Role of foxj1 and estrogen receptor alpha in ciliated epithelial cell differentiation of the neonatal oviduct

Hormonal regulation of cilia in the female reproductive tract

This review intends to bridge the gap between our knowledge of steroid hormone regulation of motile cilia and the potential involvement of the primary cilium focusing on the female reproductive tract functions. The review emphasizes hormonal regulation of the motile and primary cilia in the oviduct and uterus. Steroid hormones including estrogen, progesterone, and testosterone act through their cognate receptors to regulate the development and biological function of the reproductive tracts. These hormones modulate motile ciliary beating and, in some cases, primary cilia function. Dysfunction of motile or primary cilia due to genetic anomalies, hormone imbalances, or loss of steroid hormone receptors impairs mammalian fertility. However, further research on hormone modulation of ciliary function, especially in the primary cilium, and its signaling cascades will provide insights into the pathogenesis of mammalian infertility and the development of contraceptives or infertility treatments targeting primary and/or motile cilia.

Classical Estrogen Signaling in Ciliated Epithelial Cells of the Oviduct Is Nonessential for Fertility in Female Mice

Ciliary action performs a critical role in the oviduct (Fallopian tube) during pregnancy establishment through sperm and egg transport. The disruption of normal ciliary function in the oviduct affects oocyte pick-up and is a contributing factor to female infertility. Estrogen is an important regulator of ciliary action in the oviduct and promotes ciliogenesis in several species. Global loss of estrogen receptor α (ESR1) leads to infertility. We have previously shown that ESR1 in the oviductal epithelial cell layer is required for female fertility. Here, we assessed the role of estrogen on transcriptional regulation of ciliated epithelial cells of the oviduct using single-cell RNA-sequencing analysis. We observed minor variations in ciliated cell genes in the proximal region (isthmus and uterotubal junction) of the oviduct. However, 17β-estradiol treatment had little impact on the gene expression profile of ciliated epithelial cells. We also conditionally ablated Esr1 from ciliated epithelial cells of the oviduct (called ciliated Esr1d/d mice). Our studies showed that ciliated Esr1d/d females had fertility rates comparable to control females, did not display any disruptions in preimplantation embryo development or embryo transport to the uterus, and had comparable cilia formation to control females. However, we observed some incomplete deletion of Esr1 in the ciliated epithelial cells, especially in the ampulla region. Nevertheless, our data suggest that ESR1 expression in ciliated cells of the oviduct is dispensable for ciliogenesis and nonessential for female fertility in mice.

Developing a reproducible protocol for culturing functional confluent monolayers of differentiated equine oviduct epithelial cells

We describe the development of two methods for obtaining confluent monolayers of polarized, differentiated equine oviduct epithelial cells (EOEC) in Transwell inserts and microfluidic chips. EOECs from the ampulla were isolated post-mortem and seeded either (1) directly onto a microporous membrane as differentiated EOECs (direct seeding protocol) or (2) first cultured to a confluent de-differentiated monolayer in conventional wells, then trypsinized and seeded onto a microporous membrane (re-differentiation protocol). Maintenance or induction of EOEC differentiation in these systems was achieved by air-liquid interface introduction. Monolayers cultured via both protocols were characterized by columnar, cytokeratin 19-positive EOECs in Transwell inserts. However, only the re-differentiation protocol could be transferred successfully to the microfluidic chips. Integrity of the monolayers was confirmed by transepithelial resistance measurements, tracer flux and the demonstration of an intimate network of tight junctions. Using the direct protocol, 28% of EOECs showed secondary cilia at the apical surface in a diffuse pattern. In contrast, re-differentiated polarized EOECs rarely showed secondary cilia in either culture system (>90% of the monolayers showed <1% ciliated EOECs). Occasionally (5-10%), re-differentiated monolayers with 11-27% EOECs with secondary cilia in a diffuse pattern were obtained. Additionally, nuclear progesterone receptor expression was found to be inhibited by simulated luteal phase hormone concentrations, and sperm binding to cilia was higher for re-differentiated EOEC monolayers exposed to estrogen-progesterone concentrations mimicking the follicular rather than luteal phase. Overall, a functional equine oviduct model was established with close morphological resemblance to in vivo oviduct epithelium.

Gender differences in non-cystic fibrosis bronchiectasis severity and bacterial load: the potential role of hormones

Non cystic-fibrosis bronchiectasis (NCFB) is a complex chronic respiratory disease, characterised by excessive sputum production and abnormal permanent dilation of bronchi. Mucus accumulation leads to recurrent bacterial infections and increased bacterial load, causing vicious cycles of structural damage and decreased lung function. Respiratory physiotherapy management of NCFB includes airway clearance techniques and use of nebulised, hypertonic saline. Despite advances in treatment, a consistent relationship has been observed between gender and disease occurrence, with a higher prevalence amongst females. Furthermore, NCFB presents most aggressively amongst post-menopausal females, a group likely exposed to higher levels of progesterone (P4) over a longer period of time. The effects of gender-specific hormones on bacterial load and physiotherapy management of people living with NCFB remain unknown. The aim of this narrative review was to discuss the potential influence of gender specific hormones on NCFB disease progression and influence on physiotherapy, medical management and future research. SCOPUS and PUBMED electronic databases were used to conduct searches for relevant studies using specific inclusion and exclusion criteria. Secondary inclusion of relevant literature was obtained from primary paper references. Previous literature suggests that P4 may impair Cilia Beat Frequency (CBF) in airway epithelium. Reduction in CBF may further reduce ability to expectorate amongst individuals with NCFB, increasing bacterial load and likelihood of exacerbations, negatively impacting on disease progression. Furthermore, coadministration of Estrogen has been suggested to offer opposing effects to that of P4 only. These findings question whether hormonal levels may be monitored, controlled and optimised within management and treatment of females with NCFB to improve airway clearance, reduce exacerbations and improve quality of life. Larger scale, long-term trials are required to further explore the effects of gender specific hormones on NCFB and the viability of treatment with hormone replacement therapy.

The reviews of this paper are available via the supplemental material section.

