Estrogen action in human ovarian cancer

Immunohistochemical markers of prognosis in adult granulosa cell tumors of the ovary - a review

BACKGROUND

Granulosa cell tumors (GCT) are rare malignant ovarian tumors. The two subtypes, adult and juvenile granulosa cell tumors, differ in clinical and molecular characteristics. GCT are low-malignant tumors and are generally associated with favorable prognosis. However, relapses are common even years and decades after diagnosis. Prognostic and predictive factors are difficult to assess in this rare tumor entity. The purpose of this review is to provide a comprehensive overview of the current state of knowledge on prognostic markers of GCT to identify patients with a high risk of recurrence.

METHODS

Systematic research for adult ovarian granulosa cell tumors and prognosis revealed n = 409 English full text results from 1965 to 2021. Of these articles, n = 35 were considered for this review after title and abstract screening and topic-specific matching. A specific search for pathologic markers with prognostic relevance for GCT identified n = 19 articles that were added to this review.

RESULTS

FOXL2 mutation and FOXL2 mRNA were inverse and immunohistochemical (IHC) expression of CD56, GATA-4 and SMAD3 was associated with reduced prognosis. IHC analysis of estrogen receptor, Anti-Mullerian hormone (AMH) and inhibin was not associated with prognosis for GCT. Analyses of mitotic rate, Ki-67, p53, β-catenin and HER2 revealed inconsistent results.

Insights Into the Role of Epigenetic Factors Determining the Estrogen Response in Estrogen-Positive Ovarian Cancer and Prospects of Combining Epi-Drugs With Endocrine Therapy

Ovarian cancer is one of the most lethal malignancies. The population at the risk is continually on the rise due to the acquired drug resistance, high relapse rate, incomplete knowledge of the etiology, cross-talk with other gynecological malignancies, and diagnosis at an advanced stage. Most ovarian tumors are thought to arise in surface epithelium somehow in response to changes in the hormonal environment. Prolonged treatment with hormone replacement therapy (HRT) is also considered a contributing factor. Estrogens influence the etiology and progression of the endocrine/hormone-responsive cancers in a patient-specific manner. The concept of hormonal manipulations got attention during the last half of the 20th century when tamoxifen was approved by the FDA as the first selective estrogen receptor modulator (SERM). Endocrine therapy that has been found to be effective against breast cancer can be an option for ovarian cancer. It is now established that global changes in the epigenetic landscape are not only the hallmark of tumor development but also contribute to the development of resistance to hormone therapy. A set of functionally related genes involved in epigenetic reprogramming are controlled by specific transcription factors (TFs). Thus, the activities of TFs mediate important mechanisms through which epigenetic enzymes and co-factors modify chromatin for the worst outcome in a site-specific manner. Furthermore, the role of epigenetic aberrations involving histone modifications is established in ovarian cancer pathogenesis. This review aims to provide insights on the role of key epigenetic determinants of response as well as resistance to the hormone therapy, the current status of research along with its limitations, and future prospects of epigenetic agents as biomarkers in early diagnosis, prognosis, and personalized treatment strategies. Finally, the possibility of small phytoestrogenic molecules in combination with immunotherapy and epi-drugs targeting ovarian cancer has been discussed.

Reduced PAX2 expression in murine fallopian tube cells enhances estrogen receptor signaling

High-grade serous ovarian cancer (HGSOC) is thought to progress from a series of precursor lesions in the fallopian tube epithelium (FTE). One of the preneoplastic lesions found in the FTE is called a secretory cell outgrowth (SCOUT), which is partially defined by a loss of paired box 2 (PAX2). In the present study, we developed PAX2-deficient murine cell lines in order to model a SCOUT and to explore the role of PAX2 loss in the etiology of HGSOC. Loss of PAX2 alone in the murine oviductal epithelium (MOE) did not induce changes in proliferation, migration and survival in hypoxia or contribute to resistance to first line therapies, such as cisplatin or paclitaxel. RNA sequencing of MOE PAX2shRNA cells revealed significant alterations in the transcriptome. Silencing of PAX2 in MOE cells produced a messenger RNA expression pattern that recapitulated several aspects of the transcriptome of previously characterized human SCOUTs. RNA-seq analysis and subsequent qPCR validation of this SCOUT model revealed an enrichment of genes involved in estrogen signaling and an increase in expression of estrogen receptor α. MOE PAX2shRNA cells had higher estrogen signaling activity and higher expression of putative estrogen responsive genes both in the presence and absence of exogenous estrogen. In summary, loss of PAX2 in MOE cells is sufficient to transcriptionally recapitulate a human SCOUT, and this model revealed an enrichment of estrogen signaling as a possible route for tumor progression of precursor lesions in the fallopian tube.

PARAGON (ANZGOG-0903): a phase 2 study of anastrozole in asymptomatic patients with estrogen and progesterone receptor-positive recurrent ovarian cancer and CA125 progression

Objective

A subset of patients with recurrent ovarian cancer (ROC) may benefit from antiestrogen therapy with higher response rates reported in tumors that are strongly estrogen receptor (ER)-positive (ER⁺). PARAGON is a basket trial that incorporates 7 phase 2 trials investigating the activity of anastrozole in patients with ER⁺ and/or progesterone receptor (PR)-positive (PR⁺) recurrent/metastatic gynecological cancers.

Methods

Postmenopausal women with ER⁺ and/or PR⁺ ROC, who were asymptomatic and had cancer antigen 125 (CA125) progression after response to first line chemotherapy, where chemotherapy was not clinically indicated. Patients received anastrozole 1 mg daily until progression or unacceptable toxicity.

Results

Fifty-four patients were enrolled (52 evaluable). Clinical benefit at three months (primary endpoint) was observed in 18 patients (34.6%; 95% confidence interval [CI]=23%–48%). Median progression-free survival (PFS) was 2.7 months (95% CI=2.1–3.1). The median duration of clinical benefit was 6.5 months (95% CI=2.8–11.7). Most patients progressed within 6 months of starting anastrozole but 12 (22%) continued treatment for longer than 6 months. Anastrozole was well tolerated. In the exploratory analysis, ER histoscores and the intensity of ER staining did not correlate with clinical benefit rate or PFS.

Conclusion

A subset of asymptomatic patients with ER⁺ and/or PR⁺ ROC and CA125 progression had durable clinical benefit on anastrozole, with acceptable toxicity. Anastrozole may delay symptomatic progression and the time to subsequent chemotherapy. The future challenge is to identify the subset of patients most likely to benefit from an aromatase inhibitor and whether the clinical benefit could be increased by the addition of other agents.

Role of Lipoproteins in the Microenvironment of Hormone-Dependent Cancers

The tumor microenvironment (TME) is an attractive target to develop novel strategies for hormone-dependent cancers. Several molecules in the TME can favor tumor development and progression, including lipoproteins. Lipoproteins are taken up by cancer cells, providing them with cholesterol and fatty acids. Cholesterol regulates cell signaling and it is converted into a series of bioactive metabolites, including hormones. The conflicting results of epidemiological and interventional studies suggest that the local availability of lipoproteins in the TME is more relevant for cancer biology than their circulating levels. Thus, reducing lipoprotein uptake and stimulating cell cholesterol efflux to high-density lipoproteins (HDLs) can represent a novel adjuvant strategy for cancer management. HDL-like particles can also act as drug delivery systems for tumor targeting.

Risk of ovarian cancer in women treated with ovarian stimulating drugs for infertility

BACKGROUND

This is an updated version of the original Cochrane Review published in the Cochrane Library in 2013 (Issue 8) on the risk of ovarian cancer in women using infertility drugs when compared to the general population or to infertile women not treated. The link between fertility drugs and ovarian cancer remains controversial.

OBJECTIVES

To evaluate the risk of invasive ovarian cancer and borderline ovarian tumours in women treated with ovarian stimulating drugs for subfertility.

SEARCH METHODS

The original review included published and unpublished observational studies from 1990 to February 2013. For this update, we extended the searches from February 2013 to November 2018; we evaluated the quality of the included studies and judged the certainty of evidence by using the GRADE approach. We have reported the results in a Summary of findings table to present effect sizes across all outcome types.

SELECTION CRITERIA

In the original review and in this update, we searched for randomised controlled trials (RCTs) and non-randomised studies and case series including more than 30 participants.

DATA COLLECTION AND ANALYSIS

At least two review authors independently conducted eligibility and 'Risk of bias' assessments and extracted data. We grouped studies based on the fertility drug used for two outcomes: borderline ovarian tumours and invasive ovarian cancer. We conducted no meta-analyses due to expected methodological and clinical heterogeneity.

