Early detection of ovarian cancer: background, rationale, and structure of the Yale Early Detection Program.

Ovarian cancer has received national attention as a highly virulent disease. Its lack of early warning symptoms and the failure to develop highly sensitive screening tests have led some physicians to recommend prophylactic oophorectomies to women with relatives who have had ovarian cancer. Others have recommended routine screening of otherwise normal women for CA 125, a circulating tumor marker, and ultrasound examinations. Each of these techniques is associated with substantial false-positive rates that could lead to unnecessary surgery. A review of epidemiologic data suggests that familial ovarian cancer kindreds are rare, but women with first-degree relatives who have had ovarian cancer have a significant risk themselves for developing ovarian cancer. In addition, women with a great number of ovulatory cycles are at an increased risk for the disease. Circulating tumor markers are frequently elevated in women with advanced ovarian cancer, but their value in early detection of ovarian cancer has yet to be established. Advances in endovaginal ultrasound and color Doppler flow technology have significantly improved our ability to assess pelvic organs. This article presents the background, rationale, and structure of the Yale Early Detection Program for ovarian cancer, whose goals are to identify the best techniques for diagnosing ovarian cancer in an early stage, to determine the frequency with which such tests should be employed, to assess false-positive results, and to identify women who might benefit from prophylactic oophorectomies.     

Premature ovarian failure

The diagnosis of premature ovarian failure is based on the finding of amenorrhoea before age 40 associated with follicle-stimulating hormone levels in the menopausal range. Screening for associated autoimmune disorders and karyotyping, particularly in early onset disease, constitute part of the diagnostic work up. There is no role for ovarian biopsy or ultrasound in making the diagnosis. Management essentially involves hormone replacement and infertility treatment, the most successful being assisted conception with donated oocytes. Embryo cryopreservation, ovarian tissue or oocyte cryopreservation and in vitro maturation of oocytes hold promise in cases where ovarian failure is foreseeable as in women undergoing cancer treatments.     

Blood Cell Mitochondrial DNA Content and Premature Ovarian Aging

Primary ovarian insufficiency (POI) is a critical fertility defect characterized by an anticipated and silent impairment of the follicular reserve, but its pathogenesis is largely unexplained. The frequent maternal inheritance of POI together with a remarkable dependence of ovarian folliculogenesis upon mitochondrial biogenesis and bioenergetics suggested the possible involvement of a generalized mitochondrial defect. Here, we verified the existence of a significant correlation between blood and ovarian mitochondrial DNA (mtDNA) content in a group of women undergoing ovarian hyperstimulation (OH), and then aimed to verify whether mtDNA content was significantly altered in the blood cells of POI women. We recruited 101 women with an impaired ovarian reserve: 59 women with premature ovarian failure (POF) and 42 poor responders (PR) to OH. A Taqman copy number assay revealed a significant mtDNA depletion (P<0.001) in both POF and PR women in comparison with 43 women of similar age and intact ovarian reserve, or 53 very old women with a previous physiological menopause. No pathogenic variations in the mitochondrial DNA polymerase γ (POLG) gene were detected in 57 POF or PR women with low blood mtDNA content. In conclusion, blood cell mtDNA depletion is a frequent finding among women with premature ovarian aging, suggesting that a still undetermined but generalized mitochondrial defect may frequently predispose to POI which could then be considered a form of anticipated aging in which the ovarian defect may represent the first manifestation. The determination of mtDNA content in blood may become an useful tool for the POI risk prediction.     

Loss of ovarian function and the risk of ovarian cancer

Animal models with premature ovarian failure resulting from the loss or depletion of germ cells consistently develop ovarian surface epithelial cell hyperplasia with invasion into the stroma and the development of ovarian tubular adenomas. In human ovaries, deep epithelial invaginations and inclusion cysts occur at increasing frequency with age and are thought to be the structures from which the majority of ovarian cancers arise. A feature that is common to these animal models and to post-menopausal women is a deficiency in the number of oocytes. The potential consequences of the loss or depletion of female germ cells, naturally or otherwise, include failure of follicle development, significant reductions in oestrogen and progesterone levels and elevation of circulating levels of gonadotropins. This review will consider the way in which these structural and hormonal changes affect ovarian cancer risk. Some lessons may be learned from gonad formation, since notable similarities exist between ovarian tumorigenesis and embryonic gonadogenesis including fragmentation of the basement membrane underlying the coelomic (surface) epithelium, the potential for the migration of epithelial cells into the gonad and the importance of the germ cells for the regulation of ovarian structure and function. Research was supported by grants from the National Cancer Institute of Canada and the Canadian Institutes of Health Research.     

