Prognostic significance of progesterone receptor immunohistochemistry in endometrial carcinoma

Prognostic Value of 16α-18F-Fluoro-17β-Estradiol PET as a Predictor of Disease Outcome in Endometrial Cancer: A Prospective Study

The purpose of this study was to evaluate the potential of 16α-¹⁸F-fluoro-17β-estradiol (¹⁸F-FES) PET to predict prognosis in patients with endometrial cancer (EC). Methods: In total, 67 patients with International Federation of Gynecology and Obstetrics (FIGO) stage I-IV EC underwent ¹⁸F-FES and ¹⁸F-FDG PET/CT before treatment. The SUV_mean of the primary tumor was compared with the clinical characteristics, and the relationships between SUV and progression-free survival (PFS) or overall survival were analyzed. Results: ¹⁸F-FES SUV was significantly associated with stage, histology, lymphovascular space involvement (LVSI), and lymph node metastasis, and ¹⁸F-FDG SUV was significantly associated with stage, myometrial invasion, tumor size, and lymph node metastasis. Receiver-operating characteristic curve analysis revealed that ¹⁸F-FES SUV could significantly detect tumor progression and survival, with areas under the curve of 0.813 and 0.790, respectively, whereas ¹⁸F-FDG SUV could detect them with areas under the curve of 0.557 and 0.635, respectively. The Kaplan-Meier survival curve showed that patients with a low ¹⁸F-FES SUV had significantly poor PFS (P < 0.001) and overall survival (P = 0.001) compared with patients with a high SUV, whereas ¹⁸F-FDG showed no significant differences. In a subanalysis of 27 patients with a low risk of recurrence (FIGO stage IA endometrioid carcinoma [grade 1 or 2] without LVSI), those with a low ¹⁸F-FES SUV also had poorer PFS than those with a high SUV (P = 0.002). In multivariate analysis, an ¹⁸F-FES SUV of less than 2.63 (P = 0.037; hazard ratio, 10.727; 95% CI, 1.16-99.35) and FIGO stages III and IV (P = 0.042; hazard ratio, 8.838; 95% CI, 1.09-71.84) were significantly associated with PFS. Conclusion: A low ¹⁸F-FES for the primary tumor was strongly associated with prognostic factors of EC such as LVSI and lymph node metastasis, and a low ¹⁸F-FES SUV was an independent prognostic factor for PFS in patients with EC. These data suggest that pretreatment ¹⁸F-FES PET might be useful in determining the appropriate treatment for patients with EC.

Hormonal receptor expression in endometrial carcinoma: A retrospective immunohistochemical study in a Nigerian tertiary hospital

Background:

Endometrial carcinoma is the commonest genital tract malignancy in most developed nations, but it lags behind cervical carcinoma and ovarian cancers in most developing nations including Nigeria. Estrogen has been described as a promoter of endometrial carcinogenesis.

Objectives:

The aim of this study was to demonstrate the frequency of estrogen receptor (ER) and progesterone receptor (PR) expressions of endometrial carcinoma and to correlate it with tumour grade.

Materials and Methods:

Cases of endometrial carcinoma diagnosed in the Department of Pathology over a 10-year period were reviewed retrospectively. The paraffin-embedded blocks were retrieved, and immunohistochemistry for ER and PR was performed on them. Haematoxylin and eosin (H&E) slides were reviewed, and tumours were graded by three independent pathologists. Data were analysed using SPSS version 22. The level of significance was set at P ≤ 0.05.

Results:

There were 44 cases of endometrial carcinoma. ER and PR were positive in 29.5% and 18.2% of endometrial carcinoma, respectively. There was no significant association between ER (P = 0.361) and PR (P = 0.204) expressions and histological grade of the tumour. The most common histological grade was grade 3 with 70% of cases (36 cases), whereas 13 cases (26%) were grade 2 and only 2 cases (4%) were grade 1.

Conclusion:

The positive expressions of ER and PR in endometrial carcinoma suggest that steroid receptor studies may be of potential benefit in the management of some patients with endometrial carcinoma. Future studies employing larger sample size are therefore recommended.

Preponderance of endometrial carcinoma in elderly patients

Elderly patients with endometrial carcinoma (EMC) are considered to have a poor clinical outcome. The present study included 79 patients aged ≥70 years with EMC stage I or II according to the International Federation of Gynecology and Obstetrics classification, and it was conducted to analyse the clinicopathological significance of histological type (I or II), depth of myometrial invasion (<1/2 or ≥1/2), lymphovascular invasion (+ or -) and immunohistochemical profile. The aim of these analyses was to determine whether these factors may adversely affect the patient outcome and the underlying mechanisms. The immunohistochemical markers used were estrogen receptor (ER), Ki-67 and p53. The expression of these markers was evaluated as high (+) or low (-). Accordingly, the patients were divided into groups as follows: 54 cases type I vs. 25 cases type II; 48 cases with myometrial invasion <1/2 vs. 31 cases without myometrial invasion ≥1/2; 63 cases with lymphovascular invasion vs. 16 cases without lymphovascular invasion; 57 cases with ER (+) vs. 22 cases with ER (-); 24 cases with Ki-67 (+) vs. 55 cases with Ki-67 (-); and 29 cases with p53 (+) vs. 50 cases with p53 (-). In conclusion, close attention must be paid to elderly patients with EMC due to the tumor's intrinsic aggressiveness, which may include the ER (-) and p53 (+) pattern as an independent poor prognostic factor.

MIG-6 suppresses endometrial epithelial cell proliferation by inhibiting phospho-AKT

Background

Aberrant hyperactivation of epithelial proliferation, AKT signaling, and association with unopposed estrogen (E2) exposure is the most common endometrial cancer dysfunction. In the normal uterus, progesterone (P4) inhibits proliferation by coordinating stromal-epithelial cross-talk, which we previously showed is mediated by the function of Mitogen-inducible gene 6 (Mig-6). Despite their attractive characteristics, non-surgical conservative therapies based on progesterone alone have not been universally successful. One barrier to this success has been the lack of understanding of the P4 effect on endometrial cells.

Method

To further understand the role of Mig-6 and P4 in controlling uterine proliferation, we developed a Sprr2f-cre driven mouse model where Mig-6 is specifically ablated only in the epithelial cells of the uterus (Sprr2f^cre+Mig-6^f/f). We examined P4 effect and regulation of AKT signaling in the endometrium of mutant mice.

Results

Sprr2f^cre+Mig-6^f/f mice developed endometrial hyperplasia. P4 treatment abated the development of endometrial hyperplasia and restored morphological and histological characteristics of the uterus. P4 treatment reduced cell proliferation which was accompanied by decreased AKT signaling and the restoration of stromal PGR and ESR1 expression. Furthermore, our in vitro studies revealed an inhibitory effect of MIG-6 on AKT phosphorylation as well as MIG-6 and AKT protein interactions.

Conclusions

These data suggest that endometrial epithelial cell proliferation is regulated by P4 mediated Mig-6 inhibition of AKT phosphorylation, uncovering new mechanisms of P4 action. This information may help guide more effective non-surgical interventions in the future.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4502-7) contains supplementary material, which is available to authorized users.

Added Value of Estrogen Receptor, Progesterone Receptor, and L1 Cell Adhesion Molecule Expression to Histology-Based Endometrial Carcinoma Recurrence Prediction Models: An ENITEC Collaboration Study

Objectives

Endometrial carcinoma mortality is mainly caused by recurrent disease, and various immunohistochemical markers to predict recurrences have been studied. Loss of the estrogen receptor (ER) and progesterone receptor (PR) and the presence of the L1 cell adhesion molecule (L1CAM) are promising markers, but their combined value has not been studied.

Materials and Methods

Expression of ER, PR, and L1CAM was immunohistochemically determined in 293 endometrial carcinomas from 11 collaborating European Network for Individualized Treatment of Endometrial Cancer centers. Estrogen receptor, PR, or L1CAM staining was considered positive or negative when expressed by greater than or equal to 10% or less than 10% of the tumor cells, respectively. The association between these markers and clinicopathological markers, and their combined value in predicting survival were calculated, both in the entire cohort and in a selected groups of stage I endometrioid and low-risk stage I endometrioid carcinomas.

