Detection of serum MMP-7 and MMP-9 in cholangiocarcinoma patients: evaluation of diagnostic accuracy

Recent Advancement in Diagnosis of Biliary Tract Cancer through Pathological and Molecular Classifications

Biliary tract cancers (BTCs), including intrahepatic, perihilar, and distal cholangiocarcinomas, as well as gallbladder cancer, are a diverse group of cancers that exhibit unique molecular characteristics in each of their anatomic and pathological subtypes. The pathological classification of BTCs compromises distinct growth patterns, including mass forming, periductal infiltrating, and intraductal growing types, which can be identified through gross examination. The small-duct and large-duct types of intrahepatic cholangiocarcinoma have been recently introduced into the WHO classification. The presentation of typical clinical symptoms, as well as the extensive utilization of radiological, endoscopic, and molecular diagnostic methods, is thoroughly detailed in the description. To overcome the limitations of traditional tissue acquisition methods, new diagnostic modalities are being explored. The treatment landscape is also rapidly evolving owing to the emergence of distinct subgroups with unique molecular alterations and corresponding targeted therapies. Furthermore, we emphasize the crucial aspects of diagnosing BTC in practical clinical settings.

Identification of a novel bile marker clusterin and a public online prediction platform based on deep learning for cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is a highly aggressive malignant tumor, and its diagnosis is still a challenge. This study aimed to identify a novel bile marker for CCA diagnosis based on proteomics and establish a diagnostic model with deep learning.

METHODS

A total of 644 subjects (236 CCA and 408 non-CCA) from two independent centers were divided into discovery, cross-validation, and external validation sets for the study. Candidate bile markers were identified by three proteomics data and validated on 635 clinical humoral specimens and 121 tissue specimens. A diagnostic multi-analyte model containing bile and serum biomarkers was established in cross-validation set by deep learning and validated in an independent external cohort.

RESULTS

The results of proteomics analysis and clinical specimen verification showed that bile clusterin (CLU) was significantly higher in CCA body fluids. Based on 376 subjects in the cross-validation set, ROC analysis indicated that bile CLU had a satisfactory diagnostic power (AUC: 0.852, sensitivity: 73.6%, specificity: 90.1%). Building on bile CLU and 63 serum markers, deep learning established a diagnostic model incorporating seven factors (CLU, CA19-9, IBIL, GGT, LDL-C, TG, and TBA), which showed a high diagnostic utility (AUC: 0.947, sensitivity: 90.3%, specificity: 84.9%). External validation in an independent cohort (n = 259) resulted in a similar accuracy for the detection of CCA. Finally, for the convenience of operation, a user-friendly prediction platform was built online for CCA.

CONCLUSIONS

This is the largest and most comprehensive study combining bile and serum biomarkers to differentiate CCA. This diagnostic model may potentially be used to detect CCA.

High Level of Serum Coiled-coil Domain Containing 25 (CCDC25) as a Diagnostic Marker for Cholangiocarcinoma But Not for Other Cancers

BACKGROUND/AIM

Recently, we reported that coiled-coil domain containing 25 (CCDC25) protein is elevated in the sera of patients with cholangiocarcinoma (CCA) and is suggested to be a diagnostic biomarker for CCA. This study aimed to examine whether serum CCDC25 level can be a unique biomarker for CCA. Bioinformatic analyses using Human Protein Atlas (HPA) database and Gene Expression Profiling Interactive Analysis 2 (GEPIA2) indicated that CCDC25 protein and mRNA are expressed not only in CCA but also in other cancers, such as colorectal cancer (CRC), breast cancer (BC), and hepatocellular carcinoma (HCC), all of which are the top 5 cancers highly prevalent in Thailand.

MATERIALS AND METHODS

Using a quantitative dot blot assay, serum CCDC25 levels were measured for 30 healthy controls (HC), 34 CRC, 42 BC, 43 HCC, and 83 CCA.

RESULTS

The serum CCDC25 levels of CCA patients (0.193±0.039 ng/μl) were significantly higher than those of CRC (0.019±0.006 ng/μl), BC (0.036±0.015 ng/μl), HCC (0.035±0.016 ng/μl), and higher than those of HC (0.012±0.003 ng/μl). The serum CCDC25 level can discriminate CCA from the HC, CRC, BC, and HCC with a sensitivity of 100, 99, 94, and 94%, respectively, and specificity of 100, 100, 98, and 95%, respectively.

CONCLUSION

CCDC25 is a candidate diagnostic biomarker for CCA.

Development and validation of circulating protein signatures as diagnostic biomarkers for biliary tract cancer

Background & Aims

Biliary tract cancer (BTC) is associated with a dismal prognosis, partly because it is typically diagnosed late, highlighting the need for diagnostic biomarkers. The purpose of this project was to identify and validate multiprotein signatures that could differentiate patients with BTC from non-cancer controls.

Methods

In this study, we included treatment-naïve patients with BTC, healthy controls, and patients with benign conditions including benign biliary tract disease. Participants were divided into three non-overlapping cohorts: a case-control-based discovery cohort (BTC = 186, controls = 249); a case-control-based validation cohort (validation cohort 1: BTC = 113, controls = 241); and a cohort study-based validation cohort including participants (BTC = 8, controls = 132) referred for diagnostic work-up for suspected cancer (validation cohort 2). Immuno-Oncology (I-O)-related proteins were measured in serum and plasma using a proximity extension assay (Olink Proteomics). Lasso and Ridge regressions were used to generate protein signatures of I-O-related proteins and carbohydrate antigen 19-9 (CA19-9) in the discovery cohort.

