Why have ovarian cancer mortality rates declined? Part I. Incidence

Effect of integrin‑linked kinase gene silencing on microRNA expression in ovarian cancer

Integrin‑linked kinase (ILK) is overexpressed in ovarian cancer (OC), and ILK gene silencing results in apoptosis in OC cells. In the present study, the mechanism by which ILK induces apoptosis was explored from the perspective of microRNA (miRNA) expression. Alterations in the global miRNA expression profile were detected using a miRNA microarray after OC cells were transduced with an ILK small hairpin RNA lentivirus. ILK silencing led to a significant upregulation of 14 miRNAs by at least 1.5‑fold. These findings were validated by reverse transcription‑quantitative polymerase chain reaction. A pathway analysis of experimentally validated target genes revealed the inhibition of multiple cancer‑associated signaling pathways and the wnt signaling pathway. Compared with cells transfected with scrambled RNA, the ILK‑silenced cells had remarkably lower expression of wnt ligands (wnt3a, wnt4 and wnt5a) and downstream β‑catenin. ILK silencing led to apoptosis of OC cells and impaired the migratory ability. Taken together, the present results suggested that miRNA‑mediated wnt pathway alterations are involved in the anti‑apoptotic role of ILK in OC. It was also indicated that ILK silencing reduced the ability of OC cells to adhere to fibronectin, which may lead to unstable focal contact. Consistently, the phosphorylation levels of focal adhesion kinase and RAC‑α serine/threonine protein kinase were downregulated. The present work demonstrated the first global miRNA expression profile of OC cells when ILK was inhibited, and this expression profile may provide a basis for the development of biomarkers and therapeutic targets for OC.

PAX8 is a potential marker for the diagnosis of primary epithelial ovarian cancer

The present study aimed to investigate the clinical significance of paired-box 8 (PAX8) in primary epithelial ovarian cancer (PEOC). Using immunohistochemical (IHC) staining, the expression of PAX8 in 60 patients with PEOC, 20 patients with ovarian benign lesions and 10 patients with metastatic ovarian cancer (MOC), was examined based on the clinicopathological profiles of the patients. The correlation between PAX8 expression and the clinicopathological parameters or prognosis of patients was statistically analyzed. PAX8 was revealed to be highly expressed in PEOC, but not in MOC, as indicated by IHC staining. The rate of positivity of PAX8 in PEOC was 92% (57/60) with no significant difference of PAX8 expression found between the various pathological types of PEOC (P=0.871). The rate of positivity of PAX8 in ovarian benign tumors was 85%, demonstrating no significant difference in comparison with that of PEOC (P=0.761). PAX8 staining and statistical analysis revealed that the higher the grade of PEOC, the less the cancer cell had differentiated (P=0.033) and the more the cancer had advanced according to International Federation of Gynaecological Oncologists (FIGO) staging (P=0.003). Survival rate statistics showed that PEOC patients with higher PAX8 expression exhibited a shorter postoperative survival rate (P=0.009). PAX8 was specifically expressed in PEOC, and its expression level was associated with the degree of cancer cell differentiation, FIGO stage, and survival rate, indicating that PAX8 is a potential marker for the diagnosis of PEOC.

Committee Opinion No. 716: The Role of the Obstetrician-Gynecologist in the Early Detection of Epithelial Ovarian Cancer in Women at Average Risk

Ovarian cancer is the second most common type of female reproductive cancer, and more women die from ovarian cancer than from cervical cancer and uterine cancer combined. Currently, there is no strategy for early detection of ovarian cancer that reduces ovarian cancer mortality. Taking a detailed personal and family history for breast, gynecologic, and colon cancer facilitates categorizing women based on their risk (average risk or high risk) of developing epithelial ovarian cancer. Women with a strong family history of ovarian, breast, or colon cancer may have hereditary breast and ovarian cancer syndrome (BRCA mutation) or hereditary nonpolyposis colorectal cancer (Lynch syndrome), and these women are at increased risk of developing ovarian cancer. Women with these conditions should be referred for formal genetic counseling to better assess their cancer risk, including their risk of ovarian cancer. If appropriate, these women may be offered additional testing for early detection of ovarian cancer. The use of transvaginal ultrasonography and tumor markers (such as cancer antigen 125), alone or in combination, for the early detection of ovarian cancer in average-risk women have not been proved to reduce mortality, and harms exist from invasive diagnostic testing (eg, surgery) resulting from false-positive test results. The patient and her obstetrician-gynecologist should maintain an appropriate level of suspicion when potentially relevant signs and symptoms of ovarian cancer are present.

