavior of ovarian cancer were investigated in vitro/in vivo. The results showed that BPA (10 μM) significantly promoted the proliferation, migration and invasion of human ovarian cancer cells (ES-2 and OVCAR-3 cells); moreover, it promoted ES-2 and OVCAR-3 cell glucose uptake, lactic acid release and intracellular ATP synthesis. After administration of 5 μg/kg/day BPA, tumor volume was increased compared with that in control group. KEGG and GO enrichment analyses showed that the genes from ES-2 cell in 10 μM BPA-treated group were enriched mainly in central carbon metabolism and PI3K-AKT signaling pathway. Then, qRT‒PCR and western blotting results showed that BPA (10 μM) increased the mRNA and protein expression levels of glycolysis-related genes and mTOR, p-AKT HIF-1α and ERα in vitro/vivo; whereas this effect was reduced after treatment with the ERα inhibitor methyl-piperidino-pyrazole. Furthermore, coimmunoprecipitation and mass spectrometry showed that BPA promoted the direct interaction of ERα with lactate dehydrogenase A. These results show that BPA directly promoted the proliferation, migration and invasion of ovarian cancer cells through the ERα/AKT/mTOR/HIF-1α signaling axis to enhance glycolysis.

Bisphenols S and F drive ovarian granulosa cell tumor invasion via a metabolic switch

Alterations in the metabolism of cancer cells are crucial for tumor growth and progression. However, the mechanism whereby environmental pollutants such as bisphenols F (BPF) and S (BPS) affect glucose metabolism through the glycolytic pathway, and therefore influence tumor progression, are unclear. Both bisphenols are endocrine-disrupting molecules that are used in plastics. As a consequence of their widespread use, these compounds have been detected in various human body fluids. Thus, hormone-sensitive cancers, such as ovarian cancers, are exposed to these compounds. In the present study, we aimed to determine the effects of the concentrations of BPS and BPF found in body fluids on the cell viability, glucose uptake, glycolysis, oxygen consumption, and invasion by the adult ovarian granulosa cell tumor (AGCT) cell line. We found that BPS and BPF increased the glucose uptake, hexokinase activity, proliferation, and invasion of the cells at environmentally relevant concentrations. Furthermore, we identified an inhibition of glycolysis in parallel with an increase in oxygen consumption, suggesting a BPS/BPF-induced switch from aerobic glycolysis to mitochondrial respiration. In summary, these findings demonstrate a new mechanism through which BPS and BPF promote ovarian granulosa cell tumor progression by increasing energy production through mitochondrial respiration. Thus, both bisphenols induced a metabolic switch that appears to be a stimulus for AGCT progression.

Metastatic effects of environmental carcinogens mediated by MAPK and UPR pathways with an in vivo Drosophila Model

Metastasis includes tumor invasion and migration and underlies over 90% of cancer mortality. The metastatic effects of environmental carcinogens raised serious health concerns. However, the underlying mechanisms remained poorly studied. In the present study, an in vivo Ras^V12/lgl^-/- model of the fruitfly, Drosophila melanogaster, with an 8-day exposure was employed to explore the metastatic effects of 3,3',4,4',5-pentachlorobiphenyl (PCB126), perfluorooctanoic acid (PFOA) and cadmium chloride (CdCl₂). At 1.0 mg/L, PCB126, PFOA, and CdCl₂ significantly increased tumor invasion rates by 1.32-, 1.33-, and 1.29-fold of the control, respectively. They also decreased the larval body weight and locomotion behavior. Moreover, they commonly disturbed the expression levels of target genes in MAPK and UPR pathways, and their metastatic effects were significantly abolished by the addition of p38 inhibitor (SB203580), JNK inhibitor (SP600125) and IRE1 inhibitor (KIRA6). Notably, the addition of the IRE inhibitor significantly influenced sna/E-cad pathway which is essential in both p38 and JNK regulations. The results demonstrated an essential role of sna/E-cad in connecting the effects of carcinogens on UPR and MAPK regulations and the resultant metastasis.

Contribution of common plastic-related endocrine disruptors to epithelial-mesenchymal transition (EMT) and tumor progression

Many chemicals, including many endocrine disruptors (EDCs) are known to leach out from various plastic consumer products and waste, and are widespread in the environment. EDCs are a large group of contaminants that can interfere with hormonal metabolism or function. In addition, there are in the literature implications of contribution by EDCs in tumor progression, the last stage of carcinogenesis driven by cells with a metastatic phenotype. The process of epithelial cells losing their apical-basal polarity and cell-to-cell contacts, and acquiring migration and invasive properties typical of mesenchymal cells is called epithelial-mesenchymal transition (EMT). It is essential for tumor progression. In human cells, plastic-related EDCs, (phthalates, bisphenol A, and the alkylphenols: nonylphenol and octylphenol) reduce epithelial E-cadherin, and increase mesenchymal N-cadherin and extracellular matrix metalloproteinases. These changes are hallmarks of EMT. In xenograft mouse studies, EDCs increase migration of cells and metastatic growth in distant tissues. Their contribution to EMT and tumor progression, the topic of this review, is important from public health perspective, because of the ubiquitous exposure to these EDCs. In this mini-review we also discuss molecular mechanisms associated with EDC-induced EMT and tumor progression.

A high-throughput screening assay for identification of chemicals with liver tumor promoting potential using a transgenic zebrafish line

Traditional high-throughput methods for identification of chemicals with liver tumor promotion potentials are based on established cancer cell lines, and rapid and cost-effective high-throughput screening assays in whole organisms are presently lacking. In this study, a transgenic zebrafish liver cancer model was employed to develop a method that could be used to identify chemicals with liver tumor promotion effect quickly and accurately. The method consisted of three parts, including exposure preparation, exposure process and image acquisition. In brief, after chemical exposure for 7 days, 96-well plate exposure system for zebrafish larvae was assessed by microplate reader. Then, the liver cancer promoting potential chemicals were evaluated by field area and field average intensity of fluorescence. The results were further validated by conducting histopathological examination. Our data demonstrated that the high-throughput screening assay developed in this study was reproducible and could be used to rapidly screen chemicals with liver tumor promoting potentials by using tris-(2-chloropropyl)-phosphate (TDCIPP) as a positive control. Furthermore, some other positive chemicals found in previous studies and environmental compounds were assessed using the established method. Results indicated that 86.7% of the positive chemicals and five environmental compounds out of seventeen compounds could enhance liver tumor progression.

