Neutrophil gelatinase-associated lipocalin, macrophage inhibitory cytokine 1, and carbohydrate antigen 19-9 in pancreatic juice: pathobiologic implications in diagnosing benign and malignant disease of the pancreas

Systemic Neutrophil Gelatinase-Associated Lipocalin Alterations in Chronic Pancreatitis: A Multicenter, Cross-Sectional Study

INTRODUCTION

Chronic pancreatitis (CP) is a progressive fibroinflammatory disorder lacking therapies and biomarkers. Neutrophil gelatinase-associated lipocalin (NGAL) is a proinflammatory cytokine elevated during inflammation that binds fatty acids (FAs) such as linoleic acid. We hypothesized that systemic NGAL could serve as a biomarker for CP and, with FAs, provide insights into inflammatory and metabolic alterations.

METHODS

NGAL was measured by immunoassay, and FA composition was measured by gas chromatography in plasma (n = 171) from a multicenter study, including controls (n = 50), acute and recurrent acute pancreatitis (AP/RAP) (n = 71), and CP (n = 50). Peripheral blood mononuclear cells (PBMCs) from controls (n = 16), AP/RAP (n = 17), and CP (n = 15) were measured by cytometry by time-of-flight.

RESULTS

Plasma NGAL was elevated in subjects with CP compared with controls (area under the curve [AUC] = 0.777) or AP/RAP (AUC = 0.754) in univariate and multivariate analyses with sex, age, body mass index, and smoking (control AUC = 0.874; AP/RAP AUC = 0.819). NGAL was elevated in CP and diabetes compared with CP without diabetes ( P < 0.001). NGAL + PBMC populations distinguished CP from controls (AUC = 0.950) or AP/RAP (AUC = 0.941). Linoleic acid was lower, whereas dihomo-γ-linolenic and adrenic acids were elevated in CP ( P < 0.05). Linoleic acid was elevated in CP with diabetes compared with CP subjects without diabetes ( P = 0.0471).

DISCUSSION

Elevated plasma NGAL and differences in NGAL + PBMCs indicate an immune response shift that may serve as biomarkers of CP. The potential interaction of FAs and NGAL levels provide insights into the metabolic pathophysiology and improve diagnostic classification of CP.

Neutrophil Gelatinase-Associated Lipocalin for the Differentiation of Mucinous Pancreatic Cystic Lesions

Undetermined pancreatic cystic lesion (PCL) differentiation benefits from endoscopic ultrasound (EUS) based on morphology and cyst fluid analysis, but room for new biomarkers exists. Our aim was to assess the intracystic and serum diagnostic value of neutrophil gelatinase-associated lipocalin (Ngal) and interleukin 1 beta (IL-1β) for differentiation of PCLs. This prospective study included patients from one tertiary hospital, evaluated between April 2018 and May 2020. EUS fine-needle aspiration or pancreatic pseudocysts drainage was the source of PCL intracystic liquid. The final diagnosis was based on surgery or EUS results (morphology, cytology, glucose, and CEA-carcinoembryogenic antigen). The intracystic samples were tested for Ngal, IL-1β, glucose, and CEA, and serum for Ngal and IL-1β. We evaluated 63 cysts, 33 pseudocysts, and 30 non-inflammatory cysts. The diagnostic sensitivity and specificity for mucinous PCL was 70.8% and 92.3% for intracystic Ngal (cut-off: 500-800 ng/dL), without correlation with serum Ngal, no matter the inclusion of infected pseudocysts. After exclusion of infected pseudocysts, the sensitivity and specificity for glucose were 87% and 75%, respectively, and for CEA, they were 87.1%, and 96.8%, respectively. Intracystic Ngal shows promise in differentiating mucinous PCLs, but researchers need to conduct further studies to confirm its effectiveness. Intracystic IL-1β and serum Ngal made no diagnostic contribution.

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.

