Highly Accurate Identification of Cystic Precursor Lesions of Pancreatic Cancer Through Targeted Mass Spectrometry: A Phase IIc Diagnostic Study

Pancreas Cyst Diagnosis and Advances in Cyst Fluid Analysis

Pancreatic Cystic Neoplasms (PCN) represent a diverse group of tumors, some of which may progress to pancreatic cancer. Considering their high prevalence in the general population, the development of reliable biomarkers is crucial. The ideal biomarker will accurately diagnose the subtype of PCN and assess the risk of high-grade dysplasia or invasive cancer. Cyst fluid analysis has emerged as a promising approach to accomplish this goal, yet no single marker has yet gained unanimous support for routine inclusion in PCN evaluation.

The role of biomarkers in the early detection of pancreatic cancer

Pancreatic surveillance can detect early-stage pancreatic cancer and achieve long-term survival, but currently involves annual endoscopic ultrasound and MRI/MRCP, and is recommended only for individuals who meet familial/genetic risk criteria. To improve upon current approaches to pancreatic cancer early detection and to expand access, more accurate, inexpensive, and safe biomarkers are needed, but finding them has remained elusive. Newer approaches to early detection, such as using gene tests to personalize biomarker interpretation, and the increasing application of artificial intelligence approaches to integrate complex biomarker data, offer promise that clinically useful biomarkers for early pancreatic cancer detection are on the horizon.

Emerging Technologies in Endoscopy for Gastrointestinal Neoplasms: A Comprehensive Overview

Gastrointestinal neoplasms are a growing global health concern, requiring prompt identification and treatment. Endoscopic procedures have revolutionized the detection and treatment of gastrointestinal tumors by providing accurate, minimally invasive methods. Early-stage malignancies can be treated with endoscopic excision, leading to improved outcomes and increased survival rates. Precancerous lesions, like adenomatous polyps, can be prevented by removing them, reducing cancer occurrence and death rates. Advanced techniques like chromoendoscopy, narrow-band imaging, and confocal laser endomicroscopy improve the ability to see the mucosa surface and diagnose conditions. Artificial Intelligence (AI) applications in endoscopy can enhance diagnostic accuracy and predict histology outcomes. However, challenges remain in accurately defining lesions and ensuring precise diagnosis and treatment selection. Molecular imaging approaches and therapeutic modalities like photodynamic therapy and endoscopic ultrasonography-guided therapies hold potential but require further study and clinical confirmation. This study examines the future prospects and obstacles in endoscopic procedures for the timely identification and treatment of gastrointestinal cancers. The focus is on developing technology, limits, and prospective effects on clinical practice.

Revisiting the performance of cyst fluid carcinoembryonic antigen as a diagnostic marker for pancreatic mucinous cysts: a comprehensive 20-year institutional review

OBJECTIVE

Elevated pancreatic cyst fluid carcinoembryonic antigen (CEA) has been routinely used to classify mucinous cysts. This study incorporates original data that established the CEA ≥192 ng/mL threshold with over 20 years of additional data and reassesses the diagnostic performance of CEA for differentiating mucinous from non-mucinous cysts.

DESIGN

1169 pancreatic cysts (1999-2021) with CEA results were identified. 394 cases had histological confirmation as the diagnostic standard. Additionally, 237 cysts without histological confirmation demonstrated KRAS, GNAS, or RNF43 mutations by molecular testing and were combined with the histologically confirmed cysts for separate analysis on a total cohort of 631 cysts.

RESULTS

Median CEA was significantly higher in mucinous cysts (323.9 ng/mL, n=314) versus non-mucinous cysts (204.6 ng/mL, n=80) (p<0.001). Receiver operating characteristic curve analysis demonstrated an optimal CEA cut-off of 20 ng/mL (area under the curve: 80%), though the specificity was lower than desired (sensitivity 89%, specificity 64%). At the previously established threshold of 192 ng/mL, sensitivity and specificity were 56% and 78%, respectively. To achieve a specificity of 85% as originally reported, a CEA threshold of 250 ng/mL was needed; the 13 false positive cases at this threshold included 4 benign simple cysts, 2 squamoid cysts, 1 serous cystadenoma, 1 lymphoepithelial cyst and 5 more uncommon entities. All results remained similar within the total cohort after including additional cases with KRAS/GNAS/RNF43 mutations only.

CONCLUSION

Cyst fluid CEA continues to be a useful test in the diagnosis of mucinous pancreatic cysts but does not appear as specific as previously reported. Raising the CEA threshold to 250 ng/mL to maintain specificity for differentiating mucinous from non-mucinous cysts may be considered.

Tumor suppressor CLCA1 inhibits angiogenesis via TGFB1/SMAD/VEGF cascade and sensitizes hepatocellular carcinoma cells to Sorafenib

BACKGROUND

Hepatocellular carcinoma (HCC) is a highly vascularized tumor with a poor prognosis. Novel vascular-related therapeutic targets and prognostic markers remain urgently needed.

AIMS

To investigate the role and mechanism of CLCA1 in hepatocellular carcinoma.

METHODS

Immunofluorescence, Co-immunoprecipitation and rescue experiment were used to determine the specific mechanisms of CLCA1. Chemosensitivity assay was used to measure the impact of CLCA1 on Sorafenib.

