The epidemiology of ovarian carcinoma and the current status of tumor markers to detect disease

Synthetic human gonadal tissues for toxicology

The process of mammalian reproduction involves the development of fertile germ cells in the testis and ovary, supported by the surrounders. Fertilization leads to embryo development and ultimately the birth of offspring inheriting parental genome information. Any disruption in this process can result in disorders such as infertility and cancer. Chemical toxicity affecting the reproductive system and embryogenesis can impact birth rates, overall health, and fertility, highlighting the need for animal toxicity studies during drug development. However, the translation of animal data to human health remains challenging due to interspecies differences. In vitro culture systems offer a promising solution to bridge this gap, allowing the study of mammalian cells in an environment that mimics the physiology of the human body. Current advances on in vitro culture systems, such as organoids, enable the development of biomaterials that recapitulate the physiological state of reproductive organs. Application of these technologies to human gonadal cells would provide effective tools for drug screening and toxicity testing, and these models would be a powerful tool to study reproductive biology and pathology. This review focuses on the 2D/3D culture systems of human primary testicular and ovarian cells, highlighting the novel approaches for in vitro study of human reproductive toxicology, specifically in the context of testis and ovary.

Salpingectomy, tubal ligation and hysteroscopic occlusion for sterilization

INTRODUCTION

Sterilization of females is considered one of the most prevalent contraceptive techniques among women in the United States. There are many surgical sterilization procedures including salpingectomy, tubal ligation, and hysteroscopic occlusion of the fallopian tubes. We provide an overview of these methods from the clinical data and latest studies available on this topic.

EVIDENCE ACQUISITION

In order to review the latest literature on the topic, we searched electronic databases including PubMed, Web of Science, Scopus, and Cochrane library for all eligible studies from May 1st 2018 until May 1st 2022 using the following strategy: ("fallopian tube removal" OR Salpingectomy OR "fallopian tube excision" OR "tubal sterilization") AND ("tubal ligation" OR "bipolar coagulation" OR "tubal clip" OR "tubal ring" OR fimbriectomy). We reviewed every study that met our criteria and subjectively considered their results and methodology into this narrative review.

EVIDENCE SYNTHESIS

In addition to reviewing major guidelines in the United States, 19 recent studies met our eligibility criteria and were included in this review. We grouped the findings under the following headings: anatomical and physiological considerations, sterilization, salpingectomy, tubal ligation, and hysteroscopic tubal occlusion.

CONCLUSIONS

Bilateral salpingectomy and techniques of tubal ligation or occlusion continue to be effective procedures with good safety profiles. All techniques have similar surgical outcomes and long-term success rates. As salpingectomy has the advantage of reducing the risk of occurrence of ovarian cancer, this is preferential when feasible. Hysteroscopic occlusion techniques may be more minimally invasive but have the disadvantages of delayed efficacy, the need for a second invasive diagnostic procedure, and limited availability.

[Anatomoclinical study of ovarian cancers in patients with history of hysterectomy for benign pathology]

OBJECTIVE

To establish the various anatomoclinical characteristics of ovarian cancer in patients with a history of hysterectomy for benign disease.

METHODS

This is a comparative, retrospective, monocentric and descriptive study, carried out at the Centre of Jean-Perrin in patients with ovarian cancer between 2005 and 2014 and with a history of hysterectomy for benign disease. Each patient was paired with a non-hysterectomy patient with ovarian cancer. The two populations were matched 1 to 5, based on their age at diagnosis and their FIGO stage.

RESULTS

During the period of the study, 249 patients were operated for de novo ovarian neoplasia, 43 patients had a history of hysterectomy (group 1) and 206 remaining patients represented the control group (group 2). There was no difference in overall survival and disease-free survival between the two subpopulations of patients (P=0.59 and P=0.38). On CT-scan assessment, the lymph node involvement risk was greater than 2.6 in the group of patients with hysterectomy (P=0.00038). Peritoneal Cancer Index scores of the two subgroups of populations were comparable, there were an average of 13.65 for group 1 versus 12.31 for group 2 (P=0.28). The rate of rectosigmoid resection was higher in group 1: 48.6% versus 32.9% in group 2 without any significant difference (P=0.07). Hundred and thirty-three patients undergone lumbar aortic lymphadenectomy, with node involvement found in 83% of patients in the hysterectomy group and 51% of patients in the control group (P=0.0053).

CONCLUSION

Indication of lumbar aortic lymphadenectomy should be taken in better consideration in patients with history of inter-adnexial hysterectomy. These data must be thoroughly assessed with a prospective multicenter comparative study.

