Prognostic value of progesterone receptor expression in ovarian cancer: a meta-analysis

Ecological and evolutionary dynamics to design and improve ovarian cancer treatment

Ovarian cancer ecosystems are exceedingly complex, consisting of a high heterogeneity of cancer cells. Development of drugs such as poly ADP-ribose polymerase (PARP) inhibitors, targeted therapies and immunotherapies offer more options for sequential or combined treatments. Nevertheless, mortality in metastatic ovarian cancer patients remains high because cancer cells consistently develop resistance to single and combination therapies, urging a need for treatment designs that target the evolvability of cancer cells. The evolutionary dynamics that lead to resistance emerge from the complex tumour microenvironment, the heterogeneous populations, and the individual cancer cell's plasticity. We propose that successful management of ovarian cancer requires consideration of the ecological and evolutionary dynamics of the disease. Here, we review current options and challenges in ovarian cancer treatment and discuss principles of tumour evolution. We conclude by proposing evolutionarily designed strategies for ovarian cancer, with the goal of integrating such principles with longitudinal, quantitative data to improve the treatment design and management of drug resistance. KEY POINTS/HIGHLIGHTS: Tumours are ecosystems in which cancer and non-cancer cells interact and evolve in complex and dynamic ways. Conventional therapies for ovarian cancer inevitably lead to the development of resistance because they fail to consider tumours' heterogeneity and cellular plasticity. Eco-evolutionarily designed therapies should consider cancer cell plasticity and patient-specific characteristics to improve clinical outcome and prevent relapse.

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.

P53 and TLR4 expression are prognostic markers informing progression free survival of advanced stage high grade serous ovarian cancer

OBJECTIVE

New prognostic biomarkers, and bio-signatures, are urgently needed to facilitate a precision medicine-based approach to more effectively treat patients with high-grade serous ovarian cancer (HGSC). In this study, we analysed the expression patterns of a series of candidate protein biomarkers.

METHODS

The panel of markers which included MyD88, TLR4, MAD2, PR, OR, WT1, p53, p16, CD10 and Ki67 was assessed using immunohistochemistry in a tissue microarray (TMA) cohort of n = 80 patients, composed of stage 3-4 HGSCs. Each marker was analysed for their potential to predict both overall survival (OS) and progression-free survival (PFS).

RESULTS

TLR4 and p53 were found to be individually predictive of poorer PFS (Log Rank, p = 0.017, p = 0.030 respectively). Cox regression analysis also identified high p53 and TLR4 expression as prognostic factors for reduced PFS (p53; HR=1.785, CI=1.036-3.074, p = 0.037 and TLR4; HR=2.175, CI=1.112-4.253, p = 0.023). Multivariate forward conditional Cox regression analysis, examining all markers, identified a combined signature composed of p53 and TLR4 as prognostic for reduced PFS (p = 0.023).

CONCLUSION

Combined p53 and TLR4 marker assessment may help to aid treatment stratification for patients diagnosed with advanced-stage HGSC.

Hormone Receptors and Epithelial Ovarian Cancer: Recent Advances in Biology and Treatment Options

Epithelial ovarian cancer (EOC) is a significant cause of cancer-related mortality in women. Despite advances in diagnosis and treatment, EOC remains a challenging disease to manage, and the 5-year survival rate is still poor. The role of hormone receptors (HRs) in EOC carcinogenesis and prognosis has been actively explored; however, the role of hormone therapy (HT) in the treatment of these tumors is not well established. Most available data on HT mainly come from retrospective series and small early clinical trials. Several of these studies suggest that HT may have a role in adjuvant, maintenance therapy, or in the case of recurrent disease, especially for some subtypes of EOC (e.g., low-grade serous EOC). Furthermore, HT has recently been combined with targeted therapies, but most studies evaluating these combinations are still ongoing. The main aim of this review is to provide an overview of the progress made in the last decade to characterize the biological and prognostic role of HRs for EOC and the developments in their therapeutic targeting through HT.

