Loss of microRNA-135b Enhances Bone Metastasis in Prostate Cancer and Predicts Aggressiveness in Human Prostate Samples

About 70% of advanced-stage prostate cancer (PCa) patients will experience bone metastasis, which severely affects patients' quality of life and progresses to lethal PCa in most cases. Hence, understanding the molecular heterogeneity of PCa cell populations and the signaling pathways associated with bone tropism is crucial. For this purpose, we generated an animal model with high penetrance to metastasize to bone using an intracardiac percutaneous injection of PC3 cells to identify PCa metastasis-promoting factors. Using genomic high-throughput analysis we identified a miRNA signature involved in bone metastasis that also presents potential as a biomarker of PCa progression in human samples. In particular, the downregulation of miR-135b favored the incidence of bone metastases by significantly increasing PCa cells' migratory capacity. Moreover, the PLAG1, JAKMIP2, PDGFA, and VTI1b target genes were identified as potential mediators of miR-135b's role in the dissemination to bone. In this study, we provide a genomic signature involved in PCa bone growth, contributing to a better understanding of the mechanisms responsible for this process. In the future, our results could ultimately translate into promising new therapeutic targets for the treatment of lethal PCa.

Targeted proteomics in urinary extracellular vesicles identifies biomarkers for diagnosis and prognosis of prostate cancer

Rapid and reliable diagnosis of prostate cancer (PCa) is highly desirable as current used methods lack specificity. In addition, identification of PCa biomarkers that can classify patients into high- and low-risk groups for disease progression at early stage will improve treatment decision-making. Here, we describe a set of protein-combination panels in urinary extracellular vesicles (EVs), defined by targeted proteomics and immunoblotting techniques that improve early non-invasive detection and stratification of PCa patients.We report a two-protein combination in urinary EVs that classifies benign and PCa patients (ADSV-TGM4), and a combination of five proteins able to significantly distinguish between high- and low-grade PCa patients (CD63-GLPK5-SPHM-PSA-PAPP). Proteins composing the panels were validated by immunohistochemistry assays in tissue microarrays (TMAs) confirming a strong link between the urinary EVs proteome and alterations in PCa tissues. Moreover, ADSV and TGM4 abundance yielded a high diagnostic potential in tissue and promising TGM4 prognostic power. These results suggest that the proteins identified in urinary EVs distinguishing high- and low grade PCa are a reflection of histological changes that may be a consequence of their functional involvement in PCa development. In conclusion, our study resulted in the identification of protein-combination panels present in urinary EVs that exhibit high sensitivity and specificity for PCa detection and patient stratification. Moreover, our study highlights the potential of targeted proteomic approaches–such as selected reaction monitoring (SRM)–as diagnostic assay for liquid biopsies via urinary EVs to improve diagnosis and prognosis of suspected PCa patients.

E-cadherin: A determinant molecule associated with ovarian cancer progression, dissemination and aggressiveness

Ovarian cancer (OC) is the fifth cancer death cause in women worldwide. The malignant nature of this disease stems from its unique dissemination pattern. Epithelial-to-mesenchymal transition (EMT) has been reported in OC and downregulation of Epithelial cadherin (E-cadherin) is a hallmark of this process. However, findings on the relationship between E-cadherin levels and OC progression, dissemination and aggressiveness are controversial. In this study, the evaluation of E-cadherin expression in an OC tissue microarray revealed its prognostic value to discriminate between advanced- and early-stage tumors, as well as serous tumors from other histologies. Moreover, E-cadherin, Neural cadherin (N-cadherin), cytokeratins and vimentin expression was assessed in TOV-112, SKOV-3, OAW-42 and OV-90 OC cell lines grown in monolayers and under anchorage-independent conditions to mimic ovarian tumor cell dissemination, and results were associated with cell aggressiveness. According to these EMT-related markers, cell lines were classified as mesenchymal (M; TOV-112), intermediate mesenchymal (IM; SKOV-3), intermediate epithelial (IE; OAW-42) and epithelial (E; OV-90). M- and IM-cells depicted the highest migration capacity when grown in monolayers, and aggregates derived from M- and IM-cell lines showed lower cell death, higher adhesion to extracellular matrices and higher invasion capacity than E- and IE-aggregates. The analysis of E-cadherin, N-cadherin, cytokeratin 19 and vimentin mRNA levels in 20 advanced-stage high-grade serous human OC ascites showed an IM phenotype in all cases, characterized by higher proportions of N- to E-cadherin and vimentin to cytokeratin 19. In particular, higher E-cadherin mRNA levels were associated with cancer antigen 125 levels more than 500 U/mL and platinum-free intervals less than 6 months. Altogether, E-cadherin expression levels were found relevant for the assessment of OC progression and aggressiveness.

