In 2014, can we do better than CA125 in the early detection of ovarian cancer?

Exosome-transmitted miR-30a-5p enhances cell proliferation, migration, and invasion in ovarian cancer

BACKGROUND

Ovarian cancer (OC) causes the highest rates of mortality among women's genital tract malignancies. Micro-ribonucleic acid (miRNA), the most abundant long noncoding RNAs transmitted by exosomes, has been revealed to be a potential marker for OC since 2008. In this study, we aimed to determine the possible roles of miRNAs derived from exosomes in the early diagnosis of OC through miRNA microarray, besides, exploring the underlying mechanisms of miRNAs in the OC progression.

METHODS

We isolated exosomes from high invasive OC cell line HO8910PM and its parent cell line HO8910 using transmission electron microscopy and western blot, and performed miRNA microarray to identify the exosome-transmitted miRNA from the two cell lines, respectively. The expression profile was obtained by quantitative analysis, and then the differentially expressed individuals were screened. miRNA-30a-5p, a stable miRNA in both cells of our sequencing data was set for further study. MiR-30a-5p mimics, inhibitor and their corresponding negative controls were applied in OC cells. Then the cell proliferation, migration, and invasion of different groups were analyzed via cell counting-kit 8 (CCK8), wound healing, and Transwell analyses. Besides, ZBE2 and LDH2 expressions were detected by qRT-PCR.

RESULTS

Combined with the data report of miRNA microarray technology, we set miR-30a-5p as our target miRNA to analyze its molecular function in regulating proliferation, migration, and invasion in OC cells. Our results showed that the miR-30a-5p overexpression could significantly enhance the capability of proliferation, migration, and invasion of HO8910 and HO8910PM cells, whereas the miR-30a-5p inhibition showed the opposite tendency (all P < 0.05). Besides, miR-30a-5p may be involved in these oncogenic processes through the upregulation of ZEB2 and LDH2.

CONCLUSION

Our results demonstrate that exosome-transmitted miRNA-30a-5p promotes the malignant behavior of OC cells, which may be served as a promising diagnostic and prognostic marker for patients with OC.

Engineering of a Fully Human Anti-MUC-16 Antibody and Evaluation as a PET Imaging Agent

Antibodies that recognize cancer biomarkers, such as MUC16, can be used as vehicles to deliver contrast agents (imaging) or cytotoxic payloads (therapy) to the site of tumors. MUC16 is overexpressed in 80% of epithelial ovarian cancer (EOC) and 65% of pancreatic ductal adenocarcinomas (PDAC), where effective ‘theranostic’ probes are much needed. This work aims to develop fully human antibodies against MUC16 and evaluate them as potential immuno-PET imaging probes for detecting ovarian and pancreatic cancers. We developed a fully human monoclonal antibody, M16Ab, against MUC16 using phage display. M16Ab was conjugated with p-SCN-Bn-DFO and radiolabeled with 89Zr. 89Zr-DFO-M16Ab was then evaluated for binding specificity and affinity using flow cytometry. In vivo evaluation of 89Zr-DFO-M16Ab was performed by microPET/CT imaging at different time points at 24−120 h post injection (p.i.) and ex vivo biodistribution studies in mice bearing MUC16-expressing OVCAR3, SKOV3 (ovarian) and SW1990 (pancreatic) xenografts. 89Zr-DFO-M16Ab bound specifically to MUC16-expressing cancer cells with an EC50 of 10nM. 89Zr-DFO-M16Ab was stable in serum and showed specific uptake and retention in tumor xenografts even after 120 h p.i. (microPET/CT) with tumor-to-blood ratios > 43 for the SW1990 xenograft. Specific tumor uptake was observed for SW1990/OVCAR3 xenografts but not in MUC16-negative SKOV3 xenografts. Pharmacokinetic study shows a relatively short distribution (t1/2α) and elimination half-life (t1/2ß) of 4.4 h and 99 h, respectively. In summary, 89Zr-DFO-M16Ab is an effective non-invasive imaging probe for ovarian and pancreatic cancers and shows promise for further development of theranostic radiopharmaceuticals.

The International Ovarian Tumor Analysis-Assessment of Different Neoplasias in the Adnexa (IOTA-ADNEX) Model Assessment for Risk of Ovarian Malignancy in Adnexal Masses

Ovarian cancers are one of the major leading causes of death across the world. In addition to many challenges to diagnose the disease, it is also hard to predict the type of cancer with effective tools and technology. Many attempts have been made to diagnose ovarian malignancies using ultrasonography, MRI, and CT scans, but seldom will they give the clinician a clear understanding of cancer's type and stage. It is of utmost importance to understand the mass peri-operatively, which will help the clinicians to decide on the course of management mortality. With technological advancements, many predictive models have come into the picture. Many of those were dependent on the Serum CA-125 markers. With ultrasonography machine usage, the International Ovarian Tumor Analysis (IOTA) group has developed a Simple Rules model, Logistic Regression (LR) models, and, most recently, the IOTA-assessment of different neoplasias in the adnexa (IOTA-ADNEX) model. It has been found to be effective and reliable among all the tools developed in the past. The ADNEX predicts the type of cancer (benign or malignant) and stages of cancer (borderline, Stage I, Stages II-IV, and secondary metastatic). These models can be used for people who are coming with persistent adnexal masses in the ovarian region, para ovarian region, or in the tubes and are recommended for the surgeries. The model is developed by a team of clinicians and statisticians, based on ultrasound and clinical data. This article reviews the IOTA-ADNEX model as a tool for predicting ovarian malignancies in people coming with adnexal masses, especially in comparison with other methods and models. It also tests its effectiveness in the hands of experienced technicians and non-expert technicians.

Effect of Serum Level of Human Epididymis Protein 4 and Interleukin-6 as Biomarkers in Patients with Adnexal Mass

Ovarian carcinoma is one of the most common types of neoplasms in women and the fifth leading cause of cancer death among women worldwide. Adnexal masses are classified as simple or complicated and can be benign or malignant. No single biomarker has demonstrated high sensitivity and specificity for detecting early ovarian cancer. Therefore, the current study was designed to investigate the influence of using two biomarkers as a tool for diagnosis in patients with an adnexal mass. This prospective case-control study was carried out on female patients diagnosed by ultrasound and magnetic resonance imaging with adnexal masses and scheduled for surgery and healthy women as a control group (n=50 each). The patients were in the age range of 16-80 years old and had attended the surgical rooms of Basrah hospitals, Basrah, Iraq, from January to July 2021. The levels of serum biomarkers were quantitatively assessed using the enzyme-linked immunosorbent assay. The serum concentration of the human epididymis protein 4 (HE4) biomarker exhibited significant differences between females with adnexal mass and healthy women. There was no significant association between neither the patient's age nor the menopausal state and the serum level of HE4. The serum level of HE4 had a sensitivity of 92% and a specificity of 66% as a serum marker for the presence of adnexal mass with a positive predictive value of 73% and a negative predictive value of 89%. In this study, serum interleukin-6 (IL-6) had a sensitivity of 30% and specificity of 64% in determining patients with adnexal mass pathology. It was found that the level of IL-6 was similar in all patients, compared to that in the control group. The median levels of serum HE4 showed high value in patients in the age groups of 21-40, 41-50, and >50 than in the control group; however, it was not statistically different (P=0.413). Human epididymis protein 4 was the top biomarker representing a higher concentration in adnexal mass; moreover, it demonstrated the highest performance in all samples with Adnexal mass. The results of our study showed that combining more than one marker measurement increased both the sensitivity and specificity of distinguishing patients with adnexal mass pathology.

Prospective evaluation of 92 serum protein biomarkers for early detection of ovarian cancer

BACKGROUND

CA125 is the best available yet insufficiently sensitive biomarker for early detection of ovarian cancer. There is a need to identify novel biomarkers, which individually or in combination with CA125 can achieve adequate sensitivity and specificity for the detection of earlier-stage ovarian cancer.

METHODS

In the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, we measured serum levels of 92 preselected proteins for 91 women who had blood sampled ≤18 months prior to ovarian cancer diagnosis, and 182 matched controls. We evaluated the discriminatory performance of the proteins as potential early diagnostic biomarkers of ovarian cancer.

RESULTS

Nine of the 92 markers; CA125, HE4, FOLR1, KLK11, WISP1, MDK, CXCL13, MSLN and ADAM8 showed an area under the ROC curve (AUC) of ≥0.70 for discriminating between women diagnosed with ovarian cancer and women who remained cancer-free. All, except ADAM8, had shown at least equal discrimination in previous case-control comparisons. The discrimination of the biomarkers, however, was low for the lag-time of >9-18 months and paired combinations of CA125 with any of the 8 markers did not improve discrimination compared to CA125 alone.

