A majority of circadian clock genes are expressed in estrogen receptor and progesterone receptor status-dependent manner in breast cancer.

Circadian clocks, biochemical oscillators that are regulated by environmental time cues including the day/night cycle, have a central function in the majority of biological processes. The disruption of the circadian clock can alter breast biology negatively and may promote the development of breast tumors. The expression status of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) were used to classify breast cancer into different molecular subtypes such as triple-negative breast cancer (TNBC). Receptor status-dependent expression of circadian clock genes have been previously studied in breast cancer using relatively small sample sizes in a particular population. Here, using TCGA-BRCA data (n=1119), we found that the expressions of CRY1, PER1, PER2, PER3, BMAL1, CLOCK, RORA, RORB, RORC, NR1D1, NR1D2, and FBXL3 were higher in ER+ breast cancer cells compared with those of ER- status. Similarly, we showed that transcript levels of CRY2, PER1, PER2, PER3, BMAL1, RORA, RORB, RORC, NR1D1, NR1D2, and FBXL3 were higher in PR+ breast cancer cells than in PR- breast cancer cells. We report that the expressions of CRY2, PER1, BMAL1, and RORA were lower, and the expression of NR1D1 was higher, in HER2+ breast cancer cells compared with HER2- breast cancer cells. Moreover, we studied these receptor status-dependent changes in the expressions of circadian clock genes also based on the race and age of breast cancer patients. Lastly, we found that the expressions of CRY2, PER1, PER2, PER3, and CLOCK were higher in non-TNBC than in TNBC, which has the worst prognosis among subtypes. We note that our findings are not always parallel to the observations reported in previous studies with smaller sample sizes performed in different populations and organisms. Our study suggests that receptor status in breast cancer (thus, subtype of breast cancer) might be more important than previously shown in terms of its influence on the expression of circadian clock genes and on the disruption of the circadian clock, and that ER or PR might be important regulators of breast cancer chronobiology that should be taken into account in personalized chronotherapies.

PGRMC2 and HLA-G regulate immune homeostasis in a microphysiological model of human maternal-fetal membrane interface.

Chorion trophoblasts (CTCs) and immune cell-enriched decidua (DECs) comprise the maternal-fetal membrane interface called the chorio-decidual interface (CDi) which constantly gets exposed to maternal stressors without leading to labor activation. This study explored how CTCs act as a barrier at CDi. The roles of human leukocyte antigen (HLA)-G and progesterone receptor membrane component 2 (PGRMC2) in mediating immune homeostasis were also investigated. The CDi was recreated in a two-chamber microfluidic device (CDi-on-chip) with an outer chamber of primary DECs and immune cell line-derived innate immune cells and an inner chamber of wild-type or PGRMC2 or HLA-G knockout immortalized CTCs. To mimic maternal insults, DECs were treated with lipopolysaccharide, poly(I:C), or oxidative stress inducer cigarette smoke extract. Expression levels of inflammation and immunity genes via targeted RNA sequencing, production of soluble mediators, and immune cell migration into CTCs were determined. In CDi-on-chip, decidua and immune cells became inflammatory in response to insults while CTCs were refractory, highlighting their barrier function. HLA-G and PGRMC2 are found to be vital to immune homeostasis at the CDi, with PGRMC2 serving as an upstream regulator of inflammation, HLA-G expression, and mesenchymal-epithelial transition, and HLA-G serving as a frontline immunomodulatory molecule, thus preventing fetal membrane compromise.

Mechanistic insights into steroid hormone-mediated regulation of the androgen receptor gene.

Expression of the androgen receptor is key to the response of cells and tissues to androgenic steroids, such as testosterone or dihydrotestosterone, as well as impacting the benefit of hormone-dependent therapies for endocrine diseases and hormone-dependent cancers. However, the mechanisms controlling androgen receptor expression are not fully understood, limiting our ability to effectively promote or inhibit androgenic signalling therapeutically. An autoregulatory loop has been described in which androgen receptor may repress its own expression in the presence of hormone, although the molecular mechanisms are not fully understood. In this work, we elucidate the mechanisms of autoregulation and demonstrate, for the first time, that a similar repression of the AR gene is facilitated by the progesterone receptor. We show that the progesterone receptor, like the androgen receptor binds to response elements within the AR gene to effect transcriptional repression in response to hormone treatment. Mechanistically, this repression involves hormone-dependent histone deacetylation within the AR 5'UTR region and looping between sequences in intron 2 and the transcription start site (TSS). This novel pathway controlling AR expression in response to hormone stimulation may have important implications for understanding cell or tissue selective receptor signalling.