Results

Estrogen receptor and PR were negative in 19% and 28% of the cases, respectively, and L1CAM was positive in 18%. All 3 were associated with advanced stage, high-grade, nonendometrioid histology, lymphovascular space invasion (LVSI), and reduced disease-free survival. Only advanced stage, loss of PR, and LVSI were associated with reduced disease-free survival in multivariate analysis. A prognostic model including these 3 markers was superior to 1 including only the 3 immunohistochemical markers, which was superior to the traditional model. In both the stage I endometrioid and the low-risk stage I endometrioid groups, only loss of PR was associated with reduced disease-free survival.

Conclusions

Loss of ER and PR, and the presence of L1CAM are associated with high risk characteristics, and loss of PR is the strongest predictor of recurrent disease. Although a combination of these 3 markers is slightly superior to the traditional histological markers, a prognostic model including stage, PR expression, and LVSI is the most promising model in the identification of high risk carcinomas. In the stage I endometrioid carcinomas, PR immunohistochemistry appears to be of additional value in predicting recurrences.

Impact of Hormone Receptor Status and Ki-67 Expression on Disease-Free Survival in Patients Affected by High-risk Endometrial Cancer

Objectives

The aim of this study was to evaluate the immunohistochemical (IHC) expression of Ki-67, estrogen receptors α (ERsα), and progesterone receptors (PRs) in high-risk endometrial cancer patients and to assess their prognostic impact.

Methods/Materials

Immunohistochemical expression of Ki-67, ERsα, and PRs was evaluated in primary untreated endometrial cancer. The correlation among IHC staining and risk factors of recurrence such as age, Federation International of Gynecology and Obstetrics stage, grading, depth of invasion, and metastatic spread was assessed.

Results

Eighty-two patients were available for the analysis. Mean ± SD age was 65.05 ± 10.48 years. The IHC assessment revealed a lack of ERα in 46.3% and of PR in 48.7% as well as a high Ki-67 in 31.7%. Loss of ERα and PR was associated with a significant higher rate of advanced stage of disease, a higher frequency of G3 tumors, and a myometrial invasion greater than 50%. A strong Ki-67 expression correlated with a deeper myometrial invasion. Analysis of the interrelationship between receptor immunonegativity revealed a relevant association of ERα immunolocalization with PR and with a high Ki-67 expression. The present study also showed that loss of ERα (P = 0.003), advanced Federation International of Gynecology and Obstetrics stage (P < 0.001), and high Ki-67 (P = 0.004) were independent prognostic factors of a shorter disease-free survival. Importantly, loss of ERα, loss of PR, and a high Ki-67 were correlated with a higher incidence of distant recurrence.

Conclusions

A systematic immunohistochemistry should be a key step in the therapeutic algorithm and could contribute to the identification of high-risk tumors.

Androgen receptor as potential therapeutic target in metastatic endometrial cancer

PURPOSE

The expression and involvement of estrogen (ER) and progesterone receptor (PR) is extensively studied in endometrial cancer. Androgen receptor (AR) is a hormone receptor less studied in female cancers, and we here aim to investigate the expression level of AR in endometrial cancer precursor lesions, primary tumors and metastases, and its potential as therapeutic target.

RESULTS

Expression of AR was observed in 93% of hyperplasias, but only in 41% of non-endometrioid tumors. Compared to estrogen and progesterone receptor AR is more commonly expressed in metastatic lesions, and AR status is discordant in primary and metastatic lesions in a large proportion of cases. AR protein level was significantly associated with survival (P < 0.001), and a calculated AR to ERα ratio identified a subgroup of patients with particular poor outcome. The anti-androgen enzalutamide may have a growth inhibitory effect in endometrial cancer cells based on experiments with primary endometrial tumor cells.

MATERIALS AND METHODS

718 primary endometrial cancers and 298 metastatic lesions (from 142 patients) were investigated for expression of AR in relation to survival, clinical and histopathological data. Protein levels were investigated by immunohistochemistry and reverse phase protein array; mRNA levels by DNA oligonucleotide microarray. The effect of androgen stimulation and inhibition was tested on primary endometrial tumor cells.

CONCLUSIONS

A large proportion of metastatic endometrial cancer lesions express AR, which may be a potential target in these patients. Treatment targeting AR may be of particular benefit in patients with high AR levels compared to ERα levels.

Unsupervised Clustering of Immunohistochemical Markers to Define High-Risk Endometrial Cancer

Considerable heterogeneity exists in outcomes of early endometrial cancer (EC) according to the type but also the histological grading. Our goal was to describe the immunohistochemical profiles of type I EC according to grades and type II EC, to identify groups of interacting proteins using principal component analysis (PCA) and unsupervised clustering. We studied 13 immunohistochemical markers (steroid receptors, pro/anti-apoptotic proteins, metalloproteinases (MMP) and tissue inhibitor of metalloproteinase (TIMP), and CD44 isoforms known for their role in endometrial pathology. Co-expressed proteins associated with the type, grade and outcome of EC were determined by PCA and unsupervised clustering. PCA identified three functional groups of proteins from 43 tissue samples (38 type I and 5 type II EC): the first was characterized by p53 expression; the second by MMPs, bcl-2, PR B and CD44v6; and the third by ER alpha, PR A, TIMP-2 and CD44v3. Unsupervised clustering found two main clusters of proteins, with both type I grade 3 and type II EC exhibiting the same cluster profile. PCA and unsupervised clustering of immunohistochemical markers in EC contribute to a better comprehension and classification of the disease.

Supervised Clustering of Adipokines and Hormonal Receptors Predict Prognosis in a Population of Obese Women with Type 1 Endometrial Cancer

Obesity is a major risk factor for endometrial cancer (EC). Yet, its impact on prognosis is controversial. Obesity is associated with metabolic and hormonal dysregulation as well as adipokines increase. The aim of this study was to characterize the expression of biological factors related to obesity within the tumor and evaluate their impact on prognosis. One hundred and thirty-six patients, including 55 obese patients, with endometrioid type I EC operated by total hysterectomy were included in this retrospective study conducted in a Tertiary teaching hospital between 2000 and 2013. Immunohistochemistry (IHC) study was performed on type I EC tumor samples using five adipokines (SPARC, RBP4 (Retinol Binding Protein 4), adiponectin, TNF α, IL-6) and hormonal receptors (estrogen receptor and progesterone receptor). Supervised clustering of immunohistochemical markers was performed to identify clusters that could be associated with prognostic groups. The prognosis of the obese population was not different from the prognosis of the general population. Adipokine expression within tumors was not different in these two populations. In obese population, we found three clusters where co-expression was associated with a recurrence group in comparison with a non-recurrence group and four clusters where co-expression was associated with the high risk FIGO (International Federation of Gynecology and Obstetrics) stage I group in comparison of low risk FIGO stage I group. While obesity does not appear as a prognostic factor in endometrioid type I EC, the co-expression of biological factors in IHC on hysterectomy specimens allowed to distinguish two prognostic groups in obese population.