Integration of data from the cell-based ERK1/2 ELISA and the Comparative Toxicogenomics Database deciphers the potential mode of action of bisphenol A and benzo[a]pyrene in lung neoplasm

Chemicals can activate a variety of signaling pathways, initiating changes in gene expression and cellular functions. Here, we combined experimental data on the chemical-induced extracellular signal-regulated kinase 1/2 (ERK1/2) activation with the Comparative Toxicogenomics Database (CTD) to connect signaling, genes, and phenotypes to reveal the potential chemical's mode of action (MOA) responsible for the disease state. Experimental data on ERK1/2 activation were derived from the cell-based phospho-ERK1/2 ELISA on human alveolar epithelial cells A549. A549 cells were exposed to bisphenol A (BPA), benzo[a]pyrene (BaP), tributyltin (TBT), and ibuprofen from 10^-12 M to 10^-5 M. Results show that BPA, BaP, and TBT can activate ERK1/2 in A549 cells. We selected BPA and BaP to elucidate the molecular events connecting chemical exposure, ERK1/2 signaling, phenotypes, and lung neoplasm (LN) using CTD. CTD analysis showed that BPA and BaP share 26 mitogen-activated protein kinase 1/3 (MAPK1/3) signaling genes associated with LN. Phenotype prioritization revealed 37 BPA, 10 BaP, and 11 shared key phenotypes associated with LN. Alignment of MAPK1/3 signaling genes and phenotypes showed that ERK1/2 and oxidative stress, EGFR gene, and positive regulation of cell proliferation and migration could be the shared key events (KE) for BPA and BaP. This analysis also identified protein kinase B and ERK1/2 signaling, FGF9, FGFR1 and FGFR2 genes, positive regulation of cell proliferation and angiogenesis as KE in MOA for BPA, whereas ERK1/2 signaling, IL6 and DAB2IP genes, negative regulation of cell proliferation and inflammatory response were identified as KE in MOA for BaP.

Research progress on the association between environmental pollutants and the resistance mechanism of PARP inhibitors in ovarian cancer

The occurrence and progression of ovarian cancer are closely related to genetics and environmental pollutants. Poly(ADP-ribose) polymerase (PARP) inhibitors have been a major breakthrough in the history of ovarian cancer treatment. PARP is an enzyme responsible for post-translational modification of proteins and repair of single-stranded DNA damage. PARP inhibitors can selectively inhibit PARP function, resulting in a synthetic lethal effect on tumor cells defective in homologous recombination repair. However, with large-scale application, drug resistance also inevitably appears. For PARP inhibitors, the diversity and complexity of drug resistance mechanisms have always been difficult problems in clinical treatment. Herein, we mainly summarized the research progress of DNA damage repair and drug resistance mechanisms related to PARP inhibitors and the impact of environmental pollutants on DNA damage repair to aid the development prospects and highlight urgent problems to be solved.

Bisphenol A-induced DNA damages promote to lymphoma progression in human lymphoblastoid cells through aberrant CTNNB1 signaling pathway

Lymphoma is a group of blood cancers that develop from the immune system, and one of the main risk factors is associated with exposure to environmental chemicals. Bisphenol A (BPA) is a common chemical used in the manufacture of materials in polycarbonate and epoxy plastic products and can interfere with the immune system. BPA is considered to possibly induce lymphoma development by affecting the immune system, but its potential mechanisms have not been well established. This study performed a gene-network analysis of microarray data sets in human lymphoma tissues as well as in human cells with BPA exposure to explore module genes and construct the potential pathway for lymphomagenesis in response to BPA. This study provided evidence that BPA exposure resulted in disrupted cell cycle and DNA damage by activating CTNNB1, the initiator of the aberrant constructed CTNNB1-NFKB1-AR-IGF1-TWIST1 pathway, which may potentially lead to lymphomagenesis.

Comparing effects and action mechanisms of BPA and BPS on HTR-8/SVneo placental cells

Bisphenol A (BPA) is one of the most investigated compound as a suspected endocrine disrupting chemical. It has been found at nM concentrations in the maternal serum, cord serum, and amniotic fluid and also permeates placental tissues. Attempts are being made to replace BPA with the analog Bisphenol S (BPS). Also BPS was found in maternal and umbilical cord serum, and urine samples from a large population of pregnant women. A few studies investigated BPA impact on the placentation process, and even less are available for BPS. This work aimed to elucidate and compare the effects of BPA and BPS on physiological functions of HTR-8/SVneo cells, derived from extravillous trophoblast of first-trimester pregnancy. Proliferation and migration ability of trophoblast cells were assessed in vitro after exposure to BPA or BPS (10-13 - 10-3 M). Further, induction of the inflammatory response by the bisphenols was studied. To provide insight into the molecular pathways implicated in the responses, experiments were carried out in the presence or absence of tamoxifen as estrogen receptors (ERs) blocker, and U0126 as ERK1/2 phosphorylation inhibitor. Data indicate that BPA significantly affects both proliferation and migration of HTR-8/SVneo cells, through ER and ERK1/2 mediated processes. Differently, BPS only acts on proliferation, again through ER and ERK1/2 mediated processes. BPS, but not BPA, induces secretion of interleukins 6 and 8. Such effect is inhibited by blocking ERK1/2 phosphorylation. To the best of our knowledge, these are the first data showing that BPS affects trophoblast functions through ER/MAPK modulation.

Inflammatory cytokines as key players of apoptosis induced by environmental estrogens in the ovary

Natural and synthetic environmental estrogens (EEs), interfering with the physiological functions of the body's estrogens, are widespread and are rising much concern for their possible deleterious effects on human and animal health, in particular on reproduction. In fact, increasing evidence indicate that EEs can be responsible for a variety of disfunctions of the reproductive system especially in females such as premature ovarian insufficiency (POI). Because of their great structural diversity, the modes of action of EEs are controversial. One important way through which EEs exert their effects on reproduction is the induction of apoptosis in the ovary. In general, EEs can exert pro-and anti-apoptotic effects by agonizing or antagonizing numerous estrogen-dependent signaling pathways. In the present work, results concerning apoptotic pathways and diseases induced by representative EEs (such as zearalenone, bisphenol A and di-2-ethylhexyl phthalate), in ovaries throughout development are presented into an integrated network. By reviewing and elaborating these studies, we propose inflammatory factors, centered on the production of tumor necrosis factor (TNF), as a major cause of the induction of apoptosis by EEs in the mammalian ovary. As a consequence, potential strategies to prevent such EE effect are suggested.

