Pathophysiological Dynamics of Human Ovarian Surface Epithelial Cells in Epithelial Ovarian Carcinogenesis

A Comprehensive Discussion in Vaginal Cancer Based on Mechanisms, Treatments, Risk Factors and Prevention

Vaginal cancer is a rare and uncommon disease that is rarely discussed. Although vaginal cancer traditionally occurs in older postmenopausal women, the incidence of high-risk human papillomavirus (HPV)-induced cancers is increasing in younger women. Cervical cancer cells contain high-risk human papillomavirus (HPV) E6 and E7 proteins and inhibiting HPV gene expression leads the cells to stop proliferating and enter senescence. As E6, and E7 protein promoted the carcinogenesis mechanism, and here not only regulate the cellular degradation of P53, and pRb but also enhances the cell proliferation along with E6 protein targets the p53 for breakdown and subsequently promote the apoptotic cell death, and DNA repair inhibition, that is indispensable to the continue the lifecycle of the HPV. As a synchronous or metachronous tumor, vaginal cancer is frequently found in combination with cervical cancer. It is uncertain what causes invasive female vaginal organ cancer. HPV type 16 is the most often isolated HPV type in female vaginal organ cancers. Due to cancer’s rarity, case studies have provided the majority of etiologic findings. Many findings demonstrate that ring pessaries, chronic vaginitis, sexual behavior, birth trauma, obesity, vaginal chemical exposure, and viruses are all risk factors. Because of insufficient understanding and disease findings, we are trying to find the disease’s mechanism with the available data. We also address different risk factors, therapy at various stages, diagnosis, and management of vaginal cancer in this review.

Ovarian Cancer Stemness: Biological and Clinical Implications for Metastasis and Chemotherapy Resistance

Epithelial ovarian cancer is a highly lethal gynecological malignancy that is characterized by the early development of disseminated metastasis. Though ovarian cancer has been generally considered to preferentially metastasize via direct transcoelomic dissemination instead of the hematogenous route, emerging evidence has indicated that the hematogenous spread of cancer cells plays a larger role in ovarian cancer metastasis than previously thought. Considering the distinctive biology of ovarian cancer, an in-depth understanding of the biological and molecular mechanisms that drive metastasis is critical for developing effective therapeutic strategies against this fatal disease. The recent “cancer stem cell theory” postulates that cancer stem cells are principally responsible for tumor initiation, metastasis, and chemotherapy resistance. Even though the hallmarks of ovarian cancer stem cells have not yet been completely elucidated, metastasized ovarian cancer cells, which have a high degree of chemoresistance, seem to manifest cancer stem cell properties and play a key role during relapse at metastatic sites. Herein, we review our current understanding of the cell-biological mechanisms that regulate ovarian cancer metastasis and chemotherapy resistance, with a pivotal focus on ovarian cancer stem cells, and discuss the potential clinical implications of evolving cancer stem cell research and resultant novel therapeutic approaches.

Haploid selection drives new gene male germline expression

New genes are a major source of novelties, and a disproportionate amount of them are known to show testis expression in later phases of male gametogenesis in different groups such as mammals and plants. Here, we propose that this enhanced expression is a consequence of haploid selection during the latter stages of male gametogenesis. Because emerging adaptive mutations will be fixed faster if their phenotypes are expressed by haploid rather than diploid genotypes, new genes with advantageous functions arising during this unique stage of development have a better chance to become fixed. To test this hypothesis, expression levels of genes of differing evolutionary age were examined at various stages of Drosophila spermatogenesis. We found, consistent with a model based on haploid selection, that new Drosophila genes are both expressed in later haploid phases of spermatogenesis and harbor a significant enrichment of adaptive mutations. Additionally, the observed overexpression of new genes in the latter phases of spermatogenesis was limited to the autosomes. Because all male cells exhibit hemizygous expression for X-linked genes (and therefore effectively haploid), there is no expectation that selection acting on late spermatogenesis will have a different effect on X-linked genes in comparison to initial diploid phases. Together, our proposed hypothesis and the analyzed data suggest that natural selection in haploid cells elucidates several aspects of the origin of new genes by explaining the general prevalence of their testis expression, and a parsimonious solution for new alleles to avoid being lost by genetic drift or pseudogenization.