RESULTS

CLCA1 was dramatically downregulated in hepatocellular carcinoma cell lines and tissues. Ectopic expression of CLCA1 induced cell apoptosis and G0/G1 phase arrest while suppressed cell growth, inhibited migration and invasion, reversal of epithelial mesenchymal transition in vitro and reduced xenograft tumor growth in vivo. Mechanistically, CLCA1 could co-localize and interact with TGFB1, thereby suppressing HCC angiogenesis through the TGFB1/SMAD/VEGF signaling cascade in vitro and in vivo. Moreover, CLCA1 also enhanced the sensitivity of HCC cells to the first-line targeted therapy, Sorafenib.

CONCLUSION

CLCA1 sensitizes HCC cells to Sorafenib and suppresses hepatocellular carcinoma angiogenesis through downregulating TGFB1 signaling cascade. This newly identified CLCA1 signaling pathway may help guide the anti-angiogenesis therapies for hepatocellular carcinoma. We also support the possibility of CLCA1 being a prognostic biomarker for hepatocellular carcinoma.

Predictive ability of pancreatic cyst fluid biomarkers: A systematic review and meta-analysis

BACKGROUND

Mucinous pancreatic cysts harbor the potential to progress to highly lethal pancreatic ductal adenocarcinoma (PDAC). Since these precursor cysts require cancer surveillance or surgical resection, they need to be reliably distinguished from harmless pancreatic cysts. Current clinical and radiographic assessment is imperfect and the value of cyst fluid analysis for differential diagnosis is unclear. Therefore, we set out to investigate the value of cyst fluid biomarkers in distinguishing pancreatic cysts.

METHODS

We performed a systematic review of the current literature to identify articles that evaluated the diagnostic performance of clinically relevant and promising candidate cyst fluid biomarkers, with a particular emphasis on DNA-based biomarkers. Meta-analysis was performed for biomarkers targeted at identifying cyst type and presence of high-grade dysplasia or PDAC.

RESULTS

Data from a total of 42 studies was analyzed. Mutations in KRAS and/or GNAS allowed identification of mucinous cysts with a sensitivity of 79% and specificity of 98%. This exceeded the performance of the traditional biomarker carcinoembryonic antigen (CEA; sensitivity 58%, specificity 87%). Mutations in VHL were specific for serous cystadenomas (SCAs; sensitivity 56%, specificity 99%) and help to exclude mucinous cysts. Mutations in CDKN2A, PIK3CA, SMAD4, and TP53 each had high specificities of 97%, 97%, 98%, and 95%, respectively, to identify high-grade dysplasia or PDAC in mucinous cysts.

CONCLUSIONS

Cyst fluid analysis can be a valuable tool in the characterization of pancreatic cysts, with relevant clinical implications. Our results support the use of DNA-based cyst fluid biomarkers in the multidisciplinary diagnostic work-up of pancreatic cysts.

Proteomics: Its Promise and Pitfalls in Shaping Precision Medicine in Solid Organ Transplantation

Solid organ transplantation is an established treatment of choice for end-stage organ failure. However, all transplant patients are at risk of developing complications, including allograft rejection and death. Histological analysis of graft biopsy is still the gold standard for evaluation of allograft injury, but it is an invasive procedure and prone to sampling errors. The past decade has seen an increased number of efforts to develop minimally invasive procedures for monitoring allograft injury. Despite the recent progress, limitations such as the complexity of proteomics-based technology, the lack of standardization, and the heterogeneity of populations that have been included in different studies have hindered proteomic tools from reaching clinical transplantation. This review focuses on the role of proteomics-based platforms in biomarker discovery and validation in solid organ transplantation. We also emphasize the value of biomarkers that provide potential mechanistic insights into the pathophysiology of allograft injury, dysfunction, or rejection. Additionally, we forecast that the growth of publicly available data sets, combined with computational methods that effectively integrate them, will facilitate a generation of more informed hypotheses for potential subsequent evaluation in preclinical and clinical studies. Finally, we illustrate the value of combining data sets through the integration of 2 independent data sets that pinpointed hub proteins in antibody-mediated rejection.

Pancreatic Cystic Lesions: A Focused Review on Cyst Clinicopathological Features and Advanced Diagnostics

Macroscopic, endomicroscopic, and histologic findings and correlation are an integral part of the diagnostic evaluation of pancreatic cystic lesions (PCLs), as complementing morphologic features seen by different specialties are combined to contribute to a final diagnosis. However, malignancy risk stratification of PCLs with worrisome features can still be challenging even after endoscopic ultrasound guided-fine needle aspiration (EUS-FNA) with cytological evaluation. This review aims to summarize cyst clinicopathological features from the pathologists' perspective, coupled with knowledge from advanced diagnostics-confocal laser endomicroscopy and cyst fluid molecular analysis, to demonstrate the state-of-art risk stratification of PCLs. This review includes illustrative photos of surgical specimens, endomicroscopic and histologic images, and a summary of cyst fluid molecular markers.

Biochemical Intracystic Biomarkers in the Differential Diagnosis of Pancreatic Cystic Lesions

Background and Objectives: Pancreatic cystic lesions (PCLs) are frequently incidental findings. The prevalence of PCLs is increasing, mainly due to advancements in imaging techniques, but also because of the aging of the population. PCLs comprise challenging clinical problems, as their manifestations vary from benign to malignant lesions. Therefore, the recognition of PCLs is achieved through a complex diagnostic and surveillance process, which in turn is usually long-term, invasive, and expensive. Despite the progress made in the identification of novel biomarkers in the cystic fluid that also support the differentiation of PCLs, their application in clinical practice is limited. Materials and Methods: We conducted a systematic review of the literature published in two databases, Pubmed and Embase, on biochemical biomarkers in PCLs that may be applied in the diagnostic algorithms of PCLs. Results: Eleven studies on intracystic glucose, twenty studies on intracystic carcinoembryonic antigen (CEA), and eighteen studies on other biomarkers were identified. Low levels of intracystic glucose had high sensitivity and specificity in the differentiation between mucinous and non-mucinous cystic neoplasms. Conclusions: CEA and glucose are the most widely studied fluid biochemical markers in pancreatic cystic lesions. Glucose has better diagnostic accuracy than CEA. Other biochemical biomarkers require further research.