MAIN RESULTS

We included 13 case-control and 24 cohort studies (an additional nine new cohort and two case-control studies), which included a total of 4,684,724 women.Two cohort studies reported an increased incidence of invasive ovarian cancer in exposed subfertile women compared with unexposed women. One reported a standardised incidence ratio (SIR) of 1.19 (95% confidence interval (CI) 0.54 to 2.25) based on 17 cancer cases. The other cohort study reported a hazard ratio (HR) of 1.93 (95% CI 1.18 to 3.18), and this risk was increased in women remaining nulligravid after using clomiphene citrate (HR 2.49, 95% CI 1.30 to 4.78) versus multiparous women (HR 1.52, 95% CI 0.67 to 3.42) (very low-certainty evidence). The slight increase in ovarian cancer risk among women having between one and three cycles of in vitro fertilisation (IVF) was reported, but this was not clinically significant (P = 0.18). There was no increase in risk of invasive ovarian cancer after use of infertility drugs in women with the BRCA mutation according to one cohort and one case-control study. The certainty of evidence as assessed using GRADE was very low.For borderline ovarian tumours, one cohort study reported increased risk in exposed women with an SIR of 3.61 (95% CI 1.45 to 7.44), and this risk was greater after treatment with clomiphene citrate (SIR 7.47, 95% CI 1.54 to 21.83) based on 12 cases. In another cohort study, the risk of a borderline ovarian tumour was increased, with an HR of 4.23 (95% CI 1.25 to 14.33), for subfertile women treated with IVF compared with a non-IVF-treated group with more than one year of follow-up. A large cohort reported increased risk of borderline ovarian tumours, with HR of 2.46 (95% CI 1.20 to 5.04), and this was based on 17 cases. A significant increase in serous borderline ovarian tumours was reported in one cohort study after the use of progesterone for more than four cycles (risk ratio (RR) 2.63, 95% CI 1.04 to 6.64). A case-control study reported increased risk after clomiphene citrate was taken, with an SIR of 2.5 (95% CI 1.3 to 4.5) based on 11 cases, and another reported an increase especially after human menopausal gonadotrophin was taken (odds ratio (OR) 9.38, 95% CI 1.66 to 52.08). Another study estimated an increased risk of borderline ovarian tumour, but this estimation was based on four cases with no control reporting use of fertility drugs. The certainty of evidence as assessed using GRADE was very low.However, although some studies suggested a slight increase in risks of ovarian cancer and borderline ovarian tumour, none provided moderate- or high-certainty evidence, as summarised in the GRADE tables.

AUTHORS' CONCLUSIONS

Since the last version of this review, only a few new relevant studies have provided additional findings with supporting evidence to suggest that infertility drugs may increase the risk of ovarian cancer slightly in subfertile women treated with infertility drugs when compared to the general population or to subfertile women not treated. The risk is slightly higher in nulliparous than in multiparous women treated with infertility drugs, and for borderline ovarian tumours. However, few studies have been conducted, the number of cancers is very small, and information on the dose or type of fertility drugs used is insufficient.

Chemopreventive Effects of ROS Targeting in a Murine Model of BRCA1-Deficient Breast Cancer

There remains great interest in practical strategies to limit the elevated risks of familial breast and ovarian cancers driven by BRCA1 mutation. Here, we report that limiting the production of reactive oxygen species (ROS) is sufficient to reduce DNA lesions and delay tumorigenesis in a murine model of BRCA1-deficient breast cancer. We documented a large amount of endogenous estrogen oxidative metabolites in the mammary gland of the model, which induced DNA adducts and apurinic/apyrimidinic sites associated with DNA double-strand breaks and genomic instability. Repressing estrogen oxidation via antioxidant treatments reduced oxidative DNA lesions and delayed the onset of mammary tumors. Overall our work suggests an answer to the long-standing question of why germline BRCA1 mutations cause tissue-specific tumors, in showing how tissue-specific, ROS-induced DNA lesions create a nongenetic force to promote mammary tumors in BRCA1-deficient mice. Our findings create a rationale for evaluating suitable antioxidant modalities as a chemopreventive strategy for familial breast cancer. Cancer Res; 77(2); 448-58. ©2016 AACR.

Does ovarian stimulation for IVF increase gynaecological cancer risk? A systematic review and meta-analysis

The aim of this study was to evaluate whether ovarian stimulation for IVF increases the risk of gynaecological cancer, including ovarian, endometrial, cervical and breast cancers, as an independent risk factor. A systematic review and meta-analysis was conducted. Clinical trials that examined the association between ovarian stimulation for IVF and gynaecologic cancers were included. The outcomes of interest were incidence rate of gynaecologic cancers. Twelve cohort studies with 178,396 women exposed to IVF were included; 10 studies were used to analyse ovarian (167,640 women) and breast (151,702 women) cancers, and six studies were identified in the analysis of endometrial (116,672 women) and cervical cancer (114,799 women). Among these studies, 175 ovarian, 48 endometrial, 502 cervical and 866 cases of breast cancer were reported. The meta-analysis found no significant association between ovarian stimulation for IVF and increased ovarian, endometrial, cervical and breast cancer risk (odds ratio [OR] 1.06, 95% confidence interval [CI] 0.85 to 1.32; OR 0.97, 95% CI 0.58 to 1.63; OR 0.43, 95% CI 0.30 to 0.60; OR 0.69, 95% CI 0.63 to 0.76, respectively). Ovarian stimulation for IVF, therefore, does not increase the gynaecologic cancer risk, whether hormone-dependent endometrial and breast cancer or non-hormone-dependent ovarian and cervical cancer.

Immunohistochemical expression of ERα, ERβ, and TFF1 in type I and II ovarian tumors

Surface epithelial tumors of the ovary are no longer considered as a single disease but are divided into types I and II on the basis of their molecular features, cell of origin, and their behavior. A possible direct action of gonadal steroids on ovarian carcinogenesis has been suggested. The current information about the possible role of TFF1 in ovarian tumors,, together with its relationship to the estrogen receptor (ER) status, is insufficient. The aim of this study was to investigate ERα, ERβ, and TFF1 expression in type I and II ovarian tumors and their correlation with clinicopathologic parameters of each type. The present study was carried out on 97 ovarian tumors [20 benign, 15 borderline, and 62 malignant (36 type I and 26 type II tumors)]. ERα expression was significantly in favor of type II tumors (P=0.04), whereas high TFF1 expression was significantly in favor of type I tumors (P=0.02). ERα and ERβ showed a significant positive correlation in benign cases (P=0.004) and in type I tumors (P=0.006), but not in type II tumors. In type I tumors, the expression of ERα was correlated with serous carcinoma (P=0.002) and bilaterality (P=0.05), whereas TFF1 was correlated with mucinous carcinoma (P=0.02), unilaterality (P=0.04), early FIGO staging (P=0.01), and a low mitotic count (P=0.03). A high ERβ:ERα H score ratio was associated with advanced FIGO staging in both type I (P=0.05) and type II tumors (P=0.009). The difference in the expression of ERα and TFF1 between type I and II tumors may be indicative of the difference in their origin and molecular pathway. The ERβ:ERα ratio is more important in determining the net result of ER effects than the evaluation of each receptor separately, and the high ratio may promote progression to advanced stage in type I and II ovarian tumors. High TFF1 expression in ovarian mucinous carcinoma may indicate that their mucinous differentiation is toward an intestinal type rather than an endocervical type. TFF1 expression in ovarian tumors seems to occur independent of the status of the ER.

Risk of ovarian cancer in women treated with ovarian stimulating drugs for infertility

BACKGROUND

The use of assisted reproductive techniques is increasing, but the possible link between fertility drugs and ovarian cancer remains controversial.

OBJECTIVES

To evaluate the risk of ovarian cancer in women treated with ovulation stimulating drugs for subfertility.

SEARCH METHODS

We searched for published and unpublished observational studies from 1990 to February 2013. The following databases were used: the Cochrane Gynaecological Cancer Collaborative Review Group's Trial Register, Cochrane Central Register of Controlled Trials (CENTRAL) 2013, Issue 1, MEDLINE (to February week 4 2013), EMBASE (to 2013 week 09) and databases of conference abstracts. We also scanned reference lists of retrieved articles. The search was not restricted by language of publication.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) and non-randomised studies, and case series including more than 30 participants, reporting on women with exposure to ovarian stimulating drugs for treatment of subfertility and histologically confirmed borderline or invasive ovarian cancer.

DATA COLLECTION AND ANALYSIS

At least two review authors independently conducted eligibility and 'Risk of bias' assessment, and extracted data. We grouped studies based on the fertility drug used for two outcomes: borderline ovarian tumours and invasive ovarian cancer. We expressed findings as adjusted odds ratio (OR), risk ratio (RR), hazard ratio (HR) or crude OR if adjusted values were not reported and standardised incidence ratio (SIR) where reported. We conducted no meta-analyses due to expected methodological and clinical heterogeneity.