High-grade serous carcinomas arise in the mouse oviduct via defects linked to the human disease

Recent studies have suggested that the most common and lethal type of 'ovarian' cancer, i.e. high-grade serous carcinoma (HGSC), usually arises from epithelium on the fallopian tube fimbriae, and not from the ovarian surface epithelium. We have developed Ovgp1-iCreERT2 mice in which the Ovgp1 promoter controls expression of tamoxifen-regulated Cre recombinase in oviductal epithelium - the murine equivalent of human fallopian tube epithelium (FTE). We employed Ovgp1-iCreERT2 mice to show that FTE-specific inactivation of several different combinations of tumour suppressor genes that are recurrently mutated in human HGSCs - namely Brca1, Trp53, Rb1, and Nf1 - results in serous tubal intraepithelial carcinomas (STICs) that progress to HGSC or carcinosarcoma, and to widespread metastatic disease in a subset of mice. The cancer phenotype is highly penetrant and more rapid in mice carrying engineered alleles of all four tumour suppressor genes. Brca1, Trp53 and Pten inactivation in the oviduct also results in STICs and HGSCs, and is associated with diffuse epithelial hyperplasia and mucinous metaplasia, which are not observed in mice with intact Pten. Oviductal tumours arise earlier in these mice than in those with Brca1, Trp53, Rb1 and Nf1 inactivation. Tumour initiation and/or progression in mice lacking conditional Pten alleles probably require the acquisition of additional defects, a notion supported by our identification of loss of the wild-type Rb1 allele in the tumours of mice carrying only one floxed Rb1 allele. Collectively, the models closely recapitulate the heterogeneity and histological, genetic and biological features of human HGSC. These models should prove useful for studying the pathobiology and genetics of HGSC in vivo, and for testing new approaches for prevention, early detection, and treatment. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Recent Trends in Ovarian Cancer Incidence and Relative Survival in the United States by Race/Ethnicity and Histologic Subtypes

Background: Incidence and survival rates of nonserous epithelial ovarian cancer in racial/ethnic minorities remain relatively unknown in the United States. We examined the trends in incidence and survival rates for epithelial ovarian cancer by histologic subtypes and race/ethnicity.Methods: Ovarian cancer incidence and mortality data from 2000 to 2013 were obtained from the Surveillance, Epidemiology, and End Results database. Age-adjusted incidence rate, incidence rate ratio, and annual percentage changes (APC) were calculated by histology and race/ethnicity subgroups and stratified by age at diagnosis. Five-year relative survival rates were calculated by stage and race/ethnicity.Results: A small but significant decrease in incidence rates was seen in non-Hispanic white (NHW), non-Hispanic black (NHB), and Hispanic women (APC -1.58, -0.84, and -1.31, respectively), while incidence rates remained relatively stable in Asian women (APC -0.37). With exception of significant increase in the incidence rate of clear cell carcinoma among Asian woman (APC 1.85), an overall trend toward decreasing incidence rates was seen across histologic subtypes and age-strata, although not all results were statistically significant. Compared with NHW women, NHB women experienced poorer 5-year survival at every stage across histologic subtypes, while Hispanic and Asian women had equivalent or better survival.Conclusions: Over the last decade, incidence rates of epithelial ovarian cancer in the United States have decreased or remained stable across race/ethnic and histologic subgroups, except for clear cell carcinoma. Survival remains poorest among NHB women.Impact: Comparative histologic subtype distribution and incidence trends do not explain the ovarian cancer survival disparity disproportionately affecting NHB women. Cancer Epidemiol Biomarkers Prev; 26(10); 1511-8. ©2017 AACR.

