Biomarkers for pancreatic cancer: promising new markers and options beyond CA 19-9

Development of a Fit-For-Purpose Multi-Marker Panel for Early Diagnosis of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) suffers from a lack of an effective diagnostic method, which hampers improvement in patient survival. Carbohydrate antigen 19-9 (CA19-9) is the only FDA-approved blood biomarker for PDAC, yet its clinical utility is limited due to suboptimal performance. Liquid chromatography-mass spectrometry (LC-MS) has emerged as a burgeoning technology in clinical proteomics for the discovery, verification, and validation of novel biomarkers. A plethora of protein biomarker candidates for PDAC have been identified using LC-MS, yet few has successfully transitioned into clinical practice. This translational standstill is owed partly to insufficient considerations of practical needs and perspectives of clinical implementation during biomarker development pipelines, such as demonstrating the analytical robustness of proposed biomarkers which is critical for transitioning from research-grade to clinical-grade assays. Moreover, the throughput and cost-effectiveness of proposed assays ought to be considered concomitantly from the early phases of the biomarker pipelines for enhancing widespread adoption in clinical settings. Here, we developed a fit-for-purpose multi-marker panel for PDAC diagnosis by consolidating analytically robust biomarkers as well as employing a relatively simple LC-MS protocol. In the discovery phase, we comprehensively surveyed putative PDAC biomarkers from both in-house data and prior studies. In the verification phase, we developed a multiple-reaction monitoring (MRM)-MS-based proteomic assay using surrogate peptides that passed stringent analytical validation tests. We adopted a high-throughput protocol including a short gradient (<10 min) and simple sample preparation (no depletion or enrichment steps). Additionally, we developed our assay using serum samples, which are usually the preferred biospecimen in clinical settings. We developed predictive models based on our final panel of 12 protein biomarkers combined with CA19-9, which showed improved diagnostic performance compared to using CA19-9 alone in discriminating PDAC from non-PDAC controls including healthy individuals and patients with benign pancreatic diseases. A large-scale clinical validation is underway to demonstrate the clinical validity of our novel panel.

Using microRNAs Networks to Understand Pancreatic Cancer-A Literature Review

Pancreatic cancer is a severe disease, challenging to diagnose and treat, and thereby characterized by a poor prognosis and a high mortality rate. Pancreatic ductal adenocarcinoma (PDAC) represents approximately 90% of pancreatic cancer cases, while other cases include neuroendocrine carcinoma. Despite the growing knowledge of the pathophysiology of this cancer, the mortality rate caused by it has not been effectively reduced. Recently, microRNAs have aroused great interest among scientists and clinicians, as they are negative regulators of gene expression, which participate in many processes, including those related to the development of pancreatic cancer. The aim of this review is to show how microRNAs (miRNAs) affect key signaling pathways and related cellular processes in pancreatic cancer development, progression, diagnosis and treatment. We included the results of in vitro studies, animal model of pancreatic cancer and those performed on blood, saliva and tumor tissue isolated from patients suffering from PDAC. Our investigation identified numerous dysregulated miRNAs involved in KRAS, JAK/STAT, PI3/AKT, Wnt/β-catenin and TGF-β signaling pathways participating in cell cycle control, proliferation, differentiation, apoptosis and metastasis. Moreover, some miRNAs (miRNA-23a, miRNA-24, miRNA-29c, miRNA-216a) seem to be engaged in a crosstalk between signaling pathways. Evidence concerning the utility of microRNAs in the diagnosis and therapy of this cancer is poor. Therefore, despite growing knowledge of the involvement of miRNAs in several processes associated with pancreatic cancer, we are beginning to recognize and understand their role and usefulness in clinical practice.

Neoadjuvant treatment for pancreatic cancer: Controversies and advances

Despite the advancements in the treatment of localized pancreatic cancer, several unresolved issues persist in clinical practice, especially in the neoadjuvant setting. These include determining the criteria for selecting patients for treatment, identifying the most effective chemotherapy regimens, understanding the role of radiotherapy, and accurately assessing how patients respond to treatment. Current strategies for assessing patients before surgery involve thoroughly evaluating their overall health status, analyzing tumor markers, and using advanced imaging techniques. However, existing methods for staging the disease still have limitations when it comes to accurately detecting metastatic cancer. The ongoing debate between performing surgery upfront or administering neoadjuvant therapy highlights the need for robust clinical evidence to guide treatment decisions effectively. This review analyzes the evidence regarding controversial topics in neoadjuvant pancreatic cancer treatment and discusses further research efforts to enhance patient outcomes. To improve the outcomes found with surgery alone, multimodal treatment with chemotherapy.

Autoantibodies, antigen-autoantibody complexes and antigens complement CA125 for early detection of ovarian cancer

BACKGROUND

Multiple antigens, autoantibodies (AAb), and antigen-autoantibody (Ag-AAb) complexes were compared for their ability to complement CA125 for early detection of ovarian cancer.

METHODS

Twenty six biomarkers were measured in a single panel of sera from women with early stage (I-II) ovarian cancers (n = 64), late stage (III-IV) ovarian cancers (186), benign pelvic masses (200) and from healthy controls (502), and then split randomly (50:50) into a training set to identify the most promising classifier and a validation set to compare its performance to CA125 alone.

RESULTS

Eight biomarkers detected ≥ 8% of early stage cases at 98% specificity. A four-biomarker panel including CA125, HE4, HE4 Ag-AAb and osteopontin detected 75% of early stage cancers in the validation set from among healthy controls compared to 62% with CA125 alone (p = 0.003) at 98% specificity. The same panel increased sensitivity for distinguishing early-stage ovarian cancers from benign pelvic masses by 25% (p = 0.0004) at 95% specificity. From 21 autoantibody candidates, 3 AAb (anti-p53, anti-CTAG1 and annt-Il-8) detected 22% of early stage ovarian cancers, potentially lengthening lead time prior to diagnosis.

CONCLUSION

A four biomarker panel achieved greater sensitivity at the same specificity for early detection of ovarian cancer than CA125 alone.

Growth differentiation factor-15 may be a novel biomarker in pancreatic cancer: A review

Pancreatic cancer is a highly malignant and invasive gastrointestinal tumor that is often diagnosed at an advanced stage with a poor prognosis and high mortality. Currently, carbohydrate antigen199(CA199) is the only biomarker approved by the FDA for the diagnosis of pancreatic cancer, but it has great limitations. Growth differentiation factor-15 (GDF-15) is expected to be a novel biomarker for the diagnosis, efficacy prediction, and prognosis assessment of pancreatic cancer patients. In this paper, we searched the keywords GDF-15, macrophage inhibitory cytokine-1 (MIC-1), CA199, pancreatic cancer, and tumor markers in PubMed and Web of Science, searched related articles, and read and analyzed the retrieved papers. Finally, we systematically described the characteristics, mechanism of action, and clinical value of GDF-15, aiming to provide help for the detection and treatment of pancreatic cancer.

Down regulation of Cathepsin W is associated with poor prognosis in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is associated with a very poor prognosis. Therefore, there has been a focus on identifying new biomarkers for its early diagnosis and the prediction of patient survival. Genome-wide RNA and microRNA sequencing, bioinformatics and Machine Learning approaches to identify differentially expressed genes (DEGs), followed by validation in an additional cohort of PDAC patients has been undertaken. To identify DEGs, genome RNA sequencing and clinical data from pancreatic cancer patients were extracted from The Cancer Genome Atlas Database (TCGA). We used Kaplan-Meier analysis of survival curves was used to assess prognostic biomarkers. Ensemble learning, Random Forest (RF), Max Voting, Adaboost, Gradient boosting machines (GBM), and Extreme Gradient Boosting (XGB) techniques were used, and Gradient boosting machines (GBM) were selected with 100% accuracy for analysis. Moreover, protein-protein interaction (PPI), molecular pathways, concomitant expression of DEGs, and correlations between DEGs and clinical data were analyzed. We have evaluated candidate genes, miRNAs, and a combination of these obtained from machine learning algorithms and survival analysis. The results of Machine learning identified 23 genes with negative regulation, five genes with positive regulation, seven microRNAs with negative regulation, and 20 microRNAs with positive regulation in PDAC. Key genes BMF, FRMD4A, ADAP2, PPP1R17, and CACNG3 had the highest coefficient in the advanced stages of the disease. In addition, the survival analysis showed decreased expression of hsa.miR.642a, hsa.mir.363, CD22, BTNL9, and CTSW and overexpression of hsa.miR.153.1, hsa.miR.539, hsa.miR.412 reduced survival rate. CTSW was identified as a novel genetic marker and this was validated using RT-PCR. Machine learning algorithms may be used to Identify key dysregulated genes/miRNAs involved in the disease pathogenesis can be used to detect patients in earlier stages. Our data also demonstrated the prognostic and diagnostic value of CTSW in PDAC.