Estrogen and EGFR Pathways Regulate Notch Signaling in Opposing Directions for Multi-Ciliogenesis in the Fallopian Tube

The lumen of the fallopian tube (FT) is lined with columnar epithelium composed of secretory and ciliated cells, both of which are important for reproduction. However, the molecular mechanism regulating cell fate remains controversial. In this study, we established a primary culture system using porcine fallopian tube epithelial cells (FTECs) to study the differentiation mechanism. We found that estrogen promoted the differentiation of multi-ciliated cells (MCCs) through estrogen receptor β, following the reduction of DLL1, a ligand of Notch. Meanwhile, epidermal growth factor (EGF), a regulator of epithelial homeostasis and differentiation, suppressed ciliogenesis by the activation of Notch signaling. However, the estrogen pathway did not affect the activation of the EGF pathway. Taken together, the differentiation of MMCs in FT depends on the balance of EGF and estrogen signaling, either of which inhibits or stimulates the Notch signaling pathway respectively.

The external genitalia in juvenile Caiman latirostris differ in hormone sex determinate-female from temperature sex determinate-female

The broad-snouted caiman (Caiman latirostris) is a crocodilian species that inhabits South American wetlands. As in all other crocodilians, the egg incubation temperature during a critical thermo-sensitive window (TSW) determines the sex of the hatchlings, a phenomenon known as temperature-dependent sex determination (TSD). In C. latirostris, we have shown that administration of 17-β-estradiol (E₂) during the TSW overrides the effect of the male-producing temperature, producing phenotypic females (E₂SD-females). Moreover, the administration of E₂ during TSW has been proposed as an alternative way to improve the recovery of endangered reptile species, by skewing the population sex ratio to one that favors females. However, the ovaries of E₂SD-female caimans differ from those of TSD-females. In crocodilians, the external genitalia (i.e. clitero-penis structure or phallus) are sexually dimorphic and hormone-sensitive. Despite some morphological descriptions aimed to facilitate sexing, we found no available data on the C. latirostris phallus histoarchitecture or hormone dependence. Thus, the aims of this study were: (1) to establish the temporal growth pattern of the phallus in male and female caimans; (2) to evaluate histo-morphological features and the expression of estrogen receptor alpha (ERα) and androgen receptor (AR) in the phallus of male and female pre-pubertal juvenile caimans; and (3) to determine whether the phallus of TSD-females differs from the phallus of E₂SD-females. Our results demonstrated sexually dimorphic differences in the size and growth dynamics of the caiman external genitalia, similarities in the shape and spatial distribution of general histo-morphological compartments, and sexually dimorphic differences in innervation, smooth muscle fiber distribution, collagen organization, and ERα and AR expressions. The external genitalia of E₂SD-females differed from that of TSD-females in many histological features and in the expression of ERα and AR, resembling patterns described in males. Our results alert on the effects of estrogen agonist exposure during TSW and suggest that caution must be taken regarding the use of E₂SD as a procedure for wildlife population management.

Identification of grade and origin specific cell populations in serous epithelial ovarian cancer by single cell RNA-seq

Here we investigated different cell populations within ovarian cancer using single-cell RNA seq: fourteen samples from nine patients with differing grades (high grade, low grade and benign) as well as different origin sites (primary and metastatic tumor site, ovarian in origin and fallopian in origin). We were able to identify sixteen distinct cell populations with specific cells correlated to high grade tumors, low grade tumors, benign and one population unique to a patient with a breast cancer relapse. Furthermore the proportion of these populations changes from primary to metastatic in a shift from mainly epithelial cells to leukocytes with few cancer epithelial cells in the metastases. Differential gene expression shows myeloid lineage cells are the primary cell group expressing soluble factors in primary samples while fibroblasts do so in metastatic samples. The leukocytes that were captured did not seem to be suppressed through known pro-tumor cytokines from any of the cell populations. Single cell RNA-seq is necessary to de-tangle cellular heterogeneity for better understanding of ovarian cancer progression.

Long-term organoid culture reveals enrichment of organoid-forming epithelial cells in the fimbrial portion of mouse fallopian tube

A recent paradigm shift in ovarian cancer research is the finding that many ovarian cancers may originate from fallopian tube epithelial (FTE) cells. As tissue stem and progenitor cells often serve as cells of origin of cancer, a better understanding of FTE stem/progenitor cells and how they become transformed is essential for early detection and prevention of ovarian cancer. To facilitate study of FTE stem/progenitor cells in model systems, we established an organoid culture system for mouse FTE cells. We find that EPCAM+ mouse FTE cells can be stably cultured long-term under a minimal condition of activated EGF signaling and suppressed TGFbeta signaling. We show that both Notch and Wnt signaling are required for growth of FTE cells in organoids, and further activation of Wnt signaling supports their maturation toward the ciliated cell lineage. Lastly, by analyzing the frequency of organoid-forming cells in different portions of the fallopian tube (FT), we find that the distal portion of the FT, which includes the fimbria, is enriched with organoid-forming FTE stem cells.

NEDD9 promotes oncogenic signaling, a stem/mesenchymal gene signature, and aggressive ovarian cancer growth in mice

Neural precursor cell expressed, developmentally downregulated 9 (NEDD9) supports oncogenic signaling in a number of solid and hematologic tumors. Little is known about the role of NEDD9 in ovarian carcinoma (OC), but available data suggest elevated mRNA and protein expression in advanced stage high-grade cancers. We used a transgenic MISIIR-TAg mouse OC model combined with genetic ablation of Nedd9 to investigate its action in the development and progression of OC. A Nedd9-/- genotype delayed tumor growth rate, reduced incidence of ascites, and reduced expression and activation of signaling proteins including SRC, STAT3, E-cadherin, and AURKA. Cell lines established from MISIIR-TAg;Nedd9-/- and MISIIR-TAg;Nedd9+/+ mice exhibited altered migration and invasion. Growth of these cells in a syngeneic allograft model indicated that systemic Nedd9 loss in the microenvironment had little impact on tumor allograft growth, but in a Nedd9 wild-type background Nedd9-/- allografts exhibited significantly reduced growth, dissemination, and oncogenic signaling compared to Nedd9+/+ allografts. Gene expression analysis revealed that Nedd9+/+ tumors exhibited more mesenchymal "stem-like" transcriptional program, including increased expression of Aldh1a1 and Aldh1a2. Conversely, loss of Nedd9 resulted in increased expression of differentiation genes, including fallopian tube markers Foxj1, Ovgp1, and Pax8. Collectively, these data suggest that tumor cell-intrinsic Nedd9 expression promotes OC development and progression by broad induction of oncogenic protein signaling and stem/mesenchymal gene expression.