Current status and future perspectives of clinical research in pancreatic cancer: Establishment of evidence by science

Pancreatic cancer is one of the most aggressive diseases in the world due to a lack of early detection, leading to an overall 5-year survival of only 10%. In recent years, clinical trials targeted pancreatic cancer in efforts to improve survival. These studies introduce new technologies, concepts, and evidence which have instilled new optimism for improving prognosis. This review summarizes the current status of the recent (5-year) clinical trials and describes contemporary research on pancreatic cancer, including surgical technology, diagnostic skills, traditional chemoradiotherapy, neoadjuvant chemotherapy, immunotherapy, targeted therapy, and precision medicine. Then, the future trend and direction of clinical trials on pancreatic cancer are discussed.

De novo expression of gastrokines in pancreatic precursor lesions impede the development of pancreatic cancer

Molecular events occurring in stepwise progression from pre-malignant lesions (pancreatic intraepithelial neoplasia; PanIN) to the development of pancreatic ductal adenocarcinoma (PDAC) are poorly understood. Thus, characterization of early PanIN lesions may reveal markers that can help in diagnosing PDAC at an early stage and allow understanding the pathology of the disease. We performed the molecular and histological assessment of patient-derived PanINs, tumor tissues and pancreas from mouse models with PDAC (KC mice that harbor K-RAS mutation in pancreatic tissue), where we noted marked upregulation of gastrokine (GKN) proteins. To further understand the role of gastrokine proteins in PDAC development, GKN-deficient KC mice were developed by intercrossing gastrokine-deficient mice with KC mice. Panc-02 (pancreatic cancer cells of mouse origin) were genetically modified to express GKN1 for further in vitro and in vivo analysis. Our results show that gastrokine proteins were absent in healthy pancreas and invasive cancer, while its expression was prominent in low-grade PanINs. We could detect these proteins in pancreatic juice and serum of KC mice. Furthermore, accelerated PanIN and tumor development were noted in gastrokine deficient KC mice. Loss of gastrokine 1 protein delayed apoptosis during carcinogenesis leading to the development of desmoplastic stroma while loss of gastrokine 2 increased the proliferation rate in precursor lesions. In summary, we identified gastrokine proteins in early pancreatic precursor lesions, where gastrokine proteins delay pancreatic carcinogenesis.

Sulfation of O-glycans on Mucin-type Proteins From Serous Ovarian Epithelial Tumors

Despite sulfated O-linked glycans being abundant on ovarian cancer (OC) glycoproteins, their regulation during cancer development and involvement in cancer pathogenesis remain unexplored. We characterized O-glycans carrying sulfation on galactose residues and compared their expression with defined sulfotransferases regulated during OC development. Desialylated sulfated oligosaccharides were released from acidic glycoproteins in the cyst fluid from one patient with a benign serous cyst and one patient with serous OC. Oligosaccharides characterized by LC-MSⁿ were identified as core 1 and core 2 O-glycans up to the size of decamers and with 1 to 4 sulfates linked to GlcNAc residues and to C-3 and/or C-6 of Gal. To study the specificity of the potential ovarian sulfotransferases involved, Gal3ST2 (Gal-3S)-, Gal3ST4 (Gal-3S)-, and CHST1 (Gal-6S)-encoding expression plasmids were transfected individually into CHO cells also expressing the P-selectin glycoprotein ligand-1/mouse immunoglobulin G2b (PSGL-1/mIg G2b) fusion protein and the human core 2 transferase (GCNT1). Characterization of the PSGL-1/mIg G2b O-glycans showed that Gal3ST2 preferentially sulfated Gal on the C-6 branch of core 2 structures and Gal3ST4 preferred Gal on the C-3 branch independently if core-1 or -2. CHST1 sulfated Gal residues on both the C-3 (core 1/2) and C-6 branches of core 2 structures. Using serous ovarian tissue micro array, Gal3ST2 was found to be decreased in tissue classified as malignant compared with tissues classified as benign or borderline, with the lowest expression in poorly differentiated malignant tissue. Neither Gal3ST4 nor CHST1 was differentially expressed in benign, borderline, or malignant tissue, and there was no correlation between expression level and differentiation stage. The data displays a complex sulfation pattern of O-glycans on OC glycoproteins and that aggressiveness of the cancer is associated with a decreased expression of the Gal3ST2 transferase.

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Ovarian cancer tissue contains highly sulfated O-glycoproteins.

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Sulfation occurs on GlcNAc (6-position) and Gal (3- and 6-position).

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Sulfation of Gal can be mimicked recombinantly with selected sulfotransferase.

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The Gal3ST2 sulfotransferase level is lower in malignant cancer compared with benign.

Biomarkers in the diagnosis of pancreatic cancer: Are we closer to finding the golden ticket?

