A Hypothetical Model Suggesting Some Possible Ways That the Progesterone Receptor May Be Involved in Cancer Proliferation.

Cancer and the fetal-placental semi-allograft share certain characteristics, e.g., rapid proliferation, the capacity to invade normal tissue, and, related to the presence of antigens foreign to the host, the need to evade immune surveillance. Many present-day methods to treat cancer use drugs that can block a key molecule that is important for one or more of these characteristics and thus reduce side effects. The ideal molecule would be one that is essential for both the survival of the fetus and malignant tumor, but not needed for normal cells. There is a potential suitable candidate, the progesterone induced blocking factor (PIBF). The parent 90 kilodalton (kDa) form seems to be required for cell-cycle regulation, required by both the fetal-placental unit and malignant tumors. The parent form may be converted to splice variants that help both the fetus and tumors escape immune surveillance, especially in the fetal and tumor microenvironment. Evidence suggests that membrane progesterone receptors are involved in PIBF production, and indeed there has been anecdotal evidence that progesterone receptor antagonists, e.g., mifepristone, can significantly improve longevity and quality of life, with few side effects.

The Immunology of Hormone Receptor Positive Breast Cancer.

Immune checkpoint blockade (ICB) has revolutionized the treatment of cancer patients. The main focus of ICB has been on reinvigorating the adaptive immune response, namely, activating cytotoxic T cells. ICB has demonstrated only modest benefit against advanced breast cancer, as breast tumors typically establish an immune suppressive tumor microenvironment (TME). Triple-negative breast cancer (TNBC) is associated with infiltration of tumor infiltrating lymphocytes (TILs) and patients with TNBC have shown clinical responses to ICB. In contrast, hormone receptor positive (HR+) breast cancer is characterized by low TIL infiltration and minimal response to ICB. Here we review how HR+ breast tumors establish a TME devoid of TILs, have low HLA class I expression, and recruit immune cells, other than T cells, which impact response to therapy. In addition, we review emerging technologies that have been employed to characterize components of the TME to reveal that tumor associated macrophages (TAMs) are abundant in HR+ cancer, are highly immune-suppressive, associated with tumor progression, chemotherapy and ICB-resistance, metastasis and poor survival. We reveal novel therapeutic targets and possible combinations with ICB to enhance anti-tumor immune responses, which may have great potential in HR+ breast cancer.

Identification of Interleukin-9 Producing Immune Cells in Endometrial Carcinoma and Establishment of a Prognostic Nomogram.

Background: Interleukin-9 (IL9) plays a critical role in immunity and the pathogenesis of endometrial cancer (EC), especially endometrioid EC (EEC). This study aimed to identify the IL9+ immune cell subsets and their pleiotropic functions and establish an optimized prognostic nomogram towards the promotion of personalized treatment of EEC. Methods: 1,417 EC patients were involved in the present study. 143 patients from the tertiary gynecology centers in Shanghai between 2013 and 2019 were recruited, and the study protocol was approved by the Institutional Review Board (IRB) of Shanghai First Maternity and Infant Hospital. The genomic data of the other 1,274 patients were extracted from the TCGA and the MSKCC datasets, respectively. Immune and stromal scores were calculated using the ESTIMATE R tool, and the tumor infiltration of immune cells was analyzed using the TIMER platform. Metascape and GEPIA datasets were used for bioinformatic analysis. P < 0.05 was considered statistically significant. All statistical analyses were performed with GraphPad Prism and R studio. Results: 552 genes that were correlated with leukocyte infiltration, lymphocyte activation, and regulation of innate immune response were up-regulated in the high immune score group. More IL9+ cell infiltration was detected in the highly and moderately differentiated EC (p = 0.04). High IL9+ lymphocyte infiltration was related to a better overall survival (p = 0.0027). IL9 positive cell clusters included ILC2s, Vδ2 γδT cells, mast cells, macrophages, and Th9 cells. Parameters such as FIGO stage, IL9 score, Vδ2 + γδT cell infiltration, classification of differentiation, and diabetes mellitus were assigned a weighted number of points in the nomogram for a specific predicted 3-, 5- and 10-year overall survival (OS). IL9-IL9R axis played a vital role in EEC, IL9R positive cell subgroups were also identified, and the related function was analyzed in the present study. Additionally, PR (Progesterone Receptor, or PGR) expression was relevant to a higher density of IL9+ lymphocyte infiltration. However, PGRMC1 (Progesterone Receptor Membrane Component 1) was negatively relevant to IL9R (p = 4.26e-8). Conclusion: We observed a significant infiltration of IL9+ cells and the overrepresentation of IL-9R in tissue specimens of patients in EC cases. The nomogram incorporating the IL9 could accurately predict individualized survival probability in EEC. Additionally, this study not only established a prognostic nomogram but also assist in the firmer understanding of the relevance of the IL9-IL9R axis and IL9-producing cells in EC immunity.