The bioengineered and multifunctional nanoparticles in pancreatic cancer therapy: Bioresponisive nanostructures, phototherapy and targeted drug delivery

The multidisciplinary approaches in treatment of cancer appear to be essential in term of bringing benefits of several disciplines and their coordination in tumor elimination. Because of the biological and malignant features of cancer cells, they have ability of developing resistance to conventional therapies such as chemo- and radio-therapy. Pancreatic cancer (PC) is a malignant disease of gastrointestinal tract in which chemotherapy and radiotherapy are main tools in its treatment, and recently, nanocarriers have been emerged as promising structures in its therapy. The bioresponsive nanocarriers are able to respond to pH and redox, among others, in targeted delivery of cargo for specific treatment of PC. The loading drugs on the nanoparticles that can be synthetic or natural compounds, can help in more reduction in progression of PC through enhancing their intracellular accumulation in cancer cells. The encapsulation of genes in the nanoparticles can protect against degradation and promotes intracellular accumulation in tumor suppression. A new kind of therapy for cancer is phototherapy in which nanoparticles can stimulate both photothermal therapy and photodynamic therapy through hyperthermia and ROS overgeneration to trigger cell death in PC. Therefore, synergistic therapy of phototherapy with chemotherapy is performed in accelerating tumor suppression. One of the important functions of nanotechnology is selective targeting of PC cells in reducing side effects on normal cells. The nanostructures are capable of being surface functionalized with aptamers, proteins and antibodies to specifically target PC cells in suppressing their progression. Therefore, a specific therapy for PC is provided and future implications for diagnosis of PC is suggested.

Ultrasensitive Detection and Separation of Pancreatic Cancer Biomarker CA 19-9 Using a Multiphoton Laser Wave-Mixing Detector Interfaced to Capillary Electrophoresis

The carbohydrate antigen 19-9 (CA 19-9) is the most commonly used biomarker in the clinical diagnosis of pancreatic cancer. Multiphoton nonlinear laser wave-mixing spectroscopy is presented as an ultrasensitive detection method for CA 19-9. Wave mixing is an optical absorption-based method, and hence, one can detect CA 19-9 without labels in their native form using compact ultraviolet (UV) lasers or labeled samples using a visible laser. The wave-mixing signal exhibits a quadratic dependence on the sample concentration, and hence, it is an ideal sensor to monitor small changes in the sample. Wave mixing has inherent advantages over other absorption-based detection methods, including short optical path length (micrometer-thin samples instead of 1 cm cuvette) and excellent spatial resolution (micrometer probe). Since the laser wave-mixing probe volume is small (picoliter), it is convenient to interface to microfluidics or capillary-based electrophoresis systems to enhance chemical specificity. Our wave-mixing detectors could be configured as portable battery-powered devices suitable for field use. Laser wave-mixing spectroscopy offers enhanced selectivity levels for protein detection when coupled with capillary electrophoresis (CE). We report a concentration detection limit of 0.16 U/mL, and a corresponding mass detection limit of 1.2 × 10-8 U, and these detection limits are better than those of chemiluminescence- or ELISA- based methods.

Screening of Exosome-Derived Proteins and Their Potential as Biomarkers in Diagnostic and Prognostic for Pancreatic Cancer

In the oncological area, pancreatic cancer is one of the most lethal diseases, with 5-year survival rising just 10% in high-development countries. This disease is genetically characterized by KRAS as a driven mutation followed by SMAD4, CDKN2, and TP53-associated mutations. In clinical aspects, pancreatic cancer presents unspecific clinical symptoms with the absence of screening and early plasmatic biomarker, being that CA19-9 is the unique plasmatic biomarker having specificity and sensitivity limitations. We analyzed the plasmatic exosome proteomic profile of 23 patients with pancreatic cancer and 10 healthy controls by using Nanoscale liquid chromatography coupled to tandem mass spectrometry (NanoLC-MS/MS). The pancreatic cancer patients were subdivided into IPMN and PDAC. Our findings show 33, 34, and 7 differentially expressed proteins when comparing the IPMN vs. control, PDAC-No treatment vs. control, and PDAC-No treatment vs. IPMN groups, highlighting proteins of the complement system and coagulation, such as C3, APOB, and SERPINA. Additionally, PDAC with no treatment showed 11 differentially expressed proteins when compared to Folfirinox neoadjuvant therapy or Gemcitabine adjuvant therapy. So here, we found plasmatic exosome-derived differentially expressed proteins among cancer patients (IPMN, PDAC) when comparing with healthy controls, which could represent alternative biomarkers for diagnostic and prognostic evaluation, supporting further scientific and clinical studies on pancreatic cancer.

Progress on diagnostic and prognostic markers of pancreatic cancer

Pancreatic cancer is a malignant disease characterized by low survival and high recurrence rate, whose patients are mostly at the stage of locally advanced or metastatic disease when first diagnosed. Early diagnosis is particularly important because prognostic/predictive markers help guide optimal individualized treatment regimens. So far, CA19-9 is the only biomarker for pancreatic cancer approved by the FDA, but its effectiveness is limited by low sensitivity and specificity. With recent advances in genomics, proteomics, metabolomics, and other analytical and sequencing technologies, the rapid acquisition and screening of biomarkers is now possible. Liquid biopsy also occupies a significant place due to its unique advantages. In this review, we systematically describe and evaluate the available biomarkers that have the greatest potential as vital tools in diagnosing and treating pancreatic cancer.

Serum biomarker-based early detection of pancreatic ductal adenocarcinomas with ensemble learning

BACKGROUND

Earlier detection of pancreatic ductal adenocarcinoma (PDAC) is key to improving patient outcomes, as it is mostly detected at advanced stages which are associated with poor survival. Developing non-invasive blood tests for early detection would be an important breakthrough.

METHODS

The primary objective of the work presented here is to use a dataset that is prospectively collected, to quantify a set of cancer-associated proteins and construct multi-marker models with the capacity to predict PDAC years before diagnosis. The data used is part of a nested case-control study within the UK Collaborative Trial of Ovarian Cancer Screening and is comprised of 218 samples, collected from a total of 143 post-menopausal women who were diagnosed with pancreatic cancer within 70 months after sample collection, and 249 matched non-cancer controls. We develop a stacked ensemble modelling technique to achieve robustness in predictions and, therefore, improve performance in newly collected datasets.

RESULTS

Here we show that with ensemble learning we can predict PDAC status with an AUC of 0.91 (95% CI 0.75-1.0), sensitivity of 92% (95% CI 0.54-1.0) at 90% specificity, up to 1 year prior to diagnosis, and at an AUC of 0.85 (95% CI 0.74-0.93) up to 2 years prior to diagnosis (sensitivity of 61%, 95% CI 0.17-0.83, at 90% specificity).

CONCLUSIONS

The ensemble modelling strategy explored here outperforms considerably biomarker combinations cited in the literature. Further developments in the selection of classifiers balancing performance and heterogeneity should further enhance the predictive capacity of the method.