Progesterone Receptor Signaling Promotes Cancer Associated Fibroblast Mediated Tumorigenicity in ER+ Breast Cancer.

Breast cancer progression involves intricate interactions between cancer cells and the tumor microenvironment (TME). This study elucidates the critical role of progesterone receptor (PR) signaling in mediating the protumorigenic effects of cancer-associated fibroblasts (CAFs) on estrogen receptor-positive (ER+) luminal breast cancer cells. We demonstrate that CAFs produce physiologically relevant levels of estrogen and progesterone, which significantly contribute to breast cancer tumorigenicity. Specifically, CAF conditioned media (CM) promoted PR-dependent anchorage-independent growth, tumorsphere formation/stem cell expansion, and CD44 upregulation. CAF cells formed co-clusters more frequently with PR+ breast cancer cells relative to PR-null models. While both PR isoforms mediated these actions, PR-A was a dominant driver of tumorsphere formation/stemness, while PR-B induced robust CD44 expression and CAF/tumor cell co-cluster formation. CD44 knockdown impaired CAF/tumor cell co-clustering. Fibroblast growth factor 2 (FGF2), also secreted by CAFs, phosphorylated PR (Ser294) in a MAPK-dependent manner and activated PR to enhance CD44 expression and breast cancer tumorigenicity. The FGF receptor (FGFR) inhibitor PD173074 diminished CAF- and FGF2-dependent PR activation, tumorsphere formation, and co-clustering. In summary, this study reveals a novel mechanism through which stromal CAFs orchestrate elevated PR signaling in ER+ luminal breast cancer via secretion of both progesterone and FGF2, a potent activator of ERK1/2. Understanding tumor cell/TME interactions provides insights into potential therapeutic strategies aimed at disrupting PR- and/or FGF2/FGFR-dependent signaling pathways to prevent early metastasis in patients with ER+ breast cancer.

Loss of Hormone Receptor Expression after Exposure to Fluid Shear Stress in Breast Cancer Cell Lines.

Following metastatic spread, many hormone receptor positive (HR+) patients develop a more aggressive phenotype with an observed loss of the HRs estrogen receptor (ER) and progesterone receptor (PR). During metastasis, breast cancer cells are exposed to high magnitudes of fluid shear stress (FSS). Unfortunately, the role for FSS on the regulation of HR expression and function during metastasis is not fully understood. This study was designed to elucidate the impact of FSS on HR+ breast cancer. Utilizing a microfluidic platform capable of exposing breast cancer cells to FSS that mimics in situ conditions, we demonstrate the impact of FSS exposure on representative HR+ breast cancer cell lines through protein and gene expression analysis. Proteomics results demonstrated that 540 total proteins and 1473 phospho-proteins significantly changed due to FSS exposure and pathways of interest included early and late estrogen response. The impact of FSS on response to 17ß-estradiol (E2) was next evaluated and gene expression analysis revealed repression of ER and E2-mediated genes (PR and SDF1) following exposure to FSS. Western blot demonstrated enhanced phosphorylation of mTOR following exposure to FSS. Taken together, these studies provide initial insight into the effects of FSS on HR signaling in metastatic breast cancer.

Prognostic value of Maspin protein level in patients with triple negative breast cancer.