Correlation of HLA-A02* genotype and HLA class I antigen down-regulation with the prognosis of epithelial ovarian cancer

BACKGROUND

In recent years, evidence is accumulating that cancer cells develop strategies to escape immune recognition. HLA class I HC down-regulation is one of the most investigated. In addition, different HLA haplotypes are known to correlate to both risk of acquiring diseases and also prognosis in survival of disease or cancer. We have previously shown that patients with serous adenocarcinoma of the ovary in advanced surgical stage disease have a particularly poor prognosis if they carry the HLA-A02* genotype. We aimed to study the relationship between HLA-A02* genotype in these patients and the subsequent HLA class I HC protein product defects in the tumour tissue.

MATERIALS AND METHODS

One hundred and sixty-two paraffin-embedded tumour lesions obtained from Swedish women with epithelial ovarian cancer were stained with HLA class I heavy chain (HC) and β(2)-microglobulin (β(2)-m)-specific monoclonal antibodies (mAb). Healthy ovary and tonsil tissue served as a control. The HLA genotype of these patients was determined by PCR/sequence-specific primer method. The probability of survival was calculated using the Kaplan-Meier method, and the hazard ratio (HR) was estimated using proportional hazard regression.

RESULTS

Immunohistochemical staining of ovarian cancer lesions with mAb showed a significantly higher frequency of HLA class I HC and β(2)-m down-regulation in patients with worse prognosis (WP) than in those with better prognosis. In univariate analysis, both HLA class I HC down-regulation in ovarian cancer lesions and WP were associated with poor survival. In multivariate Cox-analysis, the WP group (all with an HLA-A02* genotype) had a significant higher HR to HLA class I HC down-regulation.

CONCLUSIONS

HLA-A02* is a valuable prognostic biomarker in epithelial ovarian cancer. HLA class I HC loss and/or down-regulation was significantly more frequent in tumour tissues from HLA-A02* positive patients with serous adenocarcinoma surgical stage III-IV. In multivariate analysis, we show that the prognostic impact is reasonably correlated to the HLA genetic rather than to the expression of its protein products.

Immunohistochemical and ultrastructural characterization of the ovarian surface epithelium of Japanese quail (Coturnix japonica)

Contrary to humans, most ovarian tumors in other species do not arise from the ovarian surface epithelium but are of follicular-, stromal- or germ-cell origin. One of the few species where ovarian cancer arises from the ovarian surface epithelium (OSE) is chicken (Gallus domesticus). Little is known about the morphology of the OSE in other avian species. In our study we analyzed the OSE morphology of Japanese quail (Coturnix japonica) using ultrastructural and histochemical techniques. Carbohydrate residues have been studied by using a panel of fluorescein isothiocyanate labeled lectins. Japanese quails are commonly used animal models in biomedical research as their housing is comparatively inexpensive and they show a short generation interval. Our ultrastructural and histochemical results demonstrate that the quail ovarian surface epithelium shows characteristic features which resemble the epithelia of both chicken and human. Additionally, the ovarian surface epithelium of the Japanese quail contains cytokeratin as well as vimentin intermediate filaments in their cytoplasm. Therewith and among other parts the quail OSE shows many characteristic features also seen in those of humans, which may qualify quail's ovary as a potential animal model for human ovarian carcinomas.

Conditional knockout of brca1/2 and p53 in mouse ovarian surface epithelium: do they play a role in ovarian carcinogenesis?

Alterations of genes are known to be critical for the induction of tumorigenesis, but the mechanism of ovarian carcinogenesis is little understood and remains to be elucidated. In this study, we investigated the roles of brca1, brca2 and p53 genes in the development of ovarian cancer using conditional knockout mice generated by a Cre-loxP recombinant system. Following the application of recombinant adenovirus expressing Cre in vitro, the proliferation of ovarian surface epithelium (OSE) was increased. For instance, a significant increase in cell growth was observed in OSE cells in vitro by conditional knockout isolated from the mice bearing concurrent floxed copies of brca1 and brca2/p53. However, the proliferative effect of the ovarian cells was not observed in concurrent brca1/brca2 or p53 knockout mice in vivo, indicating that we could not observe the direct evidence of the involvement of brca1, brca2, and p53 in ovarian carcinogenesis. Since morphological changes including tumor formation were not observed in mice bearing floxed copies of concurrent brca1/brca2 or p53, the inactivation of brca1/2 or p53 is not sufficient for the induction of tumor formation. Taken together, these results suggest that the deficiency of these genes may not be involved directly in the mechanism of ovarian carcinogenesis.

