NPTX2 hypermethylation in pure pancreatic juice predicts pancreatic neoplasms. Am J Med Sci. 2013;346:175-180. [PMID: 23360791 DOI: 10.1097/maj.0b013e31827b94b6]

Systematic review and meta-analysis: Diagnostic performance of DNA alterations in pancreatic juice for the detection of pancreatic cancer

BACKGROUND AND AIMS

Pancreatic cancer has a dismal prognosis. So far, imaging has been proven incapable of establishing an early enough diagnosis. Thus, biomarkers are urgently needed for early detection and improved survival. Our aim was to evaluate the pooled diagnostic performance of DNA alterations in pancreatic juice.

METHODS

A systematic literature search was performed in EMBASE, MEDLINE Ovid, Cochrane CENTRAL and Web of Science for studies concerning the diagnostic performance of DNA alterations in pancreatic juice to differentiate patients with high-grade dysplasia or pancreatic cancer from controls. Study quality was assessed using QUADAS-2. The pooled prevalence, sensitivity, specificity and diagnostic odds ratio were calculated.

RESULTS

Studies mostly concerned cell-free DNA mutations (32 studies: 939 cases, 1678 controls) and methylation patterns (14 studies: 579 cases, 467 controls). KRAS, TP53, CDKN2A, GNAS and SMAD4 mutations were evaluated most. Of these, TP53 had the highest diagnostic performance with a pooled sensitivity of 42% (95% CI: 31-54%), specificity of 98% (95%-CI: 92%-100%) and diagnostic odds ratio of 36 (95% CI: 9-133). Of DNA methylation patterns, hypermethylation of CDKN2A, NPTX2 and ppENK were studied most. Hypermethylation of NPTX2 performed best with a sensitivity of 39-70% and specificity of 94-100% for distinguishing pancreatic cancer from controls.

CONCLUSIONS

This meta-analysis shows that, in pancreatic juice, the presence of distinct DNA mutations (TP53, SMAD4 or CDKN2A) and NPTX2 hypermethylation have a high specificity (close to 100%) for the presence of high-grade dysplasia or pancreatic cancer. However, the sensitivity of these DNA alterations is poor to moderate, yet may increase if they are combined in a panel.

Diagnostic value of neuronal pentraxin II methylation in patients with pancreatic cancer: Meta-analysis

BACKGROUND

Pancreatic cancer (PC) is a devasting disease of which mortality almost parallels its incidence. PC tissue may express aberrantly methylated neuronal pentraxin II (NPTX2), but it is unclear what the consequences of this are.

METHODS

We systematically searched PubMed, Web of Science, the Chinese National Knowledge Infrastructure (CNKI), from inception to July 15, 2020, to identify if the detection of methylated NPTX2 have sufficient sensitivity and specificity to identify PC from other benign pancreatic diseases.

RESULTS

Majority of the studies obtained samples from pancreatic juice by endoscopy or surgery and composed of population with chronic pancreatitis, benign cystic lesion, intraductal papillary mucinous neoplasm, and healthy controls. Our results demonstrated that the diagnostic value of methylated NPTX2 is of widely various sensitivity and specificity and it shown higher specificity in differentiate PC from benign diseases. The lab method of quantitative real-time methylation-specific PCR (QMSP) has higher specificity than real-time methylation-specific PCR (MSP) in detecting the indicator.

CONCLUSIONS

NPTX2 methylation could serve as a promising molecular biomarker for pancreatic cancer diagnosis, for its high diagnostic value in differentiating pancreatic cancer from benign pancreatic disease with the lab method. The variable sensitivity of methylated NPTX2 was multifactorial, and it must be promoted before applied as screening test in clinical practice. Furthermore, experiments on methylated NPTX2 were needed to expanded for lower the heterogeneity.

Overexpression of NPTX2 Promotes Malignant Phenotype of Epithelial Ovarian Carcinoma via IL6-JAK2/STAT3 Signaling Pathway Under Hypoxia

Background

Epithelial ovarian cancer (EOC) is the main subtype of ovarian cancer and shows an aggressive phenotype and poor prognosis. Neuronal pentraxin II (NPTX2) is a member of the neuronal pentraxin family and plays a contradictory role in different tumors. However, there has been no report about the possible role and effect of NPTX2 in EOC.