MAIN RESULTS

We included 11 case-control studies and 14 cohort studies, which included a total of 182,972 women.Seven cohort studies showed no evidence of an increased risk of invasive ovarian cancer in subfertile women treated with any drug compared with untreated subfertile women. Seven case-control studies showed no evidence of an increased risk, compared with control women of a similar age. Two cohort studies reported an increased incidence of invasive ovarian cancer in subfertile women treated with any fertility drug compared with the general population. One of these reported a SIR of 5.0 (95% confidence interval (CI) 1.0 to 15), based on three cancer cases, and a decreased risk when cancer cases diagnosed within one year of treatment were excluded from the analysis(SIR 1.67, 95% CI 0.02 to 9.27). The other cohort study reported an OR of 2.09 (95% CI 1.39 to 3.12), based on 26 cases.For borderline ovarian tumours, exposure to any fertility drug was associated with a two to three-fold increased risk in two case-control studies. One case-control study reported an OR of 28 (95% CI 1.5 to 516), which was based on only four cases. In one cohort study, there was more than a two-fold increase in the incidence of borderline tumours compared with the general population (SIR 2.6, 95% CI 1.4 to 4.6) and in another the risk of a borderline ovarian tumour was HR 4.23 (95% CI 1.25 to 14.33) for subfertile women treated with in vitro fertilisation (IVF) compared with a non-IVF treated group with more than one year of follow-up.There was no evidence of an increased risk in women exposed to clomiphene alone or clomiphene plus gonadotrophin, compared with unexposed women. One case-control study reported an increased risk in users of human menopausal gonadotrophin (HMG)(OR 9.4, 95% CI 1.7 to 52). However, this estimate is based on only six cases with a history of HMG use.

AUTHORS' CONCLUSIONS

We found no convincing evidence of an increase in the risk of invasive ovarian tumours with fertility drug treatment. There may be an increased risk of borderline ovarian tumours in subfertile women treated with IVF. Studies showing an increase in the risk of ovarian cancer had a high overall risk of bias, due to retrospective study design, lack of accounting for potential confounding and estimates based on a small number of cases. More studies at low risk of bias are needed.

The potential prognostic value of cathepsin D protein in serous ovarian cancer

OBJECTIVES

Overexpression of a ubiquitous lysosomal aspartyl protease cathepsin D (cath-D) is involved in the progression of certain cancer types. This study investigated the prognostic value of the cath-D expression and its association with other known clinicopathological parameters in serous ovarian carcinoma.

MATERIALS AND METHODS

Cath-D was detected by immunohistochemistry in 49 serous ovarian carcinomas and compared to 50 benign serous ovarian tumors. The results were correlated with clinicopathological characteristics and survival outcomes.

RESULTS

In both cath-D positive benign and malignant serous ovarian tumors, a specific granular cytoplasmic staining was observed in both epithelial and stromal cells. Cath-D expression levels were higher in serous ovarian carcinomas than in benign tumors (P < 0.01). Cath-D expression in tumor epithelial cells correlated with mesenchymal cell expression (P < 0.001). The cath-D expression levels of tumor epithelial cells correlated with residual tumor size (P = 0.027) and was not related to other factors (P > 0.05). Patients with higher cath-D expression in epithelial cells had longer disease-free survival time (DFST; P = 0.025) and overall survival time (OST; P = 0.030). Through the Cox regression test, we found that the response to treatment (P < 0.001), pathological stage (P < 0.001), and peritoneal cytology results (P = 0.018) were independent effect factors for DFST. The expression level of cath-D in epithelial cells (P = 0.025), response to treatment (P < 0.001), pathological stage (P = 0.001), and peritoneal cytology results (P = 0.002) were independent effect factors for OST.

CONCLUSION

This showed that cath-D was an indicator of malignancy in serous ovarian carcinoma. It was expressed more highly in serous ovarian carcinoma than benign serous ovarian tumor. Additionally, our results suggested that high expression of cath-D in tumor epithelial cells was a favorable survival prognostic factor for serous ovarian carcinoma.

Borderline ovarian tumors diagnosed during pregnancy exhibit a high incidence of aggressive features: results of a French multicenter study

BACKGROUND

The purpose of the current study was to evaluate the characteristics of borderline ovarian tumors (BOTs) diagnosed during pregnancy.

PATIENTS AND METHODS

We conducted a retrospective multicenter study of 40 patients with BOTs diagnosed during pregnancy between 1997 and 2009 at five tertiary universitary departments of Gynecology and Obstetrics and one French cancer center. The medical records were reviewed to determine surgical procedure, histology, restaging surgery and recurrence.

RESULTS

Mean patient age was 30.2 ± 5.4 years. Most BOTs were diagnosed during the first trimester of pregnancy (62%). Salpingo-oophorectomy (N = 24) was more frequently performed than cystectomy (N = 11) during pregnancy (P = 0.01). Only two patients had an initial complete staging. BOTs were mucinous, serous and mixed in 48%, 42% and 10% of patients, respectively. Twenty-one percent of mucinous BOTs exhibited intraepithelial carcinoma or microinvasion. Forty-seven percent of serous BOTs exhibited micropapillary features, noninvasive implants or microinvasion. Restaging surgery performed in 52% patients resulted in upstaging in 24% of cases. Recurrence rate in patients with serous BOT with micropapillary features or peritoneal implants was 7.5%.

CONCLUSIONS

BOTs diagnosed during pregnancy exhibit a high incidence of aggressive features and are rarely completely staged initially. Given this setting, up-front salpingo-oophorectomy should be considered and restaging planned.

[Ovarian carcinogenesis: recent and past hypotheses]

Ovarian carcinogenesis and the early stages of malignant transformation are limited because of the lack of a candidate precursor. There have been several proposed hypotheses: first, ovary and the ovarian surface epithelium and more recently observations have increasingly focused attention of the Fallopian tube. Moreover, molecular genetic analysis has designed two main pathways of tumorogenesis. In this review, we discuss the different and perhaps complementary hypotheses about ovarian carcinogenesis.

A useful cell system for studying the regulation of 17HSD/KSR type 2 activity and expression in ovarian epithelial cancer

17β-Hydroxysteroid dehydrogenase/17-ketosteroid reductase (17HSD/KSR) activity and 17HSD/KSR types 1, 2, 4, and 5 mRNA levels were characterized in ovarian cancer cell lines derived from patients unexposed to radiation or chemotherapy. Activity was at the limit of detection in TOV-112D and TOV-21G cells. Activity in OV-90 was comparable to that in human placental tissue, was predominantly microsomal and was 17HSD/KSR type 2-like in substrate specificity and inhibition patterns. In monolayers, conversion of testosterone (T) to androstenedione (A) was 12-fold greater than that of A to T. Reduction of fetal bovine serum to 0.3% in the culture medium had no effect on 17β-HSD activity. Significant levels of type 1 and type 2 mRNAs were observed in OV-90 while only trace amounts were detected in TOV-21G. In contrast, type 4 mRNA levels were comparable for OV-90 and TOV-21G. Type 5 mRNA was detected in both cell lines but its level in OV-90 was twice that of TOV-21G. In OV-90, the type 2-like activity was predominant even though the type 5 mRNA level was 2.5-fold higher than that of the type 2. OV-90 cells may be a useful system for studying the regulation of 17HSD/KSR type 2 activity and expression in ovarian epithelial cancer.

Relationship between epidemiologic risk factors and hormone receptor expression in ovarian cancer: results from the Nurses' Health Study

Hormone receptor expression in tumors may offer etiologic information for ovarian cancer, particularly in light of known associations with hormonal and reproductive risk factors. Tissue microarrays constructed from 157 paraffin-embedded blocks of epithelial ovarian tumors collected from participants in the Nurses' Health Study were stained for estrogen receptor-alpha (ERalpha) and progesterone receptor (PR). We examined receptor expression by invasion, grade, and histologic subtype. Multivariate unconditional logistic regression was used to evaluate whether hormonal, reproductive, and anthropometric risk factors were differentially associated with the risk of developing receptor-positive or receptor-negative ovarian tumors compared with controls. PR-expressing tumors were less likely to be invasive (P = 0.05) and more likely to be of a lower grade (P < 0.001) and stage (P = 0.007) compared with PR- tumors. ERalpha status was not associated with any pathologic features of the tumor (P > 0.34). Increasing age, being postmenopausal, and postmenopausal hormone use were associated with an increased risk of developing ERalpha+, but not ERalpha- (P(heterogeneity) = 0.001, 0.06, and 0.06, respectively) and PR-, but not PR+, tumors (P(heterogeneity) = 0.08, 0.003, and 0.40, respectively), whereas height was only associated with the risk of developing PR- disease (P(heterogeneity) = 0.08). There were no clear risk differentials with OC use, parity, body mass index, or physical activity. Reproductive and hormonal risk factors are associated with subgroups of ovarian cancer defined by histologic subtype or ERalpha and PR status. These finding support specific models of hormone mediated triggers of ovarian cancer.

Use of fertility drugs and risk of ovarian cancer: Danish Population Based Cohort Study

OBJECTIVE

To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women.

DESIGN

Population based cohort study.

SETTING

Danish hospitals and private fertility clinics.

PARTICIPANTS

54,362 women with infertility problems referred to all Danish fertility clinics during 1963-98. The median age at first evaluation of infertility was 30 years (range 16-55 years), and the median age at the end of follow-up was 47 (range 18-81) years. Included in the analysis were 156 women with invasive epithelial ovarian cancer (cases) and 1241 subcohort members identified in the cohort during follow-up in 2006.