Mice deleted for cell division cycle 73 gene develop parathyroid and uterine tumours: model for the hyperparathyroidism-jaw tumour syndrome

The hyperparathyroidism-jaw tumour (HPT-JT) syndrome is an autosomal dominant disorder characterized by occurrence of parathyroid tumours, often atypical adenomas and carcinomas, ossifying jaw fibromas, renal tumours and uterine benign and malignant neoplasms. HPT-JT is caused by mutations of the cell division cycle 73 (CDC73) gene, located on chromosome 1q31.2 and encodes a 531 amino acid protein, parafibromin. To facilitate in vivo studies of Cdc73 in tumourigenesis we generated conventional (Cdc73^+/-) and conditional parathyroid-specific (Cdc73^+/L/PTH-Cre and Cdc73^L/L/PTH-Cre) mouse models. Mice were aged to 18-21 months and studied for survival, tumour development and proliferation, and serum biochemistry, and compared to age-matched wild-type (Cdc73^+/+ and Cdc73^+/+/PTH-Cre) littermates. Survival of Cdc73^+/- mice, when compared to Cdc73^+/+ mice was reduced (Cdc73^+/-=80%; Cdc73^+/+=90% at 18 months of age, P<0.05). Cdc73^+/-, Cdc73^+/L/PTH-Cre and Cdc73^L/L/PTH-Cre mice developed parathyroid tumours, which had nuclear pleomorphism, fibrous septation and increased galectin-3 expression, consistent with atypical parathyroid adenomas, from 9 months of age. Parathyroid tumours in Cdc73^+/-, Cdc73^+/L/PTH-Cre and Cdc73^L/L/PTH-Cre mice had significantly increased proliferation, with rates >fourfold higher than that in parathyroid glands of wild-type littermates (P<0.0001). Cdc73^+/-, Cdc73^+/L/PTH-Cre and Cdc73^L/L/PTH-Cre mice had higher mean serum calcium concentrations than wild-type littermates, and Cdc73^+/- mice also had increased mean serum parathyroid hormone (PTH) concentrations. Parathyroid tumour development, and elevations in serum calcium and PTH, were similar in males and females. Cdc73^+/- mice did not develop bone or renal tumours but female Cdc73^+/- mice, at 18 months of age, had uterine neoplasms comprising squamous metaplasia, adenofibroma and adenomyoma. Uterine neoplasms, myometria and jaw bones of Cdc73^+/- mice had increased proliferation rates that were 2-fold higher than in Cdc73^+/+ mice (P<0.05). Thus, our studies, which have established mouse models for parathyroid tumours and uterine neoplasms that develop in the HPT-JT syndrome, provide in vivo models for future studies of these tumours.

New concepts for an old problem: the diagnosis of endometrial hyperplasia

BACKGROUND

Endometrial hyperplasia (EH) is a uterine pathology representing a spectrum of morphological endometrial alterations. It is predominantly characterized by an increase in the endometrial gland-to-stroma ratio when compared to normal proliferative endometrium. The clinical significance of EH lies in the associated risk of progression to endometrioid endometrial cancer (EC) and 'atypical' forms of EH are regarded as premalignant lesions. Traditional histopathological classification systems for EH exhibit wide and varying degrees of diagnostic reproducibility and, as a consequence, standardized patient management can be challenging.

OBJECTIVE AND RATIONALE

EC is the most common gynaecological malignancy in developed countries. The incidence of EC is rising, with alarming increases described in the 40-44-year-old age group. This review appraises the current EH classification systems used to stratify women at risk of malignant progression to EC. In addition, we summarize the evidence base regarding the use of immunohistochemical biomarkers for EH and discuss an emerging role for genomic analysis.

SEARCH METHODS

PubMed, Medline and the Cochrane Database were searched for original peer-reviewed primary and review articles, from January 2000 to January 2016. The following search terms were used: 'endometrial hyperplasia', 'endometrial intraepithelial neoplasia', 'atypical hyperplasia', 'complex atypical hyperplasia', 'biomarker', 'immunohistochemistry', 'progression', 'genomic', 'classification' and 'stratification'.

OUTCOMES

Recent changes to EH classification reflect our current understanding of the genesis of endometrioid ECs. The concept of endometrial intraepithelial neoplasia (EIN) as a mutationally activated, monoclonal pre-malignancy represents a fundamental shift from the previously held notion that unopposed oestrogenic stimulation causes ever-increasing hyperplastic proliferation, with accumulating cytological atypia that imperceptibly leads to the development of endometrioid EC. Our review highlights several key biomarker candidates that have been described as both diagnostic tools for EH and markers of progression to EC. We propose that, moving forwards, a 'panel' approach of combinations of the immunohistochemical biomarkers described in this review may be more informative since no single candidate can currently fill the entire role.

WIDER IMPLICATIONS

EC has historically been considered a predominantly postmenopausal disease. Owing in part to the current unprecedented rates of obesity, we are starting to see signs of a shift towards a rising incidence of EC amongst pre- and peri-menopausal woman. This creates unique challenges both diagnostically and therapeutically. Furthering our understanding of the premalignant stages of EC development will allow us to pursue earlier diagnosis and facilitate appropriate stratification of women at risk of developing EC, permitting timely and appropriate therapeutic interventions.

Epidemiology of Endometrial Carcinoma: Etiologic Importance of Hormonal and Metabolic Influences

Endometrial carcinoma is the most common gynecologic cancer in developed nations, and the annual incidence is projected to increase, secondary to the high prevalence of obesity, a strong endometrial carcinoma risk factor. Although endometrial carcinomas are etiologically, biologically, and clinically diverse, hormonal and metabolic mechanisms are particularly strongly implicated in the pathogenesis of endometrioid carcinoma, the numerically predominant subtype. The centrality of hormonal and metabolic disturbances in the pathogenesis of endometrial carcinoma, combined with its slow development from well-characterized precursors in most cases, offers a substantial opportunity to reduce endometrial carcinoma mortality through early detection, lifestyle modification, and chemoprevention. In this chapter, we review the epidemiology of endometrial carcinoma, emphasizing theories that link risk factors for these tumors to hormonal and metabolic mechanisms. Future translational research opportunities related to prevention are discussed.

Mig-6 Mouse Model of Endometrial Cancer

Endometrial cancer is a frequently occurring gynecological disorder. Estrogen-dependent endometrioid carcinoma is the most common type of gynecological cancer. One of the major pathologic phenomena of endometrial cancer is the loss of estrogen (E2) and progesterone (P4) control over uterine epithelial cell proliferation. P4 antagonizes the growth-promoting properties of E2 in the uterus. P4 prevents the development of endometrial cancer associated with unopposed E2 by blocking E2 actions. Mitogen inducible gene 6 (Mig-6, Errfi1, RALT, or gene 33) is an immediate early response gene that can be induced by various mitogens and common chronic stress stimuli. Mig-6 has been identified as an important component of P4-mediated inhibition of E2 signaling in the uterus. Decreased expression of MIG-6 is observed in human endometrial carcinomas. Transgenic mice with Mig-6 ablation in the uterus develop endometrial hyperplasia and E2-dependent endometrial cancer. Thus, MIG-6 has a tumor suppressor function in endometrial tumorigenesis. The following discussion summarizes our current knowledge of Mig-6 mouse models and their role in understanding the molecular mechanisms of endometrial tumorigenesis and in the development of therapeutic approaches for endometrial cancer.

The emerging role of long non-coding RNAs in endometrial cancer

The human genome is pervasively transcribed and approximately 98% of the genome is non-coding. Long non-coding RNAs (lncRNAs) are a heterogeneous group of RNA transcripts that are >200 nucleotides in length with minimal to no protein-coding potential. Similar to proteins, lncRNAs have important biological functions in both normal cells and disease states including many types of cancer. This review summarizes recent advances in our understanding of lncRNAs in cancer biology and highlights the potential for lncRNA as diagnostic biomarkers and therapeutics. Herein we focus on the poorly understood role of lncRNAs in endometrial cancer, the most common gynecologic malignancy in the developed world.

Expression of Nuclear Receptors and Cofacotrs in Human Endometrium and Myometrium

OBJECTIVE

To study the expression of nuclear receptors and cofactors in human endometrium and myometrium in proliferative and secretory phases of the menstrual cycle.

METHODS

Multiprobe ribonuclease protection assay and real-time reverse transcriptase polymerase chain reaction were used to quantitate mRNA levels of steroid receptors, vitamin D receptor (VDR), retinoic acid receptors (RAR), and cofactors AIB1 (amplified in breast cancer-1), CBP (cyclic adenosine monophosphate response element binding protein), pCAF (p300/CBP-associated factor), TIF2 (transcription intermediary factor-2), N-CoR (nuclear receptor corepressor), and SMRT (silencing mediator of repressed transcription). Cyclin A expression was analyzed to determine the proliferation status of the tissues.

