The importance of stroma in morphogenesis and functional activity of urogenital epithelium

Histological Features of Neovaginal Epithelium after Vaginoplasty in Mayer-Rokitansky-Küster-Hauser Syndrome

OBJECTIVE

To analyze the features of the epithelia coating neovaginas after vaginoplasty in women affected by Mayer-Rokitansky-Küster-Hauser syndrome STUDY DESIGN: We conducted a retrospective analysis of prospectively collected data. Women affected by Rokitansky syndrome who underwent neovaginal biopsy after vaginoplasty (McIndoe surgery, intestinal vaginoplasty, Vecchietti surgery, and Davydov surgery) were included. Macroscopic mucosal features were assessed through clinical examination and the Schilling test. Each biopsy specimen was prepared for examination by light microscopy and in some cases by scanning electron microscopy (SEM).

RESULTS

Thirty-six patients (4 McIndoe, 2 intestinal vaginoplasty, 14 Vecchietti, and 16 Davydov) were included. All biopsies were performed without complications. In McIndoe's neovaginas, the mucosal microscopic features were similar to normal skin, with large areas of preserved epithelium, heterogeneous presence of dermal papillae, and superficial keratinization. The characteristics of the intestinal neovagina's surface were similar to those of a sigmoid colon, with well-shaped glands, cylindrical cells, and a secreting mucosa. In Vecchietti neovaginas, the surface the epithelium was flat and multilayered, highly similar to that of a normal vagina, with the presence of glycogen and superficial desquamation. On medium SEM magnification evaluation, the epithelium presented flattened polygonal cells. Finally, in Davydov neovaginas, none of the specimens had persistent mesothelial elements. The squamous neo-epithelium had regular aspects of differentiation with the presence of glycogen. At greater SEM magnification, microridges were evident, with a regular distribution.

CONCLUSION

Each different technique of vaginoplasty leads to unique histological and structural features of the neovagina's mucosa. Knowledge of these elements must be the basis for the choice of the most appropriate intervention.

The architecture of clonal expansions in morphologically normal tissue from cancerous and non-cancerous prostates

BACKGROUND

Up to 80% of cases of prostate cancer present with multifocal independent tumour lesions leading to the concept of a field effect present in the normal prostate predisposing to cancer development. In the present study we applied Whole Genome DNA Sequencing (WGS) to a group of morphologically normal tissue (n = 51), including benign prostatic hyperplasia (BPH) and non-BPH samples, from men with and men without prostate cancer. We assess whether the observed genetic changes in morphologically normal tissue are linked to the development of cancer in the prostate.

RESULTS

Single nucleotide variants (P = 7.0 × 10-03, Wilcoxon rank sum test) and small insertions and deletions (indels, P = 8.7 × 10-06) were significantly higher in morphologically normal samples, including BPH, from men with prostate cancer compared to those without. The presence of subclonal expansions under selective pressure, supported by a high level of mutations, were significantly associated with samples from men with prostate cancer (P = 0.035, Fisher exact test). The clonal cell fraction of normal clones was always higher than the proportion of the prostate estimated as epithelial (P = 5.94 × 10-05, paired Wilcoxon signed rank test) which, along with analysis of primary fibroblasts prepared from BPH specimens, suggests a stromal origin. Constructed phylogenies revealed lineages associated with benign tissue that were completely distinct from adjacent tumour clones, but a common lineage between BPH and non-BPH morphologically normal tissues was often observed. Compared to tumours, normal samples have significantly less single nucleotide variants (P = 3.72 × 10-09, paired Wilcoxon signed rank test), have very few rearrangements and a complete lack of copy number alterations.

CONCLUSIONS

Cells within regions of morphologically normal tissue (both BPH and non-BPH) can expand under selective pressure by mechanisms that are distinct from those occurring in adjacent cancer, but that are allied to the presence of cancer. Expansions, which are probably stromal in origin, are characterised by lack of recurrent driver mutations, by almost complete absence of structural variants/copy number alterations, and mutational processes similar to malignant tissue. Our findings have implications for treatment (focal therapy) and early detection approaches.

The damage effect of heat stress and psychological stress combined exposure on uterus in female rats

AIMS

Explore the effects of heat stress and psychological stress combined exposure on the uterus and its underlying mechanisms.

MAIN METHODS

Sixty female Sprague-Dawley rats were randomly assigned to four groups: control group, psychological stress group, high ambient temperature group, and high ambient temperature combined with psychological stress group. All treatments were administered for two weeks. During this period, the estrous cycle, body weights and rectal temperature were measured regularly. Then, ovarian weight coefficient, serum estradiol (E₂) and progesterone (P) concentration, uterine histomorphological alterations, levels of tumor necrosis factor alpha (TNF-α), malondialdehyde (MDA) and superoxide dismutase (SOD), and the expressions of ovarian hormone receptors, leukemia inhibitory factor (LIF) and its receptor, homeobox gene A10 (HoxA10), Wnt5a, Wnt7a, β-catenin, and P-β-catenin^Y142 in the uterus and endometrium were detected.

KEY FINDINGS

High temperature combined with psychological stress lead to body weight, body temperature, ovarian hormones and estrus cycle disorder, uterine gland ducts expansion and endometrial thickness reduction, and the decreased expression of endometrial receptivity markers (LIF and HoxA10). Further, disturbed expression of E₂ and P receptors in endometrium, elevated MDA and TNF-α levels, and decreased Wnt5a, Wnt7a and P-β-catenin^Y142 content were found. Our data suggested that co-exposure to high temperature and psychological stress could aggravate uterine damage probably by inducing ovarian hormonal disorder and the subsequent oxidative stress and inflammation, and reduce the endometrial function through suppressing Wnt signaling.

SIGNIFICANCE

This will provide the scientific basis for improving female reproductive health, and preventing and treating reproductive disorders.

Heparan sulfate inhibits transforming growth factor β signaling and functions in cis and in trans to regulate prostate stem/progenitor cell activities

Prostate stem/progenitor cells (PrSCs) are responsible for adult prostate tissue homeostasis and regeneration. However, the related regulatory mechanisms are not completely understood. In this study, we examined the role of heparan sulfate (HS) in PrSC self-renewal and prostate regeneration. Using an in vitro prostate sphere formation assay, we found that deletion of the glycosyltransferase exostosin 1 (Ext1) abolished HS expression in PrSCs and disrupted their ability to self-renew. In associated studies, we observed that HS loss inhibited p63 and CK5 expression, reduced the number of p63+- or CK5+-expressing stem/progenitor cells, elevated CK8+ expression and the number of differentiated CK8+ luminal cells and arrested the spheroid cells in the G1/G0 phase of cell cycle. Mechanistically, HS expressed by PrSCs (in cis) or by neighboring cells (in trans) could maintain sphere formation. Furthermore, HS deficiency upregulated transforming growth factor β (TGFβ) signaling and inhibiting TGFβ signaling partially restored the sphere-formation activity of the HS-deficient PrSCs. In an in vivo prostate regeneration assay, simultaneous loss of HS in both epithelial cell and stromal cell compartments attenuated prostate tissue regeneration, whereas the retention of HS expression in either of the two cellular compartments was sufficient to sustain prostate tissue regeneration. We conclude that HS preserves self-renewal of adult PrSCs by inhibiting TGFβ signaling and functions both in cis and in trans to maintain prostate homeostasis and to support prostate regeneration.

