Diagnosis and management of epithelial ovarian cancer

Do PET-positive supradiaphragmatic lymph nodes predict overall survival or the success of primary surgery in patients with advanced ovarian cancer?

OBJECTIVES

Compared to conventional computed tomography (CT), fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) detects higher rates of lymph node and distant metastases in patients with ovarian cancer. However, FDG-PET/CT is not routinely performed during preoperative work-up. Therefore, we investigated the prognostic value of preoperative FDG-PET/CT in advanced epithelial ovarian cancer (EOC) and its predictive value for surgical resection in patients with no residual disease. The potential significance of PET-positive supradiaphragmatic lymph nodes (SDLNs) for these parameters was evaluated.

METHODS

All patients with FIGO IIA-IVB EOC diagnosed between March 2014 and January 2021 at our certified gynaecological cancer centre, who underwent FDG PET/CT before primary surgery were retrospectively included.

RESULTS

Fifty-three consecutive patients were included in the study. Eighteen (34 %) patients had PET-positive SDLNs. We could not demonstrate a significant correlation between PET-positive SDLNs and median overall survival (OS; SDLN-positive: 58.76 months, SDLN-negative: 60.76 months; p = 0.137) or intra- or perioperative outcomes.

CONCLUSIONS

FDG PET/CT has a higher detection rate for SDLNs in patients with ovarian cancer than CT has, as described in the literature. Moreover, PET-positive SDLNs failed to predict intraoperative outcomes or overall survival.

BRCA mutation carriers suffering from ovarian cancer as a model for treatment decision in higher lines - Place for platinum reinduction

Context

Ovarian carcinoma is a malignancy with the highest mortality among gynecological cancers. Mutations in BRCA1/2 genes are believed to be a favorable prognostic factor and that, in general, the biological behavior of ovarian cancer in BRCA-positive individuals differs from others. However, some clinically relevant issues (i.e., prediction of response to chemotherapy and treatment of platinum-resistant BRCA-positive patients) remain unclear.

Aims

(1) The aim of this study was to examine the prevalence of germline BRCA mutations in unselected recurrent ovarian cancer patient population, (2) analyze whether biological behavior of BRCA-positive tumors differs from others, and (3) analyze the effect of platinum reinduction in platinum-resistant BRCA-positive patients.

Settings and Design

This was a single-institution retrospective analysis.

Subjects and Methods

Consecutive recurrent ovarian cancer patients from years 2012 to 2020 were included; their BRCA1/2 mutational status was analyzed and correlated with progression-free survival (PFS), type of treatment, and response to treatment.

Statistical Analysis Used

Statistical significance of differences between and among patients was tested for continuous variables by the Mann-Whitney U-test or the Kruskal-Wallis test; a maximum likelihood Chi-square test was used for categorical variables.

Results

Two hundred and forty-three recurrent ovarian cancer patients were included. The median follow-up was 37 months. Pathogenic mutation in BRCA1 or BRCA2 gene was found in 18.1% of patients. There was no difference in PFS comparing BRCA-positive to BRCA-negative patients (median PFS: 10.2 vs. 10.1 months, P = 0.874); there was a difference in PFS comparing BRCA-negative versus BRCA-positive platinum-sensitive patients (9.4 vs. 14.3 months, P = 0.002). BRCA-positive platinum-resistant patients reinduced with platinum achieved a median PFS of 8 months (compared to those receiving nonplatinum treatment, median PFS: 4 months, P = 0.062).

Conclusions

Germline BRCA mutations are not exclusive to platinum-sensitive ovarian cancer patients; even in platinum-resistant patients, mutation can be detected. We found no difference in PFS for platinum-sensitive BRCA-positive and BRCA-negative patients. Platinum reinduction may be considered for BRCA-positive platinum-resistant ovarian cancer patients to prolong PFS. Even these data describe only a small population, it supports the clinical practice of platinum-based chemotherapy use in platinum-resistant BRCA-positive patients.

A phase II evaluation of temsirolimus with carboplatin and paclitaxel followed by temsirolimus consolidation in clear cell ovarian cancer: An NRG oncology trial

OBJECTIVE

The primary objective of the study was to estimate the 12-month progression-free survival (PFS) for carboplatin/paclitaxel + temsirolimus in women with newly diagnosed clear cell ovarian cancer (CCOC), compared to historical controls in this patient population.

METHODS

Patients with Stage III or IV CCOC were treated with Paclitaxel 175 mg/m2 on Day 1, Carboplatin AUC 6 Day 1, and temsirolimus (CCI-779) 25 mg IV Days 1 and 8 every 3 weeks for Cycles 1-6 or disease progression, followed by consolidation therapy with temsirolimus 25 mg Days 1, 8, and 15 every 3 weeks cycles 7-17 or until disease progression.

RESULTS

Ninety patients were accrued to the study: 45 in the US and Korea (US/Korea) and 45 in Japan. Twenty-two percent received ≤6 cycles of therapy while 28% completed all 17 cycles of chemotherapy. Median PFS (OS) was 11 (23) months for US/Korea and 12 (26) months for Japan. In the US, none of suboptimally debulked patients had PFS >12 months, and 49% of optimal patients did, compared to 25% and 59% in Japan. Most common grade 3-4 adverse events were neutropenia, leukopenia, anemia, thrombocytopenia, hypertension, hypertriglyceridemia, and oral mucositis.

CONCLUSION

The carboplatin/paclitaxel + temsirolimus regimen was well tolerated. In optimally debulked patients, 54% had a PFS >12 months. This regimen did not statistically significantly increase PFS at 12 months compared to historical controls. No statistically significant differences in PFS or OS were observed between US/Korea vs Japan, or Asians vs non-Asians.

Polymeric nanoparticles-siRNA as an emerging nano-polyplexes against ovarian cancer

Ovarian cancer (OC) is considered fifth-deadliest cancer globally responsible for high mortality in women. As the conventional therapeutic and diagnostic approaches are ineffective in increasing the survival rates of advanced staged patients by more than 5 years, OC has resulted in high morbidity and mortality rates over the last two decades. As a result, there is a dire need for innovative treatment approaches to address the issues. RNAi and nanotechnology can be considered the most appropriate strategies that can be used to improve OC therapy and help circumvent the chemo-resistance. siRNA is considered highly successful in facilitating the knockdown of specific genes on entering the cytosol when administered in-vivo via inhibiting the mRNA expression responsible for translation of those specific genes through the mechanism called RNA interference (RNAi). However, the primary barrier of utmost importance in the clinical efficacy of employed siRNA for the treatment of OC is the systemic distribution to the targeted site from the administration site. As a result, nanoparticles are constructed to carry the siRNA molecules inside them to the targeted site by preventing serum degradation and enhancing the serum stability of administered siRNA. The present review assesses the developments made in the polymeric-based nanoparticle siRNA delivery for targeting particular genes involved in the prognosis of ovarian cancers and surpassing the chemo-resistance and thus improving the therapeutic potentials of administered agents.

Regulatory Role of the Adipose Microenvironment on Ovarian Cancer Progression

Simple Summary

Adipocytes or fat cells are integral part of the ovarian tumor microenvironment. Secreted factors from adipocytes, as well as direct cell-to-cell interaction with ovarian cancer cells have been shown to directly support ovarian tumor progression. Elucidating the molecular pathways involved is crucial in the identification of relevant targets.

Abstract

The tumor microenvironment of ovarian cancer is the peritoneal cavity wherein adipose tissue is a major component. The role of the adipose tissue in support of ovarian cancer progression has been elucidated in several studies from the past decades. The adipocytes, in particular, are a major source of factors, which regulate all facets of ovarian cancer progression such as acquisition of chemoresistance, enhanced metastatic potential, and metabolic reprogramming. In this review, we summarize the relevant studies, which highlight the role of adipocytes in ovarian cancer progression and offer insights into unanswered questions and possible future directions of research.