Results

Sixteen protein signatures, including 2 to 82 proteins, were generated. All signatures included CA19-9 and chemokine C-C motif ligand 20. Signatures discriminated between patients with BTC vs. controls, with AUCs ranging from 0.95 to 0.99 in the discovery cohort and 0.94 to 0.97 in validation cohort 1. In validation cohort 2, AUCs ranged from 0.84 to 0.94. Nine signatures achieved a specificity of 82% to 84% while keeping a sensitivity of 100% in validation cohort 2. All signatures performed better than CA19-9, and signatures including >15 proteins showed the best performance.

Conclusion

The study demonstrated that it is possible to generate protein signatures that can successfully differentiate patients with BTC from non-cancer controls.

Impact and implications

We attempted to find blood sample-based protein profiles that could differentiate patients with biliary tract cancer from those without cancer. Several profiles were found and tested in different groups of patients. The profiles were successful at identifying most patients with biliary tract cancer, pointing towards the utility of multiprotein signatures in this context.

Liver transplantation and intrahepatic cholangiocarcinoma: time to go forward again?

PURPOSE OF REVIEW

Liver transplantation for intrahepatic cholangiocarcinoma (iCCA) has been mired in controversy. High rates of recurrence posttransplant combined with donor organ scarcity resulted in most transplant centers treating iCCA as a contraindication for liver transplantation.

RECENT FINDINGS

Recent studies have shown that carefully selected patients with unresectable iCCA can have good outcomes after liver transplantation. Better outcomes have been seen in patients with smaller tumors and favorable tumor biology.

SUMMARY

Because many patients are diagnosed with iCCA at later stages, tumor biology and genetics are useful tools to identify patients who will have excellent overall and recurrence-free survival after liver transplantation. Further larger multicenter prospective studies are needed to identify patients who would benefit from liver transplantation with good outcomes. Additional advances will come through early diagnosis and utilizing a combination of chemotherapy and locoregional modalities as a bridge to transplant. There is also a need to recognize and develop additional neo- and adjuvant therapies for patients whose tumor biology currently precludes their inclusion on the liver transplantation waitlist.

Novel approaches in search for biomarkers of cholangiocarcinoma

Cholangiocarcinoma (CCA) arises from the ductular epithelium of the biliary tree, either within the liver (intrahepatic CCA) or more commonly from the extrahepatic bile ducts (extrahepatic CCA). This disease has a poor prognosis and a growing worldwide prevalence. The poor outcomes of CCA are partially explained by the fact that a final diagnosis is challenging, especially the differential diagnosis between hepatocellular carcinoma and intrahepatic CCA, or distal CCA and pancreatic head adenocarcinoma. Most patients present with an advanced disease, unresectable disease, and there is a lack in non-surgical therapeutic modalities. Not least, there is an acute lack of prognostic biomarkers which further complicates disease management. Therefore, there is a dire need to find alternative diagnostic and follow-up pathways that can lead to an accurate result, either singlehandedly or combined with other methods. In the "-omics" era, this goal can be attained by various means, as it has been successfully demonstrated in other primary tumors. Numerous variants can reach a biomarker status ranging from circulating nucleic acids to proteins, metabolites, extracellular vesicles, and ultimately circulating tumor cells. However, given the relatively heterogeneous data, extracting clinical meaning from the inconsequential noise might become a tall task. The current review aims to navigate the nascent waters of the non-invasive approach to CCA and provide an evidence-based input to aid clinical decisions and provide grounds for future research.

Biomarkers and Genetic Markers of Hepatocellular Carcinoma and Cholangiocarcinoma-What Do We Already Know

Simple Summary

Hepatocellular carcinoma and cholangiocarcinoma continue to remain a serious threat. In this review, we describe the most common biomarkers and genetic markers currently used in the diagnosis of hepatocellular carcinoma and cholangiocarcinoma. It can be observed that biomarkers and genetic markers might be applied in various parts of diagnosis including screening tests in a high-risk group, non-invasive detection, control of therapy, treatment selection, and control of recurrence. Also, it can be seen that nowadays there is a need for more specific markers that would improve the detection in early or very early stages of both types of cancers and further research should be focused on it.

Abstract

Hepatocellular carcinoma (HCC) is the most common primary liver cancer with an increasing worldwide mortality rate. Cholangiocarcinoma (CCA) is the second most common primary liver cancer. In both types of cancers, early detection is very important. Biomarkers are a relevant part of diagnosis, enabling non-invasive detection and control of cancer recurrence, as well as in the application of screening tests in high-risk groups. Furthermore, some of these biomarkers are useful in controlling therapy and treatment selection. Detection of some markers presents higher sensitivity and specificity in combination with other markers when compared with a single detection. Some gene aberrations are also prognostic markers in the two types of cancers. In the following review, we discuss the most common biomarkers and genetic markers currently being used in the diagnosis of hepatocellular carcinoma and cholangiocarcinoma.