Methods

Bioinformatics analysis, qPCR, western blotting and immunohistochemistry were used to detect the expression of NPTX2 in EOC. Lentivirus-based transfection for NPTX2 overexpression or knockdown was performed on the EOC cell lines A2780, HEY, SKOV3 and OVCAR-3. The effect of NPTX2 on the malignant phenotype of EOC was examined through methods of MTS assay, Edu assay, transwell assay, western blotting analysis, qPCR analysis, luciferase reporter assay and xenograft experiment.

Results

EOC tissues showed higher NPTX2 expression than the normal tissues with poor prognosis. NPTX2 overexpression can promote the proliferation, invasion, migration and tumorigenesis of EOC via IL6-JAK2/STAT3 signaling pathway. Moreover, hypoxia-inducible factor-1(HIF-1) can promote the transcription and expression of NPTX2 under the hypoxic environment. NPTX2 knockdown abolished the hypoxia-induced malignant phenotypes in ECO.

Conclusions

The above results suggest that NPTX2 may play a novel role in ovarian cancer's malignant phenotype and act as a promising treatment target for EOC molecular therapy.

Clinical Applications of Circulating Tumour DNA in Pancreatic Adenocarcinoma

Pancreatic adenocarcinoma remains one of the most aggressive cancers with an ongoing dismal survival rate despite some recent advances in treatment options. This is largely due to the typically late presentation and limited effective therapeutic options in advanced disease. There are numerous circulating biomarkers that have potential clinical application as tumour markers, including circulating tumour DNA (ctDNA), circulating tumour cells (CTCs), cell-free RNA (cfRNA), exosomes and circulating tumour proteins. This review will focus on the development of ctDNA as a non-invasive liquid biopsy, with its high sensitivity and specificity having potential clinical applications in pancreatic cancer. These include a role in screening, prognostication via the detection of minimal residual disease, early detection of recurrence, and for patients with advanced disease; tumour genotyping and monitoring treatment response. Prospective randomised adjuvant clinical trials are currently underway, exploring the impact of ctDNA-guided adjuvant therapy decisions. In this review, we provide perspectives on the current literature and considerations of future directions.

Analysis of DNA Hypermethylation in Pancreatic Cancer Using Methylation-Specific PCR and Bisulfite Sequencing

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive tumor and the fourth common cause of cancer death in the Western world. The lack of effective therapeutic strategies is attributed to the late diagnosis of this disease. Methylation markers could improve early detection and help in the surveillance of PDAC after treatment. Analysis of hypermethylation in the tumor tissue and tumor-derived exosomes might help to identify new therapeutic strategies and aid in the understanding of the pathophysiological changes occurring in pancreatic cancer. There are several methods for the detection of methylation events. Whereas methylation-specific PCR (MSP-PCR) is the method of choice, the cost reductions in DNA sequencing enables researchers to add bisulfite sequencing (BSS) to their repertoire if a small number of genes will be tested in a larger set of patients' samples. During the last years, several techniques to isolate and analyze DNA methylation have been proposed, but DNA modification using sodium bisulfite is still the gold standard.

Liquid biopsies for management of pancreatic cancer

Pancreatic cancer is one of the main causes of cancer-related deaths worldwide. It is asymptomatic at an early stage, and most diagnosis occurs when the disease is already at a late stage, by which time the tumor is nonresectable. In order to increase the overall survival of patients with pancreatic cancer, as well as to decrease the cancer burden, it is necessary to perform early diagnosis, prognosis stratifications and cancer monitoring using accurate, minimally invasive, and cost-effective methods. Liquid biopsies seek to detect tumor-associated biomarkers in a variety of extractable body fluids and can help to monitor treatment response and disease progression, and even predict patient outcome. In patients with pancreatic cancer, tumor-derived materials, primarily circulating tumor DNA, circulating tumor cells and exosomes, are being studied for inclusion in the management of the disease. This review focuses on describing the biology of these biomarkers, methods for their enrichment and detection, as well as their potential for clinical application. Moreover, we discuss the future direction of liquid biopsies and introduce how they can be exploited toward point of care personalized medicine for the management of pancreatic cancer.

Cell-free DNA promoter hypermethylation in plasma as a predictive marker for survival of patients with pancreatic adenocarcinoma

Introduction

Few prognostic biomarkers are available for pancreatic cancer. The aim of this study is to examine the correlation between the survival of pancreatic adenocarcinoma patients and hypermethylated genes in plasma-derived cell-free DNA.