The search for prognostic markers in breast cancer has bumped into a typical feature of these tumors, intra and intertumoral heterogeneity. Changes in the expression profile, localization of these proteins or shedding to the surrounding stroma can be useful in the search for new markers. In this context, classification by molecular subtypes can bring perspectives for both diagnosis and screening for appropriate treatments. However, the Triple Negative (TN) subtype, which is already the one with the worst prognosis, lacks appropriate and consistent molecular markers. In this work, we analyzed 346 human breast cancer samples in tissue microarrays (TMA) from cases diagnosed with invasive breast carcinoma to assess the expression and localization pattern of Maspin and their correlation with clinical parameters. To complement our findings, we also used TCGA data to analyze the mRNA levels of these respective genes. Our data suggests that the TN subtype demonstrates a higher level of cytoplasmic Maspin compared to the other subtypes. Maspin transcript levels follow the same trend. However, TN patients with lower Maspin expression tend to have worse overall survival and free-survival metastasis rates. Finally, we used Maspin expression data to verify possible relationships with the clinicopathological information of our cohort. Our univariate analyses indicate that Maspin is related to the expression of estrogen receptor (ER) and progesterone receptor (PR). Furthermore, Maspin expression levels also showed correlation with Scarff-Bloom-Richardson (SBR) parameter, and stromal Maspin showed a relationship with lymph node involvement. Our data is not consistently robust enough to categorize Maspin as a prognostic marker. However, it does indicate a change in the expression profile within the TN subtype.

Transcription Factor 23 is an Essential Determinant of Murine Term Parturition.

Pregnancy involving intricate tissue transformations governed by the progesterone hormone (P4). P4 signaling via P4 receptors (PRs) is vital for endometrial receptivity, decidualization, myometrial quiescence, and labor initiation. This study explored the role of TCF23 as a downstream target of PR during pregnancy. TCF23 was found to be expressed in female reproductive organs, predominantly in uterine stromal and smooth muscle cells. Tcf23 expression was high during midgestation and was specifically regulated by P4, but not estrogen. The Tcf23 knockout (KO) mouse was generated and analyzed. Female KO mice aged 4-6 months exhibited subfertility, reduced litter size, and defective parturition. Uterine histology revealed disrupted myometrial structure, altered collagen organization, and disarrayed smooth muscle sheets at the conceptus sites of KO mice. RNA-Seq analysis of KO myometrium revealed dysregulation of genes associated with cell adhesion and extracellular matrix organization. TCF23 potentially modulates TCF12 activity to mediate cell-cell adhesion and matrix modulation in smooth muscle cells. Overall, TCF23 deficiency leads to impaired myometrial remodeling, causing parturition delay and fetal demise. This study sheds light on the critical role of TCF23 as a dowstream mediator of PR in uterine remodeling, reflecting the importance of cell-cell communication and matrix dynamics in myometrial activation and parturition.

Low androgen/progesterone or high oestrogen/androgen receptors ratio in serous ovarian cancer predicts longer survival.

The treatment of ovarian cancer (OC) remains one of the greatest challenges in gynaecological oncology. The presence of classic steroid receptors in OC makes hormone therapy an attractive option; however, the response of OC to hormone therapy is modest. Here, we compared the expression patterns of progesterone (PGR), androgen (AR) and oestrogen alpha (ERα) receptors between serous OC cell lines and non-cancer ovarian cells. These data were analysed in relation to steroid receptor expression profiles from patient tumour samples and survival outcomes using a bioinformatics approach. The results showed that ERα, PGR and AR were co-expressed in OC cell lines, and patient samples from high-grade and low-grade OC co-expressed at least two steroid receptors. High AR expression was negatively correlated, whereas ERα and PGR expression was positively correlated with patient survival. AR showed the opposite expression pattern to that of ERα and PGR in type 1 (SKOV-3) and 2 (OVCAR-3) OC cell lines compared with non-cancer (HOSEpiC) ovarian cells, with AR downregulated in type 1 and upregulated in type 2 OC. A low AR/PGR ratio and a high ESR1/AR ratio were associated with favourable survival outcomes in OC compared with other receptor ratios. Although the results must be interpreted with caution because of the small number of primary tumour samples analysed, they nevertheless suggest that the evaluation of ERα, AR and PGR by immunohistochemistry should be performed in patient biological material to plan future clinical trials.

[Application of 21-gene recurrence risk score in patients with breast cancer].