Pancreatic cancer (PC) is a leading cause of cancer related mortality on a global scale. The disease itself is associated with a dismal prognosis, partly due to its silent nature resulting in patients presenting with advanced disease at the time of diagnosis. To combat this, there has been an explosion in the last decade of potential candidate biomarkers in the research setting in the hope that a diagnostic biomarker may provide a glimmer of hope in what is otherwise quite a substantial clinical dilemma. Currently, serum carbohydrate antigen 19-9 is utilized in the diagnostic work-up of patients diagnosed with PC however this biomarker lacks the sensitivity and specificity associated with a gold-standard marker. In the search for a biomarker that is both sensitive and specific for the diagnosis of PC, there has been a paradigm shift towards a focus on liquid biopsy and the use of diagnostic panels which has subsequently proved to have efficacy in the diagnosis of PC. Currently, promising developments in the field of early detection on PC using diagnostic biomarkers include the detection of microRNA (miRNA) in serum and circulating tumour cells. Both these modalities, although in their infancy and yet to be widely accepted into routine clinical practice, possess merit in the early detection of PC. We reviewed over 300 biomarkers with the aim to provide an in-depth summary of the current state-of-play regarding diagnostic biomarkers in PC (serum, urinary, salivary, faecal, pancreatic juice and biliary fluid).

High-Risk Characteristics Associated with Advanced Pancreatic Cystic Lesions: Results from a Retrospective Surgical Cohort

BACKGROUND AND AIM

The management of pancreatic cystic lesions (PCLs) remains controversial. We performed a retrospective study to determine characteristics associated with advanced PCLs (A-PCLs) and whether these characteristics vary in different pathological types of PCLs. The additional diagnostic value of endoscopic ultrasound (EUS) was also evaluated.

METHODS

Patients who underwent surgical resection for an identified PCLs by imaging modalities were included. A logistic regression model was developed to identify significant characteristics for A-PCLs. EUS data was assessed separately.

RESULTS

Three hundred and fifty-three patients were included, and 125 patients (35.4%) were A-PCLs. The presence of main pancreatic duct (MPD) diameter ≥ 10 mm (odds ratio [OR], 11.7; 95% confidence interval [CI], 1.53-89.2; P = 0.018), mural nodules ≥ 5 mm (OR, 11.67; 95% CI, 2.3-59.05; P = 0.003), solid components within cysts (OR, 30.87; 95% CI, 7.23-131.7; P < 0.0001) and high serum CA19-9 levels (OR, 1.006; 95% CI, 1.001-1.011; P = 0.02) were independently associated with the presence of A-PCLs. The presence of septa was independently associated with the presence of non-A-PCLs (OR, 0.147; 95% CI, 0.04-0.6; P = 0.008). Males who had a history of tobacco abuse (P < 0.0001) and had a greatly dilated MPD (P < 0.0001) were more common in advanced intraductal papillary mucinous neoplasms (IPMC) patients. Solid pseudopapillary neoplasm (SPT) often occurred in young women (P < 0.0001), mostly asymptomatically (P < 0.0001) and with lower serum CA19-9 levels (P < 0.0001). In the 124 patients who underwent EUS-guided fine-needle aspiration (EUS-FNA), five additional characteristics (4 mural nodules and 1 MPD involvement) were identified by EUS imaging and 17 patients were identified with abnormal cytological results (13 atypical cells and 4 suspicious for malignancy cells) by EUS-FNA.

CONCLUSION

On the basis of a retrospective study with large sample size, the presence of MPD ≥ 10 mm, mural nodules, solid components, and high serum CA19-9 levels were independently associated with the presence of A-PCLs. The high-risk characteristics may vary across different types of A-PCLs. EUS and EUS-FNA could provide additional diagnostic information for PCLs.

Extracellular Vesicle Analysis Allows for Identification of Invasive IPMN

BACKGROUND AND AIMS

Advances in cross-sectional imaging have resulted in increased detection of intraductal papillary mucinous neoplasms (IPMNs), and their management remains controversial. At present, there is no reliable noninvasive method to distinguish between indolent and high risk IPMNs. We performed extracellular vesicle (EV) analysis to identify markers of malignancy in an attempt to better stratify these lesions.

METHODS

Using a novel ultrasensitive digital extracellular vesicle screening technique (DEST), we measured putative biomarkers of malignancy (MUC1, MUC2, MUC4, MUC5AC, MUC6, Das-1, STMN1, TSP1, TSP2, EGFR, EpCAM, GPC1, WNT-2, EphA2, S100A4, PSCA, MUC13, ZEB1, PLEC1, HOOK1, PTPN6, and FBN1) in EV from patient-derived cell lines and then on circulating EV obtained from peripheral blood drawn from patients with IPMNs. We enrolled a total of 133 patients in two separate cohorts: a clinical discovery cohort (n = 86) and a validation cohort (n = 47).

RESULTS

From 16 validated EV proteins in plasma samples collected from the discovery cohort, only MUC5AC showed significantly higher levels in high-grade lesions. Of the 11 patients with invasive IPMN (inv/HG), 9 had high MUC5AC expression in plasma EV of the 11 patients with high-grade dysplasia alone, only 1 had high MUC5AC expression (sensitivity of 82%, specificity of 100%). These findings were corroborated in a separate validation cohort. The addition of MUC5AC as a biomarker to imaging and high-riskstigmata allowed detection of all cases requiring surgery, whereas imaging and high-risk stigmata alone would have missed 5 of 14 cases (36%).

CONCLUSIONS

MUC5AC in circulating EV can predict the presence of invasive carcinoma within IPMN. This approach has the potential to improve the management and follow-up of patients with IPMN including avoiding unnecessary surgery.

