Evaluating the ovarian cancer gonadotropin hypothesis: a candidate gene study

Circular RNA circRPS19 promotes chicken granulosa cell proliferation and steroid hormone synthesis by interrupting the miR-218-5p/INHBB axis

Ovarian follicle development is an important physiological activity for females and makes great significance in maintaining female health and reproduction performance. The development of ovarian follicle is mainly affected by the granulosa cells (GCs), whose growth is regulated by a variety of factors. Here, we identified a novel circular RNA (circRNA) derived from the Ribosomal protein S19 (RPS19) gene, named circRPS19, which is differentially expressed during chicken ovarian follicle development. Further explorations identified that circRPS19 promotes GCs proliferation and steroid hormone synthesis. Furthermore, circRPS19 was found to target and regulate miR-218-5p through a competitive manner with endogenous RNA (ceRNA). Functionals investigation revealed that miR-218-5p attenuates GCs proliferation and steroidogenesis, which is opposite to that of circRPS19. In addition, we also confirmed that circRPS19 upregulates the expression of Inhibin beta B subunit (INHBB) by binding with miR-218-5p to facilitate GCs proliferation and steroidogenesis. Overall, this study revealed that circRPS19 regulates GCs development by releasing the repression of miR-218-5p on INHBB, which suggests a novel mechanism in respect to circRNA and miRNA regulation in ovarian follicle development.

Metabolic syndrome and breast cancer: a dangerous association for postmenopausal women

BACKGROUND

Breast cancer(BC) is the most common cancer in women worldwide, the relationship between metabolic syndrome(MetS) and BC needs to be better clarified. Today the early diagnosis of breast cancer(BC) is yet a challenging problem in clinical practice, so the evidence that a well identified population of postmenopausal women, affected by MetS, presents a high risk, of breast cancer occurrence, is useful for breast cancer prevention. Our study aims to assess the prevalence of metabolic syndrome, diagnosed according to current guidelines, in postmenopausal women with breast cancer, and its role as an independent risk factor.

RESULTS

MetS rate was significantly higher among women affected by BC:10.1%, 33 women, than CG:5.4%, 18 women, Chi-squared4.8,Odds ratio1.94,c.i.95%,p<0.02. Metabolic cardiomyopathy rate was significantly higher among women affected by BC:5.8%, 18 women, than CG:1.8%, 6 women, Chi-squared6.5,Odds ratio3.2,c.i.95%,p<0.01. Otherwise MetS rate without cardiomyopathy was higher among women affected by BC:4.8%, 15 women, than CG:3.4%, 11 women, but in a not statistically significant way, Chi-squared0.8,Odds ratio1.35,c.i.95%,p<0.36.

CONCLUSION

There was a significant relationship, in our population, between MetS and BC, adding evidence to this controversial association, the relationship was even tighter, when restricted to women affected by metabolic cardiomyopathy; otherwise it, restricted to women affected by MetS, without metabolic cardiomyopathy, was not statistically significant. Since the prevalence of MetS is increasing worldwide, just like the incidence of BC, an intervention is needed to improve physical activity and weight reduction to decrease the MetS rate.

Mechanisms of High-Grade Serous Carcinogenesis in the Fallopian Tube and Ovary: Current Hypotheses, Etiologic Factors, and Molecular Alterations

Ovarian high-grade serous carcinomas (HGSCs) are a heterogeneous group of diseases. They include fallopian-tube-epithelium (FTE)-derived and ovarian-surface-epithelium (OSE)-derived tumors. The risk/protective factors suggest that the etiology of HGSCs is multifactorial. Inflammation caused by ovulation and retrograde bleeding may play a major role. HGSCs are among the most genetically altered cancers, and TP53 mutations are ubiquitous. Key driving events other than TP53 mutations include homologous recombination (HR) deficiency, such as BRCA 1/2 dysfunction, and activation of the CCNE1 pathway. HR deficiency and the CCNE1 amplification appear to be mutually exclusive. Intratumor heterogeneity resulting from genomic instability can be observed at the early stage of tumorigenesis. In this review, I discuss current carcinogenic hypotheses, sites of origin, etiologic factors, and molecular alterations of HGSCs.