New frontiers of developmental endocrinology opened by researchers connecting irreversible effects of sex hormones on developing organs

In the early 1960's, at Professor Bern's laboratory, University of California, Berkeley) in the US, Takasugi discovered ovary-independent, persistent vaginal changes in mice exposed neonatally to estrogen, which resulted in vaginal cancer later in life. Reproductive abnormalities in rodents were reported as a result of perinatal exposure to various estrogenic chemicals. Ten years later, vaginal cancers were reported in young women exposed in utero to the synthetic estrogen diethylstilbestrol (DES) and this has been called the "DES syndrome". The developing organism is particularly sensitive to developmental exposure to estrogens inducing long-term changes in various organs including the reproductive organs. The molecular mechanism underlying the persistent vaginal changes induced by perinatal estrogen exposure was partly demonstrated. Persistent phosphorylation and sustained expression of EGF-like growth factors, lead to estrogen receptor α (ESR1) activation, and then persistent vaginal epithelial cell proliferation. Agents which are weakly estrogenic by postnatal criteria may have major developmental effects, especially during a critical perinatal period. The present review outlines various studies conducted by four generations of investigators all under the influence of Prof. Bern. The studies include reports of persistent changes induced by neonatal androgen exposure, analyses of estrogen responsive genes, factors determining epithelial differentiation in the Müllerian duct, ESR and growth factor signaling, and polyovular follicles in mammals. This review is then expanded to the studies on the effects of environmental estrogens on wildlife and endocrine disruption in Daphnids.

Mice lacking uterine enhancer of zeste homolog 2 have transcriptomic changes associated with uterine epithelial proliferation

Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase that suppresses gene expression. Previously, we developed a conditional null model where EZH2 is knocked out in uterus. Deletion of uterine EZH2 increased proliferation of luminal and glandular epithelial cells. Herein, we used RNA-Seq in wild-type (WT) and EZH2 conditional knockout (Ezh2cKO) uteri to obtain mechanistic insights into the gene expression changes that underpin the pathogenesis observed in these mice. Ovariectomized adult Ezh2cKO mice were treated with vehicle (V) or 17β-estradiol (E2; 1 ng/g). Uteri were collected at postnatal day (PND) 75 for RNA-Seq or immunostaining for epithelial proliferation. Weighted gene coexpression network analysis was used to link uterine gene expression patterns and epithelial proliferation. In V-treated mice, 88 transcripts were differentially expressed (DEG) in Ezh2cKO mice, and Bmp5, Crabp2, Lgr5, and Sprr2f were upregulated. E2 treatment resulted in 40 DEG with Krt5, Krt15, Olig3, Crabp1, and Serpinb7 upregulated in Ezh2cKO compared with control mice. Transcript analysis relative to proliferation rates revealed two module eigengenes correlated with epithelial proliferation in WT V vs. Ezh2cKO V and WT E2 vs. Ezh2cKO E2 mice, with a positive relationship in the former and inverse in the latter. Notably, the ESR1, Wnt, and Hippo signaling pathways were among those functionally enriched in Ezh2cKO females. Current results reveal unique gene expression patterns in Ezh2cKO uterus and provide insight into how loss of this critical epigenetic regulator assumingly contributes to uterine abnormalities.

Development and Function of Uterine Glands in Domestic Animals

All mammalian uteri contain glands that synthesize or transport and secrete substances into the uterine lumen. Uterine gland development, or adenogenesis, is uniquely a postnatal event in sheep and pigs and involves differentiation of glandular epithelium from luminal epithelium, followed by invagination and coiling morphogenesis throughout the stroma. Intrinsic transcription factors and extrinsic factors from the ovary and pituitary as well as the mammary gland (lactocrine) regulate uterine adenogenesis. Recurrent pregnancy loss is observed in the ovine uterine gland knockout sheep, providing unequivocal evidence that glands and their products are essential for fertility. Uterine gland hyperplasia and hypertrophy during pregnancy are controlled by sequential actions of hormones from the ovary and/or pituitary as well as the placenta. Gland-derived histotroph is transported by placental areolae for fetal growth. Increased knowledge of uterine gland biology is expected to improve pregnancy outcomes, as well as the health and productivity of mothers and their offspring.

Role of estrogen and RAS signaling in repeated implantation failure

In humans, hormonal regulation is crucial for the preparation of uterine environment leading to either successful implantation or menstrual cycle. Estrogen is a pivotal female steroid hormone that regulates the uterine dynamics along with progesterone in the estrous and menstrual cycles in humans. Estrogen signals act via nuclear estrogen receptor or membrane-bound receptor. The membrane-bound estrogen receptor plays a crucial role in the rapid response of estrogen in the uterine epithelium. Recently, RASD1 has received attention as a novel signal transducer of estrogen in various systems including female reproductive organs. In this review, we discuss the regulation of estrogen and RASD1 signaling in the uterus and also provide insights into RAS as a novel signaling molecule in repeated implantation failure.

Estrogen is essential but not sufficient to induce endometriosis

Endometriosis is a common gynaecological disorder of unknown aetiology. Among the several factors, estrogen has been implicated as a causative factor in endometriosis. In the present study using mouse model, we assessed the role of estrogen in the initial implantation and growth of endometrium in ectopic locations. Uterine tissues from green fluorescent protein (GFP) mice were transplanted in to the peritoneum of wild type mice in presence and absence of estrogen. As compared to untreated controls, the implantation of uterine tissue at ectopic locations was higher when estrogen was administered to both host and donor animals. However, this effect was not sustained as lesions regressed within 14 days of treatment. Irrespective of the treatment, peritoneal adipose was the most preferred site of lesion establishment. The lesions did not have typical features of the endometriosis (presence of glands and stroma) even after estrogen treatment and the ectopic tissue underwent regression by apoptosis irrespective of treatment. Since estrogen promotes implantation of endometrial tissue to ectopic locations but failure of these ectopic lesions to grow and sustain even in high estrogenic environment we propose that estrogen is necessary but not sufficient to sustain endometriosis.

Prostate cancer xenografts and hormone induced prostate carcinogenesis

Despite the advancement of transgenic and gene knockout animal models in the prostate cancer research, there is still a need for utilizing xenograft models. Xenografts can be grown in multiple sites/organs within immunocompromised animals such as mice and rats. Although prostate xenografts have been derived from many species, human cells and tissues are the most commonly used due to their potential clinical significance. Xenograft models that progress from one state or stage to another are commonly used to address important scientific questions including malignant transformation, metastatic spread, and castration resistance. Utilization of xenografts are commonly being used to assess the biology and genetics of prostate cancer, as well as, for therapeutic benefit. In addition to models for the study of prostate cancer, xenografts are also utilized as a tool in precision medicine where patient derived xenografts (PDX) can be grown in multiple animals and assessed for therapeutic efficacy. The popularity of such xenograft models and PDXs have led to availability of these resources through public and commercial institutions. In this review, we describe both traditional and emerging models of prostate cancer and their potential uses. Further development of current models and introduction of new models will likely provide new insights and better understanding of prostatic carcinogenesis and progression.

Targeting phenotypic heterogeneity in benign prostatic hyperplasia

Benign prostatic hyperplasia and associated lower urinary tract symptoms remain difficult to treat medically, resulting in hundreds of thousands of surgeries performed annually in elderly males. New therapies have not improved clinical outcomes since alpha blockers and 5 alpha reductase inhibitors were introduced in the 1990s. An underappreciated confounder to identifying novel targets is pathological heterogeneity. Individual patients display unique phenotypes, composed of distinct cell types. We have yet to develop a cellular or molecular understanding of these unique phenotypes, which has led to failure in developing targeted therapies for personalized medicine. This review covers the strategic experimental approach to unraveling the cellular pathogenesis of discrete BPH phenotypes and discusses how to incorporate these findings into the clinic to improve outcomes.

Progress made in the use of animal models for the study of high-risk, nonmuscle invasive bladder cancer

PURPOSE OF REVIEW

High-risk, nonmuscle invasive bladder cancer (HR-NMIBC) represents a costly and difficult-to-treat disease, the molecular pathogenesis of which has a limited understanding. Most preclinical models for the study of bladder cancer are more appropriate for the study of advanced disease. However, recent key advances in preclinical animal models places us at an opportune position to better understand HR-NMIBC.