CONCLUSION

Using pre-diagnostic serum samples, this study identified markers with good discrimination for the lag-time of 0-9 months. However, the discrimination was low in blood samples collected more than 9 months prior to diagnosis, and none of the markers showed major improvement in discrimination when added to CA125.

Diagnostic performance of microRNA-34a, let-7f and microRNA-31 in epithelial ovarian cancer prediction

Objective

To correlate the genome-wide methylation signature of microRNA genes with dysregulated expression of selected candidate microRNA in tissue and serum samples of epithelial ovarian cancer (EOC) and control using quantitative reverse transcription polymerase chain reaction (qRT-PCR), and evaluation of EOC predictive value of candidate microRNA at an early stage.

Methods

We performed Methylated DNA Immunoprecipitation coupled with NGS (MeDIP-NGS) sequencing of 6 EOC and 2 normal tissue samples of the ovary. Expression of selected microRNA from tissue (EOC=85, normal=30) and serum (EOC=50, normal=15) samples was evaluated using qRT-PCR. We conducted bioinformatics analysis to identify the candidate miRNA’s potential target and functional role.

Results

MeDIP-NGS sequencing revealed hypermethylation of several microRNAs gene promoters. Three candidate microRNAs were selected (microRNA-34a, let-7f, and microRNA-31) from MeDIP-NGS data analysis based on log2FC and P-value. The relative expression level of microRNA-34a, let-7f, and microRNA-31 was found to be significantly reduced in early-stage EOC tissues and serum samples (p<0.0001). The receiver operating characteristic analysis of microRNA-34a, let-7f and miR-31 showed improved diagnostic value with area under curve(AUC) of 92.0 (p<0.0001), 87.9 (p<0.0001), and 85.6 (p<0.0001) and AUC of 82.7 (p<0.0001), 82.0 (p<0.0001), and 81.0 (p<0.0001) in stage III-IV and stage I-II EOC serum samples respectively. The integrated diagnostic performance of microRNA panel (microRNA-34a+let-7f+microRNA-31) in late-stage and early-stage serum samples was 95.5 and 96.9 respectively.

Conclusion

Our data correlated hypermethylation-associated downregulation of microRNA in EOC. In addition, a combined microRNA panel from serum could predict the risk of EOC with greater AUC, sensitivity, and specificity.

miR-34a, let-7f, and miR-31 promoters were significantly methylated in EOC samples. Significant reduced level of miR-34a, miR-31 and let-7f was observed in EOC samples. Individual and combined miRNA panel have higher diagnostic value for EOC prediction. miR-34a, let-7f and miR-31 can discriminate metastatic over non-metastatic samples.

Biomarkers in Ovarian Pathology: From Screening to Diagnosis. Review of the Literature

Background: Ovarian cancer has a low incidence, but high mortality due to a habitual diagnosis in advanced cancer stages. Currently, used biomarkers have good sensitivity, but low specificity. Aim: To determine the usefulness of the biomarkers and algorithms used up to now in the screening, diagnosis, response to treatments and identification of recurrence in patients with ovarian masses. Methodology: Systematic search of publications in English in the Medline-PubMed database with the terms: “biomarkers”, “tumour”, “tumour biomarkers”, “marker”, “tumour marker”, “ovarian cancer”, “ovarian”, “Neoplasms”, “cancer”, CA-125 Antigen; Human Epididymis-specific Protein E4; Risk of Malignancy Index (RMI); Risk of Ovarian Malignancy Algorithm (ROMA); Ovarian Neoplasms. Original articles, clinical trials, reviews, systematic reviews and meta-analyses, published between January 2000 and November 2020, were selected to determine the usefulness (among others) of CA 125 and HE4 antigen in ovarian cancer. Results: Finally, 39 transcendental publications were selected to write this article to determine the usefulness of tumour markers and algorithms in ovarian cancer. Conclusions: The usefulness of the tumour markers antigen CA125 and antigen HE4 individually or as a basis for decision-making algorithms has low specificity; however, there is little evidence that confirms their usefulness as markers in ovarian cancer screening.

Extracellular Vesicle Transmission of Chemoresistance to Ovarian Cancer Cells Is Associated with Hypoxia-Induced Expression of Glycolytic Pathway Proteins, and Prediction of Epithelial Ovarian Cancer Disease Recurrence

Simple Summary

Ovarian cancer is one of the most lethal cancers affecting women worldwide. Its high mortality rate is often attributed to the non-specific nature of early symptoms of the disease. Developing a better understanding of the disease progression and identifying clinically useful biomarkers that aid in clinical management are requisite to reducing the mortality rate of ovarian cancer. Reduced oxygen tension (i.e., hypoxia) is not only a characteristic of solid tumors but may also enhance the metastatic capacity of tumors by inducing the release of tumor growth promoting factors. Recently, it has been proposed that small tumor-derived extracellular vesicles (sEVs) facilitate cancer progression. In this study, we established that sEVs produced under low oxygen tension induce a metabolic switch in ovarian cancer cells associated with changes in glycolytic pathway proteins that promote resistance to carboplatin. Significantly, we identified a suite of sEV-associated glycolysis pathway proteins that are present in patients with ovarian cancer that can predict disease recurrence with over 90% accuracy.

Abstract

Hypoxia is a key regulator of cancer progression and chemoresistance. Ambiguity remains about how cancer cells adapt to hypoxic microenvironments and transfer oncogenic factors to surrounding cells. In this study, we determined the effects of hypoxia on the bioactivity of sEVs in a panel of ovarian cancer (OvCar) cell lines. The data obtained demonstrate a varying degree of platinum resistance induced in OvCar cells when exposed to low oxygen tension (1% oxygen). Using quantitative mass spectrometry (Sequential Window Acquisition of All Theoretical Fragment Ion Mass Spectra, SWATH) and targeted multiple reaction monitoring (MRM), we identified a suite of proteins associated with glycolysis that change under hypoxic conditions in cells and sEVs. Interestingly, we identified a differential response to hypoxia in the OvCar cell lines and their secreted sEVs, highlighting the cells’ heterogeneity. Proteins are involved in metabolic reprogramming such as glycolysis, including putative hexokinase (HK), UDP-glucuronosyltransferase 1–6 (UD16), and 6-phosphogluconolactonase (6 PGL), and their presence correlates with the induction of platinum resistance. Furthermore, when normoxic cells were exposed to sEVs from hypoxic cells, platinum-resistance increased significantly (p < 0.05). Altered chemoresistance was associated with changes in glycolysis and fatty acid synthesis. Finally, sEVs isolated from a clinical cohort (n = 31) were also found to be enriched in glycolysis-pathway proteins, especially in patients with recurrent disease. These data support the hypothesis that hypoxia induces changes in sEVs composition and bioactivity that confers carboplatin resistance on target cells. Furthermore, we propose that the expression of sEV-associated glycolysis-pathway proteins is predictive of ovarian cancer recurrence and is of clinical utility in disease management.

Reducing Ovarian Cancer Mortality Through Early Detection: Approaches Using Circulating Biomarkers

More than two-thirds of all women diagnosed with epithelial ovarian cancer (EOC) will die from the disease (>14,000 deaths annually), a fact that has not changed considerably in the last three decades. Although the 5-year survival rates for most other solid tumors have improved steadily, ovarian cancer remains an exception, making it the deadliest of all gynecologic cancers and five times deadlier than breast cancer. When diagnosed early, treatment is more effective, with a 5-year survival rate of up to 90%. Unfortunately, most cases are not detected until after the cancer has spread, resulting in a dismal 5-year survival rate of less than 30%. Current screening methods for ovarian cancer typically use a combination of a pelvic examination, transvaginal ultrasonography, and serum cancer antigen 125 (CA125), but these have made minimal impact on improving mortality. Thus, there is a compelling unmet need to develop new molecular tools that can be used to diagnose early-stage EOC and/or assist in the clinical management of the disease after a diagnosis, given that more than 220,000 women are living with ovarian cancer in the United States and are at risk of recurrence. Here, we discuss the state of advancing liquid-based approaches for improving the early detection of ovarian cancer.See all articles in this Special Collection Honoring Paul F. Engstrom, MD, Champion of Cancer Prevention.