Exploring the potential of exosomes in diagnosis and drug delivery for pancreatic ductal adenocarcinoma

Pancreatic cancer (PC) is a cancer of the digestive system, and pancreatic ductal adenocarcinoma (PDAC) accounts for approximately 90% of all PC cases. Exosomes derived from PDAC (PDAC-exosomes) promote PDAC development and metastasis. Exosomes are nanoscale vesicles secreted by most cells, which can carry biologically active molecules and mediate communication and cargo transportation among cells. Recent studies have focused on transforming exosomes into good drug delivery systems (DDSs) to improve the clinical treatment of PDAC. This review considers PDAC as the main research object to introduce the role of PDAC-exosomes in PDAC development and metastasis. This review focuses on the following two themes: (a) the great potential of PDAC-exosomes as new diagnostic markers for PDAC, and (b) the transformation of exosomes into potential DDSs.

Laser Capture Microdissection: A Gear for Pancreatic Cancer Research

The advancement in molecular techniques has been attributed to the quality and significance of cancer research. Pancreatic cancer (PC) is one of the rare cancers with aggressive behavior and a high mortality rate. The asymptomatic nature of the disease until its advanced stage has resulted in late diagnosis as well as poor prognosis. The heterogeneous character of PC has complicated cancer development and progression studies. The analysis of bulk tissues of the disease was insufficient to understand the disease, hence, the introduction of the single-cell separating technique aided researchers to decipher more about the specific cell population of tumors. This review gives an overview of the Laser Capture Microdissection (LCM) technique, one of the single-cell separation methods used in PC research.

Clinical characteristics and outcomes in carbohydrate antigen 19-9 negative pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of death from cancer worldwide. Tumor markers like carbohydrate antigen 19-9 (CA 19-9) have been proven valuable as a diagnostic tool and a predictor for tumor staging and response to therapy.

AIM

To delineate the phenotype of normal CA 19-9 PDAC according to clinical features, disease staging and prognosis as compared with high CA 19-9 PDAC cases.

METHODS

We performed a retrospective single-center analysis of all PDAC cases admitted in our Gastroenterology department over a period of 30 mo that were diagnosed by endoscopic ultrasound-guided tissue acquisition. Patients were divided into two groups according to CA 19-9 levels over a threshold of 37 U/mL. We performed a comparison between the two groups with regard to demographic and clinical data, biomarkers, tumor staging and 6-mo survival.

RESULTS

Altogether 111 patients were recruited with 29 having documented normal CA 19-9 (< 37 U/mL). In the CA 19-9 negative group of patients, 20.68% had elevated levels of both CEA and CA 125, 13.79% for CA 125 only whilst 17.24% for CEA only. The two groups had similar demographic characteristics. Abdominal pain was more frequently reported in positive vs negative CA 19-9 PDAC cases (76.83% vs 55.17%), while smoking was slightly more prevalent in the latter group (28.04% vs 31.03%). Tumors over 2 cm were more frequently seen in the positive CA 19-9 group, reflecting a higher proportion of locally advanced and metastatic neoplasia (87.7% vs 79.3%). Six-month survival was higher for the negative CA 19-9 group (58.62% vs 47.56%).

CONCLUSION

Elevated CA 19-9 at diagnosis seems to be associated with a more pronounced symptomatology, high tumor burden and poor prognosis compared to negative CA 19-9 PDAC cases. CEA and CA 125 can be adjunctive useful markers for PDAC, especially in CA 19-9 negative cases.

Clinicopathological and Prognostic Value of Survivin Expression in Surgically Resected Pancreatic Ductal Adenocarcinoma

Background: Survival after surgery for pancreatic ductal adenocarcinoma (PDAC) remains poor. Thus, novel therapeutic concepts focus on the development of targeted therapies. In this context, inhibitor of apoptosis protein (IAP) survivin is regarded as a promising oncotherapeutic target. However, its expression and prognostic value in different tumour compartments of PDAC have not been studied. Methods: Immunohistochemical analysis of survivin in different PDAC tumour compartments from 236 consecutive patients was correlated with clinicopathological variables and survival. Results: In comparison to healthy pancreatic tissue high nuclear (p < 0.001) and high cytoplasmic (p < 0.01) survivin expression became evident in the tumour centre, along the invasion front and in lymph node metastases. Cytoplasmic overexpression of survivin in tumour centres was related to the presence of distant metastasis (p = 0.016) and UICC III/IV stages (p = 0.009), while high cytoplasmic expression at the invasion front grouped with venous infiltration (p = 0.022). Increased nuclear survivin along the invasion front correlated with perineural invasion (p = 0.035). High nuclear survivin in tumour centres represented an independent prognostic factor for overall survival of pancreatic tail carcinomas (HR 13.5 95%CI (1.4−129.7)) and correlated with a limited disease-free survival in PDAC (HR 1.80 95%CI (1.04−3.12)). Conclusion: Survivin is associated with advanced disease stages and poor prognosis. Therefore, survivin will help to identify patients with aggressive tumour phenotypes that could benefit from the inclusion in clinical trials incorporating survivin inhibitors in PDAC.

Identification and prognostic analysis of biomarkers to predict the progression of pancreatic cancer patients

BACKGROUND

Pancreatic cancer (PC) is a malignancy with a poor prognosis and high mortality. Surgical resection is the only "curative" treatment. However, only a minority of patients with PC can obtain surgery. Improving the overall survival (OS) rate of patients with PC is still a major challenge. Molecular biomarkers are a significant approach for diagnostic and predictive use in PCs. Several prediction models have been developed for patients newly diagnosed with PC that is operable or patients with advanced and metastatic PC; however, these models require further validation. Therefore, precise biomarkers are urgently required to increase the efficiency of predicting a disease-free survival (DFS), OS, and sensitivity to immunotherapy in PC patients and to improve the prognosis of PC.

METHODS

In the present study, we first evaluated the highly and selectively expressed targets in PC, using the GeoMxTM Digital Spatial Profiler (DSP) and then, we analyzed the roles of these targets in PCs using TCGA database.

RESULTS

LAMB3, FN1, KRT17, KRT19, and ANXA1 were defined as the top five upregulated targets in PC compared with paracancer. The TCGA database results confirmed the expression pattern of LAMB3, FN1, KRT17, KRT19, and ANXA1 in PCs. Significantly, LAMB3, FN1, KRT19, and ANXA1 but not KRT17 can be considered as biomarkers for survival analysis, univariate and multivariate Cox proportional hazards model, and risk model analysis. Furthermore, in combination, LAMB3, FN1, KRT19, and ANXA1 predict the DFS and, in combination, LAMB3, KRT19, and ANXA1 predict the OS. Immunotherapy is significant for PCs that are inoperable. The immune checkpoint blockade (ICB) analysis indicated that higher expressions of FN1 or ANXA1 are correlated with lower ICB response. In contrast, there are no significant differences in the ICB response between high and low expression of LAMB3 and KRT19.

CONCLUSIONS

In conclusion, LAMB3, FN1, KRT19, and ANXA1 are good predictors of PC prognosis. Furthermore, FN1 and ANXA1 can be predictors of immunotherapy in PCs.

Role of microRNAs in response to cadmium chloride in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal and aggressive malignancies with a 5-year survival rate less than 9%. Early detection is particularly difficult due to the lack of symptoms even in advanced stages. microRNAs (miRs/miRNAs) are small (~ 18-24 nucleotides), endogenous, non-coding RNAs, which are involved in the pathogenesis of several malignancies including PDAC. Alterations of miR expressions can lead to apoptosis, angiogenesis, and metastasis. The role of environmental pollutants such as cadmium (Cd) in PDAC has been suggested but not fully understood. This study underlines the role of miRs (miR-221, miR-155, miR-126) in response to cadmium chloride (CdCl2) in vitro. Lethal concentration (LC50) values for CdCl2 resulted in a toxicity series of AsPC-1 > HPNE > BxPC-3 > Panc-1 = Panc-10.5. Following the treatment with CdCl2, miR-221 and miR-155 were significantly overexpressed, whereas miR-126 was downregulated. An increase in epithelial-mesenchymal transition (EMT) via the dysregulation of mesenchymal markers such as Wnt-11, E-cadherin, Snail, and Zeb1 was also observed. Hence, this study has provided evidence to suggest that the environmental pollutant Cd can have a significant role in the development of PDAC, suggesting a significant correlation between miRs and Cd exposure during PDAC progression. Further studies are needed to investigate the precise role of miRs in PDAC progression as well as the role of Cd and other environmental pollutants.