Chemerin and Chemokine-like Receptor 1 Expression in Ovarian Cancer Associates with Proteins Involved in Estrogen Signaling

Chemerin, a pleiotropic adipokine coded by the RARRES2 gene, has been reported to affect the pathophysiology of various cancer entities. To further approach the role of this adipokine in ovarian cancer (OC), intratumoral protein levels of chemerin and its receptor chemokine-like receptor 1 (CMKLR1) were examined by immunohistochemistry analyzing tissue microarrays with tumor samples from 208 OC patients. Since chemerin has been reported to affect the female reproductive system, associations with proteins involved in steroid hormone signaling were analyzed. Additionally, correlations with ovarian cancer markers, cancer-related proteins, and survival of OC patients were examined. A positive correlation of chemerin and CMKLR1 protein levels in OC (Spearman's rho = 0.6, p < 0.0001) was observed. Chemerin staining intensity was strongly associated with the expression of progesterone receptor (PR) (Spearman´s rho = 0.79, p < 0.0001). Both chemerin and CMKLR1 proteins positively correlated with estrogen receptor β (ERβ) and estrogen-related receptors. Neither chemerin nor the CMKLR1 protein level was associated with the survival of OC patients. At the mRNA level, in silico analysis revealed low RARRES2 and high CMKLR1 expression associated with longer overall survival. The results of our correlation analyses suggested the previously reported interaction of chemerin and estrogen signaling to be present in OC tissue. Further studies are needed to elucidate to which extent this interaction might affect OC development and progression.

Expression of Progesterone Receptor A as an Independent Negative Prognosticator for Cervical Cancer

The role of progesterone receptor A (PRA) for the survival outcome of cervical cancer patients is ambiguous. In mouse models, it has been shown that PRA plays a rather protective role in cancer development. The aim of this study was to assess its expression by immunohistochemistry in 250 cervical cancer tissue samples and to correlate the results with clinicopathological parameters including patient survival. PRA expression was positively correlated with the International Federation of Gynecology and Obstetrics (FIGO) classification scores. PRA was significantly overexpressed in adenocarcinomas compared to squamous epithelial carcinoma subtypes. Correlation analyses revealed a trend association with the HPV virus protein E6, a negative correlation with p16 and a positive correlation with EP3. PRA expression was also associated with the expression of RIP140, a transcriptional coregulator that we previously identified as a negative prognostic factor for survival in cervical cancer patients. Univariate survival analyses revealed PRA as a negative prognosticator for survival in patients with cervical adenocarcinoma. Multivariate analyses showed that simultaneous expression of RIP140 and PRA was associated with the worst survival, whereas with negative RIP140, PRA expression alone was associated with the best survival. We can therefore assume that the effect of nuclear PRA on overall survival is dependent upon nuclear RIP140 expression.

Molecular Management of High-Grade Serous Ovarian Carcinoma

High-grade serous ovarian carcinoma (HGSOC) represents the most common form of epithelial ovarian carcinoma. The absence of specific symptoms leads to late-stage diagnosis, making HGSOC one of the gynecological cancers with the worst prognosis. The cellular origin of HGSOC and the role of reproductive hormones, genetic traits (such as alterations in P53 and DNA-repair mechanisms), chromosomal instability, or dysregulation of crucial signaling pathways have been considered when evaluating prognosis and response to therapy in HGSOC patients. However, the detection of HGSOC is still based on traditional methods such as carbohydrate antigen 125 (CA125) detection and ultrasound, and the combined use of these methods has yet to support significant reductions in overall mortality rates. The current paradigm for HGSOC management has moved towards early diagnosis via the non-invasive detection of molecular markers through liquid biopsies. This review presents an integrated view of the relevant cellular and molecular aspects involved in the etiopathogenesis of HGSOC and brings together studies that consider new horizons for the possible early detection of this gynecological cancer.

Genetic variation in progesterone receptor gene and ovarian cancer risk: A case control study

BACKGROUND

Previous studies examined the association of genetic variation in progesterone receptor (PR) gene (PGR) with ovarian cancer, possibly by altering the expression of PR-B isoform, but with mixed outcome.

OBJECTIVE

This study evaluated the association of PGR variants with ovarian cancer and associated features.

METHODS

This was a retrospective case-control study, which involved 82 women with ovarian cancer and 95 cancer-free women who served as controls. Genotyping was done by Taqman® SNP genotyping by qRT-PCR. The PGR variants tested were rs471767 (A > G), rs590688 (G > C), and rs10895068 (G > A). Stratification analyses were used for testing the correlation between the PGR variants with ovarian cancer susceptibility according to menstruation status, FIGO classification, pathological grade, and chemotherapy.