E-cadherin: A determinant molecule associated with ovarian cancer progression, dissemination and aggressiveness

Ovarian cancer (OC) is the fifth cancer death cause in women worldwide. The malignant nature of this disease stems from its unique dissemination pattern. Epithelial-to-mesenchymal transition (EMT) has been reported in OC and downregulation of Epithelial cadherin (E-cadherin) is a hallmark of this process. However, findings on the relationship between E-cadherin levels and OC progression, dissemination and aggressiveness are controversial. In this study, the evaluation of E-cadherin expression in an OC tissue microarray revealed its prognostic value to discriminate between advanced- and early-stage tumors, as well as serous tumors from other histologies. Moreover, E-cadherin, Neural cadherin (N-cadherin), cytokeratins and vimentin expression was assessed in TOV-112, SKOV-3, OAW-42 and OV-90 OC cell lines grown in monolayers and under anchorage-independent conditions to mimic ovarian tumor cell dissemination, and results were associated with cell aggressiveness. According to these EMT-related markers, cell lines were classified as mesenchymal (M; TOV-112), intermediate mesenchymal (IM; SKOV-3), intermediate epithelial (IE; OAW-42) and epithelial (E; OV-90). M- and IM-cells depicted the highest migration capacity when grown in monolayers, and aggregates derived from M- and IM-cell lines showed lower cell death, higher adhesion to extracellular matrices and higher invasion capacity than E- and IE-aggregates. The analysis of E-cadherin, N-cadherin, cytokeratin 19 and vimentin mRNA levels in 20 advanced-stage high-grade serous human OC ascites showed an IM phenotype in all cases, characterized by higher proportions of N- to E-cadherin and vimentin to cytokeratin 19. In particular, higher E-cadherin mRNA levels were associated with cancer antigen 125 levels more than 500 U/mL and platinum-free intervals less than 6 months. Altogether, E-cadherin expression levels were found relevant for the assessment of OC progression and aggressiveness.

E-cadherin: A determinant molecule associated with ovarian cancer progression, dissemination and aggressiveness

Ovarian cancer (OC) is the fifth cancer death cause in women worldwide. The malignant nature of this disease stems from its unique dissemination pattern. Epithelial-to-mesenchymal transition (EMT) has been reported in OC and downregulation of Epithelial cadherin (E-cadherin) is a hallmark of this process. However, findings on the relationship between E-cadherin levels and OC progression, dissemination and aggressiveness are controversial. In this study, the evaluation of E-cadherin expression in an OC tissue microarray revealed its prognostic value to discriminate between advanced- and early-stage tumors, as well as serous tumors from other histologies. Moreover, E-cadherin, Neural cadherin (N-cadherin), cytokeratins and vimentin expression was assessed in TOV-112, SKOV-3, OAW-42 and OV-90 OC cell lines grown in monolayers and under anchorage-independent conditions to mimic ovarian tumor cell dissemination, and results were associated with cell aggressiveness. According to these EMT-related markers, cell lines were classified as mesenchymal (M; TOV-112), intermediate mesenchymal (IM; SKOV-3), intermediate epithelial (IE; OAW-42) and epithelial (E; OV-90). M- and IM-cells depicted the highest migration capacity when grown in monolayers, and aggregates derived from M- and IM-cell lines showed lower cell death, higher adhesion to extracellular matrices and higher invasion capacity than E- and IE-aggregates. The analysis of E-cadherin, N-cadherin, cytokeratin 19 and vimentin mRNA levels in 20 advanced-stage high-grade serous human OC ascites showed an IM phenotype in all cases, characterized by higher proportions of N- to E-cadherin and vimentin to cytokeratin 19. In particular, higher E-cadherin mRNA levels were associated with cancer antigen 125 levels more than 500 U/mL and platinum-free intervals less than 6 months. Altogether, E-cadherin expression levels were found relevant for the assessment of OC progression and aggressiveness.

Exosome-like vesicles in uterine aspirates: a comparison of ultracentrifugation-based isolation protocols

Background

Uterine aspirates are used in the diagnostic process of endometrial disorders, yet further applications could emerge if its complex milieu was simplified. Exosome-like vesicles isolated from uterine aspirates could become an attractive source of biomarkers, but there is a need to standardize isolation protocols. The objective of the study was to determine whether exosome-like vesicles exist in the fluid fraction of uterine aspirates and to compare protocols for their isolation, characterization, and analysis.

Methods

We collected uterine aspirates from 39 pre-menopausal women suffering from benign gynecological diseases. The fluid fraction of 27 of those aspirates were pooled and split into equal volumes to evaluate three differential centrifugation-based procedures: (1) a standard protocol, (2) a filtration protocol, and (3) a sucrose cushion protocol. Characterization of isolated vesicles was assessed by electron microscopy, nanoparticle tracking analysis and immunoblot. Specifically for RNA material, we evaluate the effect of sonication and RNase A treatment at different steps of the protocol. We finally confirmed the efficiency of the selected methods in non-pooled samples.

Results

All protocols were useful to isolate exosome-like vesicles. However, the Standard procedure was the best performing protocol to isolate exosome-like vesicles from uterine aspirates: nanoparticle tracking analysis revealed a higher concentration of vesicles with a mode of 135 ± 5 nm, and immunoblot showed a higher expression of exosome-related markers (CD9, CD63, and CD81) thus verifying an enrichment in this type of vesicles. RNA contained in exosome-like vesicles was successfully extracted with no sonication treatment and exogenous nucleic acids digestion with RNaseA, allowing the analysis of the specific inner cargo by Real-Time qPCR.