Bisphenol A induces ovarian cancer cell proliferation and metastasis through estrogen receptor-α pathways

Bisphenol A (BPA) is a widely used raw material that can be detected both in the environment and in the human body. Due to its estrogen-like effects, wide concerns have been raised about the potential role of BPA in the initiation and development of hormone-dependent cancers. Ovarian cancer is the most common reproductive system cancer and has a high mortality rate in women. Despite recent investigations into BPA's carcinogenic effects, studies on its role in ovarian cancer development remain limited. In this study, we aimed to assess the effect of BPA at various environmentally relevant concentrations on proliferation and metastasis of ovarian cancer cells. We discovered that BPA can stimulate proliferation of OVCAR-3 ovarian cancer cells after exposure for up to 5 days. Strikingly, BPA enhanced ovarian cancer cell migration, invasion, and adhesion (to vascular endothelial cells) through upregulation of matrix metalloproteinase-2 (MMP-2), MMP-9, and intercellular cell adhesion molecule-1 (IMAC-1). The stimulatory effects of BPA on cancer cell proliferation and metastasis were reversed by treatment with an ERα inhibitor, but not by treatment with an ERβ inhibitor. Together, these results suggest that BPA induces proliferation and metastasis of ovarian cancer cells through ERα signaling pathways. This study provides new insights into the carcinogenic effects of BPA with regard to ovarian cancer.

Bisphenol analogs AF and S: Effects on cell status and production of angiogenesis-related factors by COV434 human granulosa cell line

While Bisphenol A (BPA) has been a requisite plastic additive, as an endocrine disruptor it has been associated with adverse health effects including ovarian disorders. Following implemented restrictions on BPA usage, it is replaced by alternative bisphenols, biological effects of which have not been adequately investigated. Our study examined effects of bisphenols AF (BPAF) and S (BPS), on the human ovarian granulosa cell line COV434, and compared them with BPA, with the focus on cell viability (10^-9-10^-4 M) and angiogenesis-related factors (10^-9-10^-5 M), relevant for both the follicle development and ovarian pathologies: vascular endothelial growth factor A (VEGF-A), platelet-derived growth factor AA (PDGF-AA), and matrix metalloproteinase 9 (MMP-9). Each bisphenol impaired cell viability and increased generation of intracellular reactive oxygen species at the highest concentration (10^-4 M). While VEGF-A production in BPAF-treated groups did not differ from the control, all doses of BPS and BPA caused a marked reduction in VEGF-A output. Nevertheless, the alterations in VEGF-A production were not caused by the impact on VEGFA gene expression since there were no indications of VEGFA downregulation in the presence of either BPS or BPA. Interestingly, we observed a similar pattern of PDGF-AA output reduction in BPS- and BPA-treated groups to that of VEGF-A production. BPAF and BPS (10^-5 M) increased MMP9 expression, however, this effect was not reflected by the increase in MMP-9 production. The results obtained demonstrate that the novel bisphenol analogs are not inert with respect to the ovarian cells, and their effects might contribute to dysregulation of granulosa cells functions.

Modulation of folliculogenesis in adult laying chickens by bisphenol A and bisphenol S: Perspectives on ovarian morphology and gene expression

Both bisphenol A (BPA) and its analog bisphenol S (BPS) are industrial chemicals that have been used to make certain plastic products applied in chicken farms, including food and water containers. They are endocrine disrupting chemicals (EDCs) with xenoestrogenic activities and affect reproductive success in many ways. It was hypothesized that BPA and BPS could adversely affect the folliculogenesis in chickens due to their disruption of the estrogen responses, using either genomic or non-genomic mechanisms. This study investigated the deleterious effects of BPA and BPS on the ovaries when adult layer chickens were orally treated with these EDCs at 50 μg/kg body weight, the reference dose for chronic oral exposure of BPA established by the U.S. EPA. The chickens in both BPA and BPS-treated groups showed a decreased number of the preovulatory follicles. BPA-treated chickens showed a significant decrease in the diameter of F1. Additionally, both BPA and BPS treatments increased the infiltrations of lymphocytes and plasma cells in ovaries. Moreover, it was found that the ovaries of BPS-treated chickens weighed the most among the groups. RNA sequencing and subsequent pathway enrichment analysis of differentially expressed genes revealed that both BPA- and BPS-treatment groups showed significant changes in gene expression and pathways related to reproduction, immune function and carcinogenesis. Taken together, both BPA and BPS are potentially carcinogenic and have deleterious effects on the fertility of laying chickens by inducing inflammation, suggesting that BPS may not be a safe replacement for BPA.

Combined effect of fulvestrant and low dose BPA: comparative implications on EMT, apoptosis, and TGF-β1 signaling in HepG2 cells

Bisphenol A (BPA) is an endocrine-disrupting chemical utilized in the manufacture of food packaging, dental materials, medical devices, children's toys, and baby products. Numerous studies have indicated the role of BPA in the etiology of many diseases such as diabetes, cardiovascular diseases, obesity, cancer, and chemotherapeutic resistance. However, the effects of BPA- chemotherapeutic combination remain to be investigated in different cell lines. Here, we demonstrate that low dose BPA and fulvestrant (estrogen receptor antagonist) combination synergistically decrease proliferation, promote cell migration and mesenchymal transition, switching from E-cadherin to N-cadherin expression Hepg2 cells. Moreover, we determined that low dose BPA may evoke susceptibility to apoptosis in HepG2 cells. The mechanism underlying these effects has been identified as increased TGF-β1 signaling. Our results provide an experimental basis for evaluating the potential health risks of low-dose BPA for fulvestrant therapy in hepatocytes.

Bisphenol analogs AF, S and F: Effects on functional characteristics of porcine granulosa cells

In order to replace industrial functions of the restricted endocrine disruptor bisphenol A (BPA), its structural analogs are increasingly employed without adequate assessment of their biological actions. Our study examined effects of the bisphenols AF (BPAF), S (BPS) and F (BPF), on functions of porcine ovarian granulosa cells (GCs) with the focus on viability, steroid production (10^-9-10^-4M), and expression of factors (10^-9-10^-5M) important for the follicle development: vascular endothelial growth factor A (VEGFA), matrix metalloproteinase 9 (MMP9), forkhead box O1 (FOXO1), and aryl hydrocarbon receptor (AHR). Cell viability was not impaired by the bisphenol analogs, except for the highest BPAF concentration (10^-4M). While the lower concentrations of the bisphenols were without effect, each of them reduced follicle-stimulating hormone (FSH)-induced progesterone synthesis at the highest dose. Estradiol synthesis was sensitive to BPS, inhibitory effects of which were manifested from the concentration of 10^-6M. Treatment of GCs with the selected bisphenol concentrations did not result in marked alterations in steroidogenic enzyme expression. Bisphenols did not significantly modulate VEGFA mRNA expression or output either under basal or FSH-stimulated conditions. BPF at 10^-5M increased MMP9 expression in FSH-stimulated cells. FSH upregulated FOXO1 expression, however, none of the bisphenols significantly affected FOXO1 levels either in basal or in FSH-stimulated conditions. AHR mRNA expression remained unchanged after bisphenol treatment. Although the significant effects of BPAF, BPS and BPF appeared only at supraphysiological doses, the results obtained indicate that BPA analogs are not inert with regard to ovarian physiology.