Methods

Consecutive patients with pancreatic adenocarcinoma were prospectively included and staged according to the TNM classification. Methylation-specific PCR of 28 genes was conducted. A survival prediction model independent of cancer stage and stage-specific survival prediction models were developed by multivariable Cox regression analysis using backward stepwise selection.

Results

Ninety-five patients with pancreatic adenocarcinoma were included. Patients with more than 10 hypermethylated genes had a HR of 2.03 (95% CI; 1.15-3.57) compared to patients with fewer hypermethylated genes. Three survival prediction models were developed: Total group; (American Society of Anesthesiologists score (ASA)=3, GSTP1, SFRP2, BNC1, SFRP1, TFPI2, and WNT5A) Risk groups 2, 3 and 4 had a HR of 2.65 (95% CI; 1.24-5.66), 4.34 (95% CI; 1.98-9.51) and 21.19 (95% CI; 8.61-52.15), respectively, compared to risk group 1. Stage I-II; (ASA=3, SFRP2, and MESTv2) Risk groups 2, 3 and 4 had a HR of 4.83 (95% CI; 2.01-11.57), 9.12 (95% CI; 2.18-38.25) and 70.90 (95% CI; 12.63-397.96), respectively, compared to risk group 1. Stage IV; (BMP3, NPTX2, SFRP1, and MGMT) Risk group 2 had a HR of 5.23 (95% CI; 2.13-12.82) compared to risk group 1.

Conclusion

Prediction models based on cell-free DNA hypermethylation stratified pancreatic adenocarcinoma patients into risk groups according to survival. The models have the potential to work as prognostic biomarkers. However, further validation of the results is required to substantiate the findings.

Endoscopic Pancreas Fluid Collection: Methods and Relevance for Clinical Care and Translational Science

Pancreatic secretions have an important role in the regulation of a normal nutritional state but can be altered owing to a variety of pathophysiological mechanisms in the context of exocrine pancreatic disease. The development of an endoscopic technique for collection of pancreatic fluid, termed endoscopic pancreatic function testing, has led to improved understanding of these alterations and is particularly helpful to characterize chronic pancreatitis. In addition, investigators have found endoscopically collected pancreatic fluid to be a valuable biofluid for the purposes of translational science. Techniques such as proteomic, cytokine, genetic mutation, DNA methylation, and microRNA analyses, among others, can be utilized to gain a better understanding of the molecular characteristics of chronic pancreatitis and other pancreatic diseases. Endoscopic collection of pancreatic fluid is safe and relatively straightforward, permitting opportunities for longitudinal analysis of these translational markers throughout the course of disease. This manuscript summarizes our current knowledge of pancreatic fluid, with an emphasis on proper techniques for sample collection and handling, its clinical utility, and preliminary observations in translational science.

The need for effective pancreatic cancer detection and management: a biomarker-based strategy

Pancreatic cancer (Pa) is generally a very aggressive disease, with few effective approaches available for early diagnosis or therapy. These factors, combined with the aggressiveness and chemoresistance of Pa, results in a bleak outcome post-diagnosis. Cancer-related biomarkers have established capabilities for diagnosis, prognosis and screening and can be exploited to aid in earlier less-invasive diagnosis and optimization of targeted therapies. Pa has only one US FDA-approved biomarker, CA19-9, which has significant limitations. Hence, it is vital that novel biomarkers are identified and validated to diagnose, treat, control and monitor Pa. This review focuses on existing and potential Pa-associated markers and discusses how they may be applied in cohort for improved management of Pa.

Evaluation of DNA methylation markers and their potential to predict human aging

We present epigenetic methylation data for two genetic loci, GRIA2, and NPTX2, which were tested for prediction of age from different donors of biofluids. We analyzed 44 saliva samples and 23 blood samples from volunteers with ages ranging from 5 to 72 years. DNA was extracted and bisulfite modified using commercial kits. Specific primers were used for amplification and methylation profiles were determined by pyrosequencing. Methylation data from both markers and their relationship with age were determined using linear regression analysis, which indicates a positive correlation between methylation and age. Older individuals tend to have increased methylation in both markers compared to younger individuals and this trend was more pronounced in the GRIA2 locus when compared to NPTX2. The epigenetic predicted age, calculated using a GRIA2 regression analysis model, was strongly correlated to chronological age (R(2) = 0.801), with an average difference of 6.9 years between estimated and observed ages. When using a NPTX2 regression model, we observed a lower correlation between predicted and chronological age (R(2) = 0.654), with an average difference of 9.2 years. These data indicate these loci can be used as a novel tool for age prediction with potential applications in many areas, including clinical and forensic investigations.