Ovarian cancer and KiSS-1 gene expression: A consideration of the use of Kisspeptin plus Kisspeptin aptamers in diagnostics and therapy

Gynaecological cancers continue to present a significant health burden upon the health of the global female population. This deficit is most prominent with ovarian cancer which possesses the lowest survival rate compared to all other cancers occurring within this anatomical region, with an annual UK-mortality of 7,300. The poor tolerability and selectively of the treatment options that are currently available is likely to have contributed to this high mortality rate thus, demonstrating the need for the development of enhanced therapeutic approaches. Aptamer technology would involve the engineering of specifically sequenced oligonucleotide chains, which bind to macromolecular targets with a high degree of affinity and selectively. Recent in-vitro studies conducted upon the clinical utility of this technique have supported its superiority in targeting individual therapeutic drug targets compared to various other targeting moieties currently within therapeutic use such as, monoclonal antibodies. For this reason, the employment of this technique is likely to be favourable in reducing the incidence of non-specific, chemotherapy-associated adverse effects. Kisspeptin is a naturally expressed polypeptide with an established role in the development of the reproductive system and other proposed roles in influencing the ability of ovarian cancer growths to exhibit the metastasis hallmark. This distinctive feature would indicate the potential for the manipulation of this pathway through the application of aptamer structures in developing a novel prophylactic strategy and improve the long-term outcome for ovarian cancer patients.

Androgen/Androgen Receptor Signaling in Ovarian Cancer: Molecular Regulation and Therapeutic Potentials

Ovarian cancer (OVCA) arises from three cellular origins, namely surface epithelial cells, germ cells, and stromal cells. More than 85% of OVCAs are EOCs (epithelial ovarian carcinomas), which are the most lethal gynecological malignancies. Cancer stem/progenitor cells (CSPCs) are considered to be cancer promoters due to their capacity for unlimited self-renewal and drug resistance. Androgen receptor (AR) belongs to the nuclear receptor superfamily and can be activated through binding to its ligand androgens. Studies have reported an association between AR expression and EOC carcinogenesis, and AR is suggested to be involved in proliferation, migration/invasion, and stemness. In addition, alternative AR activating signals, including both ligand-dependent and ligand-independent, are involved in OVCA progression. Although some clinical trials have previously been conducted to evaluate the effects of anti-androgens in EOC, no significant results have been reported. In contrast, experimental studies evaluating the effects of anti-androgen or anti-AR reagents in AR-expressing EOC models have demonstrated positive results for suppressing disease progression. Since AR is involved in complex signaling pathways and may be expressed at various levels in OVCA, the aim of this article was to provide an overview of current studies and perspectives regarding the relevance of androgen/AR roles in OVCA.

The involvement of small heat shock protein in chemoresistance in ovarian cancer - in vitro study

Ovarian cancer is the most deadly gynecologic malignancy worldwide. Although the primary response to chemotherapy is high, the majority of patients will develop resistance against applied treatment. In this study, we focused on resistance to cisplatin, a first-line drug used for the treatment of ovarian cancer. The mechanism of the resistance development process is widely described, but there is a lack of information about the involvement of members of small heat shock proteins (HSPs) and their transport via exosomes. In this study, we used two cell lines: A2780 and SKOV3, and their cisplatin-resistance variants: A2780 CDDP and SKOV3 CDDP. We have shown that the expression of three small HSPs (HSPB5, HSPB6, and HSPB8) in cisplatin-resistant cell lines differs from their sensitive counterparts. Further, we isolated exosomes and determined the small HSPs in their cargo. In A2780 WT we observed a low amount of HSPB5 and HSPB6. We did not observe the expression of small HSPs in the SKOV3 cell line in both sensitive and resistant variants. Our data suggest the involvement of small HSPs in drug resistance of ovarian cancer and their presence is not related to exosomal transport. Analysis of the biological consequences of the imbalance of small HSPs expression in cisplatin resistance needs further investigation.

Effect of shikonin on the proliferation and apoptosis of human ovarian cancer cell SKOV3: A protocol of systematic review and meta-analysis

BACKGROUND

This study will investigate the effect of shikonin on the proliferation and apoptosis of human ovarian cancer cell SKOV3 (HOCC-SKOV3).

METHODS

We will retrieve potential studies from inception to the March 1, 2020 in Cochrane Library, MEDLINE, EMBASE, Scopus, Cumulative Index to Nursing and Allied Health Literature, WANGFANG, and China National Knowledge In-frastructure. There are not restrictions related to the language and publication status. This study will include case-controlled studies (CCSs) or randomized controlled studies (RCSs) that examine the effect of shikonin on the proliferation and apoptosis of HOCC-SKOV3. Two researchers will independently identify literatures, extract data, and appraise study quality. Any disagreements will be resolved by discussion with another researcher. RevMan 5.3 software will be placed to perform statistical analysis.

RESULTS

This study will summarize the present evidence to test the effect of shikonin on the proliferation and apoptosis of HOCC-SKOV3.

CONCLUSION

It will provide evidence to investigate the effect of shikonin on the proliferation and apoptosis of HOCC-SKOV3, and will supply reference for further study.Systematic review registration: INPLASY202040146.

Stereotactic body radiation therapy in the treatment of ovarian cancer

BACKGROUND

This study evaluates the outcomes and toxicity of stereotactic body radiation therapy (SBRT) in ovarian cancer.

METHODS

This retrospective analysis considered all patients treated with SBRT from 2009 to 2018 with a primary ovarian tumor. Follow-up included PET-CT and CT scans at 2-3 month intervals. Statistical analysis primarily consisted of univariate analysis, Cox proportional hazards analysis, and the Kaplan-Meier method.

RESULTS

The study included 35 patients with 98 treatments for lymph nodes (51), local recurrence (21), and de novo solid metastases (26). Median biologically effective dose (BED), gross tumor volume, and planning target volume were 38.40 Gy, 10.41 cc, and 25.21 cc, respectively. 52 lesions showed complete radiographic response, and two-year local control was 80%. Median overall survival (OS) was 35.2 months, and two-year progression-free survival (PFS) was 12%. On univariate analysis, Eastern Cooperative Oncology Group performance status > 0 was predictive of decreased OS (p = 0.0024) and PFS (p = 0.044). Factors predictive of local failure included lower BED (p = 0.016), treatment for recurrence (p = 0.029), and higher pre-treatment SUV (p = 0.026). Kaplan-Meier analysis showed BED ≤35 Gy (p < 0.005) and treatment for recurrence (p = 0.01) to be predictive of local failure. On Cox proportional hazards analysis, treatment of lymph nodes was predictive of complete radiographic response (hazard ratio (HR) = 4.95), as was higher BED (HR = 1.03). Toxicity included 27 cases of grade < 3 toxicity, and one grade 5 late toxicity of GI bleed from a radiation therapy-induced duodenal ulcer.

CONCLUSIONS

SBRT provides durable local control with minimal toxicity in ovarian cancer, especially with BED > 35 Gy and treatment for lymph nodes.

Long non-coding RNA LINC00504 regulates the Warburg effect in ovarian cancer through inhibition of miR-1244

Ovarian cancer (OC) is the most lethal gynecologic malignancy and long non-coding RNAs (lncRNAs) have been acknowledged as important regulators in human OC. This study aimed to investigate the function and underlying mechanisms of LINC00504 in OC. The expression levels of LINC00504 in human OC tissues and cell lines were investigated by qRT-PCR analysis. The OC cell proliferation, and apoptosis were evaluated by MTT assay, colony-formation assay, Caspase-3 activity assay, and nucleosome ELISA assay, respectively. The metabolic shift in OC cells was examined by aerobic glycolysis analysis. Dual-luciferase activity reporter assay and mRNA-miRNA pull-down assay were conducted to validate the interaction between LINC00504 and miR-1244. LINC00504 was upregulated in OC cell lines and specimens. Knockdown of LINC00504 inhibited cell proliferation, enhanced apoptosis, decreased glycolysis-related gene (PKM2, HK2, and PDK1) expression, and altered aerobic glycolysis in OC cells and vice versa. LINC00504 downregulated miR-1244 expression levels by acting as an endogenous sponge of miR-1244. Inhibition of miR-1244 diminished the effects of LINC00504 on OC cells. Our study shows that LINC00504 promotes OC cell progression and stimulates aerobic glycolysis by interacting with miR-1244, which indicates that LINC00504 might act as a promising therapeutic target for OC treatment.