Identification of Potential Bisphenol A (BPA) Exposure Biomarkers in Ovarian Cancer

Endocrine-disrupting chemicals (EDCs) can exert multiple deleterious effects and have been implicated in carcinogenesis. The xenoestrogen Bisphenol A (BPA) that is found in various consumer products has been involved in the dysregulation of numerous signalling pathways. In this paper, we present the analysis of a set of 94 genes that have been shown to be dysregulated in presence of BPA in ovarian cancer cell lines since we hypothesised that these genes might be of biomarker potential. This study sought to identify biomarkers of disease and biomarkers of disease-associated exposure. In silico analyses took place using gene expression data extracted from The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) databases. Differential expression was further validated at protein level using immunohistochemistry on an ovarian cancer tissue microarray. We found that 14 out of 94 genes are solely dysregulated in the presence of BPA, while the remaining 80 genes are already dysregulated (p-value < 0.05) in their expression pattern as a consequence of the disease. We also found that seven genes have prognostic power for the overall survival in OC in relation to their expression levels. Out of these seven genes, Keratin 4 (KRT4) appears to be a biomarker of exposure-associated ovarian cancer, whereas Guanylate Binding Protein 5 (GBP5), long intergenic non-protein coding RNA 707 (LINC00707) and Solute Carrier Family 4 Member 11 (SLC4A11) are biomarkers of disease. BPA can exert a plethora of effects that can be tissue- or cancer-specific. Our in silico findings generate a hypothesis around biomarkers of disease and exposure that could potentially inform regulation and policy making.

A comprehensive review on the carcinogenic potential of bisphenol A: clues and evidence

Bisphenol A [BPA; (CH₃)₂C(C₆H₄OH)₂] is a synthetic chemical used as a precursor material for the manufacturing of plastics and resins. It gained attention due to its high chances of human exposure and predisposing individuals at extremely low doses to diseases, including cancer. It enters the human body via oral, inhaled, and dermal routes as leach-out products. BPA may be anticipated as a probable human carcinogen. Studies using in vitro cell lines, rodent models, and epidemiological analysis have convincingly shown the increasing susceptibility to cancer at doses below the oral reference dose set by the Environmental Protection Agency for BPA. Furthermore, BPA exerts its toxicological effects at the genetic and epigenetic levels, influencing various cell signaling pathways. The present review summarizes the available data on BPA and its potential impact on cancer and its clinical outcome.

The Cell-Free Expression of MiR200 Family Members Correlates with Estrogen Sensitivity in Human Epithelial Ovarian Cells

Exposure to physiological estrogens or xenoestrogens (e.g., zearalenone or bisphenol A) increases the risk for cancer. However, little information is available on their significance in ovarian cancer. We present a comprehensive study on the effect of estradiol, zearalenone and bisphenol A on the phenotype, mRNA, intracellular and cell-free miRNA expression of human epithelial ovarian cell lines. Estrogens induced a comparable effect on the rate of cell proliferation and migration as well as on the expression of estrogen-responsive genes (GREB1, CA12, DEPTOR, RBBP8) in the estrogen receptor α (ERα)-expressing PEO1 cell line, which was not observable in the absence of this receptor (in A2780 cells). The basal intracellular and cell-free expression of miR200s and miR203a was higher in PEO1, which was accompanied with low ZEB1 and high E-cadherin expression. These miRNAs showed a rapid but intermittent upregulation in response to estrogens that was diminished by an ERα-specific antagonist. The role of ERα in the regulation of the MIR200B-MIR200A-MIR429 locus was further supported by publicly available ChIP-seq data. MiRNA expression of cell lysates correlated well with cell-free miRNA expression. We conclude that cell-free miR200s might be promising biomarkers to assess estrogen sensitivity of ovarian cells.

Hypothalamic reproductive neurons communicate through signal transduction to control reproduction

Gonadotropin-releasing hormone (GnRH) neurons in the hypothalamus coordinate fertility and puberty. In order to achieve successful reproductive capacity, they receive signals from the periphery and from other hypothalamic neurons that coordinate energy homeostasis. Hormones, such as estradiol, insulin, leptin, and adiponectin, act directly or indirectly on GnRH and its associated reproductive neurons. Nutrients like glucose and fatty acids can also affect reproductive neurons to signal nutrient availability. Additionally, acute and chronic inflammation is reported to detrimentally affect GnRH and kisspeptin expression. All of these cues activate signal transduction pathways within neurons that lead to the changes in GnRH neuronal function. The signalling pathways can also be dysregulated by endocrine disrupting chemicals, which impair fertility by misappropriating common signalling pathways. The complex mechanisms controlling the levels of GnRH during the reproductive cycle rely on a carefully orchestrated set of signal transduction events to regulate the positive and negative feedback arms of the hypothalamic-pituitary-gonadal axis. If these signalling events are dysregulated, this will result is a downregulatory event leading to hypogonadal hypogonadism with decreased or absent fertility. Therefore, an understanding of the mechanisms involved in distinct neuronal signalling could provide an advantage to inform therapeutic interventions for infertility and reproductive disorders.

Boswellic Acid Synergizes With Low-Level Ionizing Radiation to Modulate Bisphenol Induced-Lung Toxicity in Rats by Inhibiting JNK/ERK/c-Fos Pathway

Bisphenol A (BPA) is a low molecular weight chemical compound that has a deleterious effect on the endocrine system. It was used in plastics manufacturing with injurious effects on different body systems. Occupational exposure to low-level ionizing radiation (<1 Gy) is shown to attenuate an established inflammatory process and therefore enhance cell protection. Therefore, the objective of this study was to investigate the protective effect of boswellic acid (BA) accompanied by whole-body low-dose gamma radiation (γ-R) against BPA-induced lung toxicity in male albino rats. BPA intoxication induced with 500 mg/kg BW. Rats received 50 mg BA/kg BW by gastric gavage concomitant with 0.5 Gy γ-R over 4 weeks. The immunoblotting and biochemical results revealed that BA and/or γ-R inhibited BPA-induced lung toxicity by reducing oxidative damage biomolecules; (MDA and NADPH oxidase gene expression), inflammatory indices (MPO, TNF-α, IL-6, and gene expression of CXCR-4). Moreover, BA and or/γ-R ameliorated the lung inflammation via regulation of the JNK/ERK/c-Fos and Nrf2/ HO-1 signaling pathways. Interestingly, our data demonstrated that BA in synergistic interaction with γ-R is efficacious control against BPA-induced lung injury via anti-oxidant mediated anti-inflammatory activities.