Correlation study between the magnetic resonance imaging features of breast cancer and expression of immune molecular subtypes.

OBJECTIVE: To investigate the correlation between breast cancer magnetic resonance imaging features and immune molecular subtypes. PATIENTS AND METHODS: A total of 129 breast cancer patients were selected as the research object. All the patients were diagnosed by histopathology. All of them had breast magnetic resonance imaging and examination data of immunohistochemical (IHC) ER, PR, HER-2, and Ki-67. The correlation of breast cancer magnetic resonance imaging features with different immune molecular subtypes was retrospectively analyzed. RESULTS: Breast cancer is divided into different molecular subtypes. There were 72 cases with Luminal A type (55.81%), 20 cases with Luminal B type (15.50%), 14 cases with HER-2+ type (HER-2 type for over-expression) (10.85%), 23 cases with TNBC type (ER, PR and HER-2 were negative) (17.84%). The magnetic resonance imaging features of breast cancer were included, the post-enhanced morphology, margins, internal enhancement features, time-signal intensity curve (TIC) and molecular subtype expression of lesions were significantly correlated with the immune molecular subtypes (C=0.602, 0.439, 0.350 and 0.407, p=0.000, 0.000, 0.006 and 0.000). Lesion morphology: Luminal A type was mainly oval, accounting for 76.39% (55/76). Luminal B type and HER-2+ type was mainly irregular, accounting for 75.00% (15/20) and 64.29% (9/14) respectively. TNBC type was mainly shown as lobulation, accounting for 60.87% (14/23). Margin of the lesion: Luminal A type was mainly smooth margin, accounting for 73.61% (53/72). Luminal B type and TNBC type were mainly irregular margin, accounting for 70.00% (14/20) and 56.52% (13/23) respectively. The margin of HER-2+ type was mainly spiculation, accounting for 64.29% (9/14). The internal enhancement features: Luminal A type was mainly even enhancement, accounting for 62.50% (45/72). Luminal B type and HER-2+ type were mainly heterogeneous enhancement, accounting for 65.00% (13/20) and 64.29% (9/14) respectively. TNBC type was mainly annular enhancement, accounting for 73.91% (17/23). TIC type: Luminal A type was mainly Type II, accounting for 66.67% (48/72). Luminal B, HER-2+ type and TNBC type was mainly Type III, accounting for 70.00% (14/20), 64.29% (9/14) and 60.87% (14/23) respectively. The clinical signs include painless breast lumps, bloody breast discharge, and orange peel-like skin changes, nipple retraction and nipple elevation. There is no significant correlation between the above signs and the expression of molecular subtypes (C=0.014, 0.129, 0.154, 0.097 and 0.057, p=0.999, 0.533, 0.447, 0.747 and 0.935 respectively), the difference is not statistically significant (p>0.05). CONCLUSIONS: The characteristics of breast cancer magnetic resonance imaging was certainly correlated with the expression of immune molecular subtypes. The breast cancer molecular subtypes can be predicted by the imaging signs, which can provide valuable information for preoperative neoadjuvant treatment of breast cancer.