RECENT FINDINGS

Discoveries in the basic sciences allow us to better understand tumor biology when building models of bladder cancer. Of note, a key study on urothelial progenitor cells recently highlighted an important role for Sonic hedgehog-positive cells and retinoid signaling that is essential for urothelial development and regeneration. In the translational realm, transgenic mouse models continue to be used, with a recent interest in the role of Wnt/beta-catenin in urothelial carcinomas. Tissue recombination models are also being increasingly utilized to better recreate the tissue microenvironment and better understand stromal-epithelial interactions and the impact of genetic alterations on tissue differentiation. Lastly, the avatar mouse systems, which involve direct xenotransplantation of human tumor specimens into immunocompromised mice, represent an additional approach to study cancer characteristics in a preserved tissue context.

SUMMARY

With molecular alterations remaining an unclear area of our understanding of HR-NMIBC, preclinical models of bladder cancer serve as essential tools to discover specific genetic compromises in disease pathogenesis and the therapeutics to treat them.

Estrogen mediated epithelial proliferation in the uterus is directed by stromal Fgf10 and Bmp8a

To define endometrial stromal-derived paracrine mediators that participate in estradiol-17β (E2)-induced epithelial proliferation, microarray analysis of gene expression was carried out in mouse uterine epithelial-stromal co-culture systems under the condition of E2 or vehicle (control). Our results demonstrated gene alteration by E2: in epithelial cells, we found up-regulation of 119 genes and down-regulation of 28 genes, while in stroma cells we found up-regulation of 144 genes and down-regulation of 184 genes. A functional enrichment analysis of the upregulated epithelial genes implicated them for proliferation, while upregulated stromal genes were associated with extracellular functions. Quantitative RT-PCR and in situ hybridization results confirmed differential gene expression in both cell cultures and ovariectomized uteri after the above treatments. Based on our identification of stromal secretory factors, we found evidence that suppression by siRNA specifically for Bmp8a and/or Fgf10 in the stromal layer caused significant inhibition of proliferation by E2 in the co-culture system, suggesting Bmp8a and Fgf10 act as paracrine mediators during E2-dependent control of uterine proliferation. The localization of receptors and receptor activation signaling in epithelial cells in both the co-culture system and uteri was consistent with their involvement in ligand-receptor signaling. Interestingly, loss of Bmp8a or Fgf10 also caused abrogation of E2-regulated epithelial receptor signaling in co-culture systems, suggesting that stroma-derived Fgf10 and Bmp8a are responsible for epithelial communication. Overall, stromal Fgf10 and Bmp8a serve as potential paracrine factors for E2-dependent regulation of epithelial proliferation in the uterus.

Next generation patient-derived prostate cancer xenograft models

There is a critical need for more effective therapeutic approaches for prostate cancer. Research in this area, however, has been seriously hampered by a lack of clinically relevant, experimental in vivo models of the disease. This review particularly focuses on the development of prostate cancer xenograft models based on subrenal capsule grafting of patients’ tumor tissue into nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. This technique allows successful development of transplantable, patient-derived cancer tissue xenograft lines not only from aggressive metastatic, but also from localized prostate cancer tissues. The xenografts have been found to retain key biological properties of the original malignancies, including histopathological and molecular characteristics, tumor heterogeneity, response to androgen ablation and metastatic ability. As such, they are highly clinically relevant and provide valuable tools for studies of prostate cancer progression at cellular and molecular levels, drug screening for personalized cancer therapy and preclinical drug efficacy testing; especially when a panel of models is used to cover a broader spectrum of the disease. These xenograft models could therefore be viewed as next-generation models of prostate cancer.

Current concepts and significance of estrogen receptor β in prostate cancer

An increasing amount of evidence points at important roles for estrogen receptors in prostate carcinogenesis and progression. Of the two estrogen receptors, estrogen receptor β is the most prominent within the prostate gland. Although there is much yet to be known, the findings from the discovery of the receptor in 1996 until now point at a role of the receptor in maintaining differentiation and reducing cellular proliferation in the prostate. Moreover, estrogen receptor β is the main target for phytoestrogens, perhaps at least partially explaining the difference in incidence of prostate cancer in the Western world compared to Asia where the intake of soy-based, phytoestrogen-rich food is higher. The tumor suppressive capability of estrogen receptor β makes it a promising drug target for the treatment and prevention of prostate cancer. This review will focus on different aspects of estrogen receptor signaling and prostate cancer.

Progesterone inhibits uterine gland development in the neonatal mouse uterus

Uterine glands and their secretions are required for conceptus (embryo/fetus and associated placenta) survival and development. In most mammals, uterine gland morphogenesis or adenogenesis is a uniquely postnatal event; however, little is known about the mechanisms governing the developmental event. In sheep, progestin treatment of neonatal ewes permanently ablated differentiation of the endometrial glands. Similarly, progesterone (P4) inhibits adenogenesis in neonatal mouse uterus. Thus, P4 can be used as a tool to discover mechanisms regulating endometrial adenogenesis. Female pups were treated with sesame vehicle alone as a control or P4 from Postnatal Day 2 (PD 2) to PD 10, and reproductive tracts were examined on PD 5, 10, or 20. Endometrial glands were fully developed in control mice by PD 20 but not in P4-treated mice. All other uterine cell types appeared normal. Treatment with P4 stimulated proliferation of the stroma but suppressed proliferation of the luminal epithelium. Microarray analysis revealed that expression of genes were reduced (Car2, Fgf7, Fgfr2, Foxa2, Fzd10, Met, Mmp7, Msx1, Msx2, Wnt4, Wnt7a, Wnt16) and increased (Hgf, Ihh, Wnt11) by P4 in the neonatal uterus. These results support the idea that P4 inhibits endometrial adenogenesis in the developing neonatal uterus by altering expression of morphoregulatory genes and consequently disrupting normal patterns of cell proliferation and development.

Loss of the urothelial differentiation marker FOXA1 is associated with high grade, late stage bladder cancer and increased tumor proliferation

Approximately 50% of patients with muscle-invasive bladder cancer (MIBC) develop metastatic disease, which is almost invariably lethal. However, our understanding of pathways that drive aggressive behavior of MIBC is incomplete. Members of the FOXA subfamily of transcription factors are implicated in normal urogenital development and urologic malignancies. FOXA proteins are implicated in normal urothelial differentiation, but their role in bladder cancer is unknown. We examined FOXA expression in commonly used in vitro models of bladder cancer and in human bladder cancer specimens, and used a novel in vivo tissue recombination system to determine the functional significance of FOXA1 expression in bladder cancer. Logistic regression analysis showed decreased FOXA1 expression is associated with increasing tumor stage (p<0.001), and loss of FOXA1 is associated with high histologic grade (p<0.001). Also, we found that bladder urothelium that has undergone keratinizing squamous metaplasia, a precursor to the development of squamous cell carcinoma (SCC) exhibited loss of FOXA1 expression. Furthermore, 81% of cases of SCC of the bladder were negative for FOXA1 staining compared to only 40% of urothelial cell carcinomas. In addition, we showed that a subpopulation of FOXA1 negative urothelial tumor cells are highly proliferative. Knockdown of FOXA1 in RT4 bladder cancer cells resulted in increased expression of UPK1B, UPK2, UPK3A, and UPK3B, decreased E-cadherin expression and significantly increased cell proliferation, while overexpression of FOXA1 in T24 cells increased E-cadherin expression and significantly decreased cell growth and invasion. In vivo recombination of bladder cancer cells engineered to exhibit reduced FOXA1 expression with embryonic rat bladder mesenchyme and subsequent renal capsule engraftment resulted in enhanced tumor proliferation. These findings provide the first evidence linking loss of FOXA1 expression with histological subtypes of MIBC and urothelial cell proliferation, and suggest an important role for FOXA1 in the malignant phenotype of MIBC.

