The Pancreatic Cancer Early Detection (PRECEDE) Study is a Global Effort to Drive Early Detection: Baseline Imaging Findings in High-Risk Individuals

BACKGROUND

Pancreatic adenocarcinoma (PC) is a highly lethal malignancy with a survival rate of only 12%. Surveillance is recommended for high-risk individuals (HRIs), but it is not widely adopted. To address this unmet clinical need and drive early diagnosis research, we established the Pancreatic Cancer Early Detection (PRECEDE) Consortium.

METHODS

PRECEDE is a multi-institutional international collaboration that has undertaken an observational prospective cohort study. Individuals (aged 18-90 years) are enrolled into 1 of 7 cohorts based on family history and pathogenic germline variant (PGV) status. From April 1, 2020, to November 21, 2022, a total of 3,402 participants were enrolled in 1 of 7 study cohorts, with 1,759 (51.7%) meeting criteria for the highest-risk cohort (Cohort 1). Cohort 1 HRIs underwent germline testing and pancreas imaging by MRI/MR-cholangiopancreatography or endoscopic ultrasound.

RESULTS

A total of 1,400 participants in Cohort 1 (79.6%) had completed baseline imaging and were subclassified into 3 groups based on familial PC (FPC; n=670), a PGV and FPC (PGV+/FPC+; n=115), and a PGV with a pedigree that does not meet FPC criteria (PGV+/FPC-; n=615). One HRI was diagnosed with stage IIB PC on study entry, and 35.1% of HRIs harbored pancreatic cysts. Increasing age (odds ratio, 1.05; P<.001) and FPC group assignment (odds ratio, 1.57; P<.001; relative to PGV+/FPC-) were independent predictors of harboring a pancreatic cyst.

CONCLUSIONS

PRECEDE provides infrastructure support to increase access to clinical surveillance for HRIs worldwide, while aiming to drive early PC detection advancements through longitudinal standardized clinical data, imaging, and biospecimen captures. Increased cyst prevalence in HRIs with FPC suggests that FPC may infer distinct biological processes. To enable the development of PC surveillance approaches better tailored to risk category, we recommend adoption of subclassification of HRIs into FPC, PGV+/FPC+, and PGV+/FPC- risk groups by surveillance protocols.

Nanomedicine and epigenetics: New alliances to increase the odds in pancreatic cancer survival

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers worldwide, primarily due to its robust desmoplastic stroma and immunosuppressive tumor microenvironment (TME), which facilitate tumor progression and metastasis. In addition, fibrous tissue leads to sparse vasculature, high interstitial fluid pressure, and hypoxia, thereby hindering effective systemic drug delivery and immune cell infiltration. Thus, remodeling the TME to enhance tumor perfusion, increase drug retention, and reverse immunosuppression has become a key therapeutic strategy. In recent years, targeting epigenetic pathways has emerged as a promising approach to overcome tumor immunosuppression and cancer progression. Moreover, the progress in nanotechnology has provided new opportunities for enhancing the efficacy of conventional and epigenetic drugs. Nano-based drug delivery systems (NDDSs) offer several advantages, including improved drug pharmacokinetics, enhanced tumor penetration, and reduced systemic toxicity. Smart NDDSs enable precise targeting of stromal components and augment the effectiveness of immunotherapy through multiple drug delivery options. This review offers an overview of the latest nano-based approaches developed to achieve superior therapeutic efficacy and overcome drug resistance. We specifically focus on the TME and epigenetic-targeted therapies in the context of PDAC, discussing the advantages and limitations of current strategies while highlighting promising new developments. By emphasizing the immense potential of NDDSs in improving therapeutic outcomes in PDAC, our review paves the way for future research in this rapidly evolving field.

Selection and Optimization of a Bioink Based on PANC-1- Plasma/Alginate/Methylcellulose for Pancreatic Tumour Modelling

3D bioprinting involves using bioinks that combine biological and synthetic materials. The selection of the most appropriate cell-material combination for a specific application is complex, and there is a lack of consensus on the optimal conditions required. Plasma-loaded alginate and alginate/methylcellulose (Alg/MC) inks were chosen to study their viscoelastic behaviour, degree of recovery, gelation kinetics, and cell survival after printing. Selected inks showed a shear thinning behavior from shear rates as low as 0.2 s-1, and the ink composed of 3% w/v SA and 9% w/v MC was the only one showing a successful stacking and 96% recovery capacity. A 0.5 × 106 PANC-1 cell-laden bioink was extruded with an Inkredible 3D printer (Cellink) through a D = 410 μm tip conical nozzle into 6-well culture plates. Cylindrical constructs were printed and crosslinked with CaCl2. Bioinks suffered a 1.845 Pa maximum pressure at the tip that was not deleterious for cellular viability. Cell aggregates can be appreciated for the cut total length observed in confocal microscopy, indicating a good proliferation rate at different heights of the construct, and suggesting the viability of the selected bioink PANC-1/P-Alg3/MC9 for building up three-dimensional bioprinted pancreatic tumor constructs.

Establishment of Pancreatic Cancer-Derived Tumor Organoids and Fibroblasts From Fresh Tissue

Tumor organoids are three-dimensional (3D) ex vivo tumor models that recapitulate the biological key features of the original primary tumor tissues. Patient-derived tumor organoids have been used in translational cancer research and can be applied to assess treatment sensitivity and resistance, cell-cell interactions, and tumor cell interactions with the tumor microenvironment. Tumor organoids are complex culture systems that require advanced cell culture techniques and culture media with specific growth factor cocktails and a biological basement membrane that mimics the extracellular environment. The ability to establish primary tumor cultures highly depends on the tissue of origin, the cellularity, and the clinical features of the tumor, such as the tumor grade. Furthermore, tissue sample collection, material quality and quantity, as well as correct biobanking and storage are crucial elements of this procedure. The technical capabilities of the laboratory are also crucial factors to consider. Here, we report a validated SOP/protocol that is technically and economically feasible for the culture of ex vivo tumor organoids from fresh tissue samples of pancreatic adenocarcinoma origin, either from fresh primary resected patient donor tissue or patient-derived xenografts (PDX). The technique described herein can be performed in laboratories with basic tissue culture and mouse facilities and is tailored for wide application in the translational oncology field.

Liquid Biopsy in Gastrointestinal Cancers: How Close Are We to Reaching the Clinic?

Gastrointestinal (GI) cancers are malignancies that develop within the digestive system and account for one in four cancer cases according to WHO data [...].

Macrophages direct cancer cells through a LOXL2-mediated metastatic cascade in pancreatic ductal adenocarcinoma

OBJECTIVE

The lysyl oxidase-like protein 2 (LOXL2) contributes to tumour progression and metastasis in different tumour entities, but its role in pancreatic ductal adenocarcinoma (PDAC) has not been evaluated in immunocompetent in vivo PDAC models.

DESIGN

Towards this end, we used PDAC patient data sets, patient-derived xenograft in vivo and in vitro models, and four conditional genetically-engineered mouse models (GEMMS) to dissect the role of LOXL2 in PDAC. For GEMM-based studies, K-Ras +/LSL-G12D;Trp53 LSL-R172H;Pdx1-Cre mice (KPC) and the K-Ras +/LSL-G12D;Pdx1-Cre mice (KC) were crossed with Loxl2 allele floxed mice (Loxl2Exon2 fl/fl) or conditional Loxl2 overexpressing mice (R26Loxl2 KI/KI) to generate KPCL2KO or KCL2KO and KPCL2KI or KCL2KI mice, which were used to study overall survival; tumour incidence, burden and differentiation; metastases; epithelial to mesenchymal transition (EMT); stemness and extracellular collagen matrix (ECM) organisation.