Epithelial Nr5a2 heterozygosity cooperates with mutant Kras in the development of pancreatic cystic lesions

Cystic neoplasms of the pancreas are an increasingly important public health problem. The majority of these lesions are benign but some progress to invasive pancreatic ductal adenocarcinoma (PDAC). There is a dearth of mouse models of these conditions. The orphan nuclear receptor NR5A2 regulates development, differentiation, and inflammation. Germline Nr5a2 heterozygosity sensitizes mice to the oncogenic effects of mutant Kras in the pancreas. Here, we show that - unlike constitutive Nr5a2^+/- mice - conditional Nr5a2 heterozygosity in pancreatic epithelial cells, combined with mutant Kras (KPN^+/- ), leads to a dramatic replacement of the pancreatic parenchyma with cystic structures and an accelerated development of high-grade PanINs and PDAC. Timed histopathological analyses indicated that in KPN^+/- mice PanINs precede the formation of cystic lesions and the latter precede PDAC. A single episode of acute caerulein pancreatitis is sufficient to accelerate the development of cystic lesions in KPN^+/- mice. Epithelial cells of cystic lesions of KPN^+/- mice express MUC1, MUC5AC, and MUC6, but lack expression of MUC2, CDX2, and acinar markers, indicative of a pancreato-biliary/gastric phenotype. In accordance with this, in human samples we found a non-significantly decreased expression of NR5A2 in mucinous tumours, compared with conventional PDAC. These results highlight that the effects of loss of one Nr5a2 allele are time- and cell context-dependent. KPN^+/- mice represent a new model to study the formation of cystic pancreatic lesions and their relationship with PanINs and classical PDAC. Our findings suggest that pancreatitis could also contribute to acceleration of cystic tumour progression in patients. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Application of EUS-based techniques in the evaluation of pancreatic cystic neoplasms

Pancreatic cystic neoplasms (PCNs) are being detected increasingly frequently due to the widespread use of high-resolution abdominal imaging modalities. Some subtypes of PCNs have the potential for malignant transformation. Therefore, accurate diagnosis of PCNs is crucial to determine whether surgical resection or surveillance is the best management strategy. However, the current cross-section imaging modalities are not accurate enough to enable definite diagnoses. In the last decade, EUS-based techniques have emerged, aiming to overcome the limitations of standard cross-section imaging modalities. These novel EUS-based techniques were primarily designed to acquire distinct images to make radiological diagnoses, collect cyst fluid to undergo biochemical or molecular analyses, and obtain tissue to conclude the pathological diagnoses. In this article, we present a comprehensive and critical review of these emerging EUS techniques for the diagnosis of PCNs, with emphasis being placed on the advantages, feasibilities, diagnostic performances, and limitations of these novel techniques.

The Extracellular Matrix-Derived Biomarkers for Diagnosis, Prognosis, and Personalized Therapy of Malignant Tumors

The tumor biomarkers already have proven clinical value and have become an integral part in cancer management and modern translational oncology. The tumor tissue microenvironment (TME), which includes extracellular matrix (ECM), signaling molecules, immune and stromal cells, and adjacent non-tumorous tissue, contributes to cancer pathogenesis. Thus, TME-derived biomarkers have many clinical applications. This review is predominately based on the most recent publications (manuscripts published in a last 5 years, or seminal publications published earlier) and fills a gap in the current literature on the cancer biomarkers derived from the TME, with particular attention given to the ECM and products of its processing and degradation, ECM-associated extracellular vesicles (EVs), biomechanical characteristics of ECM, and ECM-derived biomarkers predicting response to the immunotherapy. We discuss the clinical utility of the TME-incorporating three-dimensional in vitro and ex vivo cell culture models for personalized therapy. We conclude that ECM is a critical driver of malignancies and ECM-derived biomarkers should be included in diagnostics and prognostics panels of markers in the clinic.

EUS is accurate in characterizing pancreatic cystic lesions; a prospective comparison with cross-sectional imaging in resected cases

Background

Imaging modalities for characterizing pancreatic cystic lesions (PCLs) is a known uncertainty. The aim of this prospective study was to compare the diagnostic performance of endoscopic ultrasound morphology, cytology and cyst fluid carcinoembryonic antigen (EUS-FNA-CEA) with cross-sectional imaging in resected PCLs.

Methods

The cross-sectional imaging and EUS-FNA-CEA results were collected in an academic tertiary referral centre using histology of the surgical specimen as the diagnostic standard.

Results

Of 289 patients undergoing evaluation for PCL with cross-sectional imaging and EUS-FNA between February 2007 and March 2017, 58 underwent surgical resection providing a final diagnosis of the PCLs: 45 mucinous, 5 serous, 1 pseudocyst, 2 endocrine, 2 solid pseudopapillary neoplasms and 3 other. EUS-FNA-CEA was more accurate than cross-sectional imaging in diagnosing mucinous PCLs (95% vs. 83%, p = 0.04). Ninety-two percent of the PCLs with high-grade dysplasia or adenocarcinoma were smaller than 3 cm in diameter. The sensitivity of EUS-FNA-CEA and cross-sectional imaging for detecting PCLs with high-grade dysplasia or adenocarcinoma were 33% and 5% (p = 0.03), respectively. However, there was no difference in accuracy between the modalities (62% vs. 66%, p = 0.79). The sensitivity for detecting pancreatic adenocarcinomas only was 64% for EUS-FNA-CEA and 9% for cross-sectional imaging (p = 0.03). Overall, EUS-FNA-CEA provided a correct diagnosis in more patients with PCLs than cross-sectional imaging (72% vs. 50%, p = 0.01).

Conclusions

EUS-FNA-CEA is accurate and should be considered a complementary test in the diagnosis of PCLs. However, the detection of PCLs with high-grade dysplasia or adenocarcinoma needs to be improved. Cyst size does not seem to be a reliable predictor of high-grade dysplasia or adenocarcinoma.