Granulosa cell-specific inactivation of follistatin causes female fertility defects

Follistatin plays an important role in female physiology by regulating FSH levels through blocking activin actions. Failure to regulate FSH has been implicated as a potential cause of premature ovarian failure. Premature ovarian failure is characterized by amenorrhea, infertility, and elevated gonadotropin levels in women under the age of 40. Because follistatin is essential for postnatal viability, we designed a cre/loxP conditional knockout system to render the follistatin gene null specifically in the granulosa cells of the postnatal ovary using Amhr2cre transgenic mice. The follistatin conditional knockout females develop fertility defects, including reduced litter number and litter sizes and, in the most severe case, infertility. Reduced numbers of ovarian follicles, ovulation and fertilization defects, elevated levels of serum FSH and LH, and reduced levels of testosterone were observed in these mice. These findings demonstrate that compromising granulosa cell follistatin function leads to findings similar to those characterized in premature ovarian failure. Follistatin conditional knockouts may therefore be a useful model with which to further study this human syndrome. These studies are the first report of a granulosa cell-specific deletion of a gene in the postnatal ovary and have important implications for future endeavors to generate ovary-specific knockout mouse models.     

Cytogenetic abnormalities in Tunisian women with premature ovarian failure

To identify the distribution of chromosome abnormalities among Tunisian women with premature ovarian failure (POF) referred to the department of Cytogenetic at the Pasteur Institute of Tunis (Tunisia), standard cytogenetic analysis was carried out in a total of 100 women younger than 40 affected with premature ovarian failure. We identified 18 chromosomal abnormalities, including seven X-numerical anomalies in mosaic and non-mosaic state (45,X; 47,XXX), four sex reversal, three X-structural abnormalities (terminal deletion and isochromosomes), one autosomal translocation and one supernumerary marker. The overall prevalence of chromosomal abnormalities was 18% in our cohort. X chromosome aneuploidy was the most frequent aberration. This finding confirms the essential role of X chromosome in ovarian function and underlies the importance of cytogenetic investigations in the routine management of POF.     

Founding BRCA1 mutations in hereditary breast and ovarian cancer in southern Sweden.

Nine different germ-line mutations in the BRCA1 breast and ovarian cancer susceptibility gene were identified in 15 of 47 kindreds from southern Sweden, by use of SSCP and heteroduplex analysis of all exons and flanking intron region and by a protein-truncation test for exon 11, followed by direct sequencing. All but one of the mutations are predicted to give rise to premature translation termination and include seven frameshift insertions or deletions, a nonsense mutation, and a splice acceptor site mutation. The remaining mutation is a missense mutation (Cys61Gly) in the zinc-binding motif. Four novel Swedish founding mutations were identified: the nucleotide 2595 deletion A was found in five families, the C 1806 T nonsense mutation in three families, the 3166 insertion TGAGA in three families, and the nucleotide 1201 deletion 11 in two families. Analysis of the intragenic polymorphism D17S855 supports common origins of the mutations. Eleven of the 15 kindreds manifesting BRCA1 mutations were breast-ovarian cancer families, several of them with a predominant ovarian cancer phenotype. The set of 32 families in which no BRCA1 alterations were detected included 1 breast-ovarian cancer kindred manifesting clear linkage to the BRCA1 region and loss of the wild-type chromosome in associated tumors. Other tumor types found in BRCA1 mutation/haplotype carriers included prostatic, pancreas, skin, and lung cancer, a malignant melanoma, an oligodendroglioma, and a carcinosarcoma. In all, 12 of 16 kindreds manifesting BRCA1 mutation or linkage contained ovarian cancer, as compared with only 6 of the remaining 31 families (P<.001). The present study confirms the involvement of BRCA1 in disease predisposition for a subset of hereditary breast cancer families often characterized by ovarian cancers.     

Surface ultrastructure of uterine epithelial cells in women with premature ovarian failure following steroid hormone replacement

Scanning electron microscopy has been used to study the apical surface of uterine epithelial cells in women with premature ovarian failure following steroid hormone replacement therapy. A variety of ultrastructural characteristics are identified which could indicate a uterus that is receptive for blastocyst implantation.     

Preservation of fertility in females treated for cancer

Advancements of diagnosis and treatment have substantially improved cancer survival rates in the last few decades. The increasing number of survivors focuses attention on long-term effects caused by cancer treatment and its impact on quality of life. Ovarian failure is one of the major sequelae of cytotoxic chemotherapy and/or radiotherapy in female children and reproductive-age women. Oncologists should address the patients about fertility preservation options before therapy. Embryo cryopreservation is the only well-established method for females in preserving fertility; however other strategies including ovarian suppression, ovarian transposition and cryopreservation of oocytes and ovarian tissue are still experimental. Patients need advice and to know which are the most practical options for them. This article reviews the available fertility preservation methods in women, and the related issues including normal physiology of the ovary, effect of anticancer therapy on fertility, role of the oncologist and ethics. We performed a MEDLINE search from 1971 to 2011 in a similar way as Jensen et al. 2011, using the following MeSH terms: antineoplastic agents; ovarian failure; premature; infertility, female; fertility preservation; child and cancer; reproductive technologies, assisted.     