Limits of serum carcinoembryonic antigen and carbohydrate antigen 19-9 as the diagnosis of gallbladder cancer

Purpose

Although serum CEA and CA 19-9 have been widely utilized for the diagnosis of gallbladder cancer (GBC), few studies have examined the diagnostic performance of them. This study aimed to investigate the diagnostic performance of these 2 biomarkers and demonstrate their clinical usefulness in diagnosing GBC.

Methods

Between January 2000 and March 2020, a total of 751 GBC patients and 2,310 normal controls were included. Serum CEA and CA 19-9 were measured preoperatively. Receiver operating characteristic curves were obtained, and the sensitivity and specificity of each biomarker were evaluated.

Results

In terms of differentiating GBC from the control, the sensitivity and specificity of serum CEA at 5 ng/mL was 12.1% and 99.1%, respectively, and those of serum CA 19-9 at 37 IU/mL were 28.7% and 94.5%, respectively. The optimal cutoff values of CEA and CA 19-9 were set to 2.1 ng/mL and 26 IU/mL in the receiver operating characteristic curves, respectively. The sensitivities of CEA and CA 19-9 at new cutoff values slightly increased but remained low (CEA, 42.9%; CA 19-9, 38.2%). When differentiating early-stage GBC from advanced tumor, the sensitivity and specificity, were 14.2% and 96.1% for CEA (cutoff value, 5 ng/mL) and 33.6% and 90.1% for CA 19-9 (cutoff value, 37 IU/mL), respectively.

Conclusion

Serum CEA and CA 19-9 levels are not suitable for screening GBC patients from controls. New promising biomarkers with higher sensitivity should be explored.

Biliary Strictures and Cholangiocarcinoma - Untangling a Diagnostic Conundrum

Cholangiocarcinoma is an uncommon and highly aggressive biliary tract malignancy with few manifestations until late disease stages. Diagnosis is currently achieved through a combination of clinical, biochemical, radiological and histological techniques. A number of reported cancer biomarkers have the potential to be incorporated into diagnostic pathways, but all lack sufficient sensitivity and specificity limiting their possible use in screening and early diagnosis. The limitations of standard serum markers such as CA19-9, CA125 and CEA have driven researchers to identify multiple novel biomarkers, yet their clinical translation has been slow with a general requirement for further validation in larger patient cohorts. We review recent advances in the diagnostic pathway for suspected CCA as well as emerging diagnostic biomarkers for early detection, with a particular focus on non-invasive approaches.

Electrochemical detection of matrix metalloproteinase-7 using an immunoassay on a methylene blue/2D MoS2/graphene oxide electrode

Methylene blue (MB) adsorption onto a two-dimensional molybdenum disulfide (2D MoS₂)/graphene oxide (GO) nanocomposite sitting on a screen-printed carbon electrode (SPCE) is used to develop a new sensitive label-free electrochemical immunosensor for the detection of matrix metalloproteinase-7 (MMP-7) cancer biomarkers. The 2D MoS₂/GO nanocomposite deposited onto an SPCE provides a large specific surface area, fast electron transfer, and exceptional electrical conductivity. Furthermore, MB adsorbed onto the 2D MoS₂/GO nanocomposite architecture can be used for signal amplification in electrochemical immunosensors. Moreover, an immunosensor platform was fabricated by the adsorption of anti-MMP-7 capture antibodies onto the MB/2D MoS₂/GO nanocomposite surface via electrostatic interactions for the detection of the MMP-7 immunocomplex. Under optimum conditions, the label-free immunosensor exhibits a decrease in the current response for MB corresponding to the MMP-7 concentration. The sensor affords a linear logarithmic range of 0.010-75 ng mL^-1 with a limit of detection (LOD) of 0.007 ng mL^-1. The developed electrochemical immunosensor provides high selectivity, good reproducibility, and excellent stability. Furthermore, the proposed immunosensor can be applied for the detection of MMP-7 in human serum samples with good recovery. Thus, this device can be applied for the early clinical diagnosis of pancreatic and colorectal cancers.

A Rare Case of Caroli's Syndrome

Caroli's syndrome is a rare autosomal recessive congenital disorder of the biliary tree characterized by intrahepatic bile duct dilation and hepatic fibrosis. Very few cases have been encountered in routine day-to-day practice. The patients usually present with features of cholangitis such as pain abdomen and jaundice. They may also present with features of chronic liver disease and portal hypertension. Very rarely, they may develop cholangiocarcinoma and present with jaundice, weight loss, and abdominal mass or ascites. Here, we report one such case of a young female who presented to us with features of cholangitis with sepsis and encephalopathy, which was finally diagnosed as Caroli's syndrome. The aim of presenting this case is to learn that even patients with common symptoms of pain abdomen and jaundice may be harboring some rare congenital disease like Caroli's syndrome, as in our case.

Plasma checkpoint protein 1 (Chk1) as a potential diagnostic biomarker for opisthorchiasis and cholangiocarcinoma

BACKGROUND

Patients infected with a parasite often develop opisthorchiasis viverrini, which often progresses into cholangiocarcinoma (CCA) due to the asymptomatic nature of the infection. Currently, there are no effective diagnostic methods for opisthorchiasis or cholangiocarcinoma.

OBJECTIVE

The aim of this study was to identify the host-responsive protein that can be developed as a diagnostic biomarker of opisthorchiasis and cholangiocarcinoma.