Clinical value of Xenopus kinesin-like protein 2 as a prognostic marker in patients with digestive system cancers: a systematic review and meta-analysis

Xenopus kinesin-like protein 2 (TPX2) is a microtubule-associated protein that plays an important role in spindle assembly and dynamics. However, the clinical and prognostic value of TPX2 in the digestive system cancers remains unclear. The objective of this review was to evaluate the association of TPX2 expression with disease-free survival (DFS), overall survival (OS), and clinicopathological features of digestive system cancers. The software Stata 12.0 was used to analyze the outcomes, including OS, disease-free survival (DFS), and clinicopathological characteristics. A total of 10 eligible studies with 906 patients were included. Elevated TPX2 expression was significantly associated with poor DFS (pooled hazard ratio [HR] =2.48, 95% confidence interval [CI]: 1.96–3.13) and OS (pooled HR =2.66, 95% CI: 2.04–3.48) of digestive system malignancies. Subgroup analyses showed that cancer type, sample size, study quality, and laboratory detection methods did not alter the significant prognostic value of TPX2. Additionally, TPX2 expression was found to be an independent predictive factor for DFS (HR =2.31, 95% CI: 1.78–3.01). TPX2 expression might be associated with TNM stage and pathological grade in digestive system cancer. In conclusion, TPX2 is an independent prognostic factor for survival of patients with digestive system cancer. Furthermore, its overexpression is associated with TNM stage and pathological grade in digestive system cancer.

Characterization of the mammalian RNA exonuclease 5/NEF-sp as a testis-specific nuclear 3' → 5' exoribonuclease

Ribonucleases catalyze maturation of functional RNAs or mediate degradation of cellular transcripts, activities that are critical for gene expression control. Here we identify a previously uncharacterized mammalian nuclease family member NEF-sp (RNA exonuclease 5 [REXO5] or LOC81691) as a testis-specific factor. Recombinant human NEF-sp demonstrates a divalent metal ion-dependent 3' → 5' exoribonuclease activity. This activity is specific to single-stranded RNA substrates and is independent of their length. The presence of a 2'-O-methyl modification at the 3' end of the RNA substrate is inhibitory. Ectopically expressed NEF-sp localizes to the nucleolar/nuclear compartment in mammalian cell cultures and this is dependent on an amino-terminal nuclear localization signal. Finally, mice lacking NEF-sp are viable and display normal fertility, likely indicating overlapping functions with other nucleases. Taken together, our study provides the first biochemical and genetic exploration of the role of the NEF-sp exoribonuclease in the mammalian genome.

Development of Follicle-Stimulating Hormone Receptor Binding Probes to Image Ovarian Xenografts

The Follicle-Stimulating Hormone Receptor (FSHR) is used as an imaging biomarker for the detection of ovarian cancer (OC). FSHR is highly expressed on ovarian tumors and involved with cancer development and metastatic signaling pathways. A decapeptide specific to the FSHR extracellular domain is synthesized and conjugated to fluorescent dyes to image OC cells in vitro and tumors xenograft model in vivo. The in vitro binding curve and the average number of FSHR per cell are obtained for OVCAR-3 cells by a high resolution flow cytometer. For the decapeptide, the measured EC50 was 160 μM and the average number of receptors per cell was 1.7 × 10⁷. The decapeptide molecular imaging probe reached a maximum tumor to muscle ratio five hours after intravenous injection and a dose-dependent plateau after 24-48 hours. These results indicate the potential application of a small molecular weight imaging probe specific to ovarian cancer through binding to FSHR. Based on these results, multimeric constructs are being developed to optimize binding to ovarian cells and tumors.

Pericellular proteolysis in cancer

Pericellular proteases have long been associated with cancer invasion and metastasis due to their ability to degrade extracellular matrix components. Recent studies demonstrate that proteases also modulate tumor progression and metastasis through highly regulated and complex processes involving cleavage, processing, or shedding of cell adhesion molecules, growth factors, cytokines, and kinases. In this review, we address how cancer cells, together with their surrounding microenvironment, regulate pericellular proteolysis. We dissect the multitude of mechanisms by which pericellular proteases contribute to cancer progression and discuss how this knowledge can be integrated into therapeutic opportunities.