Conclusion

We confirmed the existence of exosome-like vesicles in the fluid fraction of uterine aspirates. They were successfully isolated by differential centrifugation giving sufficient proteomic and transcriptomic material for further analyses. The Standard protocol was the best performing procedure since the other two tested protocols did not ameliorate neither yield nor purity of exosome-like vesicles. This study contributes to establishing the basis for future comparative studies to foster the field of biomarker research in gynecology.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-016-0935-4) contains supplementary material, which is available to authorized users.

Enabling Metabolomics Based Biomarker Discovery Studies Using Molecular Phenotyping of Exosome-Like Vesicles

Identification of sensitive and specific biomarkers with clinical and translational utility will require smart experimental strategies that would augment expanding the breadth and depth of molecular measurements within the constraints of currently available technologies. Exosomes represent an information rich matrix to discern novel disease mechanisms that are thought to contribute to pathologies such as dementia and cancer. Although proteomics and transcriptomic studies have been reported using Exosomes-Like Vesicles (ELVs) from different sources, exosomal metabolome characterization and its modulation in health and disease remains to be elucidated. Here we describe methodologies for UPLC-ESI-MS based small molecule profiling of ELVs from human plasma and cell culture media. In this study, we present evidence that indeed ELVs carry a rich metabolome that could not only augment the discovery of low abundance biomarkers but may also help explain the molecular basis of disease progression. This approach could be easily translated to other studies seeking to develop predictive biomarkers that can subsequently be used with simplified targeted approaches.

Abstract 4093: Cadherin “switch” and ovarian cancer: Studies using in vitro models and patient samples

Ovarian cancer (OC) is the 5th leading cause of cancer deaths in women worldwide due to late symptoms and its diagnosis at advanced stages. Epithelial to mesenchymal transition (EMT) is an important step in cancer invasion/metastasis and downregulation of Epithelial cadherin (Ecad) is a critical feature of this process. Ecad expression was evaluated in 100 OC tissue sections, finding a decreased Ecad signal along tumor stage, with highest expression in stage I/II (no invasive) and lowest in stage IV (invasive) tumors. These results are in agreement with previous reports showing reduced Ecad expression in correlation with poor prognosis in OC patients. In some cases, Ecad downregulation is accompanied by increased Neural cadherin (Ncad) expression and acquisition of migratory/mesenchymal features. Although this cadherin “switch” has been reported in OC, current data is inconclusive. Expression of Ecad, Ncad and other EMT markers was studied in 4 OC cell lines and according to their levels they were classified as epithelial (OV90), intermediate epithelial (OAW42), intermediate mesenchymal (SKOV3) and mesenchymal (TOV112) cells. The mechanisms underlying regulation of Ecad levels were evaluated by assessing expression of its transcriptional repressors Twist, Snail, Slug, Zeb1. Migration properties were also studied, being significantly higher in TOV112 and SKOV3 cells. It has been proposed that OC cells shed from the primary tumor aggregate as spheroids in the ascites, maintain cellular contacts and survive in suspension. To mimic ovarian tumor cell dissemination through the ascites and to evaluate the role of the cadherin “switch” in this process, cell lines were grown under anchorage-independent conditions. The aggregates number/area was analyzed, being the SKOV3 spheroids the most compacted. When Ecad, Ncad and EMT markers expression was determined similar findings were obtained when spheroids were compared to monolayers, suggesting an intrinsic cell gene expression pattern rather than a response to a cell culture growth condition. The OC spheroids survival was assessed by estimating cell death, finding a positive correlation between high Ncad levels and cell aggregates with low% cell death. Spheroid adhesion/dissemination in extracellular matrices and 3D-spheroid matrigel assays were done to assess invasion at a secondary site. Spheroids from cells with mesenchymal/intermediate mesenchymal phenotypes adhered to extracellular matrices and invaded more than cells with intermediate epithelial/epithelial phenotypes. Finally, Ecad/Ncad expression studies done on primary cultures derived from tumor and ascitic cells from patients with OC revealed a diminished Ecad and a higher Ncad expression in ascitic cells compared to primary tumor cells. Altogether, the data here presented reveals an association between OC cell aggressiveness and a mesenchymal-like molecular profile; and it depends on the expression of Ecad and Ncad markers.

Citation Format: Marina Rosso, Blanca Majem, Laura Devis, Lara Lapyckyj, Marta Llauradó, Lucía Lanau, María Florencia Abascal, María Laura Matos, María José Besso, Josep Castellví, Jose Luís Sanchez-Iglesias, Asunción Pérez-Benavente, Antonio Gil-Moreno, Jaume Reventós, Marina Rigau, Mónica Vazquez-Levin. Cadherin “switch” and ovarian cancer: Studies using in vitro models and patient samples. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4093. doi:10.1158/1538-7445.AM2015-4093

Urinary biomarkers for the detection of prostate cancer in patients with high-grade prostatic intraepithelial neoplasia

INTRODUCTION

High-grade prostatic intraepithelial neoplasia (HGPIN) is a recognized precursor stage of PCa. Men who present HGPIN in a first prostate biopsy face years of active surveillance including repeat biopsies. This study aimed to identify non-invasive prognostic biomarkers that differentiate early on between indolent HGPIN cases and those that will transform into actual PCa.