Metabolic syndrome and breast cancer: a dangerous association for postmenopausal women

BACKGROUND

Breast cancer(BC) is the most common cancer in women worldwide, the relationship between metabolic syndrome(MetS) and BC needs to be better clarified. Today the early diagnosis of breast cancer(BC) is yet a challenging problem in clinical practice, so the evidence that a well identified population of postmenopausal women, affected by MetS, presents a high risk, of breast cancer occurrence, is useful for breast cancer prevention. Our study aims to assess the prevalence of metabolic syndrome, diagnosed according to current guidelines, in postmenopausal women with breast cancer, and its role as an independent risk factor.

RESULTS

MetS rate was significantly higher among women affected by BC:10.1%, 33 women, than CG:5.4%, 18 women, Chi-squared4.8,Odds ratio1.94,c.i.95%,p<0.02. Metabolic cardiomyopathy rate was significantly higher among women affected by BC:5.8%, 18 women, than CG:1.8%, 6 women, Chi-squared6.5,Odds ratio3.2,c.i.95%,p<0.01. Otherwise MetS rate without cardiomyopathy was higher among women affected by BC:4.8%, 15 women, than CG:3.4%, 11 women, but in a not statistically significant way, Chi-squared0.8,Odds ratio1.35,c.i.95%,p<0.36.

CONCLUSION

There was a significant relationship, in our population, between MetS and BC, adding evidence to this controversial association, the relationship was even tighter, when restricted to women affected by metabolic cardiomyopathy; otherwise it, restricted to women affected by MetS, without metabolic cardiomyopathy, was not statistically significant. Since the prevalence of MetS is increasing worldwide, just like the incidence of BC, an intervention is needed to improve physical activity and weight reduction to decrease the MetS rate.

Translational Theragnosis of Ovarian Cancer: where do we stand?

BACKGROUND

Ovarian cancer is the second most common gynecologic malignancy, accounting for approximately 220,000 deaths annually worldwide. Despite radical surgery and initial high response rates to platinum- and taxane-based chemotherapy, most patients experience a relapse, with a median progression-free survival of only 18 months. Overall survival is approximately 30% at 5 years from the diagnosis. In comparison, patients out from breast cancer are more than 80 % after ten years from the disease discovery. In spite of a large number of published fundamental and applied research, and clinical trials, novel therapies are urgently needed to improve outcomes of the ovarian cancer. The success of new drugs development in ovarian cancer will strongly depend on both fully genomic disease characterization and, then, availability of biomarkers able to identify women likely to benefit from a given new therapy.

METHODS

In this review, the focus is given to describe how complex is the diseases under the simple name of ovarian cancer, in terms of cell tumor types, histotypes, subtypes, and specific gene mutation or differently expressed in the tumor with respect the healthy ovary. The first- and second-line pharmacological treatment clinically used over the last fifty years are also described. Noteworthy achievements in vitro and in vivo tested new drugs are also summarized. Recent literature related to up to date ovarian cancer knowledge, its detection by biomarkers and chemotherapy was searched from several articles on Pubmed, Google Scholar, MEDLINE and various Governmental Agencies till April 2019.

RESULTS

The papers referenced by this review allow a deep analysis of status of the art in the classification of the several types of ovarian cancer, the present knowledge of diagnosis based on biomarkers and imaging techniques, and the therapies developed over the past five decades.

CONCLUSION

This review aims at stimulating more multi-disciplinary efforts to identify a panel of novel and more specific biomarkers to be used to screen patients for a very early diagnosis, to have prognosis and therapy efficacy indications. The desired final goal would be to have available tools allowing to reduce the recurrence rate, increase both the disease progression free interval and of course the overall survival at five years from the diagnosis that today is still very low.

Systematic review and meta-analysis of studies assessing the relationship between statin use and risk of ovarian cancer

PURPOSE

The link between lipid-stabilizing medications and epithelial ovarian carcinogenesis is incompletely understood. Statins may reduce ovarian cancer risk, but results are inconclusive.

METHODS

We conducted a systematic review and meta-analysis of studies reporting associations between statin use and ovarian cancer risk in PubMed. Summary risk ratios (RRs) and confidence intervals (CIs) were calculated. Subgroup analyses by cancer histotype, statin class (lipo- or hydrophilic) and duration of statin use were conducted. Use of individual statins in populations was assessed to determine population-specific differences in statin types.