Comparative developmental biology of the uterus: insights into mechanisms and developmental disruption

The uterus is an essential organ for reproduction in mammals that derives from the Müllerian duct. Despite the importance of the uterus for the fertility and health of women and their offspring, relatively little is known about the hormonal, cellular and molecular mechanisms that regulate development of the Müllerian duct and uterus. This review aims to summarize the hormonal, cellular and molecular mechanisms and pathways governing development of the Müllerian duct and uterus as well as highlight developmental programming effects of endocrine disruptor compounds. Organogenesis, morphogenesis, and functional differentiation of the uterus are complex, multifactorial processes. Disruption of uterine development in the fetus and neonate by genetic defects and exposure to endocrine disruptor compounds can cause infertility and cancer in the adult and their offspring via developmental programming. Clear conservation of some factors and pathways are observed between species; therefore, comparative biology is useful to identify candidate genes and pathways underlying congenital abnormalities in humans.

Androgen hormone action in prostatic carcinogenesis: stromal androgen receptors mediate prostate cancer progression, malignant transformation and metastasis

It has been postulated that prostatic carcinogenesis is androgen dependent and that androgens mediate their effects primarily through epithelial cells; however, definitive proof of androgen hormone action in prostate cancer (PRCA) progression is lacking. Here we demonstrate through genetic loss of function experiments that PRCA progression is androgen dependent and that androgen dependency occurs via prostatic stromal androgen receptors (AR) but not epithelial AR. Utilizing tissue recombination models of prostatic carcinogenesis, loss of AR function was evaluated by surgical castration or genetic deletion. Loss of AR function prevented prostatic carcinogenesis, malignant transformation and metastasis. Tissue-specific evaluation of androgen hormone action demonstrated that epithelial AR was not necessary for PRCA progression, whereas stromal AR was essential for PRCA progression, malignant transformation and metastasis. Stromal AR was not necessary for prostatic maintenance, suggesting that the lack of cancer progression due to stromal AR deletion was not related to altered prostatic homeostasis. Gene expression analysis identified numerous androgen-regulated stromal factors. Four candidate stromal AR-regulated genes were secreted growth factors: fibroblast growth factors-2, -7, -10 and hepatocyte growth factor which were significantly affected by androgens and anti-androgens in stromal cells grown in vitro. These data support the concept that androgens are necessary for PRCA progression and that the androgen-regulated stromal microenvironment is essential to carcinogenesis, malignant transformation and metastasis and may serve as a potential target in the prevention of PRCA.

LC/LC-MS/MS of an innovative prostate human epithelial cancer (PHEC) in vitro model system

This work describes the proteomic characterization of a novel in vitro prostate cancer model system, the clonal prostatic human epithelial cancer (PHEC) cell lines. The model is composed of three cell lines representing the three progressive cancer states found in vivo: non-tumorigenic, tumorigenic, and metastatic. The cell lines were evaluated for differential protein expression between states using two dimensional liquid:liquid chromatographic separation followed by mass spectral identification. The proteins from cellular extracts were first separated using liquid:liquid primary separation based on their isoelectric points and hydrophobicity. The resulting peptide fractions were applied to liquid chromatography-mass spectrometry (LC-MS) separation for mass determination and protein identification based on Mascot database inquiry. Over 200 proteins that change expression over the course of progression of this in vitro prostate cancer model were discovered during the comparative analysis of the three cell lines. The importance of these proteins on prostate cancer progression remains to be elucidated with further characterizations. The combination of the two dimensional liquid:liquid separation and mass spectral identifications was used to successfully analyze differential protein expression between multiple cell lines.

The diverse and contrasting effects of using human prostate cancer cell lines to study androgen receptor roles in prostate cancer

The androgen receptor (AR) plays an important role in the development and progression of prostate cancer (PCa). Androgen deprivation therapy is initially effective in blocking tumor growth, but it eventually leads to the hormone-refractory state. The detailed mechanisms of the conversion from androgen dependence to androgen independence remain unclear. Several PCa cell lines were established to study the role of AR in PCa, but the results were often inconsistent or contrasting in different cell lines, or in the same cell line grown under different conditions. The cellular and molecular alteration of epithelial cells and their microenvironments are complicated, and it is difficult to use a single cell line to address this important issue and also to study the pathophysiological effects of AR. In this paper, we summarize the different effects of AR on multiple cell lines and show the disadvantages of using a single human PCa cell line to study AR effects on PCa. We also discuss the advantages of widely used epithelium-stroma co-culture systems, xenograft mouse models, and genetically engineered PCa mouse models. The combination of in vitro cell line studies and in vivo mouse models might lead to more credible results and better strategies for the study of AR roles in PCa.

Steroid hormones and carcinogenesis of the prostate: the role of estrogens

Androgens have long been known to be the major sex hormones that target the prostate during development, maturation, and carcinogenesis. It is now apparent that estrogens, both those synthesized by the body as well as those from our environment, also target the prostate during all stages of development. Little is known about the mechanisms involved in estrogen stimulation of carcinogenesis and less is known about how to prevent or treat prostate cancer through estrogenic pathways. To better understand how estrogens mediate their carcinogenic effects, the respective roles of estrogen receptor (ER)-alpha and ER-beta must be elucidated in the epithelial and stromal cells that constitute the prostate. Lastly, the significance of ER signaling during various ontogenic periods must be determined. Answers to these questions will further our understanding of the mechanisms of estrogen/ER signaling and will serve as a basis for chemopreventive and/or chemotherapeutic strategies for prostate cancer.

Neonatal exposure to progesterone and estradiol alters uterine morphology and luminal protein content in adult beef heifers

Exposure of the developing urogenital tract to steroids can affect structure and function of adult tissues and compromise reproductive performance. This study was conducted to determine 1) if exposure of neonatal heifer calves to progesterone (P) and estradiol benzoate (E), delivered from a commercial growth-promoting implant, would affect adult uterine morphology or uterine luminal protein content; and 2) whether such effects would be related to neonatal age at the first exposure. At birth (Day 0), 20 crossbred beef heifers were assigned to 1 of 4 treatment groups (n = 5 per group), defined by age at implant placement. Heifers either received an implant on Days 0, 21 or 45, or served as untreated controls. The heifers were maintained together and slaughtered at 15 mo of age, during the luteal phase of an induced estrous cycle, when reproductive tracts and blood samples were obtained. Peripheral plasma P concentrations were determined by RIA. Uterocervical wet weights were recorded, and uterine luminal flushings (ULF) were assayed for total protein. Cross-sections of uterine tissues were evaluated histomorphometrically to determine myometrial and endometrial areas and relative endometrial gland density. Treatment did not affect plasma P concentrations (3.2 +/- 0.5 ng/ml). Regardless of age at treatment, neonatal PE exposure reduced uterocervical wet weight by 35% (112.8 < 173.9 +/- 13.9 g; P < 0.01), myometrial area by 23% (125.3 < 162.8 +/- 8.5 mm2; P < 0.02), and endometrial area by 27% (33.3 < 45.4 +/- 2.7 mm2; P < 0.09) compared with the untreated controls. Endometrial gland density was reduced (P < 0.01) by 40% in treated heifers. This effect was related to age at implant placement. Uterine gland density was reduced (P < 0.01) by 65% in heifers treated at birth, while reductions of 22 and 33% were observed for heifers treated on neonatal Day 21 or 45, respectively. Consistently, ULF protein content was lower (P < 0.01) in the treated heifers (2.67 < 4.98 +/-. 72 mg/ULF). Thus, exposure of newborn calves to PE can have profound effects on adult uterine morphology and environment, the extent of which may depend upon the developmental period when exposure occurs. The potential of such alterations to affect reproductive performance in adult beef heifers remains to be investigated.