MAIN OUTCOME MEASURE

Effect of four groups of fertility drugs (gonadotrophins, clomifene citrate, human chorionic gonadotrophin, and gonadotrophin releasing hormone) on overall risk of ovarian cancer after adjustment for potential confounding factors.

RESULTS

Analyses within cohort showed no overall increased risk of ovarian cancer after any use of gonadotrophins (rate ratio 0.83, 95% confidence interval 0.50 to 1.37), clomifene (1.14, 0.79 to 1.64), human chorionic gonadotrophin (0.89, 0.62 to 1.29), or gonadotrophin releasing hormone (0.80, 0.42 to 1.51). Furthermore, no associations were found between all four groups of fertility drugs and number of cycles of use, length of follow-up, or parity.

CONCLUSION

No convincing association was found between use of fertility drugs and risk of ovarian cancer.

Estrogen receptor gene amplification occurs rarely in ovarian cancer

Amplification of the gene encoding estrogen receptor-alpha occurs in about 20% of breast cancers and is an important mechanism for estrogen receptor overexpression in this tumor type. In ovarian cancer, overexpression of estrogen receptor protein has been described in more than two thirds of cases. To study a potential role of estrogen receptor-alpha gene amplification for estrogen receptor overexpression in ovarian cancer, a tumor tissue microarray containing 428 ovarian cancers was analyzed by fluorescence in situ hybridization for estrogen receptor-alpha gene amplification and immunohistochemistry for estrogen receptor expression. The estrogen receptor-alpha gene status was successfully determined in 243 of 428 arrayed cancers. Estrogen receptor gene amplification was found in 5 of 243 (2%) of tumors. Amplification levels were usually low, with 4-8 estrogen receptor-alpha gene copies. However, one case had a high-level amplification, with more than 30 estrogen receptor-alpha gene copies. All five amplified tumors were estrogen receptor positive, with 3 of 5 tumors showing highest (Allred score, 7-8) estrogen receptor levels. The data demonstrate that estrogen receptor-alpha amplification occurs only rarely in ovarian cancer.

Pigment epithelium-derived factor is estrogen sensitive and inhibits the growth of human ovarian cancer and ovarian surface epithelial cells

Epithelial ovarian carcinoma is the most lethal gynecological cancer. However, little is known about the molecular mechanisms underlying the disease development and progression. In this study, we found that the expression of pigment epithelium-derived factor (PEDF) was greatly reduced in ovarian tumors and in ovarian cancer cell lines when compared with their normal precursor, ovarian surface epithelium (OSE). In addition, we showed that exogenous PEDF inhibited the growth of cultured human OSE as well as ovarian cancer cell lines, whereas targeted inhibition of endogenous PEDF using small interfering RNA or neutralizing PEDF antibody promoted the growth of these cells, confirming that the growth-inhibitory effect was PEDF specific. We also report for the first time that estrogen is an important upstream regulator of PEDF in human OSE. Treatment of the cultured cells with 17 beta-estradiol (E2) inhibited the expression of PEDF protein and mRNA in a dose- and time-dependent manner, which could be reversed by the specific estrogen receptor antagonist, ICI 182,780, indicating that the regulation was estrogen receptor-mediated. We further showed that this down-regulation of PEDF gene transcription was a direct, primary effect of E2. E2 promoted OSE and ovarian cancer cell growth, whereas simultaneous treatment with E2 and PEDF abrogated the estrogenic growth stimulation of these cells. This study is the first to demonstrate a role of PEDF in OSE biology and ovarian cancer and suggests that the loss of PEDF may e of relevance in carcinogenesis.

Induction of ovulation and ovarian cancer: a critical review of the literature

OBJECTIVE

To critically examine the possible association between ovulation-inducing drugs and ovarian cancer.

DESIGN

Medline literature review and cross-reference of published data.

RESULTS(S)

The studies that have adjusted for the effects of confounding factors such as duration of oral contraceptive use and number of pregnancies have noted an increased risk of ovarian cancer among infertile women who remain childless despite long periods of unprotected intercourse. Whether such women are at risk due to the primary basis for their infertility or factors such as ovulation-inducing drugs, has been the subject of several studies. Overall, the findings on ovarian cancer (especially invasive epithelial and non-epithelial) risk associated with fertility drug treatment are reassuring. However, a stronger association between fertility drug use and borderline tumors of the ovary has been observed.

CONCLUSION(S)

Despite the overall reassuring findings of the available studies, there is a need for well-designed clinical trials to understand the possible carcinogenic effects of the ovulation-inducing drugs.

Targeting Breast and Prostate Cancers Through Their Hormone Receptors1

A targeted treatment that effectively destroys human breast, prostate, ovarian, and testicular cancer cells that express luteinizing hormone/chorionic gonadotropin (LH/CG) receptors has been developed. The treatment consists of a conjugate of a membrane-disrupting lytic peptide (Hecate, Phor14, or Phor21) and a 15-amino acid segment of the beta chain of CG. Because these conjugates act primarily by destroying cell membranes, their effects are independent of cell proliferation. The conjugates are relatively small molecules, are rapidly metabolized, and are not antigenic. In a series of independent experiments conducted in three different laboratories, the validity of the concept has been established, and it has been shown that the LH/CG receptor capacity of the cancer cells is directly related to the sensitivity of the lytic peptide conjugates. Sensitivity to the drugs can be increased by pretreating prostate or breast cancer cells with FSH or estradiol to up-regulate LH/CG receptors. A series of 23 in vivo experiments involving a total of 1630 nude mice bearing xenografts of human prostate or breast cancer cells showed convincingly that all three lytic peptide-betaCG compounds were highly effective in destroying tumors and reducing tumor burden. Hecate-betaCG was less effective in mice bearing ovarian epithelial cancer cell xenografts, but was highly effective in treating granulosa cell tumors in transgenic mice. In addition, Hecate-betaCG and Phor14-betaCG were highly effective in targeting and destroying prostate and breast cancer cell metastases in the presence or absence of the primary tumors. Although effective in vitro, neither Hecate nor Phor14 alone were effective in reducing primary tumor volume or burden in nude mice bearing prostate or breast cancer xenografts.

Mutational analysis of the estrogen receptor-alpha gene in familial ovarian cancer

AIM

The genetic region of 6q25 containing the estrogen receptor-alpha (ER-alpha) gene is lost in a significant number of ovarian tumors. The aim of this study was to identify how inherited variation in the ER-alpha gene contributes to susceptibility to familial ovarian cancer.

METHODS

DNA obtained from 18 cases of familial ovarian cancer without mutation of the BRCA1 and BRCA2 genes, 20 cases with BRCA1 mutation, 20 cases of sporadic ovarian cancer, and 19 controls were screened for mutations in the coding region of the ER-alpha gene using direct sequencing.

RESULTS

Two germline missense variants at codons 307 [GCC(Ala)-->TCC(Ser)] and 347 [ACC(Thr)-->TCC(Ser)] were detected in two unrelated cases with BRCA1 mutation, but not in all other cases tested. Three polymorphisms in codon 10 [TCT-->TCC(Ser)], codon 325 [CCC-->CCG(Pro)], and codon 594 [ACA-->ACG(Thr)] were identified in this series, and a higher frequency of the allele TCC at codon 10 and a lower frequency of the allele CCG at codon 325 were observed in familial cases without BRCA1 mutation, compared with those in familial cases with BRCA1 mutation, in both the sporadic cases and in the controls.

CONCLUSIONS

We could not detect pathogenic mutations of the ER-alpha gene in ovarian cancer cases without BRCA1 mutation. However, association analyses of two polymorphisms suggest that the ER-alpha gene or a gene located close to the ER-alpha locus might be related to susceptibility of familial ovarian cancer without BRCA1 mutation.

Immunolocalization of nuclear transcription factors, DAX-1 and Ad4BP/SF-1, in human common epithelial ovarian tumors: correlations with StAR and steroidogenic enzymes in epithelial ovarian carcinoma

Intratumoral steroidogenesis is considered to play important roles in the biologic behavior of common epithelial ovarian carcinoma. Recent studies have demonstrated the important roles of Ad4BP/SF-1 and DAX-1 in regulation of steroidogenesis. In this study, we evaluated DAX-1, Ad4BP/SF-1, StAR, and steroidogenic enzyme expressions and their correlations in epithelial ovarian carcinomas to evaluate the possible roles of these factors in regulation of intratumoral steroid metabolism and/or production. Immunolocalization of DAX-1, Ad4BP/SF-1, StAR, and steroidogenic enzymes were examined in 90 epithelial ovarian carcinomas. mRNA expression of these proteins was evaluated using real-time polymerase chain reaction (PCR) in 23 cases for further characterization. DAX-1 and Ad4BP/SF-1 immunoreactivity was detected predominately in the nuclei of tumor cells, whereas that of StAR and steroidogenic enzymes was present in the cytoplasm. We detected a significant positive correlation between StAR and steroidogenic enzymes immunoreactivity and Ad4BP/SF-1 and statistically inversed correlation with DAX-1. A positive statistical correlation was detected between intratumoral stromal Ad4BP/SF-1 immunoreactivity and clinicopathologic parameters of carcinoma patients. Results of real-time PCR analysis were correlated with those of immunohistochemical studies. The status of intratumoral DAX-1, Ad4BP/SF-1, and StAR and steroidogenic enzymes in epithelial cells and intratumoral stromal cells of epithelial ovarian carcinoma may contribute in the progression and/or aggressiveness of these tumors.