Diagnostic performance of HE4 and ROMA among Chinese women

OBJECTIVE

Human epididymis protein 4 (HE4) has been suggested as a new biomarker for the detection of ovarian cancer. Because there are few reports on HE4 in terms of ovarian cancer diagnosis in the Chinese population, we evaluated the diagnostic performances of HE4 and the ROMA in Chinese women with pelvic masses.

METHODS

The serum concentrations of CA 125 and HE4 in 318 Chinese women with pelvic masses (39 of which were ovarian cancers) were determined.

RESULTS

For the discrimination of benign gynecological diseases from ovarian cancer, the sensitivity and specificity values were 87.2% and 75.8% for the ROMA and 51.3% and 97.3% for HE4. The ROMA also showed higher sensitivity than HE4 in both the early and advanced stages. In the ROC curve analysis, the AUC values for ROMA, HE4 and CA 125 were 0.927, 0.907 and 0.785, respectively.

CONCLUSIONS

As a new tumor marker, HE4 shows high specificity and efficacy in the Chinese population, while the ROMA that combines HE4 and CA 125 shows high sensitivity and a high Youden's index. These markers should be extended to China since they have good diagnostic performances.

The apoptotic effect of resveratrol in ovarian cancer cells is associated with downregulation of galectin-3 and stimulating miR-424-3p transcription

This study investigated if the well-reported anti-tumor effects of resveratrol (RES) is mediated by modulation levels of galectin-3 (GAL-3), an anti-apoptotic lectin that is highly overexpressed in ovarian cancer cells. SKOV3 and OVCAR-3 OC cells were untreated or incubated with DMOS or increasing concentrations of RES (25, 50, 100 μM) for 72 hr. RES, in a dose-dependent manner and in both cell lines, induced cell death and inhibited cell migration and invasion It also downregulated Bcl-2 levels, increased cleaved caspase-3, and GAL-3 protein (but not mRNA) levels, suggesting increased breakdown. These effects were associated with reduced levels of p-NF-κB P65, p-IKKα/β, and p-Akt, major targets of Gal-3. Further investigation showed that RES enhanced levels of miR-424-3p which is able to degrade GAL-3. Conclusion: Findings of this study suggest that RES induced apoptosis in cancerous cells is associated with increased levels of miR-424-3p and reduced levels of GAL-3. PRACTICAL APPLICATIONS: This study highlights a possible mechanism by which RES could enhance cell death in OC cells and enhances their sensitivity to cisplatin. RES apoptotic effect and enhancement of OC cells to chemotherapy were associated with decreased abundance of GAL-3, a common cell survival molecule that promotes tumorigenesis and increased transcription of miR-424-3p that has the ability to degrade cellular GAL-3. These findings add a possible new mechanism by which RES acts and opens a window for further research to understand its mechanism of action.

Role of Jagged1/STAT3 signalling in platinum-resistant ovarian cancer

Jagged1, the essential ligand of the Notch signalling pathway, is highly expressed in metastatic prostate cancer, and its high expression in breast cancer is linked to poor survival rates. However, the mechanism of Jagged1′s involvement in platinum‐resistant ovarian cancer has not been thoroughly elucidated to date. The purpose of the present study was to investigate the roles of Jagged1 in the platinum resistance of ovarian cancer and its possible mechanisms. Compared with a platinum responsive group of ovarian epithelial cell carcinomas, we found the positive staining intensity of Notch1, Notch2, Jagged1, STAT3 and Epithelial‐mesenchymal transition (EMT) proteins were lower in a platinum‐resistant group. The DDP‐resistant ovarian cancer cell line (C13K) had a higher IC50 of DDP than its parental cell line (OV2008) (P < 0.05) and acquired an EMT phenotype and invasive characteristics. Inhibiting or knockdown of Jagged1 expression could not only reduce its capacity of migration and invasion but also reverse EMT and down‐regulate the expression of serine 727‐phosphorylated STAT3 (pS727) at the protein level but not total STAT3 or tyrosine 705‐phosphorylated STAT3 (pY705) in C13K cells. Furthermore, it was found that crosstalk between the Jagged1/Notch and JAK/STAT3 signalling pathways were involved in Jagged1‐promoting EMT in C13K cells. Experiments in vivo showed a reduced micrometastatic tumour burden in the lung, liver and spleen of mice implanted with C13K cells with knocked‐down Jagged1 compared with mice implanted with control cells. All of these results demonstrate that Jagged1 can crosstalk with the JAK/STAT3 pathway, and they all cooperate to promote the aberrant occurrence of EMT, further reinforcing the abilities of invasion and migration of platinum‐resistant ovarian cancer in vivo and in vitro.

Net Survival of Elderly Patients with Gynecological Cancer Aged Over 75 Years in 2006-2008

Background:

The number of elderly patients with gynecological cancer in Japan is increasing in line with the aging of society. However, little has been reported on the survival of elderly patients aged 75 or older with gynecological cancer in Japan.

Methods:

To clarify survival in women aged 75 years or older with gynecological cancer, we analyzed data of 4,089 gynecological cancer cases (cervical cancer, 1,309 cases; endometrial cancer, 1,319 cases; and ovarian cancer, 1,461 cases) in patients aged 75 or older from 21 population-based cancer registries in Japan, diagnosed in 2006-2008. We calculated the net survival (NS) of younger (75-79 years old), older (80-84 years old) and the oldest age group (85-99 years old). We also calculated NS stratified by extent of disease and histological type.

Results:

Five-year NS of cervical cancer patients was 54.5% in the younger age group, 40.8% in the older age group and 28.2% in the oldest age group. Five-year NS of endometrial cancer patients was 64.5%, 51.6% and 39.0% in the younger, older and oldest age groups, respectively. Five-year NS of ovarian cancer was 34.7%, 18.8% and 8.3%, respectively.

Conclusion:

We estimated NS in elderly patients aged 75 years or older with gynecological cancers in Japan using data from population-based cancer registries.

High Expression of HLA-G in Ovarian Carcinomatosis: The Role of Interleukin-1β

The present study focuses on the influence of the tumor microenvironment on the expression of HLA-G in ovarian cancer and its impact on immune cells. We used carcinomatosis fluids (n = 16) collected from patients diagnosed with epithelial ovarian cancer, detected by an increase in CA125 levels. Our results indicate that HLA-G is expressed by 1) ascitic cell clusters, 2) stromal cells (hospicells) extracted from cancer cell clusters, and 3) cancer cell lines and tumor cells. The origin of HLA-G was linked to inflammatory cytokines present in the cancer microenvironment. In parallel, the ascitic fluid of patients with ovarian cancer contains soluble HLA-G (sHLA-G). The mesothelial cell layer and submesothelial tissues, as well as the immune cell infiltrate, do not secrete HLA-G. In contrast, sHLA-G is absorbed by peritoneal tissues along with mesothelial layers as well as immune cell infiltrates. We demonstrated that interleukin-1β along with TGF-β can be a major HLA-G-inducing factor that upregulates HLA-G expression through the NF-κB pathway. The level of HLA-G in ascites correlated positively with the expression of T regulatory (T-regs) cells, while it negatively correlated with the expression of natural killer and memory cells in tumor-infiltrating immune cells. In conclusion, the production of HLA-G is associated with the presence of inflammatory cytokines and is strongly correlated with microenvironment tolerant cells such as T-regs and diminution of NK and memory T cells.

Next-generation sequencing-based genomic profiling analysis reveals novel mutations for clinical diagnosis in Chinese primary epithelial ovarian cancer patients

BACKGROUND

Ovarian cancer (OC) is one of the most malignant gynecological tumors, associated with excess death rate (50-60%) in ovarian cancer patients. Particularly, among newly occurred ovarian cancer patients, 70% of clinical cases are diagnosed at the advanced stage, which definitely delay the timely treatment and lead to high mortality rate within 5 years post diagnosis. Therefore, identification of sensitive gene markers, as well as development of reliable genetic diagnosis, are important for the early detection and precise therapy for OC patients. This study aims to identify novel genetic mutations and develop a feasible clinical approach for early OC diagnosis.