RESULTS

Significantly lower minor allele frequency (MAF) of rs10895068 was seen among ovarian cancer patients, thereby imparting disease protective nature to this variant. Significant association of rs10895068 genotypes with ovarian cancer was seen under the dominant model, but not other genetic models. FIGO classification correlated positively with rs471767 and rs10895068, while rs10895068 correlated positively with lymph node positivity. Three-locus haplotype analysis identified ACA and HCG haplotypes to be negatively associated with the risk of ovarian cancer.

CONCLUSIONS

This report confirms the contribution of PGR variants, specifically the rs10895068 (+331G/A) the etiology of ovarian cancer.

Role of NRF2 in Ovarian Cancer

Among gynaecologic malignancies, ovarian cancer is one of the most dangerous, with a high fatality rate and relapse due to the occurrence of chemoresistance. Many researchers demonstrated that oxidative stress is involved in tumour occurrence, growth and development. Nuclear factor erythroid 2-related factor 2 (NRF2) is an important transcription factor, playing an important role in protecting against oxidative damage. Increased levels of Reactive Oxygen Species (ROS) activate NRF2 signalling, inducing the expression of antioxidant enzymes, such as haem oxygenase (HO-1), catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD), that protect cells against oxidative stress. However, NRF2 activation in cancer cells is responsible for the development of chemoresistance, inactivating drug-mediated oxidative stress that normally leads to cancer cells’ death. In this review, we report evidence from the literature describing the effect of NRF2 on ovarian cancer, with a focus on its function in drug resistance, NRF2 natural and synthetic modulators and its protective function in normal ovarian preservation.

AKR1C1/2 inhibition by MPA sensitizes platinum resistant ovarian cancer towards carboplatin

In recurrent epithelial ovarian cancer (EOC) most patients develop platinum-resistance. On molecular level the NRF2 pathway, a cellular defense mechanism against reactive oxygen species, is induced. In this study, we investigate AKR1C1/2, target of NRF2, in a well-established EOC collective by immunohistochemistry and in a panel of ovarian cancer cell lines including platinum-resistant clones. The therapeutic effect of carboplatin and MPA as monotherapy or in combination was assessed by functional assays, using OV90 and OV90cp cells. Molecular mechanisms of action of MPA were investigated by NRF2 silencing and AKR activity measurements. Immunohistochemical analysis revealed that AKR1C1/2 is a key player in the development of chemoresistance and an independent indicator for short PFS (23.5 vs. 49.6 months, p = 0.013). Inhibition of AKR1C1/2 by MPA led to a concentration- and time-dependent decline of OV90 viability and to an increased response to CP in vitro. By NRF2 silencing, however, the effects of MPA treatment were reduced. Concludingly, our data suggest that a combination therapy of carboplatin and MPA might be a promising therapeutic approach to increase response rates of EOC patients, which should be explored in clinical context.

The Flavonoid Baicalein Negatively Regulates Progesterone Target Genes in the Uterus in Vivo

Baicalein is a flavonoid extracted from the root of Scutellaria baicalensis (Chinese skullcap) and is consumed as part of this botanical dietary supplement to reduce oxidative stress, pain, and inflammation. We previously reported that baicalein can also modify receptor signaling through the progesterone receptor (PR) and glucocorticoid receptor (GR) in vitro, which is interesting due to the well-established roles of both PR and GR in reducing inflammation. To understand the effects of baicalein on PR and GR signaling in vivo in the uterus, ovariectomized CD-1 mice were treated with DMSO, progesterone (P4), baicalein, P4 with baicalein, and P4 with RU486, a PR antagonist, for a week. The uteri were collected for histology and RNA sequencing. Our results showed that baicalein attenuated the antiproliferative effect of P4 on luminal epithelium as well as on the PR target genes HAND2 and ZBTB16. Baicalein did not change levels of PR or GR RNA or protein in the uterus. RNA sequencing data indicated that many transcripts significantly altered by baicalein were regulated in the opposite direction by P4. Similarly, a large portion of GO/KEGG terms and GSEA gene sets were altered in the opposite direction by baicalein as compared to P4 treatment. Treatment of baicalein did not change body weight, organ weight, or blood glucose level. In summary, baicalein functioned as a PR antagonist in vivo and therefore may oppose P4 action under certain conditions such as uterine hyperplasia, fibroids, and uterine cancers.