RESULTS

The expression of androgen receptor, estrogen receptors alpha and beta, progesterone receptor, and RARalpha followed cyclin A expression. There was more abundant expression in the proliferative phase endometrium than in the secretory phase endometrium. Glucocorticoid receptor, VDR, RARbeta, and RARgamma were stably expressed during the menstrual cycle in both endometrium and myometrium. Cofactors N-CoR, SMRT, pCAF, CBP, TIF2, AIB1, and p300 mRNAs were expressed in all samples in both endometrium and myometrium. N-CoR, pCAF, AIB1, and p300 appeared not to be regulated when comparing proliferative and secretory phases of the cycle. Individual differences were found in the expression levels of both nuclear receptors and cofactors.

CONCLUSION

The menstrual cycle-dependent regulation of nuclear receptor expression was more apparent in the endometrium than in the myometrium, whereas cofactor expression was not cycle dependent. There were individual differences in the expression levels of different receptors and cofactors. In hormonal therapy these differences might result in different responses, depending on the patient as well as the ligand used.

Hormone Receptor Expression in Spontaneous Uterine Adenocarcinoma in Fischer 344 Rats

Most uterine cancers, the most common gynecological malignancies in women in developed countries, are hormone-dependent endometrial adenocarcinomas (EACs) that express estrogen and progesterone receptors. Although rat strains exist with a high spontaneous incidence of EAC, the Fischer 344 (F344) strain, previously one of the most commonly used strains in carcinogenicity testing, is not a high-incidence strain. To better understand the biology of this neoplasm, we assessed estrogen receptor α (ER), progesterone receptor (PR), and Ki-67 expression using immunohistochemistry in spontaneous EAC in 18 F344 rats used as control animals in 2-year National Toxicology Program bioassays. Of the 18 tumors, 9 were well-differentiated and 9 were poorly differentiated. Most tumors, 7/18, were ER+PR+, as observed in women. Of the remainder, 6/18 were ER+PR-, 2/18 were ER-PR+, and 3/18 were ER-PR-. Well-differentiated tumors were ER+ (8/9) more often than poorly differentiated tumors (5/9). The percentage of ER+ tumors (72%) in rats was similar to that seen in women, but rats less frequently had PR+ (50%) tumors than women. The heterogeneous estrogen and progesterone receptor immunophenotypes observed in F344 rats in this study highlight the importance of evaluating hormone receptor expression in animal models used for chemical evaluations.

Prognostic role of hormone receptors in endometrial cancer: a systematic review and meta-analysis

Background

The aim of this study was to summarize the global predicting role of hormone receptors for survival in endometrial cancer.

Methods

Eligible studies were identified and assessed for quality through multiple search strategies. Data were collected from studies comparing overall survival (OS), cancer-specific survival (CSS), or progression-free survival (PFS) in patients with elevated levels of estrogen receptor (ER), progesterone receptor (PR), or human epidermal growth factor receptor 2 (HER2) with those in patients with lower levels. The combined hazard ratios of ER, PR, and HER2 for survival were calculated.

Results

A total of 98 studies were included for meta-analysis (44 for ER, 38 for PR, and 16 for HER2). Higher levels of either ER or PR could significantly indicate better survival. The pooled hazard ratios (HRs) of ER for OS, CSS, and PFS were 0.75 (95 % CI, 0.68–0.83), 0.45 (95 % CI, 0.33–0.62), and 0.66 (95 % CI, 0.52–0.85), respectively. The combined HRs of PR for OS, CSS, and PFS reached 0.63 (95 % CI, 0.56–0.71), 0.62 (95 % CI, 0.42–0.93), and 0.45 (95 % CI, 0.30–0.68), respectively. In contrast, elevated levels of HER2 could predict worse outcome with a HR of 1.98 (95 % CI, 1.49–2.62) for OS, and a HR of 2.26 (95 % CI, 1.57–3.25) for PFS.

Conclusions

In patients with endometrial cancer, higher level of ER and PR predicted favorable survival, and increased level of HER2 was associated with poorer survival. All of the three hormone receptors had prognostic value for survival.

Loss of progesterone receptor links to high proliferation and increases from primary to metastatic endometrial cancer lesions

OBJECTIVE

In endometrial cancer loss of progesterone receptor (PR, gene name PGR) is associated with aggressive disease and altered response to hormonal treatment. The aim of this study was to investigate changes in PR expression level with disease progression, and explore whether differences in gene expression according to PR status can be linked to processes involved in cancer development elucidating new therapeutic opportunities.

METHODS

686 primary endometrial cancers and 171 metastatic lesions were investigated for PR expression in relation to clinical and histopathological data. Protein levels were investigated by immunohistochemistry and reverse phase protein array, and mRNA levels by DNA oligonucleotide microarray.

RESULTS

PR protein level was significantly associated with PGR mRNA expression (P<0.001) and patient survival (P<0.001). Loss of PR increased with disease progression, with 23% of the primary tumours and 76% of metastases demonstrating PR loss. Using a cell cycle progression signature score, PR loss was associated with increased proliferation for both oestrogen receptor (ER) positive and negative tumours. Through a Connectivity Map search, CDK inhibitors and other drugs with anti-proliferative effects were suggested in particular for treatment of patients with loss of PR.

CONCLUSION

Loss of PR in endometrial cancer is associated with increased proliferation, poor survival, and increases from primary to metastatic lesions. Based on expression profiles, CDK inhibitors may have activity in PR negative tumours, supporting further testing in clinical trials for patients with systemic endometrial cancer dependent on PR status.

Steroid hormone intervenes in the endometrial tumorigenesis of pten ablation

Background:

Endometrial cancer, the most common gynecological cancer, is closely associated with endometrial hyperplasia, unopposed estrogen exposure, and genetic alterations. Phosphatase and tensin homologue (PTEN) is a tumor suppressor genes completely lost or mutated in >50% of primary endometrioid endometrial cancers. Estrogen-dependent endometrioid carcinoma is the most common type of endometrial cancer. Progesterone is a hormone that antagonizes the growth-promoting properties of estrogen in the uterus. Progestin is used as a conservative endocrine treatment of early endometrial cancer in order to preserve fertility as well as a palliative measure for advanced-stage patients. Progesterone therapy has been shown to be effective in preventing endometrial cancer as well as controlling growth of the endometrium. However, the effectiveness of progestin for women with endometrial cancer is less clear.

Methods:

In order to understand the effect of steroid hormone on endometrial cancer progression, we used a mouse endometrial cancer model with conditional loss of Pten in the mouse uterus (PR^cre/+Pten^f/f, Pten^d/d). To assess the effect of steroid hormones, ovariectomized Pten^f/f and Pten^d/d mice were treated with estrogen or progesterone over a period of three month.

Results:

Uterine weight gain was significantly decreased in ovariectomized PR^cre/+Pten^f/f mice compared to intact PR^cre/+Pten^f/f mice. Ovariectomized PR^cre/+Pten^f/f mice treated with P4 or vehicle also exhibited decreased uterine cancer size compared with intact PR^cre/+Pten^f/f mice. Proliferation of ovariectomized PR^cre/+Pten^f/f mice treated with P4 is highly decreased compared to other groups. The levels of stromal progesterone receptor were highly increased in ovariectomized PR^cre/+Pten^f/f mice treated with P4 which resulted in decreased epithelial proliferation.

Conclusions:

These results suggest that P4 treatment significantly reduces tumor mass but does not affect cancer progression in PR^cre/+Pten^f/f mice.

Progesterone-targeted magnetic resonance imaging probes

Determination of progesterone receptor (PR) status in hormone-dependent diseases is essential in ascertaining disease prognosis and monitoring treatment response. The development of a noninvasive means of monitoring these processes would have significant impact on early detection, cost, repeated measurements, and personalized treatment options. Magnetic resonance imaging (MRI) is widely recognized as a technique that can produce longitudinal studies, and PR-targeted MR probes may address a clinical problem by providing contrast enhancement that reports on PR status without biopsy. Commercially available MR contrast agents are typically delivered via intravenous injection, whereas steroids are administered subcutaneously. Whether the route of delivery is important for tissue accumulation of steroid-modified MRI contrast agents to PR-rich tissues is not known. To address this question, modification of the chemistry linking progesterone with the gadolinium chelate led to MR probes with increased water solubility and lower cellular toxicity and enabled administration through the blood. This attribute came at a cost through lower affinity for PR and decreased ability to cross the cell membrane, and ultimately it did not improve delivery of the PR-targeted MR probe to PR-rich tissues or tumors in vivo. Overall, these studies are important, as they demonstrate that targeted contrast agents require optimization of delivery and receptor binding of the steroid and the gadolinium chelate for optimal translation in vivo.