Ovarian cancer plasticity and epigenomics in the acquisition of a stem-like phenotype

Aggressive epithelial ovarian cancer (EOC) is genetically and epigenetically distinct from normal ovarian surface epithelial cells (OSE) and early neoplasia. Co-expression of epithelial and mesenchymal markers in EOC suggests an involvement of epithelial-mesenchymal transition (EMT) in cancer initiation and progression. This phenomenon is often associated with acquisition of a stem cell-like phenotype and chemoresistance that correlate with the specific gene expression patterns accompanying transformation, revealing a plasticity of the ovarian cancer cell genome during disease progression.Differential gene expressions between normal and transformed cells reflect the varying mechanisms of regulation including genetic changes like rearrangements within the genome, as well as epigenetic changes such as global genomic hypomethylation with localized promoter CpG island hypermethylation. The similarity of gene expression between ovarian cancer cells and the stem-like ovarian cancer initiating cells (OCIC) are surprisingly also correlated with epigenetic mechanisms of gene regulation in normal stem cells. Both normal and cancer stem cells maintain genetic flexibility by co-placement of activating and/or repressive epigenetic modifications on histone H3. The co-occupancy of such opposing histone marks is believed to maintain gene flexibility and such bivalent histones have been described as being poised for transcriptional activation or epigenetic silencing. The involvement of both-microRNA (miRNA) mediated epigenetic regulation, as well as epigenetic-induced changes in miRNA expression further highlight an additional complexity in cancer stem cell epigenomics.Recent advances in array-based whole-genome/epigenome analyses will continue to further unravel the genomes and epigenomes of cancer and cancer stem cells. In order to illuminate phenotypic signatures that delineate ovarian cancer from their associated cancer stem cells, a priority must lie in the expansion of current technologies and further implementation of bioinformatics to handle the complexity of the cancer epigenome and the various networks that coordinate disease initiation and progression. Great potential lies in the translation of these findings into epigenetic-based therapies. Additionally, targeting chemo-resistant cancer stem cells may provide a much needed breakthrough in treatment of advanced ovarian cancer and chemoresistant disease.

cAMP response element-binding protein is expressed at high levels in human ovarian adenocarcinoma and regulates ovarian tumor cell proliferation

Approximately 90% of human ovarian tumors result from transformation of ovarian surface epithelial cells. It has been hypothesized that repeated destruction of the epithelial cells during ovulation, followed by proliferation and migration of epithelial cells to restore the ovarian surface, renders these cells susceptible to mutagenic events. One of the proteins found to promote ovarian surface epithelial cell survival and proliferation was the transcription factor, cAMP response element-binding protein (CREB). Thus, the objective of this study was to determine whether CREB was also highly expressed in tumor cells originating from the ovarian epithelium. Using an ovarian cancer tissue array, it was observed that approximately 54% of the epithelial-derived human ovarian tumors displayed moderate or high levels of CREB immunostaining, while none of the normal ovarian samples did. Comparison of CREB levels in a human ovarian tumor cell line to those of a normal ovarian epithelial cell line revealed elevated levels of CREB and phosphorylated CREB in the ovarian tumor cells. To determine whether CREB regulated proliferation and/or apoptosis in the ovarian tumor cell line, CREB expression was suppressed using RNA interference. Decreased CREB expression significantly reduced ovarian tumor cell proliferation, while there was no effect on apoptosis in these cells. Finally, we showed that CREB is highly expressed in an in vivo murine model of ovarian tumorigenesis. Therefore, CREB is frequently overexpressed in ovarian cancer where it appears to promote cell proliferation.

Gonadotropins and ovarian cancer

Ovarian epithelial cancer (OEC) accounts for 90% of all ovarian cancers and is the leading cause of death from gynecological cancers in North America and Europe. Despite its clinical significance, the factors that regulate the development and progression of ovarian cancer are among the least understood of all major human malignancies. The two gonadotropins, FSH and LH, are key regulators of ovarian cell functions, and the potential role of gonadotropins in the pathogenesis of ovarian cancer is suggested. Ovarian carcinomas have been found to express specific receptors for gonadotropins. The presence of gonadotropins in ovarian tumor fluid suggests the importance of these factors in the transformation and progression of ovarian cancers as well as being prognostic indicators. Functionally, there is evidence showing a direct action of gonadotropins on ovarian tumor cell growth. This review summarizes the key findings and recent advances in our understanding of these peptide hormones in ovarian cancer development and progression and their role in potential future cancer therapy. We will first discuss the supporting evidence and controversies in the "gonadotropin theory" and the use of animal models for exploring the involvement of gonadotropins in the etiology of ovarian cancer. The role of gonadotropins in regulating the proliferation, survival, and metastasis of OEC is next summarized. Relevant data from ovarian surface epithelium, which is widely believed to be the precursor of OEC, are also described. Finally, we will discuss the clinical applications of gonadotropins in ovarian cancer and the recent progress in drug development.