Value of Growth/Differentiation Factor 15 in Diagnosis and the Evaluation of Chemotherapeutic Response in Lung Cancer

PURPOSE

There is a need for efficient, convenient, and inexpensive methods to accurately diagnose the clinical stage of lung cancer and evaluate the efficacy of chemotherapy in patients with lung cancer. Although growth/differentiation factor 15 (GDF)-15 has great potential as a tumor marker, supporting clinical evidence is still lacking. In this study, we aimed to analyze the relationship between serum GDF15 concentration and the clinical characteristics of patients with lung cancer, and to assess the value of GDF15 in the diagnosis and curative effect of chemotherapy.

METHODS

The study comprised 160 participants in total, of whom 88 had lung cancer, 31 had pneumonia, and 41 were control subjects. Among the 88 patients with lung cancer, 64 were willing to participate in follow-up chemotherapy-related studies and meet the inclusion criteria. The serum GDF15 concentration in 288 samples (31 cases, pneumonia group samples; 41 cases, control samples; 88 cases, lung cancer group samples; 64 cases, after 1 chemotherapy cycle; and 64 cases, after 2 chemotherapy cycles) with advanced lung cancer were detected by ELISA. The possible correlations between serum GDF15 level and sex, age, height, weight, body mass index, smoking history, diabetes status, and laboratory findings (hemoglobin, prealbumin, and lactate dehydrogenase) were analyzed using parametric and nonparametric tests. Thereafter, the sensitivity of GDF15 in diagnosing lung cancer was calculated. The serum levels of GDF15, carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and cytokeratin 19 fragment (CYFRA) 21-1 were determined in 64 patients with lung cancer, before and after chemotherapy reception. For the evaluation of the efficacy of chemotherapy, receiver operating characteristic curves were plotted.

FINDINGS

Serum GDF15 concentration at baseline was significantly higher in the lung cancer group than were those in the pneumonia and control groups (both, P < 0.001). An increased expression of serum GDF15 was significantly correlated with diabetes, anemia, and clinical stage (tumor size, nodal involvement, and presence/absence of metastasis). After 2 cycles of chemotherapy among the 64 patients who received it, serum GDF15 concentrations were significantly different from baseline in those who had progressive disease (P = 0.003), stable disease (P < 0.001), or partial response (P = 0.039). The AUC of GDF15 was greater than those of CEA, NSE, and CYFRA 21-1 (0.851 vs 0.630, 0.720, and 0.654, respectively).

IMPLICATIONS

GDF15 is complementary to CEA, NSE, and CYFRA 21-1 in diagnosing lung cancer and, when used in combination, it could be of great diagnostic value and may facilitate correct predictions of the efficacy of chemotherapy. Therefore, serum GDF15 concentration is valuable in lung cancer diagnosis and in the evaluation of the efficacy of chemotherapy.

SPOCD1 accelerates ovarian cancer progression and inhibits cell apoptosis via the PI3K/AKT pathway

Background

Ovarian cancer (OC) is the most common type of gynecological malignant tumors with poor prognosis. The spen paralogue and orthologue C-terminal domain containing 1 (SPOCD1) is a newly identified molecule that has been indicated to discriminate progressive in human solid tumors. However, the role of SPOCD1 in OC remains unknown.

Methods

The expression of SPOCD1 in OC and non-cancerous tissue was detected by Realtime polymerase chain reaction and immunohistochemical staining. The expression of SPOCD1 in OC cells (SKOV3 and CAOV3) was also detected by immunohistochemical staining. The effect of SPOCD1 on cell proliferation was analyzed by Cell Counting Kit 8 and colony formation assay, and cell migration was analyzed by transwell assay. Apoptosis was analyzed by flow cytometry. The protein expression of SPOCD1, PTEN, PI3K, p-AKT, and mTOR in OC cells was measured by Western blot.

Results

SPOCD1 expression was significantly upregulated in OC tissues compared with non-cancerous tissues (P<0.01), and was positively correlated to FIGO stage and tumor grade of OC. Also, SPOCD1 was significantly expressed in nucleus and cytoplasm of SKOV3 and CAOV3 cells. Kaplan–Meier analysis indicated that patients with high SPOCD1 expression had shorter overall survival (HR =1.512, 95%CI: 1.321–2.793, P=0.031) and progression-free survival (HR =1.875, 95%CI: 1.435–3.157, P=0.028). SPOCD1 was upregulated in OC SKOV3 and CAOV3 cells. Further investigation revealed that downregulation of SPOCD1 inhibited the SKOV3 and CAOV3 cells proliferation and migration. In addition, the deficit of SPOCD1 increased the apoptosis in SKOV3 and CAOV3 cells. PI3K/AKT pathway was inhibited by knockdown of SPOCD1 in SKOV3 and CAOV3 cells.

Conclusions

Our data suggest that SPOCD1 may act as a carcinogenesis factor by activating the PI3K/AKT pathway to restrained cell apoptosis in OC.

Ovarian Cancer Biomarkers: Moving Forward in Early Detection

Ovarian cancer is a silent cancer which rate survival mainly relays in early stage detection. The discovery of reliable ovarian cancer biomarkers plays a crucial role in the disease management and strongly impact in patient's prognosis and survival. Although having many limitations CA125 is a classical ovarian cancer biomarker, but current research using proteomic or metabolomic methodologies struggles to find alternative biomarkers, using non-invasive our relatively non-invasive sources such as urine, serum, plasma, tissue, ascites or exosomes. Metabolism and metabolites are key players in cancer biology and its importance in biomarkers discovery cannot be neglected. In this chapter we overview the state of art and the challenges facing the use and discovery of biomarkers and focus on ovarian cancer early detection.

An Improved Prediction Model for Ovarian Cancer Using Urinary Biomarkers and a Novel Validation Strategy

This study was designed to analyze urinary proteins associated with ovarian cancer (OC) and investigate the potential urinary biomarker panel to predict malignancy in women with pelvic masses. We analyzed 23 biomarkers in urine samples obtained from 295 patients with pelvic masses scheduled for surgery. The concentration of urinary biomarkers was quantitatively assessed by the xMAP bead-based multiplexed immunoassay. To identify the performance of each biomarker in predicting cancer over benign tumors, we used a repeated leave-group-out cross-validation strategy. The prediction models using multimarkers were evaluated to develop a urinary ovarian cancer panel. After the exclusion of 12 borderline tumors, the urinary concentration of 17 biomarkers exhibited significant differences between 158 OCs and 125 benign tumors. Human epididymis protein 4 (HE4), vascular cell adhesion molecule (VCAM), and transthyretin (TTR) were the top three biomarkers representing a higher concentration in OC. HE4 demonstrated the highest performance in all samples with OC (mean area under the receiver operating characteristic curve (AUC) 0.822, 95% CI: 0.772–0.869), whereas TTR showed the highest efficacy in early-stage OC (AUC 0.789, 95% CI: 0.714–0.856). Overall, HE4 was the most informative biomarker, followed by creatinine, carcinoembryonic antigen (CEA), neural cell adhesion molecule (NCAM), and TTR using the least absolute shrinkage and selection operator (LASSO) regression models. A multimarker panel consisting of HE4, creatinine, CEA, and TTR presented the best performance with 93.7% sensitivity (SN) at 70.6% specificity (SP) to predict OC over the benign tumor. This panel performed well regardless of disease status and demonstrated an improved performance by including menopausal status. In conclusion, the urinary biomarker panel with HE4, creatinine, CEA, and TTR provided promising efficacy in predicting OC over benign tumors in women with pelvic masses. It was also a non-invasive and easily available diagnostic tool.

Tumor markers: myths and facts unfolded

OBJECTIVE

The purpose of this article is to review the most commonly used tumor markers in abdominal and pelvic tumors, describe their limitations and explain how to use them in the context of known cancer in order to optimize multidisciplinary care of oncologic patients.

CONCLUSION

Tumor markers are important for the diagnosis, staging, monitoring of treatment and detection of recurrence in many cancers. This knowledge is crucial in the daily interpretation of images of oncologic and non-oncologic patients. However, radiologists should also be aware of the limitations of the most commonly used tumor markers and they should not be used solely, but interpreted in conjunction with diagnostic imaging, clinical history and physical examination that will help optimize the multidisciplinary care and management of oncologic patients.

