Distinct functions and regulation of epithelial progesterone receptor in the mouse cervix, vagina, and uterus

High incidence of imperforate vagina in ADGRA3-deficient mice

BACKGROUND

Ten percent of the female population suffers from congenital abnormalities of the vagina, uterus, or oviducts, with severe consequences for reproductive and psychological health. Yet, the underlying causes of most of these malformations remain largely unknown. ADGRA3 (GPR125) is involved in WNT signaling and planar cell polarity, mechanisms vital to female reproductive tract development. Although ADGRA3 is a well-established spermatogonial stem cell marker, its role within the female urogenital system remains unclear.

RESULTS

In this study, we found Adgra3 to be expressed throughout the murine female urogenital system, with higher expression pre-puberty than after sexual maturation. We generated a global Adgra3-/- mouse line and observed imperforate vagina in 44% of Adgra3-/- females, resulting in distension of the reproductive tract and infertility. Ovarian morphology, plasma estradiol, ovarian Cyp19a1, and vaginal estrogen receptor α (Esr1) expression were unaffected. However, compared to controls, a significantly lower bone mineral density was found in Adgra3-/- mice. Whereas vaginal opening in mice is an estrogen-dependent process, 17β-estradiol treatment failed to induce vaginal canalization in Adgra3-/- mice. Furthermore, a marked reduction in vaginal and ovarian progesterone receptor expression was observed concomitant with an upregulation of apoptotic regulators Bcl2, Bid, and Bmf in adult Adgra3-/- females with a closed vagina.

CONCLUSIONS

Our collective results shed new insights into the complex mechanisms by which the adhesion receptor ADGRA3 regulates distal vaginal tissue remodeling during vaginal canalization via altered sex hormone responsiveness and balance in apoptotic regulators. This highlights the potential of ADGRA3 as a target in diagnostic screening and/or therapy for obstructive vaginal malformations in humans.

Ovarian sex steroid and epithelial control of immune responses in the uterus and oviduct: human and animal models†

The female reproductive tract (FRT), including the uterus and oviduct (Fallopian tube), is responsible for maintaining an optimal microenvironment for reproductive processes, such as gamete activation and transportation, sperm capacitation, fertilization, and early embryonic and fetal development. The mucosal surface of the FRT may be exposed to pathogens and sexually transmitted microorganisms due to the opening of the cervix during mating. Pathogens and endotoxins may also reach the oviduct through the peritoneal fluid. To maintain an optimum reproductive environment while recognizing and killing pathogenic bacterial and viral agents, the oviduct and uterus should be equipped with an efficient and rigorously controlled immune system. Ovarian sex steroids can affect epithelial cells and underlying stromal cells, which have been shown to mediate innate and adaptive immune responses. This, in turn, protects against potential infections while maintaining an optimal milieu for reproductive events, highlighting the homeostatic involvement of ovarian sex steroids and reproductive epithelial cells. This article will discuss how ovarian sex steroids affect the immune reactions elicited by the epithelial cells of the non-pregnant uterus and oviduct in the bovine, murine, and human species. Finally, we propose that there are regional and species-specific differences in the immune responses in FRT.

Transcriptional profiling of mucus production and modification in rhesus macaque endocervical cells under hormonal regulation

Objective

Endocervical mucus production is a key regulator of fertility throughout the menstrual cycle. With cycle-dependent variability in mucus quality and quantity, cervical mucus can either facilitate or block sperm ascension into the upper female reproductive tract. This study seeks to identify genes involved in the hormonal regulation of mucus production, modification, and regulation through profiling the transcriptome of endocervical cells from the non-human primate, the Rhesus Macaque (Macaca mulatta).

Design

Experimental.

Setting

Translational science laboratory.

Intervention

We treated differentiated primary endocervical cultures with estradiol (E2) and progesterone (P4) to mimic peri-ovulatory and luteal-phase hormonal changes. Using RNA-sequencing, we identified differential expression of gene pathways and mucus producing and modifying genes in cells treated with E2 compared to hormone-free conditions and E2 compared to E2-primed cells treated with P4.

Main Outcome Measures

We pursued differential gene expression analysis on RNA-sequenced cells. Sequence validation was done using qPCR.