Urinary bisphenol A and its interaction with ESR1 genetic polymorphism associated with non-small cell lung cancer: findings from a case-control study in Chinese population

Bisphenol A (BPA), a well-known endocrine disruptor, was reported to promote migration and invasion of lung cancer cells, but findings in human study is absent. A case-control study in Chinese population was conducted to evaluate the association between BPA exposure and non-small cell lung cancer (NSCLC), and explore the interaction between BPA exposure and estrogen-related genetic polymorphism on NSCLC. BPA concentrations were measured in urine samples using an UHPLC-MS method and rs2046210 in estrogen receptor α (ESR1) gene was genotyped by TaqMan genotyping system. Logistic regression was performed to estimate odds ratios (OR) and 95% confidence intervals (95% CI) for the association analyses. As a result, 615 NSCLC cases and 615 healthy controls were enrolled from Wuhan, central China. The mean age was 58.0 (SD: 7.9) years old for controls and 59.2 (SD: 8.8) years old for cancer cases. The creatinine-adjusted BPA levels were significantly higher in NSCLC cases than that in healthy controls (median: 0.97 vs 0.73 μg/L, P < 0.001). Exposure to high levels of BPA was significantly associated with NSCLC (adjusted OR = 1.91, 95%CI: 1.39-2.62, P < 0.001 for the highest quartile). We also observed a shallow concave dose-response relationship about the overall association between BPA and NSCLC. Moreover, interaction analyses showed that BPA exposure interacted multiplicatively with rs2046210, with a marginal P value (P = 0.049), to contribute to NSCLC. In conclusion, exposure to high levels BPA may be associated with NSCLC and the relationship may be modified by genetic polymorphism in ESR1.

How microplastic components influence the immune system and impact on children health: Focus on cancer

BACKGROUND

As a result of human socioeconomic activity, industrial wastes have increased distressingly. Plastic pollution is globally distributed across the world due to its properties of buoyancy and durability. A big health hazard is the sorption of toxicants to plastic while traveling through the environment. Two broad classes of plastic-related chemicals are of critical concern for human health-bisphenols and phthalates. Bisphenol A (BPA) is an endocrine-disruptor compound (EDC) with estrogenic activity. It is used in the production of materials that are used daily. The endocrine modulating activity of BPA and its effects on reproductive health has been widely studied. BPA also has effects on the immune system; however, they are poorly investigated and the available data are inconclusive. Phthalates are also EDCs used as plasticizers in a wide array of daily-use products. Since these compounds are not covalently bound to the plastic matrix, they easily leach out from it, leading to high human exposure. These compounds exert several cell effects through modulating different endocrine pathways, such as estrogen, androgen, peroxisome proliferator-activated receptor gamma, and arylhydrocarbon receptor pathways. The exposure to both classes of plastic derivatives during critical periods has detrimental effects on human health.

METHODS

In this review, we have compiled the most important of their perinatal effects on the function of the immune system and their relationship to the development of different types of cancer.

RESULTS/CONCLUSION

The administration of bisphenols and phthalates during critical stages of development affects important immune system components, and the immune function; which might be related to the development of different diseases including cancer.

Bisphenol A and polychlorinated biphenyls enhance the cancer stem cell properties of human ovarian cancer cells by activating the WNT signaling pathway

Cancer stem cells (CSCs) are a very small subpopulation that have stem-cell qualities, such as exhibiting self-renewal, immortality, and pluripotency, and the capability to differentiate into different tumor cell subtypes. CSCs contribute to tumor onset, expansion, metastasis, resistance and recurrence. Meanwhile, organic pollutants, including nonpersistent pollutants, such as bisphenol A (BPA), and persistent pollutants, such as polychlorinated biphenyls (PCBs), are toxic chemicals that can be readily ingested via dietary exposure and other exposure routes and can accumulate through the food chain. Many organic pollutants increase the risk of ovarian cancer depending on their estrogenic effects. Nonetheless, most previous studies have focused on the toxic effects of these pollutants on the proliferation, metastasis and development of ovarian cancer cells. However, little research has investigated the adverse effect of these pollutants on ovarian cancer stem cells. The current study found that BPA, PCB126 and PCB153 greatly enhanced the formation of cancer stem-like cell spheres of OVCAR-3 cells (human ovarian cancer cells) under low-dose exposure. In parallel, the CD44^highCD24^low cell subpopulation was increased in treated cells relative to untreated cells. Elevated expression of cancer stem cell markers, including ALDH1A1, CD133, SOX2, NANOG and OCT4, was demonstrated in treated cells compared to untreated cells. In summary, these data demonstrate that the oncogenic effects of pollutants can be evaluated according to changes in caner stem cell properties.

Recovery From a Myocardial Infarction Is Impaired in Male C57bl/6 N Mice Acutely Exposed to the Bisphenols and Phthalates That Escape From Medical Devices Used in Cardiac Surgery

Bisphenols and phthalates leach from medical devices, and this exposure is likely to increase in postcardiac surgery patients. Previous studies suggest that such chemical exposure may impact recovery and wound healing, yet the direct effects of bisphenols and phthalates are unknown in this context. To study the direct effect of clinically based chemical exposures, we measured the metabolites representative of 6 bisphenols and 10 phthalates in men before and after cardiac surgery and then replicated this exposure in a mouse model of cardiac surgery and assessed survival, cardiac function and inflammation. Bisphenol A (BPA), di-ethyl hexyl phthalate (DEHP), butylbenzyl phthalate, di-isodecyl phthalate, and di-n-butyl phthalate metabolites were increased after surgery. DEHP exposure predominated, was positively correlated with duration on the cardiopulmonary bypass machine and exceeded its tolerable daily intake limit by 37-fold. In vivo, C57bl/6 N male mice treated with BPA+phthalates during recovery from surgery-induced myocardial infarction had reduced survival, greater cardiac dilation, reduced cardiac function and increased infiltration of neutrophils, monocytes and macrophages suggesting impaired recovery. Of interest, genetic ablation or estrogen receptor beta (ERβ) antagonism did not improve recovery and replacement of DEHP with tri-octyl trimellitate or removal of BPA from the mixture did not ameliorate these effects. To examine the direct effects on inflammation, treatment of human THP-1 macrophages with BPA and phthalates induced a dysfunctional proinflammatory macrophage phenotype with increased expression of M1-type macrophage polarization markers and MMP9 secretion, yet reduced phagocytic activity. These results suggest that chemicals escape from medical devices and may impair patient recovery.