Development and Validation of a Nomogram to Predict the Probability of Venous Thromboembolism in Patients with Epithelial Ovarian Cancer

To identify predictive factors and develop a nomogram to predict the probability of venous thromboembolism for epithelial ovarian cancer patients. Methods: Our study cohort was composed of 208 EOC patients who had received initial treatment in Sun Yat-sen Memorial Hospital from January 2016 to March 2020. Clinicopathological variables predictive of VTE were identified using univariate logistic analysis. A multivariate logistic regression model was used to select the predictive factors used for nomogram. The accuracy of nomogram was evaluated by the Concordance index (C-index), the area under the receiver–operator characteristic (ROC) curve, area under concentration-time curve (AUC) and the calibration curve. Results: Advancing age (hazard ratio [HR], 1.042; 95% confidence interval [CI], 1.000-1.085; P = .048), higher D-dimer level (HR, 1.144; 95%CI, 1.020-1.283; P = .022), lower PR immunohistochemical positive rate (HR, 0.186; 95%CI, 0.034-1.065; P = .059) and higher Ki67 immunohistochemical positive rate (HR, 4.502; 95%CI, 1.637-12.380; P = .004) were found to be independent risk factors for VTE, and were used to construct the nomogram. The C-index for VTE prediction of the nomogram was 0.75. Conclusions: We constructed and validated a nomogram able to quantify the risk of VTE for EOC patients, which can be applied in recognizing EOC patients with high risk of VTE.

Highly Expressed Progesterone Receptor B Isoform Increases Platinum Sensitivity and Survival of Ovarian High-Grade Serous Carcinoma

Simple Summary

Ovarian high-grade serous carcinoma is the deadliest ovarian cancer. Cancer cells develop resistance to anti-cancer regimens leading to poor prognosis. Previous studies showed that the progesterone receptor was associated with better rates of survival of ovarian cancer patients. We aimed to investigate the association between the progesterone receptor and its isoform-B and platinum sensitivity of ovarian high-grade serous carcinoma. We found that strong progesterone receptor-B expression was associated with better platinum sensitivity and better survival in high-grade serous ovarian cancer patients. Our clinical data also showed that a high expression of progesterone receptor-B and optimal debulking were the independent factors associated with better platinum sensitivity. In a cell model, enhancing progesterone receptor-B expression and progesterone treatment increased platinum sensitivity and platinum-related apoptosis of the ovarian cancer cells. These might be potential therapeutic targets of ovarian high-grade serous carcinoma.

Abstract

Background: Expression of the progesterone receptor (PR) has been reported to influence survival outcomes in patients with ovarian high-grade serous carcinoma (HGSC). In the present study, we attempted to investigate the association among PR and its isoforms’ expression, platinum sensitivity, and survival in ovarian HGSC. Material and methods: This retrospective study reviewed ovarian HGSC patients who received surgery followed by adjuvant chemotherapy. We analyzed total PR and PR isoform-B (PR-B) expression by immunohistochemical staining and quantified using the H-score. Then, we compared platinum sensitivity and survival outcomes between those patients with weak and strong PR-B expression. Cisplatin viability assays were carried out in ovarian HGSC cell lines (OC-3-VGH and OVCAR-3) with different PR-B expression. Results: Among 90 patients, 49 and 41 patients were considered to have platinum-sensitive and platinum-resistant disease, respectively. Pearson’s correlation model showed that the H-score of total PR correlated positively with PR-B (r = 0.813). The PR-B H-score of tumors was significantly higher in the platinum-sensitive group (p = 0.004). Multivariate analysis revealed that the PR-B H-score and optimal debulking status were independent factors predicting platinum sensitivity. When compared with strong PR-B expression, patients with weak PR-B had significantly poorer progression-free (p = 0.021) and cancer-specific survival (p = 0.046). In a cell model, cisplatin-resistant OC-3-VGH cells expressed a lower level of PR-B than wild-type cells. Overexpression of PR-B or progesterone could increase cisplatin sensitivity in both OC-3-VGH and OVCAR-3 cells via the mechanism of promoting cisplatin-related apoptosis. Conclusions: When compared to weak PR-B, ovarian HGSC patients with a strong PR-B expression had a better chance of platinum sensitivity and survival, and this finding was compatible with our experimental results. Progesterone seemed to be a platinum sensitizer, but the value of adding progesterone in the treatment of ovarian HGSC should be further investigated.