Results

Our study identified 158 genes that show significant differential expression in E2-only conditions compared to hormone-free control, and 250 genes that show significant differential expression in P4-treated conditions compared to E2-only conditions. From this list, we found hormone-induced changes in transcriptional profiles for genes across several classes of mucus production, including ion channels and enzymes involved in post-translational mucin modification that have not previously been described as hormonally regulated.

Conclusion

Our study is the first to use an in vitro culture system to create an epithelial-cell specific transcriptome of the endocervix. As a result, our study identifies new genes and pathways that are altered by sex-steroids in cervical mucus production.

Hormonal regulation of non-cystic fibrosis transmembrane conductance regulator ion channels in the endocervix

OBJECTIVE

To characterize ion channel expression and localization in the endocervix under different hormonal conditions using a nonhuman primate primary endocervical epithelial cell model.

DESIGN

Experimental.

SETTING

University-based, translational science laboratory.

INTERVENTIONS

We cultured and treated conditionally reprogrammed primary rhesus macaque endocervix cells with estradiol and progesterone and measured gene expression changes for several known ion channel and ion channel regulators of mucus secreting epithelia. Using both rhesus macaque endocervical samples and human samples, we localized channels in the endocervix using immunohistochemistry.

MAIN OUTCOME MEASURES

The relative abundance of transcripts was evaluated using real-time polymerase chain reaction. Immunostaining results were evaluated qualitatively.

RESULTS

Compared with controls, we found that estradiol increased gene expression for ANO6, NKCC1, CLCA1, and PDE4D. Progesterone down-regulated gene expression for ANO6, SCNN1A, SCNN1B, NKCC1, and PDE4D (P≤.05). Immunohistochemistry confirmed endocervical cell membrane localization of ANO1, ANO6, KCNN4, LRR8CA, and NKCC1.

CONCLUSIONS

We found several ion channels and ion channel regulators that are hormonally sensitive in the endocervix. These channels, therefore, may play a role in the cyclic fertility changes in the endocervix and could be further investigated as targets for future fertility and contraceptive studies.

Dynamic states of cervical epithelia during pregnancy and epithelial barrier disruption

The cervical epithelium undergoes changes in proliferation, differentiation, and function that are critical to ensure fertility and maintain pregnancy. Here, we identify cervical epithelial subtypes in non-pregnant, pregnant, and in labor mice using single-cell transcriptome and spatial analysis. We identify heterogeneous subpopulations of epithelia displaying spatial and temporal specificity. Notably in pregnancy, two goblet cell subtypes are present in the most luminal layers with one goblet population expanding earlier in pregnancy than the other goblet population. The goblet populations express novel protective factors and distinct mucosal networks. Single-cell analysis in a model of cervical epithelial barrier disruption indicates untimely basal cell proliferation precedes the expansion of goblet cells with diminished mucosal integrity. These data demonstrate how the cervical epithelium undergoes continuous remodeling to maintain dynamic states of homeostasis in pregnancy and labor, and provide a framework to understand perturbations in epithelial health that increase the risk of premature birth.

The injections of mitochondrial fusion promoter M1 during proestrus disrupt the progesterone secretion and the estrous cycle in the mouse

After ovulation, the mitochondrial enzyme CYP11A1 cleavage the cholesterol into pregnenolone for progesterone synthesis, suggesting that mitochondrial dynamics play a vital role in the female reproductive system. The changes in the mitochondria dynamics throughout the ovarian cycle have been reported in literature, but the correlation to its role in the ovarian cycle remains unclear. In this study, mitochondrial fusion promotor, M1, was used to study the impact of mitochondria dynamics in the female reproductive system. Our results showed that M1 treatment in mice can lead to the disruptions of estrous cycles in vagina smears. The decrease in serum LH was recorded in the animal. And the inhibitions of progesterone secretion and ovulations were observed in ovarian culture. Although no significant changes in mitochondrial networks were observed in the ovaries, significant up-regulation of mitochondrial respiratory complexes was revealed in M1 treatments through transcriptomic analysis. In contrast to the estrogen and steroid biosynthesis up-regulated in M1, the molecules of extracellular matrix, remodeling enzymes, and adhesion signalings were decreased. Collectively, our study provides novel targets to regulate the ovarian cycles through the mitochondria. However, more studies are still necessary to provide the functional connections between mitochondria and the female reproductive systems.