METHODS

We measured the expression of 21 candidate mRNA biomarkers using quantitative PCR in urine sediment samples from a cohort of 90 patients with initial diagnosis of HGPIN and a posterior follow up of at least two years. Uni- and multivariate statistical analyses were applied to analyze the candidate biomarkers and multiplex models using combinations of these biomarkers.

RESULTS

PSMA, PCA3, PSGR, GOLM, KLK3, CDH1, and SPINK1 behaved as predictors for PCa presence in repeat biopsies. Multiplex models outperformed (AUC = 0.81-0.86) the predictive power of single genes, including the FDA-approved PCA3 (AUC = 0.70). With a fixed sensitivity of 95%, the specificity of our multiplex models was of 41-58%, compared to the 30% of PCA3. The PPV of our models (30-38%) was also higher than the PPV of PCA3 (27%), suggesting that benign cases could be more accurately identified. Applying statistical models, we estimated that 33% to 47% of repeat biopsies could be prevented with a multiplex PCR model, representing an easy applicable and significant advantage over the current gold standard in urine sediment.

DISCUSSION

Using multiplex RTqPCR-based models in urine sediment it is possible to improve the current diagnostic method of choice (PCA3) to differentiate between benign HGPIN and PCa cases.

Well-differentiated mucinous uterine adenocarcinoma predominantly diagnosed as adenoma malignum: a case report with an immunohistochemical analysis

Adenoma malignum (AM), also referred to as "minimal deviation adenocarcinoma", is an extremely uncommon variant of highly-differentiated adenocarcinoma of the uterine cervix. The study presented herein describes a case of uterine AM found out after hysteroscopy. An early-stage, well-differentiated mucinous uterine adenocarcinoma was diagnosed post-operatively. A subsequent immunohistochemical assessment of a panel of antibodies was applied, in order to distinguish between female genital tract malignancies.

Biological properties of extracellular vesicles and their physiological functions

In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells. While intensive investigation has targeted the role of EVs in different pathological processes, for example, in cancer and autoimmune diseases, the EV-mediated maintenance of homeostasis and the regulation of physiological functions have remained less explored. Here, we provide a comprehensive overview of the current understanding of the physiological roles of EVs, which has been written by crowd-sourcing, drawing on the unique EV expertise of academia-based scientists, clinicians and industry based in 27 European countries, the United States and Australia. This review is intended to be of relevance to both researchers already working on EV biology and to newcomers who will encounter this universal cell biological system. Therefore, here we address the molecular contents and functions of EVs in various tissues and body fluids from cell systems to organs. We also review the physiological mechanisms of EVs in bacteria, lower eukaryotes and plants to highlight the functional uniformity of this emerging communication system.

Non-coding RNAs in saliva: emerging biomarkers for molecular diagnostics

Saliva is a complex body fluid that comprises secretions from the major and minor salivary glands, which are extensively supplied by blood. Therefore, molecules such as proteins, DNA, RNA, etc., present in plasma could be also present in saliva. Many studies have reported that saliva body fluid can be useful for discriminating several oral diseases, but also systemic diseases including cancer. Most of these studies revealed messenger RNA (mRNA) and proteomic biomarker signatures rather than specific non-coding RNA (ncRNA) profiles. NcRNAs are emerging as new regulators of diverse biological functions, playing an important role in oncogenesis and tumor progression. Indeed, the small size of these molecules makes them very stable in different body fluids and not as susceptible as mRNAs to degradation by ribonucleases (RNases). Therefore, the development of a non-invasive salivary test, based on ncRNAs profiles, could have a significant applicability to clinical practice, not only by reducing the cost of the health system, but also by benefitting the patient. Here, we summarize the current status and clinical implications of the ncRNAs present in human saliva as a source of biological information.

MicroRNAs as prognostic markers in ovarian cancer

Ovarian cancer (OC) is the most lethal gynecological malignancy among women. Over 70% of women with OC are diagnosed in advanced stages and most of these cases are incurable. Although most patients respond well to primary chemotherapy, tumors become resistant to treatment. Mechanisms of chemoresistance in cancer cells may be associated with mutational events and/or alterations of gene expression through epigenetic events. Although focusing on known genes has already yielded new information, previously unknown non-coding RNAs, such as microRNAs (miRNAs), also lead insight into the biology of chemoresistance. In this review we summarize the current evidence examining the role of miRNAs as biomarkers of response and survival to therapy in OC. Beside their clinical implications, we also discuss important differences between studies that may have limited their use as clinical biomarkers and suggest new approaches.

Abstract B15: Unveiling the mechanism of ovarian cancer dissemination through a comparative study among primary tumors, ascites and metastases

Introduction & Objectives: Epithelial ovarian cancer (OC) is the most lethal gynecological malignancy and the fifth cause of cancer deaths in women in the western world. Largely asymptomatic, OC is frequently detected at late stage (75-80%). Five-year survival rate for women with advanced stage disease is less than 20%, while the cure rate is almost 90% when are diagnosed at early stages. Epithelial OC metastasizes by direct extension from the ovary seeding the cells into the peritoneal wall and to neighbouring organs. Our aim is to study the OC dissemination comparing human paired ovarian primary tumors, ascites and metastases.