Electronic supplementary material

The online version of this article (10.1007/s00464-020-08166-3) contains supplementary material, which is available to authorized users.

Advances on diagnostic biomarkers of pancreatic ductal adenocarcinoma: A systems biology perspective

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy that is usually diagnosed at an advanced stage when curative surgery is no longer an option. Robust diagnostic biomarkers with high sensitivity and specificity for early detection are urgently needed. Systems biology provides a powerful tool for understanding diseases and solving challenging biological problems, allowing biomarkers to be identified and quantified with increasing accuracy, sensitivity, and comprehensiveness. Here, we present a comprehensive overview of efforts to identify biomarkers of PDAC using genomics, transcriptomics, proteomics, metabonomics, and bioinformatics. Systems biology perspective provides a crucial “network” to integrate multi-omics approaches to biomarker identification, shedding additional light on early PDAC detection.

Ion Channel Signature in Healthy Pancreas and Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer-related deaths in United States and Europe. It is predicted that PDAC will become the second leading cause of cancer-related deaths during the next decades. The development of PDAC is not well understood, however, studies have shown that dysregulated exocrine pancreatic fluid secretion can contribute to pathologies of exocrine pancreas, including PDAC. The major roles of healthy exocrine pancreatic tissue are secretion of enzymes and bicarbonate rich fluid, where ion channels participate to fine-tune these biological processes. It is well known that ion channels located in the plasma membrane regulate multiple cellular functions and are involved in the communication between extracellular events and intracellular signaling pathways and can function as signal transducers themselves. Hereby, they contribute to maintain resting membrane potential, electrical signaling in excitable cells, and ion homeostasis. Despite their contribution to basic cellular processes, ion channels are also involved in the malignant transformation from a normal to a malignant phenotype. Aberrant expression and activity of ion channels have an impact on essentially all hallmarks of cancer defined as; uncontrolled proliferation, evasion of apoptosis, sustained angiogenesis and promotion of invasion and migration. Research indicates that certain ion channels are involved in the aberrant tumor growth and metastatic processes of PDAC. The purpose of this review is to summarize the important expression, localization, and function of ion channels in normal exocrine pancreatic tissue and how they are involved in PDAC progression and development. As ion channels are suggested to be potential targets of treatment they are furthermore suggested to be biomarkers of different cancers. Therefore, we describe the importance of ion channels in PDAC as markers of diagnosis and clinical factors.

Marker Identification of the Grade of Dysplasia of Intraductal Papillary Mucinous Neoplasm in Pancreatic Cyst Fluid by Quantitative Proteomic Profiling

The incidence of patients with pancreatic cystic lesions, particularly intraductal papillary mucinous neoplasm (IPMN), is increasing. Current guidelines, which primarily consider radiological features and laboratory data, have had limited success in predicting malignant IPMN. The lack of a definitive diagnostic method has led to low-risk IPMN patients undergoing unnecessary surgeries. To address this issue, we discovered IPMN marker candidates by analyzing pancreatic cystic fluid by mass spectrometry. A total of 30 cyst fluid samples, comprising IPMN dysplasia and other cystic lesions, were evaluated. Mucus was removed by brief sonication, and the resulting supernatant was subjected to filter-aided sample preparation and high-pH peptide fractionation. Subsequently, the samples were analyzed by LC-MS/MS. Using several bioinformatics tools, such as gene ontology and ingenuity pathway analysis, we detailed IPMNs at the molecular level. Among the 5834 proteins identified in our dataset, 364 proteins were differentially expressed between IPMN dysplasia. The 19 final candidates consistently increased or decreased with greater IPMN malignancy. CD55 was validated in an independent cohort by ELISA, Western blot, and IHC, and the results were consistent with the MS data. In summary, we have determined the characteristics of pancreatic cyst fluid proteins and discovered potential biomarkers for IPMN dysplasia.

Molecular Diagnosis of Cystic Neoplasms of the Pancreas: a Review

BACKGROUND

The prevalence of incidental pancreatic cystic neoplasms (PCNs) has increased dramatically with advancements in cross-sectional imaging. Diagnostic imaging is limited in differentiating between benign and malignant PCNs. The aim of this review is to provide an overview of biomarkers that can be used to distinguish PCNs.

METHODS

A review of the literature on molecular diagnosis of cystic neoplasms of the pancreas was performed.

RESULTS

Pancreatic cysts can be categorized into inflammatory and non-inflammatory lesions. Inflammatory cysts include pancreatic pseudocysts. Noninflammatory lesions include both mucinous and non-mucinous lesions. Mucinous lesions include intraductal papillary mucinous neoplasm (IPMN) and mucinous cystic neoplasm. Non-mucinous lesions include serous cystadenoma and solid-pseudopapillary tumor of the pancreas. Imaging, cyst aspiration, and histologic findings, as well as carcinoembryonic antigen and amylase are commonly used to distinguish between cyst types. However, molecular techniques to detect differences in genetic mutations, protein expression, glycoproteomics, and metabolomic profiling are important developments in distinguishing between cyst types.

DISCUSSION

Nomograms incorporating common clinical, laboratory, and imaging findings have been developed in a better effort to predict malignant IPMN. The incorporation of top molecular biomarker candidates to nomograms may improve the predictive ability of current models to more accurately diagnose malignant PCNs.