Progesterone and its receptor signaling in cervical remodeling: Mechanisms of physiological actions and therapeutic implications

The remodeling of the cervix from a closed rigid structure to one that can open sufficiently for passage of a term infant is achieved by a complex series of molecular events that in large part are regulated by the steroid hormones progesterone and estrogen. Among hormonal influences, progesterone exerts a dominant role for most of pregnancy to initiate a loss of tissue strength yet maintain competence in a phase termed softening. Equally important are the molecular events that abrogate progesterone function in late pregnancy to allow a loss of tissue competence and strength during cervical ripening and dilation. In this review, we focus on current understanding by which progesterone receptor signaling for the majority of pregnancy followed by a loss/shift in progesterone receptor action at the end of pregnancy, collectively ensure cervical remodeling as necessary for successful parturition.

Efficient cell chatting between embryo and uterus ensures embryo implantation

Embryo implantation is one of the hottest topics during female reproduction since it is the first dialogue between maternal uterus and developing embryo whose disruption will contribute to adverse pregnancy outcome. Numerous achievements have been made to decipher the underlying mechanism of embryo implantation by genetic and molecular approaches accompanied with emerging technological advances. In recent decades, raising concepts incite insightful understanding on the mechanism of reciprocal communication between implantation competent embryos and receptive uterus. Enlightened by these gratifying evolvements, we aim to summarize and revisit current progress on the critical determinants of mutual communication between maternal uterus and embryonic signaling on the perspective of embryo implantation to alleviate infertility, enhance fetal health, and improve contraceptive design.

Host and Microbiome Interplay Shapes the Vaginal Microenvironment

The female reproductive tract harbors a unique microbiome, especially the vagina. The human vaginal microbiome exhibits a low diversity and is dominated by Lactobacillus species, compared to the microbiome of other organs. The host and vaginal microbiome mutually coexist in the vaginal microenvironment. Host cells provide Lactobacillus glycogen as an energy source, and Lactobacillus produce lactic acid, which lowers vaginal pH thereby preventing growth of other bacteria. Bacterial vaginosis can modulate host immune systems, and is frequently associated with various aspects of disease, including sexually transmitted infection, gynecologic cancer, and poor pregnancy outcomes. Because of this, numerous studies focused on the impact of the vaginal microbiome on women`s health and disease. Furthermore, numerous epidemiologic studies also have demonstrated various host factors regulate the vaginal microbiome. The female reproductive tract undergoes constant fluctuations due to hormonal cycle, pregnancy, and other extrinsic factors. Depending on these fluctuations, the vaginal microbiome composition can shift temporally and dynamically. In this review, we highlight the current knowledge of how host factors modulate vaginal microbiome composition and how the vaginal microbiome contributes to maintaining homeostasis or inducing pathogenesis. A better understanding of relationship between host and vaginal microbiome could identify novel targets for diagnosis, prognosis, or treatment of microbiome-related diseases.

Conditional knockout of leptin receptor in the female reproductive tract reduces fertility due to parturition defects in mice

Leptin is required for fertility, including initiation of estrous cycles. It is therefore challenging to assess the role of leptin signaling during pregnancy. While neuron-specific transgene approaches suggest that leptin signaling in the central nervous system is most important, experiments with pharmacologic inhibition of leptin in the uterus or global replacement of leptin during pregnancy suggest leptin signaling in the reproductive tract may be required. Here, conditional leptin receptor knockout (Lepr cKO) with a progesterone receptor-driven Cre recombinase was used to examine the importance of leptin signaling in pregnancy. Lepr cKO mice have almost no leptin receptor in uterus or cervix, and slightly reduced leptin receptor levels in corpus luteum. Estrous cycles and progesterone concentrations were not affected by Lepr cKO. Numbers of viable embryos did not differ between primiparous control and Lepr cKO dams on days 6.5 and 17.5 of pregnancy, despite a slight reduction in the ratio of embryos to corpora lutea, showing that uterine leptin receptor signaling is not required for embryo implantation. Placentas of Lepr cKO dams had normal weight and structure. However, over four parities, Lepr cKO mice produced 22% fewer live pups than controls, and took more time from pairing to delivery by their fourth parity. Abnormal birth outcomes of either dystocia or dead pups occurred in 33% of Lepr cKO deliveries but zero control deliveries, and the average time to deliver each pup after crouching was significantly increased. Thus, leptin receptor signaling in the reproductive tract is required for normal labor and delivery. Summary sentence. Mice lacking leptin receptor in the reproductive tract produce fewer live pups and have more adverse labor outcomes than controls, but normal numbers of embryos near term, showing that leptin receptor signaling is required for normal parturition.