The contribution and perspectives of proteomics to uncover ovarian cancer tumor markers

Despite all the advances in understanding the mechanisms involved in ovarian cancer (OC) development, many aspects still need to be unraveled and understood. Tumor markers (TMs) are of special interest in this disease. Some aspects of clinical management of OC might be improved by the use of validated TMs, such as differentiating subtypes, defining the most appropriate treatment, monitoring the course of the disease, or predicting clinical outcome. The Food and Drug Administration (FDA) has approved a few TMs for OC: CA125 (cancer antigen 125; monitoring), HE4 (Human epididymis protein; monitoring), ROMA (Risk Of Malignancy Algorithm; HE4+CA125; prediction of malignancy) and OVA1 (Vermillion's first-generation Multivariate Index Assay [MIA]; prediction of malignancy). Proteomics can help advance the research in the field of TMs for OC. A variety of biological materials are being used in proteomic analysis, among them tumor tissues, interstitial fluids, tumor fluids, ascites, plasma, and ovarian cancer cell lines. However, the discovery and validation of new TMs for OC is still very challenging. The enormous heterogeneity of histological types of samples and the individual variability of patients (lifestyle, comorbidities, drug use, and family history) are difficult to overcome in research protocols. In this work, we sought to gather relevant information regarding TMs, OC, biological samples for proteomic analysis, as well as markers and algorithms approved by the FDA for use in clinical routine.

A review of the effects of healthcare disparities on the experience and survival of ovarian cancer patients of different racial and ethnic backgrounds

Ovarian cancer (OC) is a serious condition that often presents at advanced stages and has high mortality rates, with the current mode of early-stage screening lacking sensitivity and specificity. OC often presents asymptomatically, which renders early diagnosis difficult. Furthermore, many patients lack significant risk factors or family history of the disease. Five-year survival rates differ between patients with OC among racial, ethnic, and social groups as a result of different social barriers. This review article aims to present the currently existing data regarding health care disparities among OC patients of different ethnic, demographic, and socioeconomic backgrounds, and what next steps should be taken to better understand and eventually eliminate these potentially devastating health care disparities. Increasing data support the notion that a combination of genomic, socioeconomic status, social factors, and cultural differences lead to differential treatments and therefore health care disparities. While genomic and biological factors are important, language barriers, geographic and travel barriers, differences in comorbidity likelihood between populations, and different treatment plans seem to have a greater impact on 5-year survival rates of patients from diverse backgrounds. Language barriers limit a shared-decision model of care. Transportation limitations and geographic differences can lead to limited follow-up and insufficient care in resource and equipment restrictive settings. Patients with these barriers also tend to have a higher incidence of comorbidities that raise the mortality rate of OC. Further research needs to explore effective solutions to bridge health care disparities and understand why they occur.

CHI3L1 results in poor outcome of ovarian cancer by promoting properties of stem-like cells

The role of chitinase-3-like protein 1 (CHI3L1) in ovarian cancer and the possible mechanisms were elucidated. CHI3L1 is a secreted glycoprotein and associated with inflammation, fibrosis, asthma, extracellular tissue remodeling and solid tumors. Our previous study showed CHI3L1 could be a potential prognostic biomarker for epithelial ovarian cancer and could protect cancer cells from apoptosis. Therefore, clinical data and quantitation of CHI3L1 of ovarian cancer patients, tumor spheroid formation, side-population assays, Aldefluor and apoptotic assays, ELISA, RT-PCR, immunoblotting and animal experiments were performed in two ovarian cancer cells lines, OVCAR3 and CA5171, and their CHI3L1-overexpressing and -knockdown transfectants. High expression of CHI3L1 was associated with poor outcome and chemoresistance in ovarian cancer patients. The mRNA expression of CHI3L1 in CA5171 ovarian cancer stem-like cells was 3-fold higher than in CA5171 parental cells. CHI3L1 promoted the properties of ovarian cancer stem-like cells including generating more and larger tumor spheroids and a higher percentage of ALDH+ in tumor cells and promoting resistance to cytotoxic drug-induced apoptosis. CHI3L1 could induce both the Akt (essential) and Erk signaling pathways, and then enhance expression of β-catenin followed by SOX2, and finally promote tumor spheroid formation and other properties of ovarian cancer stem-like cells. OVCAR3 CHI3L1-overexpressing transfectants were more tumorigenic in vivo, whereas CA5171 CHI3L1-knockdown transfectants were not tumorigenic in vivo. CHI3L1 critically enhances the properties of ovarian cancer stem-like cells. CHI3L1 or CHI3L1-regulated signaling pathways and molecules could be potential therapeutic targets in ovarian cancer.

Protein tyrosine phosphatase L1 inhibits high-grade serous ovarian carcinoma progression by targeting IκBα

Background

High-grade serous ovarian cancer (HGSOC) represents most of the ovarian cancers and accounts for 70%-80 % of related deaths. The overall survival of HGSOC has not been remarkably improved in the past decades, due to the tumor dissemination in peritoneal cavity and invasion of adjacent organs. Therefore, identifying molecular biomarkers is invaluable in helping predicting clinical outcomes and developing targeted chemotherapies. Although there have been studies revealing the prognostic significance of protein tyrosine phosphatase L1 (PTPL1) in breast cancer and lung cancer, its involvement and functions in HGSOC remains to be elucidated.

Methods

We retrospectively enrolled a cohort of HGSOC patients after surgical resection. And analyzed the mRNA and protein levels of PTPL1 in tissue samples.

Results

We found that PTPL1 presented a lower expression in HGSOC tissues than in adjacent normal ovarian tissues. Besides, the PTPL1 level was negatively correlated with tumor stage, implying its potential role as a tumor suppressor. Univariate and multivariate analyses identified that patients with higher PTPL1 showed a better overall survival compared to those with lower PTPL1 expression. In addition, cellular experiments confirmed the role of PTPL1 in suppressing tumor proliferation and invasion. Furthermore, we demonstrated that PTPL1 negatively regulated phosphorylation of tyrosine 42 on IκBα (IκBα-pY42). To our knowledge, this is the initial finding on PTPL1 targeting IκBα-pY42 site. Finally, our data indicated that PTPL1 suppressed tumor progression by dephosphorylating IκBα-pY42, which stabilized IκBα and attenuated nucleus translocation of NF-κB.

Conclusion

Our study revealed a tumor-suppressing role of PTPL1 in HGSOC by targeting IκBα.

Tumor-associated autoantibodies as early detection markers for ovarian cancer? A prospective evaluation

Immuno-proteomic screening has identified several tumor-associated autoantibodies (AAb) that may have diagnostic capacity for invasive epithelial ovarian cancer, with AAbs to P53 proteins and cancer-testis antigens (CTAGs) as prominent examples. However, the early detection potential of these AAbs has been insufficiently explored in prospective studies. We performed ELISA measurements of AAbs to CTAG1A, CTAG2, P53 and NUDT11 proteins, for 194 patients with ovarian cancer and 705 matched controls from the European EPIC cohort, using serum samples collected up to 36 months prior to diagnosis under usual care. CA125 was measured using electrochemo-luminiscence. Diagnostic discrimination statistics were calculated by strata of lead-time between blood collection and diagnosis. With lead times ≤6 months, ovarian cancer detection sensitivity at 0.98 specificity (SE98) varied from 0.19 [95% CI 0.08-0.40] for CTAG1A, CTAG2 and NUDT1 to 0.23 [0.10-0.44] for P53 (0.33 [0.11-0.68] for high-grade serous tumors). However, at longer lead-times, the ability of these AAb markers to distinguish future ovarian cancer cases from controls declined rapidly; at lead times >1 year, SE98 estimates were close to zero (all invasive cases, range: 0.01-0.11). Compared to CA125 alone, combined logistic regression scores of AAbs and CA125 did not improve detection sensitivity at equal level of specificity. The added value of these selected AAbs as markers for ovarian cancer beyond CA125 for early detection is therefore limited.

Overexpression of Pyruvate Kinase Type M2 (PKM2) Promotes Ovarian Cancer Cell Growth and Survival Via Regulation of Cell Cycle Progression Related with Upregulated CCND1 and Downregulated CDKN1A Expression

BACKGROUND Many findings have shown that pyruvate kinase type M2 (PKM2) plays crucial roles in regulating the occurrence and development of various human cancers; however, its roles in ovarian cancer oncogenesis remain to be determined. MATERIAL AND METHODS The expression intensity of PKM2 in ovarian cancer tissues was examined by immunohistochemistry (IHC), and was then correlated to patient clinicopathologic characteristics. The roles of PKM2 in ovarian cancer cell proliferation, growth, and survival were examined by CCK-8, colony forming, and flow cytometry assays. The potentially involved molecular were then investigated by Western blot analysis. RESULTS IHC results showed that PKM2 was overexpressed in 100 of 114 (87.7%) serous ovarian cancer tissues as compared with 50 cases of non-cancerous ovarian tissues, and was associated with tumor size ≥7.5 cm and <7.5 cm (p<0.05). Overexpression of PKM2 in SKOV3 and HEY ovarian cancer cells by transfection with PKM2 lentivirus vector led to increased cell proliferation, growth, and survival, which may be related with PKM2 being able to increase cell cycle progress: G1 stage decreased, whereas S stage significantly increased. In contrast, all functions of SKOV3 and HEY cells described above were reversed by knocked down PKM2 expression using siRNA. Further data showed that overexpressed PKM2 led to increased CCND1 and decreased CDKN1A expression, whereas underexpressed PKM2 led to decreased CCND1 and increased CDKN1A expression in ovarian cancer cells. CONCLUSIONS PKM2 may play important roles in ovarian cancer development and may be a treatment target for this cancer.