Material & Methods: Fresh ovarian primary tumor, ascites and peritoneal metastases from patients suffering advanced serous OC were collected at the surgery room and processed for further analysis. Formalin-fixed paraffin-embedded (FFPE) tissues were collected from the Pathology Department for further immunohistochemical analysis. Discovery phase: We determined the global gene expression profile of 5 fresh-paired samples (primary tumor, ascites and metastases) by microarray analysis. Validation phase: We analysed mRNA and protein levels from 10 unpaired fresh samples by RTqPCR and Western-blot, respectively. We further evaluated protein expression by immunohistochemistry from 10-paired tumor and metastasis FFPE-samples.

Results: GREM1 was shown to be upregulated in metastases versus ascites and in metastases versus primary tumors. FABP4 and INHBA were significantly overexpressed in metastases when compared to primary tumors. INHBA and FABP4 were validated at RNA and protein level, whereas GREM1 only at RNA level.

Conclusions: The present study highlights the role of previously unknown candidates in OC dissemination that might be used as tumor biomarkers, to clinically monitor the progression of the disease, or as target therapies, to block the OC dissemination.

Citation Format: Lucia Lanau, Marina Rigau, Blanca Majem, Tatiana Altadill, Josep Castellví, José-Luis Sánchez-Iglesias, Assumpció Pérez-Benavente, Silvia Cabrera, Angel García, Jordi Xercavins, Josep-Maria Del Campo, Antonio Gil-Moreno, Anna Ruiz, Jaume Reventós, Marta Llauradó. Unveiling the mechanism of ovarian cancer dissemination through a comparative study among primary tumors, ascites and metastases. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr B15.

Abstract A28: Analyses of FOXM1 isoforms in ovarian cancer

Introduction & Objectives: Epithelial ovarian cancer (OC) is the most lethal gynaecological malignancy and the fifth leading cause of cancer death in women in the Western world. Forkhead box M1 (FOXM1) transcription factor was already been described to be overexpressed in various malignancies, playing a key role in cell-cycle progression, chromosomal segregation and genomic stability, and oxidative stress. Moreover, it can also promote drug resistance to herceptin, paclitaxel and cisplatin in breast cancer cells. A recent report from our group has shown, for the first time, that FOXM1 is also overexpressed in OC, being associated with tumor grade. This result seem to indicate an interesting role of this molecule in the progression and resistance to therapy in OC. Our aim is to characterize FOXM1 isoforms in OC through the use of human tissue samples.

Material & Methods: Fresh ovarian primary tumors, ascites and peritoneal metastases from patients suffering advanced serous OC were collected from surgery room and processed for microarray analysis to detect FOXM1 expression levels. FOXM1 isoforms were analysed at mRNA expression level by using RTqPCR in a set of new frozen tissue samples.

Results: We found that FOXM1 overexpression is increased in OC peritoneal metastases. Now, we are characterizing the isoforms of FOXM1 in primary, ascites and metastatic tumors. Nevertheless, more samples need to be analysed in order to have conclusive results.

Conclusions: The present study highlights the role of FOXM1 isoforms in OC dissemination and pursues the idea to elucidate the biologic role of FOXM1 in OC tumorigenesis.

Citation Format: Tatiana Altadill, Marina Rigau, Blanca Majem, Lucia Lanau, Josep Castellví, Ángel García, Assumpció Pérez-Benavente, José Luis Sánchez, Silvia Cabrera, Jordi Xercavins, Josep Maria del Campo, Antonio Gil-Moreno, Marta Llauradó, Jaume Reventós. Analyses of FOXM1 isoforms in ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr A28.

Abstract A56: Identification of a micro RNA profile to predict response to therapy and improve patient survival in ovarian cancer

Introduction & Objectives: Ovarian cancer (OC) is the leading cause of death among gynecological malignancies in developed countries. The standard treatment is surgery plus platinum-paclitaxel (CP/TX) chemotherapy. Nevertheless, 70% of these patients are diagnosed in advanced stages, and, among those, 75% will recur, become resistant to therapies and die. We believe that an improvement in OC survival might be related with an early identification of those patients, since long survival (SV) is related to chemosensitivity. Our aim is to identify an expression profile of micro RNAs (miRNAs) associated with SV of patients with advanced OC.

Material & Methods: Formalin-fixed paraffin-embedded (FFPE) primary tumor tissues from late stage (III/IV) OC patients were collected at the time of surgery for the study. All patients were treated with optimal surgery and standard chemotherapy (CP/TX; after surgery). Samples were divided into two groups; (a) patients with “long SV” (SV>10 years after diagnosis) and (b) patients with “short SV”. The identification of miRNAs associated with each profile of SV was performed using TaqMan Array MicroRNA microfluidic cards in 30 patients.

Results: The identification phase has shown that the majority of the miRNAs appeared to be down-regulated in the group of “short SV” versus the “long SV”. A validation phase in a new group of tumor tissue samples is ready to validate the promising miRNA candidates that seem to be associated with the resistant (short SV) and the sensitive (long SV) profiles.

Conclusions: The ability to identify markers associated with “long SV” in patients with advanced OC could allow transforming the impact of the disease through the reduction of chemotherapy treatments and the reduction of unnecessary health care costs. Moreover, it could permit the generation of knowledge applicable to the future development of new therapies for the “short SV” since they are supposed to be resistant to the therapy.