Expression of hormone receptors predicts survival and platinum sensitivity of high-grade serous ovarian cancer

High-grade serous ovarian cancer (HGSOC) has abundant expression of hormone receptors, including androgen receptor (AR), estrogen receptor α (ER), and progesterone receptor (PR). The effects of hormone receptors on prognosis of HGSOC were first evaluated in online databases. Their prognostic values were then explored and validated in our inhouse TJ-cohort (92 HGSOC patients) and in a validation cohort (33 HGSOC patients), wherein hormone receptors were detected immunohistochemically. High expression of hormone receptors denoted longer progression-free survival (PFS), overall survival (OS), and platinum-free interval (PFI). Platinum-sensitive patients had higher expression of hormone receptors than their counterparts. Correlation analysis revealed significant positive correlations between hormone receptors expression and survival. AR, ER, and PR had predictive and prognostic values, alone and in combination. By receiver operating characteristic curve (ROC) analysis, co-expression of AR, ER, and PR had an improved predictive performance with an area under the curve (AUC) value of 0.945. Expression of hormone receptors predicts survival and platinum sensitivity of HGSOC. AR, ER, and PR might be feasible prognostic biomarkers for HGSOC by immunohistochemical analysis.

LINC-PINT suppresses tumour cell proliferation, migration and invasion through targeting miR-374a-5p in ovarian cancer

LncRNA LINC-PINT acts as an important regulator in the development of many cancers. The current study aimed to explore the role of LINC-PINT in the progression of ovarian cancer (OC). LINC-PINT expression level in different FIGO stages of OC and its adjacent tissues, normal HOSE and OC cell lines (A2780, SKOV3, OVCAR3 and HO-8910) was determined by qRT-PCR. Survival analysis on LINC-PINT and OC patients was conducted by Kaplan-Meier. CCK-8, flow cytometry, wound-healing, Transwell assays and western blot were performed to detect the effects of LINC-PINT on proliferation, apoptosis, migration, invasion and EMT process in OC cells. Target gene of LINC-PINT was predicted by Starbase and verified by dual-luciferase reporter assay. The expression of miR-374a-5p in normal and OC tissues, LINC-PINT- or siLINC-PINT-modified OC cells was determined. Moreover, rescue assay was carried out to confirm whether LINC-PINT contributes to the development of OC cells through targeting miR-374a-5p. Low expression of LINC-PINT was observed in OC tissues and cells, noticeably, LINC-PINT expression was even lower in OC tissues with higher FIGO stage. Increased LINC-PINT expression significantly inhibited cell proliferation, promoted apoptosis and suppressed migration, invasion and EMT process, while silencing of LINC-PINT caused the opposite results. Moreover, LINC-PINT sponged miR-374a-5p and overexpressed miR-374a-5p attenuated the effect of up-regulated LINC-PINT on cell viability, migration, invasion and apoptosis. LINC-PINT acts as a tumour suppressor, as it could inhibit cell proliferation, migration, invasion and EMT process, and promote cell apoptosis through down-regulating miR-374a-5p. SIGNIFICANCE OF THE STUDY: Ovarian cancer (OC), which is a frequently diagnosed tumour in female reproductive organs, has a high incidence rate behind cervical cancer and endometrial cancer. LncRNA LINC-PINT acts as an important regulator in the development of many cancers. The current study aimed to explore the role of LINC-PINT in the progression of ovarian cancer (OC) and found that LINC-PINT inhibited cell proliferation, migration invasion and EMT process of OC cell via regulating miR-374a-5p; it might be a potential target for OC treatment.

Fallopian tube initiation of high grade serous ovarian cancer and ovarian metastasis: Mechanisms and therapeutic implications

Ovarian cancer is the most lethal gynecologic malignancy and the fifth leading cause of cancer-related death in women. Although outcomes have improved in recent years, there remains an unmet clinical need to understand the early pathogenesis of ovarian cancer in order to identify new diagnostic approaches and agents of chemoprevention and chemotherapy. While high grade serous ovarian cancer (HGSOC), the most abundant histotype, was initially thought to arise from the ovarian surface epithelium, there is an increasing body of evidence suggesting that HGSOC originates in the fallopian tube. With this new understanding of cell of origin, understanding of disease development requires analysis with a novel perspective. Currently, factors that drive the initiation and migration of dysplastic tubal epithelial cells from the fallopian tube to the ovary are not yet fully defined. These factors include common mutations to fallopian tube epithelial cells, as well as factors originating from both the fallopian tube and ovary which are capable of inducing transformation and dissemination in said cells. Here, we review these changes, their causative agents, and various potential means of intervention.