Expression of estrogen receptor-related receptors, a subfamily of orphan nuclear receptors, as new tumor biomarkers in ovarian cancer cells

A subfamily of orphan receptors, estrogen receptor-related receptors (ERRs), has been demonstrated to modulate the transcription of some estrogen responsive genes via variant estrogen response elements (EREs). This study was conducted to determine whether human ERRalpha, ERRbeta, and ERRgamma might be involved in the tumorigenesis of ovarian cancer. RT-PCR was performed to analyze the expression of hERRalpha, hERRbeta, hERRbeta-2, and hERRgamma mRNA in five ovarian cancer cell lines as well as 33 samples of ovarian cancer and 12 samples of normal ovary. Serum CA-125 levels were also analyzed in all samples by ELISA. Progression-free survival and overall survival of patients with different expression of ERRs were analyzed by the Kaplan-Meier method. To analyze the subcellular localization of ERRalpha, a green fluorescent protein (GFP)-reporter plasmid of hERRalpha was constructed and transfected into the ovarian cancer cell line OVCAR-3. Expression of hERRalpha-GFP fusion protein was observed in the nucleus of OVCAR-3 ovarian cancer cell lines. We observed increased expression of hERRalpha mRNA (P = 0.020) and hERRgamma mRNA (P = 0.045) in ovarian cancers compared to normal ovaries. In contrast, hERRbeta was only observed in 9.1% of ovarian cancers. We found a positive correlation between the serum CA-125 levels and hERRalpha expression (P = 0.012), but not hERRbeta and hERRgamma expression. Survival analysis showed that the hERRalpha-positive group has a reduced overall survival (P = 0.015), and the ERRgamma-positive group has a longer progression-free survival (P = 0.020). In multivariate analysis, expression of hERRalpha was an independent prognostic factor for poor survival (relative risk, 3.032; 95% CI, 1.27-6.06). Based on our results, ERRs may play an important role in ovarian cancer. hERRalpha may represent a biomarker of poor prognosis, and hERRgamma may be a new therapeutic target in ovarian cancer.

Estradiol-induced ezrin overexpression in ovarian cancer: a new signaling domain for estrogen

We have for the first time exposed estrogen's role in the epithelial ovarian cancer (OVCA) metastatic cascade and discovered that it is related to the induction of ezrin over-expression. 17beta Estradiol (E2) was administered to SKOV3 (ERalpha>beta) and DOV13 (ERalpha<ERbeta) OVCA cells in serum-and phenol red-free medium fortified with transferrin and insulin. Incubated cells that penetrated Matrigel membranes were counted, immunostained and analyzed for immunoreactive ezrin. E2 induced an invasive phenotype with translocation of ezrin to cell edges, including pseudopodia and ruffles. A strong correlation was found between ezrin expression and Matrigel penetration induced by E2. Increases in cell number and ezrin expression were confirmed by flask incubations. E2 stimulation of OVCA cell proliferation, motility and Matrigel penetration was dose-related and raloxifene or tamoxifen blocked E2's effect, supporting an ER action. This previously unreported effect of estrogen on ezrin expression may play a role in the clinical course of estrogen-sensitive cancers and other normal or diseased cell actions.

StAR and progesterone producing enzymes (3beta-hydroxysteroid dehydrogenase and cholesterol side-chain cleavage cytochromes P450) in human epithelial ovarian carcinoma: immunohistochemical and real-time PCR studies

Steroidogenic acute regulatory protein (StAR), P450 side-chain cleavage enzyme (P450scc) and 3 beta-hydroxysteroid dehydrogenase enzyme (3beta-HSD) are all involved in the transport of cholesterol and production of progesterone. In situ production of sex steroids including progesterone have been considered to play important roles in pathogenesis and/or development of common epithelial ovarian carcinomas. In this study, StAR, P450scc, and 3beta-HSD were immunolocalized in 100 cases of ovarian carcinoma and results were then correlated with clinicopathological and prognostic parameters of individual patients including status of progesterone receptor (PR) in tumor cells. Results of immunohistochemistry were further characterized by real-time PCR analysis in 20 cases of epithelial ovarian carcinomas in which frozen tissues were available for examination. StAR, P450scc, and 3beta-HSD immunoreactivity was detected predominately in the cytoplasm of carcinoma cells. Results of real-time PCR analysis were correlated with those of immunohistochemical studies. StAR, P450scc, and 3beta-HSD H scores demonstrated significant inversed statistical correlation with FIGO stage, residual size of the tumor, and Ki67 LI. A positive statistically significant correlation was detected between StAR H score and PR-B LI. Multivariate statistical analysis demonstrated that the status of intratumoral StAR, FIGO stage, and residual tumor size all turned out to be independent prognostic factors for the clinical outcome of the patient. The presence of StAR, a cholesterol transporter for steroidogenesis in human epithelial ovarian carcinoma, may reflect the ability of these tumors to produce progesterone in situ that could influence biological behavior of these tumors, especially through progesterone dependent inhibition of tumor cell proliferation.

Estradiol derivatives bearing sulfur-containing substituents at the 11beta or 7alpha positions: versatile reagents for the preparation of estrogen conjugates

Estradiol derivatives bearing HS-, HSCH(2)-, HSCH(2)CH(2)-, MeS-, MeSCH(2)-, MeSCH(2)CH(2)-, or PhCH(2)SCH(2)CH(2)-groups at the 11beta position or an HS-group at the 7alpha position have been synthesized, and their binding affinity to the estrogen receptor (ER) determined. Nearly all of these substituted estrogens retain high binding affinity, and at the 11beta position, the sulfur atom has an effect on ER binding that is similar to that of a carbon atom. These thiol derivatives are promising intermediates for the preparation of a variety of estradiol conjugates. The methyl sulfides, in particular, might potentially be developed as (11)C-labeled agents for imaging ER-positive tumors by positron emission tomography.

Expression of nuclear receptor coregulators in ovarian stromal and epithelial tumours

Granulosa cell tumours of the ovary (GCT) exhibit high expression of estrogen receptor beta (ERbeta). A role for estrogen receptors in these tumours may depend on altered co-activator expression. This study examines the expression of the co-activators SRC-1a/e, SRC-2, SRC-3, SRA, and the corepressors NCoR and SMRT in GCT, epithelial ovarian tumours and normal ovary. No significant difference in the expression of SRC-1, SRC-2, SRC-3 or NCoR and SMRT was found. In particular, there was no correlation of co-activator expression with ERbeta expression. There was a significant upregulation in the expression of the novel RNA co-activator SRA in the serous tumours compared with the other tumour types and normal ovary. The findings suggest that ERbeta may require co-activators, other than members of the SRC family for the modulation of transcription in GCT.

Estrogens and epithelial ovarian cancer

OBJECTIVE

Molecular mechanisms involved in ovarian carcinogenesis are still unclear, but there is growing evidence that estrogens promote tumor progression in an epithelial ovarian cancer (EOC) subgroup.

METHODS

We reviewed current knowledge on the effects of estrogens in ovarian carcinogenesis and new potential research focuses concerning hormonal therapy of EOC.

RESULTS

Experimentally, estrogen stimulates the growth of ovarian tumor cell lines expressing estrogen receptors (ER). We and other authors have demonstrated differential expression of ERalpha or beta during ovarian carcinogenesis, with overexpression of ERalpha as compared to ERbeta in cancer. This differential expression in ER suggests that estrogen-induced proteins may act as ovarian tumor-promoting agents. Among these proteins, c-myc, fibulin-1, cathepsin-D, or several kallikreins may play a role, since high expression levels have been found in EOC. Consistently, recent prospective epidemiological studies have indicated that estrogen replacement therapy in postmenopausal women may increase ovarian cancer incidence and mortality.

CONCLUSION

Questions on the estrogen-sensitivity and potential benefits of new hormone therapies in an EOC subgroup should be readdressed in the light of recent experimental and clinical data.