RESULTS

Using these PDAC mouse models, we show that while Loxl2 ablation had little effect on primary tumour development and growth, its loss significantly decreased metastasis and increased overall survival. We attribute this effect to non-cell autonomous factors, primarily ECM remodelling. Loxl2 overexpression, on the other hand, promoted primary and metastatic tumour growth and decreased overall survival, which could be linked to increased EMT and stemness. We also identified tumour-associated macrophage-secreted oncostatin M (OSM) as an inducer of LOXL2 expression, and show that targeting macrophages in vivo affects Osm and Loxl2 expression and collagen fibre alignment.

CONCLUSION

Taken together, our findings establish novel pathophysiological roles and functions for LOXL2 in PDAC, which could be potentially exploited to treat metastatic disease.

Low-intensity continuous ultrasound to inhibit cancer cell migration

In recent years, it has been verified that collective cell migration is a fundamental step in tumor spreading and metastatic processes. In this paper, we demonstrate for the first time how low-intensity ultrasound produces long-term inhibition of collective migration of epithelial cancer cells in wound healing processes. In particular, we show how pancreatic tumor cells, PANC-1, grown as monolayers in vitro respond to these waves at frequencies close to 1 MHz and low intensities (<100 mW cm^-2) for 48-72 h of culture after some minutes of a single ultrasound irradiation. This new strategy opens a new line of action to block the spread of malignant cells in cancer processes. Despite relevant spatial variations of the acoustic pressure amplitude induced in the assay, the cells behave as a whole, showing a collective dynamic response to acoustic performance. Experiments carried out with samples without previous starving showed remarkable effects of the LICUs from the first hours of culture, more prominent than those with experiments with monolayers subjected to fasting prior to the experiments. This new strategy to control cell migration demonstrating the effectiveness of LICUS on not starved cells opens a new line of action to study effects of in vivo ultrasonic actuation on tumor tissues with malignant cells. This is a proof-of-concept study to demonstrate the physical effects of ultrasound stimulation on tumor cell migration. An in-depth biological study of the effects of ultrasounds and underlying biological mechanisms is on-going but out of the scope of this article.

The PRECEDE consortium: A longitudinal international cohort study of individuals with genetic risk or familial pancreatic cancer

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Background: Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease with lack of effective early detection strategies. There is an incomplete understanding of who is at risk for PDAC development and the contribution of heritability to that risk. Further, efforts at biomarker development for detection of early stage disease have been hampered by small sample sizes, lack of coordination, and inadequate access to high quality clinical data and biospecimens in relevant clinical populations. The PRECEDE Consortium was established to serve as a collaborative international network of PDAC clinical and research centers to accelerate early detection advances by standardizing collection of clinical data and biospecimens from patients at increased risk for PDAC. The consortium goal is to increase the overall survival rate for PDAC to 50% in 10 years by enabling transformative biomarker-driven discoveries in early detection of high-risk premalignant lesions and early stage cancers. Methods: The PRECEDE Consortium (NCT04970056; precedestudy.org) launched in 2019 and began enrollment in May, 2020. Data and biospecimen sharing are required for centers to join the consortium, which is facilitated through use of standardized data and biospecimen collection, and a centralized database (PRECEDELink) managed by a data coordinating center (Arbor Research). Imaging and clinical sequencing data will be stored and analyzed via a PRECEDE solution in the Amazon Web Services cloud. Participants age 18-90 are enrolled into one of seven cohorts based on personal and/or family history of PDAC and carrier status of pathogenic germline variants (PGV) in cancer predisposition genes (CPG). Three-generation pedigrees are collected at enrolment from participants, and standardized clinical germline testing is offered. Blood sample collection for DNA, plasma, and serum is completed at enrollment, and repeated annually for individuals meeting guidelines for annual surveillance. Results: To date, 24 clinical sites have enrolled 2187 participants, with a target of 10,000 participants enrolled from100 sites over the next 5 years. Among enrolled patients, 55% meet criteria for annual surveillance by MRI or endoscopic ultrasound. Demographics of the cohort to date: 56% female; 73% white; 35% CPG PGV carriers; 32% meet criteria for familial pancreatic cancer. Conclusions: The PRECEDE Consortium study is a large international, longitudinal, prospective cohort study designed to accelerate the pace and scale of early diagnosis. Planned projects will address modifiers of risk, penetrance of disease, creating comprehensive risk models for clinical decision-making, and development and validation of biomarker assays. The PRECEDE Consortium provides a unique, innovative platform to bring together key stakeholders (academia, patients, public and private sector) to effect progress.

Timeline of Development of Pancreatic Cancer and Implications for Successful Early Detection in High-Risk Individuals

BACKGROUND & AIMS

To successfully implement imaging-based pancreatic cancer (PC) surveillance, understanding the timeline and morphologic features of neoplastic progression is key. We aimed to investigate the progression to neoplasia from serial prediagnostic pancreatic imaging tests in high-risk individuals and identify factors associated with successful early detection.

METHODS

We retrospectively examined the development of pancreatic abnormalities in high-risk individuals who were diagnosed with PC or underwent pancreatic surgery, or both, in 16 international surveillance programs.

RESULTS

Of 2552 high-risk individuals under surveillance, 28 (1%) developed neoplastic progression to PC or high-grade dysplasia during a median follow-up of 29 months after baseline (interquartile range [IQR], 40 months). Of these, 13 of 28 (46%) presented with a new lesion (median size, 15 mm; range 7-57 mm), a median of 11 months (IQR, 8; range 3-17 months) after a prior examination, by which time 10 of 13 (77%) had progressed beyond the pancreas. The remaining 15 of 28 (54%) had neoplastic progression in a previously detected lesion (12 originally cystic, 2 indeterminate, 1 solid), and 11 (73%) had PC progressed beyond the pancreas. The 12 patients with cysts had been monitored for 21 months (IQR, 15 months) and had a median growth of 5 mm/y (IQR, 8 mm/y). Successful early detection (as high-grade dysplasia or PC confined to the pancreas) was associated with resection of cystic lesions (vs solid or indeterminate lesions (odds ratio, 5.388; 95% confidence interval, 1.525-19.029) and small lesions (odds ratio, 0.890/mm; 95% confidence interval 0.812-0.976/mm).

CONCLUSIONS

In nearly half of high-risk individuals developing high-grade dysplasia or PC, no prior lesions are detected by imaging, yet they present at an advanced stage. Progression can occur before the next scheduled annual examination. More sensitive diagnostic tools or a different management strategy for rapidly growing cysts are needed.

Ultrasounds in cancer therapy: A summary of their use and unexplored potential

Ultrasounds (US) are a non-ionizing mechanical wave, with less adverse effects than conventional pharmacological or surgical treatments. Different biological effects are induced in tissues and cells by ultrasound actuation depending on acoustic parameters, such as the wave intensity, frequency and treatment dose. This non-ionizing radiation has considerable applications in biomedicine including surgery, medical imaging, physical therapy and cancer therapy. Depending on the wave intensity, US are applied as high-intensity ultrasounds (HIUS) and low-intensity pulsed ultrasounds (LIPUS), with different effects on cells and tissues. HIUS produce thermal and mechanical effects, resulting in a large localized temperature increase, leading to tissue ablation and even tumor necrosis. This can be achieved by focusing low intensity waves emitted from different electrically shifted transducers, known as high-intensity focused ultrasounds (HIFU). LIPUS have been used extensively as a therapeutic, surgical and diagnostic tool, with diverse biological effects observed in tissues and cultured cells. US represent a non-invasive treatment strategy that can be applied to selected areas of the body, with limited adverse effects. In fact, tumor ablation using HIFU has been used as a curative treatment in patients with an early-stage pancreatic tumor and is an effective palliative treatment in patients with advanced stage disease. However, the biological effects, dose standardization, benefit-risk ratio and safety are not fully understood. Thus, it is an emerging field that requires further research in order to reach its full potential.