Validation of Serum Biomarkers That Complement CA19-9 in Detecting Early Pancreatic Cancer Using Electrochemiluminescent-Based Multiplex Immunoassays

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy; its early detection is critical for improving prognosis. Electrochemiluminescent-based multiplex immunoassays were developed with high analytical performance. All proteins were analyzed in sera of patients diagnosed with PDAC (n = 138), benign pancreatic conditions (111), and healthy controls (70). The clinical performance of these markers was evaluated individually or in combination for their complementarity to CA19-9 in detecting early PDAC. Logistic regression modeling including sex and age as cofactors identified a two-marker panel of CA19-9 and CA-125 that significantly improved the performance of CA19-9 alone in discriminating PDAC (AUC: 0.857 vs. 0.766), as well as early stage PDAC (0.805 vs. 0.702) from intraductal papillary mucinous neoplasm (IPMN). At a fixed specificity of 80%, the panel significantly improved sensitivities (78% vs. 41% or 72% vs. 59%). A two-marker panel of HE4 and CEA significantly outperformed CA19-9 in separating IPMN from chronic pancreatitis (0.841 vs. 0.501). The biomarker panels evaluated by assays demonstrated potential complementarity to CA19-9 in detecting early PDAC, warranting additional clinical validation to determine their role in the early detection of pancreatic cancer.

Simple Serum Pancreatic Ductal Adenocarcinoma (PDAC) Protein Biomarkers-Is There Anything in Sight?

A poor PDAC prognosis is due to a lack of effective treatment and late diagnosis. The early detection of PDAC could significantly decrease mortality and save lives. Idealbiomarkers for PDAC should be cost-effective, detectable in easily accessible biological material, and present in sufficient concentration in the earliest possible phase of the disease. This review addresses newly selected, simple protein biomarkers—new ones such as thrombospondin-2, insulin-linked binding protein 2, lysophosphatidic acid, and autotaxin and conventional ones such as Ca19-9, inflammatory factors, and coagulation factors. Their possible use in the early detection of PDAC, differentiation from benign diseases, prognosis, and treatment response prediction is discussed. We also address the usefulness of possible combinations of biomarkers in diagnostic panels.

Pancreatitis and pancreatic cancer: A case of the chicken or the egg

Acute pancreatitis (AP), chronic pancreatitis (CP) and pancreatic cancer are three distinct pancreatic diseases with different prognoses and treatment options. However, it may be difficult to differentiate between benign and malignant disease. AP may be a first symptom of pancreatic cancer, particularly in patients between the ages of 56 and 75 with presumed idiopathic AP who had a concomitant diagnosis of new-onset diabetes mellitus or patients who present with CP at diagnosis of AP. In these patients, additional imaging is warranted, preferably by endoscopic ultrasonography. CP may lead to pancreatic cancer through oncogenic mutations, mostly in patients with hereditary CP, and in patients in whom risk factors for pancreatic cancer (e.g., nicotine and alcohol abuse) are also present. Patients with PRSS1-mediated CP and patients with a history of autosomal dominant hereditary CP without known genetic mutations may be considered for surveillance for pancreatic cancer. Pancreatic inflammation may mimic pancreatic cancer by appearing as a focal mass-forming lesion on imaging. Differentiation between the above mentioned benign and malignant disease may be facilitated by specific features like the duct-penetrating sign and the duct-to-parenchyma ratio. Research efforts are aimed towards developing a superior discriminant between pancreatitis and pancreatic cancer in the form of imaging modalities or biomarkers. This may aid clinicians in timely diagnosing pancreatic cancer in a potentially curable stage.

Current State of "Omics" Biomarkers in Pancreatic Cancer

Pancreatic cancer is one of the most fatal malignancies and the seventh leading cause of cancer-related deaths related to late diagnosis, poor survival rates, and high incidence of metastasis. Unfortunately, pancreatic cancer is predicted to become the third leading cause of cancer deaths in the future. Therefore, diagnosis at the early stages of pancreatic cancer for initial diagnosis or postoperative recurrence is a great challenge, as well as predicting prognosis precisely in the context of biomarker discovery. From the personalized medicine perspective, the lack of molecular biomarkers for patient selection confines tailored therapy options, including selecting drugs and their doses or even diet. Currently, there is no standardized pancreatic cancer screening strategy using molecular biomarkers, but CA19-9 is the most well known marker for the detection of pancreatic cancer. In contrast, recent innovations in high-throughput techniques have enabled the discovery of specific biomarkers of cancers using genomics, transcriptomics, proteomics, metabolomics, glycomics, and metagenomics. Panels combining CA19-9 with other novel biomarkers from different "omics" levels might represent an ideal strategy for the early detection of pancreatic cancer. The systems biology approach may shed a light on biomarker identification of pancreatic cancer by integrating multi-omics approaches. In this review, we provide background information on the current state of pancreatic cancer biomarkers from multi-omics stages. Furthermore, we conclude this review on how multi-omics data may reveal new biomarkers to be used for personalized medicine in the future.

Evaluation of serum ATX and LPA as potential diagnostic biomarkers in patients with pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) is a devastating disease that has a poor prognosis and a total 5-year survival rate of around 5%. The poor prognosis of PC is due in part to a lack of suitable biomarkers that can allow early diagnosis. The lysophospholipase autotaxin (ATX) and its product lysophosphatidic acid (LPA) play an essential role in disease progression in PC patients and are associated with increased morbidity in several types of cancer. In this study, we evaluated both the potential role of serum LPA and ATX as diagnostic markers in PC and their prognostic value for PC either alone or in combination with CA19-9.

METHODS

ATX, LPA and CA19-9 levels were evaluated using ELISA of serum obtained from PC patients (n = 114) healthy volunteers (HVs: n = 120) and patients with benign pancreatic diseases (BPDs: n = 94).

RESULTS

Serum levels of ATX, LPA and CA19-9 in PC patients were substantially higher than that for BPD patients or HVs (p < 0.001). The sensitivity of LPA in early phase PC was 91.74% and the specificity of ATX was 80%. The levels of ATX, LPA and CA19-9 were all substantially higher for early stage PC patients compared to levels in serum from BPD patients and HVs. The diagnostic efficacy of CA19-9 for PC was significantly enhanced by the addition of ATX and LPA (p = 0.0012).

CONCLUSION

Measurement of LPA and ATX levels together with CA19-9 levels can be used for early detection of PC and diagnosis of PC in general.

Serum Exo-EphA2 as a Potential Diagnostic Biomarker for Pancreatic Cancer

OBJECTIVES

Pancreatic cancer (PC) is a highly malignant tumor with poor detection sensitivity and specificity in biomarkers and diagnosis. Previous research indicated that serum Ephrin type-A receptor 2 in exosomes (Exo-EphA2) was highly expressed and might have facilitated cell migration in PC cells. However, the dynamics of clinical performance of serum Exo-EphA2 in PC patients are unknown. Thus, this study evaluated serum Exo-EphA2 as a potential diagnostic biomarker in PC.

METHODS

The expressions of serum Exo-EphA2 were assessed by enzyme-linked immunosorbent assay for N = 353 serum samples, including from 204 PC patients, 75 patients with benign pancreatic disease, and 74 healthy control patients. Carbohydrate antigen 19-9 (CA 19-9) and carbohydrate antigen 242 (CA 242) were measured by automated immunoassay.

RESULTS

Serum Exo-EphA2 levels were significantly higher in PC patients than in benign pancreatic disease and healthy control patients. Receiver operating characteristic curve analysis suggested that using combined diagnoses of Exo-EphA2 with CA 19-9 and CA 242 was more effective to discriminate early stage (stage I and II) in PC than in healthy controls and benign disease patients.

CONCLUSIONS

Novel findings suggest that serum Exo-EphA2 is a potential early diagnostic biomarker complementing CA 19-9 and CA 242 in PC.