Paracrine mediators of mouse uterine epithelial cell transepithelial resistance in culture

Epithelial cell integrity at mucosal surfaces provides an effective physical barrier against potential pathogens that threaten reproductive health. We have used polarized epithelial cells from adult mouse uteri to investigate the roles of TNFalpha and TGFbeta, which are produced by uterine epithelial and stromal cells, and hepatocyte growth factor (HGF), produced by uterine stromal cells, in regulating epithelial cell integrity measured as transepithelial electrical resistance (TER). Exposure of epithelial cells to TNFalpha, TGFbeta, and HGF have profound effects on TER that are different from their known actions on TER at other mucosal surfaces. When incubated with TNFalpha, TER increased in a dose-dependent manner. In contrast, when cells were incubated with TGFbeta, TER was markedly but reversibly suppressed. Interestingly, HGF, when placed in the basolateral compartment, increased TER. Based on these findings, we conclude that TNFalpha, TGFbeta and HGF may play regulatory roles in modulating epithelial cell tight junctions. These studies suggest that factors, such as hormone balance, pathogen exposure as well as pregnancy, which affect cytokine and growth factor secretion, influence epithelial cell barrier protection within the female reproductive tract.

The inflammatory and normal transcriptome of mouse bladder detrusor and mucosa

Background

An organ such as the bladder consists of complex, interacting set of tissues and cells. Inflammation has been implicated in every major disease of the bladder, including cancer, interstitial cystitis, and infection. However, scanty is the information about individual detrusor and urothelium transcriptomes in response to inflammation. Here, we used suppression subtractive hybridizations (SSH) to determine bladder tissue- and disease-specific genes and transcriptional regulatory elements (TRE)s. Unique TREs and genes were assembled into putative networks.

Results

It was found that the control bladder mucosa presented regulatory elements driving genes such as myosin light chain phosphatase and calponin 1 that influence the smooth muscle phenotype. In the control detrusor network the Pax-3 TRE was significantly over-represented. During development, the Pax-3 transcription factor (TF) maintains progenitor cells in an undifferentiated state whereas, during inflammation, Pax-3 was suppressed and genes involved in neuronal development (synapsin I) were up-regulated. Therefore, during inflammation, an increased maturation of neural progenitor cells in the muscle may underlie detrusor instability. NF-κB was specifically over-represented in the inflamed mucosa regulatory network. When the inflamed detrusor was compared to control, two major pathways were found, one encoding synapsin I, a neuron-specific phosphoprotein, and the other an important apoptotic protein, siva. In response to LPS-induced inflammation, the liver X receptor was over-represented in both mucosa and detrusor regulatory networks confirming a role for this nuclear receptor in LPS-induced gene expression.

Conclusion

A new approach for understanding bladder muscle-urothelium interaction was developed by assembling SSH, real time PCR, and TRE analysis results into regulatory networks. Interestingly, some of the TREs and their downstream transcripts originally involved in organogenesis and oncogenesis were also activated during inflammation. The latter represents an additional link between inflammation and cancer. The regulatory networks represent key targets for development of novel drugs targeting bladder diseases.

Estrogen disruption of neonatal ovine uterine development: effects on gene expression assessed by suppression subtraction hybridization

Inappropriate exposure of neonatal sheep to estrogen during critical developmental periods inhibits or retards endometrial gland morphogenesis and reduces uterine growth. Studies were conducted to identify mechanisms mediating estrogen disruption of neonatal ovine uterine development by analysis of candidate growth factor systems and using suppression subtraction hybridization (SSH). In study 1, sheep were exposed either to corn oil as a control or to estradiol valerate (EV) from birth to Postnatal Day (PND) 14, which ablated endometrial gland development. Estradiol valerate decreased uterine FGF7 (fibroblast growth factor 7) and MET (hepatocyte growth factor receptor) expression and increased INHBA (inhibin betaA). The SSH identified a number of genes responsive to EV, which included GSTM3 (glutathione S-transferase), IDH1 (cytosolic NADP-isocitrate dehydrogenase), PECI (peroxisomal D(3),D(2)-enoyl-coenzyme A isomerase), OAS1 (2',5'-oligoadenylate 40/46-kDa synthetase), IGFBP3 (insulin-like growth factor-binding protein-3), TEGT (testis-enhanced gene transcript), CXCL10 (interferon-gamma-inducible protein 10), and IGLV (immunoglobulin V). These mRNAs were expressed predominantly in the endometrial epithelia (GSTM3, IDH1, PEC1, OAS1, and TEGT), stroma (IGFBP3), or immune cells (CXCL10 and IGLV). In study 2, effects of estrogen exposure on uterine gene expression were determined during three different critical developmental periods (PNDs 0-14, 14- 28, and 42-56). Estrogen exposure decreased expression of the SSH-identified genes, particularly those from PNDs 0-14. These studies suggest that estrogen disruption of postnatal uterine development involves period-specific effects on expression of genes predominantly in the endometrial epithelium. The SSH-identified, estrogen-disrupted genes represent new candidate regulators of postnatal endometrial adenogenesis.

The IGF system in the neonatal ovine uterus

Postnatal development of the ovine uterus primarily involves uterine gland morphogenesis or adenogenesis. Adenogenesis involves the budding differentiation of the glandular epithelium (GE) from the luminal epithelium (LE) and then GE proliferation and coiling/branching morphogenetic development within the stroma between birth (postnatal day or PND 0) and PND 56. Insulin-like growth factor (IGF)-I and IGF-II mRNAs were previously found to be expressed only in the endometrial stroma, whereas the IGF receptor (IGF-1R) mRNA was most abundant in epithelia and in stroma, suggesting that an intrinsic IGF system regulates postnatal development of the uterus. Given that the biological activities of IGFs are modulated by a family of six IGF binding proteins (IGFBPs) and specific proteases, the objective was to determine the effects of age and estrogen disruption on expression of IGFs, IGFBPs and pregnancy-associated plasma protein A (PAPP-A or IGFBP-4 protease) in the ovine uterus. In Study One, circulating levels of IGF-I and IGF-II in the serum of neonatal ewes did not change between PND 0 and PND 56. Levels of immunoreactive IGF-I, IGF-II and IGF-1R protein were most abundant on the apical surface of the endometrial LE and GE. RT-PCR analyses detected expression of IGFBPs (3, 4, 5 and 6) as well as PAPP-A mRNAs in the uterus, but not IGFBP-1 and IGFBP-2 mRNAs. IGFBP-3 and IGFBP-4 mRNAs were expressed specifically in the endometrial stroma and myometrium and increased after birth. PAPP-A mRNA was expressed specifically in the endometrial stroma and increased after birth. In Study Two, ewes were treated from birth with estradiol-17beta valerate (EV), which reduces uterine growth and inhibits endometrial adenogenesis. On PNDs 14 and 56, IGFBP-3 mRNA was decreased in the uterus of EV-treated ewes, but IGF-1R and IGFBP-4 mRNAs were not affected. PAPP-A mRNA was increased by EV treatment on PND 14, but decreased on PND 56. These results support the hypothesis that an intrinsic IGF system in the uterus regulates epithelial-stromal interactions important for postnatal uterine growth and endometrial gland morphogenesis in the sheep.

Intracellular Ca2+ regulation in a human prostate stromal cell culture

AIMS

Prostate stromal cell cultures are used in vitro to study the cellular pathophysiology of benign prostatic hyperplasia (BPH), but their functional properties are poorly understood. This study characterized intracellular Ca2+ ([Ca2+]i) regulation in a cultured cell line in comparison to freshly isolated cells, as a background to understanding contractile regulation and cellular proliferation in this tissue.