Detection of Early-Stage Pancreatic Ductal Adenocarcinoma From Blood Samples: Results of a Multiplex Biomarker Signature Validation Study

INTRODUCTION

The IMMray PanCan-d test combines an 8-plex biomarker signature with CA19-9 in a proprietary algorithm to detect pancreatic ductal adenocarcinoma (PDAC) in serum samples. This study aimed to validate the clinical performance of the IMMray PanCan-d test and to better understand test performance in Lewis-null (le/le) individuals who cannot express CA19-9.

METHODS

Serum samples from 586 individuals were analyzed with the IMMray PanCan-d biomarker signature and CA19-9 assay, including 167 PDAC samples, 203 individuals at high risk of familial/hereditary PDAC, and 216 healthy controls. Samples were collected at 11 sites in the United States and Europe. The study was performed by Immunovia, Inc (Marlborough, MA), and sample identity was blinded throughout the study. Test results were automatically generated using validated custom software with a locked algorithm and predefined decision value cutoffs for sample classification.

RESULTS

The IMMray PanCan-d test distinguished PDAC stages I and II (n = 56) vs high-risk individuals with 98% specificity and 85% sensitivity and distinguished PDAC stages I-IV vs high-risk individuals with 98% specificity and 87% sensitivity. We identified samples with a CA19-9 value of 2.5 U/mL or less as probable Lewis-null (le/le) individuals. Excluding these 55 samples from the analysis increased the IMMray PanCan-d test sensitivity to 92% for PDAC stages I-IV (n = 157) vs controls (n = 379) while maintaining specificity at 99%; test sensitivity for PDAC stages I and II increased from 85% to 89%.

DISCUSSION

These results demonstrate the IMMray PanCan-d blood test can detect PDAC with high specificity (99%) and sensitivity (92%).

DNA Methylation Mediates EMT Gene Expression in Human Pancreatic Ductal Adenocarcinoma Cell Lines

Due to abundant stroma and extracellular matrix, accompanied by lack of vascularization, pancreatic ductal adenocarcinoma (PDAC) is characterized by severe hypoxia. Epigenetic regulation is likely one of the mechanisms driving hypoxia-induced epithelial-to-mesenchymal transition (EMT), responsible for PDAC aggressiveness and dismal prognosis. To verify the role of DNA methylation in this process, we assessed gene expression and DNA methylation changes in four PDAC cell lines. BxPC-3, MIA PaCa-2, PANC-1, and SU.86.86 cells were exposed to conditioned media containing cytokines and inflammatory molecules in normoxic and hypoxic (1% O2) conditions for 2 and 6 days. Cancer Inflammation and Immunity Crosstalk and Human Epithelial to Mesenchymal Transition RT² Profiler PCR Arrays were used to identify top deregulated inflammatory and EMT-related genes. Their mRNA expression and DNA methylation were quantified by qRT-PCR and pyrosequencing. BxPC-3 and SU.86.86 cell lines were the most sensitive to hypoxia and inflammation. Although the methylation of gene promoters correlated with gene expression negatively, it was not significantly influenced by experimental conditions. However, DNA methyltransferase inhibitor decitabine efficiently decreased DNA methylation up to 53% and reactivated all silenced genes. These results confirm the role of DNA methylation in EMT-related gene regulation and uncover possible new targets involved in PDAC progression.

Soluble AXL is a novel blood marker for early detection of pancreatic ductal adenocarcinoma and differential diagnosis from chronic pancreatitis

Background

Early diagnosis is crucial for patients with pancreatic ductal adenocarcinoma (PDAC). The AXL receptor tyrosine kinase is proteolytically processed releasing a soluble form (sAXL) into the blood stream. Here we explore the use of sAXL as a biomarker for PDAC.

Methods

AXL was analysed by immunohistochemistry in human pancreatic tissue samples. RNA expression analysis was performed using TCGA/GTEx databases. The plasma concentrations of sAXL, its ligand GAS6, and CA19-9 were studied in two independent cohorts, the HMar cohort (n = 59) and the HClinic cohort (n = 142), including healthy controls, chronic pancreatitis (CP) or PDAC patients, and in a familial PDAC cohort (n = 68). AXL expression and sAXL release were studied in PDAC cell lines and murine models.

Findings

AXL is increased in PDAC and precursor lesions as compared to CP or controls. sAXL determined in plasma from two independent cohorts was significantly increased in the PDAC group as compared to healthy controls or CP patients. Patients with high levels of AXL have a lower overall survival. ROC analysis of the plasma levels of sAXL, GAS6, or CA19-9 in our cohorts revealed that sAXL outperformed CA19-9 for discriminating between CP and PDAC. Using both sAXL and CA19-9 increased the diagnostic value. These results were validated in murine models, showing increased sAXL specifically in animals developing PDAC but not those with precursor lesions or acinar tumours.

Interpretation

sAXL appears as a biomarker for early detection of PDAC and PDAC–CP discrimination that could accelerate treatment and improve its dismal prognosis.

Funding

This work was supported by grants PI20/00625 (PN), RTI2018-095672-B-I00 (AM and PGF), PI20/01696 (MG) and PI18/01034 (AC) from MICINN-FEDER and grant 2017/SGR/225 (PN) from Generalitat de Catalunya.

Doctors' reporting of mental health stigma and barriers to help-seeking

BACKGROUND

Medical practitioners experience high levels of mental disorders but may be reluctant to seek care.

AIMS

To determine medical practitioner attitudes towards other doctors with anxiety/depression, barriers to seeking mental healthcare, treatments received for depression and the effects of age.

METHODS

Data from the National Mental Health Survey of Doctors and Medical Students, conducted in Australia, were analysed (N = 10 038 medical practitioners). Attitudes to anxiety/depression were assessed with 12 statements (total stigma score, range 12-60). Barriers to seeking professional help, and coping strategies used, for anxiety/depression were measured. Practitioners with a history of depression were asked what personal supports and treatments were received. Practitioners were compared by age-younger (40 years and younger), middle-aged (41-60) and older (61+).

RESULTS

Attitudes and help-seeking behaviours varied with age. Older doctors had a more positive outlook and less total stigma, with the exception that they believed a doctor with anxiety/depression was less reliable. Younger practitioners were most likely to report barriers, such as confidentiality, impact on career progression and registration, to seeking help. For practitioners with depression, counselling and counselling plus medication were most likely to be received by the younger and middle-aged groups, whereas medication alone was most likely to be received by the middle-aged and older groups.

CONCLUSIONS

Stigmatizing attitudes towards mental disorder and barriers to help-seeking remain prevalent within the medical profession. Our results suggest doctors' health programs should address mental health stigma in younger practitioners and facilitate education about psychological treatments in older practitioners.

Correction: Earl et al. Somatic Mutation Profiling in the Liquid Biopsy and Clinical Analysis of Hereditary and Familial Pancreatic Cancer Cases Reveals KRAS Negativity and a Longer Overall Survival. Cancers 2021, 13, 1612

The authors wish to make the following corrections to this paper [...].