A Transcriptomics-Based Meta-Analysis Combined With Machine Learning Identifies a Secretory Biomarker Panel for Diagnosis of Pancreatic Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is generally incurable due to the late diagnosis and absence of markers that are concordant with expression in several sample sources (i.e., tissue, blood, plasma) and platforms (i.e., Microarray, sequencing). We optimized meta-analysis of 19 PDAC (tissue and blood) transcriptome studies from multiple platforms. The key biomarkers for PDAC diagnosis with secretory potential were identified and validated in different cohorts. Machine learning approach i.e., support vector machine supported by leave-one-out cross-validation was used to build and test the classifier. We identified a 9-gene panel (IFI27, ITGB5, CTSD, EFNA4, GGH, PLBD1, HTATIP2, IL1R2, CTSA) that achieved ∼0.92 average sensitivity and ∼0.90 average specificity in distinguishing PDAC from healthy samples in five training sets using cross-validation. These markers were also validated in proteomics and single-cell transcriptomics studies suggesting their prognostic role in the diagnosis of PDAC. Our 9-gene classifier can not only clearly discriminate between better and poor survivors but can also precisely discriminate PDAC from chronic pancreatitis (AUC = 0.95), early stages of progression [Stage I and II (AUC = 0.82), IPMA and IPMN (AUC = 1), and IPMC (AUC = 0.81)]. The 9-gene marker outperformed the previously known markers in blood studies particularly (AUC = 0.84). The discrimination of PDAC from early precursor lesions in non-malignant tissue (AUC > 0.81) and peripheral blood (AUC > 0.80) may assist in an early diagnosis of PDAC in blood samples and thus will also facilitate risk stratification upon validation in clinical trials.

The involvement of exosomes in the diagnosis and treatment of pancreatic cancer

At the moment, pancreatic cancer is among the deadliest gastrointestinal diseases, and pancreatic cancer growth is a complex biological process that is based on different kinds of genes. Exosomes are extracellular vesicles containing microRNAs (miRNAs), messenger RNA (mRNA), and proteins, they act as the most prominent mediator of intercellular communication, and they regulate, instruct, and re-educate their surrounding microenvironment and target specific organs. Due to accumulative evidence proved that exosomes are involved in metastasis, cell proliferation, EMT, angiogenesis, and TME of pancreatic cancer, exosomes are crucial potential candidates to detect pancreatic cancer early. This review aims to convey the current understanding of the main functions employed by exosomes in early diagnosis and treatment of pancreatic cancer.

Prognostic value of lymphocyte to monocyte ratio in pancreatic cancer: a systematic review and meta-analysis including 3338 patients

Background

Recently, reports have classified lymphocyte to monocyte ratio (LMR) as an effective indicator for predicting the prognosis of pancreatic cancer. Nevertheless, the prognostic value of LMR for pancreatic cancer remains controversial. Through meta-analysis, this work intends to evaluate the potential prognostic role of pretreatment LMR in patients diagnosed with pancreatic cancer.

Methods

We reviewed and extracted eligible articles from Web of Science, PubMed, Cochrane Library, and Embase. A meta-analysis was conducted using hazard ratio (HR) and 95% confidence intervals (CIs) to assess the comparison between pretreatment LMR and overall survival (OS) and disease-free survival/recurrence-free survival/time to progression (DFS/RFS/TTP).

Results

In total, 11 studies (16 cohorts) including 3338 patients diagnosed with pancreatic cancer (PC) were enrolled in our meta-analysis. Notably, we revealed that high pretreatment LMR predicted better overall survival (OS) (HR = 0.68, 95% CI 0.58–0.80, P < 0.001, I-squared = 69.3%, Ph < 0.001) and DFS/RFS/TTP (HR = 0.55, 95% CI 0.31–0.96, P = 0.037, I-squared = 89.9%, Ph < 0.001) in patients with pancreatic cancer. Further, through subgroup analyses, we showed that high pretreatment LMR was significantly associated with the favorable OS regardless of ethnicity, study design, treatment method, variable type, the cut-off value for LMR, and disease stages of I–IV and III–IV.

Conclusion

The findings from our study suggest that high pretreatment LMR is associated with better OS and DFS/RFS/TTP in patients diagnosed with pancreatic cancer. As such, it can potentially serve as a novel prognostic biomarker for patients with pancreatic cancer.

Tumor-Suppressive miR-192-5p Has Prognostic Value in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is characterized by fast tumor progression and diagnosis at advanced, inoperable stages. Previous studies could demonstrate an involvement of miR-192-5p in epigenetic regulation of visceral carcinomas. Due to contradictory results, however, the clinical utility of miR-192-5p in PDAC has yet to be determined. MiR-192-5p expression was analyzed by RT-qRT-PCR in human PDAC and benign tissue (n = 78), blood serum (n = 81) and serum exosomes (n = 74), as well as in PDAC cell lines (n = 5), chemoresistant cell clones (n = 2), and pancreatic duct cell line H6c7. Analysis of EMT-associated (epithelial-to-mesenchymal transition) proteins was performed by immunohistochemistry and Western blot. MiR-192-5p was deregulated in PDAC as compared to healthy controls (HCs), with downregulation in macrodissected tissue (p < 0.001) and upregulation in blood serum of PDAC UICC (Union for International Cancer Control) stage IV (p = 0.016) and serum exosomes of PDAC UICC stages II to IV (p < 0.001). MiR-192-5p expression in tumor tissue was significantly lower as compared to corresponding peritumoral tissue (PDAC UICC stage II: p < 0.001; PDAC UICC stage III: p = 0.024), while EMT markers ZEB1 and ZEB2 were more frequently expressed in tumor tissue as compared to peritumoral tissue, HCs, and chronic pancreatitis. Tissue-derived (AUC of 0.86; p < 0.0001) and exosomal (AUC of 0.83; p = 0.0004) miR-192-5p could differentiate between PDAC and HCs with good accuracy. Furthermore, high expression of miR-192-5p in PDAC tissue of curatively resected PDAC patients correlated with prolonged overall and recurrence-free survival in multivariate analysis. In vitro, miR-192-5p was downregulated in gemcitabine-resistant cell clones of AsPC-1 (p = 0.029). Transient transfection of MIA PaCa-2 cells with miR-192-5p mimic resulted in downregulation of ZEB2. MiR-192-5p seems to possess a tumor-suppressive role and high potential as a diagnostic and prognostic marker in PDAC.

Single-nucleotide polymorphisms based genetic risk score in the prediction of pancreatic cancer risk

BACKGROUND

Disease-related single nucleotide polymorphisms (SNPs) based genetic risk score (GRS) has been proven to provide independent inherited risk other than family history in multiple cancer types.

AIM

To evaluate the potential of GRS in the prediction of pancreatic cancer risk.

METHODS

In this case-control study (254 cases and 1200 controls), we aimed to evaluate the association between GRS and pancreatic ductal adenocarcinoma (PDAC) risk in the Chinese population. The GRS was calculated based on the genotype information of 18 PDAC-related SNPs for each study subject (personal genotyping information of the SNPs) and was weighted by external odd ratios (ORs).

RESULTS

GRS was significantly different in cases and controls (1.96 ± 3.84 in PDACs vs 1.09 ± 0.94 in controls, P < 0.0001). Logistic regression revealed GRS to be associated with PDAC risk [OR = 1.23, 95% confidence interval (CI): 1.13-1.34, P < 0.0001]. GRS remained significantly associated with PDAC (OR = 1.36, 95%CI: 1.06-1.74, P = 0.015) after adjusting for age and sex. Further analysis revealed an association of increased risk for PDAC with higher GRS. Compared with low GRS (< 1.0), subjects with high GRS (2.0) were 99% more likely to have PDAC (OR: 1.99, 95%CI: 1.30-3.04, P = 0.002). Participants with intermediate GRS (1.0-1.9) were 39% more likely to have PDAC (OR: 1.39, 95%CI: 1.03-1.84, P = 0.031). A positive trend was observed (P trend = 0.0006).

CONCLUSION

GRS based on PDAC-associated SNPs could provide independent information on PDAC risk and may be used to predict a high risk PDAC population.

Evaluation of serum MUC5AC in combination with CA19-9 for the diagnosis of pancreatic cancer

Background

Pancreatic cancer (PC) is a highly aggressive tumor with a poor prognosis that lacks specific diagnostic markers. Mucin 5AC (MUC5AC) is a member of the mucin family, a heterogeneous group of high molecular weight, heavily glycosylated proteins that could be either membrane-bound or secreted. This multi-central study is to evaluate the performance of serum MUC5AC in combination with carbohydrate antigen 19-9 (CA19-9) for the diagnosis of PC in Asian.