METHODS

The OC tissue-derived DNA sample was acquired from 31 OC patients, and the somatic gene mutations will be identified after comparison with normal samples, using Genome-wide analysis and next-generation sequencing.

RESULTS

A total of 463 somatic mutations, which were considered as potential pathogenic sites, were assigned to 473 genes. Among them, 15 genes (TP53, TTN, MUC16, OR4N2, BRCA1, CAD, CCDC129, INSR, NAV3, NELL2, NRAS, OBSCN, PGLYRP4, RBM15B and TRPC7) were mutated on at least two sites. These genes were mapped to RNA sequencing (RNAseq) data, and a total of 117 genes had an absolute fold- change ≥ 2 and p ≤ 0.01. Five genes were mutated in at least two OC patients. Gene ontology (GO) classification indicated that a majority of genes participated in biological processes. Kyoto Enrichment of Genes and Genomes (KEGG) enrichment pathway analysis revealed that the genes were mainly involved in the regulation of metabolic signaling pathways.

CONCLUSIONS

Taken together, this study identified several novel genetic alterations pathway for early clinical diagnosis and provided abundant information for understanding molecular mechanisms of the OC occurrence and development.

Integration of Two In-depth Quantitative Proteomics Approaches Determines the Kallikrein-related Peptidase 7 (KLK7) Degradome in Ovarian Cancer Cell Secretome

Kallikrein-related peptidase 7 (KLK7) is a serine peptidase that is over expressed in ovarian cancer. In vitro functional analyses have suggested KLK7 to play a cancer progressive role, although monitoring of KLK7 expression has suggested a contradictory protective role for KLK7 in ovarian cancer patients. In order to help delineate its mechanism of action and thereby the functional roles, information on its substrate repertoire is crucial. Therefore, in this study a quantitative proteomics approach-PROtein TOpography and Migration Analysis Platform (PROTOMAP)-coupled with SILAC was used for in-depth analysis of putative KLK7 substrates from a representative ovarian cancer cell line, SKOV-3, secreted proteins. The Terminal Amine Isotopic Labeling of Substrates (TAILS) approach was used to determine the exact cleavage sites and to validate qPROTOMAP-identified putative substrates. By employing these two technically divergent approaches, exact cleavage sites on 16 novel putative substrates and two established substrates, matrix metalloprotease (MMP) 2 and insulin growth factor binding protein 3 (IGFBP3), were identified in the SKOV-3 secretome. Eight of these substrates were also identified on TAILS analysis of another ovarian cancer cell (OVMZ-6) secretome, with a further seven OVMZ-6 substrates common to the SKOV-3 qPROTOMAP profile. Identified substrates were significantly associated with the common processes of cell adhesion, extracellular matrix remodeling and cell migration according to the gene ontology (GO) biological process analysis. Biochemical validation supports a role for KLK7 in directly activating pro-MMP10, hydrolysis of IGFBP6 and cleavage of thrombospondin 1 with generation of a potentially bioactive N-terminal fragment. Overall, this study constitutes the most comprehensive analysis of the putative KLK7 degradome in any cancer to date, thereby opening new avenues for KLK7 research.

BTB and CNC homology 1 (Bach1) promotes human ovarian cancer cell metastasis by HMGA2-mediated epithelial-mesenchymal transition

Transcriptional factor BTB and CNC homology 1 (Bach1) has been linked to tumor progression and metastasis, but the mechanisms underlying the effects of Bach1 on tumor growth and metastasis are largely uncharacterized. Here, we report that Bach1 expression was significantly higher in human epithelial ovarian cancer (EOC) tissues than in normal ovarian tissues and that higher levels of Bach1 were associated with tumor stage and poorer overall and progression-free survival. We found that Bach1 enhanced the expression of epithelial-mesenchymal transition (EMT) genes, including Slug and Snail, and promoted cell migration by recruiting HMGA2 in the human EOC cell line A2780. Bach1 overexpression enhanced and Bach1 knockout reduced the expression of Slug and the metastasis of EOC cells in a tumor metastasis mouse model. Bach1 expression was positively correlated with Slug and HMGA2 expression in human ovarian cancer tissues. In addition, Bach1 activated p-AKT and p-p70S6K, increased the expression of cyclin D1, and promoted the growth of ovarian cancer cells in vitro and tumor xenografts in vivo. Together, our findings reveal that Bach1 enhances tumor growth and recruits HMGA2 to promote EMT and ovarian cancer metastasis.

Development of nanoparticulate systems with action in breast and ovarian cancer: nanotheragnostics

The use of nanoparticulate systems with action in breast and ovarian cancer has been highlighted in recent years as an alternative to increasing the therapeutic index of conventional anticancer drugs. Thus, nanoparticles have advantageous characteristics in the treatment of cancer. Several nanocarriers of drugs and nanoparticles are described in the literature. The pharmacokinetics of the drugs can be modified by the use of nanocarriers, which in turn facilitate the specific delivery of the drug to the tumour cell. Therefore, the present work is a review that examines some nanosystems with nanoparticles for action in the treatment of breast cancer and ovarian cancer.

Betacellulin induces Slug-mediated down-regulation of E-cadherin and cell migration in ovarian cancer cells

Epithelial ovarian cancer is the leading cause of death among gynaecological cancers. Previous studies have demonstrated that epidermal growth factor receptor (EGFR) ligands can induce ovarian cancer cell invasion by down-regulating E-cadherin. Betacellulin is a unique member of the EGF family. It is overexpressed in a variety of cancers and is associated with reduced survival. However, the biological functions and clinical significance of betacellulin in ovarian cancer remain unknown. In the current study, we tested the hypothesis that betacellulin induces ovarian cancer cell migration by suppressing E-cadherin expression. Treatment of SKOV3 and OVCAR5 ovarian cancer cell lines with betacellulin down-regulated E-cadherin, but not N-cadherin. In addition, betacellulin treatment increased the expression of Snail and Slug, and these effects were completely blocked by pre-treatment with EGFR inhibitor AG1478. Interestingly, only knockdown of Slug reversed the down-regulation of E-cadherin by betacellulin. Betacellulin treatment induced the activation of both the MEK-ERK and PI3K-Akt signaling pathways, and it also significantly increased ovarian cancer cell migration. Importantly, the effects of betacellulin on E-cadherin, Slug and cell migration were attenuated by pre-treatment with either U0126 or LY294002. Our results suggest that betacellulin induces ovarian cancer migration and Slug-dependent E-cadherin down-regulation via EGFR-mediated MEK-ERK and PI3K-Akt signaling.

Genetic variants as ovarian cancer first-line treatment hallmarks: A systematic review and meta-analysis

BACKGROUND

The potential predictive value of genetic polymorphisms in ovarian cancer first-line treatment is inconsistently reported. We aimed to review ovarian cancer pharmacogenetic studies to update and summarize the available data and to provide directions for further research.

METHODS

A systematic review followed by a meta-analysis was conducted on cohort studies assessing the involvement of genetic polymorphisms in ovarian cancer first-line treatment response retrieved through a MEDLINE database search by November 2016. Studies were pooled and summary estimates and 95% confidence intervals (CI) were calculated using random or fixed-effects models as appropriate.

RESULTS

One hundred and forty-two studies gathering 106871 patients were included. Combined data suggested that GSTM1-null genotype patients have a lower risk of death compared to GSTM1-wt carriers, specifically in advanced stages (hazard ratio (HR), 0.68; 95% CI, 0.48-0.97) and when submitted to platinum-based chemotherapy (aHR, 0.61; 95% CI, 0.39-0.94). ERCC1 rs11615 and rs3212886 might have also a significant impact in treatment outcome (aHR, 0.67; 95% CI, 0.51-0.89; aHR, 1.28; 95% CI, 1.01-1.63, respectively). Moreover, ERCC2 rs13181 and rs1799793 showed a distinct ethnic behavior (Asians: aHR, 1.41; 95% CI, 0.80-2.49; aHR, 1.07; 95% CI, 0.62-1.86; Caucasians: aHR, 0.10; 95% CI, 0.01-0.96; aHR, 0.18; 95% CI, 0.05-0.68, respectively).