Hormone replacement therapy after surgery for epithelial ovarian cancer

BACKGROUND

Women who have undergone surgical treatment for epithelial ovarian cancer (EOC) may develop menopausal symptoms due to immediate loss of ovarian function following surgery and chemotherapy. Women may experience vasomotor symptoms, sleep disturbance, difficulty concentrating, sexual dysfunction, vaginal symptoms and accelerated osteoporosis. Although hormone replacement therapy (HRT) is the most effective treatment to relieve these symptoms, its safety has been questioned for women with EOC.

OBJECTIVES

To assess the safety and efficacy of HRT for menopausal symptoms in women surgically treated for EOC.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 6), MEDLINE via Ovid (1946 to 12 June 2019) and Embase via Ovid (1980 to 2019, week 23). We also handsearched conference reports and trial registries. There was no language restriction.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) with participants of any age and menopausal status who had undergone surgery for EOC and, after diagnosis and treatment, used any regimen and duration of HRT compared with placebo or no hormone therapy. We also included trials comparing different regimens or duration of administration of HRT.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified studies that met the inclusion criteria. They used Covidence to extract study characteristics, outcome data and to assess methodological quality of the included studies.

MAIN RESULTS

Our search strategy identified 2617 titles, of which 2614 titles were excluded. Three studies, involving 350 women, met our inclusion criteria. Two of the studies included pre and postmenopausal women, and the third only included premenopausal women. The overall age range of those women included in the studies was 20 to 89.6 years old, with a median follow-up ranging from 31.4 months to 19.1 years. The geographical distribution of participants included Europe, South Africa and China. All stages and histological subtypes were included in two of the studies, but stage IV disease had been excluded in the third. The three included studies used a variety of HRT regimens (conjugated oestrogen with or without medroxyprogesterone and with or without nylestriol) and HRT administrations (oral, patch and implant), In all studies, the comparisons were made versus women who had not received HRT. The studies were at low or unclear risk of selection and reporting bias, and at high risk of performance, detection and attrition bias. The certainty of the evidence was low for overall survival and progression-free survival, and very low for quality-of-life assessment, incidence of breast cancer, transient ischaemic attack (TIA), cerebrovascular accident (CVA) and myocardial infarction (MI). Meta-analysis of these studies showed that HRT may improve overall survival (hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.54 to 0.93; 350 participants, 3 studies; low-certainty evidence). Quality-of-life assessment by use of the EORTC-C30 questionnaire was performed only in one study. We are uncertain whether HRT improves or reduces quality of life as the certainty of the evidence was assessed as very low (mean difference (MD) 13.67 points higher, 95% CI 9.26 higher to 18.08 higher; 1 study; 75 participants; very low-certainty evidence). Likewise, HRT may make little or no difference to progression-free survival (HR 0.76, 95% CI 0.57 to 1.01; 275 participants, 2 studies; low-certainty evidence). We are uncertain whether HRT improves or reduces the incidence of breast cancer (risk ratio (RR) 2.00, 95% CI 0.19 to 21.59; 225 participants, 2 studies; very low-certainty evidence); TIA (RR 5.00, 95% CI 0.24 to 102.42; 150 participants, 1 study; very low-certainty evidence); CVA (RR 0.67, 95% CI 0.11 to 3.88; 150 participants, 1 study; very low-certainty evidence); and MI (RR 0.20, 95% CI 0.01 to 4.10; 150 participants, 1 study; very low-certainty evidence). The incidence of gallstones was not reported in the included studies.

AUTHORS' CONCLUSIONS

Hormone replacement therapy may slightly improve overall survival in women who have undergone surgical treatment for EOC, but the certainty of the evidence is low. HRT may make little or no difference to quality of life, incidence of breast cancer, TIA, CVA and MI as the certainty of the evidence has been assessed as very low. There may be little or no effect of HRT use on progression-free survival. The evidence in this review is limited by imprecision and incompleteness of reported relevant outcomes and therefore the results should be interpreted with caution. Future well-designed RCTs are required as this is an important area to women experiencing menopausal symptoms following surgical treatment for ovarian cancer, especially as doctors are often reluctant to prescribe HRT in this scenario. The evidence in this review is too limited to support or refute that HRT is very harmful in this population.