Estrogen Inhibits Epithelial Progesterone Receptor-Dependent Progestin Therapy Efficacy in a Mouse Model of Cervical Cancer

Although the uterine cervix responds to the female sex hormone change, the role of progesterone in cervical cancer is poorly understood. It has been shown that medroxyprogesterone acetate (MPA) regresses cervical cancer in the transgenic mouse model expressing human papillomavirus type 16 E6 and E7 oncogenes. As MPA interacts most strongly with progesterone receptor (PR), we reasoned that PR would contribute to MPA-induced regression of cervical cancer. We also hypothesized that estrogen influences the therapeutic activity of MPA because it promotes cervical cancer growth in the same mouse model. The present study showed that the deletion of Pgr in the cervical cancer cells ablated the MPA's therapeutic effect in the human papillomavirus transgenic mouse model. Additionally, estrogen attenuated cancer regression by MPA in the same model system. These observations indicate that MPA can effectively regress cervical cancer only when cancer cells express PR and estrogen levels are low. These results suggest that, if translatable, MPA should be administered when estrogen levels are low in patients with PR-positive cervical cancer.

Female Reproductive Systems: Hormone Dependence and Receptor Expression

The female reproductive system which consists of the ovaries, uterus (myometrium, endometrium), Fallopian tubes, cervix and vagina is exquisitely sensitive to the actions of steroid hormones. The ovaries play a key role in the synthesis of bioactive steroids (oestrogens, androgens, progestins) that act both within the tissue (intracrine/paracrine) as well as on other reproductive organs following release into the blood stream (endocrine action). Sex steroid receptors encoded by the oestrogen (ESR1, ESR2), progesterone (PR) and androgen (AR) receptor genes, which are members of the superfamily of ligand activated transcription factors are widely expressed within these tissues. These receptors play critical role(s) in regulation of cell proliferation, ovulation, endometrial receptivity, myometrial cell function and inflammatory cell infiltration. Our understanding of their importance has been informed by studies on human tissues and cells, which have employed immunohistochemistry as well as a wide range of molecular and genetic methods to identify which processes are dependent steroid ligand activation. The development of mice with targeted deletions of each of these receptors has provided complementary data that has extended our appreciation of cell-cell interactions in the fine tuning of reproductive tissue function. This large body of work has formed the basis of new and improved therapeutics to treat conditions such as infertility.

Functional roles of female sex hormones and their nuclear receptors in cervical cancer

There has been little progress for several decades in modalities to treat cervical cancer. While the cervix is a hormone-sensitive tissue, physiologic roles of estrogen receptor α (ERα), progesterone receptor (PR), and their ligands in this tissue are poorly understood. It has hampered critical assessments of data in early epidemiologic and clinical studies for cervical cancer. Experimental evidence obtained from studies using mouse models has provided new insights into the molecular mechanism of ERα and PR in cervical cancer. In a mouse model expressing human papillomavirus (HPV) oncogenes, exogenous estrogen promotes cervical cancer through stromal ERα. In the same mouse model, genetic ablation of PR promotes cervical carcinogenesis without exogenous estrogen. Medroxyprogesterone acetate, a PR-activating drug, regresses cervical cancer in the mouse model. These results support that ERα and PR play opposite roles in cervical cancer. They further support that ERα inhibition and PR activation may be translated into valuable treatment for a subset of cervical cancers.

Organoids of the Female Reproductive Tract: Innovative Tools to Study Desired to Unwelcome Processes

The pelviperineal organs of the female reproductive tract form an essential cornerstone of human procreation. The system comprises the ectodermal external genitalia, the Müllerian upper-vaginal, cervical, endometrial and oviductal derivatives, and the endodermal ovaries. Each of these organs presents with a unique course of biological development as well as of malignant degeneration. For many decades, various preclinical in vitro models have been employed to study female reproductive organ (patho-)biology, however, facing important shortcomings of limited expandability, loss of representativeness and inadequate translatability to the clinic. The recent emergence of 3D organoid models has propelled the field forward by generating powerful research tools that in vitro replicate healthy as well as diseased human tissues and are amenable to state-of-the-art experimental interventions. Here, we in detail review organoid modeling of the different female reproductive organs from healthy and tumorigenic backgrounds, and project perspectives for both scientists and clinicians.