Citation Format: Marina Rigau, Blanca Majem, Tatiana Altadill, Lucia Lanau, José-Luis Sánchez-Iglesias, Josep Castellví, Assumpció Pérez-Benavente, Silvia Cabrera, Angel García, Jordi Xercavins, Francesc Alameda, Xavier Matias-Guiu, Antonio Gil-Moreno, Josep-Maria Del Campo, Marta Llauradó, Jaume Reventós. Identification of a micro RNA profile to predict response to therapy and improve patient survival in ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr A56.

The present and future of prostate cancer urine biomarkers

In order to successfully cure patients with prostate cancer (PCa), it is important to detect the disease at an early stage. The existing clinical biomarkers for PCa are not ideal, since they cannot specifically differentiate between those patients who should be treated immediately and those who should avoid over-treatment. Current screening techniques lack specificity, and a decisive diagnosis of PCa is based on prostate biopsy. Although PCa screening is widely utilized nowadays, two thirds of the biopsies performed are still unnecessary. Thus the discovery of non-invasive PCa biomarkers remains urgent. In recent years, the utilization of urine has emerged as an attractive option for the non-invasive detection of PCa. Moreover, a great improvement in high-throughput “omic” techniques has presented considerable opportunities for the identification of new biomarkers. Herein, we will review the most significant urine biomarkers described in recent years, as well as some future prospects in that field.

[Molecular biology of bone metastases]

Bone metastases are a frequent and devastating complication in cancer patients. Recently, significant advances in our understanding of the molecular mechanisms responsible for both osteolytic and osteoblastic bone metastases have occurred. The use of OMICS and the availability of appropriate preclinical animal models of bone metastasis have permitted the identification of factors produced by the tumor or by the host stroma in response to the tumor. These types of studies should result in a decrease of the serious skeletal morbidities associated with metastatic prostate cancer and may in the future improve overall survival. In this review the next generation of molecular targets in bone metastasis will be summarized.

Molecular bases of endometrial cancer: new roles for new actors in the diagnosis and the therapy of the disease

Endometrial carcinoma (EC) is the most commonly diagnosed gynecologic malignancy in the western world. The majority of these cancers are curable, but a subset about 15-20% of endometrial tumors exhibits an aggressive phenotype. Based on clinic-pathological and molecular characteristics, EC has been classified into two groups: Type I estrogen-dependent adenocarcinomas, which have a good prognosis and an endometrioid histology, and Type II or non-estrogen-dependent EC associated with poor prognosis and non-endometrioid histology. EC develops as a result of a stepwise accumulation of alterations that seem to be specific of each histological type. However, more knowledge is needed to better understand the differences in the biology and the clinical outcome of EC. We would like to highlight the need to explore new potential biomarkers of EC as a tool for the detection and monitoring of aggressive endometrial tumors that, at the same time, will allow us to develop novel and more selective molecular targeted therapies against EC.

Abstract A32: A urinary mRNA profile to increase the specificity of PSA and reduce the number of unnecessary biopsies

Background: Several studies have demonstrated the usefulness of monitoring an RNA transcript, such as PCA3, in post-prostate massage (PM) urine for increasing the specificity of prostate-specific antigen (PSA) in the detection of prostate cancer (PCa). However, a single marker may not necessarily reflect the multifactorial nature of PCa.

Methods: We analyzed post-PM urine samples from 154 consecutive patients, who presented for prostate biopsies because of elevated serum PSA (>4 ng/ml) and/or abnormal digital rectal exam. We tested whether the putative PCa biomarkers PSMA, PSGR, and PCA3 could be detected by quantitative real-time PCR in post-PM urine sediment. We combined these findings with PSAD to test if a combination of these biomarkers could improve the specificity of actual diagnosis. Afterwards, we specifically tested our model for clinical usefulness in the PSA diagnostic “gray zone” (4–10 ng/ml) on a target subset of 82 men with no prior biopsy.

Results: By univariate analysis, we found that the PSMA, PSGR, PCA3 and PSAD scores were significant predictors of PCa. Using a multiplex model, the area under the multireceiver operating characteristic curve was 0.80 versus 0.89 in the diagnostic gray zone. Fixing the sensitivity at 96%, we obtained a specificity of 40% and 62% in the gray zone. By this approach it would be possible to save approximately 35% of unnecessary biopsies with a sensitivity of 95%.

Conclusions: Taken together, these results provide a strategy for the development of a more accurate model for PCa diagnosis. In the future, a multiplexed, urine-based diagnostic test for PCa with a higher specificity, but the same sensitivity as the serum-PSA test, could be used to determine better which patients should undergo biopsy.

Citation Format: Marina Rigau, Tatiana Altadill, Andreas Doll, Tamara Sequeiros, Mireia Olivan, Marta Garcia, Alex Sanchez, Melania Montes, Israel Ortega, Juan Morote, Jaume Reventos. A urinary mRNA profile to increase the specificity of PSA and reduce the number of unnecessary biopsies [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr A32.

A three-gene panel on urine increases PSA specificity in the detection of prostate cancer

BACKGROUND

Several studies have demonstrated the usefulness of monitoring an RNA transcript, such as PCA3, in post-prostate massage (PM) urine for increasing the specificity of prostate-specific antigen (PSA) in the detection of prostate cancer (PCa). However, a single marker may not necessarily reflect the multifactorial nature of PCa.