Biomarkers Associated with Regorafenib First-Line Treatment Benefits in Metastatic Colorectal Cancer Patients: REFRAME Molecular Study

Simple Summary

Biomarkers able to predict response and toxicity upon regorafenib therapy for colorectal cancer (CRC) are critical for treatment choice, particularly relevant in fragile patients. Here, we validated for the first time 18 distinct microRNAs (miRNAs) detected in serum and primary tumor samples, three germline single-nucleotide polymorphisms (SNPs) in vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (VEGFR) genes, and low levels of Notch 1 expression in the primary tumor as predictive biomarkers of different features. Specifically, these markers were associated with a favorable response to treatment, disease stage, and relapse, as well as the appearance of asthenia. Therefore, these markers can be potentially useful biomarkers for patient stratification and for providing a more personalized and effective therapeutic strategy in fragile patients, while limiting the appearance of adverse effects.

Abstract

First-line treatment with regorafenib in frail metastatic colorectal cancer (mCRC) patients has shown some benefit. To accurately identify such patients before treatment, we studied blood biomarkers and primary tumor molecules. We unveiled serum microRNAs (miRNAs), single-nucleotide polymorphisms (SNPs) in angiogenic-related genes, and Notch 1 expression as biomarkers associated with response or toxicity. MicroRNA array profiling and genotyping of selected SNPs were performed in the blood of fragile mCRC patients treated with regorafenib. Notch 1 and CRC-associated miRNA expression was also analyzed in tumors. High levels of miR-185-5p in serum, rs7993418 in the vascular endothelial growth factor receptor 1 (VEGFR1) gene, and Notch 1 expression in biopsies were associated with a favorable response to treatment. Serum levels of miR-126-3p and miR-152-3p and tumor expression of miR-92a-1-5p were associated with treatment toxicity, particularly interesting in patients exhibiting comorbidities, and high levels of miR-362-3p were associated with asthenia. Additionally, several miRNAs were associated with the presence of metastasis, local recurrence, and peritoneal metastasis. Besides, miRNAs determined in primary tumors were associated with tumor-node-metastasis (TNM) staging. The rs2305948 and rs699947 SNPs in VEGFR2 and VEGFA, respectively, were markers of poor prognosis correlating with locoregional relapse, a higher N stage, and metastatic shedding. In conclusion, VEGF and VEGFR SNPs, miRNAs, and Notch 1 levels are potential useful biomarkers for the management of advanced CRC under regorafenib treatment.

Epigenetic Landscape in Pancreatic Ductal Adenocarcinoma: On the Way to Overcoming Drug Resistance?

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive solid malignancies due to the rapid rate of metastasis and high resistance to currently applied cancer therapies. The complex mechanism underlying the development and progression of PDAC includes interactions between genomic, epigenomic, and signaling pathway alterations. In this review, we summarize the current research findings on the deregulation of epigenetic mechanisms in PDAC and the influence of the epigenome on the dynamics of the gene expression changes underlying epithelial–mesenchymal transition (EMT), which is responsible for the invasive phenotype of cancer cells and, therefore, their metastatic potential. More importantly, we provide an overview of the studies that uncover potentially actionable pathways. These studies provide a scientific basis to test epigenetic drug efficacy in synergy with other anticancer therapies in future clinical trials, in order to reverse acquired therapy resistance. Thus, epigenomics has the potential to generate relevant new knowledge of both a biological and clinical impact. Moreover, the potential, hurdles, and challenges of predictive biomarker discoveries will be discussed, with a special focus on the promise of liquid biopsies.

ISG15 and ISGylation is required for pancreatic cancer stem cell mitophagy and metabolic plasticity

Pancreatic cancer stem cells (PaCSCs) drive pancreatic cancer tumorigenesis, chemoresistance and metastasis. While eliminating this subpopulation of cells would theoretically result in tumor eradication, PaCSCs are extremely plastic and can successfully adapt to targeted therapies. In this study, we demonstrate that PaCSCs increase expression of interferon-stimulated gene 15 (ISG15) and protein ISGylation, which are essential for maintaining their metabolic plasticity. CRISPR-mediated ISG15 genomic editing reduces overall ISGylation, impairing PaCSCs self-renewal and their in vivo tumorigenic capacity. At the molecular level, ISG15 loss results in decreased mitochondrial ISGylation concomitant with increased accumulation of dysfunctional mitochondria, reduced oxidative phosphorylation (OXPHOS) and impaired mitophagy. Importantly, disruption in mitochondrial metabolism affects PaCSC metabolic plasticity, making them susceptible to prolonged inhibition with metformin in vivo. Thus, ISGylation is critical for optimal and efficient OXPHOS by ensuring the recycling of dysfunctional mitochondria, and when absent, a dysregulation in mitophagy occurs that negatively impacts PaCSC stemness.

The ubiquitin-like modifier ISG15 exerts post-translational protein regulation through ISGylation. Here, the authors show that ISGylation is necessary for pancreatic cancer stem cell self-renewal and tumourigenesis by supporting the recycling of non-functional mitochondria.

A comprehensive analysis of candidate genes in familial pancreatic cancer families reveals a high frequency of potentially pathogenic germline variants

BACKGROUND

The 5-year survival rate of patients with pancreatic ductal adenocarcinoma (PDAC) is around 5% due to the fact that the majority of patients present with advanced disease that is treatment resistant. Familial pancreatic cancer (FPC) is a rare disorder that is defined as a family with at least two affected first degree relatives, with an estimated incidence of 4%-10%. The genetic basis is unknown in the majority of families although around 10%-13% of families carry germline mutations in known genes associated with hereditary cancer and pancreatitis syndromes.

METHODS

Panel sequencing was performed of 35 genes associated with hereditary cancer in 43 PDAC cases from families with an apparent hereditary pancreatic cancer syndrome.

FINDINGS

Pathogenic variants were identified in 19% (5/26) of PDAC cases from pure FPC families in the genes MLH1, CDKN2A, POLQ and FANCM. Low frequency potentially pathogenic VUS were also identified in 35% (9/26) of PDAC cases from FPC families in the genes FANCC, MLH1, PMS2, CFTR, APC and MUTYH. Furthermore, an important proportion of PDAC cases harboured more than one pathogenic, likely pathogenic or potentially pathogenic VUS, highlighting the multigene phenotype of FPC.

INTERPRETATION

The genetic basis of familial or hereditary pancreatic cancer can be explained in 21% of families by previously described hereditary cancer genes. Low frequency variants in other DNA repair genes are also present in 35% of families which may contribute to the risk of pancreatic cancer development.

FUNDING

This study was funded by the Instituto de Salud Carlos III (Plan Estatal de I + D + i 2013-2016): ISCIII (PI09/02221, PI12/01635, PI15/02101 and PI18/1034) and co-financed by the European Development Regional Fund ''A way to achieve Europe'' (ERDF), the Biomedical Research Network in Cancer: CIBERONC (CB16/12/00446), Red Temática de investigación cooperativa en cáncer: RTICC (RD12/0036/0073) and La Asociación Española contra el Cáncer: AECC (Grupos Coordinados Estables 2016).

Incidental findings in pancreas screening programs for high-risk individuals: Results from three European expert centers

Background

Widespread abdominal imaging has led to a substantial increase in the detection of incidentalomas. Currently, an increasing number of centers offer surveillance of the pancreas to individuals at high risk (IARs) of pancreatic ductal adenocarcinoma (PDAC).

Objective

The aims of this study were to evaluate the frequency and type of incidental findings in a magnetic resonance imaging (MRI)-based surveillance program for IARs for PDAC, and to discuss the benefit of detecting these lesions.