Methods

Sixty-one patients with PC (comprised of early pancreatic cancer [n = 30] and late pancreatic cancer [n = 31] patients), 29 benign control, 35 choledocholithiasis, 25 chronic pancreatitis, and 34 healthy controls, were recruited from two hospitals. Serum levels of MUC5AC were evaluated by commercial ELISA kits. CA19-9 was measured by chemiluminescence immunoassay. The cutoff value of MUC5AC was determined based on optimal sensitivity and specificity.

Results

Serum MUC5AC in patients with PC (210.1 [100.5–423.8] ng/mL) presented higher levels than those in controls. The combined biomarker panel (MUC5AC and CA19-9) presented better performance and improved specificity to differentiate PC from controls (AUC 0.894; 95% CI (0.844–0.943), sensitivity 0.738, specificity 0.886) than CA19-9 (p = 0.043) or MUC5AC alone (p = 0.010); however, the latter two had no difference (p = 0.824).

Conclusions

Serum MUC5AC is a potential biomarker for PC. The combination with CA19-9 presents improved specificity and better performance.

Design of an immunohistochemistry biomarker panel for diagnosis of pancreatic adenocarcinoma

BACKGROUND

Challenges still exist in differentiating pancreatic adenocarcinoma from benign disease. The use of adjuvant testing of tissue biopsies has demonstrated potential diagnostic value. We designed a proof of concept study to first validate four individual immunohistochemistry biomarkers and then combine them into a panel to boost overall diagnostic sensitivity.

METHODS

Malignant and benign pancreas from 27 pancreaticoduodenectomy specimens underwent immunohistochemistry staining with VHL, IMP3, S100A4, S100P. Using ROC curve analysis, threshold criteria for number of cells staining were chosen for each biomarker. Biomarkers were then evaluated as a panel for their ability to discriminate malignant from benign specimens.

RESULTS

Diagnostic sensitivity of VHL, IMP3, S100A4, and S100P were 75.0%, 79.2%, 45.8%, and 0%. When VHL, IMP3, and S100A4 were grouped into a panel, they were able to distinguish cancer from normal tissue with a sensitivity of 100% and a specificity of 96%.

CONCLUSIONS

The high diagnostic value of an IHC panel consisting of VHL, IMP3, and S100A4 on surgical specimens suggests the need for future prospective studies of these biomarkers on biopsy specimens.

Circulating microRNAs as promising diagnostic biomarkers for pancreatic cancer: a systematic review

Pancreatic cancer (PC) is one of the most common forms of malignant tumors and causes of tumor-related death worldwide. The current prognosis of PC still remains poor due to the lack of effective early detection method. Recently, there is strong support that circulating miRNAs can be used as biomarkers for early detection of various cancers, including PC. The purpose of this review is to provide an overview of previous published studies on circulating miRNAs in plasma/serum for early detection of PC and summarize their diagnostic value. PubMed, Embase and Web of Science were systematically searched for eligible studies on circulating miRNAs for PC detection. Overall, 29 studies published between 2009 and 2018 evaluating 51 individual miRNAs (no P-value exceeding 0.05) and 13 miRNAs panels were included. Generally, the diagnostic performance of circulating miRNAs for PC detection was strong, with both the sensitivity and specificity of 36% individual miRNAs and 40% miRNAs panels exceeding 80%. Moreover, two promising miRNA panels were discovered and verified externally with all AUC values exceeding 0.95. Therefore, circulating miRNAs may hold potential to be used as noninvasive diagnostic biomarkers for PC, but large-scale studies are still needed to validate the promising miRNAs and optimize the miRNA panels. Since, the tremendous heterogeneity of studies in this field hampers translating miRNA markers into clinical practice, miRNA analytical procedures are also needed to be standardized in the future.

Osteopontin, Macrophage Migration Inhibitory Factor and Anti-Interleukin-8 Autoantibodies Complement CA125 for Detection of Early Stage Ovarian Cancer

Early detection of ovarian cancer promises to reduce mortality. While serum CA125 can detect more than 60% of patients with early stage (I–II) disease, greater sensitivity might be observed with a panel of biomarkers. Ten protein antigens and 12 autoantibody biomarkers were measured in sera from 76 patients with early stage (I–II), 44 patients with late stage (III–IV) ovarian cancer and 200 healthy participants in the normal risk ovarian cancer screening study. A four-biomarker panel (CA125, osteopontin (OPN), macrophage inhibitory factor (MIF), and anti-IL-8 autoantibodies) detected 82% of early stage cancers compared to 65% with CA125 alone. In early stage subjects the area under the receiver operating characteristic curve (AUC) for the panel (0.985) was significantly greater (p < 0.001) than the AUC for CA125 alone (0.885). Assaying an independent validation set of sera from 71 early stage ovarian cancer patients, 45 late stage patients and 131 healthy women, AUC in early stage disease was improved from 0.947 with CA125 alone to 0.974 with the four-biomarker panel (p = 0.015). Consequently, OPN, MIF and IL-8 autoantibodies can be used in combination with CA125 to distinguish ovarian cancer patients from healthy controls with high sensitivity. Osteopontin appears to be a robust biomarker that deserves further evaluation in combination with CA125.

Identification of Serum Biomarker Panels for the Early Detection of Pancreatic Cancer

BACKGROUND

Pancreatic cancer is a deadly disease for which available biomarkers, such as CA19-9, lack the desired sensitivity and specificity for early detection. Additional biomarkers are needed to improve both its sensitivity and specificity.

METHODS

Multiplex immunoassays were developed for selected biomarkers using a Bio-Plex 200 system, and analytical performance was optimized. All proteins were analyzed in sera of patients diagnosed with pancreatic ductal adenocarcinoma (PDAC; n = 188) or benign pancreatic conditions (131) and healthy controls (89). The clinical performance of these markers was evaluated individually or in combination for their ability to complement CA19-9 for the early detection of pancreatic cancer.

RESULTS

A 6-plex immunoassay was developed with negligible cross-reactivity, wide dynamic range, recovery of 89% to 104%, and intra-assay and interassay precision of 10.2% to 19.6% and 13.7% to 29.3%, respectively. Individually, the best biomarkers to separate PDAC early stage from chronic pancreatitis or intraductal papillary mucinous neoplasm (IPMN) were CA19-9 and MIA or CA19-9 and MIC-1. Logistic regression modeling selected the two-marker panels that significantly improved the individual biomarker performance in discriminating PDAC early stage from chronic pancreatitis (AUC_CA19-9+MIA = 0.86 vs. AUC_CA19-9 = 0.81 or AUC_MIA = 0.75 only, P < 0.05) or IPMN (AUC_CA19-9+MIC-1 = 0.81 vs. AUC_CA19-9 = 0.75 or AUC_MIC-1 = 0.73 only, P < 0.05). It was observed that osteopontin (OPN) outperformed CA19-9 in separating IPMN from chronic pancreatitis (AUC_OPN = 0.80 vs. AUC_CA19-9 = 0.70, P < 0.01).

CONCLUSIONS

The biomarker panels evaluated by assays with high analytical performance demonstrated potential complementary values to CA19-9, warranting additional clinical validation to determine their role in early detection of pancreatic cancer.

IMPACT

The validated biomarker panels could lead to earlier intervention and better outcomes.