Protein biomarkers in pancreatic juice and serum for identification of pancreatic cancer

BACKGROUND AND AIMS

To date, surveillance of high-risk individuals for pancreatic ductal adenocarcinoma (PDAC) has not lived up to expectations, as identification of curable stages through imaging remains challenging. Biomarkers are therefore needed. Pancreatic juice (PJ) may be a promising source, because it is in direct contact with the ductal epithelial lining from which PDAC arises. We aimed to develop a panel of biomarkers from serum and PJ to detect PDAC for future surveillance purposes.

METHODS

All patients who underwent PJ collection on secretin stimulation at the Erasmus MC were included. Both PJ and serum were evaluated. Protein levels were determined by the Lowry assay. Potential biomarkers (interleukin-8, interferon-γ, neutrophil gelatinase-associated lipocalin [NGAL], mucin 5, subtype AC [MUC5AC], mucin 2, phospholipase A2 group IB) were selected based on previously reported outcomes and assessed with enzyme-linked immunosorbent assay. Serum carbohydrate antigen 19-9 (CA19-9) values were determined by electrochemiluminescence immunoassay.

RESULTS

This study included 59 cases and 126 surveilled control subjects (who underwent PJ collection), of whom 71 had a hereditary predisposition (35 genetic, 36 familial) and 55 had (suspected neoplastic) pancreatic cysts. CA19-9 values were available for 53 cases and 48 control subjects. Serum CA19-9, as well as PJ interleukin-8, NGAL and MUC5AC, were associated with PDAC independent of age, gender, and presence of diabetes mellitus. Serum CA19-9 had a significantly higher area under the curve (AUC; .86; 95% confidence interval [CI], .79-.94) than individual PJ markers (AUC, .62-.70). A combination of PJ markers and serum CA19-9 (panel 2: sensitivity 42% [95% CI, 29-57] and specificity 96% [95% CI, 86-100]) did not improve diagnostic performance compared with CA19-9 alone (sensitivity 70% [95% CI, 56-82] and specificity 85% [95% CI, 72-94]).

CONCLUSIONS

High levels of serum CA19-9 and PJ-derived proteins are associated with PDAC. Prospective surveillance studies including individuals at risk of developing PDAC are required to validate these findings.

Diagnostic value of serum carbohydrate antigen 19-9 in pancreatic cancer: a systematic review and meta-analysis

Carbohydrate antigen 19-9 (CA19-9) is the most widely used serum biomarker for detecting pancreatic cancer (PC). Since early diagnosis is important for improving PC prognosis, a comprehensive understanding of the diagnostic performance of CA19-9 is critical. This study focused on comprehensive evaluation of the efficacy of CA19-9 in PC diagnosis. Literature research was based on the seven databases. Studies released from January 2002 to January 2022 focused on the efficacy of CA19-9 in the detection of PC were included. Summarized sensitivity, specificity, and sROC/accuracy of discrimination (AUC) were estimated. Potential publication bias was measured with Funnel plot and Egger's test. Meta-regression was performed to detect possible causes of heterogeneity. Subgroup analysis was used to assess the diagnostic efficacy of CA19-9 under different conditions. The study is registered on PROSPERO (CRD42021253861). Seventy-nine studies containing 20 991 participants who met the criteria were included. The pooled sensitivity, specificity, and AUC of CA19-9 in diagnose PC were 72% (95% CI, 71-73%), 86% (95% CI, 85-86%), and 0.8474 (95% CI, 0.8272-0.8676). Subgroup analysis suggested that the diagnostic efficiency of CA19-9 in studies with healthy controls was the highest, followed by intraductal papillary mucinous neoplasm, in pancreatitis and diabetes were consistent with the overall result. Our analysis showed that serum CA19-9 had high and stable diagnostic efficacy for PC (not affected by diabetes). Subgroup analysis showed that serum CA19-9 yielded highest effectiveness in the diagnosis of pancreatic precancerous lesions, which indicated an irreplaceable clinical value in the early detection and warning value for PC.

KRAS mutation analysis by droplet digital PCR of duodenal juice from patients with MODY8 and other pancreatic diseases

BACKGROUND

Maturity-onset diabetes of the young type 8 (MODY8 or CEL-MODY) is an inherited pancreatic disease characterized by chronic inflammation of the pancreas and diabetes. It is not known whether MODY8 patients have increased risk for developing pancreatic cancer. We investigated KRAS mutation load in duodenal juice from MODY8 patients, comparing with other groups of pancreatic disease.