METHODS

Plasma samples were collected from non-OVCCA, OV, and CCA subjects, and the proteomes were investigated by LC-MS/MS. Venn diagrams and protein network prediction by STITCH were used to identify the potential biomarkers. The level of candidate protein, the plasma checkpoint protein 1 (Chk1), was measured by indirect enzyme-linked immunosorbent assay (ELISA).

RESULTS

Chk1 was present in the center of the protein network analysis in both the OV and CCA groups. In addition, the plasma Chk1 levels were significantly increased in both groups (P< 0.05). The sensitivity of the opisthorchiasis viverrini and cholangiocarcinoma was 59.38% and 65.62%, respectively, while the specificity of both was 85.71%.

CONCLUSION

Chk1 was identified by differential plasma proteomes and was increased in O. viverrini-infected and cholangiocarcinoma-derived plasma samples. Higher levels of plasma Chk1 levels may serve as a potential diagnostic biomarker for opisthorchiasis and cholangiocarcinoma.

Next-Generation Biomarkers for Cholangiocarcinoma

Simple Summary

Early and non-invasive diagnosis of cholangiocarcinoma (CCA) is still challenging, thus largely contributing to the increased mortality rates observed worldwide. Consequently, several efforts have been made in order to report novel biomarkers for CCA, that would aid on diagnosis and also to predict prognosis and therapy response. We herein aim to provide an in-depth and critical revision on the next-generation biomarkers for CCA that have been recently proposed.

Abstract

The increasing mortality rates of cholangiocarcinoma (CCA) registered during the last decades are, at least in part, a result of the lack of accurate non-invasive biomarkers for early disease diagnosis, making the identification of patients who might benefit from potentially curative approaches (i.e., surgery) extremely challenging. The obscure CCA pathogenesis and associated etiological factors, as well as the lack of symptoms in patients with early tumor stages, highly compromises CCA identification and to predict tumor development in at-risk populations. Currently, CCA diagnosis is accomplished by the combination of clinical/biochemical features, radiological imaging and non-specific serum tumor biomarkers, although a tumor biopsy is still needed to confirm disease diagnosis. Furthermore, prognostic and predictive biomarkers are still lacking and urgently needed. During the recent years, high-throughput omics-based approaches have identified novel circulating biomarkers (diagnostic and prognostic) that might be included in large, international validation studies in the near future. In this review, we summarize and discuss the most recent advances in the field of biomarker discovery in CCA, providing new insights and future research directions.

Liquid biopsy in cholangiocarcinoma: Current status and future perspectives

Cholangiocarcinoma (CCA) are a heterogeneous group of tumors in terms of aetiology, natural history, morphological subtypes, molecular alterations and management, but all sharing complex diagnosis, management, and poor prognosis. Several mutated genes and epigenetic changes have been detected in CCA, with the potential to identify diagnostic and prognostic biomarkers and therapeutic targets. Accessing tumoral components and genetic material is therefore crucial for the diagnosis, management and selection of targeted therapies; but sampling tumor tissue, when possible, is often risky and difficult to be repeated at different time points. Liquid biopsy (LB) represents a way to overcome these issues and comprises a diverse group of methodologies centering around detection of tumor biomarkers from fluid samples. Compared to the traditional tissue sampling methods LB is less invasive and can be serially repeated, allowing a real-time monitoring of the tumor genetic profile or the response to therapy. In this review, we analysis the current evidence on the possible roles of LB (circulating DNA, circulating RNA, exosomes, cytokines) in the diagnosis and management of patients affected by CCA.

Targeting Aspartate Beta-Hydroxylase with the Small Molecule Inhibitor MO-I-1182 Suppresses Cholangiocarcinoma Metastasis

BACKGROUND

Cholangiocarcinoma is a devastating disease with a 2% 5-year survival if the disease has spread outside the liver. The enzyme aspartate beta-hydroxylase (ASPH) has been demonstrated to be highly expressed in cholangiocarcinoma but not in normal bile ducts and found to stimulate tumor cell migration. In addition, it was found that targeting ASPH inhibits cholangiocarcinoma malignant progression. However, it is not clear whether targeting ASPH with the small molecule inhibitor MO-I-1182 suppresses cholangiocarcinoma metastasis. The current study aims to study the efficacy of MO-I-1182 in suppressing cholangiocarcinoma metastasis.

METHODS

The analysis was performed in vitro and in vivo with a preclinical animal model by using molecular and biochemical strategies to regulate ASPH expression and function.

RESULTS

Knockdown of ASPH substantially inhibited cell migration and invasion in two human cholangiocarcinoma cell lines. Targeting ASPH with a small molecule inhibitor suppressed cholangiocarcinoma progression. Molecular mechanism studies demonstrated that knockdown of ASPH subsequently suppressed protein levels of the matrix metalloproteinases. The ASPH knockdown experiments suggest that this enzyme may modulate cholangiocarcinoma metastasis by regulating matrix metalloproteinases expression. Furthermore, using an ASPH inhibitor in a rat cholangiocarcinoma intrahepatic model established with BED-Neu-CL#24 cholangiocarcinoma cells, it was found that targeting ASPH inhibited intrahepatic cholangiocarcinoma metastasis and downstream expression of the matrix metalloproteinases.