Neuropilin-1 promotes unlimited growth of ovarian cancer by evading contact inhibition

OBJECTIVE

Neuropilin-1 (NRP-1) is a receptor for both semaphorin and vascular endothelial growth factor and is up-regulated in a variety of human cancers. While there are some reports of NRP-1 expression in ovarian neoplasm, those results differ in pattern of its expression and its role in ovarian cancer is still unclear. We sought to investigate the expression pattern and role of NRP-1 in ovarian cancer.

METHODS

NRP-1 expression was analyzed with eighty-seven ovarian tissue samples by immunohistochemistry and four ovarian cell lines by quantitative RT-PCR and Western blotting. To detect its molecular role in ovarian cancer, WST-1 assay, invasion assay and soft agar assay were performed with or without NRP-1 suppression by the introduction of short hairpin RNAs.

RESULTS

NRP-1 expression was found to be enhanced in ovarian cancer compared with ovarian surface epithelium (OSE), benign adenoma and tumors of low malignant potential. In vitro, NRP-1 expression was augmented threefold during malignant transformation of OSE cells with oncogene ras, suggesting an association between NRP-1 and oncogenesis. Suppression of NRP-1 reduced cell proliferation in a dense state, indicating that persistently high expression of NRP-1 in ovarian cancer enhances proliferation through evasion of contact inhibition. Suppression of NRP-1 also decreased cell growth in soft agar and invasion to the extracellular matrix in vitro.

CONCLUSIONS

These results suggest that NRP-1 is not only associated with oncogenesis, but also with ovarian cancer malignancy, and this molecule is a targeting candidate for the treatment of ovarian malignancies.

Multiple biomarker panels for early detection of ovarian cancer

Ovarian cancer is the eighth most common cause of cancer mortality in women. It is diagnosed in more than 20,000 women in the USA each year and approximately 15,000 women die of the disease annually. The majority of patients are diagnosed with advanced-stage ovarian cancer, as this deadly disease causes minimal and nonspecific symptoms until late in the course of the disease. No standardized screening test exists to reliably detect ovarian cancer. Cancer antigen (CA)-125 is a protein antigen found at abnormally high levels in the blood of many women with ovarian cancer. Most healthy women have CA-125 levels of below 35 units/microl of blood serum. However, a number of noncancerous conditions can cause elevated CA 125 levels, and many women with early-stage ovarian cancer have normal CA-125 levels. Owing to these limitations, this test is not recommended for routine screening in women who are not at high risk or who do not have specific symptoms of the disease. Currently, many researchers are focusing on simultaneous examination of multiple markers to increase sensitivity of the screening test for early detection of ovarian cancer. Analysis of the current literature shows that combining several biomarkers dramatically improves sensitivity of CA-125 in ovarian cancer patients. This article provides a comprehensive overview of existing studies in the area of multimarker panel development for the early detection and monitoring of ovarian cancer. Our literature review demonstrates that a multimarker approach for the generation of a prototype assay for early detection of ovarian cancer has a great potential to lead to the development of a screening test for this disease.

Expression analysis and prognostic significance of the SRA1 gene, in ovarian cancer

The SR-related-CTD-associated-factors (SCAFs) have the ability to interact with the C-terminal domain of the RNA polymerase II, linking this way transcription to splicing. SRA1 (SR-A1) gene, encoding for a human high-molecular weight SCAF protein, is located on chromosome 19, between the IRF3 and the R-RAS oncogene and it has been demonstrated from members of our group that SRA1 is constitutively expressed in most of the human tissues, while it is overexpressed in a subset of ovarian tumors. In this study, we examine the expression of SRA1 gene in 111 ovarian malignant tissues and in the human ovarian carcinoma cell lines OVCAR-3, TOV21-G, and ES-2, using a semi-quantitative RT-PCR method. SRA1 gene was overexpressed in 61/111 (55%) of ovarian carcinomas. This higher expression was positively associated to the size of the tumor (p<0.001), the grade and the stage of the disease (p=0.003 and p=0.006, respectively), and the debulking success (p<0.001). Kaplan-Meier survival analysis revealed that lower SRA1 expression increases the probability of both the longer overall and the progression free survival of the patients. Multivariate Cox regression analysis revealed that SRA1 may be used as an independent prognostic biomarker in ovarian cancer. Our results suggest that SRA1 is associated with cancer progression and may possibly be characterized as a new marker of unfavorable prognosis for ovarian cancer.