METHODS

Droplet digital PCR (ddPCR) was used to detect KRAS codon 12/13/61 mutations in duodenal juice sampled from 11 MODY8 patients, nine healthy subjects and 100 patients clinically investigated due to suspected pancreatic disease.

RESULTS

KRAS mutations were detected in 4/11 patients with MODY8 (36%), 1/9 healthy subjects (11%), 15/44 patients with chronic pancreatitis (CP, 34%), 3/5 patients with pancreatic ductal adenocarcinoma (PDAC, 60%), 3/20 patients with acute pancreatitis (15%), 0/13 patients with other pancreatic disorders and 2/18 patients with nonpancreatic gastrointestinal disease (11%). Of the 28 positive juice samples, 25 (89%) had low-abundance mutations in codons 12/13, with a variant allele frequency (VAF) less than 1%. KRAS-positive patients with MODY8 or CP had significantly lower VAFs than patients with PDAC (Mann-Whitney U test; p = 0.041). Although the overall mutation detection rate was higher for subjects ≥50 years old (26%) than for younger subjects (15%), the difference was not statistically significant.

CONCLUSIONS

KRAS mutations were detectable in duodenal juice from MODY8 patients, but with low abundance and at the same frequency as in CP patients. The discriminative value of the analysis with regard to other pancreatic disease was limited.

Lipocalin-2: Structure, function, distribution and role in metabolic disorders

Lipocalin-2 (LCN-2) is a novel, 198 amino acid adipocytokine also referred to as neutrophil gelatinase-associated lipocalin (NGAL). LCN-2 is a circulatory protein responsible for the transportation of small and hydrophobic molecules (steroid, free fatty acids, prostaglandins and hormones) to target organs after binding to megalin/glycoprotein and GP330 SLC22A17 or 24p3R LCN-2 receptors. LCN-2 has been used as a biomarker for acute and chronic renal injury. It is present in a large variety of cells including neutrophil, hepatocytes, lung, bone marrow, adipose tissue, macrophages, thymus, non-neoplastic breast duct, prostate, and renal cells. Different functions have been associated with LCN-2. These functions include antibacterial, anti-inflammatory, and protection against cell and tissue stress. Moreover, LCN-2 can increase the pool of matrix metalloproteinase 9 in human neutrophil granulocytes. Other reported functions of LCN-2 include its ability to destroy the extracellular matrix, which could enable cancer progression and spread of metastasis. Recent reports show that the tissue level of LCN-2 is increased in metabolic disorders such as obesity and type 2 diabetes, suggesting an association between LCN-2 and insulin sensitivity and glucose homeostasis. The precise role of LCN-2 in the modulation of insulin sensitivity, glucose and lipid metabolism is still unclear. This review explores the structure of LCN-2, tissue distribution, and its interaction with important metabolic pathways.

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).

Review of clinical and emerging biomarkers for early diagnosis and treatment management of pancreatic cancer: towards personalised medicine

Background:

Pancreatic cancer is the 12th most commonly diagnosed cancer and the 3rd leading cause of cancer mortality and accounts for approximately 2·7% of all newly diagnosed cancer cases and 6·4% of all cancer mortalities in Canada. It has a very poor survival rate mainly due to the difficulty of detecting the disease at an early stage. Consequently, in the advancement of disease management towards the concept of precision medicine that takes individual patient variabilities into account, several investigators have focused on the identification of effective clinical biomarkers with high specificity and sensitivity, capable of early diagnosis of symptomatic patients and early detection of the disease in asymptomatic individuals at high risk for developing pancreatic cancer.

Materials and methods:

We searched several databases from August to December 2020 for relevant studies published in English between 2000 and 2020 and reporting on biomarkers for the management of pancreatic cancer. In this narrative review paper, we describe 13 clinical and emerging biomarkers for pancreatic cancers used in screening for early detection and diagnosis, to identify patients’ risk for metastatic disease and subsequent relapse, to monitor patient response to specific treatment and to provide clinicians the possibility of prospectively identifying groups of patients who will benefit from a particular treatment.