Adipocytes induce distinct gene expression profiles in mammary tumor cells and enhance inflammatory signaling in invasive breast cancer cells

Obesity is a known risk factor for breast cancer. Since obesity rates are constantly rising worldwide, understanding the molecular details of the interaction between adipose tissue and breast tumors becomes an urgent task. To investigate potential molecular changes in breast cancer cells induced by co-existing adipocytes, we used a co-culture system of different breast cancer cell lines (MCF-7 and T47D: ER+/PR+/HER2- and MDA-MB-231: ER-/PR-/HER2-) and murine 3T3-L1 adipocytes. Here, we report that co-culture with adipocytes revealed distinct changes in global gene expression pattern in the different breast cancer cell lines. Our microarray data revealed that in both ER+ cell lines, top upregulated genes showed significant enrichment for hormone receptor target genes. In triple-negative MDA-MB-231 cells, co-culture with adipocytes led to the induction of pro-inflammatory genes, mainly involving genes of the Nf-κB signaling pathway. Moreover, co-cultured MDA-MB-231 cells showed increased secretion of the pro-inflammatory interleukins IL-6 and IL-8. Using a specific NF-κB inhibitor, these effects were significantly decreased. Finally, migratory capacities were significantly increased in triple-negative breast cancer cells upon co-culture with adipocytes, indicating an enhanced aggressive cell phenotype. Together, our studies illustrate that factors secreted by adipocytes have a significant impact on the molecular biology of breast cancer cells.

Sex Steroid-Mediated Control of Oviductal Function in Cattle

In cattle, the oviduct is a tubular organ that connects the ovary and the uterus. The oviduct lumen stages a dynamic set of cellular and molecular interactions to fulfill the noble role of generating a new individual. Specific anatomical niches along the oviduct lumen provide the appropriate microenvironment for final sperm capacitation, oocyte capture and fertilization, and early embryo development and transport. To accomplish such complex tasks, the oviduct undergoes spatially and temporally-regulated morphological, biochemical, and physiological changes that are associated with endocrine events of the estrous cycle. Specifically, elevated periovulatory concentrations of estradiol (E2) and progesterone (P4) influence gene expression and morphological changes that have been associated positively to fertility in beef cattle. In this review, we explore how E2 and P4 influence oviductal function in the beginning of the estrous cycle, and prepare the oviductal lumen for interactions with gametes and embryos.

17β-Estradiol sensitizes ovarian surface epithelium to transformation by suppressing Disabled-2 expression

Estrogen replacement therapy increases the risk of human ovarian cancer and exogenous estradiol accelerates the onset of ovarian cancer in mouse models. This study uses primary cultures of mouse ovarian surface epithelium (OSE) to demonstrate that one possible mechanism by which estrogen accelerates the initiation of ovarian cancer is by up-regulation of microRNA-378 via the ESR1 pathway to result in the down-regulation of a tumour suppressor called Disabled-2 (Dab2). Estrogen suppression of Dab2 was reproducible in vivo and across many cell types including mouse oviductal epithelium and primary cultures of human ovarian cancer cells. Suppression of Dab2 resulted in increased proliferation, loss of contact inhibition, morphological dysplasia, and resistance to oncogene-induced senescence - all factors that can sensitize OSE to transformation. Given that DAB2 is highly expressed in healthy human OSE and is absent in the majority of ovarian tumours, this study has taken the first steps to provide a mechanistic explanation for how estrogen therapy may play a role in the initiation of ovarian cancer.

Integrated Analysis Reveals Tubal- and Ovarian-Originated Serous Ovarian Cancer and Predicts Differential Therapeutic Responses

Purpose: The relative importance of fallopian tube (FT) compared with ovarian surface epithelium (OSE) in the genesis of serous type of ovarian cancer (SOC) is still unsettled. Here, we followed an integrated approach to study the tissue origin of SOC, as well as its association with clinical outcome and response to therapeutic drugs.Experimental Design: A collection of transcriptome data of 80 FTs, 89 OSEs, and 2,668 SOCs was systematically analyzed to determine the characteristic of FT-like and OSE-like tumors. A molecular signature was developed for identifying tissue origin of SOC and then was used to reevaluate the prognostic genes and therapeutic biomarkers of SOC of different tissue origins. IHC staining of tissue array and functional experiments on a panel of ovarian cancer cell lines were used to further validate the key findings.Results: The expression patterns of tissue-specific genes, prognostic genes, and molecular markers all support a dualistic tissue origin of SOC, from either FT or OSE. A molecular signature was established to identify the tissue identity of SOCs. Surprisingly, the signature showed a strong association with overall survival (OSE-like vs. FT-like, HR = 4.16; 95% CI, 2.67-6.48; P < 10^-9). The pharmacogenomic approach revealed AXL to be a therapeutic target of the aggressive OSE-derived SOC.Conclusions: SOC has two subtypes originated from either FT or OSE, which show different clinical and pathologic features. Clin Cancer Res; 23(23); 7400-11. ©2017 AACR.

Spatial distribution of cannabinoid receptor 1 and fatty acid amide hydrolase in the cat ovary and oviduct

Involvement of the endocannabinoid system in female reproduction has been extensively described in humans with the cognate receptors and ligands being found in the ovaries and genital tract. In human, an imbalance of the endocannabinoid system is linked with both ectopic pregnancy and infertility. In bovine species anandamide levels regulate aspects of sperm-oviduct interaction. Here we report the immunohistochemical distribution of cannabinoid receptor 1 (CB1R) and fatty acid amide hydrolase (FAAH) in cat ovary and oviduct, using paraffin-embedded tissue samples and commercially available antibodies. We found a differential expression of both CB1R and FAAH during different stages of ovarian function and in the oviduct. CB1R was detected only in tertiary follicle granulosa cells while more immature follicles were negative. FAAH was instead found in ovarian pre-antral follicles, the oocyte cytoplasm, and in granulosa cells of primary, secondary and tertiary follicles. Secondary and tertiary follicles were also FAAH immunoreactive. Luteal cells were immunopositive for both CB1R and FAAH. Because CBR1 in oviduct was found only in ciliated cells, it might represent a specific marker at least in cats. In contrast, FAAH immunoreactivity was observed in both ciliated and non-ciliated cells. The present study may thus serve as the starting point for further investigations on the role of the endocannabinoid system in cat reproduction. Additional work will be needed to assess whether the morphological distribution of CB1R and FAAH changes in different conditions such as pre-pubertal age, follicular phase of the sexual cycle and pregnancy.