METHODS

We analyzed post-PM urine samples from 154 consecutive patients, who presented for prostate biopsies because of elevated serum PSA (>4 ng/ml) and/or abnormal digital rectal exam. We tested whether the putative PCa biomarkers PSMA, PSGR, and PCA3 could be detected by quantitative real-time PCR in post-PM urine sediment. We combined these findings to test if a combination of these biomarkers could improve the specificity of actual diagnosis. Afterwards, we specifically tested our model for clinical usefulness in the PSA diagnostic "gray zone" (4-10 ng/ml) on a target subset of 82 men with no prior biopsy.

RESULTS

By univariate analysis, we found that the PSMA, PSGR, and PCA3 scores were significant predictors of PCa. Using a multiplex model, the area under the multi receiver-operating characteristic curve was 0.74 versus 0.82 in the diagnostic "gray zone." Fixing the sensitivity at 96%, we obtained a specificity of 34% and 50% in the gray zone.

CONCLUSIONS

Taken together, these results provide a strategy for the development of a more accurate model for PCa diagnosis. In the future, a multiplexed, urine-based diagnostic test for PCa with a higher specificity, but the same sensitivity as the serum-PSA test, could be used to determine better which patients should undergo biopsy.

PSGR and PCA3 as biomarkers for the detection of prostate cancer in urine

BACKGROUND

Several studies have demonstrated the usefulness of monitoring an RNA transcript in urine, such as PCA3, for prostate cancer (PCa) diagnosis. PCa screening would benefit from additional biomarkers of higher specificity and could be used in conjunction with prostate-specific antigen (PSA) testing, in order to better determine biopsy candidates.

METHODS

We used urine sediments after prostate massage (PM) from 215 consecutive patients, who presented for prostate biopsy. We tested whether prostate-specific G-protein coupled receptor (PSGR), a biomarker previously described to be over-expressed in PCa tissue, could also be detected by quantitative real-time PCR in post-PM urine sediment. We combined these findings with prostate cancer gene 3 (PCA3), the current gold standard for PCa diagnosis in urine, to test if a combination of both biomarkers could improve the sensitivity of PCA3 alone.

RESULTS

By univariate analysis we found that PSGR and PCA3 were significant predictors of PCa. Receiver operator characteristic curve analysis and its multivariate extension, multivariate ROC (MultiROC), were used to assess the outcome predictive values of the individual and the paired biomarkers. We obtained the following area under the curve values: PSA (0.602), PSGR (0.681), PCA3 (0.656), and PSGRvPCA3 (0.729). Then, we tested whether a combination of PSGR and PCA3 could improve specificity by fixing the sensitivity at 95%. We obtained specificities of 15% (PSGR), 17% (PCA3), and 34% (PSGRvPCA3).

CONCLUSIONS

A multiplexed model including PSGR and PCA3 improves the specificity for the detection of PCa, especially in the area of high sensitivity. This could be clinically useful for determining which patients should undergo biopsy.

A transcriptional signature associated with the onset of benign prostate hyperplasia in a canine model

BACKGROUND

Benign prostatic hyperplasia (BPH) represents the most frequent proliferative abnormality of the human prostate. In spite of the well-characterized architectural development of BPH, little is known about the cellular and molecular events that contribute to it.

METHODS

We have developed an animal model to evaluate the follow-up of hormone-induced BPH and the analysis of the gene expression associated with BPH. Immunohistochemistry on human patient samples validated the BPH-related molecular alterations.

RESULTS

Canine specific Affymetrix microarray analysis performed on sequential biopsies obtained from a beagle dog dynamic model characterized a number of genes altered during the onset of BPH. In addition to the genes involved in calcification, matrix remodeling, detoxification, cell movement, and mucosa protection (MGP, MMP2, TIMP2, ITIH3, GST, MT2A, SULT1A1, FKBP1B, MUC1, STRBP, TFF3), the up-regulation of TGFB3 and CLU indicated a complete adjustment of the transdifferentiation, senescence and apoptosis programs. The up-regulation of Clusterin was validated by RT-qPCR and immunohistochemistry, both in the dog dynamic model and in human samples, further confirming the suitability of the animal model for the study of the molecular alterations associated with BPH.

CONCLUSIONS

Transcriptome analysis performed on a dynamic animal model that accurately mimicked the human clinic, allowed us to characterize a gene expression pattern associated with the onset of BPH.

An orthotopic endometrial cancer mouse model demonstrates a role for RUNX1 in distant metastasis

Endometrial carcinoma is the most common malignancy of the female genital tract in industrialized countries. Metastasis is the major cause of endometrial cancer deaths. Therefore, there is a vital need for clinically relevant in vivo models allowing the elucidation of the molecular and cellular mechanisms underlying metastatic behavior. In this study, we describe an innovative experimental orthotopic model of human endometrial carcinoma. Implantation in the bifurcation of the uterine horns resulted in tumors integrated into the myometrial compartment, which can be used and further exploited for the study of in vivo angiogenesis, myometrial invasion, and the metastatic capacity of endometrial cancer cells. This orthotopic model also represents a suitable tool to analyze how tumorigenesis and distant metastasis of endometrial cancer might be influenced by gene alteration, by modulating its expression in the original cancer cell line. One of the candidate genes implicated in endometrial cancer is the transcription factor RUNX1. The over-expression of RUNX1 in the endometrial cancer cell line HEC1A and the transplantation of these cells to the uterus of nude mice were associated specifically with distant metastasis in the lung. RUNX1 plays a role in the establishment of metastases in endometrial cancer. Translated to the clinics, these models would be equivalent to an advanced undifferentiated carcinoma with node affectation (stage IIIC) and distant metastasis (stage IVB). These patients would be candidates for adjuvant therapy, not efficient until today, and therefore, our models are actually suitable for the design and evaluation of experimental therapies.