Conclusions:

Current and emerging biomarkers for pancreatic cancer with high specificity and sensitivity has the potential to account for individual patient variabilities, for early detection of disease before the onset of metastasis to improve treatment outcome and patients’ survival, help screen high-risk populations, predict prognosis, provide accurate information of patient response to specific treatment and improve patients monitoring during treatment. Thus, the future holds promise for the use of effective clinical biomarkers or a panel of biomarkers for personalised patient-specific targeted medicine for pancreatic cancer.

Biological Functions and Therapeutic Potential of Lipocalin 2 in Cancer

Lipocalin-2 (LCN2) is a secreted glycoprotein linked to several physiological roles, including transporting hydrophobic ligands across cell membranes, modulating immune responses, maintaining iron homeostasis, and promoting epithelial cell differentiation. Although LNC2 is expressed at low levels in most human tissues, it is abundant in aggressive subtypes of cancer, including breast, pancreas, thyroid, ovarian, colon, and bile duct cancers. High levels of LCN2 have been associated with increased cell proliferation, angiogenesis, cell invasion, and metastasis. Moreover, LCN2 modulates the degradation, allosteric events, and enzymatic activity of matrix metalloprotease-9, a metalloprotease that promotes tumor cell invasion and metastasis. Hence, LCN2 has emerged as a potential therapeutic target against many cancer types. This review summarizes the most relevant findings regarding the expression, biological roles, and regulation of LCN2, as well as the proteins LCN2 interacts with in cancer. We also discuss the approaches to targeting LCN2 for cancer treatment that are currently under investigation, including the use of interference RNAs, antibodies, and gene editing.

Lipocalin-2 expression and function in pancreatic diseases

Lipocalin-2 (LCN2) is a secreted molecule, expressed in various cell types, that is involved in the progression of numerous diseases and disorders. The biological functions and expression levels of LCN2 in diseases including pancreatic cancer, pancreatitis (acute and chronic), and diabetes mellitus, suggest the potential role of LCN2 as a biomarker and/or therapeutic target. However, findings on the role of LCN2 in pancreatic diseases have been contradictory. In pancreatic cancer and pancreatitis, LCN2 has been identified as a potential biomarker; increased expression levels in various biological specimens correlate with the presence of the disease and may be able to differentiate cancer and chronic pancreatitis from healthy subjects. LCN2 is also known to be an adipokine; it is upregulated in obesity and is a common co-factor in the development of pancreatic diseases. Emerging research suggests LCN2 is elevated in type 2 diabetes mellitus, but the exact role of LCN2 in this disease is not clear. In this review, we summarize research on LCN2 as it relates to pancreatic diseases, highlighting the discrepancies in the literature. By explaining and clarifying the role of LCN2 in these disorders, we aim to promote research in developing novel diagnostic and treatment strategies to reduce the burden of pancreatic diseases.

Methylated DNA in Pancreatic Juice Distinguishes Patients With Pancreatic Cancer From Controls

BACKGROUND & AIMS

Precursors of pancreatic cancer arise in the ductal epithelium; markers exfoliated into pancreatic juice might be used to detect high-grade dysplasia (HGD) and cancer. Specific methylated DNA sequences in pancreatic tissue have been associated with adenocarcinoma. We analyzed these methylated DNA markers (MDMs) in pancreatic juice samples from patients with pancreatic ductal adenocarcinomas (PDACs) or intraductal papillary mucinous neoplasms (IPMNs) with HGD (cases), and assessed their ability to discriminate these patients from individuals without dysplasia or with IPMNs with low-grade dysplasia (controls).

METHODS

We obtained pancreatic juice samples from 38 patients (35 with biopsy-proven PDAC or pancreatic cystic lesions with invasive cancer and 3 with HGD) and 73 controls (32 with normal pancreas and 41 with benign disease), collected endoscopically from the duodenum after secretin administration from February 2015 through November 2016 at 3 medical centers. Samples were analyzed for the presence of 14 MDMs (in the genes NDRG4, BMP3, TBX15, C13orf18, PRKCB, CLEC11A, CD1D, ELMO1, IGF2BP1, RYR2, ADCY1, FER1L4, EMX1, and LRRC4), by quantitative allele-specific real-time target and signal amplification. We performed area under the receiver operating characteristic curve analyses to determine the ability of each marker, and panels of markers, to distinguish patients with HGD and cancer from controls. MDMs were combined to form a panel for detection using recursive partition trees.