Observation or resection of pancreatic intraductal papillary mucinous neoplasm: An ongoing tug of war

An increasing number of patients are being referred to pancreatic centres around the world due to often incidentally discovered cystic neoplasms of the pancreas. The evaluation and management of pancreatic cystic neoplasms is a controversial topic and with existing guidelines based on a lack of strong evidence there is discordance between centres and guidelines with regard to when to offer surgery and when to favour surveillance. The frequency, duration and modality of surveillance is also controversial as this is resource-consuming and must be balanced against the perceived benefits and risks involved. While there is consensus that the risk of malignancy should be balanced against the life-expectancy and comorbidities, the indications for surgery and surveillance strategies vary among the guidelines. Thus, the tug of war between surveillance or resection continues. Here we discuss the recommendations from guidelines with further accumulating data and emerging reports on intraductal papillary mucinous neoplasm in the literature.

Elevating pancreatic cystic lesion stratification: Current and future pancreatic cancer biomarker(s)

Pancreatic ductal adenocarcinoma (PDAC) is an incredibly deadly disease with a 5-year survival rate of 9%. The presence of pancreatic cystic lesions (PCLs) confers an increased likelihood of future pancreatic cancer in patients placing them in a high-risk category. Discerning concurrent malignancy and risk of future PCL progression to cancer must be carefully and accurately determined to improve survival outcomes and avoid unnecessary morbidity of pancreatic resection. Unfortunately, current image-based guidelines are inadequate to distinguish benign from malignant lesions. There continues to be a need for accurate molecular and imaging biomarker(s) capable of identifying malignant PCLs and predicting the malignant potential of PCLs to enable risk stratification and effective intervention management. This review provides an update on the current status of biomarkers from pancreatic cystic fluid, pancreatic juice, and seromic molecular analyses and discusses the potential of radiomics for differentiating PCLs harboring cancer from those that do not.

Cross Validation of the Monoclonal Antibody Das-1 in Identification of High-Risk Mucinous Pancreatic Cystic Lesions

BACKGROUND & AIMS

Although pancreatic cystic lesions (PCLs) are frequently and incidentally detected, it is a challenge to determine their risk of malignancy. In immunohistochemical and enzyme-linked immunosorbent assay (ELISA) analyses of tissue and cyst fluid from pancreatic intraductal papillary mucinous neoplasms, the monoclonal antibody Das-1 identifies those at risk for malignancy with high levels of specificity and sensitivity. We aimed to validate the ability of Das-1 to identify high-risk PCLs in comparison to clinical guidelines and clinical features, using samples from a multicenter cohort.

METHODS

We obtained cyst fluid samples of 169 PCLs (90 intraductal papillary mucinous neoplasms, 43 mucinous cystic neoplasms, and 36 non-mucinous cysts) from patients undergoing surgery at 4 tertiary referral centers (January 2010 through June 2017). Histology findings from surgical samples, analyzed independently and centrally re-reviewed in a blinded manner, were used as the reference standard. High-risk PCLs were those with invasive carcinomas, high-grade dysplasia, or intestinal-type intraductal papillary mucinous neoplasms with intermediate-grade dysplasia. An ELISA with Das-1 was performed in parallel using banked cyst fluid samples. We evaluated the biomarker's performance, generated area under the curve values, and conducted multivariate logistic regression using clinical and pathology features.

RESULTS

The ELISA for Das-1 identified high-risk PCLs with 88% sensitivity, 99% specificity, and 95% accuracy, at a cutoff optical density value of 0.104. In 10-fold cross-validation analysis with 100 replications, Das-1 identified high-risk PCLs with 88% sensitivity and 98% specificity. The Sendai, Fukuoka, and American Gastroenterological Association guideline criteria identified high-risk PCLs with 46%, 52%, and 74% accuracy (P for comparison to Das-1 ELISA <.001). When we controlled for Das-1 in multivariate regression, main pancreatic duct dilation >5 mm (odds ratio, 14.98; 95% confidence interval, 2.63-108; P < .0012), main pancreatic duct dilation ≥1 cm (odds ratio, 47.9; 95% confidence interval, 6.39-490; P < .0001), and jaundice (odds ratio, 6.16; 95% confidence interval, 1.08-36.7; P = .0397) were significantly associated with high-risk PCLs.

CONCLUSIONS

We validated the ability of an ELISA with the monoclonal antibody Das-1 to detect PCLs at risk for malignancy with high levels of sensitivity and specificity. This biomarker might be used in conjunction with clinical guidelines to identify patients at risk for malignancy.

Diagnosis and management of pancreatic cystic neoplasms

This review outlines the current classification of pancreatic cystic lesions, with a particular emphasis on pancreatic cystic neoplasms (PCNs). It will describe the diagnostic approach to PCNs, with reference to clinicopathological features, cross-sectional radiology and endoscopic ultrasound. This review will conclude with an evidence-based discussion of the management of PCNs focused on recent clinical guidelines.

Proteomics Approaches to Define Senescence Heterogeneity and Chemotherapy Response

In primary cells, senescence induces a permanent proliferative arrest to prevent the propagation of malignant cells. However, the outcome of senescence is more complex in advanced cancer cells where senescent states are heterogeneous. Here, this heterogeneity is discussed and it is proposed that proteomic analysis should be used to identify specific signatures of cancer cells that use this pathway as an adaptive mechanism. Since senescent cells produce an inflammatory secretome, MRM approaches and quantification with internal standards might be particularly suited to follow the expression of the corresponding markers in body fluids. Used in combination with imaging medical technics, a better characterization of senescence heterogeneity should help to monitor the response to chemotherapy treatment.