Estrogen receptor α is required for oviductal transport of embryos

Newly fertilized embryos spend the first few days within the oviduct and are transported to the uterus, where they implant onto the uterine wall. An implantation of the embryo before reaching the uterus could result in ectopic pregnancy and lead to maternal death. Estrogen is necessary for embryo transport in mammals; however, the mechanism involved in estrogen-mediated cellular function within the oviduct remains unclear. In this study, we show in mouse models that ciliary length and beat frequency of the oviductal epithelial cells are regulated through estrogen receptor α (ESR1) but not estrogen receptor β (ESR2). Gene profiling indicated that transcripts in the WNT/β-catenin (WNT/CTNNB1) signaling pathway were regulated by estrogen in mouse oviduct, and inhibition of this pathway in a whole oviduct culture system resulted in a decreased embryo transport distance. However, selective ablation of CTNNB1 from the oviductal ciliated cells did not affect embryo transport, possibly because of a compensatory mechanism via intact CTNNB1 in the adjacent secretory cells. In summary, we demonstrated that disruption of estrogen signaling in oviductal epithelial cells alters ciliary function and impairs embryo transport. Therefore, our findings may provide a better understanding of etiology of the ectopic pregnancy that is associated with alteration of estrogen signals.-Li, S., O'Neill, S. R. S., Zhang, Y., Holtzman, M. J., Takemaru, K.-I., Korach, K. S., Winuthayanon, W. Estrogen receptor α is required for oviductal transport of embryos.

Expression and localization of forkhead box protein FOXJ1 in S100β-positive multiciliated cells of the rat pituitary

S100β-positive cells exist in the marginal cell layer (MCL) of the adenohypophysis and follicle structure in the parenchyma of anterior lobe (ALFS) in pituitary. They have multiple functions as phagocytes or cells that regulate hormone secretion. Majority of S100β-positive cells in the adenohypophysis express sex determining region Y-box 2 protein (SOX2), a stem cell marker; therefore, S100β/SOX2 double positive cells are also considered as one type of stem/progenitor cells. MCL and ALFS are consisting of morphologically two types of cells, i.e., multiciliated cells and non-ciliated cells. However, the relationship between the S100β-positive cells and multiciliated cells in the pituitary is largely unknown. In the present study, we first immunohistochemically verified the feature of multiciliated cells in MCL and ALFS. We then examined the expression patterns of FOXJ1, an essential expression factor for multiciliated cell-differentiation, and SOX2 in the S100β-positive multiciliated cells by in situ hybridization and immunohistochemistry. We identified anew the S100β/SOX2/FOXJ1 triple positive multiciliated cells, and revealed that they were dispersed throughout the MCL and ALFS. These results indicate that the MCL and ALFS are consisting of morphologically and functionally distinct two types of cells, i.e., S100β/SOX2 double positive non-ciliated cells and S100β/SOX2/FOXJ1 triple positive multiciliated cells.

Expression of P450arom and Estrogen Receptor Alpha in the Oviduct of Chinese Brown Frog (Rana dybowskii) during Prehibernation

One specific physiological phenomenon of Chinese brown frog (Rana dybowskii) is that its oviduct expands prior to hibernation instead of expanding during the breeding period. In this study, we investigated the expression of P450arom and estrogen receptors α and β (ERα and ERβ) in the oviduct of Rana dybowskii during the breeding period and prehibernation. The results of the present study showed that there were significant differences in both oviductal weight and size with values markedly higher in prehibernation than in the breeding period. P450arom was observed in stromal tissue in both the breeding period and prehibernation. ERα was expressed in stromal tissue and epithelial cells in both periods, whereas ERβ could not be detected. The mean protein and mRNA levels of P450arom and ERα were significantly higher in prehibernation as compared to the breeding period. Besides, oviductal content of 17β-estradiol was also higher in prehibernation than in the breeding period. These results suggested that estrogen may play autocrine/paracrine roles mediated by ERα in regulating the oviductal hypertrophy during prehibernation.

Xenopus embryonic epidermis as a mucociliary cellular ecosystem to assess the effect of sex hormones in a non-reproductive context

Background

How important are sexual hormones beyond their function in reproductive biology has yet to be understood. In this study, we analyzed the effects of sex steroids on the biology of the embryonic amphibian epidermis, which represents an easily amenable model of non-reproductive mucociliary epithelia (MCE). MCE are integrated systems formed by multiciliated (MC), mucus-secreting (MS) and mitochondrion-rich (MR) cell populations that are shaped by their microenvironment. Therefore, MCE could be considered as ecosystems at the cellular scale, found in a wide array of contexts from mussel gills to mammalian oviduct.

Results

We showed that the natural estrogen (estradiol, E2) and androgen (testosterone, T) as well as the synthetic estrogen (ethinyl-estradiol, EE2), all induced a significant enhancement of MC cell numbers. The effect of E2, T and EE2 extended to the MS and MR cell populations, to varying degrees. They also modified the expression profile of RNA MCE markers, and induced a range of “non-typical” cellular phenotypes, with mixed identities and aberrant morphologies, as revealed by imaging analysis through biomarker confocal detection and scanning electron microscopy. Finally, these hormones also affected tadpole pigmentation, revealing an effect on the entire cellular ecosystem of the Xenopus embryonic skin.

Conclusions

This study reveals the impact in vivo, at the molecular, cellular, tissue and organism levels, of sex steroids on non-reproductive mucociliary epithelium biogenesis, and validates the use of Xenopus as a relevant model system in this field.

Endosalpingiosis as it relates to tubal, ovarian and serous neoplastic tissues: an immunohistochemical study of tubal and Müllerian antigens

OBJECTIVE

The origins and clinical significance of endosalpingiosis (ES), ectopic tubal epithelium, are not well understood. These investigations aim to characterize ES as it relates to normal fallopian tube, ovarian surface and serous neoplasms.