RESULTS

We identified a group of 3 MDMs (at C13orf18, FER1L4, and BMP3) in pancreatic juice that distinguished cases from controls with an area under the receiver operating characteristic value of 0.90 (95% CI, 0.83-0.97). Using a specificity cut-off value of 86%, this group of MDMs distinguished patients with any stage of pancreatic cancer from controls with 83% sensitivity (95% CI, 66%-93%) and identified patients with stage I or II PDAC or IPMN with HGD with 80% sensitivity (95% CI, 56%-95%).

CONCLUSIONS

We identified a group of 3 MDMs in pancreatic juice that identify patients with pancreatic cancer with an area under the receiver operating characteristic value of 0.90, including patients with early stage disease or advanced precancer. These DNA methylation patterns might be included in algorithms for early detection of pancreatic cancer, especially in high-risk cohorts. Further optimization and clinical studies are needed.

Growth differentiation factor (GDF-15) concentration combined with Ca125 levels in serum is superior to commonly used cancer biomarkers in differentiation of pancreatic mass

BACKGROUND

Pancreatic cancer (PDAC) will have been the second leading cancer-related death in the United States by 2020, according to current estimation. Its late manifestation and the lack of good early detection methods are the cause of extremely low survival rates. Therefore, there is an urgent need to develop highly sensitive and specific marker. GDF-15, a member of TGFbeta family, has recently emerged as a protein playing an important role in carcinogenesis of various neoplasms.

OBJECTIVE

Our aim was to assess the potential of GDF-15, IL-17, IL-23 serum concentration, and the panel of PDAC markers in differentiating pancreatic adenocarcinoma from chronic pancreatitis.

METHODS

Sixty-three consecutive patients operated on due to pancreatobiliary lesions were enrolled in this study. Levels of CEA, CA125 and Ca19-9 were assessed using standard laboratory protocols. A sample of serum was collected prior to the surgery via central line. Levels of GDF-15, Il-17, Il-23 were measured using a ELISA kit. After standard pathological examination of specimens obtained on surgery, patients were divided into 2 groups: 42 patients with pancreatic adenocarcinoma and 21 patients with focal chronic pancreatitis.

RESULTS

Mean GDF-15 concentration in patients with CP vs PDAC was 2247.95 (± 179.27) vs 7694.58 (± 1878.94) [pg/mL] respectively (p= 0.011). Mean concentration of Il-17, Il-23, Ca19-9, Ca125, Ca15-3, CEA in patients with CP and PDAC was 862.36 (± 30.84) vs 841.83 (± 33.94) p= 0.833; 127.85 (± 5.87) vs 127.51 (± 9.74) p= 0.175; 34.95 (± 23.34) vs 266.62 (± 49.7) p= 0.001; 13.4 (± 1.6) vs 39.27 (± 6.85) p= 0.005; 18.4 (± 1.48) vs 20.2 (± 1.38) p= 0.416; 1.96 (± 0.38) vs 5.93 (± 1.74) p= 0.004 respectively. In order to compare these markers with the routinely used ones, ROC curve was built. CA19-9 with clinically used cut-off point of ⩾ 36 IU/mL has specificity of 90.5% and sensitivity of 57.14%. At the same time GDF-15 with the optimal cut-off point of 2.7 ng/mL has specificity of 76.19% and sensitivity of 73.8%. Although in our research group CA19-9 has an excellent specificity, its usefulness is hampered by its low sensitivity. On the other hand, GDF-15 parameters are well-balanced making it a more useful biomarker of PDAC.