Bisphenol A Exposure Enhances Endometrial Stromal Cell Invasion and Has a Positive Association with Peritoneal Endometriosis

Results of previous epidemiology studies on BPA exposure and endometriosis (EMs) risk were inconsistent, and were limited by inappropriate control selection, incorrect BPA detection method, and the generalization of different subtypes of EMs. Upregulated matrix metalloproteinase (MMP) 2 and MMP9 are involved in the development of EMs. We conducted a case-control study among 120 EMs patients and 100 healthy women to evaluate the relationships between BPA exposure and MMP2, MMP9 expressions, and the risk of EMs subtypes. Besides, we used human endometrial stromal cell lines (HESCs) to investigate the underlying mechanisms. Creatinine-adjusted urinary BPA concentrations were positively correlated with serum MMP2, MMP9 levels, and the risk of peritoneal EMs (third vs lowest quartile: OR 4.92, 95% CI 1.47, 16.50; fourth versus lowest quartile: OR 3.70, 95% CI 1.07, 12.74, P_trend = 0.030). The risk of peritoneal EMs increased approximately tenfold when creatinine-adjusted urinary BPA concentration was 2 μg/g. In vitro study found that BPA exposure increased MMP2, MMP9 expressions in a dose-dependent manner. The effects of BPA on HESCs could be blocked by G protein-coupled estrogen receptor (GPER) inhibitor or mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) inhibitor. This study provides evidence that BPA exposure promotes peritoneal EMs, and raises a concern about the potential toxicity of BPA on the female reproductive system.

High bisphenol A concentrations augment the invasiveness of tumor cells through Snail-1/Cx43/ERRγ-dependent epithelial-mesenchymal transition

Bisphenol A (BPA) is commonly present in plastics used for food storage and preservation. The release of BPA from these products results in a permanent human exposition to BPA; however, the quality and quantity of BPA adverse effects remain a matter of controversy. The common presence of BPA in the human environment and the controversies concerning the relations of human exposition to BPA and cancer incidence justify the research on the interactions between BPA and pro-metastatic signaling in cancer cells. Here, we describe a novel BPA-reactive signaling axis that induces the epithelial-mesenchymal transition (EMT) in lung adenocarcinoma A549 cells. BPA exerted negligible effects on their properties in a wide range of concentrations (10 nM - 100 nM), whereas it considerably induced A549 invasiveness at high concentrations (10 μM). The BPA-induced EMT was illustrated by morphologic changes, E/N-cadherin switch and vimentin/Snail-1/connexin(Cx)43 up-regulation in A549 populations. It was followed by enhancement of A549 drug-resistance. Corresponding effects of BPA were observed in prostate cancer cell populations. Concomitantly, we observed increased levels and perinuclear accumulation of estrogen-related receptor gamma (ERRγ) in BPA-treated cells, its interactions with Cx43/Snail-1, and the corresponding effects of phenol red on A549 cells. Collectively, these data identify a novel, pro-metastatic Snail-1/Cx43/ERRγ signaling pathway. Its reactivity to BPA underlies the induction of cancer cells' invasiveness in the presence of high BPA concentrations in vitro. Thus, the chronic exposition of cancer cells to extrinsic and intrinsic BPA should be considered as a potential obstacle in a cancer therapy.

Apelin abrogates the stimulatory effects of 17β-estradiol and insulin-like growth factor-1 on proliferation of epithelial and granulosa ovarian cancer cell lines via crosstalk between APLNR and ERα/IGF1R

Apelin and chemerin are adipocytokines that play important roles in many physiological and pathological processes throughout the body. Our previous study demonstrated that these two adipokines are expressed and secreted by epithelial and granulosa cancer cell lines. 17β-estradiol (E2) and insulin-like growth factor-1 (IGF-1) are important regulators of ovarian functions, and their roles are well known. This study investigated whether apelin and chemerin regulate proliferation and apoptosis of epithelial (OVCAR-3) and granulosa (COV434) ovarian cancer cell lines by interacting with E2 and IGF-1. Apelin and chemerin did not affect caspase-3 activation in either cell line. However, apelin abrogated the stimulatory effects of E2 on proliferation of OVCAR-3 cells and of IGF-1 on proliferation of COV434 cells independently of ERK1/2 and PI3K via crosstalk of apelin receptor with estrogen receptor alpha and IGF-1 receptor, respectively.

The adverse health effects of bisphenol A and related toxicity mechanisms

Bisphenol A (BPA) is an industrial component commonly used in synthesis of polycarbonate plastics, epoxy resin and other polymer materials. Due to its mass productions and widespread applications, the presence of BPA is ubiquitous in the environment. BPA can enter the body via different ways such as digestive tract, respiratory tract and dermal tract. As an endocrine disruptor, BPA has estrogen-like and anti-androgen effects causing damages to different tissues and organs, including reproductive system, immune system and neuroendocrine system, etc. Recently, it has been shown that BPA could induce carcinogenesis and mutagenesis in animal models. Here, the underlying mechanisms of BPA-induced multi-organ toxicity were well summarized, involving the receptor pathways, disruption of neuroendocrine system, inhibition of enzymes, modulation of immune and inflammatory responses, as well as genotoxic and epigenetic mechanisms. The aim of this review is to compile the available current research data regarding BPA and provide an overview of the current status of BPA exposure and relevant health effects covering reproductive, developmental, metabolic, immuno, respiratory, hepatic and renal toxicity and carcinogenesis of BPA. This review provides comprehensive data of BPA toxicity on human health and related mechanisms. We also identify any missing data which should be addressed by further studies.

Low Dose of Bisphenol A Modulates Ovarian Cancer Gene Expression Profile and Promotes Epithelial to Mesenchymal Transition Via Canonical Wnt Pathway

The xenoestrogen bisphenol A (BPA) is a synthetic endocrine disrupting chemical, having the potential to increase the risk of hormone-dependent ovarian cancer. Thus, a deeper understanding of the molecular and cellular mechanisms is urgently required in the novel cell models of ovarian cancer which express estrogen receptors. To understand the possible mechanisms underlying the effects of BPA, human ovarian adenocarcinoma SKOV3 cells were exposed to BPA (10 or 100 nM) or 0.1% DMSO for 24 h, and then global gene expression profile was determined by high-throughput RNA sequencing. Also, enrichment analysis was carried out to find out relevant functions and pathways within which differentially expressed genes were significantly enriched. Transcriptomic analysis revealed 94 differential expression genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses indicated that these genes related to tumorigenesis and metastasis. Further studies were carried out to validate the results of functional annotation, which indicated that BPA (10 and 100 nM) increased migration and invasion as well as induced epithelial to mesenchymal transitions in SKOV3 and A2780 cells. Accordingly, environmentally relevant-dose BPA activated the canonical Wnt signaling pathway. Our study first comprehensively analyzed the possible mechanisms underlying the effects of BPA on ovarian cancer. Environmentally relevant doses of BPA modulated the gene expression profile, promoted epithelial to mesenchymal transition progress via canonical Wnt signaling pathway of ovarian cancer.