Transcriptomic profile of VEGF-regulated genes in human cervical epithelia

Cervical epithelial cells play a central role in cervical remodeling (CR) during pregnancy and cervical events during menstrual cycle, including mounting physical and immunological barriers, proliferation and differentiation, maintenance of fluid balance, and likely in withstanding the mechanical force exerted by the growing fetus prior to term. In the present study, we attempt to decipher the specific roles of VEGF in fetal human cervical epithelial cells by delineating VEGF signature genes using RNA sequencing in order to characterize the specific biological effects of VEGF in these cells.Out of a total of 25,000 genes screened, 162 genes were found to be differentially expressed in human cervical epithelial cells, of which 12 genes were found to be statistically significantly differentially expressed. The differentially expressed genes (162) were categorized by biological function, which included (1) proliferation, (2) immune response, (3) structure/matrix, (4) mitochondrial function, and (5) cell adhesion/communication and others (pseudogenes, non-coding RNA, miscellaneous genes, and uncharacterized genes). We conclude that VEGF plays a key role in CR by altering the expression of genes that regulate proliferation, immune response, energy metabolism and cell structure, and biological processes that are essential to development and likely CR.

Progesterone Receptor Is a Haploinsufficient Tumor-Suppressor Gene in Cervical Cancer

Tumor-suppressor genes (TSG) are often deleted or transcriptionally suppressed in cancer. PGR codes for progesterone receptor (PR), a transcription factor whose function depends on its ligand. Although PR expression is often undetectable in cervical cancer, its relevance to the endocrine-related etiology of this prevalent gynecological disease remains unclear. In this study, we show that the deletion of one Pgr allele in cervical epithelium promoted spontaneous cervical cancer in human papilloma viral oncogene-expressing transgenic mice as efficiently as the ablation of both Pgr alleles. We also show that tumors arising in the transgenic mice with one or both Pgr alleles did not express PR or expressed at the reduced levels compared with the normal epithelium. PR status correlated with estrogen receptor α (ERα) status in the mouse model and the Cancer Genome Atlas (TCGA) dataset. TCGA data analyses revealed that PGR expression significantly decreased in cervical cancer and that the biallelic deletion of PGR was rare. Furthermore, low PGR expression was associated with poor prognosis in young patients with cervical cancer. These discoveries point to PGR as a haploinsufficient TSG in the uterine cervix. They also raise the possibility that the restoration of PGR expression may improve the survival rate. IMPLICATIONS: The decreased expression of PR may increase the risk of cervical cancer in human papillomavirus-infected women. VISUAL OVERVIEW: http://mcr.aacrjournals.org/content/molcanres/19/1/42/F1.large.jpg.

TRPM7 is involved in acid-induced necrotic cell death in a manner sensitive to progesterone in human cervical cancer cells

Because intravaginal pH is strongly acidic, it is important to investigate the effects of acidosis on cervical cancer cells. Recently, in response to strong acidosis, human cervical cancer HeLa cells were shown to exhibit necrosis after showing persistent cell swelling induced by Cl⁻ influx. Since cation influx should be accompanied with Cl⁻ influx to drive water inflow causing cell swelling, we here studied on the nature of acidotoxic cation conductance. The mRNA/protein expression was assessed by RT‐PCR and Western blotting. Ionic currents were measured by patch‐clamping techniques. Cell counting/viability and colorimetric assays were applied to assess proliferation rate and caspase 3/7 activity, respectively. Cell volume and size were measured by electronic sizing and video‐microscopic measurements, respectively. Acid exposure enhanced TRPM7 activity endogenously expressed in HeLa cells and exogenously overexpressed in HEK293T cells. Gene silencing of TRPM7 abolished acid‐induced cell swelling and necrosis but rather induced activation of apoptotic caspase 3/7 in HeLa cells. Overexpression with the pore charge‐neutralizing D1054A mutant suppressed acid‐enhanced cation currents, acid‐induced cell swelling, and acidotoxic necrosis in HEK293T cells. Progesterone treatment was surprisingly found to suppress molecular and functional expression of TRPM7 and cell proliferation in HeLa cells. Furthermore, in the progesterone‐treated cells, acid exposure did not induce persistent cell swelling followed by necrosis but induced persistent cell shrinkage and apoptotic cell death. These results indicate that in the human cervical cancer cells, TRPM7 is essentially involved in acidotoxic necrotic cell death, and progesterone inhibits TRPM7 expression thereby inhibiting acidotoxic necrosis by switching to apoptosis.