CONCLUSION(S)

The definition of integrative predictive models should encompass genetic information, especially regarding GSTM1 homozygous deletion. Justifying additional pharmacogenetic investigation are variants in ERCC1 and ERCC2, which highlight the DNA Repair ability to ovarian cancer prognosis. Further knowledge could aid to understand platinum-treatment failure and to tailor chemotherapy strategies.

Autophagy inhibition reduces chemoresistance and tumorigenic potential of human ovarian cancer stem cells

Epithelial ovarian cancer (EOC) is one of the most malignant gynecological tumors with a high mortality rate owing to tumor relapse after anticancer therapies. It is widely accepted that a rare tumor cell population, known as cancer stem cells (CSC), is responsible for tumor progression and relapse; intriguingly, these cells are able to survive nutrient starvation (such as in vitro culture in the absence of glucose) and chemotherapy treatment. Recent data also indicated that chemotherapy resistance is associated with autophagy activation. We thus decided to investigate both in vitro and in vivo the autophagic activity and the effects of the perturbation of this pathway in CSC isolated from EOC ascitic effusions. Ovarian CSC, identified according to their CD44/CD117 co-expression, presented a higher basal autophagy compared with the non-stem counterpart. Inhibition of this pathway, by in vitro chloroquine treatment or CRISPR/Cas9 ATG5 knockout, impaired canonical CSC properties, such as viability, the ability to form spheroidal structures in vitro, and in vivo tumorigenic potential. In addition, autophagy inhibition showed a synergistic effect with carboplatin administration on both in vitro CSC properties and in vivo tumorigenic activity. On the whole, these results indicate that the autophagy process has a key role in CSC maintenance; inhibition of this pathway in combination with other chemotherapeutic approaches could represent a novel effective strategy to overcome drug resistance and tumor recurrence.

Do tumor-infiltrating lymphocytes really indicate favorable prognosis in epithelial ovarian cancer?

OBJECTIVE

The aim of this study is to evaluate the impact of lymphocyte infiltration on prognostic parameters, recurrence and survival in ovarian cancer.

STUDY DESIGN

Sixty-two patients who were primarily operated for epithelial ovarian carcinoma between 1997 and 2008 were included. CD3, CD4, CD8, CD20 and FoxP3 expressions were evaluated immunohistochemically on sections obtained from paraffin-embedded tissues.

RESULTS

Median follow up was 87 months. In whole cohort, CD3+ and CD8+ T lymphocyte infiltrations were significantly higher in patients with high-grade tumors, advanced stage tumors and the patients with omental metastasis (for CD3 p=0.0001, p=0.029, p=0.016; for CD8 p=0.044, p=0.002, p=0.046, respectively). DFS was significantly lower among patients with CD8+ T lymphocytes with regard to patients who did not have CD8+ T lymphocyte infiltration (p=0.028). In univariate analysis, presence of CD8 cytotoxic T lymphocyte infiltration (p=0.03), stage (0.0001), tumor grade (p=0.007), omental metastasis (p=0.0001) and lymph node metastasis (p=0.0001) were significant risk factors for recurrence. But in multivariate analysis, only stage [HR: 116.6 (95% CI: 13.09-1039.45) (p=0.0001)] was found as an independent risk factor for recurrence.

CONCLUSION

CD3+ and CD8+ T lymphocyte infiltrations were related with advanced stage, high-grade tumor and the omental metastasis in ovarian cancer. DFS was significantly shorter in patients with CD8+ T lymphocyte infiltration. CD3+ and CD8+ T lymphocyte infiltrations were related with poor prognosis in ovarian cancer.

Tumor Staging and Grading: A Primer

Cancer staging and grading are used to predict the clinical behavior of malignancies, establish appropriate therapies, and facilitate exchange of precise information between clinicians. The internationally accepted criterion for cancer staging, the tumor-node-metastasis (TNM) system, includes: (1) tumor size and local growth (T), (2) extent of lymph node metastases (N), and (3) occurrence of distant metastases (M). Clinical stage is established before initiation of therapy and is determined by physical examination, laboratory findings, and imaging studies. Pathologic stage is determined following surgical exploration of disease and histologic examination of tissue. The TNM classification system has evolved over 70 years to accommodate increasing knowledge about cancer biology. Molecular technologies such as genomic and proteomic profiling of tumors could eventually be incorporated into the TNM staging system. This chapter describes the current TNM system using breast, lung, ovarian, and prostate cancer examples.

Resveratrol and acetyl-resveratrol modulate activity of VEGF and IL-8 in ovarian cancer cell aggregates via attenuation of the NF-κB protein

Background

Key features of advanced ovarian cancer include metastasis via cell clusters in the abdominal cavity and increased chemoresistance. Resveratrol and derivatives of resveratrol have been shown to have antitumour properties. The purpose of this study was to investigate the effect of resveratrol and acetyl-resveratrol on 3D cell aggregates of ovarian cancer, and establish if NF-κB signalling may be a potential target.

Methods

Poly-HEMA coated wells were used to produce 3D aggregates of two ovarian cancer cell lines, SKOV-3 and OVCAR-5. The aggregates were exposed to 10, 20 or 30 μM resveratrol or acetyl-resveratrol for 2, 4 or 6 days. Cell growth and metabolism were measured then ELISA, western blot and immunofluorescence were utilised to evaluate VEGF, IL-8 and NF-κB levels.

Results

Resveratrol and acetyl-resveratrol reduced cell growth and metabolism of SKOV-3 aggregates in a dose- and time-dependent manner. After 6 days all three doses of both compounds inhibited cell growth. This growth inhibition correlated with the attenuated secretion of VEGF and a decrease of NF-κB protein levels. Conversely, the secretion of IL-8 increased with treatment. The effects of the compounds were limited in OVCAR-5 cell clusters.

Conclusions

The results suggest that resveratrol and its derivative acetyl-resveratrol may inhibit in vitro 3D cell growth of certain subtypes of ovarian cancer, and growth restriction may be associated with the secretion of VEGF under the control of the NF-κB protein.

N-glycan MALDI Imaging Mass Spectrometry on Formalin-Fixed Paraffin-Embedded Tissue Enables the Delineation of Ovarian Cancer Tissues

Ovarian cancer is a fatal gynaecological malignancy in adult women with a five-year overall survival rate of only 30%. Glycomic and glycoproteomic profiling studies have reported extensive protein glycosylation pattern alterations in ovarian cancer. Therefore, spatio-temporal investigation of these glycosylation changes may unearth tissue-specific changes that occur in the development and progression of ovarian cancer. A novel method for investigating tissue-specific N-linked glycans is using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) on formalin-fixed paraffin-embedded (FFPE) tissue sections that can spatially profile N-glycan compositions released from proteins in tissue-specific regions. In this study, tissue regions of interest (e.g. tumor, stroma, adipose tissue and necrotic areas) were isolated from FFPE tissue sections of advanced serous ovarian cancers (n = 3). PGC-LC-ESI-MS/MS and MALDI-MSI were used as complementary techniques to firstly generate structural information on the tissue-specific glycans in order to then obtain high resolution images of the glycan structure distribution in ovarian cancer tissue. The N-linked glycan repertoires carried by the proteins in these tissue regions were structurally characterized for the first time in FFPE ovarian cancer tissue regions, using enzymatic peptide-N-glycosidase F (PNGase F) release of N-glycans. The released glycans were analyzed by porous graphitized carbon liquid chromatography (PGC-LC) and collision induced electrospray negative mode MS fragmentation analysis. The N-glycan profiles identified by this analysis were then used to determine the location and distribution of each N-glycan on FFPE ovarian cancer sections that were treated with PNGase F using high resolution MALDI-MSI. A tissue-specific distribution of N-glycan structures identified particular regions of the ovarian cancer sections. For example, high mannose glycans were predominantly expressed in the tumor tissue region whereas complex/hybrid N-glycans were significantly abundant in the intervening stroma. Therefore, tumor and non-tumor tissue regions were clearly demarcated solely on their N-glycan structure distributions.