CONCLUSIONS

In conclusion, GDF-15 is more accurate than Ca19-9 in differentiating pancreatic mass due to chronic pancreatitis from pancreatic adenocarcinoma. Interleukin 17 and 23 cannot be considered as PDAC biomarkers. GDF-15 concentration in serum should be further investigated in order to assess their usefulness in pancreatic adenocarcinoma diagnosis.

Local and Systemic Expression of Immunomodulatory Factors in Chronic Pancreatitis

Inflammatory and fibrotic events that drive chronic pancreatitis (CP) are likely orchestrated via signaling of soluble cytokines and chemokines systemically and within the pancreas. However, a comprehensive summary of the expression of such factors during CP has not been reported to date. This information is important given continued interest in targeting cytokines that influence CP pathogenesis. Reported data on the expression change of soluble immunomodulatory factors in human CP patients were identified via a literature search using a single search term. Thirty-one articles meeting the prespecified inclusion criteria were identified to generate a compiled data summary. Compiled data demonstrated up-regulation of several factors in the blood or pancreas microenvironment of CP patients. Nine factors were elevated in both compartments, including fractalkine, IFN-γ, interleukin 1β, IL-6, IL-8, macrophage inhibitory cytokine 1, neutrophil gelatinase-associated lipocalin, transforming growth factor β, and tumor necrosis factor α. Most up-regulated factors could be classified into one of several functional groups, including inflammation, chemotaxis, angiogenesis, bone remodeling, extracellular matrix remodeling, and pain. After further validation, these factors may be used as biomarkers for disease diagnosis and identification of comorbidities, or as potential therapeutic targets.

Can NGAL be employed as prognostic and diagnostic biomarker in human cancers? A systematic review of current evidence

BACKGROUND

Some studies have reported differentially altered neutrophil gelatinase-associated lipocalin (NGAL) levels in several malignancies. We evaluated NGAL measured in plasma or urine as both prognostic and diagnostic marker for different types of human tumors.

METHODS

We performed systematic electronic searches in Medline, Embase and CRDTAS. Studies were included if they evaluated NGAL as a prognostic or diagnostic marker for human cancers. The selection of the studies, screening of the full texts and data extraction were conducted independently by 2 authors. We used the random-effects model for the meta-analyses. A methodological assessment was completed.

RESULTS

We included 35 studies dedicated to colorectal, pancreas, breast, thyroid, gastric, kidney, endometrial, brain, liver, lung, esophageal, oral and ovarian cancers. Our meta-analyses showed that, in patients with colorectal and breast cancer, positive NGAL expression was associated with a decrease of disease-free survival (hazard ratio [HR] = 2.27, 95% confidence interval [95% CI], 1.54-3.36; HR = 1.78, 95% CI, 1.33-2.38, respectively). NGAL was a negative prognostic marker of overall survival in colorectal (HR = 2.37, 95% CI, 1.68-3.34) and endometrial (HR = 4.38, 95% CI, 1.9-10.12) cancers. Discriminative power of NGAL between cancer patients and control was moderate in colorectal cancer (area under the curve [AUC] = 0.6; pooled sensitivity 0.56; pooled specificity 0.72), acceptable in pancreatic cancer (AUC = 0.8; pooled sensitivity 0.6; pooled specificity 0.8) and good in thyroid cancer (AUC = 0.9; pooled sensitivity 0.85; pooled specificity 0.96).

CONCLUSIONS

NGAL determination in plasma and urine could be useful in the prognosis of colorectal and breast cancer, but its prognostic accuracy remains uncertain for other human tumors.

A Combination of MUC5AC and CA19-9 Improves the Diagnosis of Pancreatic Cancer: A Multicenter Study

OBJECTIVES

Pancreatic cancer (PC) is a lethal malignancy that lacks specific diagnostic markers. The present study explores the diagnostic potential of the most differentially overexpressed secretory mucin MUC5AC alone and in combination with CA19-9 using multi-center training and validation sets.