Methods

The outcome of MRI screening was reviewed in 568 individuals from three long-term pancreas surveillance programs conducted at three large European expert centers. All MRIs were studied in detail for the presence of incidental lesions.

Results

The most common lesions were liver cysts, renal cysts and liver hemangioma, which together comprised 75% of all lesions. Only five (0.9%) patients underwent surgery for a benign lesion. Cancer was detected in 11 patients (1.9%); early detection of tumors was beneficial in at least five cases.

Conclusion

The present study demonstrates that extrapancreatic incidentaloma is a common finding in IARs for PDAC, but rarely requires additional treatment. CDKN2A-p16-Leiden mutation carriers were the only patient group found to harbor a substantial number of cancers, and detection resulted in benefit in several cases.

Circulating endothelial cells: Prognostic value in patients with glioblastoma

e13517

Background: Glioblastoma (GB) is an aggressive tumor. Circulating Endothelial Cells (CECs) can be detected in peripheral blood and have been related to angiogenesis. CECs have an unclear prognostic value in patients with glioblastoma. The objective of this study was to quantify the presence and number of CECs in GB patients and determine its potential prognostic role. Methods: In this prospective, single center study, peripheral blood samples were obtained at the time of GB diagnosis. For the detection of CECs, 4 ml of blood was analyzed using the CellSearch system (Veridex). CEC blood samples were classified as CD146+, CD105+, CD45− and DAPI+. CEC detection was performed prior to surgery in a total of 26 patients and 22 patients with glioblastoma were included in the final analysis. We mesured progression free survival (PFS) and overall survival (OS). Results: Between 2014 and 2016, twenty two patients with histologically confirmed glioblastoma were studied. There were 14 males and 8 females with an average age of 63 years (range 42-81). A complete resection was achieved in 50% of cases, partial or subtotal resection in 31.8% and biopsy in 18%. The mean number of CECs was 59.3 cells/mL (range 0-954). Patients were classified into two groups depending on the number of CECs: group 1 had a CEC count below the mean and group 2 had a CEC count above the mean. A total of 17 patients (77.2%) were in group 1 and 5 patients (22.7%) were in group 2.The median OS was 14.4 months (range -0.36-33.36) for the entire study population. The median OS was 17.4 months (IC95% 11.47-23.37) for patients in group 1 and 8.12 months for patients in group 2 (IC 95% 4.38-11.85) p = 0.002. The median PFS was 8.94 m (IC95% 5.1-12.69) for group 1 and 3.95 for group 2 (IC 95% 2.91-4.98) p = 0.097. Conclusions: CECs can be detected in recently diagnosed GB patients. The present study demonstrates a possible prognostic value for CEC determination in GB cases at the time of diagnosis.

Tumor-associated macrophage-secreted 14-3-3ζ signals via AXL to promote pancreatic cancer chemoresistance

Pancreatic ductal adenocarcinoma (PDAC) is an inherently chemoresistant tumor. Chemotherapy leads to apoptosis of cancer cells, and in previous studies we have shown that tumor-associated macrophage (TAM) infiltration increases following chemotherapy in PDAC. Since one of the main functions of macrophages is to eliminate apoptotic cells, we hypothesized that TAMs phagocytose chemotherapy-induced apoptotic cells and secrete factors, which favor PDAC chemoresistance. To test this hypothesis, primary human PDAC cultures were treated with conditioned media (CM) from monocyte-derived macrophage cultures incubated with apoptotic PDAC cells (MØ^ApopCM). MØ^ApopCM pretreatment rendered naïve PDAC cells resistant to Gemcitabine- or Abraxane-induced apoptosis. Proteomic analysis of MØ^ApopCM identified YWHAZ/14-3-3 protein zeta/delta (14-3-3ζ), a major regulator of apoptotic cellular pathways, as a potential mediator of chemoresistance, which was subsequently validated in patient transcriptional datasets, serum samples from PDAC patients and using recombinant 14-3-3ζ and inhibitors thereof. Moreover, in mice bearing orthotopic PDAC tumors, the antitumor potential of Gemcitabine was significantly enhanced by elimination of TAMs using clodronate liposomes or by pharmacological inhibition of the Axl receptor tyrosine kinase, a 14-3-3ζ interacting partner. These data highlight a unique regulatory mechanism by which chemotherapy-induced apoptosis acts as a switch to initiate a protumor/antiapoptotic mechanism in PDAC via 14-3-3ζ/Axl signaling, leading to phosphorylation of Akt and activation of cellular prosurvival mechanisms. The data presented therefore challenge the idea that apoptosis of tumor cells is therapeutically beneficial, at least when immune sensor cells, such as macrophages, are present.

Increased plasma levels of galectin-1 in pancreatic cancer: potential use as biomarker

Pancreatic ductal adenocarcinoma (PDA) is the most frequent type of pancreatic cancer and one of the deadliest diseases overall. New biomarkers are urgently needed to allow early diagnosis, one of the only factors that currently improves prognosis. Here we analyzed whether the detection of circulating galectin-1 (Gal-1), a soluble carbohydrate-binding protein overexpressed in PDA tissue samples, can be used as a biomarker for PDA. Gal-1 levels were determined by ELISA in plasma from healthy controls and patients diagnosed with PDA, using three independent cohorts. Patients with chronic pancreatitis (CP) were also included in the study to analyze the potential of Gal-1 to discriminate between cancer and inflammatory process. Plasma Gal-1 levels were significantly increased in patients with PDA as compared to controls in all three cohorts. Gal-1 sensitivity and specificity values were similar to that of the CA19-9 biomarker (the only FDA-approved blood test biomarker for PDA), and the combination of Gal-1 and CA19-9 significantly improved their individual discriminatory powers. Moreover, high levels of Gal-1 were associated with lower survival in patients with non-resected tumors. Collectively, our data indicate a strong potential of using circulating Gal-1 levels as a biomarker for detection and prognostics of patients with PDA.

Differential distribution and enrichment of non-coding RNAs in exosomes from normal and Cancer-associated fibroblasts in colorectal cancer

Exosome production from cancer-associated fibroblasts seems to be an important driver of tumor progression. We report the first in-depth biotype characterization of ncRNAs, analyzed by Next Generation Sequencing and Bioinformatics, expressed in established primary human normal and cancer-associated fibroblasts (CAFs) from cancer and normal mucosa tissues from 9 colorectal cancer patients, and/or packaged in their derived exosomes. Differential representation and enrichment analyses based on these ncRNAs revealed a significant number of differences between the ncRNA content of exosomes and the expression patterns of the normal and cancer-associated fibroblast cells. ncRNA regulatory elements are specifically packaged in CAF-derived exosomes, supporting a specific cross-talk between CAFs and colon cancer cells and/or other stromal cells, mediated by exosomes. These sncRNAs are potential biomarkers present in cancer-associated fibroblast-derived exosomes, which should thereby contribute to developing new non-invasive diagnostic, prognostic and predictive methods for clinical applications in management of cancer patients.

Refinement of screening for familial pancreatic cancer

OBJECTIVE

Surveillance programmes are recommended for individuals at risk (IAR) of familial pancreatic cancer (FPC) to detect early pancreatic cancer (pancreatic ductal adenocarcinoma, PDAC). However, the age to begin screening and the optimal screening protocol remain to be determined.

METHODS

IAR from non-CDKN2A FPC families underwent annual screening by MRI with endoscopic ultrasonography (EUS) in board-approved prospective screening programmes at three tertiary referral centres. The diagnostic yield according to age and different screening protocols was analysed.