Opportunistic Salpingectomy as an Ovarian Cancer Primary Prevention Strategy

Ovarian cancer is the most lethal form of all gynecologic malignancies. The presenting clinical symptoms of ovarian cancer are very vague and often appear late in the course of disease. Hence, most patients are diagnosed at later stages. At present, there is no effective screening of ovarian cancer. Primary prevention could be considered a strategy to decrease the mortality from ovarian cancer, not only in women at high risk but also in those at low risk. Most "ovarian cancers," and more specifically the high-grade serous carcinoma (HGSC) subtype of ovarian cancer, actually could originate in the fallopian tube. Women who have known BRCA1 or BRCA2 germline mutations should be counseled regarding bilateral salpingo-oophorectomy, immediately after completion of childbearing, as the best strategy for reducing their risk of developing ovarian cancer. If the patient is reluctant, they should be counseled regarding risk-reducing salpingectomy when childbearing is complete followed by oophorectomy in the future. For women at average risk of ovarian cancer, risk-reducing salpingectomy should also be discussed and considered with patients at the time of any abdominal or pelvic surgery, hysterectomy or tubal ligation.

Awareness and Knowledge of Ovarian Cancer Symptoms and Risk Factors: A Survey of Jordanian Women

Ovarian cancer accounts for 3% of all female cancers and has a high mortality rate among gynecological malignancies. Early diagnosis carries a high survival rate of 93%. So, this study was carried out to assess the knowledge and awareness of Jordanian women about ovarian cancer symptoms and risk factors. A cross-sectional survey design was used; 896 women completed the survey. The mean of total symptoms recognized was low at level of 3.2 ( SD = 2.7) out of 10. The three highest known symptoms among women were as follows: extreme fatigue (43.2%), back pain (42.4%), and persistent pain in pelvic area (40.7%). The most commonly known risk factor was smoking (68.4%), followed by having ovarian cyst(s) (59.7%). Hence, with the absence of an effective screening program, a national awareness campaign is urgently needed to improve the public's understanding of symptoms and risk factors and increasing women's confidence in symptom recognition.

The nerve growth factor alters calreticulin translocation from the endoplasmic reticulum to the cell surface and its signaling pathway in epithelial ovarian cancer cells

Ovarian cancer is the seventh most common cancer among women worldwide, causing approximately 120,000 deaths every year. Immunotherapy, designed to boost the body's natural defenses against cancer, appears to be a promising option against ovarian cancer. Calreticulin (CRT) is an endoplasmic reticulum (ER) resident chaperone that, translocated to the cell membrane after ER stress, allows cancer cells to be recognized by the immune system. The nerve growth factor (NGF) is a pro-angiogenic molecule overexpressed in this cancer. In the present study, we aimed to determine weather NGF has an effect in CRT translocation induced by cytotoxic and ER stress. We treated A2780 ovarian cancer cells with NGF, thapsigargin (Tg), an ER stress inducer and mitoxantrone (Mtx), a chemotherapeutic drug; CRT subcellular localization was analyzed by immunofluorescence followed by confocal microscopy. In order to determine NGF effect on Mtx and Tg-induced CRT translocation from the ER to the cell membrane, cells were preincubated with NGF prior to Mtx or Tg treatment and CRT translocation to the cell surface was determined by flow cytometry. In addition, by western blot analyses, we evaluated proteins associated with the CRT translocation pathway, both in A2780 cells and human ovarian samples. We also measured NGF effect on cell apoptosis induced by Mtx. Our results indicate that Mtx and Tg, but not NGF, induce CRT translocation to the cell membrane. NGF, however, inhibited CRT translocation induced by Mtx, while it had no effect on Tg-induced CRT exposure. NGF also diminished cell death induced by Mtx. NGF effect on CRT translocation could have consequences in immunotherapy, potentially lessening the effectiveness of this type of treatment.

Recent developments have made female permanent contraception an increasingly attractive option, and pregnant women in particular ought to be counselled about it