METHODS

The expression of MUC5AC in benign pancreatic pathologies, PC precursor lesions, primary PC tissues and metastatic lesions was evaluated by immunohistochemistry. Circulating MUC5AC levels were measured using sandwich ELISA assay developed in-house, and CA19-9 was measured using radioimmunoassay. A combined training set (n=346) was used to evaluate the diagnostic (n=241) and predictive (n=105, total samples 201 from pre- and post-surgical and chemotherapy set) significance of MUC5AC. Results were further validated with a pre-defined cut-off value using independent sets from the Mayo Clinic (n=94) and the University of Pittsburgh Medical Center (n=321).

RESULTS

Tissue expression analyses indicated the de novo expression of MUC5AC in pancreatic intraepithelial precursor lesions 1A (PanIN1A); the expression was maintained through all stages of progression to invasive adenocarcinoma. The median circulating MUC5AC levels in patients with resectable early-stage PC (EPC) (stage 1/2; 67.2 ng/ml, IQR: 23.9-382.1) and unresectable late-stage PC (LPC) (stage 3/4; 389.7 ng/ml, IQR: 87.7-948.6) were significantly higher compared with (P-value ≤0.0001) benign controls (BC) (7.2 ng/ml, IQR: 0.4-26.5) and (P-value ≤0.0001) chronic pancreatitis (CP) controls (8.4 ng/ml, IQR: 1.5-19.2). In the diagnostic training set (n=241), MUC5AC efficiently differentiated EPC from healthy controls (HC) (83%/80% sensitive (SN)/specific (SP)), BC (67%/87% SN/SP), and CP (83%/77% SN/SP). Independent validation sets from the Mayo Clinic and UPMC confirmed the diagnostic potential of MUC5AC to differentiate EPC from BC (68%/73%; 65%/83%) and CP (68%/79%; 65%/72%). Furthermore, MUC5AC and CA19-9 combination significantly improved (p-value < 0.001) the diagnostic accuracy for differentiating resectable cases from controls.

CONCLUSIONS

MUC5AC is a valuable diagnostic biomarker, either alone or in combination with CA19-9, to differentiate PC from CP and benign controls.

Serum CA242, CA199, CA125, CEA, and TSGF are Biomarkers for the Efficacy and Prognosis of Cryoablation in Pancreatic Cancer Patients

This study aimed to compare the changes and determine the clinical significance of carbohydrate antigens CA242, CA199, CA125, carcinoembryonic antigen (CEA), and tumor-specific growth factor (TSGF) before and after cryoablation by Cryocare system. Thirty-one pancreatic cancer patients were selected to receive cryoablation by Cryocare system. The serum expression levels of CA242, CA199, CA125, CEA, and TSGF before and 1 month after treatment were determined. Meanwhile, the serum level of these factors was also determined in 31 healthy volunteers. The parameter changes were analyzed with the clinical pathological data. The serum levels of CA242, CA199, CA125, CEA, and TSGF in the pancreatic cancer group were significantly higher than those of the control group both before and after the cryoablation treatment (P < 0.05). The serum CA199, CEA, and TSGF dramatically decreased 1 month after the treatment, which were statistically different (P < 0.05). The positive rates of serum CA242, CA199, CA125, and CEA in the pancreatic cancer group were much higher than those in the control group both before and after treatment (P < 0.05), and the positive rate of TSGF was significantly higher than that of the control group before the treatment (P < 0.05). The positive rate of CA199, CEA, and TSGF after the treatment was significantly lower than that before the treatment (P < 0.05). Serum level of CA242 was correlated with the tumor diameter, clinical staging, tumor differentiation, lymph node, and liver metastasis (P < 0.05). Except gender, CA199 was correlated with all the other clinical pathological parameters (P < 0.05). The serum levels of CA125 and CEA were correlated with all the other clinical pathological parameters (P < 0.05). The serum level of TSGF was only correlated with tumor differentiation (P < 0.05). Cryoablation treatment by Cryocare system can decrease the serum levels of CA199, CEA, TSGF, and the positive rate. Serum CA199, CEA, and TSGF can be important index for pancreatic cancer treatment assessment. Serum levels of CA242, CA199, CA125, and CEA are of great clinical value for metastasis assessment and prognosis in pancreatic cancer patients.