CONCLUSION

ASPH may modulate cholangiocarcinoma metastasis via matrix metalloproteinases expression. Taken together, targeting ASPH function may inhibit intrahepatic cholangiocarcinoma metastasis and improve survival.

Promoter hypermethylation of early B cell factor 1 (EBF1) is associated with cholangiocarcinoma progression

DNA hypermethylation in a promoter region causes gene silencing via epigenetic changes. We have previously reported that early B cell factor 1 (EBF1) was down-regulated in cholangiocarcinoma (CCA) tissues and related to tumor progression. Thus, we hypothesized that the DNA hypermethylation of EBF1 promoter would suppress EBF1 expression in CCA and induce its progression. In this study, the DNA methylation status of EBF1 and mRNA expression levels were analyzed in CCA and normal bile duct (NBD) tissues using a publicly available database of genome-wide association data. The results showed that the DNA methylation of EBF1 promoter region was significantly increased in CCA tissues compared with those of NBD. The degree of methylation was negatively correlated with EBF1 mRNA expression levels. Using methylation-specific PCR technique, the DNA methylation rates of EBF1 promoter region were investigated in CCA tissues (n=72). CCA patients with high methylation rates of EBF1 promoter region in the tumor tissues (54/72) had a poor prognosis. Higher methylation rates of EBF1 promoter region have shown in all CCA cell lines than that of an immortal cholangiocyte cell line (MMNK1). Upon treatment with the DNA methyltransferase inhibitor 5-Aza-dC, increased EBF1 expression levels and reduced DNA methylation rates were observed in CCA cells. Moreover, restoration of EBF1 expression in CCA cells led to inhibition of cell growth, migration and invasion. In addition, RNA sequencing analysis suggested that EBF1 is involved in suppression of numerous pathways in cancer. Taken together, DNA hypermethylation in the EBF1 promoter region suppresses EBF1 expression and induces CCA progression with aggressive clinical outcomes.

Neoadjuvant treatment strategies for intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver malignancy and is increasing in incidence. Long-term outcomes are optimized when patients undergo margin-negative resection followed by adjuvant chemotherapy. Unfortunately, a significant proportion of patients present with locally advanced, unresectable disease. Furthermore, recurrence rates are high even among patients who undergo surgical resection. The delivery of systemic and/or liver-directed therapies prior to surgery may increase the proportion of patients who are eligible for surgery and reduce recurrence rates by prioritizing early systemic therapy for this aggressive cancer. Nevertheless, the available evidence for neoadjuvant therapy in ICC is currently limited yet recent advances in liver directed therapies, chemotherapy regimens, and targeted therapies have generated increasing interest its role. In this article, we review the rationale for, current evidence for, and ongoing research efforts in the use of neoadjuvant therapy for ICC.

Omics-Based Platforms: Current Status and Potential Use for Cholangiocarcinoma

Cholangiocarcinoma (CCA) has been identified as a highly malignant cancer that can be transformed from epithelial cells of the bile duct, including intrahepatic, perihilar and extrahepatic. High-resolution imaging tools (abdominal ultrasound, computed tomography and percutaneous transhepatic cholangial drainage) are recruited for diagnosis. However, the lack of early diagnostic biomarkers and treatment evaluation can lead to serious outcomes and poor prognosis (i.e., CA19-9, MUC5AC). In recent years, scientists have established a large number of omics profiles to reveal underlying mechanisms and networks (i.e., IL-6/STAT3, NOTCH). With these results, we achieved several genomic alteration events (i.e., TP53_mut, KRAS_mut) and epigenetic modifications (i.e., DNA methylation, histone modification) in CCA cells and clinical patients. Moreover, we reviewed candidate gene (such as NF-kB, YAP1) that drive gene transcription factors and canonical pathways through transcriptomics profiles (including microarrays and next-generation sequencing). In addition, the proteomics database also indicates which molecules and their directly binding status could trigger dysfunction signatures in tumorigenesis (carbohydrate antigen 19-9, mucins). Most importantly, we collected metabolomics datasets and pivotal metabolites. These results reflect the pharmacotherapeutic options and evaluate pharmacokinetic/pharmacodynamics in vitro and in vivo. We reversed the panels and selected many potentially small compounds from the connectivity map and L1000CDS² system. In this paper, we summarize the prognostic value of each candidate gene and correlate this information with clinical events in CCA. This review can serve as a reference for further research to clearly investigate the complex characteristics of CCA, which may lead to better prognosis, drug repurposing and treatment strategies.

Cholangiocarcinoma 2020: the next horizon in mechanisms and management

Cholangiocarcinoma (CCA) includes a cluster of highly heterogeneous biliary malignant tumours that can arise at any point of the biliary tree. Their incidence is increasing globally, currently accounting for ~15% of all primary liver cancers and ~3% of gastrointestinal malignancies. The silent presentation of these tumours combined with their highly aggressive nature and refractoriness to chemotherapy contribute to their alarming mortality, representing ~2% of all cancer-related deaths worldwide yearly. The current diagnosis of CCA by non-invasive approaches is not accurate enough, and histological confirmation is necessary. Furthermore, the high heterogeneity of CCAs at the genomic, epigenetic and molecular levels severely compromises the efficacy of the available therapies. In the past decade, increasing efforts have been made to understand the complexity of these tumours and to develop new diagnostic tools and therapies that might help to improve patient outcomes. In this expert Consensus Statement, which is endorsed by the European Network for the Study of Cholangiocarcinoma, we aim to summarize and critically discuss the latest advances in CCA, mostly focusing on classification, cells of origin, genetic and epigenetic abnormalities, molecular alterations, biomarker discovery and treatments. Furthermore, the horizon of CCA for the next decade from 2020 onwards is highlighted.