Distribution of estrogen and progesterone receptors isoforms in endometrial cancer

Background

70–80% of sporadic endometrial carcinomas are defined as endometrioid carcinoma (EC). Early-stage, well differentiated endometrial carcinomas usually retain expression of estrogen and progesterone receptors (ER and PR, respectively), as advanced stage, poorly differentiated tumors often lack one or both of these receptors. Well-described EC prognosis includes tumor characteristics, such as depth of myometrial invasion. Therefore, in the current study, we evaluated the expression profile of ER and PR isoforms, including ER-α, PR-A and PR–B, in correlation to EC tumor histological depth.

Methods

Using immunohistochemistry and image analysis software, the expression of ER-α, PR-A, PR–B and Ki67 was assessed in endometrial stroma and epithelial glands of superficial, deep and extra-tumoral sections of 15 paraffin embedded EC specimens, and compared to 5 biopsies of non-malignant endometrium.

Results

Expression of PR-A and ER-α was found to be lower in EC compared to nonmalignant tissue, as the stromal expression was dramatically reduced compared to epithelial cells. Expression ratios of both receptors were significantly high in superficial and deep portions of EC; in non-tumoral portion of EC were close to the ratios of nonmalignant endometrium. PR-B expression was low in epithelial glands of EC superficial and deep portions, and high in the extra-tumoral region. Elevated PR-B expression was found in stroma of EC, as well.

Conclusions

The ratio of ER-α and PR-A expression in the epithelial glands and the stroma of EC biopsies may serve as an additional parameter in the histological evaluation of EC tumor.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1155060506119016

Multiple brain metastases in a patient with uterine papillary serous adenocarcinoma: Treatment options for this rarely seen metastatic brain tumor

Background:

Uterine papillary serous adenocarcinoma (UPSAC) occurs 10-fold less frequently than endometrial carcinoma, and is referred to type 2 endometrial adenocarcinoma. The prognosis of UPSAC is worse than that of type I endometrial carcinoma. Herein we report what is only the second case of UPSAC, but it should prove to be more informative than the first reported case.

Case Description:

A 71-year-old female had three different metastases in the brain; two of the metastases were located in the posterior fossa within the cerebellar parenchyma with perilesional edema, but no mass effect, and the third metastasis was located in the right frontal lobe, and caused hemispheric edema and subfalcine herniation. The lesion that caused mass effect was completely extirpated without any surgical complications. The patient's recovery was excellent. She is able to walk independently, and use her left hand and left arm. Her Karnofsky performance score 5 months postsurgery was 80/100.

Conclusion:

Based on the outcome in the presented case, we think that in any UPSAC patient with a metastatic brain tumor causing mass effect the symptomatic metastatic tumor must be removed, regardless of disease grade, to ensure optimal quality of life.

Critical tumor suppressor function mediated by epithelial Mig-6 in endometrial cancer

Endometrial cancer is preceded by endometrial hyperplasia, unopposed estrogen exposure, and genetic alterations, but the precise causes of endometrial cancer remain uncertain. Mig-6, mainly known as a negative regulator of the EGF receptor, is an important mediator of progesterone signaling in the uterus, where it mediates tumor suppression by modulating endometrial stromal-epithelial communications. In this study, we investigated the function of Mig-6 in the uterine epithelium using a tissue-specific gene knockout strategy, in which floxed Mig-6 (Mig-6(f/f)) mice were crossed to Wnt7a-Cre mice (Wnt7a(cre+)Mig-6(f/f)). Wnt7a(cre+)Mig-6(f/f) mice developed endometrial hyperplasia and estrogen-dependent endometrial cancer, exhibiting increased proliferation in epithelial cells as well as apoptosis in subepithelial stromal cells. We documented increased expression of NOTCH1 and BIRC3 in epithelial cells of Wnt7a(cre+)Mig-6(f/f) mice and decreased expression of the progesterone receptor (PR) in stromal cells. Progesterone therapy controls endometrial growth and prevents endometrial cancer, but the effectiveness of progesterone as a treatment for women with endometrial cancer is less clear. We noted that the hyperplasic phenotype of Wnt7a(cre+)Mig-6(f/f) mice was prevented by progesterone treatment, whereas this treatment had no effect in PR(cre/+)Mig-6(f/f) mice where Mig-6 was deleted in both the epithelial and stromal compartments of the uterus. In contrast, activation of progesterone signaling in the stroma regulated proliferation and apoptosis in the epithelium via suppression of ERα signaling. In summary, our results establish that epithelial Mig-6 functions as a critical tumor suppressor that mediates the ability of progesterone to prevent the development of endometrial cancer.

Histological and immunohistochemical profiles predict lymph node status in women with low-intermediate risk endometrial cancer

OBJECTIVE

The aim of this study was to build a model to predict the risk of lymph node metastases (LNM) in women with low- or intermediate-risk endometrial cancer (EC) using histological and immunohistochemical markers.

METHODS

Samples were collected from 68 women with low- or intermediate-risk EC. European Society of Medical Oncology (ESMO) risk group, lymphovascular space involvement (LVSI), immunostaining expressions of Estrogen receptor (ER) and Progesteron receptor (PR) were used to build a recursive partitioning model to predict final lymph node status.

RESULTS

The number of women with final low- and intermediate risk EC was 34 (50%) each. LVSI was present in 7 women with low-risk (20%) and 28 (80%) with intermediate-risk EC. Nineteen women (28%) had LNM at final histology. A lower immunostaining of ER (p=0.02) and PR (p=0.03) was found in women with LNM compared with those without. Women were correctly classified by the model in 87% of cases; among the 56 women without LNM that were predicted, 48 (86%) had no LNM at final histology. Among the 12 women with LNM predicted, 11 (92%) had LNM at final histology.

CONCLUSIONS

Our results show that lymph node status can be predicted with a relatively high accuracy in women with low- or intermediate-risk EC. This can help physicians to better adapt surgical staging and adjuvant therapies.

Retrospective analysis of prognostic variables and clinical outcomes in surgically staged intermediate risk endometrial carcinoma

OBJECTIVE

To identify independent prognostic variables for surgically staged intermediate risk endometrial carcinoma as defined by the Gynecologic Oncology Group 99 (GOG99) criteria.

STUDY DESIGN

Retrospective study of 239 patients with FIGO stage IB-occult IIB endometrioid type endometrial cancer, who were primarily treated with comprehensive staging surgery. Data were collected on clinicopathological variables, extent of primary surgery, postoperative adjuvant treatment, and patterns of recurrences. Kaplan-Meier survival curves were used to estimate disease free survival (DFS) and overall survival (OS), and multivariate Cox regression models were used to identify independent prognostic variables. The median follow-up time was 67 months (range, 12-183 months).

RESULTS

The 5-year DFS and OS were 91.0% and 93.0%, respectively. On univariate Kaplan-Meier analysis, age>60 years, deep myometrial invasion (MI), presence of lymph vascular invasion (LVSI), and negative progesterone receptor (PR) status were significantly associated with diminished 5-year DFS and OS. The univariate analysis on patterns of failures demonstrated that patients with older age or positive LVSI were more inclined to develop locoregional recurrence, while PR status and the depth of MI had a statistically significant impact on distant failure. On multivariate analysis, PR status, age, and the depth of MI were independent prognostic variables for 5-year DFS, and age was the only independent prognostic variable for 5-year OS. LVSI and age were independent prognostic variables for locoregional recurrence, while PR status and depth of MI were independent prognostic variables for distant recurrence.

CONCLUSIONS

Age, depth of MI, PR status and presence of LVSI are of independent prognostic value for intermediate risk endometrial cancer. The presence of these variables warrants consideration when deciding upon treatment strategies.

A phase II evaluation of gefitinib in the treatment of persistent or recurrent endometrial cancer: a Gynecologic Oncology Group study

BACKGROUND

A phase II trial was performed to evaluate the efficacy and safety of gefitinib in patients with persistent/recurrent endometrial cancer.