Whole Reproductive System Non-Negative Matrix Factorization Mass Spectrometry Imaging of an Early-Stage Ovarian Cancer Mouse Model

High-grade serous carcinoma (HGSC) is the most common and deadliest form of ovarian cancer. Yet it is largely asymptomatic in its initial stages. Studying the origin and early progression of this disease is thus critical in identifying markers for early detection and screening purposes. Tissue-based mass spectrometry imaging (MSI) can be employed as an unbiased way of examining localized metabolic changes between healthy and cancerous tissue directly, at the onset of disease. In this study, we describe MSI results from Dicer-Pten double-knockout (DKO) mice, a mouse model faithfully reproducing the clinical nature of human HGSC. By using non-negative matrix factorization (NMF) for the unsupervised analysis of desorption electrospray ionization (DESI) datasets, tissue regions are segregated based on spectral components in an unbiased manner, with alterations related to HGSC highlighted. Results obtained by combining NMF with DESI-MSI revealed several metabolic species elevated in the tumor tissue and/or surrounding blood-filled cyst including ceramides, sphingomyelins, bilirubin, cholesterol sulfate, and various lysophospholipids. Multiple metabolites identified within the imaging study were also detected at altered levels within serum in a previous metabolomic study of the same mouse model. As an example workflow, features identified in this study were used to build an oPLS-DA model capable of discriminating between DKO mice with early-stage tumors and controls with up to 88% accuracy.

Improvement of a predictive model in ovarian cancer patients submitted to platinum-based chemotherapy: implications of a GST activity profile

PURPOSE

The success of chemotherapy in ovarian cancer (OC) is directly associated with the broad variability in platinum response, with implications in patients survival. This heterogeneous response might result from inter-individual variations in the platinum-detoxification pathway due to the expression of glutathione-S-transferase (GST) enzymes. We hypothesized that GSTM1 and GSTT1 polymorphisms might have an impact as prognostic and predictive determinants for OC.

METHODS

We conducted a hospital-based study in a cohort of OC patients submitted to platinum-based chemotherapy. GSTM1 and GSTT1 genotypes were determined by multiplex PCR.

RESULTS

GSTM1-null genotype patients presented a significantly longer 5-year survival and an improved time to progression when compared with GSTM1-wt genotype patients (log-rank test, P = 0.001 and P = 0.013, respectively). Multivariate Cox regression analysis indicates that the inclusion of genetic information regarding GSTM1 polymorphism increased the predictive ability of risk of death after OC platinum-based chemotherapy (c-index from 0.712 to 0.833). Namely, residual disease (HR, 4.90; P = 0.016) and GSTM1-wt genotype emerged as more important predictors of risk of death (HR, 2.29; P = 0.039; P = 0.036 after bootstrap). No similar effect on survival was observed regarding GSTT1 polymorphism, and there were no statistically significant differences between GSTM1 and GSTT1 genotypes and the assessed patients' clinical-pathological characteristics.

CONCLUSION

GSTM1 polymorphism seems to have an impact in OC prognosis as it predicts a better response to platinum-based chemotherapy and hence an improved survival. The characterization of the GSTM1 genetic profile might be a useful molecular tool and a putative genetic marker for OC clinical outcome.

Sensitization of ovarian cancer cells to cisplatin by gold nanoparticles

Recently we reported that gold nanoparticles (AuNPs) inhibit ovarian tumor growth and metastasis in mice by reversing epithelial-mesenchymal transition (EMT). Since EMT is known to confer drug resistance to cancer cells, we wanted to investigate whether anti-EMT property of AuNP could be utilized to sensitize ovarian cancer cells to cisplatin. Herein, we report that AuNPs prevent cisplatin-induced acquired chemoresistance and stemness in ovarian cancer cells and sensitize them to cisplatin. AuNPs inhibit cisplatin induced EMT, decrease the side population cells and key stem cell markers such as ALDH1, CD44, CD133, Sox2, MDR1 and ABCG2 in ovarian cancer cells. Mechanistically, AuNPs prevent cisplatin-induced activation of Akt and NF-κB signaling axis in ovarian cancer cells that are critical for EMT, stem cell maintenance and drug resistance. In vivo, AuNPs sensitize orthotopically implanted ovarian tumor to a low dose of cisplatin and significantly inhibit tumor growth via facilitated delivery of both AuNP and cisplatin. These findings suggest that by depleting stem cell pools and inhibiting key molecular pathways gold nanoparticles sensitize ovarian cancer cells to cisplatin and may be used in combination to inhibit tumor growth and metastasis in ovarian cancer.

Isoalantolactone induces autophagic cell death in SKOV₃ human ovarian carcinoma cells via upregulation of PEA-15

We investigated the effects of isoalantolactone on cell growth inhibition and underlying cell death mechanisms in SKOV3 human ovarian cancer cells. The effects of isoalantolactone on cell proliferation and cell cycle were examined by EdU incorporation assay and DNA content assay. Western blotting was performed to determine the protein expression effects of isoalantolactone on cell cycle‑related proteins, autophagic regulators and PEA‑15. Autophagic vacuoles were observed by acridine orange staining. PEA‑15 knockdown by siRNA was used to confirm that PEA‑15 was involved in isoalantolactone‑induced autophagy of SKOV3 cells. Isoalantolactone inhibited the viability and proliferation of SKOV3 cells in a dose‑ and time‑dependent fashion. Isoalantolactone induced cell cycle arrest at G2/M phase and decreased the expression of cell cycle‑related proteins cyclin B1 and CDK1 in SKOV3 cells. Accordingly, isoalantolactone also induced SKOV3 cell autophagy via accumulation of autophagic vacuoles in the cytoplasm, increased Beclin1 protein expression, and increased LC3 cleavage. Furthermore, we observed that isoalantolactone‑induced autophagy was through increased PEA‑15 expression and the phosphorylation of ERK, whereas less change was observed to autophagy on SKOV3 cells through PEA‑15 knockdown by siRNA. Isoalantolactone‑induced autophagic cell death was further confirmed by pretreatment with the autophagy inhibitor 3‑methyladenine (3‑MA). In conclusion, isoalantolactone induced cell cycle arrest and autophagy and inhibited cell proliferation of SKOV3 cells via the upregulated PEA‑15 expression and the phosphorylation of ERK.

Prognostic factors modifying the treatment-free interval in recurrent ovarian cancer

OBJECTIVES

While primary treatment for high-grade serous ovarian cancer tends to be uniform - maximal debulking and platinum/taxane adjuvant chemotherapy - there is little standardization of treatment in the recurrent setting beyond the exhaustive use of platinum therapies. Using secondary data from multiple centers participating in the Cancer Genome Atlas study (TCGA), we seek to characterize clinical features, timing and serial response data to provide empirical evidence for treatment expectations in the recurrent setting.

METHODS

We conducted a retrospective survival analysis of TCGA study primary and secondary patient chemotherapy regimens by characterizing the dynamics of 1119 lines of therapy comprising the treatment of 461 high-grade serous ovarian cancer patients. All patients with post-surgical drug therapy information from the TCGA database were included in this study.

RESULTS

A complete response to adjuvant therapy led to longer overall survival, but did not affect treatment free intervals (TFIs) after relapse of disease. A strong predictor of the TFI on the next treatment regimen was the previous TFI with a decaying effect. The number of previous treatments, of platinum treatments, and the length of time from surgery all have an exponentially decreasing effect on TFI. Re-treatment times appear to cluster at predictable times following surgery.

CONCLUSIONS

While patients experience a consistent reduction in TFI with increasing re-treatment, the initial adjuvant interval is unrelated to later interval lengths. Platinum re-treatment remained an effective option in patients typically thought to be platinum resistant and the timing of monitoring visits may drive overall re-treatment patterns.

FDG-PET/CT to predict optimal primary cytoreductive surgery in patients with advanced ovarian cancer: preliminary results

AIMS AND BACKGROUND

Primary cytoreductive surgery (CRS) has a significant impact on prognosis in epithelial ovarian cancer (EOC). Patient selection is important to recognize factors limiting optimal CRS and to avoid unnecessary aggressive surgical procedures. We evaluated the contribution of fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in the presurgical identification of disease sites that may preclude EOC cytoreducibility.