Novel molecular profiles of endometrial cancer-new light through old windows

Endometrial carcinoma (EC) is the most common gynecological malignancy in the western world. A widely accepted dualistic model, which has been established on a morphological basis, differentiates EC into two broad categories: Type I oestrogen-dependent adenocarcinoma with an endometrioid morphology and Type II non-oestrogen-dependent EC with a serous papillary or clear cell morphology. Molecular genetic evidence indicates that endometrial carcinoma, as described in other malignancies, likely develops as the result of a stepwise accumulation of alterations in cellular regulatory pathways, such as oncogene activation and tumor suppressor gene inactivation, which lead to dysfunctional cell growth. These molecular alterations appear to be specific in Type I and Type II cancers. In type I endometrioid endometrial cancer, PTEN gene silencing in conjunction with defects in DNA mismatch repair genes, as evidenced by the microsatellite instability phenotype, or mutations in the K-ras and/or beta-catenin genes, are recognized major alterations, which define the progression of the normal endometrium to hyperplasia, to endometrial intraepithelial neoplasia, and then on to carcinoma. In contrast, Type II cancers show mutations of TP53 and Her-2/neu and seem to arise from a background of atrophic endometrium. Nevertheless, despite the great effort made to establish a molecularly-based histological classification, the following issues must still be clarified: what triggers the tumor cells to invade the myometrium and what causes vascular or lymphatic dissemination, finally culminating in metastasis? RUNX1, a transcription factor, was recently identified as one of the most highly over-expressed genes in a microarray study of invasive endometrial carcinoma. Another candidate gene, which may be associated with an initial switch to myometrial infiltration, is the transcription factor ETV5/ERM. These studies, as well as those conducted for other genes possibly involved in the mitotic checkpoint as a major mechanism of carcinogenesis in non-endometrioid endometrial cancer, could help in understanding the differences in the biology and the clinical outcome among histological types.

ERM/ETV5 up-regulation plays a role during myometrial infiltration through matrix metalloproteinase-2 activation in endometrial cancer

We have described recently the Ets family transcription factor, ERM/ETV5, specifically up-regulated in endometrioid endometrial carcinoma (EEC) and associated with myometrial infiltration. Ets family members have been correlated to tumor progression by up-regulating the expression of matrix-degrading proteases. In the present study, we investigated the possibility that in EEC, ERM/ETV5 may act by inducing the expression of genes involved in extracellular matrix remodeling. Unraveling the molecular events associated with the initiation of tumor invasion would represent an obvious improvement for EEC patients. The overexpression of ERM/ETV5 induced scattering in the endometrial cancer cell line Hec-1A, correlating to increased matrix metalloproteinase-2 (MMP-2) gelatinase activity. Both chromatin immunoprecipitation and reversion experiments with RNA interference and specific MMP-2 inhibitor showed a functional link between ERM/ETV5 overexpression and MMP-2 activation. The increased MMP-2 activity associated with overexpressed ERM/ETV5 in a mouse model conferred invasive capacity to endometrial tumors. Orthotopically implanted overexpressing ERM/ETV5 tumors presented a more aggressive and infiltrative pattern of myometrial invasion. Finally, the specific localization of ERM/ETV5 and MMP-2 at the invasive front of myometrial infiltrating human endometrial carcinomas further reinforced the hypothesis of a role for ERM/ETV5 in the early steps of endometrial dissemination. Taken together, these results lead us to propose that in EEC, ERM/ETV5 acts through MMP-2 gelatinolytic activity to confer invasive capabilities, associated with an initial switch to myometrial infiltration. They also postulate ERM/ETV5 as a valuable marker for patient stratification and a transcription pathway that should be evaluated for therapies specifically targeting the initial steps of EEC dissemination.

Molecular determinants of invasion in endometrial cancer

Endometrial carcinoma is the most common gynaecological malignancy in the western world and the most frequent among infiltrating tumours of the female genital tract. Despite the characterisation of molecular events associated with the development of endometrial carcinoma, those associated with the early steps of infiltration and invasion in endometrial cancer are less known. Deep myometrial invasion correlates with more undifferentiated tumours, lymph-vascular invasion, node affectation and decreased global survival. In this review we present an overview of the molecular pathology of myometrial infiltration that defines the initial steps of invasion in endometrial cancer. Down-regulation of E-cadherin as a main player of epithelial to mesenchymal transition, as well as modifications on other molecules involved in cell-cell contacts, render cells with a migratory phenotype. In addition, altered signalling pathways and transcription factors associate with myometrial invasion, histologic grade and metastasis.