METHODS

Prostate stromal cells were isolated from either PrS6 cell cultures, with an extended life span by transfection with the SV40 T-antigen, tsA58-U19, or freshly obtained transition zone prostate samples, primary cells. [Ca2+]i was measured in vitro with the indicator Fura-2 by epifluorescence microscopy.

RESULTS

Phenylephrine, high-K+, and caffeine induced Ca2+-transients in primary cells (resting [Ca2+]i 94 +/- 8 nM, n = 29; peak 193 +/- 26 nM, n = 19). In PrS6 cells resting [Ca2+]i was 96 +/- 8 nM (n = 78) and in 34 of these 78 cells, 30 microM phenylephrine increased [Ca2+]i to 296 +/- 28 nM. 5-methyl-urapidil (10-30 microM) inhibited this response in 10 of 16 cells. Spontaneous Ca2+-transients were also observed in 91% of phenylephrine-responsive cells, but in only 20% of non-responsive cells (P < 0.01). Ca2+-transients were also induced by high-K+ solution, and 20 mM caffeine. The latter abolished the response to subsequent phenylephrine application. Depletion of intracellular Ca2+ stores by caffeine or restoration from a Ca2+-free superfusate caused a substantial rise of [Ca2+]i.

CONCLUSIONS

PrS6 prostate stromal cells express functional alpha1-adrenoceptors associated with spontaneous intracellular Ca2+-transients. They exhibit functional Ca2+ channels, intracellular Ca2+ stores, and Ca2+ entry induced by store depletion. Stromal cultures can therefore be used to characterize the cellular physiology of prostate stromal cell contraction and proliferation.

Comparative developmental biology of the mammalian uterus

The uterus is an essential organ for reproduction in mammals. Despite the importance of the uterus for the fertility and health of women and their offspring, relatively little is known about the hormonal, cellular, and molecular mechanisms that regulate development of the uterus in either the fetus or neonate. Disruption of uterine development in the fetus and neonate by genetic defects or exposure to endocrine disruptors can program the function of the uterus in the adult and lead to infertility, cancer, and even death. The intent of this chapter is to review the current knowledge of regulatory factors and pathways governing prenatal organogenesis and postnatal morphogenesis of the uterus in mammals, with a particular focus on laboratory and domestic animals. Prenatal organogenesis, postnatal morphogenesis, and adult functional differentiation of the uterus are complex, multifactorial processes. Although conservation of some factors and pathways are observed between species, it is clear that mutation of candidate genes in the mouse does not always recapitulate the same defects observed in the human. Therefore, comparative biology of the mechanisms regulating uterine development in other species may be useful to identify candidate genes and pathways to understand congenital abnormalities in humans. This knowledge is necessary to develop rational therapies to prevent and treat infertility and to enhance fertility in humans and domestic animals.

Hepatocyte growth factor regulation of uterine epithelial cell transepithelial resistance and tumor necrosis factor alpha release in culture

Underlying stromal cells are essential for the normal development of epithelial cells (ECs) at mucosal surfaces. Recent studies from our laboratory have shown that uterine stromal cells regulate EC integrity, measured as transepithelial resistance (TER) as well as tumor necrosis factor (TNF) alpha alpha secretion by ECs in culture. Using stromal cells in coculture with polarized ECs grown on inserts, we found that stromal cells produce soluble mediators that increase TER and decrease TNFalpha secretion. The purpose of the present study was to identify the mechanisms whereby stromal cells exert their effects on uterine epithelium. We report that hepatocyte growth factor (HGF), a known mesenchymal growth factor that mediates EC proliferation, increases TER but, at the same time, decreases apical TNFalpha release. When ECs and/or stromal cells were incubated with anti-HGF or anti-HGF receptor (HGFR) antibody before HGF, the effects of HGF were blocked. These findings indicate that ECs express the HGFR at their basolateral surfaces and that HGFR mediates the effects of HGF on TER and TNFalpha. Neutralization of stromal cell secretions with antibodies for HGF and HGFR demonstrate that stromal-derived HGF is the mediator of EC TER. In contrast, neither anti-HGF antibody nor HGFR antibody had any effect on stromal cell-induced decreases in TNFalpha secretion. From these results, we conclude that stromal cell regulation of EC TER is mediated through the secretion of stromal HGF. Furthermore, because neutralization of stromal media failed to affect TNFalpha secretion, these findings suggest that other growth factors, in addition to HGF, affect EC cytokine production.

Role of p63 and basal cells in the prostate

The prostate contains two major epithelial cell types - luminal and basal cells - both of which develop from urogenital sinus epithelium. The cell linage relationship between these two epithelial types is not clear. Here we demonstrate that luminal cells can develop independently of basal cells, but that basal cells are essential for maintaining ductal integrity and the proper differentiation of luminal cells. Urogenital sinus (UGS) isolated from p63(+/+) and p63(-/-) embryos developed into prostate when grafted into adult male nude mice. Prostatic tissue that developed in p63(-/-) UGS grafts contained neuroendocrine and luminal cells, but basal cells were absent. Therefore, p63 is essential for differentiation of basal cells, but p63 and thus basal cells are not required for differentiation of prostatic neuroendocrine and luminal epithelial cells. p63(-/-) prostatic grafts also contained atypical mucinous cells, which appeared to differentiate from luminal cells via activation of Src. In the response to castration, regression of p63(-/-) prostate was inordinately severe with almost complete loss of ducts, resulting in the formation of residual cystic structures devoid of epithelium. Therefore, basal cells play critical roles in maintaining ductal integrity and survival of luminal cells. However, regressed p63(-/-) prostate did regenerate in response to androgen administration, indicating that basal cells were not essential for prostatic regeneration.

Disruption of the TIMP-1 gene product is associated with accelerated endometrial gland formation during early postnatal uterine development

Postnatal uterine development is marked by periods of tissue remodeling. The objective of the present study was to examine the role of tissue inhibitor of metalloproteinase-1 (TIMP-1), a regulator of tissue remodeling events, during postnatal uterine development and to assess the phenotypic consequences of disruption of the TIMP-1 gene product during this time period. To accomplish this goal, wild-type and TIMP-1 null mice were sacrificed at Postnatal Days (PNDs) 5, 10, 15, 20, and 25 and uterine morphology, TIMP expression and matrix metalloproteinase (MMP) activity were assessed. In wild-type mice, TIMP-1 mRNA steady-state levels were highest at PND 5, after which expression decreased. TIMP-2 and TIMP-3 expression in wild-type mice showed no significant changes from PND 5 to 25. In TIMP-1 null mice, TIMP-2 and TIMP-3 expression patterns were similar to those in wild-type counterparts with the exception that, at PND 10, TIMP-2 and TIMP-3 expression was significantly lower in the null mice. Endometrial gland number and uterine histology were similar between genotypes at PNDs 5 and 10, but at PNDs 15 and 20, endometrial glands were more abundant in TIMP-1 null mice. Associated with the increased gland density in the null mice was an increase in total MMP activity above the levels expressed in wild-type mice. In summary, disruption of the TIMP-1 gene product is associated with reduced TIMP-2 and TIMP-3 steady-state mRNA levels, elevated MMP activity, and accelerated endometrial gland formation. We conclude that, during early postnatal uterine development, TIMP-1 may be critical for proper endometrial gland development.

Doxazosin and terazosin suppress prostate growth by inducing apoptosis: clinical significance

PURPOSE

Doxazosin and terazosin are known to relax prostate smooth muscle through blockade of alpha 1-adrenergic innervation to the prostate. This action alone however does not fully account for the long-term clinical responses exerted by these drugs in the treatment of patients with benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

Experimental and clinical studies were done to establish the induction of prostate cell apoptosis by alpha 1-adrenoceptor antagonists as a molecular mechanism contributing to their long-term efficacy in the management of lower urinary tract symptoms associated with BPH and to potential suppression of prostate cancer growth.