METHODS

A retrospective review of pathology reports from all prophylactic gynecologic surgeries from 2000 to 2010 was performed to assess the frequency of ES. Twenty-one archival specimens of ES, 6 normal fallopian tubes, 9 normal ovaries, 21 serous neoplasms and a commercially available ovarian tissue microarray were subjected to immunohistochemistry (IHC) with 11 tubal and Müllerian antigens. IHC staining was evaluated with a quantitative scoring system and scores were analyzed using MINITAB statistical software.

RESULTS

ES was noted in 3.5% of pathologic specimens from 464 prophylactic surgeries. The majority of antigens showed no significant differences (p > 0.05) in median IHC scores between ES and normal fallopian tube epithelium (nFTE), while they were significantly different (p < 0.05) from the ovarian surface epithelium (OSE). Median IHC scores were unchanged in ES tissues regardless of the location of ES or the presence of a concurrent serous neoplasm. Three antigens emerged as contemporary tubal and ES biomarkers: phospho-Smad2, BCL2 and FOXJ1. All 3 biomarkers were expressed in ES, nFTE and serous neoplasms, but not in OSE or other tumor types.

CONCLUSION

This study provides immunophenotypic evidence that ES is more similar to the nFTE than OSE. Further, ES biomarker expression closely resembles serous neoplasms strengthening the growing body of evidence that all Müllerian serous carcinomas arise from tubal-like epithelium.

Stem cell-like gene expression in ovarian cancer predicts type II subtype and prognosis

Although ovarian cancer is often initially chemotherapy-sensitive, the vast majority of tumors eventually relapse and patients die of increasingly aggressive disease. Cancer stem cells are believed to have properties that allow them to survive therapy and may drive recurrent tumor growth. Cancer stem cells or cancer-initiating cells are a rare cell population and difficult to isolate experimentally. Genes that are expressed by stem cells may characterize a subset of less differentiated tumors and aid in prognostic classification of ovarian cancer. The purpose of this study was the genomic identification and characterization of a subtype of ovarian cancer that has stem cell-like gene expression. Using human and mouse gene signatures of embryonic, adult, or cancer stem cells, we performed an unsupervised bipartition class discovery on expression profiles from 145 serous ovarian tumors to identify a stem-like and more differentiated subgroup. Subtypes were reproducible and were further characterized in four independent, heterogeneous ovarian cancer datasets. We identified a stem-like subtype characterized by a 51-gene signature, which is significantly enriched in tumors with properties of Type II ovarian cancer; high grade, serous tumors, and poor survival. Conversely, the differentiated tumors share properties with Type I, including lower grade and mixed histological subtypes. The stem cell-like signature was prognostic within high-stage serous ovarian cancer, classifying a small subset of high-stage tumors with better prognosis, in the differentiated subtype. In multivariate models that adjusted for common clinical factors (including grade, stage, age), the subtype classification was still a significant predictor of relapse. The prognostic stem-like gene signature yields new insights into prognostic differences in ovarian cancer, provides a genomic context for defining Type I/II subtypes, and potential gene targets which following further validation may be valuable in the clinical management or treatment of ovarian cancer.

Identification of quiescent, stem-like cells in the distal female reproductive tract

In fertile women, the endometrium undergoes regular cycles of tissue build-up and regression. It is likely that uterine stem cells are involved in this remarkable turn over. The main goal of our current investigations was to identify slow-cycling (quiescent) endometrial stem cells by means of a pulse-chase approach to selectively earmark, prospectively isolate, and characterize label-retaining cells (LRCs). To this aim, transgenic mice expressing histone2B-GFP (H2B-GFP) in a Tet-inducible fashion were administered doxycycline (pulse) which was thereafter withdrawn from the drinking water (chase). Over time, dividing cells progressively loose GFP signal whereas infrequently dividing cells retain H2B-GFP expression. We evaluated H2B-GFP retaining cells at different chase time points and identified long-term (LT; >12 weeks) LRCs. The LT-LRCs are negative for estrogen receptor-α and express low levels of progesterone receptors. LRCs sorted by FACS are able to form spheroids capable of self-renewal and differentiation. Upon serum stimulation spheroid cells are induced to differentiate and form glandular structures which express markers of mature Műllerian epithelial cells. Overall, the results indicate that quiescent cells located in the distal oviduct have stem-like properties and can differentiate into distinct cell lineages specific of endometrium, proximal and distal oviduct. Future lineage-tracing studies will elucidate the role played by these cells in homeostasis, tissue injury and cancer of the female reproductive tract in the mouse and eventually in man.

Mucinous adenocarcinoma developed from human fallopian tube epithelial cells through defined genetic modifications

Recent studies have suggested that some ovarian and pelvic serous carcinomas could originate from the fimbriated end of the distal fallopian tube. To test this hypothesis, we immortalized a normal human fallopian tube epithelial (FTE) cell line by using retrovirus-mediated overexpression of the early region of the SV40 T/t antigens and the human telomerase reverse transcriptase subunit (hTERT). These immortalized FTEs were then transformed by ectopic expression of oncogenic human HRAS (V12) . Tumorigenicity of the immortalized and/or transformed cells was subsequently tested by anchorage-independence growth assay and inoculation into nude mice via subcutaneous and intraperitoneal injection. As expected, the HRAS (V12) -transformed FTEs produced tumors through both subcutaneous and intraperitoneal injections, whereas no tumor growth was observed in immortalized FTEs. Unexpectedly, histopathological examination of tumors resulting from subcutaneous as well as intraperitoneal injections revealed largely poorly differentiated mucinous adenocarcinoma mixed with undifferentiated carcinoma. The tumor implants invaded extensively to the liver, colon, spleen, omentum, adrenal gland and renal capsule. Immunohistochemical staining of tumor cells showed positive staining for the epithelial cell markers cytokeratin AE1/AE3 and Müllerian lineage marker PAX8. Our study demonstrates that FTEs can generate poorly differentiated mucinous adenocarcinoma mixed with undifferentiated carcinoma through genetic modifications. Thus, we provide the first experimental evidence that fimbrial epithelial cells of the fallopian tube could be a potential source of ovarian mucinous adenocarcinoma.