Integral role of GDF-9 and BMP-15 in ovarian function

The oocyte plays an important role in regulating and promoting follicle growth, and thereby its own development, by the production of oocyte growth factors that predominantly act on supporting granulosa cells via paracrine signaling. Genetic studies in mice demonstrated critical roles of two key oocyte-derived growth factors belonging to the transforming growth factor-β (TGF-β) superfamily, growth and differentiation factor-9 (GDF-9) and bone morphogenetic protein-15 (BMP-15), in ovarian function. The identification of Bmp15 and Gdf9 gene mutations as the causal mechanism underlying the highly prolific or infertile nature of several sheep strains in a dosage-sensitive manner also highlighted the crucial role these two genes play in ovarian function. Similarly, large numbers of mutations in the GDF9 and BMP15 genes have been identified in women with premature ovarian failure and in mothers of dizygotic twins. The purpose of this article is to review the genetic studies of GDF-9 and BMP-15 mutations identified in women and sheep, as well as describing the various knockout and overexpressing mouse models, and to summarize the molecular and biological functions that underlie the crucial role of these two oocyte factors in female fertility.     

Transcription factor FIGLA is mutated in patients with premature ovarian failure

Premature Ovarian Failure (POF) is a genetically heterogenous disorder that leads to hypergonadotropic ovarian failure and infertility. We screened 100 Chinese women with POF for mutations in the oocyte-specific gene FIGLA and identified three variants in four women: missense mutation c.11C --> A (p.A4E) was found in two women; deletion c. 15-36 del (p.G6fsX66), resulting in a frameshift that leads to haploinsufficiency, was found in one woman; and deletion c.419-421 delACA (p.140 delN) was found in one. Functional analyses by the yeast two-hybrid assay demonstrated that the p.140 delN mutation disrupted FIGLA binding to the TCF3 helix-loop-helix (HLH) domain. Our findings show that a subset of Chinese women with sporadic, premature ovarian failure harbor mutations in FIGLA.     

Biological aging and the etiology of aneuploidy

A prevalent hypothesis concerning the cause of the rise in aneuploid conceptions with maternal age is that the changes that accompany normal ovarian aging increase the rate of meiotic errors in the oocyte. Biological aging of the ovary is accompanied by a decline in both the total oocyte pool and the number of antral follicles maturing per cycle, as well as changes in the levels of circulating reproductive hormones. The biological aging hypothesis predicts that aneuploidy rates should be higher in women with a prematurely reduced oocyte pool, and that women with trisomic conceptions should show signs of earlier ovarian aging than women of the same chronological age without trisomic conceptions. Comprehensive studies of aneuploidy in groups of women with known causes of premature ovarian failure remain to be done, though anecdotal evidence does suggest increased rates of pregnancy loss and aneuploidy. Smoking, which is a well-documented cause of earlier ovarian aging, is not associated with an increase in aneuploid conceptions. Evidence from women with unilateral ovariectomies is inconsistent. Support for the biological aging hypothesis was provided by one study showing that menopause occurred about a year earlier in women with a trisomic spontaneous abortion compared to women with chromosomally normal conceptions. Associations between high FSH and pregnancies with Down syndrome and chromosomally abnormal spontaneous abortions have also been reported. However, the most direct test of the hypothesis, which compared antral follicle counts and hormonal levels in women with trisomic pregnancies and those with chromosomally normal pregnancies, failed to find a difference in the expected direction. A prospective study of FSH levels in women with subfertility also failed to find an association with the rate of pregnancy loss. The bulk of evidence thus suggests that, if the processes of biological aging are indeed related to aneuploidy, they probably involve factors other than those measured by oocyte or antral follicle pool size and reproductive hormone levels.     

X-linked premature ovarian failure: a complex disease

Involvement of the X chromosome in premature ovarian failure was demonstrated by the relatively frequent chromosomal rearrangements in patients, but the requirement of two X chromosomes for ovarian function was quite unexplained until recently. Review of the data on chromosomal rearrangements suggests that several genes along the X chromosomes contribute to ovarian function. In most instances, no single X chromosome gene has a causative role in premature ovarian failure, and the phenotype is likely to derive from the additive effect of X-linked and non-X-linked factors. Recent data on a small group of balanced X-autosome translocations showed that X-linked premature ovarian failure might also be caused by a different mechanism, namely position effect of the X chromosome on non-X-linked genes, and suggest a peculiar organization of the X chromosome during oogenesis.     

Use of clomiphene and luteinizing hormone/follicle stimulating hormone-releasing hormone in investigation of ovulatory failure.