RESULTS

The data indicate that both doxazosin and terazosin induce apoptosis in prostate cancer cells in vitro and in vivo. The apoptotic effect of doxazosin and terazosin is mediated by a mechanism independent of the alpha1-adrenoceptor blockade, potentially under the direction of the quinazoline nucleus, since the nonquinazoline alpha 1-adrenoceptor antagonist tamsulosin does not elicit an apoptotic response. Recent experimental evidence points to deregulation of signal transduction pathways involving transforming growth factor-beta and disruption of cell attachment to the extracellular matrix (anoikis) as potential mechanisms underlying this apoptotic action of quinazoline based alpha 1-adrenoceptor antagonists against prostate cells.

CONCLUSIONS

The correlation of induced prostate smooth muscle cell apoptosis with improvement of urinary symptoms in patients with BPH treated with doxazosin and terazosin, identifies apoptosis as an additional molecular mechanism for the long term therapeutic impact of these drugs in BPH. Moreover, the apoptotic effect elicited by quinazolines may have high clinical significance in the prevention and treatment of prostate cancer.

Embryonic development of mouse external genitalia: insights into a unique mode of organogenesis

The mammalian external genitalia are specialized appendages for efficient copulation, internal fertilization and display marked morphological variation among species. In this paper, we described the embryonic development of mouse genital tubercle (GT), an anlage of the external genitalia utilizing the scanning electron microscope (SEM) analysis. It has been shown that the Distal Urethral Epithelium (DUE) may fulfill an essential role in the outgrowth control of the GT. Our present SEM analysis revealed a small distal protrusion at the tip of the GT of normal embryos as well as some morphological differences between male and female embryonic external genitalia. Previous analysis shows that the teratogenic dose of Retinoic Acid (RA) induces a drastic marformation of the urethral plate, but not gross abnormalities for GT outgrowth. Interestingly, a small distal protrusion at the tip of GT was clearly observed also after RA treatement. Furthermore, we showed that treatment with anti-androgen flutamide resulted in the demasculinization of the GT in males. The unique character of GT development and the sexual dimorphism are discussed.

Developmental biology of uterine glands

All mammalian uteri contain endometrial glands that synthesize or transport and secrete substances essential for survival and development of the conceptus (embryo/fetus and associated extraembryonic membranes). In rodents, uterine secretory products of the endometrial glands are unequivocally required for establishment of uterine receptivity and conceptus implantation. Analyses of the ovine uterine gland knockout model support a primary role for endometrial glands and, by default, their secretions in peri-implantation conceptus survival and development. Uterine adenogenesis is the process whereby endometrial glands develop. In humans, this process begins in the fetus, continues postnatally, and is completed during puberty. In contrast, endometrial adenogenesis is primarily a postnatal event in sheep, pigs, and rodents. Typically, endometrial adenogenesis involves differentiation and budding of glandular epithelium from luminal epithelium, followed by invagination and extensive tubular coiling and branching morphogenesis throughout the uterine stroma to the myometrium. This process requires site-specific alterations in cell proliferation and extracellular matrix (ECM) remodeling as well as paracrine cell-cell and cell-ECM interactions that support the actions of specific hormones and growth factors. Studies of uterine development in neonatal ungulates implicate prolactin, estradiol-17 beta, and their receptors in mechanisms regulating endometrial adenogenesis. These same hormones appear to regulate endometrial gland morphogenesis in menstruating primates and humans during reconstruction of the functionalis from the basalis endometrium after menses. In sheep and pigs, extensive endometrial gland hyperplasia and hypertrophy occur during gestation, presumably to provide increasing histotrophic support for conceptus growth and development. In the rabbit, sheep, and pig, a servomechanism is proposed to regulate endometrial gland development and differentiated function during pregnancy that involves sequential actions of ovarian steroid hormones, pregnancy recognition signals, and lactogenic hormones from the pituitary or placenta. That disruption of uterine development during critical organizational periods can alter the functional capacity and embryotrophic potential of the adult uterus reinforces the importance of understanding the developmental biology of uterine glands. Unexplained high rates of peri-implantation embryonic loss in humans and livestock may reflect defects in endometrial gland morphogenesis due to genetic errors, epigenetic influences of endocrine disruptors, and pathological lesions.

Neonatal ovine uterine development involves alterations in expression of receptors for estrogen, progesterone, and prolactin

Effects of age on uterine histoarchitecture, cell proliferation, and hormone receptor expression were determined for neonatal ewe lambs from birth (Postnatal Day [PND] 0) to PND 56. Uteri were histologically evaluated and proliferating cell nuclear antigen (PCNA), estrogen receptor alpha (ER-alpha), progesterone receptor (PR), and prolactin receptor (PRL-R) expression were characterized by in situ hybridization (ISH), immunohistochemistry, or both. The most striking feature of neonatal uterine development was the genesis and development of glands in the intercaruncular areas of endometrium. After birth, endometrial glandular epithelium (GE) budded and differentiated into the underlying stroma from the luminal epithelium (LE) between PNDs 1 and 7. Between PNDs 14 and 56, extensive coiling and branching morphogenesis of nascent endometrial glands occurred. By PND 56, the uterine wall appeared to be histoarchitecturally mature. At birth, nuclear PCNA protein was strongly detected in LE. Between PNDs 7 and 56, high levels of PCNA, ER-alpha, and PR gene expression were detected in both nascent and developing GE. Higher levels of PCNA and ER-alpha expression were detected in GE at the tips of developing glands as well as in the surrounding stroma. Progesterone was below detectable limits in serum. Serum estradiol-17beta levels were high on PND 1, increased from PNDs 14 to 28, and declined from PND 42 to PND 56. Serum PRL levels increased from PNDs 1 to 14 and declined thereafter. Using ISH and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis, expression of mRNAs for short and long forms of the ovine PRL-R were first detected in nascent GE on PND 7 and increased between PNDs 7 and 56 in proliferating and differentiating GE. These results indicate that 1) uterine gland genesis is initiated between PNDs 1 and 7 after birth and is essentially completed by PND 56; 2) neonatal uterine morphogenesis involves temporal and spatial alterations in cell proliferation and ER-alpha, PR, and PRL-R gene expression; 3) PRL-R expression is a unique marker of GE differentiation and proliferation; and 4) serum estradiol-17beta and PRL levels increase during the onset of GE tubular branching morphogenesis. Results support the hypothesis that neonatal ovine uterine development involves epithelial PRL-R and ER-alpha activation to stimulate and maintain endometrial gland genesis and branching morphogenesis.

Prevention of vaginal shortening following radical hysterectomy

We describe a surgical procedure and post-operative management for the prevention of vaginal shortening following radical hysterectomy. A total of 452 patients who underwent hysterectomies were examined prospectively depending on the operation method. This study showed that our procedure was effective in the prevention of vaginal shortening following radical hysterectomy. Preservation of the ovaries appeared to be important in preventing vaginal shortening, and post-operative hormone replacement therapy was not as effective as the preservation of the ovaries. The effect of external irradiation on vaginal shortening was not conspicuous in the case that the ovaries were preserved.