BACKGROUND

Despite the increased prevalence of reversible contraception, global unintended pregnancy rates are stable. Mistakes, method failures, side effects, alcohol, stock-outs, fears, costs, delays, myths, religious interference, doctors with other priorities, traditions and lack of health professionals may all factor in. Yet these unintended pregnancies - nearly a hundred million annually - cause much individual suffering, and in the long run, can aggravate conflicts, poverty, forced emigration and climate change. Presently, non-poor women postpone childbearing because of longer educational trajectories and careers. Sterilisations are therefore less often regretted or coerced. For poor-resourced women with a completed family, an unwanted pregnancy often has serious consequences, including crossing the (extreme) poverty line in the wrong direction, choosing an unsafe abortion, or even death. Caesarean sections (CSs), which currently stand at around 23 million annually, are increasing. On an "intention-never-to-become-pregnant-again" analysis, choosing a partial, and even more so a total bilateral tubectomy to be implemented during an - anyway performed - CS is by far the most reliable and safe contraceptive choice compared to meaning to start female or male sterilisation or any other contraceptive method later, and it reduces the chance of a future ovarian carcinoma substantially. CSs make subsequent pregnancies more dangerous. Simultaneously, they provide convenient, potentially cost-free opportunities for voluntary permanent contraception (PC): particularly important if there is no guaranteed future access to reliable contraception, safe abortion and well-supervised labour.

PARTIAL SOLUTION

Millions of women are within reach of attaining freedom from the "tyranny of excessive fertility" when they have a CS. Therefore, any woman who might conceivably be of the firm opinion that her family will be (over) completed after delivery should antenatally have "what if you have a CS" counselling to assess whether she would like a tubectomy/ligation. Yet many are not provided with this option: leading to frequent regret, more often than having been giving that choice would.

CONCLUSION

Withholding antenatal counselling about the option of PC for in case the delivery might become a CS is very prevalent, yet often more medically risky, and morally questionable than when, even in labour, a doctor sometimes decides in the absence of earlier counselling, considering numerous factors, to provide the choice to undergo a concurrent sterilisation if s/he is convinced that would be in the patient's best interest.

RNASET2 silencing affects miRNAs and target gene expression pattern in a human ovarian cancer cell model

Ribonucleases (RNases) are hydrolytic enzymes endowed with the ability to either process or degrade ribonucleic acids. Among the many biological functions assigned to RNases, a growing attention has been recently devoted to the control of cancer growth, in the attempt to bring novel therapeutic approaches to clinical oncology. Indeed, several enzymes belonging to different ribonuclease families have been reported in the last decade to display a marked oncosuppressive activity in a wide range of experimental models. The human RNASET2 gene, the only member of the highly conserved T2/Rh/S family of endoribonucleolytic enzymes described in our species, has been shown to display oncosuppressive roles in both in vitro and in vivo models representing several human malignancies. In the present study, we extend previous findings obtained in ovarian cancer models to shed further light on the cell-autonomous roles played by this gene in the context of its oncosuppresive role and to show that RNASET2 silencing can significantly affect the transcriptional output in one of the most thoroughly investigated human ovarian cancer cell lines. Moreover, we report for the first time that RNASET2-mediated changes in the cell transcriptome are in part mediated by its apparent ability to affect the cell's microRNA expression pattern.

The Emerging Role of Tyrosine Kinase Inhibitors in Ovarian Cancer Treatment: A Systematic Review

The present systematic review summarizes current evidence regarding the mechanisms of action, the efficacy, and the adverse effects of tyrosine kinase inhibitors (TKIs) in ovarian cancer patients. Phase II and III clinical trials were sought in the PubMed database and in the Clinical Trials.gov registry through September 30, 2015. Seventy-five clinical trials regarding TKIs targeting mainly vascular endothelial growth factor receptor, epidermal growth factor receptor, platelet-derived growth factor receptor, and sarcoma tyrosine kinase (Src) were yielded. The most promising results were noted with cediranib, nintedanib, and pazopanib. However, drawing universal conclusions about the potential integration of TKIs in ovarian cancer therapy remains elusive. Furthermore, emerging challenges and directions for the future research are critically discussed.

Assessing the genetic architecture of epithelial ovarian cancer histological subtypes