Conditionally reprogrammed macaque endocervical cells retain steroid receptor expression and produce mucus

Cervical mucus produced by the endocervix plays an essential role as a hormonally induced regulator of female fertility. Cervical mucus fluctuates in both physical characteristics and in sperm penetrability in response to estrogens and progestogens. However, the mechanisms by which steroid hormones change mucus remains poorly understood. Current in vitro models have limited capability to study these questions as primary endocervical cells possess limited expansion potential, and immortalized cells lose in vivo characteristics such as steroid sensitivity. Here we overcome these limitations by establishing an in vitro primary endocervical cell culture model using conditionally reprogrammed cells (CRCs). CRC culture utilizes a Rho-kinase inhibitor and a fibroblast feeder layer to expand proliferative potential of epithelial cell types that have normally short in vitro life spans. In our studies, we produce CRC cultures using primary endocervical cells from adult female rhesus macaques (Macaca mulatta). We demonstrate that primary endocervical cells from the nonhuman primate can be robustly expanded using a CRC method, while retaining steroid receptor expression. Moreover, when removed from CRC conditions and switched to differentiation conditions, these cells are able to differentiate and produce mucus including MUC5B, the most prevalent mucin of the endocervix. We conclude that this method provides a promising in vitro platform for conducting mechanistic studies of cervical mucus regulation as well as for screening new therapeutic targets for fertility regulation and diseases of the endocervix.

Medroxyprogesterone Acetate Prevention of Cervical Cancer through Progesterone Receptor in a Human Papillomavirus Transgenic Mouse Model

Cervical dysplastic lesions called cervical intraepithelial neoplasias (CINs) need be treated to prevent cervical cancer. Currently available surgical procedures are effective, but the development of noninvasive treatment is warranted. In human papillomavirus transgenic mice engineered to express human papillomavirus type 16 E6 and E7, short-term treatment with 17β-estradiol induces CINs that progress to cervical cancer if the treatment is continued. In the present study, this mouse model was used to determine whether medroxyprogesterone acetate (MPA), a progestin drug, is chemopreventive. Human papillomavirus transgenic mice bearing CIN lesions were treated with MPA plus 17β-estradiol. Unlike control mice treated with 17β-estradiol alone, cervical cancer was absent in the MPA-treated mice. This observation suggests that MPA prevented CIN from progressing to invasive cancer. MPA was associated with inhibited cell proliferation and the promotion of apoptosis in CIN lesions. Confirming the role of the progesterone receptor, the preventive effect of MPA was absent in human papillomavirus transgenic mice in which the expression of progesterone receptor was genetically ablated. These results suggest that MPA is efficient in treating progesterone receptor–positive CIN lesions. These findings provide the basis for a biomarker-driven clinical trial of the secondary prevention of cervical cancer.

Use of contraceptive depot medroxyprogesterone acetate is associated with impaired cervicovaginal mucosal integrity

BACKGROUND

Injectable depot medroxyprogesterone acetate (DMPA) is one of the most popular contraception methods in areas of high HIV seroprevalence. Evidence is accumulating that use of DMPA might be associated with an increased risk of HIV-1 acquisition by women; however, mechanisms of this association are not completely understood. The goal of this study was to gain insight into mechanisms underlying the possible link between use of DMPA and risk of HIV-1 acquisition, exploring transcription profiling of ectocervical tissues.

METHODS

Healthy women received either DMPA (n = 31) or combined oral contraceptive (COC), which has not been linked to an increased risk of HIV acquisition (n = 32). We conducted a comparative microarray-based whole-genome transcriptome profiling of human ectocervical tissues before and after 6 weeks of hormonal contraception use.