Discordance of immunohistochemical markers between primary and recurrent or metastatic breast cancer: A retrospective analysis of 107 cases.

There is a discordance in the immunohistochemical markers between primary breast cancer and recurrent or metastatic breast cancer. This study aimed to assess the recent trends and prognostic features in the treatment of recurrent or metastatic breast cancerOverall, 107 patients were identified from January 2001 to August 2018 at the Peking Union Medical College Hospital, Beijing, and People's Republic of China to obtain a cohort of breast carcinoma patients who were confirmed to have recurrent or metastatic breast cancer by histopathology. We evaluated patient and tumor characteristics and examined the relationships between these factors and prognosis.The estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2) positivity, and Ki67 index in primary breast cancer were 63.6% (68/107), 58.9% (63/107), 19.8% (21/106) and 75.8% (75/99), respectively, while those in recurrent or metastatic lesions were 60.6% (65/107) (P = .672), 46.7% (50/107) (P = 0.013), 23.8% (25/105) (P = 0.482)and 83.5%(81/97)(P = 0.178), respectively. The discordance rate of HER2 expression was 10.6% (11/104), while that of PR expression was 23.3% (21/90). HER2 was the most stable biomarker. The discordance rates for luminal A and HER2 were as high as 100% and 25%, respectively, while the luminal B and triple negative values were as low as 8.3% and 5.3%, respectively.ER and PR positivity and the Ki-67 index tended to increase due to recurrence or metastases; however, the discordance for PR and Ki-67 was high. PR is more variable than ER in the expression of primary and recurrent or metastatic breast cancer. The expression of HER2 receptor was the most stable and the discordance rate of triple negative breast cancer was the lowest. Therefore, although changes in biomarkers are due to recurrence or metastasis, pathological confirmation and exploration of markers are very important.

The GATA3 X308_Splice breast cancer mutation is a hormone context-dependent oncogenic driver.

As the catalog of oncogenic driver mutations is expanding, it becomes clear that alterations in a given gene might have different functions and should not be lumped into one class. The transcription factor GATA3 is a paradigm of this. We investigated the functions of the most common GATA3 mutation (X308_Splice) and five additional mutations, which converge into a neoprotein that we called "neoGATA3," associated with excellent prognosis in patients. Analysis of available molecular data from >3000 breast cancer patients revealed a dysregulation of the ER-dependent transcriptional response in tumors carrying neoGATA3-generating mutations. Mechanistic studies in vitro showed that neoGATA3 interferes with the transcriptional programs controlled by estrogen and progesterone receptors, without fully abrogating them. ChIP-Seq analysis indicated that ER binding is reduced in neoGATA3-expressing cells, especially at distal regions, suggesting that neoGATA3 interferes with the fine tuning of ER-dependent gene expression. This has opposite outputs in distinct hormonal context, having pro- or anti-proliferative effects, depending on the estrogen/progesterone ratio. Our data call for functional analyses of putative cancer drivers to guide clinical application.

External quality assessment (EQA) program for the immunohistochemical detection of ER, PR and Ki-67 in breast cancer: results of an interlaboratory reproducibility ring study in China.