A luteinizing hormone/follicle-stimulating hormone-releasing hormone (LH/FSH-RH) test was performed in 70 women with amenorrhoea or anovulatory infertility, or both, and a clomiphene stimulation test was also performed in 24 of these patients. Most patients responded to LH/FSH-RH with significant increases in LH and FSH. In women with gonadal dysgenesis or premature ovarian failure exaggerated responses were observed after LH/FSH-RH and there was no change in high basal LH levels after clomiphene. Patients with absent or impaired responses to LH/FSH-RH failed to respond to clomiphene. All patients with anovulatory menstrual cycles responded to both LH/FSH-RH and clomiphene, while seven out of 13 amenorrhoeic patients with a normal LH/FSH-RH response showed an early LH rise during clomiphene treatment and six were unresponsive. These results suggest a difference between the two groups at hypothalamic level with consequent therapeutic implications.     

Global uptake of fertility preservation by women undergoing cancer treatment: An unmet need in low to high-income countries

Although the incidence of cancers is on the rise globally, mortality has continued to decrease due to advances in early detection and treatment. Cancer treatments such as chemotherapy and radiotherapy can impact the reproductive capacity of survivors by inducing premature ovarian failure and subsequent infertility causing significant psychological distress with decreased quality of life. Despite the increasing need for fertility preservation services for the rising number of cancer survivors and the recent advances in assisted reproductive technology, many women with cancers in low, middle, and to a lesser extent, high-income countries have no access to these services. This article, therefore, presents an overview of the effect of cancer treatment on fertility, options of fertility preservation, and factors influencing fertility preservation utilization by women who had a cancer diagnosis. In addition, we discuss the availability, practices, and outcomes of fertility preservation services in low, middle, and high-income countries and highlight pragmatic steps to improving access to oncofertility care for women with cancers globally.     

已烯雌酚对免疫性卵巢早衰小鼠卵巢细胞凋亡的影响

目的探讨已烯雌酚对免疫性卵巢早衰小鼠卵巢颗粒细胞和卵母细胞凋亡的影响。方法以小鼠透明带3蛋白的第330～342个氨基酸的序列（NSSSSQFQIHGPR）合成透明带多肽并作免疫原,免疫SPF级BALB/c雌性小鼠。设对照、模型和已烯雌酚组。灌胃给药4周后,采用Tunel方法检测颗粒细胞与卵母细胞的细胞凋亡数并作统计学分析。结果已烯雌酚组可显著减少小鼠卵巢卵母细胞的凋亡率（P〈0.05）。结论已烯雌酚组能改善免疫性卵巢早衰小鼠体重降低症状并能诱导发情。已烯雌酚能改善免疫性卵巢早衰小鼠症状的机制可能是由于能有效地抑制卵母细胞的凋亡所引起的。     

Naturally occurring anti-albumin antibodies are responsible for false positivity in diagnosis of autoimmune premature ovarian failure.

Autoimmunity is a well-established causative factor of premature ovarian failure (POF), and evidence for the same has been well reported in the literature. Detection of specific autoantibodies remains the most practical clinical research marker of any autoimmune disease. Variation in efficiency and specificity in the detection of ovarian autoantibodies has been reported. However, the frequency of false positivity and a solution to overcome this has not yet been reported. Herein, we report autoantibody to albumin as the likely responsible agent for false positivity. Our data indicate that presence of naturally existing autoalbumin antibodies in the circulation of normal women is responsible for the false signal seen in SDS-PAGE Western blot analysis and in immunohistochemistry (IHC). Having shown the presence of anti-albumin antibody in normal women as well as in the sera of POF patients, we have developed a novel blocking agent to overcome this problem. A high titer polyclonal antibody against human serum albumin was generated. This antibody showed immunoreactivity to albumin obtained from various sources. Preincubation of Western blots and IHC sections with this antibody drastically reduced background signals. The advantage of using this blocking was evident by identification of specific anti-ovarian antibodies in a group of POF patients. This blocking procedure made it possible to obtain a clear indication of the ovarian antibody status in women presenting with autoimmune POF.     

NOBOX homeobox mutation causes premature ovarian failure

NOBOX (newborn ovary homeobox gene) is an oocyte-specific homeobox gene that plays a critical role in early folliculogenesis and represents a candidate gene for nonsyndromic ovarian failure. We investigated whether mutations in the NOBOX gene cause premature ovarian failure (POF). We sequenced the NOBOX gene in 96 white women with POF and discovered seven known single-nucleotide polymorphisms and four novel variations, two of which, p.Arg355His and p.Arg360Gln, cause missense mutations in the homeobox domain. Electrophoretic mobility shift assay (EMSA) confirmed that the missense mutation, p.Arg355His, disrupted NOBOX homeodomain binding to NOBOX DNA-binding element (NBE) and had a dominant negative effect on the binding of wild-type NOBOX to DNA. Our findings demonstrate that NOBOX mutations can cause POF.