RESULTS

The analysis identified that expression of 235 and 76 genes was significantly altered after DMPA and COC use, respectively. The most striking effect of DMPA, but not COC, was significantly altered expression (mostly downregulation) of many genes strategically involved in the maintenance of mucosal barrier function; the alterations, as indicated by Ingenuity Pathway Analysis (IPA), were most likely due to the DMPA-induced estrogen deficiency. Furthermore, IPA predicted that transcriptome alterations related to ectocervical immune responses were in general compatible with an immunosuppressive effect of DMPA, but, in some women, also with an inflammatory-like response.

CONCLUSION

Our results suggest that impairment of cervicovaginal mucosal integrity in response to DMPA administration is an important mechanism contributing to the potential increased risk of HIV-1 acquisition in DMPA users.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01421368.

FUNDING

This study was supported by the United States Agency for International Development (USAID) under Cooperative Agreement GPO-A-00-08-00005-00.

Tissue interactions and estrogenic response during human female fetal reproductive tract development

The role of tissue interactions was explored to determine whether epithelial differentiation within the developing human reproductive tract is induced and specified by mesenchyme in tissue recombinants composed of mouse vaginal mesenchyme + human uterine tubal epithelium (mVgM+hTubE). The tissue recombinants were grown in DES-treated ovariectomized athymic mice. After 2-4 weeks of in vivo growth, several vaginal specific features were expressed in the human tubal epithelium. The mesenchyme-induced effects included morphological change as well as expression of several immunohistochemical markers. Although the mesenchyme-induced shift in vaginal differentiation in the human tubal epithelium was not complete, the partial induction of vaginal markers in human tubal epithelium verifies the importance of mesenchymal-epithelial interactions in development of the human female reproductive tract. In a separate experiment, DES-induction of uterine epithelial progesterone receptor (PGR) and estrogen receptor 1 (ESR1) was explored in tissue recombinants composed of wild-type or Esr1KO mouse uterine mesenchyme + human fetal uterine epithelium (wt UtM+hUtE and Esr1KO UtM+hUtE). The rationale of this experiment was to determine whether DES-induction of PGR and ESR1 is mediated directly via epithelial ESR1 or indirectly (paracrine mechanism) via mesenchymal ESR1. DES-induction of uterine epithelial ESR1 and PGR in Esr1KO UtM+hUtE tissue recombinants (devoid of mesenchymal ESR1) formally eliminates the paracrine mechanism and demonstrates that DES induction of human uterine epithelial ESR1 and PGR is directly mediated via epithelial ESR1.

Epithelial oestrogen receptor α is dispensable for the development of oestrogen-induced cervical neoplastic diseases

Human papillomavirus (HPV) is required but not sufficient for cervical carcinoma (CxCa) development. Oestradiol (E₂ ) promotes CxCa development in K14E7 transgenic mice expressing the HPV16 E7 oncoprotein under the control of the keratin (K14) promoter. E₂ mainly functions through oestrogen receptor α (ERα). However, the role of ERα in human CxCa has been underappreciated largely because it is not expressed in carcinoma cells. We have shown that deletion of Esr1 (the ERα-coding gene) in the cervical stroma of K14E7 mice promotes regression of cervical intraepithelial neoplasia (CIN), the precursor lesion of CxCa. Here, we deleted Esr1 in the cervical epithelium but not in the stroma. We found that E₂ induced cervical epithelial cell proliferation in epithelial ERα-deficient mice. We also found that E₂ promoted the development of CIN and CxCa in epithelial ERα-deficient K14E7 mice and that all neoplastic epithelial cells were negative for ERα. In addition, proliferation indices were similar between ERα^- and ERα⁺ CxCa. These results indicate that epithelial ERα is not necessary for E₂ -induced CIN and CxCa. Taking these findings together, we conclude that stromal ERα rather than epithelial ERα mediates oncogenic E₂ signalling in CxCa. Our results support stromal ERα signalling as a therapeutic target for the disease. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Knockout of autophagy gene, ATG5 in mice vaginal cells abrogates cytokine response and pathogen clearance during vaginal infection of Candida albicans