BACKGROUND: An External Quality Assessment (EQA) program was developed to investigate the status of estrogen receptor (ER), progesterone receptor (PR), and Ki-67 immunohistochemical (IHC) detection in breast cancer and to evaluate the reproducibility of staining and interpretation in 44 pathology laboratories in China. METHODS: This program was implemented through three specific steps. In study I, three revising centres defined the reference value for 11 sections. In study II, 41 participating centres (PC) stained and interpreted 11 sections by their own daily practice IHC protocols. In study III, all cases received second interpretation opinions. RESULTS: The stained slides of 44 laboratories were up to the interpretation standard. The overall interpretation concordance rate of this study was over 90%. A perfect agreement was reached among the PCs for the cases with ER+ and PR+ > 50% and Ki-67 > 30%, whereas a moderate agreement was observed for intermediate categories. After second interpretations, the misclassification rates for ER were reduced by 12.20%, for PR were reduced by 17.07%, and for Ki-67 were reduced by 4.88%. Up to 31 PCs observed a benefit from the second opinion strategy. CONCLUSIONS: This project is the first EQA study performed on a national scale for assessment of ER, PR and Ki-67 status by IHC in China. In the whole IHC evaluation process, the intermediate categories were less reproducible than those with high expression rates. Second opinions can significantly improve the diagnostic agreement of pathologists' interpretations.

Progesterone Receptor Attenuates STAT1-Mediated IFN Signaling in Breast Cancer.

Why some tumors remain indolent and others progress to clinical relevance remains a major unanswered question in cancer biology. IFN signaling in nascent tumors, mediated by STAT1, is a critical step through which the surveilling immune system can recognize and destroy developing tumors. In this study, we have identified an interaction between the progesterone receptor (PR) and STAT1 in breast cancer cells. This interaction inhibited efficient IFN-induced STAT1 phosphorylation, as we observed a decrease in phospho-STAT1 in response to IFN treatment in PR-positive breast cancer cell lines. This phenotype was further potentiated in the presence of PR ligand. In human breast cancer samples, PR-positive tumors exhibited lower levels of phospho-STAT1 as compared with their PR-negative counterparts, indicating that this phenotype translates to human tumors. Breast cancer cells lacking PR exhibited higher levels of IFN-stimulated gene (ISG) RNA, the transcriptional end point of IFN activation, indicating that unliganded PR alone could decrease transcription of ISGs. Moreover, the absence of PR led to increased recruitment of STAT1, STAT2, and IRF9 (key transcription factors necessary for ISG transcription) to ISG promoters. These data indicate that PR, both in the presence and absence of ligand, attenuates IFN-induced STAT1 signaling, culminating in significantly abrogated activation of genes transcribed in response to IFNs. PR-positive tumors may use downregulation of STAT1-mediated IFN signaling to escape immune surveillance, leading to the development of clinically relevant tumors. Selective immune evasion of PR-positive tumors may be one explanation as to why over 65% of breast cancers are PR positive at the time of diagnosis.

Epitope mapping of anti-PGRMC1 antibodies reveals the non-conventional membrane topology of PGRMC1 on the cell surface.

Progesterone receptor membrane component1 (PGRMC1) is a heme-binding protein involved in cancers and Alzheimer's disease. PGRMC1 consists of a short N-terminal extracellular or luminal domain, a single membrane-spanning domain, and a long cytoplasmic domain. Previously, we generated two monoclonal antibodies (MAbs) 108-B6 and 4A68 that recognize cell surface-expressed PGRMC1 (csPGRMC1) on human pluripotent stem cells and some cancer cells. In this study, flow cytometric analysis found that an anti-PGRMC1 antibody recognizing the N-terminus of PGRMC1 could not bind to csPGRMC1 on cancer cells, and 108-B6 and 4A68 binding to csPGRMC1 was inhibited by trypsin treatment, suggesting that the epitopes of 108-B6 and 4A68 are trypsin-sensitive. To examine the epitope specificity of 108-B6 and 4A68, glutathione-S-transferase (GST)-fused PGRMC1 mutants were screened to identify the epitopes targeted by the antibodies. The result showed that 108-B6 and 4A68 recognized C-terminal residues 183-195 and 171-182, respectively, of PGRMC1, where trypsin-sensitive sites are located. A polyclonal anti-PGRMC1 antibody raised against the C-terminus of PGRMC1 could also recognized csPGRMC1 in a trypsin-sensitive manner, suggesting that the C-terminus of csPGRMC1 is exposed on the cell surface. This finding reveals that csPGRMC1 has a non-conventional plasma membrane topology, which is different from that of intracellular PGRMC1.