Bisphenol AF promotes estrogen receptor-positive breast cancer cell proliferation through amphiregulin-mediated crosstalk with receptor tyrosine kinase signaling

Exposure to bisphenol A (BPA), an endocrine-disrupting compound, is associated with increased risk of estrogen-related diseases, including estrogen receptor-positive (ER⁺) breast cancer. Although bisphenol analogs, i.e. bisphenol AF (BPAF), have replaced BPA in industrial settings, increasing data indicate that these alternatives may have similar or even more potent estrogenic effects. As such, BPAF exhibits increased ER binding affinities than BPA in biochemical assays. However, preclinical studies exploring the effects of BPAF on ER⁺ breast cancer are missing mechanistic data. Thus, we aimed to characterize the effects of BPAF on MCF-7 and T47D ER⁺ breast cancer cells with mechanistic insight. We found that BPAF promoted cell growth and cell cycle progression concurrently with BPAF-induced ERα transcriptional activity and ER-RTK signaling activation. ER signaling blockage revealed that BPAF-induced cell proliferation and ER-RTK crosstalk were ER-dependent. Gene expression data demonstrated that AREG is a sensitive target of BPAF in our in vitro models. Importantly, we determined that AREG upregulation is necessary for BPAF-induced cellular responses. Ultimately, our novel finding that AREG mediates BPAF-induced ER-RTK crosstalk in ER⁺ breast cancer cells supports future studies to characterize the impact of BPAF on human ER⁺ breast cancer risk and to assess the safety profile of BPAF.

A mini review of bisphenol A (BPA) effects on cancer-related cellular signaling pathways

Bisphenol A (BPA) is a plasticizer used widely in many industrial products and is now well established as an endocrine-disrupting chemical (EDC). BPA readily leaches out from these products into the environment and into foodstuffs (from packaging materials) and human exposure can be considerable. Many studies have shown that BPA exposure is associated with a range of chronic human health conditions, including diabetes, cardiovascular disorders, polycystic ovarian disease, hepatotoxicity, and various types of cancer. BPA exerts its effects through deregulating cell signaling pathways associated with cell growth, proliferation, migration, invasion, and apoptosis. Previous studies on the molecular mechanisms of BPA have illustrated a variety of pathways impaired at very low exposure concentrations and that stimulate cellular responses relating to tumorigenesis both in cancer onset and progression. In this mini review, the recent advancements made through in vitro analyses are reported on for the effect of BPA on various cellular signaling pathways focusing on the signaling pathways that play a major role in carcinogenesis.

From the Cover: Lifelong Exposure of C57bl/6n Male Mice to Bisphenol A or Bisphenol S Reduces Recovery From a Myocardial Infarction

Bisphenol A (BPA) leaches from plastics to contaminate foodstuffs. Analogs, such as bisphenol S (BPS), are now used increasingly in manufacturing. Greater BPA exposure has been correlated with exacerbation of cardiovascular disease, including myocardial infarction (MI). To test the hypothesis that bisphenol exposure impairs cardiac healing, we exposed C57bl/6n mice to water containing 25ng/ml BPA or BPS from conception and surgically induced an MI in adult male progeny. Increased early death and cardiac dilation, and reduced cardiac function were found post-MI in BPA- and BPS-exposed mice. Flow cytometry revealed increased monocyte and macrophage infiltration that correlated with increased chemokine C-C motif ligand-2 expression in the infarct. In vitro BPA and BPS addition increased matrix metalloproteinase-9 (MMP) protein and secreted activity in RAW264.7 macrophage cells suggesting that invivo increases in MMP2 and MMP9 in exposed infarcts were myeloid-derived. Bone marrow-derived monocytes isolated from exposed mice had greater expression of pro-inflammatory polarization markers when chemokine stimulated indicating an enhanced susceptibility to develop a pro-inflammatory monocyte population. Chronic BPA exposure of estrogen receptor beta (ERβ) deficient mice did not worsen early death, cardiac structure/function, or expression of myeloid markers after an MI. In contrast, BPS exposure of ERβ-deficient mice resulted in greater death and expression of myeloid markers. We conclude that lifelong exposure to BPA or BPS augmented the monocyte/macrophage inflammatory response and adverse remodeling from an MI thereby reducing the ability to survive and successfully recover, and that the adverse effect of BPA, but not BPS, is downstream of ERβ signaling.

The state of bisphenol research in the lesser developed countries of the EU: a mini-review

Bisphenol compounds are a class of chemical epoxy resins that are found throughout the world in food packaging, thermal paper products, dental materials, and more. These compounds were deemed to be safe until recently, when some studies noticed adverse effects at very low doses, due to the fact that bisphenol acts as an endocrine disruptor. Over the last ten years, studies have been performed to detect bisphenols (especially BPA) in serum and blood samples throughout the world. Essentially, the majority of the earth's population seems to have significantly measurable levels of bisphenol in their blood plasma or urine. However, the majority of the population is unaware that a potential danger may exist. The purpose of this mini-review is to report upon the state of bisphenol research in the lesser developed member-states of the European Union and to increase awareness of the exposure level and possible adverse health effects of this endocrine disruptor. The results show that only three of the most newly admitted members of the European Union have published research concerning the health effects and/or environmental exposure of EU citizens to bisphenol compounds. Those countries were Slovenia, Poland and the Czech Republic. The rest of the surveyed member-states had little or no published research in relation to bisphenol compounds. Furthermore, even the three nations referred to above still lagged far behind the more advanced EU member-states. The lack of research could translate into a lack of awareness amongst the citizenry of nearly half of the EU, and may be unnecessarily putting those EU citizens at an increased risk of exposure.