RESULTS

253 IAR with a median age of 48 (25-81) years underwent screening with a median of 3 (1-11) screening visits during a median follow-up of 28 (1-152) months. 134 (53%) IAR revealed pancreatic lesions on imaging, mostly cystic (94%), on baseline or follow-up screening. Lesions were significantly more often identified in IAR above the age of 45 years (p<0.0001). In 21 IAR who underwent surgery, no significant lesions (PDAC, pancreatic intraepithelial neoplasia (PanIN) 3 lesions, high-grade intraductal papillary mucinous neoplasia (IPMN)) were detected before the age of 50 years. Potentially relevant lesions (multifocal PanIN2 lesions, low/moderate-grade branch-duct IPMNs) occurred also significantly more often after the age of 50 years (13 vs 2, p<0.0004). The diagnostic yield of potentially relevant lesions was not different between screening protocols using annual MRI with EUS (n=98) or annual MRI with EUS every 3rd year (n=198) and between IAR screened at intervals of 12 months (n=180) or IAR that decided to be screened at ≥24 months intervals (n=30).

CONCLUSIONS

It appears safe to start screening for PDAC in IAR of non-CDKN2a FPC families at the age of 50 years. MRI-based screening supplemented by EUS at baseline and every 3rd year or when changes in MRI occur appears to be efficient.

Benefit of Surveillance for Pancreatic Cancer in High-Risk Individuals: Outcome of Long-Term Prospective Follow-Up Studies From Three European Expert Centers

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis. Hereditary factors play a role in the development of PDAC in 3% to 5% of all patients. Surveillance of high-risk groups, may facilitate detection of PDAC at an early stage. The aim of this study was to assess whether surveillance aids detection of early-stage PDAC or precursor lesions (PRLs) and improves the prognosis.

PATIENTS AND METHODS

Screening outcomes were collected from three European centers that conduct prospective screening in high-risk groups including families with clustering of PDAC (familial pancreatic cancer [FPC]) or families with a gene defect that predisposes to PDAC. The surveillance program consisted of annual magnetic resonance imaging, magnetic resonance cholangiopancreatography, and/or endoscopic ultrasound.

RESULTS

Four hundred eleven asymptomatic individuals participated in the surveillance programs, including 178 CDKN2A mutation carriers, 214 individuals with FPC, and 19 BRCA1/2 or PALB2 mutation carriers. PDAC was detected in 13 (7.3%) of 178 CDKN2A mutation carriers. The resection rate was 75%, and the 5-year survival rate was 24%. Two CDKN2A mutation carriers (1%) underwent surgical resection for low-risk PRL. Two individuals (0.9%) in the FPC cohort had a pancreatic tumor, including one advanced PDAC and one early grade 2 neuroendocrine tumor. Thirteen individuals with FPC (6.1%) underwent surgical resection for a suspected PRL, but only four (1.9%) had high-risk lesions (ie, high-grade intraductal papillary mucinous neoplasms or grade 3 pancreatic intraepithelial neoplasms). One BRCA2 mutation carrier was found to have PDAC, and another BRCA2 mutation carrier and a PALB2 mutation carrier underwent surgery and were found to have low-risk PRL. No serious complications occurred as consequence of the program.

CONCLUSION

Surveillance of CDNK2A mutation carriers is relatively successful, detecting most PDACs at a resectable stage. The benefit of surveillance in families with FPC is less evident.

Circulating biomarkers exploratory study in loco-regional gastroesophageal adenocarcinoma patients

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Background: Patients diagnosed with gastroesophageal adenocarcinoma (GEA) have a poor prognosis despite curative attempts with multimodal treatment including surgery, chemotherapy (CT) and radiotherapy (RT). VEGF, EpCAM, MUC1, CK19 and CK20 and CD133 have shown to provide additional prognostic information in advanced GEA patients. Methods: Circulating mRNA of total VEGF (and 2 VEGF isoforms 121 and 165), EpCAM, MUC1 and CD133 were determined in 36 loco-regional GEA patients (pts). Blood samples were collected before surgery or, when indicated, before the preoperative chemotherapy treatment, within a 7 days window. Additionally, 14 healthy volunteers and 7 advanced GEA pts were included to comparative analyses. The Wilcoxon test was used to assess differences in expression among the groups. Results: Pre-surgery CT was administered in 30 pts (79%). ECF or its modifications were administered in 22 pts, and FOLFOX in 7 pts. Type of resection achieved was R0 (19 pts, 59%), R1(7 pts, 22%) and R2 (6 pts, 10%). Post-surgery CT was administered in 22 pts (73%) including ECF or its modifications (10 pts), FOLFOX (7 pts) and CT-RT (4 pts). PFS occurred in 19 pts (61%) and 34 patients remained alive at the time of this analysis. Patients diagnosed with loco-regional GEA exhibited over expression as compared to healthy volunteers of VEGFi121 in 17 pts (47%) by 33-fold median change (IQR 5-43, %, p = 0.0008); VEGFi165 in 17 pts (47%) by 15-fold (IQR 5-36, p = 0.002); total VEGF in 19 pts (53%) by 15 fold (IQR 8-59, p = 0.01); EpCAM in 8 pts (22%) by 3-fold (IQR 0.5-3, NS); MUC1 in 19 pts (53%) by 23-fold (IQR7-59, p = 0.0008); and CD133 in 2 pts (6%) by 55-fold (IQR 28-83, NS). CK20 expression was not detected in healthy controls but was detected in 3 patients. Conclusions: VEGF and its isoforms VEGF121 and VEGF165 and MUC1 are potential diagnostic biomarkers in GEA. Due to the short follow-up of patients we cannot yet evaluate their role as prognostic biomarkers.

Circulating tumor cells (Ctc) and kras mutant circulating free Dna (cfdna) detection in peripheral blood as biomarkers in patients diagnosed with exocrine pancreatic cancer

BACKGROUND

Pancreatic cancer remains one of the most difficult cancers to treat with the poorest prognosis. The key to improving survival rates in this disease is early detection and monitoring of disseminated and residual disease. However, this is hindered due to lack reliable diagnostic and predictive markers which mean that the majority of patients succumb to their condition within a few months.

METHODS

We present a pilot study of the detection circulating free DNA (cfDNA) combined with tumor specific mutation detection by digital PCR as a novel minimally invasive biomarker in pancreatic ductal adenocarcinoma (PDAC). This was compared to the detection of CTC by the CellSearch® system and a novel CTC enrichment strategy based on CD45 positive cell depletion. The aim of the study was to assess tumor specific DNA detection in plasma and CTC detection as prognostic markers in PDAC.

RESULTS

We detected KRAS mutant cfDNA in 26% of patients of all stages and this correlated strongly with Overall Survival (OS), 60 days (95% CI: 19-317) for KRAS mutation positive vs 772 days for KRAS mutation negative (95% CI: 416-1127). Although, the presence of CTC detected by the CellSearch® system did correlate significantly with OS, 88 days (95% CI: 27-206) CTC positive vs 393 days CTC negative (95% CI: 284-501), CTC were detected in only 20% of patients, the majority of which had metastatic disease, whereas KRAS mutant cfDNA was detected in patients with both resectable and advanced disease.

CONCLUSIONS

Tumor specific cfDNA detection and CTC detection are promising markers for the management of patients with PDAC, although there is a need to validate these results in a larger patient cohort and optimize the detection of CTC in PDAC by applying the appropriate markers for their detection.