The female reproductive tract (FRT) presents a unique challenge to the mucosal immune system as it needs to monitor constantly for the presence of opportunistic pathogens amidst its commensal flora. During infection, autophagy plays a critical role in pathogen clearance, presentation of antigens and production of pro-inflammatory cytokines. However, no information is available that describes the role of autophagy in mouse vaginal infection of Candida albicans. The objective of our study is to evaluate the effect of autophagy gene, ATG5 knockout in vaginal cells in response to vaginal C. albicans infection. Mice having knockout of ATG5 in the vaginal cells (PR-ATG5-KO mice) were infected intra-vaginally with the yeast form of Candida albicans. Vaginal lavages were collected once in a week until the infection was cleared. We detected the expression of autophagy marker genes (LC3, ATG5 and LAMP1) in the vaginal cells. We determined the levels of various cytokines (IL-1α, IL-1β, IL-6, IL-10, IL-17A, IL-22, IL-23p19, TNF-α and G-CSF) involved in anti-candida response. The levels of cytokines in the vaginal lavages were quantified using Aimplex Premixed analyte kit. The vaginal lavages were checked for polymorphonuclear leucocytes (PMNLs) infiltration. The candida clearance rate from the vaginal lumen was determined by Colony Forming Units (CFUs) assay. The results revealed that PR-ATG5-KO mice failed to induce the expression of LC3, ATG5 and LAMP1 indicating an impaired autophagy pathway. The levels of all the cytokines (except IL-10) in C. albicans infected PR-ATG5-KO mice were significantly reduced as compared to the wild type infected C57BL/6 mice. The number of PMNLs infiltrated into the vaginal lavages of infected PR-ATG5-KO mice was reduced. The clearance of C. albicans from the vaginal lumen was also considerably delayed in PR-ATG5-KO mice. In conclusion, the results revealed that impaired autophagy in vaginal cells influences host response during vaginal infection of C. albicans by affecting anti-Candida cytokine levels in the vaginal lavage resulting in reduction of pathogen clearance rate.

Chemodrug delivery using integrin-targeted PLGA-Chitosan nanoparticle for lung cancer therapy

In this study, we report the efficacy of RGD (arginine-glycine-aspartic acid) peptide-modified polylactic acid-co-glycolic acid (PLGA)-Chitosan nanoparticle (CSNP) for integrin α_vβ₃ receptor targeted paclitaxel (PTX) delivery in lung cancer cells and its impact on normal cells. RGD peptide-modified chitosan was synthesized and then coated onto PTX-PLGA nanoparticles prepared by emulsion-solvent evaporation. PTX-PLGA-CSNP-RGD displayed favorable physicochemical properties for a targeted drug delivery system. The PTX-PLGA-CSNP-RGD system showed increased uptake via integrin receptor mediated endocytosis, triggered enhanced apoptosis, and induced G2/M cell cycle arrest and more overall cytotoxicity than its non-targeted counterpart in cancer cells. PTX-PLGA-CSNP-RGD showed less toxicity in lung fibroblasts than in cancer cells, may be attributed to low drug sensitivity, nevertheless the study invited close attention to their transient overexpression of integrin α_vβ₃ and cautioned against corresponding uptake of toxic drugs, if any at all. Whereas, normal human bronchial epithelial (NHBE) cells with poor integrin α_vβ₃ expression showed negligible toxicity to PTX-PLGA-CSNP-RGD, at equivalent drug concentrations used in cancer cells. Further, the nanoparticle demonstrated its capacity in targeted delivery of Cisplatin (CDDP), a drug having physicochemical properties different to PTX. Taken together, our study demonstrates that PLGA-CSNP-RGD is a promising nanoplatform for integrin targeted chemotherapeutic delivery to lung cancer.

Recurrence of cervical cancer and its resistance to progestin therapy in a mouse model

Studies using K14E6/K14E7 transgenic mice expressing E6 and E7 oncoprotein of human papillomavirus type 16 (HPV16) have demonstrated that estrogen (E2) is required for the genesis and growth of cervical cancer. Our prior study using the same mouse model has showed that progestin drug medroxyprogesterone acetate (MPA) promotes regression of primary cervical cancer. In the present study, we use the same transgenic mouse model to determine whether the cancer recurs after MPA therapy. Cervical cancer recurred even if MPA treatment was continued. Unlike primary cervical cancer, the cancer recurred even in the absence of exogenous E2 when MPA treatment was ceased. Furthermore, recurrent cervical cancer did not fully regress upon MPA treatment. Our results support that MPA fails to completely eliminate primary cervical cancer cells and that remaining cancer cells grow independent of exogenous E2 and are refractory to MPA.