Objective: To investigate the relationship between 21-gene recurrence risk score (21-Gene RS) and the prognosis and clinicopathological features of hormone receptor (HR) positive, HER2-negative early breast cancer patients who did not receive neoadjuvant therapy. Methods: A total of 469 patients with HR positive and HER2-negative early breast cancer who received surgical treatment in the First Affiliated Hospital, Zhejiang University School of Medicine from January 2014 to October 2017 were selected. Their clinicopathological data were retrospectively analyzed. Tumor tissue samples were collected from patients, and the expression of 21-gene was detected by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR). The 21-Gene RS was calculated according to the Trial Assigning Individualized Options for Treatment (TAILORx) RS grouping and National Surgical Adjuvant Breast and Bowel Project B-20 (NSABP B-20) RS grouping principles. Patients were divided into low (21-Gene RS<11 or 21-Gene RS<18), intermediate (11≤21-Gene RS<26 or 18≤21-Gene RS<31) and high (21-Gene RS≥26 or 21-Gene RS≥31) risk groups, and the clinicopathological features and prognostic differences of patients in different risk groups were compared. Statistical data were compared by chi-square test. Survival analysis was performed using Kaplan-Meier curve analysis and the differences between groups were compared using Log-rank test. Multivariate analysis was conducted by COX regression analysis. Results: Based on TAILORx RS grouping, the proportions of low-risk, intermediate-risk and high-risk groups among the 469 patients were 18.8% (88/469), 48.2% (226/469) and 33.0% (155/469), respectively. Based on NSABP B-20 RS grouping, the proportion of low-risk, intermediate-risk and high-risk groups were 43.1% (202/469), 37.5% (176/469) and 19.4% (91/469), respectively. The association of 21-Gene RS with histological grading, luminal typing, Ki-67 expression, and chemotherapy and treatment modalities were statistically significant (P<0.05) regardless of TAILORx RS grouping or NSABP B-20 RS grouping. Kaplan-Meier survival curve suggested poor prognosis in high-risk group (P<0.05, Log-rank test). Multivariate COX regression analysis showed that surgical method and 21-Gene RS were risk factors affecting the prognosis of patients. Conclusions: 21-Gene RS is significantly associated with the prognosis of patients with HR-positive, HER2-negative, early-stage breast cancer not receiving neoadjuvant therapy, as well as with their clinicopathological characteristics such as patients' histologic grade, luminal typing, Ki-67 expression, and whether or not they are treated with chemotherapy or other treatment modalities.The 21-Gene RS threshold of 11 and 26 or 18 and 31 can be used to grade the prognosis in Chinese patients with early-stage breast cancer. More researches are needed to guide the selection of postoperative adjuvant therapy for patients with HR-positive and HER2-negative early-stage breast cancer.

Genomic profiling and comparative analysis of male versus female metastatic breast cancer across subtypes.

BACKGROUND: Male breast cancer (MaBC) has limited data on genomic alterations. We aimed to comprehensively describe and compare MaBC's genomics with female breast cancer's (FBC) across subtypes. METHODS: Using genomic data from Foundation Medicine, we categorized 253 MaBC into estrogen receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative (n = 210), ER-positive/HER2-positive (n = 22) and triple-negative (n = 20). One ER-negative/HER2-positive case was excluded due to n-of-1. The genomics of the final MaBC cohort (n = 252) were compared to a FBC cohort (n = 2708) stratified by molecular subtype, with adjusted p-values. In the overall MaBC and FBC cohorts, we compared mutational prevalence in cancer susceptibility genes (CSG) (ATM/BRCA1/BRCA2/CHEK2/PALB2). RESULTS: Comparing ER-positive/HER2-negative cases, MaBc had increased alterations in GATA3 (26.2% vs. 15.9%, p = 0.005), BRCA2 (13.8% vs. 5.3%, p < 0.001), MDM2 (13.3% vs. 6.14%, p = 0.004) and CDK4 (7.1% vs. 1.8%, p < 0.001); and decreased frequency of TP53 (11.0% vs. 42.6%, p < 0.001) and ESR1 mutations (5.7% vs. 14.6%, p < 0.001). Comparing ER-positive/HER2-positive cases, MaBC had increased short variants in ERBB2 (22.7% vs. 0.6%, p = 0.002), GATA3 (36.3% vs. 6.2%, p = 0.004), and MDM2 (36.3% vs. 4.9%, p = 0.002); decreased frequency of TP53 alterations was seen in MaBC versus FBC (9.1% vs. 61.7%, p < 0.001). Within triple-negative cases, MaBC had decreased alterations in TP53 compared to FBC (25.0% vs. 84.4%, p < 0.001). MaBC had higher frequency of CSG variants than FBC (22.6% vs. 14.6%, p < 0.05), with increased BRCA mutations in MaBC (14.6% vs. 9.1%, p < 0.05). CONCLUSIONS: Although MaBC and FBC share some common alterations, our study revealed several important differences relevant to tumor biology and implications for targeted therapies.