BCL6B suppresses proliferation and migration of colorectal carcinoma cells through inhibition of the PI3K/AKT signaling pathway

B‑cell CLL/lymphoma 6 member B (BCL6B), a BCL6‑homologous gene, has been reported to be a tumor suppressor that is silenced in a variety of human cancers, including colorectal cancer (CRC). Although it was recently demonstrated that reduced expression of BCL6B is associated with tumor stage and lymph node metastasis in CRC, little is known on whether BCL6B contributes to CRC development, or the related underlying mechanism. The aim of the present study was to detect BCL6B expression in CRC cells, and determine the molecular mechanisms underlying the role of BCL6B in CRC development by investigating cell proliferation and migration in vitro. As a result, BCL6B expression was found to be notably repressed in CRC cells compared with normal intestinal epithelial cells by reverse transcription‑polymerase chain reaction and western blot analysis. CRC cell proliferation was significantly inhibited by BCL6B upregulation, as indicated by MTT and colony‑forming assays. Cell apoptosis was markedly induced, as indicated by flow cytometry, and BCL6B‑transfected CRC cells exhibited decreased migration ability. Additionally, BCL6B overexpression diminished the phosphorylation level of AKT in CRC cells. These effects of BCL6B were empowered by treatment with the specific phosphoinositide 3 kinase (PI3K)/AKT inhibitor LY294002. Furthermore, overexpression of BCL6B resulted in upregulation of E‑cadherin and downregulation of cyclin D1 and matrix metalloproteinase‑9, which were strongly enhanced by LY294002. In conclusion, the findings of the present study demonstrated that BCL6B suppressed the proliferation and migration of CRC cells indirectly, via inhibition of PI3K.

Bisphenol A and its derivatives decrease expression of chemerin, which reverses its stimulatory action in ovarian cancer cells

Chemerin is an adipocyte-secreted protein that associates with obesity, inflammation, metabolic dysfunction, and carcinogenesis. Previous studies have shown human granulosa cells to produce bioactive chemerin and its receptor CMKLR1. In the present study, we demonstrated that the mRNA level of chemerin receptor is higher in a granulosa cell tumor cell line than in epithelial cancer cells, whereas chemerin expression and secretion were lower. Various exogenous factors, such as bisphenol A and its halogenated derivatives tetrabromobisphenol A and tetrachlorobisphenol A, can affect adipokine expression. For this reason, we investigated the effects of bisphenol A and its derivatives on the expression of chemerin and its receptor. At low nanomolar concentrations, BPA, TBBPA, and TCBPA decreased chemerin expression and secretion only in granulosa cell tumor COV434 cells by both peroxisome proliferator-activated receptor γ and estrogen receptor signaling pathways. Chemerin treatment had no effect on proliferation of ovarian non-cancer and cancer cell lines. However, we also found evidence to support the inhibition of BPA- and TBBPA-induced cell proliferation by chemerin. Taken together, our results indicate for the first time that BPA and its derivatives down-regulate chemerin expression, which can suppress the ability of BPA to induce proliferation. Moreover, both PPARγ and ERs were involved in the BPA-induced decrease in chemerin expression, and its ratio was crucial to exert these effects.

Adiponectin Reverses the Proliferative Effects of Estradiol and IGF-1 in Human Epithelial Ovarian Cancer Cells by Downregulating the Expression of Their Receptors

The expression of adiponectin receptors AdipoR1 and AdipoR2 has been reported in the human ovary and ovarian cancer tissues. Moreover, adiponectin has been reported to act as an anti-tumor factor by inhibiting cancer cell proliferation. Thus, we investigate whether adiponectin and its receptors influence ovarian cancer development. In the present study, we found that adiponectin was not expressed in the granulosa cell line (COV434), and epithelial ovarian cancer cell lines (OVCAR-3, SKOV-3, and Caov-3). Additionally, we found that AdipoR1 and AdipoR2 expression is lower in epithelial ovarian cancer cells than in granulosa tumor cells. Endogenous 17β-estradiol as well as exogenous estrogens, such as bisphenol A and its chlorinated and brominated analogs do not affect adiponectin receptor expression. We found that adiponectin inhibited the growth of OVCAR-3 and SKOV-3 cells, and that this effect was independent of apoptosis. Moreover, adiponectin reverses the stimulatory effects of 17β-estradiol and insulin-like growth factor 1 on cell proliferation by downregulating the expression of their receptors, whereas progesterone increased the sensitivity of cancer cells to adiponectin by upregulating AdipoR1 and AdipoR2 expression. These results suggest interactions between adiponectin and various ovarian steroid hormone and growth factor pathways in ovarian cancer cells.

The molecular mechanisms of action of the endocrine disrupting chemical bisphenol A in the development of cancer

The endocrine disrupting chemical (EDC) is an exogenous substance or mixture that alters the function of the endocrine system and consequently causes adverse effects in intact organisms. Bisphenol A (BPA), one of the most common endocrine disrupting chemicals is a carbon-based synthetic compound used in the production of water bottles, cans, and teeth suture materials. It is known to be a xenoestrogen as it interacts with estrogen receptors and acts as agonist or antagonist via estrogen receptor-dependent signaling pathways. BPA has been associated with serious health effects in humans and wildlife. It elicits several endocrine disorders and plays a role in the pathogenesis of several hormone-dependent tumors such as breast, ovarian, prostate cancer and others. More complicate to this picture, its effects rely on several and diverse molecular and epigenetic mechanisms that converge upon endocrine and reproductive systems. The present review gives an overview of general hazards of BPA, its epigenetic modifications and the molecular mechanisms of BPA action in different types of cancers as the increase in information about responses and action mechanisms of BPA may bring a better understanding of the risks of BPA exposure in humans and provide an important platform on which human health can be improved.

Resveratrol inhibits proliferation, migration and invasion via Akt and ERK1/2 signaling pathways in renal cell carcinoma cells

Recent studies have shown that resveratrol (RES) inhibits cancer cell growth, migration and invasion. Here, we evaluated RES in two human renal cell carcinoma (RCC) cell lines, ACHN and A498. We investigated the effects of RES on proliferation, cell morphology, colony formation, migration, and invasion. We used a proliferation assay to demonstrate that RES inhibited cell growth with IC₅₀ values 132.9±1.064μM in ACHN, and 112.8±1.191μM in A498, respectively. Using inverted contrast microscopy, we showed that RES reduced cell-to-cell contact and inhibited formation of filopodia. A wound healing assay showed that RES inhibited migration of RCC cells. A Transwell assay showed that RES inhibited RCC migration and invasion. Western blot analysis showed that RES suppresses expression of N-cadherin, Vimentin, Snail, MMP-2, MMP-9, p-Akt and p-ERK1/2, but increased expression of E-cadherin and TIMP-1. In the presence of PD98059, the inhibitor of ERK1/2 pathway, we repeated all of the above experiments, showed that RES acted via the ERK1/2 pathway. Taken together, our results suggested that RES suppressed RCC cell proliferation, migration, and invasion in a concentration- and time-dependent manner. These effects likely resulted from inactivation of the Akt and ERK1/2 signaling pathways.