RESULTS

Nine studies with 435,237 total women were included (1 randomized controlled trial (RCT); 4 prospective; 4 case-control). Statin use was associated with a reduced risk of ovarian cancer (RR 0.87, 95% CI 0.74-1.03) and risk was significantly reduced in populations with low pravastatin use (RR 0.83, 95% CI 0.70-0.99). Risk estimates varied by statin class (3 studies; lipophilic: RR 0.88, 95% CI 0.69-1.12; hydrophilic: RR 1.06, 95% CI 0.72-1.57) and cancer histotype (3 studies; serous: RR 0.95, 95% CI 0.69-1.30; clear cell: RR 1.17, 95% CI 0.74-1.86). Long-term use was associated with a reduced risk of ovarian cancer (RR 0.77, 95% CI 0.54-1.10) that further reduced when pravastatin use was low (RR 0.68, 95% CI 0.46-1.01). Between-study heterogeneity was high overall and in subgroups (I² > 60%).

CONCLUSION

Statins may be associated with a reduced risk of ovarian cancer, but the effect likely differs by individual statin, duration of use and cancer histotype. Additional well-powered studies are needed to elucidate important subgroup effects.

Association of Anti-Mullerian Hormone, Follicle-Stimulating Hormone, and Inhibin B with Risk of Ovarian Cancer in the Janus Serum Bank

BACKGROUND

Reproductive factors, including parity, breastfeeding, and contraceptive use, affect lifetime ovulatory cycles and cumulative exposure to gonadotropins and are associated with ovarian cancer. To understand the role of ovulation-regulating hormones in the etiology of ovarian cancer, we prospectively analyzed the association of anti-Mullerian hormone (AMH), follicle-stimulating hormone (FSH), and inhibin B with ovarian cancer risk.

METHODS

Our study included 370 women from the Janus Serum Bank, including 54 type I and 82 type II invasive epithelial ovarian cancers, 49 borderline tumors, and 185 age-matched controls. We used conditional logistic regression to assess the relationship between hormones and risk of ovarian cancer overall and by subtype (types I and II).

RESULTS

Inhibin B was associated with increased risk of ovarian cancer overall [OR, 1.97; 95% confidence interval (CI), 1.14-3.39; P trend = 0.05] and with type I ovarian (OR, 3.10; 95% CI, 1.04-9.23; P trend = 0.06). FSH was not associated with ovarian cancer risk overall, but higher FSH was associated with type II ovarian cancers (OR, 2.78; 95% CI, 1.05-7.38). AMH was not associated with ovarian cancer risk.

CONCLUSIONS

FSH and inhibin B may be associated with increased risk in different ovarian cancer subtypes, suggesting that gonadotropin exposure may influence risk of ovarian cancer differently across subtypes.

IMPACT

Associations between prospectively collected AMH, FSH, and inhibin B levels with risk of ovarian cancer provide novel insight on the influence of premenopausal markers of ovarian reserve and gonadotropin signaling. Heterogeneity of inhibin B and FSH effects in different tumor types may be informative of tumor etiology.

Genome-wide Analysis of Common Copy Number Variation and Epithelial Ovarian Cancer Risk

BACKGROUND

Germline DNA copy number variation (CNV) is a ubiquitous source of genetic variation and remains largely unexplored in association with epithelial ovarian cancer (EOC) risk.

METHODS

CNV was quantified in the DNA of approximately 3,500 cases and controls genotyped with the Illumina 610k and HumanOmni2.5M arrays. We performed a genome-wide association study of common (>1%) CNV regions (CNVRs) with EOC and high-grade serous (HGSOC) risk and, using The Cancer Genome Atlas (TCGA), performed in silico analyses of tumor-gene expression.

RESULTS

Three CNVRs were associated (P < 0.01) with EOC risk: two large (∼100 kb) regions within the 610k set and one small (<5 kb) region with the higher resolution 2.5M data. Large CNVRs included a duplication at LILRA6 (OR = 2.57; P = 0.001) and a deletion at CYP2A7 (OR = 1.90; P = 0.007) that were strongly associated with HGSOC risk (OR = 3.02; P = 8.98 × 10^-5). Somatic CYP2A7 alterations correlated with EGLN2 expression in tumors (P = 2.94 × 10^-47). An intronic ERBB4/HER4 deletion was associated with reduced EOC risk (OR = 0.33; P = 9.5 × 10^-2), and somatic deletions correlated with ERBB4 downregulation (P = 7.05 × 10^-5). Five CNVRs were associated with HGSOC, including two reduced-risk deletions: one at 1p36.33 (OR = 0.28; P = 0.001) that correlated with lower CDKIIA expression in TCGA tumors (P = 2.7 × 10^-7), and another at 8p21.2 (OR = 0.52; P = 0.002) that was present somatically where it correlated with lower GNRH1 expression (P = 5.9 × 10^-5).