Review of immunohistochemical typing of endometrial carcinoma at the Lagos University Teaching Hospital.

BACKGROUND: Categorization of endometrial carcinomas as type I and II provides useful insights into their different risk factors, pathogenesis and biologic behaviours. AIM: To determine the immunohistochemical classifications of endometrial carcinomas in Nigerian women. DESIGN: A retrospective review of histopathologic slides of cases of endometrial carcinomas seen at the Lagos University Teaching Hospital (LUTH) over a 5-year period. The slides were reviewed, and the diagnoses made according to the WHO nomenclature. The classification of endometrial carcinomas into Type I and II was made by immunohistochemistry using antibodies to ER, PR, p53 and Ki-67. RESULTS: Eight cases of endometrial adenocarcinoma were reported accounting for 53.3% of all endometrial malignancies. Of these, only 1 case showed the classic type I immunophenotype while type II staining pattern was seen in 4 cases. The remaining 3 cases had equivocal immunophenotypes: one was p53+ but showed ER+, PR+ and high Ki-67 index; the second was p53-, ER+, PR+ but had a high Ki-67 expression; while the last was p53-, but ER-, PR- and had high Ki-67 expression. CONCLUSION: Endometrial carcinomas in Nigerian women are more likely to be type II carcinomas. A reasonable proportion of the cases were equivocal thus requiring further categorization with molecular studies.

Tumor-Infiltrating Lymphocytes in Breast Cancer. Association with Clinical and Pathological Parameters.

In patients with primary resectable breast cancer, a positive correlation between the age and the count of CD16+ lymphocytes and a negative correlation of this parameter with the number of regulatory CD4+CD25+CD127- cells and proliferative activity of Ki-67 tumor cells were revealed. Higher level of Ki-67 was associated with reduced number of effector lymphocytes (CD8+ and CD16+) and elevated content of regulatory CD8+CD11b-CD28- T cells. The absence of expression of estrogen receptors was associated with reduced cytotoxic potential of CD8+ T cell in comparison with ER+ breast cancer. The percentage of CD8+ lymphocytes (CD3+CD8+ and CD8+CD11b+CD28+) among lymphocytes infiltrating the tumor was higher in PR+ breast cancer than in PR- tumors. With increasing the tumor load, the number of lymphocytes expressing CD16 marker and their cytotoxic potential decreased.

Stability of oestrogen and progesterone receptor antigenicity in formalin-fixed paraffin-embedded breast cancer tissue over time.

Use of archived formalin-fixed paraffin-embedded (FFPE) tissue is a standard method for evaluation of proposed prognostic and predictive tumour markers. However, little is known of the preservation of biomarker expression in old FFPE tumour blocks. We investigate the quality of immunohistochemical (IHC) oestrogen (ER) and progesterone receptor (PR) evaluation in FFPE tissue over time (1978-2000) using a large breast cancer tissue microarray (N = 573) with access to receptor analyses in cytosol (CYT) at diagnosis, coexpression of other biomarkers and follow-up data. We found a good correlation between ER analysed with CYT at diagnosis and ER analysed with IHC in archived FFPE tissue from the same tumour. ER evaluation did not seem to be affected by tissue storage time. Nor was there any time-dependent difference in ERIHC correlation with other biomarkers (HER2, Ki67) or survival. Discordant cases were more often classified as ER-positive with IHC than with CYT. For PR, however, we found an increased correlation between methods in more recent time periods. This may possibly be explained by more reliable PRIHC results in newer samples, although other explanations may also contribute. Our results indicate stable ER expression in FFPE tissue archived for up to 40 years.

Cost-Effectiveness of Second-Line Endocrine Therapies in Postmenopausal Women with Hormone Receptor-positive and Human Epidermal Growth Factor Receptor 2-negative Metastatic Breast Cancer in Japan.