Estrogen and progesterone receptors in ovarian epithelial tumors

Epidemiological studies have indicated a relationship between ovarian cancer and gonadal steroid hormones. In the present study immunohistochemical localization in combination with morphometry were used to characterize changes in the pattern of expression for estrogen receptor alpha (ERalpha), estrogen receptor beta (ERbeta), and progesterone receptor (PR), in epithelial cells of normal ovaries, and in benign, borderline and malignant ovarian tumors of different types (n=53). Positive correlations with immunoreactivity of the cell proliferation-marker, Ki67, and the apoptosis-related marker of genetic instability, p53, between the different tumor types were also found. A simultaneous expression of ERalpha, ERbeta and PR in epithelial cells of all histopathological tumor types was noted, with the notable exception of all mucinous tumors who remained ERbeta-positive, but ERalpha- and PR-negative. Epithelial cells in ovarian cancer tissue showed significantly lower mean immunoreactivity of ERbeta and PR, but not ERalpha, than in normal ovarian tissue. These novel findings may provide a rationale for the development of new diagnostic and possibly therapeutic strategies.

Steroid hormone regulation of the human kallikrein 10 (KLK10) gene in cancer cell lines and functional characterization of the KLK10 gene promoter

BACKGROUND

The human kallikrein 10 (KLK10) gene is a new member of the human tissue kallikrein gene family. It encodes for a secreted serine protease (hK10) with predicted trypsin-like enzymatic activity. KLK10 is highly expressed in the sex organs and its expression level changes in malignancy.

METHODS

To determine the role of steroid hormones in KLK10 gene expression, we investigated its modulation by 17beta-estradiol, 5alpha-dihydrotestosterone, norgestrel, dexamethasone and aldosterone, at both the transcription and translation level, in a panel of cancer cell lines. After steroid hormone stimulation, the change of KLK10 mRNA was monitored with reverse transcriptase polymerase chain reaction and hK10 protein levels in the culture supernatant were quantified with an hK10-specific immunoassay. The presence of hormone response elements in the KLK10 gene promoter was examined with the chloramphenicol acetyltransferase reporter gene system.

RESULTS

The KLK10 expression was mainly up-regulated by estrogens, androgens and progestins, and to a lesser extent by dexamethasone and aldosterone in the breast cancer cell lines BT-474, MCF-7 and T-47D, both at the mRNA and protein levels. The effect of stimulation of these steroids on KLK10 expression varied among the cell lines. Estrogens, androgens and progestins were most potent in the BT-474, T-47D and MCF-7 cells, respectively. The up-regulation effect of estrogens, androgens, and progestins on KLK10 expression can be blocked by their antagonists ICI-182, 780, RU-56,187, and mifepristone, respectively. Time course studies showed that hK10 protein started to increase 1 day after steroid hormone stimulation and this increase persisted for 7 days. These data suggest that steroid hormones up-regulate KLK10 gene expression through direct interaction between hormone-receptor complexes and their cognate hormone response elements. To search for hormone response elements, we functionally characterized the KLK10 promoter by placing it upstream of the chloramphenicol acetyltransferase reporter gene. We found that KLK10 promoter activity did not rely on the presence of functional estrogen and androgen receptors. Also, the presence of functional estrogen and androgen receptors did not increase its constitutive activity. We suggest that the hormone response elements that mediate the transcriptional regulation of KLK10 are unlikely to locate in the KLK10 promoter.

CONCLUSIONS

Estrogens, androgens and progestins modulate KLK10 expression through their own receptors but this regulation is not mediated by steroid hormone response elements in the promoter of the KLK10 gene.

Favorable prognostic value of tissue human kallikrein 11 (hK11) in patients with ovarian carcinoma

Human kallikrein 11 (hK11/trypsin-like serine protease/TLSP, encoded by the KLK11 gene) is a member of the kallikrein family of secreted serine proteases. Recently, we developed a highly sensitive and specific immunoassay for hK11 and found that this protease is expressed in the prostate, stomach and trachea as well as in amniotic fluid and milk of lactating women. Elevated serum hK11 levels were found in 60% of men with prostate cancer and 70% of women with ovarian cancer. Also, hK11 expression was found to be under the regulation of steroid hormones, particularly estrogens, at the level of KLK11 transcription. We hypothesized that hK11 may be implicated in endocrine-related malignancies and serve as a novel prostate and ovarian cancer serological marker. The aim of our study was to examine if hK11 expression in ovarian tumors bears any prognostic significance. The concentration of hK11 (ng per mg of total protein) in 104 ovarian tumor cytosolic extracts was quantified and correlated with clinicopathologic variables and outcome over a median follow-up period of 67 months. Outcome was defined as progression-free survival (PFS) and overall survival (OS). hK11 concentration in ovarian tumor cytosols ranged from 0-21 ng/mg of total protein, with a median of 0.54 ng/mg. An optimal cutoff value of 0.54 ng/mg was selected to categorize tumors as hK11-positive or -negative. hK11-positive tumors were more frequently associated with early stage (Stage I/II) disease, pre-/peri-menopausal status and patients who exhibited complete or partial response to chemotherapy (p < 0.05). Univariate analysis revealed that patients with hK11-positive tumors had a significantly decreased risk of relapse with a hazard ratio (HR) of 0.45 (p = 0.007) and death (HR of 0.34, p = 0.005). Cox multivariate analysis indicated that hK11 was an independent prognostic indicator of OS (HR of 0.41, p = 0.025). Kaplan-Meier survival curves further confirmed that women with hK11-positive tumors have longer PFS and OS (p = 0.005 and p = 0.003, respectively). Similarly, in the subgroup of patients with grade 1-2 tumors, hK11-positivity was associated with higher OS in both univariate and multivariate analysis (HR of 0.23 and 0.17, p < 0.05). Finally, in women with optimal debulking after surgery (<1 cm residual tumor), hK11 positivity was associated with a slower disease progression. These results indicate that hK11 is a novel, independent marker of favorable prognosis in patients with ovarian cancer.

Loss of oestrogen receptor beta, high PCNA and p53 expression and aneuploidy as markers of worse prognosis in ovarian granulosa cell tumours

AIMS

Ovarian granulosa cell tumour (OGCT) is a sex-cord stromal tumour with a general trend toward late relapse and/or metastasis. However, mortality rate corrected for long-term follow-up shows that about 50% of patients die within 20 years of diagnosis. Classical clinicopathological parameters are unable to predict the biological behaviour of OGCT. The involvement of a recently characterized subtype of oestrogen receptor, ERbeta, in ovarian carcinogenesis has been hypothesized.

METHODS AND RESULTS

We examined by immunohistochemistry the expression of ERbeta, proliferating cell nuclear antigen (PCNA) and p53 in a selected series of 30 OGCT, to evaluate their role in the prognostic evaluation of this tumour. Immunohistochemistry was performed on formalin-fixed paraffin-embedded sections. Results were compared with the DNA-ploidy of the tumours (evaluated by image analysis) and with the follow-up data of the patients.

CONCLUSIONS

Loss of ERbeta expression, high PCNA expression and aneuploidy, characterized a subgroup of OGCT with a worse outcome. The identification of a high-risk subclass of OGCT may be of primary importance in addressing appropriate therapeutic strategies, offering the chance to prevent relapses and metastases by using adjunctive, specifically targetted, more aggressive therapies.

Effects of SP500263, a novel selective estrogen receptor modulator, on bone, uterus, and serum cholesterol in the ovariectomized rat

We describe here the activity of a novel selective estrogen receptor modulator, SP500263. When given to adult ovariectomized (OVX) rats for 28 days at doses of 0.3, 1, or 3 mg/kg/day, we found that SP500263 partially protected against OVX-induced loss of bone mineral content in the distal ends of femurs and in the whole bone. SP500263 also antagonized the OVX-induced increase in body weight. However, unlike 17beta-estradiol, SP500263 at efficacious doses did not prevent the OVX-induced loss in uterine wet weight. A small but significant effect on uterine wet weight was noted with raloxifene dosed at 1 mg/kg. As expected, SP500263 but not raloxifene acted as an estrogen antagonist on the uterus in adult rats when administered for 7 days at 30 mg/kg/day. Finally, SP500263 had no statistically significant effects on total serum cholesterol and serum triglycerides in OVX rats treated for 28 days. Raloxifene had no significant effects on body weight, bone mineral content, and serum cholesterol or triglycerides in the OVX-rat model. In summary, SP500263 is a new orally active SERM that acts in rats as an estrogen agonist on bone without causing uterine stimulatory effects.

Early events in ovarian epithelial carcinogenesis: progress and problems in experimental approaches

The etiology and early events in the progression of epithelial ovarian carcinomas are among the least understood of all major human malignancies. There are no adequate means for early detection of these neoplasms and, as a result, they are usually diagnosed in late stages. The purpose of this review is to point out some of the peculiar problems and limitations that have hampered progress in ovarian carcinogenesis research and to summarize new approaches and recent advances in our understanding of this process. The review first presents an overview of the properties of the ovarian surface epithelium (OSE) which is thought to be the source of epithelial ovarian carcinomas, followed by a discussion of recent research based on human OSE. This includes sections on methodology for the attainment and study of OSE, investigations of OSE from women with predisposing mutations, and attempts to convert normal OSE to malignancy. This overview is followed by a discussion of the contributions, potential, and limitations of animal models. The knowledge gained by these approaches will likely lead to improvements in our ability to prevent, diagnose, and treat ovarian cancer.