AKT2 contributes to increase ovarian cancer cell migration and invasion through the AKT2-PKM2-STAT3/NF-κB axis

Multiple studies have shown that protein kinase Bβ (AKT2) is involved in the development and progression of ovarian cancer, however, its precise role remains unclear. Here we explored the underlying molecular mechanisms how AKT2 promotes ovarian cancer progression. We examined the effects of AKT2 in vitro in two ovarian cancer cell lines (SKOV3 and HEY), and in vivo by metastasis assay in nude mice. The migration and invasion ability of SKOV3 and HEY cells was determined by transwell assay. Overexpression and knockdown (with shRNA) experiments were carried out to unravel the underlying signaling mechanisms induced by AKT2. Overexpression of AKT2 led to increased expression of pyruvate kinase (PKM2) in ovarian cancer cells and in lung metastatic foci from nude mice. Elevated AKT2/PKM2 expression induced cell migration and invasion in vitro, as well as lung metastasis in vivo; silencing AKT2 blocked these effects. Meanwhile, PKM2 overexpression was unable to increase AKT2 expression. The expressions of p-PI3K, p-AKT2, and PKM2 were increased when stimulated by epidermal growth factor (EGF); however, these expressions were blocked when inhibited the PI3K by LY294002. STAT3 expression was elevated and NF-κB p65 nuclear translocation was activated both in vitro and in vivo when either AKT2 or PKM2 was overexpressed; and these effects were inhibited when silencing AKT2 expression. Taken together, AKT2 increases the migration and invasion of ovarian cancer cells in vitro and promotes lung metastasis in nude mice in vivo through PKM2-mediated elevation of STAT3 expression and NF-κB activation. In conclusion, we highlight a novel mechanism of the AKT2-PKM2-STAT3/NF-κB axis in the regulation of ovarian cancer progression, and our work suggested that both AKT2 and PKM2 may be potential targets for the treatment of ovarian cancer.

Does the Risk of Ovarian Malignancy Algorithm Provide Better Diagnostic Performance Than HE4 and CA125 in the Presurgical Differentiation of Adnexal Tumors in Polish Women?

Aim

This study compared the diagnostic performance of the Risk of Ovarian Malignancy Algorithm (ROMA) and HE4 and CA125 for the presurgical differentiation of adnexal tumors.

Material and Methods

This prospective study included 302 patients admitted for surgical treatment due to adnexal tumors. The ROMA was calculated depending on CA125, HE4, and menopausal status.

Results

Fifty patients were diagnosed with malignant disease. In the differentiation of malignant from nonmalignant adnexal tumors, the area under curve (AUC) was higher for ROMA and HE4 than that for CA125 in both the premenopausal and postmenopausal subgroups. In the differentiation of stage I FIGO malignancies and epithelial ovarian cancer from nonmalignant pathologies, the AUC of HE4 and ROMA was higher than that of CA125. The ROMA performed significantly better than CA125 in the differentiation of all malignancies and differentiation of stage I FIGO malignancies from nonmalignant pathologies (p = 0.043 and p = 0.025, resp.). There were no significant differences between the ROMA and the tumor markers for any other variants.

Conclusions

The ROMA is more useful than CA125 for the differentiation of malignant (including stage I FIGO) from nonmalignant adnexal tumors. It is also as useful as HE4 and CA125 for the differentiation of epithelial ovarian cancer from nonmalignant adnexal tumors.

Lycopene Protects Against Spontaneous Ovarian Cancer Formation in Laying Hens

Background

Dietary intake of lycopene has been associated with a reduced risk of ovarian cancer, suggesting its chemopreventive potential against ovarian carcinogenesis. Lycopene's molecular mechanisms of action in ovarian cancer have not been fully understood. Therefore, in the present study, we investigated the effects of lycopene on the ovarian cancer formation using the laying hen model, a biologically relevant animal model of spontaneous ovarian carcinogenesis due to high incidence rates similar to humans.

Methods

In this study, a total of 150 laying hens at age of 102 weeks were randomized into groups of 50: a control group (0 mg of lycopene per kg of diet) and two treatment groups (200 mg or 400 mg of lycopene per kg of diet, or ~26 and 52 mg/d/hen, respectively). At the end of 12 months, blood, ovarian tissues and tumors were collected.

Results

We observed that lycopene supplementation significantly reduced the overall ovarian tumor incidence (P < 0.01) as well as the number and the size of the tumors (P < 0.004 and P < 0.005, respectively). Lycopene also significantly decreased the rate of adenocarcinoma, including serous and mucinous subtypes (P < 0.006). Moreover, we also found that the serum level of oxidative stress marker malondialdehyde was significantly lower in lycopene-fed hens compared to control birds (P < 0.001). Molecular analysis of the ovarian tumors revealed that lycopene reduced the expression of NF-κB while increasing the expression of nuclear factor erythroid 2 and its major target protein, heme oxygenase 1. In addition, lycopene supplementation decreased the expression of STAT3 by inducing the protein inhibitor of activated STAT3 expression in the ovarian tissues.

Conclusions

Taken together, our findings strongly support the potential of lycopene in the chemoprevention of ovarian cancer through antioxidant and anti-inflammatory mechanisms.

Improving cancer detection through combinations of cancer and immune biomarkers: a modelling approach

Background

Early cancer diagnosis is one of the most important challenges of cancer research, since in many cancers it can lead to cure for patients with early stage diseases. For epithelial ovarian cancer (which is the leading cause of death among gynaecologic malignancies) the classical detection approach is based on measurements of CA-125 biomarker. However, the poor sensitivity and specificity of this biomarker impacts the detection of early-stage cancers.

Methods

Here we use a computational approach to investigate the effect of combining multiple biomarkers for ovarian cancer (e.g., CA-125 and IL-7), to improve early cancer detection.

Results

We show that this combined biomarkers approach could lead indeed to earlier cancer detection. However, the immune response (which influences the level of secreted IL-7 biomarker) plays an important role in improving and/or delaying cancer detection. Moreover, the detection level of IL-7 immune biomarker could be in a range that would not allow to distinguish between a healthy state and a cancerous state. In this case, the construction of solution diagrams in the space generated by the IL-7 and CA-125 biomarkers could allow us predict the long-term evolution of cancer biomarkers, thus allowing us to make predictions on cancer detection times.

Conclusions

Combining cancer and immune biomarkers could improve cancer detection times, and any predictions that could be made (at least through the use of CA-125/IL-7 biomarkers) are patient specific.

EphA8 is a prognostic marker for epithelial ovarian cancer

EphA8 is one of the Eph receptors in the Eph/ephrin receptor tyrosine kinase (RTK) subfamily. During tumorigenesis, EphA8 is involved in angiogenesis, cell adhesion and migration. In this study, we determined the mRNA and protein expression levels of EphA8 in cancerous and normal ovarian tissue samples by quantitative reverse transcription PCR (qRT-PCR) (N = 60) and tissue microarray immunohistochemistry analysis (TMA-IHC) (N = 223) respectively. EphA8 protein levels in cancer tissues were correlated with epithelial ovarian cancer (EOC) patients’ clinical characteristics and overall survival. Both EphA8 mRNA and protein levels were significantly higher in EOC tissues than in normal or benign ovarian tissues (all P < 0.05). High EphA8 protein level was associated older age at diagnosis, higher FIGO stage, positive lymph nodes, presence of metastasis, positive ascitic fluid, and higher serum CA-125 level. High EphA8 protein level is an independent prognostic marker in EOC. We conclude that EphA8 acts as an oncogene in EOC development and progression. Detection of EphA8 expression could be a useful prognosis marker and targeting EphA8 represents a novel strategy for EOC treatment.