CONCLUSIONS

Though CNV appears to not contribute largely to EOC susceptibility, a number of low-to-common frequency variants may influence the risk of EOC and tumor-gene expression.

IMPACT

Further research on CNV and EOC susceptibility is warranted, particularly with CNVs estimated from high-density arrays.

Inhibin B suppresses anoikis resistance and migration through the transforming growth factor-β signaling pathway in nasopharyngeal carcinoma

Inhibin B (INHBB), a heterodimer of a common α‐subunit and a βB‐subunit, is a glycoprotein belonging to the transforming growth factor‐β (TGF‐β) family. In this study, we observed INHBB expression was reduced in nasopharyngeal carcinoma (NPC) tissues compared to non‐tumor nasopharyngeal epithelium tissues, and INHBB was associated with lymph node metastasis, stage of disease, and clinical progress. Positive expression of INHBB in NPC predicted a better prognosis (overall survival, P = 0.038). However, the molecular mechanisms of INHBB have not been addressed in NPC. We induced anoikis‐resistant cells in NPC cell lines under anchorage‐independent conditions, then found epithelial‐mesenchymal transition markers changed, cell apoptosis decreased, cell cycle was modified, and invasion strengthened in anoikis‐resistant NPC cells. These anoikis‐resistant NPC cells showed decreased expression of INHBB compared with adhesion cells. Furthermore, INHBB was found to influence the above‐mentioned changes. In the anoikis‐resistant NPC cells with INHBB overexpression, apoptotic cells increased, S phase cells weakened, vimentin, matrix metallopeptidase‐9, and vascular endothelial growth factor A expression were downregulated, and E‐cadherin expression was upregulated, and vice versa in knockdown of INHBB (INHBB shRNA) anoikis‐resistant NPC cells. Diminished INHBB expression could activate the TGF‐β pathway to phosphorylate Smad2/3 and form complexes in the nucleus, which resulted in the above changes. Thus, our results revealed for the first time that INHBB could suppress anoikis resistance and migration of NPC cells by the TGF‐β signaling pathway, decrease p53 overexpression, and could serve as a potential biomarker for NPC metastasis and prognosis as well as a therapeutic application.

Assessment of variation in immunosuppressive pathway genes reveals TGFBR2 to be associated with risk of clear cell ovarian cancer

BACKGROUND

Regulatory T (Treg) cells, a subset of CD4+ T lymphocytes, are mediators of immunosuppression in cancer, and, thus, variants in genes encoding Treg cell immune molecules could be associated with ovarian cancer.

METHODS

In a population of 15,596 epithelial ovarian cancer (EOC) cases and 23,236 controls, we measured genetic associations of 1,351 SNPs in Treg cell pathway genes with odds of ovarian cancer and tested pathway and gene-level associations, overall and by histotype, for the 25 genes, using the admixture likelihood (AML) method. The most significant single SNP associations were tested for correlation with expression levels in 44 ovarian cancer patients.

RESULTS

The most significant global associations for all genes in the pathway were seen in endometrioid ( p = 0.082) and clear cell ( p = 0.083), with the most significant gene level association seen with TGFBR2 ( p = 0.001) and clear cell EOC. Gene associations with histotypes at p < 0.05 included: IL12 ( p = 0.005 and p = 0.008, serous and high-grade serous, respectively), IL8RA ( p = 0.035, endometrioid and mucinous), LGALS1 ( p = 0.03, mucinous), STAT5B ( p = 0.022, clear cell), TGFBR1 ( p = 0.021 endometrioid) and TGFBR2 ( p = 0.017 and p = 0.025, endometrioid and mucinous, respectively).

CONCLUSIONS

Common inherited gene variation in Treg cell pathways shows some evidence of germline genetic contribution to odds of EOC that varies by histologic subtype and may be associated with mRNA expression of immune-complex receptor in EOC patients.