CYP1A1 gene polymorphism and risk of epithelial ovarian neoplasm

OBJECTIVE

Gene-environment interactions have been the focus of a number of recent studies of the occurrence of human cancers, and an association between the risk and the CYP1A1*3 polymorphism has been noticed for several cancers. Previous studies suggest that estrogens are involved in the etiology of ovarian cancer. The cytochrome P450 1A1 (CYP1A1) gene polymorphism may play role in the development of epithelial ovarian neoplasm by detoxification of polycyclic hydrocarbons and other compounds and the concentration of estrogens and their metabolites. Therefore, we assessed the association of CYP1A1 gene polymorphism in patients with epithelial ovarian neoplasm in the Turkish populations through a case-control study.

METHODS

Using an allele-specific polymerase chain reaction (PCR)-based method, CYP1A1*3 polymorphism, in exon 7 of the gene, was analyzed in 117 epithelial ovarian neoplasm patients and 202 control subjects.

RESULTS

The CYP1A1 Ile/Val genotype significantly increased the risk for patients with epithelial ovarian neoplasm (OR 5.7, 95% CI 3.34-9.76). Furthermore, there were statistical differences in the distribution of CYP1A1 Val/Val genotype among all patients (OR 5.85, 95% CI 2.40-14.25). In other words, the presence of the Val allele significantly increased the risk of epithelial ovarian neoplasm. Among benign tumors, the frequency of Ile/Val and Val/Val genotypes was found to be statistically significant with an ORs of 6.01 and 4.38 (95% CI 2.61-13.84 and 1.04-18.38, respectively). In the benign serous ovarian tumors, patients with Ile/Val and Val/Val revealed a 7.2- and 10.5-fold higher risk of having ovarian carcinoma (95% CI 2.22-23.40 and 2.16-51.19), respectively. In the benign mucinous ovarian carcinoma patients, the frequency of Ile/Val was found to be statistically significant with an OR of 5.15 (95% CI 1.75-15.16). However, no patient with Val/Val genotype was observed in this group and no statistical distribution was performed. Among borderline tumors, CYP1A1 Ile/Val genotype significantly increased the risk for patients (OR 5.15, 95% CI 1.75-15.16). However, only one patient was observed with the Val/Val allele and the frequency of this genotype was not found to be statistically different with an OR of 2.50 (95% CI 0.27-22.64). Among ovarian cancer patients, there were statistically differences in the distribution of CYP1A1 Ile/Val and Val/Val genotypes (OR 5.73, 95% CI 3.04-10.76; and OR 7.42, 95% CI 2.80-19.66), suggesting that patients carrying these genotypes were at increased risk for ovarian carcinoma. In serous carcinoma, patients with CYP1A1 Ile/Val and Val/Val revealed a 6.5- and 10-fold higher risk of having ovarian cancer (OR 7.09, 95% CI 3.30-15.22; and OR 8.77, 95% CI 2.83-27.14). In mucinous carcinoma, patients with CYP1A1 Ile/Val and Val/Val also revealed a 5.4 and 10.5 times higher risk of having ovarian cancer. There were no statistical significance in the distribution of Val allele among endometroid-type cancer patients.

CONCLUSIONS

Our data, although based on a small number of subjects, suggest that variant alleles of CYP1A1 gene in ovarian epithelial cells, directly or through other components, may contribute to initiation of ovarian carcinogenesis.

Hormone replacement therapy formulations and risk of epithelial ovarian carcinoma

OBJECTIVE

Hormone replacement therapy (HRT) has been inconsistently linked to ovarian cancer. Estrogen formulations in HRT vary in their effects on estrogen-sensitive target tissues, such as the ovary. The aim of the study is to evaluate the impact of various HRT formulations and their characteristics of use on the risk of epithelial ovarian carcinoma (EOC).

METHODS

We assessed the association between the use of HRT and the risk of invasive EOC in women participating in a population-based, case-control study conducted in the Delaware Valley from 1994 to 1998. Cases aged 45 or above at diagnosis (n = 484) were compared to community controls (n = 926) frequency matched by age and area of residence. Information on HRT formulation, timing, and duration were obtained by in-person interview by trained interviewers. HRT formulations were classified as opposed (estrogen + progestin) or unopposed (estrogen alone). They were further categorized according to the estrogen component as either conjugated equine estrogen (CEE), the most common formulation, or non-CEE. Multivariate unconditional logistic regression analyses were used to adjust for age at diagnosis, number of live births, use of oral contraceptives, family history of ovarian carcinoma, and history of tubal ligation.

RESULTS

Overall, no association was found between any use of HRT and EOC. Although use of unopposed non-CEE was associated with a significant decrease in risk among hysterectomized women (OR = 0.17, 95% CI = 0.04,0.82), this was not true for women with an intact uterus (OR = 1.14, 95% CI = 0.44,2.98; P for interaction = 0.049). No significant differences in EOC risk were observed for other HRT formulations.

CONCLUSIONS

Our results did not suggest any consistent pattern of altered risk for EOC and the overall use of HRT by specific formulations of HRT.

Differential expression of progesterone receptor isoforms A and B in the normal ovary, and in benign, borderline, and malignant ovarian tumors

Human epithelial ovarian neoplasm is well-known to be sex steroid-related, but the possible biological significance of progesterone actions in these tumors remains controversial. In this study, we examined the differential expression patterns of the two progesterone receptor (PR) isoforms, PRA and PRB, using immunohistochemistry and real-time quantitative RT-PCR in normal and neoplastic ovarian tissues, and in cell lines derived from a normal ovarian surface epithelium and an ovarian epithelial carcinoma in order to further elucidate the possible involvement of progesterone in the development of ovarian neoplasms. The median H scores for PR isoforms in normal (n = 8), benign (n = 10), borderline (n = 8) and malignant (n = 24) ovarian tissues were as follows; PRA: 194.0, 171.0, 49.5, 0 (P < 0.05), and PRB: 175.0, 180.5, 251.5, 168.5, respectively. In ovarian cancer cell lines (OVCAR-3 and Caov-3), the PRB / PRAB mRNA ratio was increased by 17beta-estradiol, both time- and dose-dependently. However, this ratio was unaltered following the addition of 17beta-estradiol in a normal ovarian epithelial cell line (NOV-31). Immunoblotting analysis demonstrated that PRB protein expression was markedly up-regulated in OVCAR-3, whereas the PRA and PRB isoforms both appeared to be increased in NOV-31. These results suggest that down-regulation of PRA is associated with the development of ovarian epithelial carcinoma.

Effects of a lytic peptide conjugated to beta HCG on ovarian cancer: studies in vitro and in vivo

OBJECTIVE

The aim of this study was to determine the in vitro and in vivo effects of the lytic peptide, hecate, alone and conjugated to a 15-amino-acid fragment of the beta-chain of hCG (hecate-beta hCG) on the ovarian carcinoma cell line NIH: OVCAR-3 and determine the expression of luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptors in cell cultures and tumor tissues.

METHODS

For in vitro studies, hecate or hecate-beta hCG was added to cultures of ovarian cancer cells in the presence or absence of estradiol or follicle stimulating hormone. The cytotoxicity of lytic peptides was measured by trypan blue exclusion and lactate dehydrogenase release. For in vivo studies, OVCAR-3 xenografts were established in female athymic nude mice which were then treated once per week for 3 weeks with hecate or hecate-beta hCG via the lateral tail vein. An immunohistochemical method was used to analyze the expression of LH/hCG receptor in tumor and culture cells.

RESULTS

In in vitro studies, both hecate-beta hCG and hecate destroyed ovarian cancer cells (NIH: OVCAR-3) in a dose-dependent manner. Removal of steroids from the culture medium reduced the sensitivity of the OVCAR-3 cell line to the hecate-beta hCG in a reversible manner. In in vivo studies, the average tumor volume and tumor burden in lytic peptide treated animals were reduced. In the groups of animals treated by hecate, hecate-beta hCG, and estradiol + hecate-beta hCG, tumor volumes after treatment expressed as a percentage of increase (197.4 +/- 21.72, 199.0 +/- 18.57, and 193.8 +/- 22.94%, respectively) were reduced, compared to control (263.0 +/- 21.72%) animals (P < 0.05). Immunocytochemical studies revealed the expression of LH/hCG receptor protein in the OVCAR-3 cells and tumor tissues.

CONCLUSION

Hecate-beta hCG is a putative candidate for treating ovarian cancer.