Constructing an ovarian cancer metastasis index by dissecting medical records

Globally, ovarian cancer (OC) is the leading cause of gynecological cancer-associated deaths. Metastasis, especially multi-organ metastasis, determines the speed of disease progression. A multicenter retrospective study was performed to identify the factors that drive metastasis, from medical records of 534 patients with OC. The average number of target organs per patient was 3.66, indicating multi-organ metastasis. The most common sites of metastasis were large intestine and greater omentum, which were prone to co-metastasis. Results indicated that ascites and laterality, rather than age and menopausal status, were the potential drivers for multi-organ metastasis. Cancer antigen (CA) 125 (CA-125) and nine other blood indicators were found to show a significant, but weak correlation with multi-organ metastasis. A neural network cascade-multiple linear regression hybrid model was built to create an ovarian cancer metastasis index (OCMI) by integration of six multi-organ metastasis drivers including CA-125, blood platelet count, lymphocytes percentage, prealbumin, ascites, and laterality. In an independent set of 267 OC medical records, OCMI showed a moderate correlation with multi-organ metastasis (Spearman ρ = 0.67), the value being 0.72 in premenopausal patients, and good performance in identifying multi-organ metastasis (area under the receiver operating characteristic curve = 0.832), implying a potential prognostic marker for OC.

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.

Combined Application of Ultrasound and CT Increased Diagnostic Value in Female Patients with Pelvic Masses

Purpose. The current study aimed to evaluate whether combined application of ultrasound and CT had increased Diagnostic Value in Female Patients with Pelvic Masses over either method alone. Patients and Methods. 240 female patients with pelvic masses were detected preoperatively with ultrasound and CT prior to surgery. The sensitivity, specificity, and accuracy of ultrasound, CT, and combined ultrasound/CT application were evaluated, respectively. Results. The sensitivity, specificity, and accuracy of ultrasound were 52.8%, 86.7%, and 68.75%, respectively. The sensitivity, specificity, and accuracy of CT were 80.3%, 90.3%, and 85%, respectively. The sensitivity, specificity, and accuracy of combined application of ultrasound and CT were 89%, 94.7%, and 91.7%. The sensitivity, specificity, and accuracy of combined application of ultrasound and CT were higher than those of either ultrasound or CT. Conclusions. The combined application of ultrasound and CT had higher Diagnostic Value in Female Patients with Pelvic Masses than either method alone.

Blood Plasma-Derived Anti-Glycan Antibodies to Sialylated and Sulfated Glycans Identify Ovarian Cancer Patients

Altered levels of naturally occurring anti-glycan antibodies (AGA) circulating in human blood plasma are found in different pathologies including cancer. Here the levels of AGA directed against 22 negatively charged (sialylated and sulfated) glycans were assessed in high-grade serous ovarian cancer (HGSOC, n = 22) patients and benign controls (n = 31) using our previously developed suspension glycan array (SGA). Specifically, the ability of AGA to differentiate between controls and HGSOC, the most common and aggressive type of ovarian cancer with a poor outcome was determined. Results were compared to CA125, the commonly used ovarian cancer biomarker. AGA to seven glycans that significantly (P<0.05) differentiated between HGSOC and control were identified: AGA to top candidates SiaTn and 6-OSulfo-TF (both IgM) differentiated comparably to CA125. The area under the curve (AUC) of a panel of AGA to 5 glycans (SiaTn, 6-OSulfo-TF, 6-OSulfo-LN, SiaLea, and GM2) (0.878) was comparable to CA125 (0.864), but it markedly increased (0.985) when combined with CA125. AGA to SiaTn and 6-OSulfo-TF were also valuable predictors for HGSOC when CA125 values appeared inconclusive, i.e. were below a certain threshold. AGA-glycan binding was in some cases isotype-dependent and sensitive to glycosidic linkage switch (α2-6 vs. α2-3), to sialylation, and to sulfation of the glycans. In conclusion, plasma-derived AGA to sialylated and sulfated glycans including SiaTn and 6-OSulfo-TF detected by SGA present a valuable alternative to CA125 for differentiating controls from HGSOC patients and for predicting the likelihood of HGSOC, and may be potential HGSOC tumor markers.

Lysine-specific demethylase KDM3A regulates ovarian cancer stemness and chemoresistance

Ovarian cancer is the leading cause of death among all gynecological malignancies due to the development of acquired chemoresistance and disease relapse. Although the role of cancer stem cells (CSCs), a subset of tumor cells with the self-renewal and differentiation capabilities, in therapeutic resistance is beginning to be better understood, the significance of epigenetic regulatory mechanisms responsible for integrating the stemness with drug resistance remain poorly understood. Here we identified that lysine demethylase KDM3A as a critical regulator of ovarian cancer stemness and cisplatin resistance by inducing the expressions of pluripotent molecules Sox2 and Nanog and anti-apoptotic B-cell lymphoma 2 (Bcl-2), respectively. In addition, KDM3A induces ovarian cancer growth while antagonizing cellular senescence by repressing the expression of cyclin-dependent kinase inhibitor, p21^Waf1/Cip1. The underlying mechanism of the noted biological processes include KDM3A-mediated stimulation of Sox2 expression, and demethylating p53 protein and consequently, modulating its target genes such as Bcl-2 and p21^Waf1/Cip1 expression. Consistently, KDM3A depletion inhibited the growth of subcutaneously implanted cisplatin-resistant human ovarian cancer cells in athymic nude mice. Moreover, KDM3A is abundantly expressed and positively correlated with Sox2 expression in human ovarian cancer tissues. In brief, our findings reveal a novel mechanism by which KDM3A promotes ovarian CSCs, proliferation and chemoresistance and thus, highlights the significance of KDM3A as a novel therapeutic target for resistant ovarian cancer.

Epigenetic regulation of glycosylation and the impact on chemo-resistance in breast and ovarian cancer

Glycosylation is one of the most fundamental posttranslational modifications in cellular biology and has been shown to be epigenetically regulated. Understanding this process is important as epigenetic therapies such as those using DNA methyltransferase inhibitors are undergoing clinical trials for the treatment of ovarian and breast cancer. Previous work has demonstrated that altered glycosylation patterns are associated with aggressive disease in women presenting with breast and ovarian cancer. Moreover, the tumor microenvironment of hypoxia results in globally altered DNA methylation and is associated with aggressive cancer phenotypes and chemo-resistance, a feature integral to many cancers. There is sparse knowledge on the impact of these therapies on glycosylation. Moreover, little is known about the efficacy of DNA methyltransferase inhibitors in hypoxic tumors. In this review, we interrogate the impact that hypoxia and epigenetic regulation has on cancer cell glycosylation in relation to resultant tumor cell aggressiveness and chemo-resistance.

Comparison of plasma amino acid profile-based index and CA125 in the diagnosis of epithelial ovarian cancers and borderline malignant tumors

BACKGROUND

We previously developed a new plasma amino acid profile-based index (API) to detect ovarian, cervical, and endometrial cancers. Here, we compared API to serum cancer antigen 125 (CA125) for distinguishing epithelial ovarian malignant tumors from benign growths.

METHODS

API and CA125 were measured preoperatively in patients with ovarian tumors, which were later classified into 59 epithelial ovarian cancers, 21 epithelial borderline malignant tumors, and 97 benign tumors including 40 endometriotic cysts. The diagnostic accuracy and cutoff points of API were evaluated using receiver operating characteristic (ROC) curves.

RESULTS

The area under the ROC curves showed the equivalent performance of API and CA125 to discriminate between malignant/borderline malignant and benign tumors (both 0.77), and API was superior to CA125 for discrimination between malignant/borderline malignant lesions and endometriotic cysts (API, 0.75 vs. CA125, 0.59; p < 0.05). At the API cutoff level of 6.0, API and CA125 had equal positive rates of detecting cancers and borderline malignancies (API, 0.71 vs. CA125, 0.74; p = 0.84) or cancers alone (API, 0.73 vs. CA125, 0.85; p = 0.12). However, API had a significantly lower detection rate of benign endometriotic cysts (0.35; 95 % CI, 0.21-0.52) compared with that of CA125 (0.65; 95 % CI, 0.48-0.79) (p < 0.05).

CONCLUSIONS

API is an effective new tumor marker to detect ovarian cancers and borderline malignancies with a low false-positive rate for endometriosis. A large-scale prospective clinical study using the cutoff value of API determined in this study is warranted to validate API for practical clinical use.

Level of HE4 is Correlated with Diagnosis of Struma Ovarii: A Case Report

BACKGROUND Struma ovarii is a rare ovarian teratoma with non-specific clinical presentation that can mimic malignancy, especially when combined with the presence of ascites. Since the surgical procedures performed for benign and malignant tumors are quite different, pre-operative differential diagnosis is key. In this case report we compare the levels of biomarkers CA 125 and HE4 in the differential diagnosis of a suspicious ovarian tumor. CASE REPORT A 75-year-old woman with a palpable mass at the left adnexa, ascites, and high levels of CA 125, underwent a subtotal abdominal hysterectomy and bilateral salpingo-oophorectomy. Histology reported benign struma ovarii. CONCLUSIONS Even though transvaginal ultrasound and CA 125 levels suggested malignancy, HE4 measurements correctly diagnosed benignity.