Appropriateness of pancreatic resection in high-risk individuals for familial pancreatic ductal adenocarcinoma: a patient-level meta-analysis and proposition of the Beaujon score

Background

About 5% of pancreatic ductal adenocarcinomas are inherited due to a deleterious germline mutation detected in 20% or fewer families. Pancreatic screening in high-risk individuals is proposed to allow early surgical treatment of (pre)malignant lesions. The outcomes of pancreatic surgery in high-risk individuals have never been correctly explored.

Objectives

To evaluate surgical appropriateness and search for associated factors in high-risk individuals.

Methods

A patient-level meta-analysis was performed including studies published since 1999. Individual classification distinguished the highest risk imaging abnormality into low-risk or high-risk abnormality, and the highest pathological degree of malignancy of lesions into no/low malignant potential or potentially/frankly malignant. Surgical appropriateness was considered when potentially/frankly malignant lesions were resected.

Results

Thirteen out of 24 studies were selected, which reported 90 high-risk individuals operated on. Low-risk/high-risk abnormalities were preoperatively detected in 46.7%/53.3% of operated high-risk individuals, respectively. Surgical appropriateness was consistent in 38 (42.2%) high-risk individuals, including 20 pancreatic ductal adenocarcinomas (22.2%). Identification of high-risk abnormalities was strongly associated with surgical appropriateness at multivariate analysis (P = 0.001). We proposed a score and nomogram predictive of surgical appropriateness, including high-risk abnormalities, age and existence of deleterious germline mutation.

Conclusion

Overall, 42.2% of high-risk individuals underwent appropriate surgery. The proposed score might help selecting the best candidates among high-risk individuals for pancreatic resection.

Calcium-activated chloride channel regulator 1 as a prognostic biomarker in pancreatic ductal adenocarcinoma

Background

In a previous study utilizing mass spectrometry-based proteomics, we identified calcium-activated chloride channel regulator 1 (CLCA1) as a potential tumor suppressor in pancreatic cancer and the expression was inversely correlated with patient survival. The aim of the study was to further validate the prognostic significance of CLCA1 in pancreatic cancer.

Methods

CLCA1 expression was evaluated with tissue microarrays and immunohistochemistry in 140 patients with pancreatic ductal adenocarcinoma that underwent surgical resection at Skåne University Hospital, Sweden. Kaplan-Meier and Cox proportional hazards modeling were used to explore the association between CLCA1 and clinicopathological factors and survival.

Results

CLCA1 expression was denoted as positive in 90 tumors (64.3%), with positive staining being limited to the tumor cells. There were no significant association between CLCA1 expression and established clinicopathological parameters. Low CLCA1 expression correlated significantly with shorter disease-free survival (11.9 vs 17.5 months, P = 0.042). Multivariable Cox regression analysis confirmed the results (HR 0.61, 95% CI-0.40-0.92, P = 0.019).

Conclusions

Low CLCA1 expression is an independent factor of poor disease-free survival in pancreatic cancer.

Signal-Targeted Therapies and Resistance Mechanisms in Pancreatic Cancer: Future Developments Reside in Proteomics

For patients with metastatic pancreatic cancer that are not eligible for surgery, signal-targeted therapies have so far failed to significantly improve survival. These therapeutic options have been tested in phase II/III clinical trials mostly in combination with the reference treatment gemcitabine. Innovative therapies aim to annihilate oncogenic dependency, or to normalize the tumoural stroma to allow immune cells to function and/or re-vascularisation to occur. Large scale transcriptomic and genomic analysis revealed that pancreatic cancers display great heterogeneity but failed to clearly delineate specific oncogene dependency, besides oncogenic Kras. Beyond these approaches, proteomics appears to be an appropriate approach to classify signal dependency and to identify specific alterations at the targetable level. However, due to difficulties in sampling, proteomic data for this pathology are scarce. In this review, we will discuss the current state of clinical trials for targeted therapies against pancreatic cancer. We will then highlight the most recent proteomic data for pancreatic tumours and their metastasis, which could help to identify major oncogenic signalling dependencies, as well as provide future leads to explain why pancreatic tumours are intrinsically resistant to signal-targeted therapies. We will finally discuss how studies on phosphatidylinositol-3-kinase (PI3K) signalling, as the paradigmatic pro-tumoural signal downstream of oncogenic Kras in pancreatic cancer, would benefit from exploratory proteomics to increase the efficiency of targeted therapies.

Proteomic biomarkers in body fluids associated with pancreatic cancer

Pancreatic cancer (PC) is a highly malignant disease that represents the fourth leading cancer-related death worldwide. There has been very little improvement in survival rates over recent years, and surgical resection remains the only reliable curative approach. Factors that contribute to this dismal prognosis for PC include its rapid progression and invasion, the absence of specific symptoms, and the little impact of available chemotherapy. Importantly, the management of this malignancy is also limited by the lack of highly specific and sensitive biomarkers for its diagnosis and follow-up, and their identification is therefore considered a promising strategy to improve outcomes in these patients. Numerous translational studies have explored the usefulness of body fluids as a non-invasive source of PC-specific biomarkers, and innovations in proteomic methods and technologies have provided a myriad of protein biomarkers for different cancers. The adoption of a proteomic approach has improved understanding of the biology of PC and contributed to the potential identification of protein biomarkers for this disease. This review considers the most recent research efforts to develop novel proteomic biomarkers in body fluids for PC.

Tissue and plasma proteomics for early stage cancer detection

The pursuit of novel and effective biomarkers is essential in the struggle against cancer, which is a leading cause of mortality worldwide. Here we discuss the relative advantages and disadvantages of the most frequently used proteomics techniques, concentrating on the latest advances and application of tissue and plasma proteomics for novel cancer biomarker discovery.