Transcriptomic Profile of Breast Tissue of Premenopausal Women Following Treatment with Progesterone Receptor Modulator: Secondary Outcomes of a Randomized Controlled Trial.

Progesterone receptor antagonism is gaining attention due to progesterone's recognized role as a major mitogen in breast tissue. Limited but promising data suggest the potential efficacy of antiprogestins in breast cancer prevention. The present study presents secondary outcomes from a randomized controlled trial and examines changes in breast mRNA expression following mifepristone treatment in healthy premenopausal women. We analyzed 32 paired breast biopsies from 16 women at baseline and after two months of mifepristone treatment. In total, 27 differentially expressed genes were identified, with enriched biological functions related to extracellular matrix remodeling. Notably, the altered gene signature induced by mifepristone in vivo was rather similar to the in vitro signature. Furthermore, this gene expression signature was linked to breast carcinogenesis and notably linked with progesterone receptor expression status in breast cancer, as validated in The Cancer Genome Atlas dataset using the R2 platform. The present study is the first to explore the breast transcriptome following mifepristone treatment in normal breast tissue in vivo, enhancing the understanding of progesterone receptor antagonism and its potential protective effect against breast cancer.

Genome-wide association meta-analysis identifies five loci associated with postpartum hemorrhage.

Bleeding in early pregnancy and postpartum hemorrhage (PPH) bear substantial risks, with the former closely associated with pregnancy loss and the latter being the foremost cause of maternal death, underscoring the severe impact on maternal-fetal health. We identified five genetic loci linked to PPH in a meta-analysis. Functional annotation analysis indicated candidate genes HAND2, TBX3 and RAP2C/FRMD7 at three loci and showed that at each locus, associated variants were located within binding sites for progesterone receptors. There were strong genetic correlations with birth weight, gestational duration and uterine fibroids. Bleeding in early pregnancy yielded no genome-wide association signals but showed strong genetic correlation with various human traits, suggesting a potentially complex, polygenic etiology. Our results suggest that PPH is related to progesterone signaling dysregulation, whereas early bleeding is a complex trait associated with underlying health and possibly socioeconomic status and may include genetic factors that have not yet been identified.

How Progesterone Receptor Expression Impacts Platinum Sensitivity in Ovarian Clear Cell Carcinoma: Insights from Clinical and Experimental Perspectives.

Ovarian clear cell carcinoma (OCCC) is often considered a relatively platinum-resistant malignancy. The aim of this study was to explore the influence of progesterone receptor (PR) expression levels on platinum sensitivity and survival outcomes in people with OCCC. A retrospective analysis was conducted with 80 people with OCCC who underwent surgery followed by adjuvant chemotherapy. PR expression was assessed via immunohistochemical (IHC) staining and quantified using the H score. The platinum sensitivity and survival outcomes of patients with weak and strong PR expression were compared. Additionally, cisplatin viability and migration experiments were conducted with OCCC cell lines (ES-2 and TOV-21G) with varying PR isoform expressions. Among the 80 patients, 62 were classified as having platinum-sensitive disease, while 18 had platinum-resistant disease. The mean total PR H- score of platinum-sensitive tumors was significantly higher than that of platinum-resistant tumors (p = 0.002). Although no significant differences in progression-free and overall survival were observed between patients with high and low PR expression, those with high PR expression tended to have longer survival. While PR protein was only weakly detectable in ES-2 and TOV-21G cells, a transfection of the PR-A or PR-B gene resulted in a strong expression of PR-A or PR-B, which led to significantly reduced proliferation and migration in ES-2 and TOV-21G cells. Furthermore, overexpression of PR-A or PR-B enhanced cisplatin cytotoxicity in these cell lines. In conclusion, strong PR expression was associated with improved platinum sensitivity and survival outcomes, consistent with our experimental findings. The potential of PR as a tumor sensitizer to cisplatin in OCCC warrants further investigation.