Deletion of tuberous sclerosis 1 in somatic cells of the murine reproductive tract causes female infertility

Tumors develop with dysregulated activation of mammalian target of rapamycin (mTOR), the kinase activity of which is kept in an inactive state by a tumor suppressor dimer containing tuberous sclerosis 1 (TSC1) and TSC2. We examined whether conditional deletion of TSC1 by a knock-in allele of the anti-Müllerian hormone type 2 receptor (Amhr2) driving Cre expression and subsequent activation of mTOR in granulosa cells and in oviductal and uterine stromal cells affects fertility in female mice. Increased phosphorylation of ribosomal protein S6, a downstream target of activated mTOR, was observed in all AMHR2-expressing tissues examined, indicating loss of TSC1 activity. TSC1 deletion in granulosa cells led to the detection of significantly fewer primordial follicles in mutant mice at 12 wk, suggesting premature ovarian insufficiency, which might be related to the significantly increased time mutant mice spent in estrus. Although the number of good-quality ovulated oocytes was not significantly different compared with controls, there was a significantly higher number of degenerated oocytes after normal and superovulation, suggesting compromised oocyte quality, as well. Natural mating also showed severalfold higher numbers of degenerate bodies in the mutants that collected in bilateral swellings resembling hydrosalpinges that formed in all mice examined because of occlusion of the proximal oviduct. Attempts to transfer control embryos into mutant uteri also failed, indicating that implantation was compromised. Endometrial epithelial cells continued to proliferate, and quantitative RT-PCR showed that mucin 1 expression persisted during the window of implantation in mutant uteri, without any changes in progesterone receptor mRNA expression, suggesting a mechanism that does not involve disrupted estradiol-regulated progesterone receptor expression. Homozygous deletion of TSC1 in reproductive tract somatic tissues of mice rendered females completely infertile, which is likely due to these pleiotropic effects on follicle recruitment, oviductal development, and blastocyst implantation.

Mouse oviduct development

The oviduct, or Fallopian tube in humans, transports oocytes and sperm, serves as the site of fertilization, and supports early embryonic development. The oviduct is essential for fertility. In the mouse, the oviduct is a coiled, complex structure that develops from the simple embryonic Müllerian duct. The oviduct consists of four segments, including the infundibulum, ampulla, isthmus, and uterotubal junction. Additionally, the mouse oviduct forms coils, develops longitudinal folds, and undergoes both mesenchymal and epithelial differentiation. Oviduct development and differentiation occurs perinatally. Several signaling pathways have been found to be involved in oviduct formation, such as Wnt, Tgfβ, microRNA processing, as well as others. Overall, the process of oviduct development is poorly understood and can be utilized to further knowledge of epithelial-mesenchymal interactions, regulation of coiling, characteristics of pseudostratified epithelia, and smooth muscle differentiation.

Sex hormone-dependent regulation of cilia beat frequency in airway epithelium

Previous studies have demonstrated a female disadvantage in airway diseases, such as asthma and bronchiectasis. The basis for this sex disparity is unknown. We hypothesized that the female sex hormone, progesterone (P4), inhibits functions of the normal airway mucociliary apparatus. P4 receptor (PR) expression was evaluated in human lung and cultured primary human airway epithelial cells isolated from male and female lung transplant donors. PR expression was restricted to the proximal region of the cilia of airway epithelia, and was similar in men and women. Expression of isoform PR-B was more abundant than PR-A in cells from both sexes. Airway epithelial cell exposure to P4 decreased cilia beat frequency (CBF) by 42.3% (±7.2). Inhibition of CBF was prevented by coadministration of P4 with the active form of estrogen, 17β-estradiol, or the PR antagonist, mifepristone. P4 inhibition was time and dose dependent, with a significant decrease by 8 hours and maximal effect at 24 hours, accompanied by translocation of PR from the cilia to the nucleus. Inhibition of cilia beat was also prevented by treatment of cells with actinomycin D, suggesting that CBF inhibition is a transcriptionally mediated event. Together, these findings indicate that sex hormones influence the function of a key component of the mucociliary apparatus. These mechanisms may contribute to the sex disparity present in airway diseases and provide therapeutic targets for the treatment of these debilitating airway diseases.

Generation of human female reproductive tract epithelium from human embryonic stem cells

Background

Recent studies have identified stem/progenitor cells in human and mouse uterine epithelium, which are postulated to be responsible for tissue regeneration and proliferative disorders of human endometrium. These progenitor cells are thought to be derived from Müllerian duct (MD), the primordial female reproductive tract (FRT).

Methodology/Principal Findings

We have developed a model of human reproductive tract development in which inductive neonatal mouse uterine mesenchyme (nMUM) is recombined with green fluorescent protein (GFP)-tagged human embryonic stem cells (hESCs); GFP-hESC (ENVY). We demonstrate for the first time that hESCs can be differentiated into cells with a human FRT epithelial cell phenotype. hESC derived FRT epithelial cells emerged from cultures containing MIXL1⁺ mesendodermal precursors, paralleling events occurring during normal organogenesis. Following transplantation, nMUM treated embryoid bodies (EBs) generated epithelial structures with a typical MD phenotype that expressed the MD markers PAX2, HOXA10. Functionally, the hESCs derived FRT epithelium responded to exogenous estrogen by proliferating and secreting uterine-specific glycodelin A (GdA).

Conclusions/Significance

These data show nMUM can induce differentiation of hESC to form the FRT epithelium. This may provide a model to study early developmental events of the human FRT.

Transcriptional regulation of an axonemal central apparatus gene, sperm-associated antigen 6, by a SRY-related high mobility group transcription factor, S-SOX5

SOX5 is a transcription factor with homology to the high mobility group box region of the testis-determining factor, SRY. Both the mouse and human SOX5 genes encode a 48-kDa SOX5 protein (S-SOX5) that is only present in tissues containing cells with motile cilia/flagella. The mammalian sperm-associated antigen 6 gene (SPAG6) encodes an axoneme central apparatus protein. Because human and mouse SPAG6 gene promoters contain multiple potential binding sites for SOX5, SPAG6 gene regulation by S-SOX5 was investigated in BEAS-2B cells, a line derived from human bronchial cells. Like FOXJ1, a transcription factor known to be essential for motile ciliogenesis, S-SOX5 stimulated mouse and human SPAG6 promoter function in BEAS-2B cells, but the effect was abrogated when the SOX5 binding sites were mutated or deleted. S-SOX5 and FOXJ1 functioned cooperatively in stimulating SPAG6 promoter activity. The SPAG6 message was up-regulated when S-SOX5 was overexpressed in BEAS-2B cells, and silencing of S-SOX5 by RNA interference down-regulated SPAG6 transcripts. Chromatin immunoprecipitation and EMSA experiments demonstrated that S-SOX5 associates with the SPAG6 promoter directly. The present study demonstrates that SPAG6 is a S-SOX5 target gene, indicating a key role for S-SOX5 in the formation and function of motile cilia.