Upregulation of miR-572 transcriptionally suppresses SOCS1 and p21 and contributes to human ovarian cancer progression

Ovarian cancer is a gynecological malignancy with high mortality rates worldwide and novel diagnostic and prognostic markers and therapeutic targets are urgently required. The suppressor of cytokine signaling 1 (SOCS1) and cyclin-dependent kinase inhibitor 1A (p21^KIP) are known to regulate tumor cell proliferation. However, the mechanisms that regulate these genes have not yet been completely elucidated. In the present study, analysis of a published microarray-based high-throughput assessment (NCBI/E-MTAB-1067) and real-time PCR demonstrated that miR-572 was upregulated in human ovarian cancer tissues and cell lines. Kaplan-Meir analysis indicated that high level expression of miR-572 was associated with poorer overall survival. Ectopic miR-572 promoted ovarian cancer cell proliferation and cell cycle progression in vitro and tumorigenicity in vivo. SOCS1 and p21 were identified as direct targets of miR-572 and suppression of SOCS1 or p21 reversed the inhibiting-function of miR-572-silenced cell on proliferation and tumorigenicity in ovarian cancer cells. Additionally, the expression of miR-572 correlated inversely with the protein expression levels of SOCS1, p21 and positively with Cyclin D1 in ovarian carcinoma specimens. This study demonstrates that miR-572 post-transcriptionally regulates SOCS1 and p21 and may play an important role in ovarian cancer progression; miR-572 may represent a potential therapeutic target for ovarian cancer therapy.

Elevated growth differentiation factor 15 expression predicts poor prognosis in epithelial ovarian cancer patients

The purpose of this study was to determine the expression of growth differentiation factor 15 (GDF15) and explore its clinical significance in epithelial ovarian cancer (EOC) patients. The expression of GDF15 in EOC tissues and serum samples was evaluated using immunohistochemistry and enzyme-linked immunosorbent assay (ELISA), respectively. The association of GDF15 expression with clinicopathologic parameters was analyzed. Survival time was assessed using the Kaplan-Meier technique and Cox regression model. Both in EOC tissues and serum, high GDF15 levels were obviously related with advanced International Federation of Gynecology and Obstetrics (FIGO) stage, lymph node metastasis, ascites, and chemoresistance. Kaplan-Meier analysis indicated that EOC patients with high GDF15 expression showed poorer progression-free survival (PFS) and overall survival (OS). Multivariate analysis demonstrated that GDF15 expression was an independent predictor of PFS in EOC patients. Our study shows that elevated GDF15 expression was associated with poor prognosis in EOC patients. We suggest that GDF15 is a novel biomarker for the early detection of EOC, prediction of the response to chemotherapy, and screening for recurrence in EOC patients.

Proteomics of ovarian cancer: functional insights and clinical applications

In the past decade, there has been an increasing interest in applying proteomics to assist in understanding the pathogenesis of ovarian cancer, elucidating the mechanism of drug resistance, and in the development of biomarkers for early detection of ovarian cancer. Although ovarian cancer is a spectrum of different diseases, the strategies for diagnosis and treatment with surgery and adjuvant therapy are similar across ovarian cancer types, increasing the general applicability of discoveries made through proteomics research. While proteomic experiments face many difficulties which slow the pace of clinical applications, recent advances in proteomic technology contribute significantly to the identification of aberrant proteins and networks which can serve as targets for biomarker development and individualized therapies. This review provides a summary of the literature on proteomics' contributions to ovarian cancer research and highlights the current issues, future directions, and challenges. We propose that protein-level characterization of primary lesion in ovarian cancer can decipher the mystery of this disease, improve diagnostic tools, and lead to more effective screening programs.

Current state of biomarkers in ovarian cancer prognosis

High-grade serous ovarian cancer remains one of the most lethal malignancies in women. Despite recent advances in surgical and pharmaceutical therapies, survival rates remain poor. A major impediment in management of this disease, that continues to contribute to poor overall survival rates, is resistance to standard carboplatin-paclitaxel combination chemotherapies. In addition to tumor cell intrinsic mechanisms leading to drug resistance, there is increasing awareness of the crucial role of the tumor microenvironment in mediating natural immune defense mechanisms and selective pressures that appear to facilitate chemotherapy sensitivity. We provide an overview of some of the promising new genetic and immunological biomarkers in ovarian cancer and discuss their biology and their likely clinical utility in future ovarian cancer management.

Overexpression of centromere protein K (CENPK) in ovarian cancer is correlated with poor patient survival and associated with predictive and prognostic relevance

Ovarian cancer has a poor prognosis. Most patients are diagnosed with ovarian cancer when the disease has reached an advanced stage and cure rates are generally under 30%. Hence, early diagnosis of ovarian cancer is the best means to control the disease in the long term and abate mortality. So far, cancer antigen 125 (CA125) and human epididymis protein 4 (HE4) are the gold-standard tumor markers for ovarian cancer; however, these two markers can be elevated in a number of conditions unrelated to ovarian cancer, resulting in decreased specifically and positive predictive value. Therefore, it is urgent to identify novel biomarkers with high reliability and sensitivity for ovarian cancer. In this study for the first time, we identified a member of the centromere protein (CENP) family, CENPK, which was specifically upregulated in ovarian cancer tissues and cell lines and the overexpression of which was associated with poor prognoses in patients with ovarian cancer. In addition, the presence of CENPK significantly improved the sensitivity of CA125 or HE4 for predicting clinical outcomes of ovarian cancer patients. In conclusion, we identified that CENPK was specifically upregulated in ovarian cancer cells and can be used as a novel tumor marker of ovarian cancer.

In vitro selection of RNA aptamers against CA125 tumor marker in ovarian cancer and its study by optical biosensing

Early identification of neoplastic diseases is essential to achieve timely therapeutic interventions and significantly reduce the mortality of patients. A well-known biomarker is the Cancer Antigen 125 (CA125) or 16 mucin (MUC 16), a glycoprotein of the human family of mucins, already used for the diagnostic and prognostic evaluation of ovarian cancer. Therefore, the detection of CA125 to now remains a promising tool in the early diagnosis of this tumor. In this paper, we describe the development of RNA aptamers that bind with high affinity the tumor antigen CA125. We performed eight cycles of selection against CA125 purified protein. The selected aptamers were cloned and sequenced and the binding properties of the most promising sequences were studied by Real Time PCR and Surface Plasmon Resonance (SPR) to evaluate their ability in targeting CA125 protein with perspective applications in aptamer-based bioassays.

Gallic acid, a phenolic compound, exerts anti-angiogenic effects via the PTEN/AKT/HIF-1α/VEGF signaling pathway in ovarian cancer cells

Gallic acid (GA), a polyphenol, is widely found in numerous fruits and vegetables, particularly in hickory nuts. In the present study, we found that gallic acid, a natural phenolic compound isolated from fruits and vegetables, had a more potent growth inhibitory effect on two ovarian cancer cell lines, OVCAR-3 and A2780/CP70, than the effect on a normal ovarian cell line, IOSE-364. These results demonstrated that GA selectively inhibits the growth of cancer cells. Gene expression was examined by ELISA and western blot analysis, and gene pathways were examined by luciferase assay. It was found that GA inhibited VEGF secretion and suppressed in vitro angiogenesis in a concentration-dependent manner. GA downregulated AKT phosphorylation as well as HIF-1α expression but promoted PTEN expression. The luciferase assay results suggest that the PTEN/AKT/HIF-1α pathway accounts for the inhibitory effect of GA on VEGF expression and in vitro angiogenesis. These findings provide strong support for the high potential of GA in the prevention and therapy of ovarian cancer.

Correlation analysis of urine metabolites and clinical staging in patients with ovarian cancer

This study is to investigate the correlation between urine metabolites and clinical staging in patients with ovarian cancer. The urina sanguinis from 56 cases of primary epithelial ovarian cancer patients and 15 healthy volunteers was collected and the urine metabolites were extracted. Ultra high performance liquid chromatography/time-of-flight mass spectrometry (UPLC-Q-TOF-MS) analysis was performed. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to analyze the mass spectrometry data. Database retrieval and comparison of the screened metabolites were performed and one-way ANOVA and least significant difference (LSD) t test were carried out. PCA analysis of UPLC-Q-TOF-MS results showed that the score plots of samples from healthy people and patients with ovarian cancer at different clinical stages were separated. Further PLS-DA analysis significantly improved the classification results. The R(2)X was 0.757, the R(2)Y was 0.977 and the Q(2)Y was 0.87, indicating that the model stability and predictability were good. Eight metabolites, including N-acetylneuraminic acid-9-phosphate, 5'-methioadenosine, uric acid-3-nucleoside, pseudouridine, L-valine, succinic acid, L-proline and β-nicotinamide mononucleotide were identified. The contents of these metabolites increased with the development of the disease. There was correlation between urine metabolites and clinical staging in patients with ovarian cancer.