Clinical Impact of Epithelial-to-Mesenchymal Transition Regulating MicroRNAs in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive carcinoma entities worldwide with early and rapid dissemination. Recently, we discussed the role of microRNAs as epigenetic regulators of Epithelial-to-Mesenchymal Transition (EMT) in PDAC. In this study, we investigated their value as diagnostic and prognostic markers in tissue and blood samples of 185 patients including PDAC, non-malignant pancreatic disorders, and age-matched healthy controls. Expression of the microRNA-200-family (microRNAs -141, -200a, -200b, -200c, -429) and microRNA-148a was significantly downregulated in tissue of PDAC Union internationale contre le cancer (UICC) Stage II. Correspondingly, stromal PDAC tissue showed strong expression of Fibronectin, Vimentin, and ZEB-1 (Zinc finger E-box-binding homeobox) versus low expression of E-cadherin. Transient transfection of microRNA-200b and microRNA-200c mimics resulted in the downregulation of their key target ZEB-1. Inversely, blood serum analyses of patients with PDAC UICC Stages II, III, and IV showed a significant over-expression of microRNA-200-family members, microRNA-148a, microRNA-10b, and microRNA-34a. Correspondingly, Enzyme-linked Immunosorbent Assay (ELISA) analyses revealed a significant over-expression of soluble E-cadherin in serum samples of PDAC patients versus healthy controls. The best diagnostic accuracy to distinguish between PDAC and non-PDAC in this patient collective could be achieved in tissue by microRNA-148a with an area under the receiver-operating-characteristic (ROC) curve (AUC) of 0.885 and in blood serum by a panel of microRNA-141, -200b, -200c, and CA.19-9 with an AUC of 0.890. Both diagnostic tools outreach the diagnostic performance of the currently most common diagnostic biomarker CA.19-9 (AUC of 0.834). Kaplan Meier survival analysis of this patient collective revealed an improved overall survival in PDAC patients with high expression of tissue-related microRNA-34a, -141, -200b, -200c, and -429. In conclusion, EMT-regulating microRNAs have great potential as liquid and solid biopsy markers in PDAC patients. Their prognostic and therapeutic benefits remain important tasks for future studies.

LncRNA co-expression network analysis reveals novel biomarkers for pancreatic cancer

High mortality and low survival rates for pancreatic ductal adenocarcinoma (PDAC) mainly result from the delay in diagnosis and treatment. Therefore, there is an urgent need to identify early PDAC biomarkers and new therapeutic targets. In this study, we applied a commonly used systems biology approach, the weighted gene co-expression network analysis (WGCNA), on lncRNA expression data. Eleven lncRNAs, namely A2M-AS1, DLEU2, LINC01133, LINC00675, MIR155HG, SLC25A25-AS1, LINC01857, LOC642852 (LINC00205), ITGB2-AS1, TSPOAP1-AS1 and PSMB8-AS1 have been identified and validated on an independent PDAC expression dataset. Furthermore, we characterized them by functional and pathway enrichment analysis and identified which lncRNAs showed differential expression, differential promoter methylation levels and copy number alterations between normal and PDAC samples. Finally, we also performed a survival analysis and identified A2M-AS1, LINC01133, LINC00205 and TSPOAP1-AS1 as prognostic biomarkers for PDAC. Interestingly, although only a few cancer-associated lncRNAs have been functionally characterized, LINC00675 and LINC01133 lncRNAs have already been demonstrated to be involved in PDAC development and progression. Therefore, our results provide new potential diagnostic/prognostic biomarkers and therapeutic targets for PDAC that deserve to be further investigated. Moreover, these lncRNAs may improve the understanding about molecular pathogenesis of PDAC.

Pancreatic cancer and associated exosomes

Pancreatic cancers with poor prognosis are highly malignant, readily metastatic and of immune tolerance, mainly due to delayed detection. The metastatic progression and immune tolerance of pancreatic cancer is greatly attributed to the intercellular communication. However, exosomes are deemed to be the most important tool of intercellular communicators. Thus, we present a review of pancreatic cancer and exosomes in this article. We intensively summarize the progress of early pancreatic cancer and the relationship of the proliferation, progression and metastasis of pancreatic cancer and pancreatic cancer-derived exosomes, and propose new ideas of the study of pancreatic cancer.

Systematic review on the role of serum tumor markers in the detection of recurrent pancreatic cancer

BACKGROUND

Biomarker testing can be helpful to monitor disease progression after resection of pancreatic cancer. This systematic review aims to give an overview of the literature on the diagnostic value of serum tumor markers for the detection of recurrent pancreatic cancer during follow-up.

METHODS

A systematic search was performed to 2 October 2017. All studies reporting on the diagnostic value of postoperatively measured serum biomarkers for the detection of pancreatic cancer recurrence were included. Data on diagnostic accuracy of tumor markers were extracted. Forest plots and pooled values of sensitivity and specificity were calculated.

RESULTS

Four articles described test results of CA 19-9. A pooled sensitivity and specificity of respectively 0.73 (95% CI 0.66-0.80) and 0.83 (95% CI 0.73-0.91) were calculated. One article reported on CEA, showing a sensitivity of 50% and specificity of 65%. No other serum tumor markers were discussed for surveillance purposes in the current literature.

CONCLUSION

Although testing of serum CA 19-9 has considerable limitations, CA 19-9 remains the most used serum tumor marker for surveillance after surgical resection of pancreatic cancer. Further studies are needed to assess the role of serum tumor marker testing in the detection of recurrent pancreatic cancer and to optimize surveillance strategies.

Exosomes in Pancreatic Cancer: from Early Detection to Treatment

BACKGROUND

Pancreatic cancer (PC) remains one of the most fatal forms of cancer worldwide with incidence nearly equal to mortality. This is often attributed to the fact that diagnosis is often not made until later disease stages when treatment proves difficult. Efforts have been made to reduce the mortality of PC through improvements in early screening techniques and treatments of late-stage disease. Exosomes, small extracellular vesicles involved in cellular communication, have shown promise in helping understand PC disease biology.

METHODS

In this review, we discuss current studies of the role of exosomes in PC physiology, and their potential use as diagnostic and treatment tools.

RESULTS

Exosomes have a role in diagnosing pancreatic cancer and in understanding tumor biology including migration, proliferation, chemoresistance, immunosuppression, cachexia and diabetes, and have a potential role in therapy for pancreatic cancer.

CONCLUSIONS

Exosomal analysis is beneficial in demonstrating mechanisms behind PC growth and metastasis, immunosuppression, drug resistance, and paraneoplastic conditions. Furthermore, the use of exosomes can be beneficial in detecting early-stage PC and exosomes have potential applications as therapeutic targets.

A systematic review of serum autoantibodies as biomarkers for pancreatic cancer detection

Pancreatic cancer is a leading cause of cancer-related deaths in the western world. Patients with pancreatic cancer have poor prognosis, partly due to difficulties in detecting it at early stages. While different markers have been associated with pancreatic cancer, many of them show suboptimal sensitivity and specificity. Serum autoantibodies against tumor-associated antigens have recently emerged as early stage biomarkers for different types of cancers. Given the urgent need for early and reliable biomarkers for pancreatic cancer, we undertook a systematic review of the published literature to identify primary articles that evaluated serum autoantibodies in pancreatic cancer detection by searching PubMed and ISI Web of Knowledge. Two reviewers extracted data on study characteristics and results independently. Overall, 31 studies evaluating 124 individual serum autoantibodies in pancreatic cancer detection met the inclusion criteria. In general, single autoantibody markers showed relatively low sensitivities at high specificity. A combination of markers, either multiple serum autoantibodies or serum autoantibodies combined with tumor-associated markers, led to a better diagnostic performance. However, most of the analyzed autoantibodies have only been reported in single studies and therefore need to be independently validated. We conclude that serum autoantibodies might present an option as biomarkers for early detection of pancreatic cancer, but more work is needed to identify and validate autoantibody signatures that are associated with early stage pancreatic cancer.

Preoperative Carbohydrate Antigen 19-9: Its Neglected Role in Alpha-Fetoprotein-Negative Hepatocellular Carcinoma Patients

PURPOSE

The study aimed to investigate the prognostic role of the preoperative carbohydrate antigen 19-9 (CA19-9) level in alpha-fetoprotein (AFP)-negative (AFP < 25 ng/ml) hepatocellular carcinoma (HCC) patients.

METHODS

From December 2004 to December 2013, 750 patients diagnosed with AFP-negative HCC following curative resection were enrolled. Both univariate and multivariate analyses were performed to clarify the prognostic factors for overall survival (OS) and disease-free survival (DFS).