BACKGROUND: Exemestane (EXE), exemestane + everolimus (EXE + EVE), toremifene (TOR), and fulvestrant (FUL) are second-line endocrine therapies for postmenopausal hormone receptor-positive (HR +)/human epidermal growth factor receptor 2-negative (HER2 -) metastatic breast cancer (mBC) in Japan. Although the efficacy of these therapies has been shown in recent studies, cost-effectiveness has not yet been determined in Japan. OBJECTIVE: This study aimed to examine the cost-effectiveness of second-line endocrine therapies for the treatment of postmenopausal women with HR + and HER2 - mBC. METHODS: A Markov model was developed to analyze the cost-effectiveness of the therapies over a 15-year time horizon from a public healthcare payer's perspective. The efficacy and utility parameters were determined via a systematic search of the literature. Direct medical care costs were used. A discount rate of 2% was applied for costs and outcomes. Subgroup analysis was performed for non-visceral metastasis. A series of sensitivity analyses, including probabilistic sensitivity analysis (PSA) and threshold analysis were performed. RESULTS: Base-case analyses estimated incremental cost-effectiveness ratios (ICERs) of 3 million and 6 million Japanese yen (JPY)/quality-adjusted life year (QALY) gained for TOR and FUL 500 mg relative to EXE, respectively. FUL 250 mg and EXE + EVE were dominated. The overall survival (OS) highly influenced the ICER. With a willingness-to-pay (WTP) threshold of 5 million JPY/QALY, the probability of TOR being cost-effective was the highest. Subgroup analysis in non-visceral metastasis revealed 0.4 and 10% reduction in ICER from the base-case results of FUL5 500 mg versus EXE and TOR versus EXE, respectively, while threshold analysis indicated EVE and FUL prices should be reduced 73 and 30%, respectively. CONCLUSION: As a second-line therapy for postmenopausal women with HR +/HER2 - mBC, TOR may be cost-effective relative to other alternatives and seems to be the most favorable choice, based on a WTP threshold of 5 million JPY/QALY. FUL 250 mg is expected to be as costly and effective as EXE. The cost-effectiveness of EXE + EVE and FUL 500 mg could be improved by a large price reduction. However, the results are highly sensitive to the hazard ratio of OS. Policy makers should carefully interpret and utilize these findings.

Expression of breast cancer type 1 and its relation with expression of estrogen receptors, progesterone receptors, and human epidermal growth factor receptor 2/neu in breast carcinoma on trucut biopsy specimens.

OBJECTIVE: (1) The objective is to study the immunohistochemical expression of Breast cancer type 1 (BRCA1) in breast carcinoma on trucut biopsy specimens and (2) To relate its expression with that of estrogen receptors (ER), progesterone receptors (PR), and human epidermal growth factor receptor 2 (HER-2)/neu and the clinicopathological parameters. SETTINGS AND DESIGN: A cross-sectional hospital-based study was performed in Lady Hardinge Medical College and Shrimati Sucheta Kriplani Hospital, New Delhi, with collaboration of the Departments of Pathology and Surgery from the period of November 2008 to March 2010. MATERIALS AND METHODS: The study group included 54 cytologically proven cases of breast carcinoma. The immunohistochemical expression of BRCA1 was studied and related with expression of ER, PR, and HER-2/neu on their trucut biopsies. RESULTS: The altered expression of BRCA1 (i.e., reduced or absent expression) was seen in 44.4% cases of breast carcinoma while 55.6% had positive expression. About 83% of breast carcinomas with altered BRCA1 expression were larger than 3 cm in size. The breast carcinomas showing altered expression were found to be mostly high grade (63.6%). This was statistically significant. The ER and PR negativity were seen in 62.5% and 79.2% breast carcinomas with altered BRCA1 expression, respectively. The score 3 positivity of HER-2/neu was more common among carcinomas with altered BRCA1 expression (21% vs. 16.7%). The triple negativity was found in 41.7% breast carcinomas having altered BRCA1 expression. This was statistically significant. CONCLUSION: The combination of immunohistochemical expression of BRCA1, ER, PR, and HER-2/neu and clinicopathological details may be helpful in predicting the individuals more likely to carry BRCA1 mutations and thus selecting the candidate and family members for genetic screening for BRCA1 mutations.