Correlation of NRF2 and progesterone receptor and its effects on ovarian cancer biology

Purpose

This study aimed to investigate the potential prognostic impact of nuclear factor erythroid 2-related factor 2 (NRF2) and progesterone receptor A (PRA)/progesterone receptor B (PRB) in ovarian cancer patients which might be the rationale for putative new treatment strategies.

Patients and methods

The presence of NRF2 and PRA/PRB was investigated in 156 ovarian cancer samples using immunohistochemistry (IHC). Staining of NRF2 and PRA/PRB was rated using the semi-quantitative immunoreactive score (IR score, Remmele’s score) and correlated to clinical and pathological data. NRF2 and PRA/PRB expression were compared with respect to the overall survival (OS).

Results

NRF2 staining was different in both, the cytoplasm and nucleus between the histological subtypes (p=0.001 and p=0.02, respectively). There was a significant difference in the PRA expression comparing all histological subtypes (p=0.02). Histological subtypes showed no significant differences in the PRB expression. A strong correlation of cytoplasmic NRF2 and PRA expression was detected (cc=0.247, p=0.003) as well as of cytoplasmic NRF2 and PRB expression (cc=0.25, p=0.003), confirmed by immunofluorescence double staining. Cytoplasmic NRF2 expression was associated with a longer OS (median 50.6 vs 32.5 months; p=0.1) as it was seen for PRA expression (median 63.4 vs 33.1 months; p=0.08), although not statistically significant. In addition, high PRB expression (median 80.4 vs 32.5 months; p=0.04) and concurrent expression of cytoplasmic NRF2 and PRA were associated with a significantly longer OS (median 109.7 vs 30.6 months; p=0.02). The same relationship was also noted for NRF2 and PRB with improved OS for patients expressing both cytoplasmic NRF2 and PRB (median 153.5 vs 30.6 months; p=0.009). Silencing of NFE2L2 induced higher mRNA expression of PGR in the cancer cell line OVCAR3 (p>0.05) confirming genetic interactions of NRF2 and PR.

Conclusion

In this study, the combination of cytoplasmic NRF2 and high PRA/PRB expression was demonstrated to be associated with improved overall survival in ovarian cancer patients. Further understanding of interactions within the NRF2/AKR1C1/PR pathway could open new additional therapeutic approaches.

Cadmium induces progesterone receptor gene expression via activation of estrogen receptor in human ovarian cancer cells

Cadmium (Cd) as a metalloesterogen may have a role in development of ovarian cancer. One of the critical target genes of estrogens is progesterone receptors (PRs). There are controversial studies on association between Cd, PRs, and cell proliferation. This study investigates the effect of Cd on proliferation of ovarian cancer cell lines, PRA and PRB expression and their relationship. OVCAR3 and SKOV3 cells were treated with CdCl₂ (1-100 nM) and cell proliferation was assayed using bromodeoxyuridine (BrdU) method. The mechanism underlying the proliferative effect of Cd mediated by PRs was examined using cell transfection with PR- small interfering RNA (siRNA) and western blot analysis. Our results showed the involvement of PRs in Cd induced proliferation of ovarian cancer cells. Progesterone receptors are involved in proliferative effect of Cd. Moreover, Cd modified the expression of PRA and PRB and induced ovarian cancer cell proliferation through the change of PRA/PRB ratio. In conclusion, there is a mechanistic association between Cd effects on ovarian cancer cell proliferation, estrogen receptors and PRs expression.

Estrogen receptor β is associated with expression of cancer associated genes and survival in ovarian cancer

Background

In ovarian cancer, the role of estrogen receptors (ERs), particularly of ERβ, being suggested as tumor suppressor in breast and prostate cancer, remains unclear. We examined the expression of nuclear and cytoplasmic ERβ in ovarian cancer and correlated it with expression of ovarian cancer markers CA125, CEA and CA72–4, steroid hormone receptors ERα and PR, cancer-associated genes EGFR, p53, HER2 and proliferation marker Ki-67. Additionally we examined to what extent expression of ERβ and the other proteins affects survival of ovarian cancer patients.