Primary ex vivo cultures of human fallopian tube epithelium as a model for serous ovarian carcinogenesis

Recent studies suggest that some serous ovarian carcinomas (SOCs) arise from the fallopian tube (FT) epithelium rather than the ovarian surface epithelium. This hypothesis places emphasis on the FT secretory epithelial cell as a cell-of-origin. Herein, we report the development of a novel ex vivo primary human FT epithelium culture system that faithfully recapitulates the in vivo epithelium, as shown by morphological, ultrastructural and immunophenotypic analyses. Mass spectrometry-based proteomics reveal that these cultures secrete proteins previously identified as biomarkers for ovarian cancer. We also use this culture system to study the response of the FT epithelium to genotoxic stress and find that the secretory cells exhibit a distinct response to DNA damage when compared with neighboring ciliated cells. The secretory cells show a limited ability to resolve the damage over time, potentially leaving them more susceptible to accumulation of additional mutagenic injury. This divergent response is confirmed with in situ studies using tissue samples, further supporting the use of this ex vivo culture system to investigate FT epithelial pathobiology. We anticipate that this novel culture system will facilitate the study of SOC pathogenesis, and propose that similar culture systems could be developed for other organ site-specific epithelia.

Both foxj1a and foxj1b are implicated in left-right asymmetric development in zebrafish embryos

The HNF-3/HFH-4/Foxj1, a transcription factor, has been reported to be involved in systemic autoimmunity and cilia genesis in vertebrates. The zebrafish genome expressed two paralogous foxj1 genes, foxj1a and foxj1b. In this study, we demonstrate that down-regulation of either foxj1a or foxj1b by injecting antisense morpholino at the one-cell stage results in randomized expression of the early left-right (LR) asymmetric markers lefty2, southpaw, pitx2c and the later internal organ markers tpm4-tv1, cmlc2, cp in zebrafish embryos. Overexpression of foxj1a and foxj1b by injecting synthetic mRNAs also disrupts normal LR asymmetries. These data indicate that the two foxj1 genes are required for normal laterality development in zebrafish embryos. In contrast to foxj1b knockdown exclusively in dorsal forerunner cells (DFCs) that has little effect on laterality, foxj1a knockdown in DFCs randomizes the LR patterns of the markers. Thus, foxj1a regulates asymmetric development through DFCs in a cell-autonomous fashion but foxj1b functions indirectly.

New insights into the pathogenesis of serous ovarian cancer and its clinical impact

There are only a handful of concepts concerning cancer and carcinogenesis that are currently beyond dispute. One such dogma is the adenoma-carcinoma sequence and that a multistep accumulation of genetic alterations is required for transformation from a benign to a neoplastic tissue. The inevitable derivative of this dogma is that every invasive carcinoma is in fact a missed intraepithelial tumor, and furthermore, a late evolutionary stage in the sequence of development from a precursor lesion. Until fairly recently, high-grade serous ovarian carcinoma seemed to be one of the only known deviants of these concepts. In this article, we discuss the emergence of the fallopian tube fimbria as a field of origin for high-grade serous carcinomas and present a binary model of ovarian cancer pathogenesis that takes into consideration prior epidemiologic, morphologic, and genetic data. With the rise of the fallopian tube secretory epithelial cell as a cell of origin for high-grade pelvic serous carcinomas, the need to develop tools and model systems to characterize the biology and physiology of this cell is recognized.

Feminizing/demasculinizing effects of polychlorinated biphenyls on the secondary sexual development of Xenopus laevis

We have previously demonstrated that polychlorinated biphenyls (PCBs) have caused phenotypic feminization/demasculinization of gonadal development in Xenopus laevis. Whether PCBs affect secondary sexual development has remained unknown. In this study, X. laevis tadpoles were exposed to Aroclor1254 and PCB(3) from stage 46/47 (system of Nieuwkoop and Faber) for up to 1 month postmetamorphosis. After 24 months postmetamorphosis, the degree of secondary sexual development was examined. Male oviducts were observed in some of the PCB-exposed male frogs, but not in control males. These male oviducts had not completely developed in histological structure when compared with mature female oviducts. Larynx weight and width of PCB-exposed males were significantly less than those of control males. Laryngeal histology showed that PCBs inhibited cartilaginous and muscular development of male frogs, i.e. elastic cartilages had not completely developed and laryngeal muscle fibers were smaller. In a further study on adult male frogs, a decrease in serum testosterone level was found in PCB-exposed frogs compared with controls, but serum estradiol level was not significantly affected. Our study suggests that PCBs can cause phenotypic feminization/demasculinization of male genital ducts and larynges, and these effects may, in part, result from the decrease in serum testosterone level in X. laevis.

Imaging and examination strategies of normal male and female sex development and anatomy

Over recent years a variety of new details on the developmental biology of sexual differentiation has been discovered. Moreover, important advances have been made in imaging and examination strategies for urogenital organs, and these have added new knowledge to our understanding of the 'normal' anatomy of the sexes. Both aspects contribute to the comprehension of phenotypic sex development, but they are not commonly presented in the same context. This will be attempted in this chapter, which aims to link discoveries in developmental biology to anatomical details shown by modern examination techniques. A review of the literature concerning the link between sexual development and imaging of urogenital organs was performed. Genes, proteins and pathways related to sexual differentiation were related to some organotypic features revealed by clinical examination techniques. Early 'organotypic' patterns can be identified in prostatic, urethral and genital development and followed into postnatal life. New imaging and endoscopy techniques allow for detailed descriptive anatomical studies, hopefully resulting in a broader understanding of sex development and a better genotype-phenotype correlation in defined disorders. Clinical description relying on imaging techniques should be related to knowledge of the genetic and endocrine factors influencing sex development in a specific and stepwise manner.