Corosolic acid enhances the antitumor effects of chemotherapy on epithelial ovarian cancer by inhibiting signal transducer and activator of transcription 3 signaling

Resistance to chemotherapy poses a serious problem for the treatment of advanced epithelial ovarian cancer patients. The mechanisms of chemoresistance are complex and studies have implicated signal transducer and activator of transcription 3 (STAT3) signaling in the chemoresistance of cancer cells. The present study investigated whether corosolic acid (CA), which has been previously reported to be a STAT3 inhibitor, was able to increase the sensitivity to chemotherapeutic drugs in epithelial ovarian cancer cells. CA also markedly enhanced the anticancer effect of paclitaxel, cisplatin and doxorubicin. In addition, CA abrogated the cell-cell interactions between macrophages and epithelial ovarian cancer cells and inhibited the macrophage-induced activation of epithelial ovarian cancer cells. These data indicated that CA was able to reverse the chemoresistance of epithelial ovarian cancer cells and suppress the cell-cell interaction with tumorigenic macrophages. Thus, CA may be useful as an adjuvant treatment to patients with advanced ovarian and other types of cancer due to the multiple anticancer effects.

Clinicopathologic study of serous tubal intraepithelial carcinoma with invasive carcinoma: is serous tubal intraepithelial carcinoma a reliable feature for determining the organ of origin?

In the past several decades, the concept of serous ovarian carcinoma has been revised repeatedly. However, the exact pathogenesis remains controversial. The most popular current concept is origin from the epithelium of the fimbriated ends of the fallopian tubes. The objective of our study was to evaluate the characteristic clinical and morphologic features of serous tubal intraepithelial carcinoma (STIC) and associated invasive carcinomas. One hundred sixteen consecutive cases of STIC seen from 2007 to 2011 were included in this study. High-grade serous carcinoma (HGSC) with or without a mixed component was identified in 107 cases (92.2%), non-HGSC in 5 cases, and STICs without invasive carcinoma in 4 cases. Using conventional criteria, HGSCs were classified as fallopian tube in origin in 65 cases (60.7%), as ovarian in 30 (28.0%), as peritoneal in 9 (8.4%), and as endometrial in 3 (2.8%). Among the 107 cases with HGSCs, most STICs (86; 80%) were present unilaterally, whereas invasive tumors more commonly involved the ovaries bilaterally (79%; 84 cases). These findings support the hypothesis that STIC acts as a precursor lesion for most fallopian tube, ovarian, and peritoneal HGSCs, but not for endometrial HGSC.

Ovarian Cancer Is an Imported Disease: Fact or Fiction?

The cell of origin of ovarian cancer has been long debated. The current paradigm is that epithelial ovarian cancer (EOC) arises from the ovarian surface epithelium (OSE). OSE is composed of flat, nondescript cells more closely resembling the mesothelium lining the peritoneal cavity, with which it is continuous, rather than the various histologic types of ovarian carcinoma (serous, endometrioid, and clear cell carcinoma), which have a Müllerian phenotype. Accordingly, it has been argued that the OSE undergoes a process termed "metaplasia" to account for this profound morphologic transformation. Recent molecular and clinicopathologic studies not only have failed to support this hypothesis but also have provided evidence that EOC stems from Müllerian-derived extraovarian cells that involve the ovary secondarily, thereby calling into question the very existence of primary EOC. This new model of ovarian carcinogenesis proposes that fallopian tube epithelium (benign or malignant) implants on the ovary to give rise to both high-grade and low-grade serous carcinomas, and that endometrial tissue implants on the ovary and produces endometriosis, which can undergo malignant transformation into endometrioid and clear cell carcinoma. Thus, ultimately EOC is not ovarian in origin but rather is secondary, and it is logical to conclude that the only true primary ovarian neoplasms are germ cell and gonadal stromal tumors analogous to tumors in the testis. If this new model is confirmed, it has profound implications for the early detection and treatment of "ovarian cancer."

A maternally inherited autosomal point mutation in human phospholipase C zeta (PLCζ) leads to male infertility

BACKGROUND

Male factor and idiopathic infertility contribute significantly to global infertility, with abnormal testicular gene expression considered to be a major cause. Certain types of male infertility are caused by failure of the sperm to activate the oocyte, a process normally regulated by calcium oscillations, thought to be induced by a sperm-specific phospholipase C, PLCzeta (PLCζ). Previously, we identified a point mutation in an infertile male resulting in the substitution of histidine for proline at position 398 of the protein sequence (PLCζ(H398P)), leading to abnormal PLCζ function and infertility.