Analysis of DNA methylation in pancreatic cancer: an update

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive tumor and the fourth common cause of cancer death in the Western world. The lack of effective therapeutic strategies is due to the late diagnosis of this disease. Methylation markers could improve early detection and help in the surveillance of PDAC after treatment. Analysis of hypermethylation in the tumor tissue might help to identify new therapeutic strategies and aid in the understanding of the pathophysiological changes occurring in pancreatic cancer. There are several methods for the detection of methylated events, but methylation-specific PCR (MSP-PCR) is the method of choice if a small number of genes will be tested in a larger set of patients samples. After isolation of the DNA by standard procedure, the DNA is then modified using sodium bisulfide.

Genomics of pancreatic ductal adenocarcinoma

Pancreatic cancer is one of the worst prognostic cancers because of the late diagnosis and the absence of effective treatment. Within all subtypes of this disease, ductal adenocarcinoma has the shortest survival time. In recent years, global genomics profiling allowed the identification of hundreds of genes that are perturbed in pancreatic cancer. The integration of different omics sources in the study of pancreatic cancer has revealed several molecular mechanisms, indicating the complex history of its development. However, validation of these genes as biomarkers for early diagnosis, prognosis or treatment efficacy is still incomplete but should lead to new approaches for the treatment of the disease in the future.

Epigenetics and pancreatic cancer: Pathophysiology and novel treatment aspects

An improvement in pancreatic cancer treatment represents an urgent medical goal. Late diagnosis and high intrinsic resistance to conventional chemotherapy has led to a dismal overall prognosis that has remained unchanged during the past decades. Increasing knowledge about the molecular pathogenesis of the disease has shown that genetic alterations, such as mutations of K-ras, and especially epigenetic dysregulation of tumor-associated genes, such as silencing of the tumor suppressor p16^ink4a, are hallmarks of pancreatic cancer. Here, we describe genes that are commonly affected by epigenetic dysregulation in pancreatic cancer via DNA methylation, histone acetylation or miRNA (microRNA) expression, and review the implications on pancreatic cancer biology such as epithelial-mesenchymal transition, morphological pattern formation, or cancer stem cell regulation during carcinogenesis from PanIN (pancreatic intraepithelial lesions) to invasive cancer and resistance development. Epigenetic drugs, such as DNA methyltransferases or histone deactylase inhibitors, have shown promising preclinical results in pancreatic cancer and are currently in early phases of clinical development. Combinations of epigenetic drugs with established cytotoxic drugs or targeted therapies are promising approaches to improve the poor response and survival rate of pancreatic cancer patients.

Diagnosis of pancreatic neoplasms using a novel method of DNA methylation analysis of mucin expression in pancreatic juice

Mucins (MUC) play crucial roles in carcinogenesis and tumor invasion in pancreatic ductal adenocarcinoma (PDAC) and intraductal papillary mucinous neoplasms (IPMNs). Our immunohistochemistry (IHC) studies have shown a consensus position on mucin expression profiles in pancreatic neoplasms as follows: MUC1-positive but MUC2-negative expression in PDACs; MUC1-negative but MUC2-positive expression in intestinal-type IPMNs (dangerous type); MUC1-negative and MUC2-negative expression in gastric-type IPMNs (safe type); High MUC4 expression in PDAC patients with a poor outcome; and MUC4-positive expression in intestinal-type IPMNs. We also showed that three mucin genes (MUC1, MUC2 and MUC4) expression in cancer cell line was regulated by DNA methylation. We have developed a novel 'methylation-specific electrophoresis (MSE)' method to analyze the DNA methylation status of mucin genes by high sensitivity and resolution. By using the MSE method, we evaluated pancreatic juice samples from 45 patients with various pancreatic lesions. The results were compared with final diagnosis of the pancreatic lesions including IHC of mucin expression in the paired pancreatic tissues. The results indicated that the DNA methylation status of MUC1, MUC2 and MUC4 in pancreatic juice matched with the mucin expression in tissue. Analyses of the DNA methylation status of MUC1, MUC2 and MUC4 were useful for differential diagnosis of human pancreatic neoplasms, with specificity and sensitivity of 87% and 80% for PDAC; 100% and 88% for intestinal-type IPMN; and 88% and 77% for gastric-type IPMN, respectively. In conclusion, MSE analysis of human pancreatic juice may provide useful information for selection of treatment for pancreatic neoplasms.