Redefining the origin and evolution of ovarian cancer: a hormonal connection

Ovarian cancer has the highest mortality of all female reproductive cancers. Late diagnosis, tumour heterogeneity and the development of chemoresistance contribute to this statistic and work against patient survival. Current studies have revealed novel concepts that impact our view on how ovarian cancer develops. The greatest impact is on our understanding that, as a disease, ovarian cancer has multiple cellular origins and that these malignant precursors are mostly derived from outside of the ovaries. In this review, we propose a new concept of a step-wise developmental process that may underwrite ovarian tumorigenesis and progression: (1) migration/recruitment to the ovaries; (2) seeding and establishment in the ovaries; (3) induction of a dormant cancer stage; and (4) expansion and tumor progression. We will discuss the relationship of each step with the changing ovarian function and milieu during the reproductive age and the subsequent occurrence of menopause. The realization that ovarian cancer development and progression occurs in distinct steps is critical for the search of adequate markers for early detection that will offer personalized strategies for prevention and therapy.

Docetaxel combined with intraperitoneal hyperthermic perfusion chemotherapy and hyperthermia in the treatment of advanced ovarian cancer

Ovarian cancer is a clinical type of gynecological malignant tumor with poor prognosis and a high mortality rate. At present, the primary treatment method used is surgery, with chemotherapy as an ajdunctive therapy. Thus, new short-term treatments should be identified. The aim of the present study was to investigate the short-term curative effects and safety of docetaxel combined with intraperitoneal cisplatin chemotherapy and hyperthermia treatment of advanced ovarian cancer. A total of 112 cases of advanced (stage III–IV) ovarian cancer patients confirmed by clinical diagnosis between October 2014 and December 2015 were included in the study. The patients were randomly divided into the study and control groups (n=56 cases). The control group was treated with docetaxel and intraperitoneal cisplatin hyperthermic perfusion chemotherapy, while the study group was treated with docetaxel venous chemotherapy and intraperitoneal cisplatin cyclical hyperthermic perfusion chemotherapy with BR-TRG-1 body cavity hyperthermic perfusion treatment system. Clinical treatment results for short-term curative effects and adverse reactions were compared and analyzed 8 weeks after treatment. The total effective rate of the study and control groups were 87.5 and 62.5%, respectively, and the difference was statistically significant (P<0.05). The controlled rate of ascites, remission rate of tumor and descent rate of CA125 of patients in the study group were better than patients in the control group (P<0.05). The rate of adverse reactions of patients in the study group was 39.3%, and the grade of toxicity was from I to II, while the rate of adverse reactions of patients in the control group was 55.4%, and the grade of toxicity was from II to III. The difference between the two groups was statistically significant (P<0.05). In conclusion, applying the combination of docetaxel, intraperitoneal cisplatin hyperthermic perfusion chemotherapy and hyperthermia to treat advanced ovarian cancer can improve the curative effects with little toxicity; thus, it is worthy of promotion and application.

Diabetes mellitus and gynecologic cancer: molecular mechanisms, epidemiological, clinical and prognostic perspectives

INTRODUCTION

Diabetes mellitus, the prevalence of which has increased dramatically worldwide, may put patients at a higher risk of cancer. The aim of our study is the clarification of the possible mechanisms linking diabetes mellitus and gynecological cancer and their epidemiological relationship.

MATERIALS AND METHODS

This is a narrative review of the current literature, following a search on MEDLINE and the Cochrane Library, from their inception until January 2012. Articles investigating gynecologic cancer (endometrial, ovarian, and breast) incidence in diabetic patients were extracted.

RESULTS

The strong evidence for a positive association between diabetes mellitus and the risk for cancer indicates that energy intake in excess to energy expenditure, or the sequelae thereof, is involved in gynecological carcinogenesis. This risk may be further heightened by glucose which can directly promote the production of tumor cells by functioning as a source of energy. Insulin resistance accompanied by secondary hyperinsulinemia is hypothezised to have a mitogenic effect. Steroid hormones are in addition potent regulators of the balance between cellular differentiation, proliferation, and apoptosis. Inflammatory pathways may also be implicated, as a correlation seems to exist between diabetes mellitus and breast or endometrial carcinoma pathogenesis, although an analogous correlation with ovarian carcinoma is still under investigation. Antidiabetic agents have been correlated with elevated cancer risk, while metformin seems to lower the risk.

CONCLUSION

Diabetes mellitus is associated with an elevation in gynecologic cancer risk. Moreover, there are many studies exploring the prognosis of patients with diabetes and gynecological cancer, the outcome and the overall survival in well-regulated patients.