Metformin Prevents Tumor Cell Growth and Invasion of Human Hormone Receptor-Positive Breast Cancer (HR+ BC) Cells via FOXA1 Inhibition.

Women with type 2 diabetes (T2D) have a higher risk of being diagnosed with breast cancer and have worse survival than non-diabetic women if they do develop breast cancer. However, more research is needed to elucidate the biological underpinnings of these relationships. Here, we found that forkhead box A1 (FOXA1), a forkhead family transcription factor, and metformin (1,1-dimethylbiguanide hydrochloride), a medication used to treat T2D, may impact hormone-receptor-positive (HR+) breast cancer (BC) tumor cell growth and metastasis. Indeed, fourteen diabetes-associated genes are highly expressed in only three HR+ breast cancer cell lines but not the other subtypes utilizing a 53,805 gene database obtained from NCBI GEO. Among the diabetes-related genes, FOXA1, MTA3, PAK4, FGFR3, and KIF22 were highly expressed in HR+ breast cancer from 4032 breast cancer patient tissue samples using the Breast Cancer Gene Expression Omnibus. Notably, elevated FOXA1 expression correlated with poorer overall survival in patients with estrogen-receptor-positive/progesterone-receptor-positive (ER+/PR+) breast cancer. Furthermore, experiments demonstrated that loss of the FOXA1 gene inhibited tumor proliferation and invasion in vitro using MCF-7 and T47D HR+ breast cancer cell lines. Metformin, an anti-diabetic medication, significantly suppressed tumor cell growth in MCF-7 cells. Additionally, either metformin treatment or FOXA1 gene deletion enhanced tamoxifen-induced tumor growth inhibition in HR+ breast cancer cell lines within an ex vivo three-dimensional (3D) organoid model. Therefore, the diabetes-related medicine metformin and FOXA1 gene inhibition might be a new treatment for patients with HR+ breast cancer when combined with tamoxifen, an endocrine therapy.

Differential expression of NAT1 pharmacogene in hormone receptor positive vs. negative female breast tumors may affect drug treatment.

Studies have reported overexpression of NAT1 gene for xenobiotic metabolizing arylamine N -acetyltransferase type 1 in estrogen receptor positive breast tumors, and this association has been linked to patient chemoresistance and response to tamoxifen. We probed the expression of NAT1 , using quantitative reverse transcription PCR to screen clinically characterized breast cancer tissue cDNA arrays. Primers detecting all NAT1 alternative transcripts were used, and the protocol and results are reported according to consensus guidelines. The clinical information about 166 tumor samples screened is provided, including tumor stage, estrogen and progesterone receptor status and HER2 expression. NAT1 was found to be significantly ( P  < 0.001) upregulated in hormone receptor positive vs. negative tumors. No correlation was apparent between NAT1 and tumor stage or HER2 expression. Our findings demonstrate a strong correlation between the expression of NAT1 and steroid hormone receptors in breast tumors, supporting its possible utility as a pharmacogenetic biomarker or drug target. Of the two polymorphic NAT genes, NAT1 is the one primarily expressed in breast tissue, and is subjected to regulation by two differential promoters and more than one polyadenylation signal. Hormonal factors may enhance NAT1 gene expression at the transcriptional or epigenetic level, and tamoxifen has additionally been shown to inhibit NAT1 enzymatic activity. The outcome of tamoxifen treatment is also more favorable in patients with NAT1 overexpressing tumors. The study adds to the growing body of evidence implicating NAT1 in breast cancer and its pharmacological treatment.