Methods

We established a tissue microarray from 171 ovarian cancer patients and performed immunohistochemical analyses of the mentioned proteins.

Results

Nuclear ERβ was detected in 47.31% of the ovarian cancer tissues and cytoplasmic expression of this receptor was observed in 23.08%. Nuclear expression of ERβ was significantly decreased in the G3 subgroup compared to better differentiated cancers (p <  0.01) and correlated with ovarian cancer markers CEA (95% CI 0.1598–0.4465; p <  0.0001) and CA72–4 (95% CI 0.05953–0.3616; p <  0.01). Cytoplasmic ERβ expression correlated with EGFR levels (95% CI 0.1059–0.4049; p <  0.001). ERα expression was associated with expression of CA125 and PR. Overall survival of patients with tumors expressing cytoplasmic ERβ was significant longer compared to those with ERβ-negative ovarian cancer (chi-square statistic of the log-rank, p < 0.05). Progression-free survival was dependent on expression of PR (chi-square statistic of the log-rank, p < 0.05) and Ki-67 (p = 0.05).

Conclusions

Our data suggest an important, but distinct role of nuclear and cytoplasmic ERβ expression in ovarian cancer and encourage further studies on its role in this cancer entity.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4898-0) contains supplementary material, which is available to authorized users.

Irilone from Red Clover ( Trifolium pratense) Potentiates Progesterone Signaling

The use of botanical dietary supplements is becoming increasingly popular for the alleviation of hormonal-based conditions such as hot flashes, premenstrual syndrome, and fertility. Estrogen and progesterone receptors (ER and PR) play an essential role in these processes. However, despite the fact that many therapies used to alleviate gynecological conditions act through PR-mediated mechanisms, few studies have investigated or identified any herbal natural product components that act on this receptor. In the current study, we used a progesterone response element (PRE)-luciferase (Luc) reporter assay to identify four phytoprogestins present in a standardized red clover ( Trifolium pratense) extract. We found that the component irilone (1) potentiated the effect of progesterone in both endometrial and ovarian cancer cell lines. In these cancers, progesterone action is generally associated with positive outcomes; thus the potentiating effect of 1 may provide entirely new strategies for enhancing progesterone signaling as a means of mitigating conditions such as fibroids and endometriosis. Formononetin (3) and biochanin A (4) exhibited mixed agonist activity, while prunetin (2) acted only as an antagonist. Collectively, these results suggest that the effects of red clover extract repeatedly observed in cultured cells and the inverse correlation between risk of various cancers and flavonoid intake may be due, in part, to altered progesterone signaling.

The Flavonoid Apigenin Is a Progesterone Receptor Modulator with In Vivo Activity in the Uterus

Apigenin is a flavonoid with well-documented anti-cancer properties; however, its mechanisms of action are still unclear. We previously identified apigenin as a potential phytoprogestin, a natural product with a chemical scaffold that interacts with the progesterone receptor (PR). Our objective was to characterize the ability of apigenin to interact with PR through molecular docking studies, in vitro activity assays, and the ability of apigenin to elicit progestin-like effects in vivo. Molecular docking confirmed that apigenin could interact with PR, though with lower affinity than progesterone due to fewer van der Waals interactions. In Ishikawa cells stably expressing PR-B, apigenin significantly increased progesterone response element/luciferase (PRE/Luc) activity at 5 and 10 μM, but not in the parental Ishikawa cells that lack PR expression. In the presence of 100 nM of progesterone, 10 μM apigenin reduced PRE/Luc activity, indicative of mixed agonist activity. Apigenin also triggered degradation of PR in Ishikawa PR-B cells as measured by western blot. Apigenin reduced proliferation of Ishikawa cells, but through a PR-independent mechanism. In contrast, apigenin and progesterone both stimulated proliferation of T47D cells, an effect blocked by RU486. Apigenin activated other nuclear receptors evidenced by increased luciferase activity in MDA-MB-231 cells, which are PR negative. In vivo, apigenin blocked the genistein-stimulated increase in uterine epithelial cell height; stimulated endometrial expression of Hand2, a transcription factor stimulated by PR, and significantly reduced genistein-induced proliferation. In summary, apigenin is a phytoprogestin, with mixed agonist activity that demonstrates activity in vivo by hindering estrogen receptor-mediated uterine proliferation.