Ciliated epithelial-specific and regional-specific expression and regulation of the estrogen receptor-beta2 in the fallopian tubes of immature rats: a possible mechanism for estrogen-mediated transport process in vivo

Several ERbeta isoforms have been identified in human and rodent tissues, but it is unclear whether each isoform has distinctly different cellular targeting characteristics and physiological functions. We have investigated the intracellular localization and regulatory patterns for ERbeta isoforms in rat fallopian tubes. Western blot analysis reveals that two ERbeta isoforms corresponding to ERbeta1 and ERbeta2 are expressed in rat fallopian tubes. However, ERbeta2 is the predominant form of ERbeta in this tissue. High-resolution confocal imaging and immunohistochemical analysis provide ample evidence that ERbeta expression is limited almost exclusively to the ciliated epithelial cells, in contrast to ERalpha, which is widely distributed. Furthermore, within the ciliated epithelial cells, ERbeta is colocalized with beta-tubulin IV at stem portion of the cilia. We show that ERbeta2 protein expression is tightly regulated by E(2) or DPN in a time-dependent manner without changes in ERbeta1 expression. These estrogenic effects are inhibited by an ER antagonist, ICI 182,780. In addition, significant alteration of ERbeta immunoreactivity is detected only histologically in the ampullary region. Since the cilia are considered an essential determinant of tubal transport, we further demonstrate that E(2)- or DPN-induced ERbeta2 activation is associated with alterations in tubal protein expression crucial for the regulation of calcium-dependent ciliary beating. Given the coordinated regulation and interaction of ER and progesterone receptor in the cilia, we hypothesize that tubal ERbeta2 may facilitate the estrogen-mediated transport process by processing protein-protein interaction under physiological and/or pathological conditions. We show for the first time that a previously unrecognized localization of ERbeta isoform in rat fallopian tubes can combine with estrogen to individually control the expression of ER beta-isoforms in normal target tissues.

Experimental endocrine therapies promote epithelial cytodifferentiation and ciliogenesis in the gerbil female prostate

The incidence of ciliated cells in the prostate gland of the female gerbil (Meriones unguiculatus) is uncommon and apparently becomes more frequent during androgen (testosterone cypionate) and anti-estrogen (letrozole) endocrine therapies. To evaluate the effects of such drug therapies on the induction of ciliogenesis in the glandular epithelium of female prostate glands, adult female gerbils aged 90 days were treated for 14 days with testosterone and letrozole after which their prostate glands were removed for histological, ultrastructural, and serological analyses. The cytodifferentiation of the ciliated phenotype in the alveolar epithelium became more frequent after both the testosterone and the letrozole treatments. The ciliogenesis phenomenon of the epithelial cells in the prostate gland of female gerbils thus appears to be induced by variations in the increase of androgen levels.

Identification of single nucleotide polymorphisms in FOXJ1 and their association with allergic rhinitis

Forkhead-box J1 (FOXJ1) is a presumed transcription factor that can suppress T cell activity, at least partially, through the repression of NFkappaB activity. Thus, dysregulation of FOXJ1 is thought to be associated with autoimmune diseases and/or other inflammatory diseases. To investigate the association between single nucleotide polymorphisms (SNPs) of human FOXJ1 and allergic rhinitis, we scanned the whole human FOXJ1 gene, including the promoter region, by direct sequencing of DNA from 32 individuals. We identified seven SNPs, three of which (g.-460C>T, g.1805G>T, and g.3375G>C) were chosen for large sample size genotyping (n=713), and to assess the genotype frequencies of these SNPs between controls and allergic rhinitis patients. We also investigated the relationships of each genotype with serum total IgE levels in allergic rhinitis patients, and compared the frequencies of haplotypes constructed by these SNPs between the two groups. Our results suggest that the SNPs g.-460C>T, g.1805G>T and g.3375G>C in the human FOXJ1 gene might be associated with susceptibility to allergic rhinitis (P=0.0184, 0.0076, and 0.0143, respectively). The main haplotype, CGG, also revealed a significant association with allergic rhinitis (P=0.000018). However, no significant association was found between serum total IgE levels and the genotypes of these polymorphisms.

The mouse forkhead gene Foxc1 is required for primordial germ cell migration and antral follicle development

Foxc1 encodes a forkhead/winged helix transcription factor expressed in many embryonic tissues. Previous studies have investigated defects in the urogenital system of Foxc1 null mutants, but the mechanisms underlying the abnormal development of the gonad have not been explored. From earliest stages, the mutant ovaries are smaller than normal, with fewer germ cells and disorganized somatic issue. No bursa membrane is formed, and the oviduct remains uncoiled. Although germ cells are specified correctly, many of them do not migrate to the gonadal ridge, remaining trapped in the hindgut. Consequently, the number initially reaching the gonad is less than 25% of normal. Once in the ovary, germ cells proliferate normally, but the supporting somatic cells are not organized correctly. Since mutant embryos die at birth, further development was followed in ovaries grafted underneath the kidney capsule of ovariectomized females. Transplanted ovaries display normal folliculogenesis up to preantral stages. However, no follicles develop beyond early antral stages. Mutant follicles are often polyovulatory and have disrupted theca and granulosa cell layers. We conclude that alongside its previously known roles in kidney, cardiovascular and eye development, Foxc1 has essential functions during at least two stages of gonad development-germ cell migration and folliculogenesis.

SEX STEROID HORMONE RECEPTORS IN THE DEVELOPING FEMALE REPRODUCTIVE TRACT OF LABORATORY RODENTS

Many chemicals released into the environment potentially disrupt the endocrine system in wildlife and humans. Some of these chemicals exhibit estrogenic activity by binding to the estrogen receptors. The developing organism is particularly sensitive to estrogenic chemicals during the critical period in which the induction of long-term changes and persistent molecular alterations in female reproductive tracts occur. Perinatal mouse and rat models can be utilized as indicators for determining the consequences of exposure to exogenous estrogenic agents, including possible xenoestrogens or environmental endocrine disruptors. Estrogen receptors (ER) and estrogen responsive genes, therefore, need to be identified in order to understand the molecular basis of estrogenic actions. Recent identifications of ER subtypes and isoforms make understanding target organ responses to these estrogenic chemicals even more difficult. Indeed, many reports suggest that these chemicals do affect the reproductive and developmental processes of female laboratory rodents that had been perinatally exposed, and that interactions between sex steroid hormone receptors occur. Much information concerning the expression of sex steroid receptors in rodents has been reported concerning the normal development of the Müllerian duct. Thus, accumulated information on the expression of ER subtypes and isoforms as well as that of progesterone and androgen receptors in laboratory rodents is herein reviewed, in addition to the presentation of our own data.