METHODS AND RESULTS

Here, using a combination of direct-sequencing and mini-sequencing of the PLCζ gene from the patient and his family, we report the identification of a second PLCζ mutation in the same patient resulting in a histidine to leucine substitution at position 233 (PLCζ(H233L)), which is predicted to disrupt local protein interactions in a manner similar to PLCζ(H398P) and was shown to exhibit abnormal calcium oscillatory ability following predictive 3D modelling and cRNA injection in mouse oocytes respectively. We show that PLCζ(H233L) and PLCζ(H398P) exist on distinct parental chromosomes, the former inherited from the patient's mother and the latter from his father. Neither mutation was detected utilizing custom-made single-nucleotide polymorphism assays in 100 fertile males and females, or 8 infertile males with characterized oocyte activation deficiency.

CONCLUSIONS

Collectively, our findings provide further evidence regarding the importance of PLCζ at oocyte activation and forms of male infertility where this is deficient. Additionally, we show that the inheritance patterns underlying male infertility are more complex than previously thought and may involve maternal mechanisms.

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.

The tumor-suppressor gene ARHI (DIRAS3) suppresses ovarian cancer cell migration through inhibition of the Stat3 and FAK/Rho signaling pathways

Ovarian cancers migrate and metastasize over the surface of the peritoneal cavity. Consequently, dysregulation of mechanisms that limit cell migration may be particularly important in the pathogenesis of the disease. ARHI is an imprinted tumor-suppressor gene that is downregulated in >60% of ovarian cancers, and its loss is associated with decreased progression-free survival. ARHI encodes a 26-kDa GTPase with homology to Ras. In contrast to Ras, ARHI inhibits cell growth, but whether it also regulates cell motility has not been studied previously. Here we report that re-expression of ARHI decreases the motility of IL-6- and epidermal growth factor (EGF)-stimulated SKOv3 and Hey ovarian cancer cells, inhibiting both chemotaxis and haptotaxis. ARHI binds to and sequesters Stat3 in the cytoplasm, preventing its translocation to the nucleus and localization in focal adhesion complexes. Stat3 siRNA or the JAK2 inhibitor AG490 produced similar inhibition of motility. However, the combination of ARHI expression with Stat3 knockdown or inhibition produced greatest inhibition in ovarian cancer cell migration, consistent with Stat3-dependent and Stat3-independent mechanisms. Consistent with two distinct signaling pathways, knockdown of Stat3 selectively inhibited IL-6-stimulated migration, whereas knockdown of focal adhesion kinase (FAK) preferentially inhibited EGF-stimulated migration. In EGF-stimulated ovarian cancer cells, re-expression of ARHI inhibited FAK(Y397) and Src(Y416) phosphorylation, disrupted focal adhesions, and blocked FAK-mediated RhoA signaling, resulting in decreased levels of GTP-RhoA. Re-expression of ARHI also disrupted the formation of actin stress fibers in a FAK- and RhoA-dependent manner. Thus, ARHI has a critical and previously uncharacterized role in the regulation of ovarian cancer cell migration, exerting inhibitory effects on two distinct signaling pathways.

POLD2 and KSP37 (FGFBP2) correlate strongly with histology, stage and outcome in ovarian carcinomas

BACKGROUND

Epithelial ovarian cancer (EOC) constitutes more than 90% of ovarian cancers and is associated with high mortality. EOC comprises a heterogeneous group of tumours, and the causes and molecular pathology are essentially unknown. Improved insight into the molecular characteristics of the different subgroups of EOC is urgently needed, and should eventually lead to earlier diagnosis as well as more individualized and effective treatments. Previously, we reported a limited number of mRNAs strongly upregulated in human osteosarcomas and other malignancies, and six were selected to be tested for a possible association with three subgroups of ovarian carcinomas and clinical parameters.

METHODOLOGY/PRINCIPAL FINDINGS

The six selected mRNAs were quantified by RT-qPCR in biopsies from eleven poorly differentiated serous carcinomas (PDSC, stage III-IV), twelve moderately differentiated serous carcinomas (MDSC, stage III-IV) and eight clear cell carcinomas (CCC, stage I-IV) of the ovary. Superficial scrapings from six normal ovaries (SNO), as well as biopsies from three normal ovaries (BNO) and three benign ovarian cysts (BBOC) were analyzed for comparison. The gene expression level was related to the histological and clinical parameters of human ovarian carcinoma samples. One of the mRNAs, DNA polymerase delta 2 small subunit (POLD2), was increased in average 2.5- to almost 20-fold in MDSC and PDSC, respectively, paralleling the degree of dedifferentiation and concordant with a poor prognosis. Except for POLD2, the serous carcinomas showed a similar transcription profile, being clearly different from CCC. Another mRNA, Killer-specific secretory protein of 37 kDa (KSP37) showed six- to eight-fold higher levels in CCC stage I compared with the more advanced staged carcinomas, and correlated positively with an improved clinical outcome.