PanGen-Fam: Spanish registry of hereditary pancreatic cancer

PURPOSE

To describe the organisation of the registry and the preliminary results in terms of characteristics of high-risk pancreatic ductal adenocarcinoma (PDAC) families recruited to date and findings of the screening programme. To compare early onset sporadic cases (⩽50 years), sporadic cases (>50 years) and cases with family history of cancer, for PDAC possible risk factors.

METHODS/PATIENTS

Families with hereditary cancer syndromes predisposing to PDAC were recruited from two main sources: Spanish hospitals participating in PanGenEU, a pan-European multicentre case-control study, and their genetic counseling unit. Individuals at high-risk of PDAC were enrolled into a screening programme, consisting of Endoscopic ultrasound, computerised tomography, magnetic resonance imaging. Genetic testing of candidate genes was offered according to each patient's risk.

RESULTS

Among 577 consecutive PDAC cases, recruited via PanGenEU, 36 (6%) had ⩾2 first-degree relative with PDAC: Familial pancreatic cancer (FPC). So far PanGen-Fam has recruited 42 high-risk PDAC families; 25 (60%) had FPC. Five index cases with cancer were positive for BRCA2 and one for BRCA1 germline mutations. In the second year of prospective PDAC screening, one neuroendocrine tumour and a high-grade dysplasia lesion suspicious of carcinoma were diagnosed among 41 high-risk individuals. Furthermore EUS detected chronic-pancreatitis-like parenchymal changes in 15 patients.

CONCLUDING STATEMENT

The identification and recruitment of PDAC high-risk families into the PanGen-Fam registry provides an opportunity to detect early onset cancer and precursor pancreatic cancer lesions at a potentially curative stage and to increase the knowledge of the natural history of the disease.

Pazopanib in pretreated advanced neuroendocrine tumors: a phase II, open-label trial of the Spanish Task Force Group for Neuroendocrine Tumors (GETNE)

BACKGROUND

The management of advanced neuroendocrine tumors (NETs) has recently changed. We assessed the activity of pazopanib after failure of other systemic treatments in advanced NETs.

METHODS

This was a multicenter, open-label, phase II study evaluating pazopanib as a single agent in advanced NETs (PAZONET study). The clinical benefit rate (CBR) at 6 months was the primary end point. Translational correlation of radiological response and progression-free survival (PFS) with circulating and tissue biomarkers was also evaluated.

RESULTS

A total of 44 patients were enrolled. Twenty-five patients (59.5%) were progression-free at 6 months (4 partial responses, 21 stable diseases) with a median PFS of 9.5 months [95% confidence interval (CI) 4.8-14.1]. The CBR varied according to prior therapy received, with 73%, 60% and 25% in patients treated with prior multitarget inhibitors, prior mTOR inhibitors and both agents, respectively. A nonsignificant increase in PFS was observed in patients presenting lower baseline circulating tumor cell (CTC) counts (9.1 versus 5.8 months; P = 0.22) and in those with decreased levels of soluble-vascular endothelial growth factor receptor-2 (sVEGFR-2) (12.6 versus 9.1 months; P = 0.067). A trend toward reduced survival was documented in patients with VEGFR3 rs307821 and rs307826 missense polymorphisms [hazard ratio (HR): 12.3; 95% CI 1.09-139.2; P = 0.042 and HR: 6.9; 95% CI 0.96-49.9; P = 0.055, respectively].

CONCLUSIONS

Pazopanib showed clinical activity in patients with advanced NETs regardless of previous treatments. Additionally, CTCs, soluble-s VEFGR-2 and VEGFR3 gene polymorphisms constitute potential biomarkers for selecting patients for pazopanib (NCT01280201).

CLINICAL TRIAL NUMBER

NCT01280201.

The UBC-40 Urothelial Bladder Cancer cell line index: a genomic resource for functional studies

BACKGROUND

Urothelial bladder cancer is a highly heterogeneous disease. Cancer cell lines are useful tools for its study. This is a comprehensive genomic characterization of 40 urothelial bladder carcinoma (UBC) cell lines including information on origin, mutation status of genes implicated in bladder cancer (FGFR3, PIK3CA, TP53, and RAS), copy number alterations assessed using high density SNP arrays, uniparental disomy (UPD) events, and gene expression.

RESULTS

Based on gene mutation patterns and genomic changes we identify lines representative of the FGFR3-driven tumor pathway and of the TP53/RB tumor suppressor-driven pathway. High-density array copy number analysis identified significant focal gains (1q32, 5p13.1-12, 7q11, and 7q33) and losses (i.e. 6p22.1) in regions altered in tumors but not previously described as affected in bladder cell lines. We also identify new evidence for frequent regions of UPD, often coinciding with regions reported to be lost in tumors. Previously undescribed chromosome X losses found in UBC lines also point to potential tumor suppressor genes. Cell lines representative of the FGFR3-driven pathway showed a lower number of UPD events.

CONCLUSIONS

Overall, there is a predominance of more aggressive tumor subtypes among the cell lines. We provide a cell line classification that establishes their relatedness to the major molecularly-defined bladder tumor subtypes. The compiled information should serve as a useful reference to the bladder cancer research community and should help to select cell lines appropriate for the functional analysis of bladder cancer genes, for example those being identified through massive parallel sequencing.

Primary Sarcomatoid Tumor of the Bladder: A Different Entity but the Same Approach?

Bladder cancer remains a frequent cancer worldwide, and most tumors are diagnosed at localized stages. Urothelial carcinoma (UC) accounts for 90% of bladder cancer cases. Sarcomatoid carcinoma (SaC) of the bladder is a rare variant (0.5% of total bladder cancers) characterized by 2 components based on histology; the epithelial and mesenchymal phenotypes, which can be easily differentiated by immunohistochemistry. SaC has similar epidemiologic features to UC but different behavior, aggressiveness, and prognosis. In this review, we summarize the main differences between UC bladder cancers and SaC subtypes. The therapeutic strategies used in SaC today do not differ much from those used for the urothelial variant. However, there is still no standard treatment--the result of a lack of clinical trials for the sarcomatoid variant. Further multicenter comparative studies are needed to devise a better treatment strategy for patients with this rare histologic tumor subtype.

New insights into Brunner syndrome and potential for targeted therapy

We report two families with Brunner syndrome living in one state of Australia. The first family had a predicted protein-truncating variant of monoamine oxidase A (MAOA) (p.S251KfsX2). Affected males had mild intellectual disability (ID), obsessive behaviour, limited friendships and were introverted and placid during clinical interview. The family disclosed episodic explosive aggression after a diagnosis was made. The second family had a missense variant in MAOA (p.R45W). Affected males had borderline-mild ID, attention deficit disorder and limited friendships. One had a history of explosive aggression in childhood and episodic symptoms of flushing, headaches and diarrhoea. Their carrier mother had normal intelligence but similar episodic symptoms. Characteristic biochemical abnormalities included high serum serotonin and urinary metanephrines and low urinary 5-hydroxyindoleacetic acid (5-HIAA) and vanillylmandelic acid (VMA). Symptomatic individuals in the second family had particularly high serotonin levels, and treatment with a serotonin reuptake inhibitor and dietary modification resulted in reversal of biochemical abnormalities, reduction of 'serotonergic' symptoms and behavioural improvement. Brunner syndrome should be considered as a cause of mild ID with paroxysmal behavioural symptoms. It can be screened for with serum/urine metanephrine and serotonin measurement. Cautious treatment with a serotonin reuptake inhibitor, dietary modifications and avoidance of medications contraindicated in patients on monoamine oxidase inhibitors can improve symptoms.