Analysis of differentially expressed mRNAs and the prognosis of cholangiocarcinoma based on TCGA database

Background

The effective evaluation of cholangiocarcinoma (CCA) is challenging due to a lack of accurate screening tools. Consequently, there is an urgent need to screen out effective biomarkers. Bioinformatics analysis on a substantial amount of transcriptomic data to screen biomolecules allows for the verification of histological samples, and can provide a new method for CCA biomolecule screening in diagnosis and prognosis.

Methods

EdgeR model was used to analyze The Cancer Genome Atlas (TCGA)-extracted CCA data set, and to determine the differential expression of mRNAs. Based on this, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to perform functional and pathway enrichment analysis. Subsequently, a protein interaction network was also established to identify the key differential node genes. Then, the previously determined differential genes were analyzed to establish a link between these genes and clinical prognosis. Finally, we used tissue samples to realize our results via IHC, Western blot and qRT-PCR.

Results

A total of 5,561 differential mRNAs were screened, including 3,473 upregulated genes and 2,088 downregulated genes. GO and KEGG enrichment analysis showed that the upregulated genes had significantly enriched cell adhesion, concentrated chromosomal motility, and microtubule motility. Downregulated genes were significantly enriched in heterologous metabolism and exosomes. Furthermore, we found upregulated genes were significantly enriched in the cancer pathways and cell cycle. Downregulated genes were enriched in the metabolic pathways and biosynthesis of antibiotics. Ten hub genes were screened out through the protein interaction network; among these, the AURKB and PLK1 genes were closely related to the clinical prognosis of patients. Results of the immunohistochemical staining, Western blot and qRT-PCR all showed that the expression of AURKB and PLK1 in cancer tissues was higher than that in the adjacent tissues, and this difference was statistically significant (P<0.05).

Conclusions

The upregulated genes were significantly enriched in the biological processes of cell division, cell cycle, and related cell components. AURKB and PLK1 play a key role in differentially expressed gene nodes. These genes are closely related to the prognosis of patients and can be used as potential diagnostic tools and prognostic biomarkers.

Diagnostic and prognostic biomarkers in cholangiocarcinoma

The high mortality rate of cholangiocarcinoma (CCA) is due, in part, to the lack of non-invasive approaches able to accurately detect this silent tumour at early stages, when therapeutic options can be potentially curative or may at least increase the overall survival of patients. The fact that the majority of CCA tumours are not linked to any known aetiological factor highly compromises the monitoring of patients at risk for tumour development and also their early diagnosis. Combination of clinical/biochemical features, imaging techniques and analysis of non-specific tumour biomarkers in serum are commonly used to help in the diagnosis of CCA, but tumour biopsy is usually required to confirm the diagnosis. Moreover, no prognostic biomarkers are currently used in the clinical setting, deserving more innovative research, and international validation and consensus. Important efforts have been made in the last few years to identify accurate non-invasive biomarkers, by using innovative techniques and high-throughput omics technologies. This review summarizes and discusses the advances in the investigation of novel diagnostic and prognostic biomarkers in CCA and envisions the future directions in this field of research.

Electrochemical Activity Assay for Protease Analysis Using Carbon Nanofiber Nanoelectrode Arrays

There is a strong demand for bioanalytical techniques to rapidly detect protease activities with high sensitivity and high specificity. This study reports an activity-based electrochemical method toward this goal. Nanoelectrode arrays (NEAs) fabricated with embedded vertically aligned carbon nanofibers (VACNFs) are functionalized with specific peptide substrates containing a ferrocene (Fc) tag. The kinetic proteolysis curves are measured with continuously repeated ac voltammetry, from which the catalytic activity is derived as the inverse of the exponential decay time constant based on a heterogeneous Michaelis-Menten model. Comparison of three peptide substrates with different lengths reveals that the hexapeptide H2N-(CH2)4-CO-Pro-Leu-Arg-Phe-Gly-Ala-NH-CH2-Fc is the optimal probe for cathepsin B. The activity strongly depends on temperature and is the highest around the body temperature. With the optimized peptide substrate and measuring conditions, the limit of detection of cathepsin B activity and concentration can reach 2.49 × 10-4 s-1 and 0.32 nM, respectively. The peptide substrates show high specificity to the cognate proteases, with negligible cross-reactions among three cancer-related proteases cathepsin B, ADAM10, and ADAM17. This electrochemical method can be developed into multiplex chips for rapid profiling of protease activities in cancer diagnosis and treatment monitoring.

Serum cell-free DNA methylation of OPCML and HOXD9 as a biomarker that may aid in differential diagnosis between cholangiocarcinoma and other biliary diseases

BACKGROUND

Cholangiocarcinoma (CCA) is a fatal cancer of the bile duct epithelial cell lining. The misdiagnosis of CCA and other biliary diseases may occur due to the similarity of clinical manifestations and blood tests resulting in inappropriate or delayed treatment. Thus, an accurate and less-invasive method for differentiating CCA from other biliary diseases is inevitable.