Lipocalin 2 (LCN2) Expression in Hepatic Malfunction and Therapy

Lipocalin 2 (LCN2) is a secreted protein that belongs to the Lipocalins, a group of transporters of small lipophilic molecules such as steroids, lipopolysaccharides, iron, and fatty acids in circulation. Two decades after its discovery and after a high variety of published findings, LCN2's altered expression has been assigned to critical roles in several pathological organ conditions, including liver injury and steatosis, renal damage, brain injury, cardiomyopathies, muscle-skeletal disorders, lung infection, and cancer in several organs. The significance of this 25-kDa lipocalin molecule has been impressively increased during the last years. Data from several studies indicate the role of LCN2 in physiological conditions as well as in response to cellular stress and injury. LCN2 in the liver shows a protective role in acute and chronic injury models where its expression is highly elevated. Moreover, LCN2 expression is being considered as a potential strong biomarker for pathological conditions, including rheumatic diseases, cancer in human organs, hepatic steatosis, hepatic damage, and inflammation. In this review, we summarize experimental and clinical findings linking LCN2 to the pathogenesis of liver disease.

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.

Bile acids-mediated overexpression of MUC4 via FAK-dependent c-Jun activation in pancreatic cancer

The majority of pancreatic cancer (PC) patients are clinically presented with obstructive jaundice with elevated levels of circulatory bilirubin and alkaline phosphatases. In the current study, we examined the implications of bile acids (BA), an important component of bile, on the pathophysiology of PC and investigated their mechanistic association in tumor-promoting functions. Integration of results from PC patient samples and autochthonous mouse models showed an elevated levels of BA (p < 0.05) in serum samples compared to healthy controls. Similarly, an elevated BA levels was observed in pancreatic juice derived from PC patients (p < 0.05) than non-pancreatic non-healthy (NPNH) controls, further establishing the clinical association of BA with the pathogenesis of PC. The tumor-promoting functions of BA were established by observed transcriptional upregulation of oncogenic MUC4 expression. Luciferase reporter assay revealed distal MUC4 promoter as the primary responsive site to BA. In silico analysis recognized two c-Jun binding sites at MUC4 distal promoter, which was biochemically established using ChIP assay. Interestingly, BA treatment led to an increased transcription and activation of c-Jun in a FAK-dependent manner. Additionally, BA receptor, namely FXR, which is also upregulated at transcriptional level in PC patient samples, was demonstrated as an upstream molecule in BA-mediated FAK activation, plausibly by regulating Src activation. Altogether, these results demonstrate that elevated levels of BA increase the tumorigenic potential of PC cells by inducing FXR/FAK/c-Jun axis to upregulate MUC4 expression, which is overexpressed in pancreatic tumors and is known to be associated with progression and metastasis of PC.

Circulating microRNAs in Pancreatic Juice as Candidate Biomarkers of Pancreatic Cancer

Development of sensitive and specific biomarkers, preferably those circulating in body fluids is critical for early diagnosis of cancer. This study performed profiling of microRNAs (miRNAs) in exocrine pancreatic secretions (pancreatic juice) by microarray analysis utilizing pancreatic juice from 6 pancreatic ductal adenocarcinoma (PDAC) patients and two pooled samples from 6 non-pancreatic, non-healthy (NPNH) as controls. Differentially circulating miRNAs were subsequently validated in 88 pancreatic juice samples from 50 PDAC, 19 chronic pancreatitis (CP) patients and 19 NPNH controls. A marked difference in the profiles of four circulating miRNAs (miR-205, miR-210, miR-492, and miR-1427) was observed in pancreatic juice collected from patients with PDAC and those without pancreatic disease. Elevated levels of the four miRNAs together predicted PDAC with a specificity of 88% and sensitivity of 87%. Inclusion of serum CA19-9 level increased the sensitivity to 91% and the specificity to 100%. Enrichment of the four miRNAs in pancreatic juice was associated with decreased OS, as was the combination of miR-205 and miR-210. Higher contents of miR-205 and miR-210 were also associated with lymph node metastasis. Elevated levels of circulating miR-205, miR-210, miR-492, and miR-1247 in pancreatic juice are, therefore, promising candidate biomarkers of disease and poor prognosis in patients with PDAC.