Urinary microRNA-30a-5p is a potential biomarker for ovarian serous adenocarcinoma

MicroRNAs (miRNAs) can serve as biomarkers in human cancer. To determine the clinical value of urinary miRNAs for ovarian serous adenocarcinoma, we collected urine samples from 39 ovarian serous adenocarcinoma patients, 26 patients with benign gynecological disease and 30 healthy controls. The miRNA microarray data showed that only miR-30a-5p was upregulated and 37 miRNAs were downregulated in the urine samples of ovarian serous adenocarcinoma patients, when compared to healthy controls, which was confirmed after conducting quantitative PCR. The upregulation of urinary miR-30a-5p was closely associated with early stage of ovarian serous adenocarcinoma as well as lymphatic metastasis. Receiver operator characteristic (ROC) analysis demonstrated the potential use of urinary miR-30a-5p as a diagnostic marker for ovarian serous adenocarcinoma. Furthermore, a lower urine level of miR-30a-5p was found in 20 gastric cancer and 20 colon carcinoma patients when compared to ovarian serous adenocarcinoma, suggesting that the upregulation of urinary miR-30a-5p may be specific for ovarian serous adenocarcinoma. miR-30a-5p was also upregulated in ovarian serous adenocarcinoma tissues and cell lines, while urinary miR-30a-5p from ovarian cancer patients was notably reduced following the surgical removal of ovarian serous adenocarcinoma, suggesting that urinary miR-30a-5p was derived from the ovarian serous adenocarcinoma tissue. Notably, miR-30a-5p was concentrated with exosomes from the ovarian cancer cell supernatant or urine from ovarian serous adenocarcinoma patients, supporting a pathway for excretion into the urine. The results also showed that the knockdown of miR-30a-5p significantly inhibited the proliferation and migration of ovarian cancer cells. In summary, to the best of our knowledge, the present study provided the first evidence of increased miR-30a-5p in the urine of ovarian serous adeno-carcinoma patients, while the inhibition of miR-30a-5p suppressed the malignant phenotypes of ovarian cancer in vitro. Therefore, miR-30a-5p serves as a promising diagnostic and therapeutic target for ovarian serous adenocarcinoma.

Identification of epithelial ovarian tumor-specific aptamers

Ovarian cancer is often diagnosed in late stages with few treatment options and poor long-term prognosis. New clinical tools for early detection of ovarian malignancies will significantly help reduce mortality and improve current long-term survival rates. The objective of this work was to identify ovarian tumor-specific single-stranded DNA aptamers that bind to malignant ovarian tumor cells and internalize with high affinity and specificity. Aptamers can identify unique tumor biomarkers, can aid in early detection and diagnosis of neoplastic disorders, and can be functionalized by conjugation to small molecules. To identify aptamers from random single-stranded DNA pools (60 bases long), we used whole Cell-SELEX (systematic evolution of ligands by exponential enrichment) to enrich and isolate tumor-specific aptamers that bind to tumor-specific receptors in their native state on the cell surface. Next-Generation sequencing identified seven novel aptamers and detailed analyses of three are described. Aptamers bound to, and were internalized by, target Caov-3 cell populations, but not nontarget nonmalignant ovarian epithelial HOSE 6-3 cells or multiple other epithelial tumor cell lines. Furthermore, aptamers showed unique binding affinities with apparent dissociation constants (Kd) measuring in the submicromolar range supporting their physiological relevance and potential use in clinical applications.

Diagnostic performance of contrast-enhanced ultrasound for ovarian cancer: a meta-analysis

This meta-analysis is the first study aimed at assessing the overall diagnostic performance of contrast-enhanced ultrasound for ovarian cancer. PubMed, Embase and Medline databases were systematically searched for relevant articles published up to June 2014. Data were pooled to yield summary sensitivity, specificity, diagnostic odds ratio and receiver operating characteristic curves using Meta-Disc Version 1.4 software. Ten independent studies with 579 ovarian tumors were enrolled in this meta-analysis. The pooled sensitivity, specificity and diagnostic odds ratio statistics were 0.89 (0.83-0.94), 0.91 (0.88-0.93) and 91.70 (41.41-203.05), respectively, and the area under the summary receiver operating characteristic curve was 0.9619 (standard error: 0.0125), all indicating that contrast-enhanced ultrasound has high diagnostic accuracy in differentiation of malignant from benign ovarian tumors.

Highly effective antiangiogenesis via magnetic mesoporous silica-based siRNA vehicle targeting the VEGF gene for orthotopic ovarian cancer therapy

Therapeutic antiangiogenesis strategies have demonstrated significant antitumor efficacy in ovarian cancer. Recently, RNA interference (RNAi) has come to be regarded as a promising technology for treatment of disease, especially cancer. In this study, vascular endothelial growth factor (VEGF)-small interfering RNA (siRNA) was encapsulated into a magnetic mesoporous silica nanoparticle (M-MSN)-based, polyethylenimine (PEI)-capped, polyethylene glycol (PEG)-grafted, fusogenic peptide (KALA)-functionalized siRNA delivery system, termed M-MSN_VEGF siRNA@PEI-PEG-KALA, which showed significant effectiveness with regard to VEGF gene silencing in vitro and in vivo. The prepared siRNA delivery system readily exhibited cellular internalization and ease of endosomal escape, resulting in excellent RNAi efficacy without associated cytotoxicity in SKOV3 cells. In in vivo experiments, notable retardation of tumor growth was observed in orthotopic ovarian tumor-bearing mice, which was attributed to significant inhibition of angiogenesis by systemic administration of this nanocarrier. No obvious toxic drug responses were detected in major organs. Further, the magnetic core of M-MSN_VEGF siRNA@PEI-PEG-KALA proved capable of probing the site and size of the ovarian cancer in mice on magnetic resonance imaging. Collectively, the results demonstrate that an M-MSN-based delivery system has potential to serve as a carrier of siRNA therapeutics in ovarian cancer.

Inhibition of IL-6/STAT3 axis and targeting Axl and Tyro3 receptor tyrosine kinases by apigenin circumvent taxol resistance in ovarian cancer cells

Ovarian cancer is the number one cause of death from gynaecological malignancy. Platinum-based and taxol-based chemotherapy has been used as a standard therapy, but intrinsic and acquired resistance to chemotherapy is a major obstacle to treat the disease. In the present study, we found that in the chemoresistant ovarian cancer SKOV3/TR cells, interleukin-6 (IL-6), IL-6 receptor and signal transducers and activators of transcription 3 (STAT3) expression as well as STAT3 phosphorylation were upregulated compared to those in parental cells. Silencing of IL-6 using IL-6 siRNA was found to suppress IL-6 production, STAT3 and phosphoSTAT3 levels, which eventually reduced proliferation and clonogenicity of taxol-resistant SKOV3/TR cells. In addition, stattic, a STAT3 inhibitor, was found to result in decrease of cell viability and clonogenicity of these cells, indicating that the elevated IL-6 and STAT3, phosphoSTAT3 levels are associated with the development of taxol resistance. Next, we found anti-proliferative effect of apigenin on both SKOV3 and SKOV3/TR cells. RT-PCR and western blot results showed that apigenin significantly reduced the expression of Axl and Tyro3 receptor tyrosine kinases (RTKs) at mRNA and protein level, which account for its cytotoxic activity. We further found that apigenin decreased Akt phosphorylation and the level of B-cell lymphoma-extra large (Bcl-xl or BCL2-like 1 isoform 1), an inhibitor of apoptosis. On the contrary to these results, apigenin had no effect on IL-6 production, STAT3 and phosphoSTAT3 protein levels, suggesting that apigenin exerts its anti-proliferative activity via downregulation of Axl and Tyro3 expression, Akt phosphorylation and Bcl-xl expression, but not modulation of IL-6/STAT3 axis. Taken together, our data suggest that inhibition of IL-6/STAT3 signaling pathway and downregulation of Axl and Tyro3 RTKs expression might be a therapeutic strategy to overcome taxol resistance in ovarian cancer cells.