CONCLUSIONS/SIGNIFICANCE

We have identified two biomarkers which are markedly upregulated in two subgroups of ovarian carcinomas and are also associated with stage and outcome. The results suggest that POLD2 and KSP37 might be potential prognostic biomarkers.

Asian society of gynecologic oncology workshop 2010

This workshop was held on July 31-August 1, 2010 and was organized to promote the academic environment and to enhance the communication among Asian countries prior to the 2nd biennial meeting of Australian Society of Gynaecologic Oncologists (ASGO), which will be held on November 3-5, 2011. We summarized the whole contents presented at the workshop. Regarding cervical cancer screening in Asia, particularly in low resource settings, and an update on human papillomavirus (HPV) vaccination was described for prevention and radical surgery overview, fertility sparing and less radical surgery, nerve sparing radical surgery and primary chemoradiotherapy in locally advanced cervical cancer, were discussed for management. As to surgical techniques, nerve sparing radical hysterectomy, optimal staging in early ovarian cancer, laparoscopic radical hysterectomy, one-port surgery and robotic surgery were introduced. After three topics of endometrial cancer, laparoscopic surgery versus open surgery, role of lymphadenectomy and fertility sparing treatment, there was a special additional time for clinical trials in Asia. Finally, chemotherapy including neo-adjuvant chemotherapy, optimal surgical management, and the basis of targeted therapy in ovarian cancer were presented.

Reduced amounts and abnormal forms of phospholipase C zeta (PLCzeta) in spermatozoa from infertile men

BACKGROUND

In mammals, oocyte activation at fertilization is thought to be induced by the sperm-specific phospholipase C zeta (PLCzeta). However, it still remains to be conclusively shown that PLCzeta is the endogenous agent of oocyte activation. Some types of human infertility appear to be caused by failure of the sperm to activate and this may be due to specific defects in PLCzeta.

METHODS AND RESULTS

Immunofluorescence studies showed PLCzeta to be localized in the equatorial region of sperm from fertile men, but sperm deficient in oocyte activation exhibited no specific signal in this same region. Immunoblot analysis revealed reduced amounts of PLCzeta in sperm from infertile men, and in some cases, the presence of an abnormally low molecular weight form of PLCzeta. In one non-globozoospermic case, DNA analysis identified a point mutation in the PLCzeta gene that leads to a significant amino acid change in the catalytic region of the protein. Structural modelling suggested that this defect may have important effects upon the structure and function of the PLCzeta protein. cRNA corresponding to mutant PLCzeta failed to induce calcium oscillations when microinjected into mouse oocytes. Injection of infertile human sperm into mouse oocytes failed to activate the oocyte or trigger calcium oscillations. Injection of such infertile sperm followed by two calcium pulses, induced by assisted oocyte activation, activated the oocytes without inducing the typical pattern of calcium oscillations.

CONCLUSIONS

Our findings illustrate the importance of PLCzeta during fertilization and suggest that mutant forms of PLCzeta may underlie certain types of human male infertility.

Oncogenic transformation of human ovarian surface epithelial cells with defined cellular oncogenes

Ovarian surface epithelium (OSE) is considered to give rise to epithelial ovarian carcinomas (EOCs). To elucidate early processes contributing to the development of EOCs from the OSE, two batches of primary human OSE cells were transduced with non-viral human genes (mutant Cdk4, cyclinD1 and hTERT) so as to efficiently establish normal diploid OSE cells without chromosomal instability. Then defined genetic alterations frequently observed in EOCs were transduced into the OSE cells. A combination of p53 inactivation and oncogenic Kras transduction did not confer tumor-forming ability in immunodeficient mice, though additional transduction of Akt or combined transduction of c-myc with bcl-2 did result in tumor formation. In the latter case, tumors demonstrated phenotypes reminiscent of human EOCs, including cytokeratin expression, a highly aggressive phenotype, metastatic behavior and formation of ascites. These results indicate that inactivation of p53 and activation of the Ras pathway play critical roles in ovarian carcinogenesis in co-operation with the Akt or c-myc pathways. This first in vitro model system faithfully recapitulating the development of EOCs using normal human OSE cells should greatly facilitate further studies of EOCs.