Progesterone Decreases in vitro Indoleamine 2, 3-dioxygenase Expression in Dendritic and CD4+ Cells from Maternal-Fetal Interface of Rats.

PROBLEM: Several mechanisms contribute to the tolerogenic state observed during pregnancy, such as the activity of the enzyme indoleamine 2, 3-dioxygenase (IDO). This initializes the catabolism of tryptophan, inducing T cells to apoptosis due to its deprivation and by the action of its catabolites in the placental microenvironment. Progesterone plays an important part on immunological tolerance mechanisms during pregnancy; however, there is no evidence it is related to IDO activity. Thus, this study aimed to investigate progesterone influence on the maternal-fetal interface of pregnant Wistar rats, by identifying IDO positive cells by immunophenotyping and flow cytometry under exogenous progesterone supplementation. METHOD OF STUDY: Placenta and embryo cells were cultured and separated into groups that received interferon γ or progesterone, supplemented or not with mifepristone. After 2 and 24 h, these were labeled with an anti-IDO and a series of antibodies specific to leucocytes and progesterone receptor and processed through flow cytometry analysis. RESULTS: Progesterone induced a significant decrease in the expression of IDO in dendritic cells and CD4+ lymphocytes. CONCLUSION: The blocking of progesterone receptor on these cells by mifepristone restored IDO expression levels and may constitute evidence of the participation of this hormone through a direct route in these cells.

Immunohistochemical Performance of Estrogen and Progesterone Receptor Antibodies on the Dako Omnis Staining Platform: Evaluation in Multicenter Studies.

The analysis of estrogen receptor (ER) and progesterone receptor (PR) expression levels by immunohistochemistry is an important part of the initial evaluation of breast cancer and critically important in treatment planning. Anti-ERα (clone EP1) and anti-PR (clone PgR 1294) antibodies are in development for the Dako Omnis automated staining platform. These antibodies are not yet commercially available and are in performance evaluation, including the 4 international, multicenter studies reported here. For each antibody, a reproducibility study and a method comparison study was done in a randomized manner in order to test the antibodies under conditions closest to real-world user conditions. The reproducibility studies included 5 staining runs on the Dako Omnis with 20 formalin-fixed and paraffin-embedded human breast carcinoma specimens in 3 independent laboratories, and the method comparison studies included several hundred specimens stained on the Dako Omnis and on the Autostainer Link 48 platforms. Stained slides were evaluated for nuclear ER or PR expression according to American Society of Clinical Oncology/College of American Pathologists guidelines (≥1% cut-off for positive) by pathologists who were blinded from the staining method and specimen ID. For both anti-ERα (clone EP1) and anti-PR (clone PgR 1294) on the Dako Omnis, high reproducibility agreement rates were obtained on the interrun, interlaboratory, and interobserver endpoints. High concordance rates were observed between the specimens stained on the Dako Omnis platform and the Autostainer Link 48 platform. Staining quality was excellent for both anti-ERα (clone EP1) and anti-PR (clone PgR 1294) on the Dako Omnis. These results suggest that these antibodies are reliable and reproducible tools for immunohistochemistry analysis of ER and PR expression levels in formalin-fixed and paraffin-embedded breast carcinoma tissues on the Dako Omnis platform.

Progesterone from maternal circulation binds to progestin receptors in fetal brain.