Half of most frequently mutated genes in breast cancer are expressed differentially between premenopausal and postmenopausal breast cancer patients.

Breast cancer has distinct causes and molecular characteristics at premenopausal and postmenopausal ages. The age-standardized incidence rate for postmenopausal breast cancer is more than 10 times higher than in premenopausal breast cancer. Here, we showed that the expression of 10 out of 20 most frequently mutated genes in breast cancer (namely, PIK3CA, CDH1, MUC16, PTEN, FAT3, FAT1, SPEN, ARID1A, LRP1B and RUNX1) is higher in premenopausal women with breast cancer than in postmenopausal women with breast cancer. The most significant differences in the expression in terms of menopause status were observed for RUNX1 and FAT1. Furthermore, we found that the majority of these 10 genes also show ER (estrogen receptor) or PR (progesterone receptor) status-dependent expression in both premenopausal and postmenopausal breast cancer patients. Unlike what we observed in the case of ER or PR status, the expression of most of these genes does not change depending on HER2 (human epidermal growth factor receptor 2) status in both premenopausal and postmenopausal breast cancer patients. Combined, our analysis suggests that menopause status might influence the expression of most frequently mutated genes in breast cancer, and that the most of these genes whose expression differ between pre- and post-menopausal women with breast cancer also show ER or PR status-dependent expression in women with breast cancer.

Decline in corepressor CNOT1 in the pregnant myometrium near term impairs progesterone receptor function and increases contractile gene expression.

Progesterone (P4), acting via its nuclear receptor (PR), is critical for pregnancy maintenance by suppressing proinflammatory and contraction-associated protein (CAP)/contractile genes in the myometrium. P4/PR partially exerts these effects by tethering to NF-κB bound to their promot-ers, thereby decreasing NF-κB transcriptional activity. However, the underlying mechanisms whereby P4/PR interaction blocks proinflammatory and CAP gene expression are not fully understood. Herein, we characterized CCR-NOT transcription complex subunit 1 (CNOT1) as a corepressor that also interacts within the same chromatin complex as PR-B. In mouse myome-trium increased expression of CAP genes Oxtr and Cx43 at term coincided with a marked decline in expression and binding of CNOT1 to NF-κB-response elements within the Oxtr and Cx43 promoters. Increased CAP gene expression was accompanied by a pronounced decrease in enrichment of repressive histone marks and increase in enrichment of active histone marks to this genomic region. These changes in histone modification were associated with changes in expression of corresponding histone modifying enzymes. Myometrial tissues from P4-treated 18.5 dpc pregnant mice manifested increased Cnot1 expression at 18.5 dpc, compared to vehicle-treated controls. P4 treatment of PR-expressing hTERT-HM cells enhanced CNOT1 expression and its recruitment to PR bound NF-κB-response elements within the CX43 and OXTR promoters. Furthermore, knockdown of CNOT1 significantly increased expression of contractile genes. These novel findings suggest that decreased expression and DNA-binding of the P4/PR-regulated transcriptional corepressor CNOT1 near term and associated changes in histone modifications at the OXTR and CX43 promoters contribute to the induction of myometrial contractility leading to parturition.

A Novel Receptor Binding Progesterone, a Possible Transregulation Mechanism in the Rhipicephalus microplus-Host Interaction.

BACKGROUND: Hormone receptors exert their function through binding with their ligands, which results in cellular signaling activation mediated by genomic or non-genomic mechanisms. The intrinsic molecular communication of tick Rhipicephalus microplus and its host Bos taurus comprises an endocrine regulation involving hormones. In the present study, we performed a molecular and in silico analysis of a Membrane Associated Progesterone Receptor in R. microplus (RmMAPRC). METHODS: The RmMAPRC protein sequence was analyzed with bioinformatics tools, and its structure was characterized by three-dimensional (3D) modeling and molecular docking. A semi-quantitative reverse transcription and polymerase chain reaction (sqRT-PCR) assessed the RmMAPRC gene presence and relative expression in tick organs and embryonic cells. RESULTS: RmMAPRC relative expression in salivary glands, ovaries, and embryonic cells showed overexpression of 3%, 13%, and 24%, respectively. Bioinformatic analysis revealed that RmMAPRC corresponded to a Progesterone Receptor Membrane Component 1 (RmPGRMC1) of ~23.7 kDa, with an N-terminal transmembrane domain and a C-terminal Cytochrome b5-like heme/steroid binding domain. The docking results suggest that RmPGRMC1 could bind to progesterone (P4), some progestins, and P4 antagonists. The phylogenetic reconstruction showed that Rhipicephalus spp. MAPRC receptors were clustered in a clade that includes R. appendiculatus, R. sanguineus, and R. microplus (RmMAPRC), and mammals and helminths MAPRC receptors clustered in two separated clades away from ticks. CONCLUSIONS: The presence of RmPGRMC1 highlights the importance of transregulation as a conserved adaptive mechanism that has succeeded for arthropod parasites, making it a target for tick control.