Prediction of Extravesical Disease by Preoperative Serum Markers in Patients With Clinically Organ Confined Invasive Bladder Cancer

PURPOSE

We assessed the value of preoperative levels of CEA, CA-125 or CA 19-9 in patients with clinically organ confined bladder cancer to predict pathological extravesical and/or node positive disease.

MATERIALS AND METHODS

Serum levels of CEA, CA-125 and CA 19-9 were measured prospectively in all patients scheduled for cystectomy for clinically organ confined bladder cancer between September 1999 and May 2004. Biomarker expression was compared between patients with pathologically organ confined disease (pT2 or less, pN0) and patients with extravesical disease (greater than pT2, or pN1 or greater), and between patients with pathologically node negative (any pT, pN0) and node positive disease (any pT, pN1 or greater).

RESULTS

Of the 91 patients enrolled, 46 had (51%) pathologically organ confined tumors, 45 (49%) had extravesical disease and 17 (19%) had positive lymph nodes. Preoperative serum levels of all markers were significantly higher in cases of extravesical disease than in organ confined disease. On multivariate analysis CEA with an odds ratio of 8.6 (95% CI 1.51-48.6) and CA-125 with an OR of 29.5 (95% CI 3.6-242.6) proved independent predictors of extravesical disease. CA-125 and CA 19-9 levels were significantly higher in patients with node positive disease than in those with node negative disease. On multivariate analysis CA-125 with an OR of 22.2 (95% CI 3.8-129) and CA 19-9 with an OR of 5.2 (95% CI 1.09-24.76) proved independent predictors of node positive disease.

CONCLUSIONS

Increase in serum tumor markers before cystectomy in patients with clinically organ confined muscle invasive bladder cancer is a strong indicator of the presence of extravesical and node positive disease.

USEFULNESS OF CA 125 AS A PREOPERATIVE PROGNOSTIC MARKER FOR TRANSITIONAL CELL CARCINOMA OF THE BLADDER

PURPOSE

We evaluated the role of CA 125 as a prognostic marker in patients with transitional cell carcinoma (TCC) of the bladder undergoing uniform radical cystectomy with bilateral pelvic iliac lymphadenectomy.

MATERIALS AND METHODS

From April 1996 to March 2001, 287 patients with a median age of 68 years (range 34 to 89) had preoperative CA 125 serum assays performed. All patients had high grade or invasive TCC and were scheduled to undergo radical cystectomy. Preoperative CA 125 was evaluated according to tumor grade and pathological subgroups (organ confined, extravesical and lymph node positive) as well as recurrence-free and overall survival.

RESULTS

Of the 287 patients 31 (10.8%) demonstrated increased serum CA 125 (greater than 35 U/ml). No significant association was found between increased CA 125 and recurrence-free survival or tumor grade. However, a statistically significant association was found among pathological tumor subgroups, namely 4.9% for organ confined, 11.3% for extravesical and 21.6% for lymph node positive disease (p <0.001). Furthermore, patients with lymph node positive disease or high grade tumors (grades III/IV and IV/IV) and increased CA 125 assays demonstrated significantly worse overall survival (p <0.001).

CONCLUSIONS

Increased CA 125 was seen in approximately 11% of patients with high grade or invasive TCC preoperatively. It was more commonly found in patients with locally advanced and lymph node positive disease, and it was associated with overall survival. However, recurrence-free survival was not associated with CA 125. Further studies are required to define the exact role of CA 125 in bladder cancer.

Alternative Splicing of theMultidrug Resistance Protein 1/ATP Binding Cassette Transporter SubfamilyGene in Ovarian Cancer Creates Functional Splice Variants and Is Associated with Increased Expression of the Splicing Factors PTB and SRp20

PURPOSE

Overexpression of multidrug resistance protein 1 (MRP1) confers resistance to a range of chemotherapeutic agents in cell lines and could be involved in clinical drug resistance of some tumor types also. We examined MRP1 expression in a small series of untreated human ovarian tumors and matched normal tissues.

EXPERIMENTAL DESIGN

We analyzed ten pairs of snap-frozen ovarian tumor and matched normal total ovarian tissues from the same patients for expression of MRP1 by reverse transcription-PCR. Amplified PCR products were sequenced to reveal splicing events of MRP1. MRP1 splice variants were expressed as enhanced green fluorescent fusion proteins in HEK293T cells to demonstrate their localization in the cell and their activity in conferring resistance to doxorubicin. The expression of splicing factors PTB and SRp20 was examined by Western blot.