RESULTS

The optimal cutoff point for preoperative CA19-9 was 32.6 U/ml, and the value of the area under the curve was 0.640. The 1-, 3-, and 5-year OS rates were 88.4, 72.2, and 57.0%, respectively, for the CA19-9 > 32.6 U/ml group and 97.0, 83.3, and 79.9%, respectively, for the CA19-9 ≤ 32.6 U/ml group (P < 0.001). The 1-, 3-, and 5-year DFS rates were 71.8, 47.7, and 34.8%, respectively, for the CA19-9 > 32.6 U/ml group and 80.8, 63.6, and 55.5%, respectively, for the CA19-9 ≤ 32.6 U/ml group (P < 0.001). The multivariate analysis showed that CA19-9 > 32.6 U/ml was one of the most significant unfavorable predictors of OS and DFS (P < 0.001 for both).

CONCLUSIONS

Preoperative CA19-9 > 32.6 U/ml is a predictor of dismal prognosis and can be employed as a prognostic marker for patient selection in AFP-negative HCC management.

Prognostic Value of Preoperative Serum Carcinoembryonic Antigen and Carbohydrate Antigen 19-9 After Resection of Ampullary Cancer

BACKGROUND

The purpose of this study is to investigate the prognostic value of pre-resection serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 after resection of ampullary cancer (AC) in consideration of intestinal (IT) and pancreatobiliary (PT) subtypes.

METHODS

Overall survival (OS) analysis of patients undergoing curative resection of ampullary cancer.

RESULTS

Elevated preoperative CEA (P = 0.013) and CA 19-9 levels (P = 0.030) were significant prognostic factors. Subgroup analysis, however, showed both markers having prognostic value only for the IT subgroup. Pre-resection CEA within normal range identified a subgroup of IT patients with an excellent median survival of 145 months. Compared to other AC patients, this low-risk IT_CEA^- subpopulation was characterized by less frequent advanced pT stages (pT3/pT4, 41 vs. 62%; P = 0.047) and lymph node involvement (pN+, 30 vs. 65%; P = 0.001). OS of this subgroup was significantly better compared to other AC patients (145 vs. 25 months; HR = 3.8; P < 0.001). By multivariate survival analysis, the patient age, the PT subtype, and an elevated pre-resection serum CEA value were identified as independent prognostic variables.

CONCLUSIONS

In AC, the histomorphologic subclassification is highly relevant regarding the prognostic value of preoperative serum CEA and CA 19-9. IT-patients with normal preoperative CEA represent a favorable subgroup with excellent long-term survival.

Comparison of the tumor cell secretome and patient sera for an accurate serum-based diagnosis of pancreatic ductal adenocarcinoma

Pancreatic cancer is the currently most lethal malignancy. Toward an accurate diagnosis of the disease in body liquids, we studied the protein composition of the secretomes of 16 primary and established cell lines of pancreatic ductal adenocarcinoma (PDAC). Compared to the secretome of non-tumorous cells, 112 proteins exhibited significantly different abundances. Functionally, the proteins were associated with PDAC features, such as decreased apoptosis, better cell survival and immune cell regulation. The result was compared to profiles obtained from 164 serum samples from two independent cohorts - a training and a test set - of patients with PDAC or chronic pancreatitis and healthy donors. Eight of the 112 secretome proteins exhibited similar variations in their abundance in the serum profile specific for PDAC patients, which was composed of altogether 189 proteins. The 8 markers shared by secretome and serum yielded a 95.1% accuracy of distinguishing PDAC from healthy in a Receiver Operating Characteristic curve analysis, while any number of serum-only markers produced substantially less accurate results. Utility of the identified markers was confirmed by classical enzyme linked immunosorbent assays (ELISAs). The study highlights the value of cell secretome analysis as a means of defining reliable serum biomarkers.

Upregulated exosomic miR‑23b‑3p plays regulatory roles in the progression of pancreatic cancer

Pancreatic cancer (PC) is one of the most lethal malignances. Identification of biomarkers for early diagnosis of PC is a key imperative. MicroRNAs (miRNAs) have been shown to be valuable biomarkers in the context of several cancers. Exosomes refer to vesicles released by the tumor cells at the early stage of disease. Thus, detection of miRNA in exosomes can be used as a potential biomarker for PC. In this study, we profiled serum levels of miRNAs in patients with chronic pancreatitis (CP) and PC; the role of miR-23b-3p in PC progression was assessed in vitro. Additionally, we assessed, the expression of miR-23b-3p in exosomes isolated from serum samples and assessed the correlation between the expression of miR-23b-3p and carbohydrate antigen 19-9 (CA19-9). Three serum samples each were randomly selected from healthy controls (n=20), and patients with CP (n=18) and PC (n=16) for miRNA microarray profiling. The dysregulated miRNAs were confirmed using qRT-PCR. Four dysregulated miRNAs common to patients with CP and PC were identified on miRNA microarray analysis and confirmed by qRT-PCR. miR-23b-3p level was consistently higher in serum samples from PC patients as compared to those from healthy controls and CP patients (p<0.05). Overexpression of miR-23b-3p promoted proliferation, migration, and invasion capability of PC cells in vitro (p<0.05). Furthermore, miR-23b-3p was upregulated in exosomes of PC serum samples and the supernatant of pancreatic cancer cells (PANC-1), and the expression levels of miR-23b-3p were associated with those of serum CA19-9 levels. This study provides insights into the potential role of miR-23b-3p as a novel biomarker and target for treatment of PC.

Drug-eluting scaffold inhibited in vivo pancreatic tumorigenesis by engaging murine CCR4+CD8+ T cells

CCL17 is well known for its ability to engage CCR4⁺CD8⁺ T cells, which have been shown to play a critical role in preventing tumorigenesis. In this study, we attempted to inhibit in vivo pancreatic tumorigenesis by engaging murine CCR4⁺CD8⁺ T cells through a drug-eluting scaffold with a payload of CCL17. The drug-eluting scaffold was fabricated by electrospinning polyglyconate and porcine gelatin. The electrospun scaffold featured randomly distributed non-woven fibers with diameters ranging from 1μm to 4μm. The in vitro study confirmed that scaffolding materials were non-cytotoxic to pancreatic cancer cells. The in vivo study showed an increased presence of murine CCR4⁺CD8⁺ T cells into the tumor mass treated with drug-eluting scaffold compared to those with non-eluting scaffold or the control groups. The weights of tumor masses were 132.04mg±12.25mg in the control group, 158.12mg±18.98mg in the NES group and 96.22mg±14.56mg in the DES group, respectively. The volumes of tumor masses were 1035.21mm³±128.97mm³ in the control group, 978.56mm³±110.19mm³ in the NES group and 634.35mm³±87.12mm³ in the DES group, respectively. Further study showed that the increased presence of CCR4⁺CD8⁺ T cells also inhibited the hepatic metastasis of pancreatic cancer cells. Our study shed a new light on the post-operative treatment of pancreatic cancer to prevent the recurrence.

Murine and human pancreatic tumor exosome recovery in mouse serum: Diagnostic and prognostic potential and target cell delivery

Exosomes (Exo), powerful intercellular communicators, are recovered in all body fluids, suggesting suitability for diagnosis and prognosis. Easy in vitro manipulation recommends Exo as drug vehicles. Aiming to consolidate diagnostic and therapeutic potential of Exo, we evaluated recovery and fate of tumor (TEX) and exogenous Exo in syngeneic and xenogeneic mice bearing a murine or a human pancreatic adenocarcinoma. A significant increase in serum (S)-TEX was observed 2 weeks after tumor cell application. Instead, S-TEX declined within 3-6 days after tumor excision. Intravenously injected dye-labeled TEX were rapidly cleared from the serum. Partly being degraded in the liver, the majority is taken-up by PBL, liver, bone marrow and lung cells. In the tumor-bearing host TEX persisted longer becoming enriched in tumor cells and metastatic organs. Accordingly, an antibody blockade of a TEX marker hampered disseminated tumor cell settlement in selected organs. In brief, a tumor marker panel appears suited for S-TEX recovery. In murine models, S-TEX are qualified for therapy control and follow-up studies. Despite rapid clearance from the serum, Exo uptake by host cells is most promising for tailored Exo as drug transporter.