METHODS

Women with histologically confirmed persistent/recurrent endometrial cancer were treated with 500mg oral gefitinib daily until progression or severe toxicity, with progression-free survival (PFS) at six months as the primary endpoint. Tumor expression of total epidermal growth factor receptor (EGFR), estrogen receptor (ER), progesterone receptor A (PRA) and B (PRB), Ki67, pEGFR and activated extracellular signal-regulated kinase (pERK) were examined pre- and post-treatment. EGFR was sequenced, and serum concentrations of soluble EGFR (sEGFR) at baseline also were examined.

RESULTS

Of 29 patients enrolled, 26 were evaluable for efficacy and toxicity. Four patients experienced PFS ≥6 months, and one had a complete response which was not associated with an EGFR mutation. The concentration of sEGFR in pretreatment serum was positively correlated with overall survival (OS), but not with responsiveness to gefitinib in this small patient cohort. Expression of tumor biomarkers was not associated with PFS or OS. Co-expression of ER with PRA in primary and recurrent tumors, and pEGFR with pERK in primary tumors was observed.

CONCLUSIONS

This treatment regimen was tolerable but lacked sufficient efficacy to warrant further evaluation in this setting. The possible association between serum sEGFR concentrations and OS, and temporal changes in expression of pEGFR and pERK and the documented CR of one patient are interesting and warrant additional investigation.

Fatty acid synthase is a potential therapeutic target in estrogen receptor-/progesterone receptor-positive endometrioid endometrial cancer

OBJECTIVE

In the current study we investigated the clinicopathological significance of fatty acid synthase (FASN) expression and its relationship with estrogen receptor (ER) and progesterone receptor (PR) in endometrioid endometrial cancer.

METHODS

FASN expression in endometrioid endometrial cancer was assessed by immunohistochemistry using 108 paraffin-embedded tissue specimens and clinical data collected from a retrospective chart review. The specific FASN inhibitor C75 was used to analyze the relationship between FASN expression and cell growth as well as ER/PR expression in endometrioid endometrial cancer cell lines.

RESULTS

Positive FASN immunostaining was observed in 77.8% (84/108) of the tumors analyzed. Deep myometrial invasion was significantly and inversely correlated with positive FASN expression (p = 0.024). Positive ER (p = 0.018) and PR status (p = 0.012) was significantly correlated with positive FASN expression. Patients with positive FASN expression in endometrioid endometrial cancer tissues tended to have a favorable progression-free/overall survival (p = 0.127 and p = 0.087, respectively). Ishikawa cells with high FASN expression also showed high expression of ER/PR, while HEC1B cells had low expression levels of both FASN and ER/PR. FASN inhibition by C75 (10 µM) significantly reduced ER/PR expression compared with control dimethyl sulfoxide treatment of Ishikawa cells. The growth of Ishikawa cells having positive FASN and ER/PR expression was significantly inhibited in the presence of C75 or FASN small-interfering RNA compared to HEC1B cells that lacked FASN and ER/PR expression.

CONCLUSION

The current findings suggest that there may be cross talk between the ER/PR and FASN signaling pathways that modulate ER/PR activation and could play a role in endometrioid endometrial cancer pathogenesis.

Clinicopathological and prognostic impact of human epidermal growth factor receptor type 2 (HER2) and hormone receptor expression in uterine papillary serous carcinoma

Uterine papillary serous carcinoma (UPSC) is a rare and aggressive variant of endometrial carcinoma. Little is known about the pathological and biological features of this tumor. Human epidermal growth factor receptor 2 (HER2) and hormone receptor (HR) expression have an important role in tumor behavior and clinical outcome, but their relevance in UPSC is not clear. In the present study, the immunohistochemical expression of HER2 and HR was assessed in 27 patients with Stage I disease, 13 with Stage II disease, 25 with Stage III disease, and 6 with Stage IV disease. Correlations between HER2 and HR expression and the clinicopathological parameters of UPSC were evaluated using Cox's univariate and multivariate analyses. For all patients, the 5-year recurrence-free survival (RFS) and overall survival (OS) rates were 51% and 66%, respectively; in patients with Stage I, II, III and IV disease, the RFS and OS were 67%/81%, 59%/77%, 43%/54% and 0%/0%, respectively. Of all 71 patients, 14% (10/71) were positive for HER2 and 52% (37/71) were positive for HR. Overexpression of HER2 was correlated with lower OS (P = 0.01), whereas HR overexpression was correlated with higher OS (P = 0.008). In multivariate models, HER2, HR, and histologic subtype were identified as independent prognostic indicators for RFS (P = 0.022, P = 0.018, and P = 0.01, respectively), but HR was the only independent factor associated with OS (P = 0.044). Thus, HER2 and HR are prognostic variables in UPSC, with HR an independent prognostic factor for OS.

Selected immunohistochemical prognostic factors in endometrial cancer

OBJECTIVE

The objectives of this study were to assess the immunohistochemical expression of p53, bcl-2, c-erbB-2, Ki-67, estrogen (ER) and progesterone (PR) receptors, matrix metalloproteinase-7 and -26 (MMP-7 and MMP-26) in endometrial cancer patients and to assess the relation between steroid receptor positivity and other markers.

DESIGN

Experimental prospective study.

SETTING

Department of Obstetrics and Gynecology, Department of Genetics, Department of Pathology, Palacký University Medical School and University Hospital Olomouc.

METHODS

We studied 144 cases of primary untreated endometrial carcinoma in which the p53, bcl-2, c-erbB-2, Ki-67, ER, PR, MMP-7, and MMP-26 antigens were investigated with the use of immunohistochemical methods. We evaluated the correlations among immunohistochemical staining and the age, International Federation of Gynecology and Obstetrics stage, grading, depth of invasion, and metastatic spread to lymph nodes.

RESULTS

Mean age was 65.7 years (range, 34-90 years). p53, bcl-2, c-erbB-2, Ki-67, ER, and PR were positive in 35 (24.3%), 100 (69.4%), 41 (28.4%), 65 (45.1%), 115 (79.8%), and 127 (88.1%) cases, respectively. Matrix metalloproteinases were evaluated in a group of 70 patients, wherein MMP-7 was positive in 33 patients (47.1%) and MMP-26 was positive in 40 patients (57.1%). The expression of MMP-7 decreased with higher patient age. p53 and Ki-67 overexpression was found to be related to poor differentiation. Immunostaining for bcl-2 correlated with the positivity of steroid receptors status, whereas immunostaining for c-erbB-2 correlated inversely with ER-positive group of cases.

CONCLUSIONS

The overexpression of p53 and Ki-67 seems to indicate a more malignant phenotype, whereas bcl-2 expression in dependence of steroid receptor positivity could contribute to the identification of high-risk tumors.

Functional oestrogen receptor α imaging in endometrial carcinoma using 16α-[¹⁸F]fluoro-17β-oestradiol PET

PURPOSE

To investigate the correlation between uptake of 16α-[(18)F]fluoro-17β-oestradiol (FES) and expression of oestrogen receptors as well as other related immunohistochemistry markers, positron emission tomography (PET) was performed in patients with endometrial carcinoma before surgery.

METHODS

Nineteen patients with endometrioid adenocarcinoma underwent preoperative PET studies with FES and 2-[(18)F]fluoro-2-deoxy-D: -glucose (FDG). Standardized uptake values (SUVs) for each tracer and the regional FDG to FES SUV ratio were calculated using images after coregistration. PET values were compared with postoperative stage, differentiation grade and immunohistochemical scores including oestrogen receptor subtypes (ERα, ERβ), progesterone receptor B (PR-B), Ki-67 and glucose transporter 1 (GLUT1).

RESULTS

FES uptake showed a significantly positive correlation with expression of ERα. The FDG to FES ratio showed a significantly negative correlation with expression of ERα and PR-B. The FES uptake and FDG to FES ratio did not correlate with expression of ERβ, Ki-67 or GLUT1. FDG uptake was not correlated with any of the immunohistochemical scores. The PR-B score was strongly correlated with the ERα score. Well-differentiated carcinoma (grade 1) showed a significantly higher FES uptake and significantly lower FDG to FES ratio than moderately or poorly differentiated carcinoma (grade 2-3). None of the PET parameters were significantly different between advanced-stage carcinoma (≥ stage IB) and early-stage carcinoma (IA) based on the Féderation International de Gynécologie et d'Obstétrique (FIGO) staging classification. Differentiation grade was the most closely correlated parameter to FES uptake and FDG to FES ratio by multivariate analyses.