Steroid hormones activate nuclear receptors which, as transcription factors, can regulate critical aspects of neural development. Many regions of the rat forebrain, midbrain and hindbrain express progestin receptors (PR) during perinatal life, suggesting that progesterone may play an important role in the development of the brain. An immunohistochemical approach using two antibodies with differential recognition of ligand-bound PR was used to examine whether fetuses are exposed to maternal progesterone during pregnancy and whether progesterone from maternal circulation can bind to PR within the fetal brain. Findings demonstrate that maternal and fetal serum progesterone levels are positively correlated at the end of gestation, suggesting a common source of progesterone in mothers and fetuses (e.g., the maternal ovary). Additional findings suggest that administration of exogenous progesterone to mothers not only increases fetal serum progesterone levels within 2 h, but appears to increase ligand-bound PR in fetal brain. These findings suggest that progesterone of maternal origin may play a previously overlooked role in neural development. In addition, there are implications for the ongoing prophylactic use of synthetic progestins in pregnant women for the prevention of premature birth. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 767-774, 2017.

Activity of Zearalenone in the Porcine Intestinal Tract.

This study demonstrates that low doses (somewhat above the No Observed Adverse Effect Level, NOAEL) of the mycoestrogen zearalenone (ZEN) and its metabolites display multispecificity towards various biological targets in gilts. The observed responses in gilts were surprising. The presence of ZEN and zearalenols (ZELs) did not evoke a response in the porcine gastrointestinal tract, which was attributed to dietary tolerance. Lymphocyte proliferation was intensified in jejunal mesenteric lymph nodes, and lymphocyte counts increased in the jejunal epithelium with time of exposure. In the distal digestive tract, fecal bacterial counts decreased, the activity of fecal bacterial enzymes and lactic acid bacteria increased, and cecal water was characterized by higher genotoxicity. The accompanying hyperestrogenism led to changes in mRNA activity of selected enzymes (cytochrome P450, hydroxysteroid dehydrogenases, nitric oxide synthases) and receptors (estrogen and progesterone receptors), and it stimulated post-translational modifications which play an important role in non-genomic mechanisms of signal transmission. Hyperestrogenism influences the regulation of the host's steroid hormones (estron, estradiol and progesteron), it affects the virulence of bacterial genes encoding bacterial hydroxysteroid dehydrogenases (HSDs), and it participates in detoxification processes by slowing down intestinal activity, provoking energy deficits and promoting antiporter activity at the level of enterocytes. In most cases, hyperestrogenism fulfils all of the above roles. The results of this study indicate that low doses of ZEN alleviate inflammatory processes in the digestive system, in particular in the proximal and distal intestinal tract, and increase body weight gains in gilts.

Can membrane progesterone receptor α on T regulatory cells explain the ensuing human labour?

Progesterone acts as an immunosteroid by contributing to the establishment of a pregnancy-protective milieu. It seems that it is the responsibility of progesterone to evade the inflammatory events that lead to parturition. T regulatory lymphocytes (Treg cells) could further explain the inhibition of the inflammatory mechanisms that lead to labour through the rapid action of progesterone on this cell subset. We investigated Treg cells and the membrane progesterone receptor α (mPRα) in these immune cells with in relationship to human parturition. This pilot cohort study was conducted in a single-centre tertiary obstetrical unit with 20 normal pregnant women. Variation in the absolute and relative frequency of CD4(+) T cells, Treg cells, and of mPR(α+) Treg cells was calculated by flow cytometry on three occasions (second and third trimesters; delivery day). Our results show that during normal pregnancy there is a generalised increase in Treg cells and mPR(α+) Treg cells, from the second to the third trimesters (23.4% vs. 52.3% and 4.3% vs. 8.3%, respectively). On the contrary, on delivery day, compared with the values in the third trimester, there is a sudden decrease in both Treg cells (52.3% vs. 17.4%) and mPR(α+) Treg cells (8.3% vs. 6.1%). Our findings suggest that human labour may develop as a consequence of a decline in mPR(α+) Treg cells, which reduces progesterone anti-inflammatory action through Treg cells.