RESULTS

MRP1 was expressed in all 10 of the pairs of specimens. Multiple MRP1 cDNA fragments of various sizes were amplified between exons 10 and 19. Of interest, more MRP1 cDNA fragments were detected in ovarian tumors than in matched normal tissues in 9 of 10 pairs. We identified 10 splicing forms between exons 10 and 19 of the MRP1 gene with exon skipping ranging from 1 to 7. Amplification of the entire coding region of MRP1 from 1 ovarian tumor revealed >20 splice variants. We found whole and partial exon skipping and partial intron inclusion in these splice variants. We expressed 3 of these MRP1 splice variants in HEK293T cells and found that they appeared to localize to the plasma membrane and were functional in conferring resistance to doxorubicin. In addition, we identified a few nucleotide variations in this gene. To understand the basis for increased splice variants in the tumors, we examined splicing factor expression in these tissues. Western blot analysis revealed that two splicing factors, PTB and SRp20, were overexpressed in most ovarian tumors compared with their matched normal ovarian tissues. Importantly, overexpression of both of these splicing factors was associated with the increased number of MRP1 splicing forms in the ovarian tissues.

CONCLUSION

The MRP1 gene undergoes alternative splicing at a higher frequency in ovarian tumors than in matched normal tissues. Some of these splice variants confer resistance to doxorubicin. Expression of splicing factors PTB and SRp20 is strongly associated with the alternative splicing of the MRP1 gene.

Type II gonadotropin-releasing hormone stimulates p38 mitogen-activated protein kinase and apoptosis in ovarian cancer cells

Recent results indicate that a novel second form of GnRH, GnRH-II, has an antiproliferative effect on ovarian and endometrial cancer cells and might be considered as a possible therapy for gynecological tumors. However, the mechanism of the GnRH-II-induced antiproliferative effect is not known. The p38 MAPK, one of the stress-activated protein kinases, is activated by diverse cellular stress and proinflammatory cytokines. In this study, the effect of GnRH-II on the activation of p38 MAPK was investigated, and its possible role in the regulation of cell proliferation and apoptosis was further examined in the human ovarian cancer cell line, OVCAR-3. Treatment with GnRH-II (100 nM) resulted in an activation of p38 MAPK in a time-dependent manner. A significant activation of p38 MAPK was observed at 2, 5, 10, and 15 min after GnRH-II treatment. The activation of p38 MAPK by GnRH-II was reversed in the presence of a specific inhibitor of p38 MAPK, SB203580 (1 microM). The transcription factor, activator protein-1, was activated (1.5-fold) by GnRH-II and attenuated in the presence of SB203580 (1 microM). Treatment with GnRH-II (1 nM, 100 nM, 10 microM) for 2, 4, and 6 d resulted in an inhibition of cell growth in OVCAR-3 cells as determined by thymidine incorporation assay. The effect of GnRH-II (100 nM) on cell proliferation was blocked by pretreatment with SB203580 (1 microM). Furthermore, a significant increase of apoptosis (1.6-fold) was observed after GnRH-II treatment, which was also reversed by pretreatment with SB203580 (1 microM). Taken together, these results indicate that p38 MAPK is involved in the GnRH-II-induced inhibition of cell growth through activator protein-1 activation, which may be related to induction of apoptosis in ovarian cancer cells.

A novel immunohistochemical method for estimating cell cycle phase distribution in ovarian serous neoplasms: implications for the histopathological assessment of paraffin-embedded specimens

We have investigated whether immunohistochemical markers can identify differences in cell cycle phase distribution in ovarian serous neoplasms, including borderline tumours of different grades. Sections of normal ovary (n=18), serous cystadenoma (n=21), borderline serous tumours (n=21) and serous cystadenocarcinoma (n=15) were analysed by immunohistochemistry using markers of cell cycle entry (Mcm-2) and cell cycle phase, including cyclin D1 (mid-to-late G1), cyclin A (S phase), cyclin B1 (G2 phase) and phosphohistone H3 (mitosis). Double-labelling confocal microscopy confirmed marker phase specificity and phase estimations were corroborated by flow cytometry. On progression from normal ovary through serous cystadenoma and borderline tumours to cystadenocarcinomas, expression of Mcm-2 (P<0.0001), cyclin D1 (P=0.002), cyclin A (P<0.0001), cyclin B1 (P<0.0001) and phosphohistone H3 (P<0.0001) increased, paralleled by an increase in the S-phase fraction (cyclin A : Mcm-2 ratio; P=0.002). Borderline tumours of increasing grade also showed increased Mcm-2 and cyclin A expression, together with an increase in the S-phase fraction. Immunohistochemistry can be used to estimate cell cycle phase distribution in ovarian serous neoplasms, giving results similar to flow cytometric analysis and enabling direct assessment of tumour heterogeneity. Immunohistochemical estimates of the S-phase fraction may identify serous borderline tumours likely to exhibit malignant progression and/or select serous cystadenocarcinomas likely to respond to adjuvant therapy.