METHODS

We quantified methylation of OPCML, HOXA9, and HOXD9 in serum cell-free DNA (cfDNA) of CCA patients and other biliary diseases using methylation-sensitive high-resolution melting (MS-HRM). Their potency as differential biomarkers between CCA and other biliary diseases was also evaluated by using receiver operating characteristic (ROC) curves.

RESULTS

The significant difference of methylation levels of OPCML and HOXD9 was observed in serum cfDNA of CCA compared to other biliary diseases. Assessment of serum cfDNA methylation of OPCML and HOXD9 as differential biomarkers of CCA and other biliary diseases showed the area under curve (AUC) of 0.850 (0.759-0.941) for OPCML which sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 80.00%, 90.00%, 88.88%, 81.81%, and 85.00%, respectively. The AUC of HOXD9 was 0.789 (0.686-0.892) with sensitivity, specificity, PPV, NPV, and accuracy of 67.50%, 90.00%, 87.09%, 73.46%, and 78.75%, respectively. The combined marker between OPCML and HOXD9 showed sensitivity, specificity, PPV, and NPV of 62.50%, 100%, 100%, and 72.72%, respectively, which may be helpful to prevent a misdiagnosis between CCA and other biliary diseases.

CONCLUSIONS

Our findings suggest the application of serum cfDNA methylation of OPCML and HOXD9 for differential diagnosis of CCA and other biliary diseases due to its less invasiveness and clinically practical method which may benefit the patients by preventing the misdiagnosis of CCA and avoiding unnecessary surgical intervention.

Circulating Biomarkers for Cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) represents the second most common primary liver malignancy. The incidence rate has constantly increased over the last decades and CCA patients face a dismal prognosis with a 5-year survival rate of less than 5% for advanced stage of disease. Surgical tumor resection has remained the only potentially curative treatment option in daily practice but is often not feasible due to advanced disease stage at initial diagnosis.

SUMMARY

The early detection of cholangiocarcinoma is essential to provide patients with a potentially curative treatment. Furthermore, prognostic biomarkers represent a valuable tool to offer patients a tailored therapeutic approach in accordance to their life expectancy. The clinically most established biomarker carbohydrate antigen 19-9 shows only a limited diagnostic and prognostic power, encouraging the evaluation of novel biomarkers for cholangiocarcinoma in the last years. Key Massage: In this review, we assess currently available and potential future biomarkers for the diagnosis and prognosis of cholangicarcinoma.

A novel nomogram for the prediction of intrahepatic cholangiocarcinoma in patients with intrahepatic lithiasis complicated by imagiologically diagnosed mass

Background

Accurate preoperative diagnosis of intrahepatic cholangiocarcinoma (ICC) among patients with imagiologically intrahepatic lithiasis (IHL) complicated by mass is crucial for timely and effective surgical intervention. The aim of the present study was to develop a nomogram to identify ICC associated with IHL (IHL-ICC).

Patients and methods

Data were obtained from a total of 252 consecutive patients with IHL complicated by mass. Multivariate logistic regression analysis was conducted to identify the clinicopathologic and imagiological characteristics that were potentially associated with ICC. A nomogram was developed based on the results of the multivariate analysis, and the value for prediction of ICC was assessed.

Results

The study revealed six potential predictors for IHL-ICC, including comprehensive imagiological diagnosis, biliary tract operation history, fever, ascites, cancer antigen (CA) 19-9, and carcinoembryonic antigen (CEA). The optimal cutoff value was 3.75 μg/L for serum CEA and 143.15 U/mL for serum CA 19-9. The accuracy of the nomogram in predicting ICC was 78.5%. The Youden index provided a value of 0.348, corresponding to a cutoff of 95 points, with an area under the curve of 0.863.

Conclusion

The nomogram holds promise as a novel and accurate tool in identifying IHL-ICC for hepatectomy, and in the differentiation of benign occupying lesions in IHL patients, resulting in the avoidance of unnecessary surgical resection.

Multiplex Serum Protein Analysis Identifies Novel Biomarkers of Advanced Fibrosis in Patients with Chronic Liver Disease with the Potential to Improve Diagnostic Accuracy of Established Biomarkers

Background and Aims

Non-invasive markers of liver fibrosis are urgently required, especially for use in non-specialist settings. The aim of this study was to identify novel serum biomarkers of advanced fibrosis.

Methods

We performed an unbiased screen of 120 serum analytes including cytokines, chemokines and proteases in 70 patients (35 without fibrosis, 35 with cirrhosis on biopsy), and selected a panel of 44 candidate biomarkers, which were subsequently measured in a mixed-etiology cohort of 432 patients with known serum HA, PIIINP and TIMP1 (which comprise the validated Enhanced Liver Fibrosis (ELF) test). Multivariate logistic regression modelling was used to generate models for the prediction of advanced or significant fibrosis (METAVIR ≥F3 and ≥F2, respectively); in addition to identifying biomarkers of disease activity and steatohepatitis.