Biomarkers for early diagnosis of pancreatic cancer

Pancreatic ductal adenocarcinoma is an aggressive malignancy with a 5-year survival rate of approximately 5%. The lack of established strategies for early detection contributes to this poor prognosis. Although several novel candidate biomarkers have been proposed for earlier diagnosis, none have been adopted into routine clinical use. In this review, the authors examine the challenges associated with finding new pancreatic cancer diagnostic biomarkers and explore why translation of biomarker research for patient benefit has thus far failed. The authors also review recent progress and highlight advances in the understanding of the biology of pancreatic cancer that may lead to improvements in biomarker detection and implementation.

Prognostic factors in advanced gastric cancer after second-line treatment

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Background: Advanced gastric cancer (AGC) is a highly lethal disease worldwide with a median overall survival (OS) of less than 12 months. Ramucirumab was the first targeted agent to show survival benefit in the second-line (2L) treatment of AGD. From the REGARD trial, women exhibited a trend towards a worse survival when compared to men. Methods: We retrospectively analyzed the outcome of a Spanish cohort of 55 AGC patients who had received at least two consecutive chemotherapy lines of treatment at our institution. We preselected some clinical parameters (age, gender, Lauren subtype, Her-2 status, grade of differentiation, primary tumor localization and resection, TNM stage, neoadjuvant/adjuvant administration, mono/polychemotherapy in 2L, irinotecan- or taxane-based 2L, Trastuzumab treatment, and administration of third-lines [3L]) to be tested as potential prognostic factors. We focused our analysis on the gender effect in OS after 2L treatment in AGC. The SPSS software package was used for all statistical analyses (Mann-Whitney U test, Chi Square, Kaplan-Meier, Cox regression). Results: Women, diffuse subtype, poorly differentiated tumors, sub-cardia location, single-agent 2L and 3L administration were the clinical characteristics with a significant shorter OS by the univariable analysis. Median OS of women (5 months, 95%CI 3.9-6.0) was significant lower than that in men (13 months, 95%CI 7.9-18.0) by both Log-Rank and Breslow tests (p 0.002). We found no significant differences in age, progression-free survival or time-on-treatment between men and women. Female gender was significantly associated with more taxane-based 2L and with less 3L treatment administration. When 3L treatment administration was excluded in the multivariable analysis, female gender was the only independent prognostic factor of all the clinical parameters included in our review (HR 0.33, 95%CI 0.15-0.75, p 0.008). Conclusions: Our retrospective study found that gender, Lauren subtype, grade of differentiation, primary tumor location, polychemotherapy and 3L administration may be potential prognostic factors in AGC after 2L treatment. Female gender was an independent prognostic factor in our Spanish cohort.

Genetic and phenotypic characterization of families with familial pancreatic cancer and screening of high-risk individuals

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Background: The prognosis of patients diagnosed with Pancreatic Cancer (PC) is dismal with a 5-year survival rate of around 5%. Familial Pancreatic Cancer (FPC) is an autosomal dominant rare syndrome defined as families with two or more first-degree relatives with pancreatic cancer that do not fulfill the criteria of any other inherited tumor syndrome. The Spanish familial pancreatic cancer registry, Pan-Gen-FAM was established in 2009 in order to identify and manage families at high risk of developing PC. Methods: Information on the family history of cancer is collected in order to determine the phenotype of individual families and patients are offered genetic testing of known FPC associated genes pertinent to their familial syndrome. An individualized clinical screening program is devised for the early detection of a pancreatic tumor consisting of periodic monitoring by imaging techniques (EUS and MRI) and the evaluation of minimally-invasive tumor biomarkers approaches including Circulating Tumor Cells (CTC) and circulating free DNA in blood. Results: To date the registry includes 125 individuals representing some 41 families. Of 17 families tested so far BRCA2 germline mutations were detected in 5 families and a BRCA1 mutation in 1 family. 43 individuals underwent clinical screening. More pancreatic abnormalities were found by EUS (41%) than by MRI (31%). The most frequent abnormal findings were parenchymal changes associated with chronic pancreatitis. Eight cystic lesions were identified. One lesion was identified as a well differentiated neuroendocrine tumor and another was shown to have benign cytology and whilst carcinoma was found in a third patient, this patient underwent a subsequent partial pancreatectomy. The remaining patients with cystic lesions are undergoing close clinical observation. Seventy three patients underwent CTC determinations and all patients tested negative. Conclusions: Periodic screening of high risk individuals by EUS and RMI can detect small tumors and premalignant lesions. We hypothesize that these persons will have a higher probability of long-term survival than sporadic cases.

Recurrent inactivation of STAG2 in bladder cancer is not associated with aneuploidy

Urothelial bladder cancer (UBC) is heterogeneous at the clinical, pathological, and genetic levels. Tumor invasiveness (T) and grade (G) are the main factors associated with outcome and determine patient management (1). A discovery exome sequencing screen (n=17), followed by a prevalence screen (n=60), identified new genes mutated in this tumor coding for proteins involved in chromatin modification (MLL2, ASXL2, BPTF), cell division (STAG2, SMC1A, SMC1B), and DNA repair (ATM, ERCC2, FANCA). STAG2, a subunit of cohesin, was significantly and commonly mutated/lost in UBC, mainly in tumors of low stage/grade, and its loss was associated with improved outcome. Loss of expression was often observed in chromosomally-stable tumors and STAG2 knockdown in bladder cancer cells did not increase aneuploidy. STAG2 reintroduction in non-expressing cells led to reduced colony formation. Our findings indicate that STAG2 is a novel UBC tumor suppressor acting through mechanisms that are different from its role to prevent aneuploidy.

Imaging techniques in pancreatic cancer screening: Preliminary results from the PanGen-FAM registry

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Background: The incidence of pancreatic cancer (PC) is low, thus screening is recommended for individuals considered to be at high risk. These include members of families with ≥ 2 relatives with PC (FPC), Peutz Jegher syndrome, hereditary breast/ovarian cancer (HBOC), familial atypical multiple mole melanoma and Lynch syndrome. Previous studies have shown that non-invasive precursor lesions, such as intraductal papillary mucinous neoplasm (IPMN) and pancreatic intraepithelial neoplasia (PanIN) are more common and of a higher invasive grade in patients with a family history of PC. Methods: Baseline screening consisted of endoscopic ultrasound (EUS) and computed tomography (CT) and magnetic resonance imaging (MRI). FNA-EUS was performed when mass lesions or cysts ≥1 cm in size were encountered. The possibility of surgical intervention or ongoing clinical observation was discussed by a multidisciplinary team in the case of abnormal findings. Furthermore Circulating Tumor Cells (CTC) in peripheral blood as a diagnostic marker was assessed. Thirty-five individuals from FPC and HBOC families were screened between October 2011and December 2012. Results: The most frequent abnormal findings by EUS were parenchymal changes found in chronic pancreatitis (hyperechoic foci, echogenic strands, lobularity, cysts). Overall 13 (41%) patients showed at least 1 of these changes; of note, 7 patients were from the same FPC family. Four patients were diagnosed with cystic lesions by EUS; two lesions were confirmed by MRI but not by CT, one lesion was confirmed by both MRI and CT and was compatible with a mucinous tumor < 1cm in diameter and one lesion was detected only by EUS. One patient with cystic lesion >1 cm in size underwent EUS-FNA and the cytology showed benign celularity. One patient has a solid lesion, and it was a neuroendocrine tumor. The remaining patients with cystic lesions were proposed for ongoing close clinical observation. CTC have not been detected in 54 patients tested. Conclusions: A high prevalence of pancreatic abnormalities was found in patients from FPC families. Preliminary data suggest that EUS is the most sensitive method to detect small tumors and premalignant lesions.