C-erbB-2 or mutant Ha-ras induced malignant transformation of immortalized human ovarian surface epithelial cells in vitro

Ovarian cancer is believed to develop from the ovarian surface epithelium through the accumulation of aberrations of oncogenes and/or tumor suppressor genes. However, it is unclear how the gene abnormalities are involved in ovarian carcinogenesis. To elucidate the process, we transfected genes reported to show their abnormalities in human ovarian cancers into human ovarian surface epithelial cells. Immortalization of the cells was achieved by the transfection of SV40 large T antigen (LT) and human telomerase reverse transcriptase (hTERT); however, the resultant cells showed no tumorigenesis. Additional transfection of either c-erbB-2 or mutant Ha-ras into the immortalized cells showed the anchorage-independent growth and tumorigenesis in mice with the incidence of 50% and 40%, respectively. Histologically, all the tumours were undifferentiated. In association with the tumorigenesis, the cells expressing c-erbB-2 or mutant Ha-ras demonstrated increased vascular endothelial growth factor secretion under hypoxia and enhanced resistance to apoptosis compared with the immortalized cells. Collectively, the introduction of either c-erbB-2 or mutant Ha-ras in the cells, which were efficiently immortalized by the transfection of LT and hTERT, showed tumorigenicity, suggesting that c-erbB-2 or mutant Ha-ras genes might be involved in ovarian carcinogenesis.

Genetic and cytogenetic observations among different types of ovarian tumors are compatible with a progression model underlying ovarian tumorigenesis

In this report we present the characterization of ovarian neoplasms including benign tumors, borderline tumors, and invasive carcinomas in order to assess whether a sharing of cytogenetic abnormalities is present in all three types of tumors. A cohort of 114 newly diagnosed and untreated ovarian epithelial tumors were analyzed by cytogenetic and molecular cytogenetic approaches with probes specific for chromosome 6. Three groups of chromosome abnormalities were identified: the first group included abnormalities common to all tumor classes (losses of chromosomes 6, 8, 10, 11, 15, 16, 17, 18, 19, 20, 21, 22, and X; gains of chromosomes 1, 3, 5, and 12; 6q24 approximately qter deletions); the second group presented specific abnormalities present in malignant but not in benign tumors (losses of chromosomes 2, 7, 13, and 14; gains of chromosome 4 and chromosome markers); and the last group included abnormalities unique to invasive carcinomas (loss of chromosome 4; gains of chromosomes 2, 7, 8, 9, 10, 16, 17, 18, 19, 20, and 21; 6q16 approximately q24 deletions; rearrangements of 3p, 3q, 13q, and 21q regions). The presence of shared chromosomal alterations in all three types of ovarian neoplasms investigated in this report seems therefore to suggest a progression model for these types of tumors.

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.

Developing a cancer genetics service in Wales: opinions of gynaecologists on the management of women at risk of familial ovarian cancer

In Wales, a cancer genetics service has been developing since 1998. Gynaecologists play an integral role in the management of women with a family history of ovarian cancer and we were interested in investigating referral practice and management for relatives of patients with ovarian cancer among gynaecologists in Wales. In 1999, a postal questionnaire was sent to all gynaecologists. The response rate was 51%. The questionnaire contained structured questions about current provision and a number of hypothetical scenarios to explore referral patterns to the cancer genetics service. The results of this study showed that referrals varied widely among specialists, as did the numbers who required onward referral to cancer genetics. The offer of screening to women at high risk of ovarian cancer was consistent, although there were variations in how often it was offered and the age at which it was offered. Most gynaecologists were easily able to establish when it was appropriate to refer onwards to cancer genetics, differentiating between women at high or low risk. There was some confusion about women at moderate risk of ovarian cancer. This study demonstrated the need for clear referral guidelines in Wales. Guidelines have since been distributed to all general practitioners and specialists; however, continued monitoring and further evaluation of referral practices will be necessary.

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.

Epidemiologic differences between women with colorectal cancer and women with ovarian cancer

BACKGROUND AND OBJECTIVES

The difference between the epidemiologic features of women with colorectal cancer and those with ovarian cancer has not been thoroughly studied. The aim of this study is to review the epidemiologic features of women with colorectal cancer and compare them with those of women with ovarian cancer.

METHODS

The epidemiologic features of 705 women with colorectal cancer were compared with those of 503 women with primary epithelial ovarian cancer. Both groups included all women with the confirmed respective histologic diagnoses admitted to Roswell Park Cancer Institute between 1982 and 1996 who returned a voluntary self-administered epidemiologic questionnaire.