Ovine uterine gland knock-out model: effects of gland ablation on the estrous cycle

Ovine endometrial gland development is a postnatal event that can be inhibited epigenetically by chronic exposure of ewe lambs to a synthetic progestin from birth to puberty. As adults, these neonatally progestin-treated ewes lack endometrial glands and display a uterine gland knockout (UGKO) phenotype that is useful as a model for study of endometrial function. Here, objectives were to determine: 1) length of progestin exposure necessary from birth to produce the UGKO phenotype in ewes; 2) if UGKO ewes display normal estrous cycles; and 3) if UGKO ewes could establish and/or maintain pregnancy. Ewe lambs (n = 22) received a Norgestomet (Nor) implant at birth and every two weeks thereafter for 8 (Group I), 16 (Group II), or 32 (Groups III and IV) weeks. Control ewe lambs (n = 13) received no Nor treatment (Groups V and VI). Ewes in Groups I, II, III, and VI were hemihysterectomized (Hhx) at 16 weeks of age. After puberty, the remaining uterine horn in Hhx ewes was removed on either Day 9 or 15 of the estrous cycle (Day 0 = estrus). Histological analyses of uteri indicated that progestin exposure for 8, 16, or 32 weeks prevented endometrial adenogenesis and produced the UGKO phenotype in adult ewes. Three endometrial phenotypes were consistently observed in Nor-treated ewes: 1) no glands, 2) slight glandular invaginations into the stroma, and 3) limited numbers of cyst- or gland-like structures in the stroma. Overall patterns of uterine progesterone, estrogen, and oxytocin receptor expression were not different in uteri from adult cyclic control and UGKO ewes. However, receptor expression was variegated in the ruffled luminal epithelium of uteri from UGKO ewes. Intact UGKO ewes displayed altered estrous cycles with interestrous intervals of 17 to 43 days, and they responded to exogenous prostaglandin F(2 approximately ) (PGF) with luteolysis and behavioral estrus. During the estrous cycle, plasma concentrations of progesterone in intact control and UGKO ewes were not different during metestrus and diestrus, but levels did not decline in many UGKO ewes during late diestrus. Peak peripheral plasma concentrations of PGF metabolite, in response to an oxytocin challenge on Day 15, were threefold lower in UGKO compared to control ewes. Intact UGKO ewes bred repeatedly to intact rams did not display evidence of pregnancy based on results of ultrasound. Collectively, results indicate that 1) transient, progestin-induced disruption of ovine uterine development from birth alters both structural and functional integrity of the adult endometrium; 2) normal adult endometrial integrity, including uterine glands, is required to insure a luteolytic pattern of PGF production; and 3) the UGKO phenotype, characterized by the absence of endometrial glands and a compact, disorganized endometrial stroma, limits or inhibits the capacity of uterine tissues to support the establishment and/or maintenance of pregnancy.

Expression of androgen receptor mRNA during mouse embryogenesis

Androgen receptor (AR) is a member of the nuclear receptor superfamily which acts as a ligand-dependent transcription factor (Beato, M., Herrlich, P., Schütz, 1989. Steroid hormone receptors: many actors in search of a plot. Cell 83, 851-857). It plays a pivotal role in sexual development and reproduction (Wilson, J.D., Griffin, J.E., George, F.W., Leshin, M., 1981. The role of gonadal steroids in sexual differentiation. Rec. Prog. Horm. Res. 37, 1-39; Jost, A., 1990. Hormonal control of the masculinization of the body. In: Baulieu, E.E., Kelly, D.A., (Eds.), Hormones, from Molecules to Disease. Chapman and Hall, New York and London, pp. 439-442.). Mutations in the AR sequence cause a number of physiological disorders, such as partial and complete androgen insensitivity syndromes, that lead to abnormal sexual development (Patterson, M.N., McPhaul, M.J., Hughes, I.A., 1994. Androgen insensitivity syndrome. Ballière's Clin. Endocrinol. Metab. 8, 379-404.). There are indications that AR may also have other functions. For example, structural alterations of the AR sequence have been implicated in prostate cancer (Visakorpi, T., Huytinen, E., Koivisto, P., Tanner, M., Keinänen, R., Palmberg, C., Palotie, A., Tammela, T., Isola, J., Kallioniemi, O.-P., 1995. In vivo amplification of the androgen receptor gene and progression of human prostate cancer. Nature Genet. 9, 401-406.) and in the development of spinal and bulbar muscular atrophy, a neurodegenerative disease (Kennedy, W.R., Alter, M., Sung, J.H., 1968. Progressive proximal spinal and bulbar muscular atrophy of late onset: a sex-linked recessive trait. Neurology 18, 671-680.). Here, we have investigated the spatial and temporal expression of AR during mouse organogenesis by in situ hybridisation. We demonstrate that AR transcripts occur in the developing external genitalia, pituitary, adrenals, kidneys and musculus levator ani, in addition to the known expression sites in the Wolffian ducts and its derivatives and during development of the mammary glands.

Regeneration of bladder urothelium, smooth muscle, blood vessels and nerves into an acellular tissue matrix

PURPOSE

To study the cellular events occurring during bladder development and regeneration we developed an in vivo model of bladder augmentation with an acellular tissue graft. We propose that the extracellular matrix orchestrates the regenerative capacity of host bladder cells (urothelium, smooth muscle, blood vessels and nerve cells) after bladder augmentation with acellular tissue matrix.

MATERIALS AND METHODS

A total of 40 adult rats underwent partial cystectomy and augmentation with a patch of extracellular matrix representing the full thickness of rat gastric or bladder tissue. Sections were examined histologically to assess urothelial, smooth muscle and neuronal invasion of the graft.

RESULTS

A total of 32 rats was evaluated 1 day to 26 weeks after grafting. Epithelialization occurred by day 4, accompanied by granulocytic infiltration. Smooth muscle regenerated 2 weeks after grafting in juxtaposition to epithelial surfaces and it matured into normal sized bundles by 26 weeks. Neovascularity was noted 2 weeks postoperatively. Neural elements formed around developing smooth muscle bundles as early as 4 weeks after grafting.

CONCLUSIONS

We demonstrated the regeneration of urothelium, smooth muscle, blood vessels and nerves within a full thickness grafted acellular tissue matrix scaffold in the rat. The spatial orientation of these elements suggests that mesenchymal-epithelial interactions occur during phenotypic regeneration of the bladder. Urothelium appears to regulate the early forming smooth muscle. This in vivo model provides a suitable method to study cellular events during regeneration.

Distribution of immunoreactive androgen-binding protein/sex hormone-binding globulin in tissues of the fetal rat

Androgen-binding protein/sex hormone-binding globulin (ABP/SHBG) is an extracellular carrier protein that binds androgens and estrogens with high affinity. In the adult, ABP/SHBG is thought to function in the male reproductive system and the general circulation in both sexes to modulate the actions of sex steroids. The ABP/SHBG gene is also expressed in the embryonic rat liver, where SHBG is secreted into the fetal blood of male and female rats. The embryo also expresses an alternative SHBG with a unique N-terminal sequence. In this study, the distribution of immunoreactive SHBG in the 17-day-old male fetal rat was determined with six antisera. In general, all of the antisera reacted with the same structures. Specific tissue immunoreactivity was mostly cytoplasmic and/or extracellular. By far the most prominent immunoreactive structures were the mesoderm-derived tissues: connective tissue, striated and cardiac muscle, cartilage, and the liver hematopoietic system. In addition, all regions of the fetal brain contained immunoreactive neurons. In the developing male reproductive system, there was minor reactivity in the testicular cords, whereas the connective tissue in the differentiating Wolffian duct stained with all of the antisera. The Wolffian duct epithelium and epithelia in other developing organs contained small amounts of immunoreactive SHBG, except for the lung, which stained in the epithelial extracellular matrix. An antibody raised against a unique N-terminal peptide specific for the alternative SHBG protein revealed that it was also present in many tissues. These data suggest that SHBG is important for the differentiation of mesodermal tissues. SHBG may modulate the action of androgens in embryonic stroma, thereby regulating development of the epithelium in hormone-dependent tissues.