METHODS

Patients with suspected EOC underwent 18F-FDG-PET/CT within 20 days before debulking surgery. The PET/CT results were compared with surgical findings and postsurgery histopathology in order to assess the diagnostic value.

RESULTS

Between August 2013 and January 2014, 29 patients were evaluated. The histopathology showed 23 EOC and 6 benign tumors. The FDG-PET/CT was positive (maximum standardized uptake value [SUVmax] 11.3 ± 5.4) in 21/23 (91%) patients with EOC and provided 2 false-negatives (1 mucinous and 1 clear cell carcinoma; SUVmax ≤2.8). The FDG-PET/CT was true-negative (SUVmax 2.2 ± 1.6) in 4 out of 6 patients (67%). False-positive FDG-PET results were obtained in 2 cellular fibromas (SUVmax 4.8 and 5.6). The sensitivity, specificity, and accuracy of PET/CT to characterize ovarian masses were 91%, 67%, and 86%, respectively. Among the 21 FDG-PET/CT-positive EOC, we detected factors limiting optimal CRS in 6 cases (29%): 4 hepatic hilum infiltration and 2 root mesentery involvement, confirmed at surgical exploration. The FDG-PET did not find limiting factors in the remaining 15 patients (71%) in whom optimal CRS was obtained.

CONCLUSIONS

Fluorodeoxyglucose-PET/CT shows high sensitivity but suboptimal specificity in the characterization of ovarian masses. However, PET/CT may play a role in noninvasively selecting patients with EOC who can benefit from primary CRS.

Gynecologic oncologic imaging with PET/CT

FDG-PET/CT has been evaluated in a variety of gynecologic malignancies in a variety of settings and is approved by the Centers for Medicare & Medicaid Services for the initial and subsequent treatment strategies of these malignancies. Cervical cancer is typically very FDG avid, and FDG-PET/CT appears to be most valuable for initial staging, radiation therapy planning, and detection of recurrent disease. For ovarian cancer, the most value of FDG-PET/CT appears to be for detecting recurrent disease in the setting of rising CA-125 level and negative or equivocal anatomical imaging studies. Initial studies evaluating response to therapy are promising and further work in this area is needed. FDG uptake in both nonmalignant and physiological processes in the pelvis can make interpretation of FDG-PET/CT in this region challenging and knowledge of these entities and patterns can avoid misinterpretation. Some of the most common findings relate to the cyclic changes that occur as part of the menstrual cycle in premenopausal women. Mucinous tumors and low-volume or peritoneal carcinomatosis are causes of false-negative results on FDG-PET/CT studies. As new tracers are developed, comparisons with patient outcomes and standards of care (eg, FDG-PET/CT) will be needed.

Proteasome inhibition reverses hedgehog inhibitor and taxane resistance in ovarian cancer

The goal of this study was to determine whether combined targeted therapies, specifically those against the Notch, hedgehog and ubiquitin-proteasome pathways, could overcome ovarian cancer chemoresistance. Chemoresistant ovarian cancer cells were exposed to gamma-secretase inhibitors (GSI-I, Compound E) or the proteasome inhibitor bortezomib, alone and in combination with the hedgehog antagonist, LDE225. Bortezomib, alone and in combination with LDE225, was evaluated for effects on paclitaxel efficacy. Cell viability and cell cycle analysis were assessed by MTT assay and propidium iodide staining, respectively. Proteasome activity and gene expression were determined by luminescence assay and qPCR, respectively. Studies demonstrated that GSI-I, but not Compound E, inhibited proteasome activity, similar to bortezomib. Proteasome inhibition decreased hedgehog target genes (PTCH1, GLI1 and GLI2) and increased LDE225 sensitivity in vitro. Bortezomib, alone and in combination with LDE225, increased paclitaxel sensitivity through apoptosis and G2/M arrest. Expression of the multi-drug resistance gene ABCB1/MDR1 was decreased and acetylation of α-tubulin, a marker of microtubule stabilization, was increased following bortezomib treatment. HDAC6 inhibitor tubastatin-a demonstrated that microtubule effects are associated with hedgehog inhibition and sensitization to paclitaxel and LDE225. These results suggest that proteasome inhibition, through alteration of microtubule dynamics and hedgehog signaling, can reverse taxane-mediated chemoresistance.

Tetranectin positive expression in tumour tissue leads to longer survival in Danish women with ovarian cancer. Results from the 'Malova' ovarian cancer study

The primary objective of this study was to analyse Tetranectin (TN) expression in tumour tissues and TN serum concentration in 758 women with epithelial ovarian tumours. The second was to evaluate, whether TN tissue expression levels correlate with clinico-pathological parameters and prognosis of the disease. Using tissue arrays we analysed the expression levels in tissues from 166 women with borderline ovarian tumours (BOTs) and 592 women with ovarian cancer (OC). A panel of three antibodies was used for immunohistochemistry: a polyclonal and two monoclonal antibodies. Serum TN was measured using the polyclonal antibody A-371. Univariate survival analyses stratified for chemotherapy showed that positive tissue TN as demonstrated by the polyclonal antibody indicated a significantly longer overall survival (OS) (p = 0.0001) as well as cancer specific survival (CSS) (p < 0.0001). High serum TN was likewise found to imply longer OS (p < 0.0001) and CSS (p < 0.0001), whereas tissue staining with the two monoclonal antibodies failed to demonstrate any significant correlation with either survival type. Univariate Kaplan-Meier survival analysis performed on all OC cases showed a significantly longer OS (p = 0.0009) and CSS (p = 0.0006) for women with TN positive tumour tissue and in women with high serum TN levels (p < 0.0001 for both). However, in the multivariate Cox regression analysis, only serum TN was found to be an independent prognostic factor for OS (p = 0.01) and not for CSS (p = 0.08). In conclusion, our results predict that a positive TN expression of both tumour tissue and serum points to a more favourable outcome for OC patients.

CIAPIN1 targets Na⁺/H⁺ exchanger 1 to mediate MDA-MB-231 cells' metastasis through regulation of MMPs via ERK1/2 signaling pathway

Cytokine-induced antiapoptotic inhibitor 1 (CIAPIN1) was recently identified as an essential downstream effector of the Ras signaling pathway and has been confirmed to be closely associated with various malignant tumors. However, its potential role in regulating breast cancer metastasis remains unclear. Matrix metalloproteinases (MMPs) are a broad family of zinc-biding endopeptidases that participate in the extracellular matrix (ECM) degradation that accompanies cancer cell invasion, metastasis and angiogenesis. In this study, we found up-regulation of CIAPIN1 by lentiviral expression vector inhibited the migration, invasion and MMPs expression of MDA-MB-231 cells. Further, CIAPIN1 over-expression decreased NHE1 (Na(+)/H(+) exchanger 1) expression and ERK1/2 phosphorylation. Importantly, treating CIAPIN1 over-expressed MDA-MB-231 cells with the NHE1 specific inhibitor, Cariporide, further inhibited the metastatic capacity, MMPs expression and phosphorylated ERK1/2. Treatment with the MEK1 specific inhibitor, PD98059, induced nearly the same suppression of CIAPIN1 over-expression-dependent migration, invasion and MMPs expression as was observed with Cariporide. Further, Cariporide and PD98059 synergistically suppressed migration, invasion and MMPs expression of CIAPIN1 over-expressed MDA-MB-231 cells. Thus, our results revealed the mechanism by which CIAPIN1 targeted NHE1 to mediate migration and invasion of MDA-MB-231 cells through regulation of MMPs via ERK1/2 signaling pathway.

Glycoprofiling of cancer biomarkers: Label-free electrochemical lectin-based biosensors

Glycosylation of biomolecules is one of the most prevalent post- and co-translational modification in a human body, with more than half of all human proteins being glycosylated. Malignant transformation of cells influences glycosylation machinery resulting in subtle changes of the glycosylation pattern within the cell populations as a result of cancer. Thus, an altered terminal glycan motif on glycoproteins could provide a warning signal about disease development and progression and could be applied as a reliable biomarker in cancer diagnostics. Among all highly effective glycoprofiling tools, label-free electrochemical impedance spectroscopy (EIS)-based biosensors have emerged as especially suitable tool for point-of-care early-stage cancer detection. Herein, we highlight the current challenges in glycoprofiling of various cancer biomarkers by ultrasensitive impedimetric-based biosensors with low sample consumption, low cost fabrication and simple miniaturization. Additionally, this review provides a short introduction to the field of glycomics and lectinomics and gives a brief overview of glycan alterations in different types of cancer.