Epithelial ovarian cancer (EOC) is one of the deadliest common cancers. The five most common types of disease are high-grade and low-grade serous, endometrioid, mucinous and clear cell carcinoma. Each of these subtypes present distinct molecular pathogeneses and sensitivities to treatments. Recent studies show that certain genetic variants confer susceptibility to all subtypes while other variants are subtype-specific. Here, we perform an extensive analysis of the genetic architecture of EOC subtypes. To this end, we used data of 10,014 invasive EOC patients and 21,233 controls from the Ovarian Cancer Association Consortium genotyped in the iCOGS array (211,155 SNPs). We estimate the array heritability (attributable to variants tagged on arrays) of each subtype and their genetic correlations. We also look for genetic overlaps with factors such as obesity, smoking behaviors, diabetes, age at menarche and height. We estimated the array heritabilities of high-grade serous disease ([Formula: see text] = 8.8 ± 1.1 %), endometrioid ([Formula: see text] = 3.2 ± 1.6 %), clear cell ([Formula: see text] = 6.7 ± 3.3 %) and all EOC ([Formula: see text] = 5.6 ± 0.6 %). Known associated loci contributed approximately 40 % of the total array heritability for each subtype. The contribution of each chromosome to the total heritability was not proportional to chromosome size. Through bivariate and cross-trait LD score regression, we found evidence of shared genetic backgrounds between the three high-grade subtypes: serous, endometrioid and undifferentiated. Finally, we found significant genetic correlations of all EOC with diabetes and obesity using a polygenic prediction approach.

Ovarian Cancer: The Fallopian Tube as the Site of Origin and Opportunities for Prevention

High-grade serous carcinoma (HGSC) is the most common and aggressive histotype of epithelial ovarian cancer (EOC), and it is the predominant histotype associated with hereditary breast and ovarian cancer syndrome (HBOC). Mutations in BRCA1 and BRCA2 are responsible for most of the known causes of HBOC, while mutations in mismatch repair genes and several genes of moderate penetrance are responsible for the remaining known hereditary risk. Women with a history of familial ovarian cancer or with known germline mutations in highly penetrant genes are offered the option of risk-reducing surgery that involves the removal of the ovaries and fallopian tubes (salpingo-oophorectomy). Growing evidence now supports the fallopian tube epithelia as an etiological site for the development of HGSC and consequently, salpingectomy alone is emerging as a prophylactic option. This review discusses the site of origin of EOC, the rationale for risk-reducing salpingectomy in the high-risk population, and opportunities for salpingectomy in the low-risk population.

Can advanced-stage ovarian cancer be cured?

Approximately 20% of women with advanced-stage ovarian cancer survive beyond 12 years after treatment and are effectively cured. Initial therapy for ovarian cancer comprises surgery and chemotherapy, and is given with the goal of eradicating as many cancer cells as possible. Indeed, the three phases of therapy are as follows: debulking surgery to remove as much of the cancer as possible, preferably to a state of no visible residual disease; chemotherapy to eradicate any microscopic disease that remains present after surgery; and second-line or maintenance therapy, which is given to delay disease progression among patients with tumour recurrence. If no cancer cells remain after initial therapy is completed, a cure is expected. By contrast, if residual cancer cells are present after initial treatment, then disease recurrence is likely. Thus, the probability of cure is contingent on the combination of surgery and chemotherapy effectively eliminating all cancer cells. In this Perspectives article, I present the case that the probability of achieving a cancer-free state is maximized through a combination of maximal debulking surgery and intraperitoneal chemotherapy. I discuss the evidence indicating that by taking this approach, cures could be achieved in up to 50% of women with advanced-stage ovarian cancer.

Why have ovarian cancer mortality rates declined? Part III. Prospects for the future

Over the last 40 years, the age-adjusted ovarian cancer mortality rate in the USA declined by 23%. The decline in mortality paralleled a decline in incidence, which was largely due to changes in reproductive risk factors. There was no reduction in ovarian cancer case-fatality at 12 years, indicating that improvements in early detection or in treatment did not contribute to the decline in mortality. Here, we discuss potential strategies to further reduce ovarian cancer mortality through prevention, early detection and treatment. The first approach is to increase genetic testing, in order to identify women who are at a high risk of developing ovarian cancer and offer them preventive bilateral salpingo-oophorectomy. At present, up to 17% of ovarian cancers are potentially preventable through population-based genetic testing of known ovarian cancer susceptibility genes. The second approach is to increase the proportion of ovarian cancer patients who achieve a status of no residual disease through primary debulking surgery and subsequently receive adjuvant intraperitoneal chemotherapy. We believe that through a combination of screening to better identify low-volume advanced stage ovarian cancer, aggressive surgery to leave no residual disease and adjuvant intraperitoneal chemotherapy, the cure rate of ovarian cancer might be improved significantly.