Steroid hormonal regulation of proliferative, p53 tumor suppressor, and apoptotic responses of sheep ovarian surface epithelial cells

Ovarian surface epithelial cells have been implicated in the genesis of common ovarian cancers. The integrity of DNA of ovarian surface epithelial cells contiguous with the ovulatory stigma becomes compromised during the rupture process; most cells degenerate by apoptosis, however some, bearing sublethal lesions, persist along the margins of ovulated follicles. Clonal expansion of a genetically-damaged surface epithelial cell (i.e. with unrepaired DNA, but not committed to death) can presumably give rise to ovarian carcinoma. It was hypothesized that estradiol and progesterone regulate ovarian surface epithelial cell-cycle dynamics associated with folliculo-luteal transitions and ovulatory wound repair/remodeling. Progesterone up-regulated the tumor suppressor p53 and inhibited baseline and estradiol-stimulated proliferation of cultured sheep ovarian surface epithelial cells. Anti/mitotic responses to steroid hormones were transcriptionally- and receptor-dependent. Rates of apoptosis (DNA fragmentation) were unaffected by progesterone. High concentrations of estradiol, via a nongenomic (perhaps antioxidant) mechanism, suppressed basal and H(2)O(2)-induced apoptosis. We suggest that, progesterone serves to inhibit proliferation of ovarian surface epithelial cells throughout the luteal phase--providing the time (growth arrest) required to correct any metabolic disturbances to DNA that are perpetrated as an inevitable by-product of the ovulatory process. With luteolysis and dominance of an estrogenic preovulatory follicle the ovarian surface epithelium is then regenerated. Thus, it is conceivable that perturbations to the steroid hormonal milieu of ovarian cycles could be a predisposing factor for cancerous transformation of an ovarian surface epithelial cell.

High-dose progesterone inhibition of urokinase secretion and invasive activity by SKOV-3 ovarian carcinoma cells: evidence for a receptor-independent nongenomic effect on the plasma membrane

Urokinase plasminogen activator (uPA) has been implicated in the metastatic potential of ovarian carcinomas of surface epithelial origin. The SKOV-3 human ovarian cancer cell line was tested for uPA secretory responses (enzyme immunoassay of conditioned media) after treatments with sex steroids, human menopausal gonadotropins (hMG), or gonadotropin-releasing hormone (GnRH). Secretion of uPA during a 6-h incubation was unaffected by testosterone, estradiol-17beta, hMG, or GnRH. Progesterone, at supraphysiological concentrations, suppressed uPA secretion; this reaction was not altered by the progesterone receptor antagonist RU486 or the transcriptional inhibitor actinomycin D. It appears that progesterone exerted a direct biophysical effect on the plasma membrane manifested by an interference with shedding of uPA in exocytotic vesicles. Finally, invasion of SKOV-3 cells into Matrigel was inhibited by progesterone. We suggest that progesterone can disrupt the fluid dynamics of plasma membranes and thereby invoke an antitumorigenic action via inhibition of proteolytic secretions.

Inhibitory effects of 17beta-estradiol and progesterone on ovarian carcinoma cell proliferation: a potential role for inducible nitric oxide synthase

OBJECTIVES

Indirect evidence suggests that estrogen and progesterone are involved in the etiology of ovarian cancer (Oca). Estrogen and progesterone are also thought to modulate nitric oxide (NO) in human ovarian tumor tissue via regulation of inducible nitric oxide synthase (iNOS). Objectives in this study were: (1) to investigate the effects of 17beta-estradiol (E(2)) and progesterone (P(4)) on Oca cell proliferation employing elevated hormone concentrations occurring within the microenvironment of the ovary, and (2) to determine whether E(2) or P(4) affects iNOS expression and NO generation in Oca cells.

METHODS

Proliferation assays assessed the effects of E(2) and P(4) on cell growth in three human Oca cell lines (HOC-7, OVCAR-3, SKOV-3). Reverse transcriptase polymerase chain reaction was used to assess mRNA expression and Western blots to determine protein levels. NO generation was determined via the Griess reaction.

RESULTS

Elevated E(2), P(4), or E(2) plus P(4) (E + P), significantly inhibited HOC-7 cells and OVCAR-3 cells, but not SKOV-3 cells. E(2) at 10 microM downregulated iNOS expression and significantly reduced NO production in HOC-7 cells, while 10 microM P(4) or 10 microM E + P increased iNOS expression and NO production. Conclusions. Our findings demonstrate that elevated E(2), P(4), or E + P results in significant growth inhibition of Oca cells, and we propose a role for iNOS and NO in how these hormones modulate their activities in Oca cells.

Estradiol up-regulates antiapoptotic Bcl-2 messenger ribonucleic acid and protein in tumorigenic ovarian surface epithelium cells

Most epithelial ovarian tumors appear to arise from the ovarian surface epithelium (OSE). Even though it has been suggested that estrogen may be associated with ovarian tumorigenesis, the exact role of estrogen in the regulation of apoptosis in neoplastic OSE cells remains uncertain. Immortalized OSE (IOSE) cell lines were generated from human normal OSE. These cell lines represent early neoplastic (IOSE-29), tumorigenic (IOSE-29EC), and late neoplastic (IOSE-29EC/T4 and IOSE-29EC/T5) transformation stages from human normal OSE. The present studies demonstrated that both mRNAs and proteins of estrogen receptor (ER) alpha and beta were expressed in IOSE cell lines. No difference was observed in normal OSE and IOSE-29 cells, whereas treatment with 17beta-estradiol (E(2); 10(-8)-10(-6) M) resulted in an increased thymidine incorporation and DNA content per culture in IOSE-29EC cells. This effect of E(2) was attenuated with tamoxifen treatment (10(-6) M), the estrogen antagonist, suggesting that the effect of E(2) is mediated through specific ERs. There was no stimulatory effect on thymidine incorporation before day 6, but after 6 days of E(2) treatment, thymidine incorporation was significantly increased. Because the ratio of thymidine incorporation to DNA content per culture did not change, this E(2) effect does not appear to indicate stimulation of proliferation but, rather, inhibition of apoptosis. In addition, treatment with tamoxifen (10(-6) M) induced apoptosis up to 3-fold in IOSE-29EC cells, whereas cotreatment with E(2) (10(-8)-10(-6) M) plus tamoxifen attenuated tamoxifen-induced apoptosis in a dose-dependent manner. Both proapoptotic bax and antiapoptotic bcl-2 at messenger RNA (mRNA) and protein levels were expressed in IOSE cell lines. Interestingly, treatments with E(2) resulted in a significant increase of bcl-2 mRNA and protein levels (2- and 1.7-fold, respectively), whereas no difference was observed in bax mRNA level. Thus, E(2) may enhance survival of IOSE-29EC by up-regulating bcl-2, and antiapoptotic bcl-2 may be a dominant regulator of apoptotic pathway in these cells. In conclusion, the present study indicates that early neoplastic (IOSE-29), tumorigenic (IOSE-29EC), and late neoplastic (IOSE-29EC/T4 and T5) OSE cells expressed both ERalpha and ERbeta at the mRNA and protein levels. In addition, E(2) prevented tamoxifen induced-apoptosis through ERs. The mechanism of E(2) action may be associated with up-regulation of bcl-2 gene at mRNA and protein levels. These results suggest that estrogen may play a role in ovarian tumorigenesis by preventing apoptosis in tumorigenic OSE cells.

Ovarian surface epithelium: biology, endocrinology, and pathology

The epithelial ovarian carcinomas, which make up more than 85% of human ovarian cancer, arise in the ovarian surface epithelium (OSE). The etiology and early events in the progression of these carcinomas are among the least understood of all major human malignancies because there are no appropriate animal models, and because methods to culture OSE have become available only recently. The objective of this article is to review the cellular and molecular mechanisms that underlie the control of normal and neoplastic OSE cell growth, differentiation, and expression of indicators of neoplastic progression. We begin with a brief discussion of the development of OSE, from embryonic to the adult. The pathological and genetic changes of OSE during neoplastic progression are next summarized. The histological characteristics of OSE cells in culture are also described. Finally, the potential involvement of hormones, growth factors, and cytokines is discussed in terms of their contribution to our understanding of the physiology of normal OSE and ovarian cancer development.

Estrogen receptor isoform gene expression in ovarian stromal and epithelial tumors

The factors involved in the pathogenesis of ovarian cancers remain unclear, and the response of these tumors to hormonal therapy is limited. The identification of a second estrogen receptor gene (ERbeta), expressed predominantly in ovarian granulosa cells, led us to explore its possible role in ovarian cancer, particularly in granulosa cell tumors (GCT). Several isoforms of ERbeta have been identified. We sought to define the patterns of both ERalpha and ERbeta gene expression in a panel of ovarian tumors consisting of GCT and serous and mucinous cystadenocarcinomas as well as in normal ovary. Expression was determined by RT-PCR using gene- and isoform-specific primers and probes combined with Southern blot analysis of the PCR products. Widespread expression of ERalpha was observed in all tumor types, but at relatively low levels. ERbeta is expressed predominantly in GCT, with lower levels in mucinous tumors and very low levels in serous tumors. The ERbeta2 splice variant previously reported in rodents was not observed. Only very low levels of the exon 5, exon 6, and exon 5/6 deletion variants were detected. The C-terminal truncation variant ERbeta(cx), however, exhibited widespread expression across all the tumor types. As ERbeta(cx) has been shown to be a ligand-independent antagonist of ERalpha action, the relative ratios of ERbeta(cx), ERalpha, and ERbeta may influence the response of a tumor to antiestrogen therapy.