Generation of Oviductal Glycoprotein 1 Cre Mouse Model for the Study of Secretory Epithelial Cells of the Oviduct.

The epithelial cell lining of the oviduct plays an important role in oocyte pickup, sperm migration, preimplantation embryo development, and embryo transport. The oviduct epithelial cell layer comprises ciliated and nonciliated secretory cells. The ciliary function has been shown to support gamete and embryo movement in the oviduct, yet secretory cell function has not been well characterized. Therefore, our goal was to generate a secretory cell-specific Cre recombinase mouse model to study the role of the oviductal secretory cells. A knock-in mouse model, Ovgp1Cre:eGFP, was created by expressing Cre from the endogenous Ovgp1 (oviductal glycoprotein 1) locus, with enhanced green fluorescent protein (eGFP) as a reporter. EGFP signals were strongly detected in the secretory epithelial cells of the oviducts at estrus in adult Ovgp1Cre:eGFP mice. Signals were also detected in the ovarian stroma, uterine stroma, vaginal epithelial cells, epididymal epithelial cells, and elongated spermatids. To validate recombinase activity, progesterone receptor (PGR) expression was ablated using the Ovgp1Cre:eGFP; Pgrf/f mouse model. Surprisingly, the deletion was restricted to the epithelial cells of the uterotubal junction (UTJ) region of Ovgp1Cre:eGFP; Pgrf/f oviducts. Deletion of Pgr in the epithelial cells of the UTJ region had no effect on female fecundity. In summary, we found that eGFP signals were likely specific to secretory epithelial cells in all regions of the oviduct. However, due to a potential target-specific Cre activity, validation of appropriate recombination and expression of the gene(s) of interest is absolutely required to confirm efficient deletion when generating conditional knockout mice using the Ovgp1Cre:eGFP line.

Bisphenol-A in Drinking Water Accelerates Mammary Cancerogenesis and Favors an Immunosuppressive Tumor Microenvironment in BALB-neuT Mice.

Bisphenol-A (BPA), a synthetic compound ubiquitously present in the environment, can act as an endocrine disruptor by binding to both canonical and non-canonical estrogen receptors (ERs). Exposure to BPA has been linked to various cancers, in particular, those arising in hormone-targeted tissues such as the breast. In this study, we evaluated the effect of BPA intake through drinking water on ErbB2/neu-driven cancerogenesis in BALB-neuT mice, transgenic for a mutated ErbB2/neu receptor gene, which reproducibly develop carcinomas in all mammary glands. In this model, BPA accelerated mammary cancerogenesis with an increase in the number of tumors per mouse and a concurrent decrease in tumor-free and overall survival. As assessed by immunohistochemistry, BALB-neuT tumors were ER-negative but expressed high levels of the alternative estrogen receptor GPR30, regardless of BPA exposure. On the other hand, BPA exposure resulted in a marked upregulation of progesterone receptors in preinvasive tumors and of Ki67, CD31, and phosphorylated Akt in invasive tumors. Moreover, based on several infiltration markers of immune cells, BPA favored an immunosuppressive tumor microenvironment. Finally, in vitro cell survival studies performed on a cell line established from a BALB-neuT breast carcinoma confirmed that BPA's impact on cancer progression can be particularly relevant after chronic, low-dose exposure.