The relationship of endometriosis and ovarian malignancy: a review

OBJECTIVE

To review the malignant potential of endometriosis based on epidemiologic, histopathologic, and molecular data.

DESIGN

Literature review.

RESULT(S)

The pathogenesis of endometriosis remains unclear. The histopathologic development of endometriosis has undergone long-term investigation. Studies have confirmed histologic transition from benign endometriosis to ovarian malignancy, including malignant transformation of extraovarian endometriosis. The prevalence of endometriosis in patients with epithelial ovarian cancer, especially in endometrioid and clear cell types, has been confirmed to be higher than in the general population. Ovarian cancers and adjacent endometriotic lesions have shown common genetic alterations, such as PTEN, p53, and bcl gene mutations, suggesting a possible malignant genetic transition spectrum. Furthermore, endometriosis has been associated with a chronic inflammatory state leading to cytokine release. These cytokines act in a complex system in which they induce or repress their own synthesis and can cause unregulated mitotic division, growth and differentiation, and migration or apoptosis similar to malignant mechanisms.

CONCLUSION(S)

The malignant potential of endometriosis holds serious implications for management, such as the need for earlier and more meticulous surgical intervention for complete disease treatment.

Sperm competition and sperm cooperation: the potential role of diploid and haploid expression

Sperm competition is a powerful selective force driving the evolution of sperm shape and function. Recent findings suggest that sperm cooperation is a potential evolutionary response to sperm competition. Sperm cooperation may enhance the performance of the ejaculate increasing a male's chance to outcompete rival males in competition for fertilisation. Whether and how sperm cooperation may evolve is the focal point of this review. The relative importance of haploid and diploid gene expression for the evolution of sperm cooperation and the potential conflict of interest between (i) haploid sperm and diploid male and (ii) among sibling sperm, since sibling sperm only share an average of 50% of their genes in a diploid organism, are discussed. Furthermore, sperm cooperation is defined and the literature for empirical evidence of sperm cooperation is reviewed in light of the author's definitions.

A molecular analysis of the population of mRNA in bovine spermatozoa

Spermiogenesis represents the transition from haploid spermatids to spermatozoa. This process entails an extreme condensation of the nucleus and a loss of nearly all cytoplasmic content. The presence of messenger RNAs in the spermatozoa has previously been shown. Generally, these transcripts are considered to be remnants of spermiogenesis. However, it has recently been proposed that there may exist a function for these sperm-associated RNAs. To address the possibility of a functional role for these transcripts, we sought to investigate and characterize the RNA pool found in bovine spermatozoa. The main goals of this study were to examine RNA integrity and survey the mRNA found in spermatids and spermatozoa. Assessment of mRNAs integrity was performed by three approaches: microelectrophoresis, comparative smearing after global amplification, and PCR amplification of target sequences located either in the 5' or the 3' ends, while mRNAs survey was performed by microarray hybridizations. RNA integrity studies in the spermatozoa showed a majority of low molecular size fragments indicating a natural segmentation of the mRNA population. The mRNA survey indicated that the sperm transcriptome harbors a complex mixture of messengers implicated in a wide array of cell functions and representing a large subset of transcripts found in spermatids. Subsequently, such sperm RNA profiling could allow the molecular diagnosis of male gamete quality.

Histological and Immunohistochemical Evaluation of Canine Ovary

In the present study, 15 canine ovaries without morphological lesions were examined histologically and immunohistochemically by using a large number of proteins including AE1/AE3, cytokeratin7 (CK7), CK13, CK20, vimentin, desmin, alpha smooth muscle actin (alphaSMA), calponin, S100, Neurofilaments, Inhibinalpha, placental alkaline phosphatase (PLAP) and neuron-specific enolase. Ovarian structures observed in this study included surface epithelium (SE), cortical tubules (CT), tunica albuginea (TA), stromal cells (SC), internal endocrine cells (IE), rete ovarii (RO) and fallopian tubes (FT). SE, CT, RO and FT were broadly immunoreactive for desmin. Besides AE1/AE3 and vimentin, desmin was also closely linked to these structures. Rete ovarii forming a reticular structure showed a positive reaction to S100. Surface epithelium was immunoreactive for PLAP at a significantly high level. In conclusion, these results indicate a specific segment of immunoreactivity as well as the broad range of immunoreactivity in canine ovary. The distinct patterns of immunoreactive for various kinds of proteins will play an important role in facilitating their identification and discrimination even in a normal canine ovary with a complex structure.