RESULTS

Women with ovarian cancer were significantly younger, had higher education and income, had fewer children, and were more likely to have never been married and nulligravid than those with colorectal cancer. There was a significant difference in the contraceptive history between both groups among women > or = 45 years of age. More women with ovarian cancer had a family history of ovarian cancer and more women with colorectal cancer had a family history of colorectal cancer.

CONCLUSIONS

The epidemiologic features of women with colorectal cancer are different from those with ovarian cancer. The difference between both groups might indicate difference in the environmental or genetic etiology of both cancers.

Perineal talc exposure and risk of ovarian carcinoma

BACKGROUND

Clinical and epidemiologic studies have indicated the possible existence of an association between ovarian carcinoma and talcum powder use. Talc particles have been detected in histologic sections of ovarian carcinomas. It has also been demonstrated that inert particles travel from the perineum to the ovaries. Results from epidemiologic investigations have varied, from risks increased by twofold to no significant risk detected.

METHODS

A total of 450 patients with borderline and invasive ovarian carcinoma and 564 population controls in metropolitan Toronto and nearby areas of southern Ontario, Canada, were identified. These subjects were interviewed about their reproductive and menstrual histories as well as their exposure to dusting powders. Continuous unconditional logistic regression methods were used for analysis.

RESULTS

Exposure to talc, via sanitary napkins, direct application to the perineum, or both, was significantly associated with risk of ovarian carcinoma (odds ratio [OR] 1.42, 95% confidence interval [CI] 1.08-1.86). A borderline-significant association was detected between duration of talc exposure and risk (OR 1.09, 95% CI 0.98-1.21, per 10 years of exposure). No significant association was found between frequency of exposure and risk. In comparing invasive and borderline carcinomas, risk remained elevated for both carcinoma types. Only risk for invasive carcinoma was statistically significant.

CONCLUSIONS

This investigation supports previous contentions that exposure to talc may increase risk of ovarian carcinoma. Questionable trends in duration and frequency of exposure suggest that further studies may be needed to clarify the role of talc in the etiology of this disease.

Screening for ovarian cancer

Ovarian cancer is the leading cause of death from gynecologic cancer. Despite aggressive cytoreductive surgery and platinum-based chemotherapy, the 5-year survival for patients with clinically advanced ovarian cancer is only 15 to 20 percent, although the cure rate for stage I disease is usually greater than 90 percent. These statistics provide the primary rationale for ovarian cancer screening. This overview of the current literature serves to show that mass screening for ovarian cancer is far from being established and fraught with management and procedural dilemmas. The reasonable assumption being that there is little evidence to support widespread screening of large populations of women who do not have familial or genetic risk factors for ovarian cancer.

Calcified brain metastases from ovarian carcinoma

A case of calcified brain metastases from ovarian carcinoma is reported. Lesions developing during chemotherapy were thought on Ct to be parasitic and, to avoid dissemination of pathogens, biopsy was postponed. When neurological deficits progressed, MRI showed perifocal oedema and contrast enhancement. It also showed a new noncalcified focus which was biopsied, proving to be a metastasis.

Screening for Ovarian Cancer

Ovarian cancer is difficult to manage because the disease is most often diagnosed at an advanced stage when survival chances are poor. Early detection of ovarian cancer would increase long-term survival, since effective treatment modalities are available for early-onset disease. Screening with transvaginal ultrasound and serum CA 125 suggests promising results, but studies comparing mortality rates for screened vs unscreened populations are needed, and strategies must be developed for prevention or early diagnosis in order to control this disease process.

Malignant ascites

Investigation and treatment of malignant ascites are often in the hands of the general surgeon and can be difficult. This article considers the aetiology and pathophysiology of malignant ascites and explores the best form of management. Established treatment modalities and new therapeutic options are reviewed and a new management regimen based on a knowledge of the tumour of origin is proposed, which aims to balance potential benefit against morbidity.

Early detection of ovarian carcinoma with transvaginal color Doppler ultrasonography

OBJECTIVE

Our purpose was to assess the potentials and limitations of the early detection of ovarian cancer in protocols that involve transvaginal color Doppler ultrasonography.

STUDY DESIGN

Retrospective analysis was performed on the data from 206 referred patients who either had surgical or clinical follow-up of ovarian masses evaluated by transvaginal color Doppler ultrasonography. Most of the patients were referrals or had risk factors.

RESULTS

In this series of 206 patients, 26 ovarian cancers were detected, > 70% of which were stage I or II.

CONCLUSION

Transvaginal color Doppler ultrasonography is capable of early detection of ovarian carcinoma. An improved detection rate may be realized with better identification of high-risk patients who should be studied with transvaginal color Doppler ultrasonography.