Nidogen-1: a candidate biomarker for ovarian serous cancer

OBJECTIVE

Effective biomarkers for early detection of ovarian cancer are needed. Our study previously showed that basement membrane protein, nidogen-1 plasma level was significantly increased in ovarian cancer patients. This study aimed to examine the plasma levels of nidogen-1 in a large patient population to evaluate its effectiveness in ovarian serous carcinoma and expression in tumor tissues.

METHODS

The concentration of nidogen-1 in circulating plasma specimens of 265 ovarian serous cancer patients and 98 healthy individuals were assayed by enzyme linked immunosorbent assay. The medical records of 265 ovarian serous cancer cases were reviewed retrospectively. The expression status of nidogen-1 in tumor tissues of 44 ovarian serous carcinoma patients was examined by immunohistochemical analysis. For statistical analysis, we used the Mann-Whitney U test, Fisher's exact test and receiver operating characteristic.

RESULTS

Protein levels of nidogen-1 were considerably raised in the plasma from ovarian serous cancer patients compared with those in healthy controls (P < 0.001), especially elevated in patients with advanced stage and those received neoadjuvant chemotherapy followed by interval debulking surgery. However, it was irrelevant to the grade, chemotherapy sensitivity or residual tumor of the ovarian serous carcinoma cases investigated (P > 0.05). Receiver operating characteristic curve analysis for nidogen-1 showed that it could discriminate patients with ovarian serous carcinomas from healthy controls [areas under the curve (AUC): 0. 65, 95%CI, 0.59-0.71], but CA125 was superior (AUC: 0. 98, 95%CI, 0.96-0.99). The immunohistochemical staining result showed that nidogen-1 protein was localized both in the cancer cell cytoplasm and intercellular substance, mainly expressed in extracellular matrix of ovarian serous carcinoma tissues (the positive rate was 77.3%).

CONCLUSIONS

Our study suggests that plasma nidogen-1 may be used as a diagnostic biomarker for ovarian serous carcinoma and can reflect the tumor burden.

Deciphering the peptidome of urine from ovarian cancer patients and healthy controls

Background

Ovarian cancer (OvCa) is the most lethal gynecological malignancy. The emergence of high-throughput technologies, such as mass spectrometry, has allowed for a paradigm shift in the way we search for novel biomarkers. Urine-based peptidomic profiling is a novel approach that may result in the discovery of noninvasive biomarkers for diagnosing patients with OvCa. In this study, the peptidome of urine from 6 ovarian cancer patients and 6 healthy controls was deciphered.

Results

Urine samples underwent ultrafiltration and the filtrate was subjected to solid phase extraction, followed by fractionation using strong cation exchange chromatography. These fractions were analyzed using an Orbitrap mass spectrometer. Over 4600 unique endogenous urine peptides arising from 713 proteins were catalogued, representing the largest urine peptidome reported to date. Each specimen was processed in triplicate and reproducibility at the protein (69-76%) and peptide (58-63%) levels were noted. More importantly, over 3100 unique peptides were detected solely in OvCa specimens. One such promising biomarker was leucine-rich alpha-2-glycoprotein (LRG1), where multiple peptides were found in all urines from OvCa patients, but only one peptide was found in one healthy control urine sample.

Conclusions

Mining the urine peptidome may yield highly promising novel OvCa biomarkers.

Deciphering the ovarian cancer ascites fluid peptidome

Background

Conventional proteomic approaches have thus far been unable to identify novel serum biomarkers for ovarian cancer that are more sensitive and specific than the current clinically used marker, CA-125. Because endogenous peptides are smaller and may enter the circulation more easily than proteins, a focus on the low-molecular-weight region may reveal novel biomarkers with enhanced sensitivity and specificity. In this study, we deciphered the peptidome of ascites fluid from 3 ovarian cancer patients and 3 benign individuals (ascites fluid from patients with liver cirrhosis).

Results

Following ultrafiltration of the ascites fluids to remove larger proteins, each filtrate was subjected to solid phase extraction and fractionated using strong cation exchange chromatography. The resultant fractions were analyzed using an Orbitrap mass spectrometer. We identified over 2000 unique endogenous peptides derived from 259 proteins. We then catalogued over 777 peptides that were found only in ovarian cancer ascites. Our list of peptides found in ovarian cancer specimens includes fragments derived from the proteins vitronectin, transketolase and haptoglobin.

Conclusions

Peptidomics may uncover previously undiscovered disease-specific endogenous peptides that warrant further investigation as biomarkers for ovarian cancer.

Randomized reverse marker strategy design for prospective biomarker validation

We describe a novel study design for validating marker-based treatment strategies meant to select among possible therapeutic options using a biologic marker. Studying existing designs in realistic scenarios, we demonstrate that this design is more than four times more efficient for testing the interaction between a marker and its intended treatment. Our analysis employs a simple parametric framework that uncovers systematic biases in currently proposed designs and suggests how they may be accommodated or enumerated. In the context of markers for choosing a treatment for recurrent ovarian cancer, our proposal requires sample sizes on the order of recently completed phases II and III studies making validation studies for this clinical decision scenario viable.

Discrete mixture modeling to address genetic heterogeneity in time-to-event regression

MOTIVATION

Time-to-event regression models are a critical tool for associating survival time outcomes with molecular data. Despite mounting evidence that genetic subgroups of the same clinical disease exist, little attention has been given to exploring how this heterogeneity affects time-to-event model building and how to accommodate it. Methods able to diagnose and model heterogeneity should be valuable additions to the biomarker discovery toolset.

RESULTS

We propose a mixture of survival functions that classifies subjects with similar relationships to a time-to-event response. This model incorporates multivariate regression and model selection and can be fit with an expectation maximization algorithm, we call Cox-assisted clustering. We illustrate a likely manifestation of genetic heterogeneity and demonstrate how it may affect survival models with little warning. An application to gene expression in ovarian cancer DNA repair pathways illustrates how the model may be used to learn new genetic subsets for risk stratification. We explore the implications of this model for censored observations and the effect on genomic predictors and diagnostic analysis.

AVAILABILITY AND IMPLEMENTATION

R implementation of CAC using standard packages is available at https://gist.github.com/programeng/8620b85146b14b6edf8f Data used in the analysis are publicly available.

CD44 targets Na(+)/H(+) exchanger 1 to mediate MDA-MB-231 cells' metastasis via the regulation of ERK1/2

Background:

CD44, a transmembrane glycoprotein expressed in a variety of cells and tissues, has been implicated in tumour metastasis. But the molecular mechanisms of CD44-mediated tumour cell metastasis remain to be elucidated.

Methods:

The downregulation of CD44 was determined by immunofluorescence. Moreover, the motility of breast cancer cells was detected by wound-healing and transwell experiments. Then the spontaneous metastasis of CD44-silenced MDA-MB-231 cells was tested by histology with BALB/c nude mice.

Results:

A positive correlation between CD44 and Na⁺/H⁺ exchanger isoform 1 (NHE1) was found in two breast cancer cells. CD44 downregulation could inhibit the metastasis of MDA-MB-231 cells and the expressions of Na⁺/H⁺ exchanger 1. Moreover, CD44 overexpression upregulated the metastasis of MCF-7 cells, but the elevated metastatic ability was then inhibited by Cariporide. Interestingly, during these processes only the p-ERK1/2 was suppressed by CD44 downregulation and the expression of matrix metalloproteinases and metastatic capacity of MDA-MB-231 cells were greatly inhibited by the MEK1 inhibitor PD98059, which even had a synergistic effect with Cariporide. Furthermore, CD44 downregulation inhibits breast tumour outgrowth and spontaneous lung metastasis.

Conclusions:

Taken together, this work indicates that CD44 regulates the metastasis of breast cancer cells through regulating NHE1 expression, which could be used as a novel strategy for breast cancer therapy.