CONCLUSION

FES PET combined with FDG would be useful for non-invasive evaluation of ERα distribution, as well as ERα function, which reflects differentiation grade in endometrial carcinoma.

Hypermethylation of SOX2 Promoter in Endometrial Carcinogenesis

This paper aimed at investigating the expression and methylation profiles of SOX2, a gene coding for the stem cell-related transcription factor SOX2, in endometrial carcinomas. By methylation-specific polymerase chain reaction (MS-PCR), the methylation status of SOX2 promoter region in 72 endometrial carcinomas and 12 normal endometrial samples was examined. Methylated allele was found in 37.5% (27/72) of endometrial carcinomas but only in 8.3% (1/12) of normal endometrial, significantly more frequent in cancers (P = .0472). SOX2 mRNA level was significantly reduced in endometrial carcinoma compared with nonneoplastic endometrium (P = .045). A significant correlation between SOX2 mRNA expression and hypermethylation of SOX2 was found (P = .024). Hypermethylation of SOX2 tended to be more frequently found in type II serous or clear cell adenocarcinoma. SOX2 methylation was also significantly correlated with shorter survival of patients (P = .046). In conclusion, epigenetic mechanisms may play a crucial role on the transcriptional regulation of SOX2 and loss of SOX2 expression may be related to endometrial carcinogenesis.

Comparative evaluation of estrogen and progesterone receptor expression with connexins 26 and 43 in endometrial cancer

Progression of numerous neoplasms could involve alterations of gap junction channels composed of connexins (Cxs). Disorders of expression and cellular displacement of Cxs were also found in endometrial cancer. Gap junctional intercellular communication can be regulated by wide array of agents, for instance, growth factors, oncogenes, and steroid hormones. Nevertheless, expressions of Cxs and progesterone receptor (PR) were not compared in human tissues. This study focused on assessment of expression of estrogen receptor alpha (ERalpha) and PRs in relation to the expression of Cx26 and Cx43 in 88 cases of endometrial cancer and analysis of these proteins' expression in comparison with anatomoclinical features. Positive ERalpha and PR nuclear staining was present in 66 (75%) and 60 (68.2%) of all studied tumors, respectively. Positive correlation was found between expression of PR and histopathologic type of tumor (P = 0.026), and negative correlation was drawn with grading (G) (P = 0.002). There were positive reactions to Cx26 and Cx43 of mainly cytoplasmic location in 60 (68.2%) and 66 (75%) of studied cancers, respectively. Progesterone receptor expression correlated negatively with Cx26 in endometrial cancers (P = 0.016, r = -0.256). Moreover, ERalpha expression positively correlated with PR expression (P < 0.001, r = 0.678). On the ground of our findings, disorders of Cx expression and altered distribution pattern occur during endometrial carcinogenesis, and it seems that PR could participate in this fact. Loss of functional gap junctions may occur because of the aberrant expression and localization of Cx26 and Cx43 in endometrial cancer.

The Synergistic Effect of Conditional Pten Loss and Oncogenic K-ras Mutation on Endometrial Cancer Development Occurs via Decreased Progesterone Receptor Action

Endometrial cancer is the most common gynecological cancer. Estrogen-dependent endometrioid carcinoma is the most common type of endometrial cancer, and alterations in the expression of PTEN and K-ras have been associated with this disease. To study the roles of Pten and K-ras in endometrial cancer, we generated Pten ablation and oncogenic K-ras mutation in progesterone receptor positive cells (PR^cre/+Pten^f/fK-ras^G12D). Double mutant mice dramatically accelerated the development of endometrial cancer compared to a single mutation of either gene. Histological analysis showed that all of the 1-month old double mutant female mice developed endometrial cancer with myometrial invasion. The expression of PR was downregulated in double mutant mice compared to a single mutation of either gene which resulted in decreased suppression of estrogen signaling. Therefore, these results suggest a synergistic effect of dysregulation of the Pten and K-ras signaling pathways during endometrial tumorigenesis.

Expression of oestrogen receptors, ERalpha, ERbeta, and ERbeta variants, in endometrial cancers and evidence that prostaglandin F may play a role in regulating expression of ERalpha

Background

Endometrial cancer is the most common gynaecological malignancy; risk factors include exposure to oestrogens and high body mass index. Expression of enzymes involved in biosynthesis of oestrogens and prostaglandins (PG) is often higher in endometrial cancers when compared with levels detected in normal endometrium. Oestrogens bind one of two receptors (ERα and ERβ) encoded by separate genes. The full-length receptors function as ligand-activated transcription factors; splice variant isoforms of ERβ lacking a ligand-binding domain have also been described. PGs act in an autocrine or paracrine manner by binding to specific G-protein coupled receptors.

Methods

We compared expression of ERs, progesterone receptor (PR) and cyclooxygenase-2 (COX-2) in stage 1 endometrial adenocarcinomas graded as well (G1), moderately (G2) or poorly (G3) differentiated (n ≥ 10 each group) using qRTPCR, single and double immunohistochemistry. We used endometrial adenocarcinoma cell lines to investigate the impact of PGF2α on expression of ERs and PR.

Results

Full length ERβ (ERβ1) and two ERβ variants (ERβ2, ERβ5) were expressed in endometrial cancers regardless of grade and the proteins were immunolocalised to the nuclei of cells in both epithelial and stromal compartments. Immunoexpression of COX-2 was most intense in cells that were ERα^neg/low. Expression of PR in endometrial adenocarcinoma (Ishikawa) cell lines and tissues broadly paralleled that of ERα. Treatment of adenocarcinoma cells with PGF2α reduced expression of ERα but had no impact on ERβ1. Cells incubated with PGF2α were unable to increase expression of PR mRNA when they were incubated with E2.

Conclusion

We have demonstrated that ERβ5 protein is expressed in stage 1 endometrial adenocarcinomas. Expression of three ERβ variants, including the full-length protein is not grade-dependent and most cells in poorly differentiated cancers are ERβ^pos/ERα^neg. We found evidence of a link between COX-2, its product PGF2α, and expression of ERα and PR that sheds new light on the cross talk between steroid and PG signalling pathways in this disease.

Current challenges in clinical management of endometrial cancer

Endometrial cancer remains a management challenge. Improved understanding of the mechanisms of carcinogenesis may enable better understanding of biologic behavior and guide therapy. Improvements in diagnostic imaging, radiation delivery systems, and systemic therapies potentially can improve outcomes while minimizing morbidity. Novel strategies for screening and prevention also hold promise for reducing incidence and mortality of this disease.

The prognostic importance of proliferative activity and oestrogen receptor expression in stage I endometrial carcinomas

The purpose of this study was to evaluate the prognostic significance of steroid hormone receptor proliferation index in endometrial adenocarcinoma. In this study, the correlation between oestrogen receptor expression, proliferation index and FIGO grade, age, myometrial invasion, tumour size and menopause status was evaluated in 40 patients with endometrial carcinoma. For this purpose, all tumours were stained immunohistochemically with oestrogen receptor and Ki-67 monoclonal antibodies. Oestrogen receptor expression and proliferation indices were found to be statistically associated with grade, age, menopausal status, vascular invasion and tumour size ( p < 0.001). Quantitative assessment of tumour proliferation and expression of oestrogen receptor were found to be important prognostic indicators in endometrial adenocarcinoma.

Diagnostic and prognostic impact of osteopontin expression in endometrial cancer

The role of osteopontin as a biomarker in endometrial cancer has not been conclusively established. We evaluated the expression and potential of osteopontin as a biomarker for endometrial cancer. Real-time polymerase chain reaction and immunohistochemistry revealed osteopontin overexpression in endometrial cancer. The plasma osteopontin level in endometrial cancer was significantly higher than in healthy controls (P< 0.001). In FIGO stage I endometrial cancer, osteopontin correctly identified 18 of 29 cases (62.1%) that were not detected by CA125. By Cox multivariate analysis, osteopontin positivity was an independent prognostic factor for disease-free survival (hazard ratio = 3.18, P= 0.035).