Cytogenetic instability in ovarian epithelial cells from women at risk of ovarian cancer

Fanconi anemia is an inherited cancer predisposition disease characterized by cytogenetic and cellular hypersensitivity to cross-linking agents. Seeking evidence of Fanconi anemia protein dysfunction in women at risk of ovarian cancer, we screened ovarian surface epithelial cells from 25 primary cultures established from 22 patients using cross-linker hypersensitivity assays. Samples were obtained from (a) women at high risk for ovarian cancer with histologically normal ovaries, (b) ovarian cancer patients, and (c) a control group with no family history of breast or ovarian cancer. In chromosomal breakage assays, all control cells were mitomycin C (MMC) resistant, but eight samples (five of the six high-risk and three of the eight ovarian cancer) were hypersensitive. Lymphocytes from all eight patients were MMC resistant. Only one of the eight patients had a BRCA1 germ-line mutation and none had BRCA2 mutations, but FANCD2 was reduced in five of the eight. Ectopic expression of normal FANCD2 cDNA increased FANCD2 protein and induced MMC resistance in both hypersensitive lines tested. No FANCD2 coding region or promoter mutations were found, and there was no genomic loss or promoter methylation in any Fanconi anemia genes. Therefore, in high-risk women with no BRCA1 or BRCA2 mutations, tissue-restricted hypersensitivity to cross-linking agents is a frequent finding, and chromosomal breakage responses to MMC may be a sensitive screening strategy because cytogenetic instability identified in this way antedates the onset of carcinoma. Inherited mutations that result in tissue-specific FANCD2 gene suppression may represent a cause of familial ovarian cancer.

Gonadotropins and ovarian carcinogenesis: a new era of basic research and its clinical implications

The possible relationship between gonadotropins and ovarian carcinoma development has received much attention, and in recent years, great progress has been made in basic and epidemiologic research about this issue. Gonadotropins sensitivity in the ovarian surface epithelium (OSE) and in a subset of ovarian carcinomas has been established in vivo and in vitro. Gonadotropins have been shown to induce various biologic actions in the OSE and ovarian carcinoma cells, such as changes in cell proliferation, apoptosis, cell adhesion, and chemosensitivity. These basic studies strongly suggest that gonadotropins are involved in the development and progression of ovarian carcinoma. In contrast, although earlier studies showed a significant risk of infertility therapy for ovarian carcinoma development, subsequent studies reported only slightly increased or no significant increased risk of gonadotropin stimulation and/or assisted reproductive technologies for ovarian carcinoma development. Therefore, the association between ovarian stimulation and ovarian carcinoma remains controversial. Nevertheless, since development of ovarian carcinoma in infertile women during infertility treatment is a serious concern for gynecologists, this review also covers important points for clinical practice, especially the issue of early detection of ovarian carcinoma.

Establishment of an immortalised human ovarian surface epithelial cell line without chromosomal instability

Epithelial ovarian carcinoma is thought to derive from ovarian surface epithelium (OSE). The black box of the early molecular changes in ovarian carcinogenesis is being interpreted by the development of experimental systems employing immortalised human OSE cells. However, the existing cell lines of the OSE cells have limited utility due to chromosomal instability. Our goal was to establish new immortalised human OSE cells that retain the original characteristics of the primary cells without chromosomal alterations. Using primary human OSE cells obtained from a postmenopausal patient with endometrial cancer, five cell lines (‘HOSE1’ lines) were newly established by infection with retroviral expression vectors containing type 16 human papillomavirus (HPV-16) E6, E7, a variant E6 (E6Δ151), and Bmi1 polycomb gene, in combination with telomerase reverse transcriptase (hTERT). Consequently, five HOSE1s cell lines, HOSE1s-E6/hTERT, -E7/hTERT, -E6/E7/hTERT, -E6Δ151/E7/hTERT, and -E6Δ151/Bmi1/hTERT, grew beyond the population doubling number of 200. These cell lines, except for HOSE1-E6/hTERT, essentially showed the original features of the primary human OSE cells. Of them, HOSE1-E7/hTERT preserved diploidy in a kariotype analysis, and did not show transformed phenotypes in anchorage-independent growth and tumour formation. Thus, HOSE1-E7/hTERT may provide a novel model system with which to investigate the mechanisms of early molecular changes.