Immunohistochemical labelling of steroid receptors in normal and malignant human endometrium

For several years it was generally believed that only a single estrogen receptor (ER) and progesterone receptor (PR) existed. However, the discovery of a new ER (ERbeta) with specificity for estrogens has induced new insights in the estrogen signalling system. Moreover, PR is expressed as two major isoforms, PR-A and PR-B that arise from alternative transcriptional starting sites within the same gene. Although PR-A and PR-B were thought to occur in similar amounts, it is now clear that they are differentially expressed and thus have distinct functions in several human tissues, including human endometrium. The ER and PR expression and distribution pattern might play an important role in normal endometrial function and pathogenesis and the expression and relationship of the two distinct ER's and PR's could be of essential clinical implications. Moreover, the imbalance in ERalpha/ERbeta expression and the PR-A/PR-B ratio might play an important role in endometrial transition and subsequently influence endometrial pathogenesis. The knowledge of the pattern of steroid receptors in human endometrial tissue is of extreme importance, since it might start a new field in hormone therapy of endometrial cancer.

Endometrioid adenocarcinoma arising in adenomyosis: elucidation by periodic magnetic resonance imaging evaluations

There are several case reports of adenocarcinomas developing within adenomyosis. However, there is no report demonstrating the natural course from adenomyosis to adenocarcinoma. We report a patient (a 41-year-old Japanese woman) who was observed every 6 months after being diagnosed with adenomyosis at our University Hospital. Although she went through menopause at age 51, she occasionally complained subsequently of abnormal genital bleeding. Eleven years after the initial diagnosis, endometrial cytology revealed the presence of malignant cells. Pelvic magnetic resonance imaging (MRI) demonstrated replacement of the adenomyotic lesion by a poorly demarcated lesion, compared to the findings on prior MRI. Consequently, we performed a modified radical hysterectomy and pelvic lymph node dissection, under a presumptive diagnosis of adenocarcinoma arising in adenomyosis. Histological diagnosis revealed an endometrioid adenocarcinoma (G3) transformed from adenomyotic epithelium, which was classified, according to the International Federation of Gynecology and Obstetrics, as stage Ic, pT1cN0M0. In this patient, periodic MRI evaluations, in conjunction with pathological examination, identified the transformation from adenomyosis to adenocarcinoma.

Prognostic significance of oestrogen receptor alpha (ERα) and beta (ERβ), progesterone receptor A (PR-A) and B (PR-B) in endometrial carcinomas

The expression of the classic steroid receptors ERalpha and PR-A has been correlated with stage, histological grade and survival in endometrial cancer. Endometrial cancer samples (293) were immunohistochemically analysed with monoclonal antibodies against the four steroid receptors. The loss of ERalpha, PR-A and PR-B resulted in a poorer survival in endometrial cancer patients, while ERbeta expression did not demonstrate any correlations with several analysed clinicopathological characteristics and did not affect survival. Additionally, multivariate survival analysis demonstrated that PR-B was a significant independent prognostic factor for cause-specific survival. In contrast, although ERalpha and PR-A showed a significant association between different endometrial histological subtypes and grading, both receptors were not independent factors with survival in endometrial carcinoma patients. Therefore, the PR-B immunostaining might be used as an easy, simple and highly efficient marker to identify high-risk patients and may aid in the selection of patients for a more aggressive adjuvant therapy.

Aromatase inhibitor-induced bone mineral loss and its prevention by bisphosphonate administration in postmenopausal breast cancer patients

AIM

To investigate aromatase inhibitor-induced bone mineral loss and its prevention by bisphosphonate administration in postmenopausal breast cancer patients.

METHODS

Subjects were 17 postmenopausal breast cancer patients (mean age, 63.3 +/- 9.9 years) receiving non-steroidal aromatase inhibitor (AI; anastrozole, 1 mg daily) only and 10 such patients (mean age, 65.0 +/- 5.1 years) receiving AI + bisphosphonate (risedronate sodium, 2.5 mg daily) for 6 months. All of the subjects had undergone surgical resection and had positive estrogen receptor tumor status. Age, age at menopause, years since menopause, height, weight, and body mass index (Wt/Ht(2)) were recorded. Lumbar spine (L2-4) bone mineral density (BMD), T-, and Z-scores were assessed on dual-energy X-ray absorptiometry before and after therapy.

RESULTS

In the AI-only group BMD, T-, and Z-scores significantly decreased from the baseline during the 6-month therapy period (P < 0.05). Mean decreases in L2-4 BMD and Z-score were 2.5% and 3.0%, respectively. In the AI + bisphosphonate group, however, BMD, T-, and Z-scores significantly increased from the baseline values (P < 0.01). Mean increases in L2-4 BMD and Z-score were 4.5% and 3.3%, respectively.

CONCLUSION

AI carries a potential risk of bone mineral loss despite the short therapy duration. Bisphosphonate has a preventive effect on this loss.

Down-regulation of the progesterone receptor by the methylation of progesterone receptor gene in endometrial cancer cells

Progesterone plays an important role in the regulation of normal endometrium function by binding to progesterone receptor (PR). In endometrial cancer, however, PR is always down-regulated. Previous reports showed that methylation in the promoter region of the PR gene may be responsible for PRB isoform repression. However, the CpG islands in the exon region of the PR gene are much richer and longer than in the promoter region. We hypothesize that methylation in the exon region may also take part in the down-regulation of the PR gene. The methylation status of the first exon of the PR gene in endometrial cell cultures was investigated. Aberrant methylation patterns were observed in the first exon of PR gene, and the methylation density is correlated with the differentiation of different types of endometrial cancer cells. DNA methyltransferase (DNMT) and histone deacetylase inhibitor 5-aza-2'-deoxycytidine (ADC), as well as trichostatin A (TSA), which reverses PR gene expression, were also studied. A combination of ADC and TSA resulted in synergistic effects in inducing PR expression, down-regulation of DNMT1 and DNMT3A, and could also have antigrowth effect on endometrial cancer cells by inducing apoptosis.

Relationship of estrogen and progesterone receptors to clinical outcome in metastatic endometrial carcinoma: A Gynecologic Oncology Group Study

INTRODUCTION

The goal of this study was to explore the relationship between the expression of hormone receptors in metastatic endometrial tumors and clinical response to daily tamoxifen citrate and intermittent weekly medroxyprogesterone acetate.

STUDY DESIGN

Patients with measurable recurrent or advanced endometrial cancer were enrolled on a clinical trial, Gynecologic Oncology Group Study 119. A pretreatment tumor biopsy was obtained and subjected to immunohistochemical analyses. Estrogen receptor-alpha (ER-alpha) and progesterone receptor (PR) were assessed on frozen tissues, and PR isoforms A and B were detected on fixed tissues. The receptors were scored using a semi-quantitative HSCORE, with a cut off greater than 75 considered positive.

RESULTS

Of the 60 eligible patients, 45 had evaluable tissues for all receptors. For ER, 40% of the cases were positive; for PR, 45% were positive. The sub-cellular distribution of PRA was exclusively nuclear, and 16% of the tumors demonstrated positive staining. PRB was nuclear and cytoplasmic, with 22% of the tumors staining for nuclear PRB and 36% of the tumors staining for cytoplasmic PRB. ER and PR from frozen tissues and PRA and cytoplasmic PRB from fixed tissues significantly decreased with increasing tumor grade. The co-expression of ER-alpha with PR from the frozen tissues (r=0.68, p<0.001) and PRA (r=0.58, p<0.001) from the fixed tissues was statistically significant. The ER HSCORE was related to both response and overall survival; there was no statistically significant correlation of PR with clinical response in this small number of patients.

CONCLUSION

ER-alpha measured in metastatic endometrial carcinoma tissue prior to hormonal therapy was statistically significantly related to clinical response to daily tamoxifen and intermittent medroxyprogesterone acetate.