Results

Seventeen analytes were significantly differentially expressed between patients with no advanced fibrosis and patients with advanced fibrosis, the most significant being hyaluronic acid (HA) and matrix metalloproteinase (MMP) 7 (p = 2.9E-41 and p = 1.0E-26, respectively). The optimal model for the prediction of advanced fibrosis comprised HA, MMP7, MMP1, alphafetoprotein (AFP) and the AST to platelet ratio index (APRI). We demonstrate enhanced diagnostic accuracy (AUROC = 0.938) compared to a model comprising HA, PIIINP and TIMP1 alone (ELF) (AUROC = 0.898, p<0.0001, De Long’s test).

Conclusions

We have identified novel serum biomarkers of advanced liver fibrosis, which have the potential to enhance the diagnostic accuracy of established biomarkers. Our data suggest MMP7 is a valuable indicator of advanced fibrosis and may play a role in liver fibrogenesis.

Advances in biomarkers of biliary tract cancers

Tumor biomarkers can be applied for early diagnosis or precise treatment, thereby leading to personalized treatment and better outcomes. Biliary tract cancers (BTCs) are a group of cancers that occurs in different locations and have different clinical or genetic properties. Though the incidence of BTCs is rare, BTCs are among the most lethal cancers in the world and all have very low 5-year survivals. Lack of efficient early diagnostic approaches or adjuvant therapies for BTCs are main reasons. These urge us to broaden the researches into BTC biomarkers. Although few progresses of diagnostic biomarkers for BTCs have been achieved, there are still some advances in prognostic, predictive and therapeutic areas. In this review, we will focus on these achievements.

Cholangiocarcinoma: Current opinion on clinical practice diagnostic and therapeutic algorithms: A review of the literature and a long-standing experience of a referral center

In the oncology landscape, cholangiocarcinoma is a challenging disease in terms of both diagnosis and treatment. Besides anamnesis and clinical examination, a definitive diagnosis of cholangiocarcinoma should be supported by imaging techniques (US, CT, MRI) and invasive investigations (ERC or EUS with brushing and FNA or US or CT-guided biopsy) followed by pathological confirmation. Surgery is the main curative option, so resectability of the tumour should be promptly assessed. Moreover, jaundice must be evaluated at the outset because biliary tract decompression with drainage and stent placement may be required. If the patient is resectable, pre-operative assessment of postoperative liver function is mandatory. After a curative resection, an adjuvant therapy may be administered. Otherwise, in cases with macroscopic residual disease after surgery or locally recurrent or unresectable cholangiocarcinoma at the diagnosis, first-line chemotherapy is the preferred strategy, possibly associated with radiotherapy and/or locoregional treatments. As the diagnostic and therapeutic pathway for cholangiocarcinoma can be declined in different modalities, patients should be promptly referred to a multidisciplinary team in a tertiary centre, familiar with this rare but lethal disease. Hence, the aim of the present paper is to focus on diagnostic and therapeutic algorithms based on the common guidelines and also on the clinical practice of multispecialist expert groups.

Serum and biliary MMP-9 and TIMP-1 concentrations in the diagnosis of cholangiocarcinoma

AIM

Cholangiocarcinoma is generally detected late in the course of disease, and current diagnostic techniques often fail to differentiate benign from malignant disease. Ongoing biomarker studies for early diagnosis of cholangiocarcinoma are still continues. By this study, we analyzed the roles of serum and biliary MMP-9 and TIMP-1 concentrations in the diagnosis of cholangiocarcinoma.

MATERIALS AND METHODS

The 113 patients (55 males, 58 females) were included; 33 diagnosed with cholangiocarcinoma (malignant group) and 80 diagnosed with choledocholithiasis (benign group). MMP-9 and TIMP-1 concentrations were analyzed in serum and bile and compared in the malignant and benign groups. Results were evaluated statistically.

RESULTS

Biliary MMP-9 concentrations were significantly higher (576 ± 209 vs. 403 ± 140 ng/ml, p < 0.01) and biliary TIMP-1 concentrations were significantly lower (22.4 ± 4.9 vs. 29.4 ± 6.1 ng/ml, p < 0.01) in the malignant than in the benign group. In contrast, serum MMP-9 and TIMP-1 concentrations were similar in the two groups. Receiver operating curve analysis revealed that the areas under the curve of bile MMP-9 and TIMP-1 were significantly higher than 0.5 (p < 0.001). The sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios and accuracy were 0.94, 0.32, 0.36, 0.93, 1.40, 0.19 and 0.5 for biliary MMP-9, respectively, and 0.97, 0.36, 0.39, 0.97, 1.5, 0.08 and 0.54 for biliary TIMP-1, respectively.

CONCLUSION

Serum and biliary MMP-9 and TIMP-1 tests do not appear to be useful in the diagnosis of cholangiocarcinoma.

A multiplexable, microfluidic platform for the rapid quantitation of a biomarker panel for early ovarian cancer detection at the point-of-care

Point-of-care (POC) diagnostic platforms have the potential to enable low-cost, large-scale screening. As no single biomarker is shed by all ovarian cancers, multiplexed biomarker panels promise improved sensitivity and specificity to address the unmet need for early detection of ovarian cancer. We have configured the programmable bio-nano-chip (p-BNC)-a multiplexable, microfluidic, modular platform-to quantify a novel multi-marker panel comprising CA125, HE4, MMP-7, and CA72-4. The p-BNC is a bead-based immunoanalyzer system with a credit-card-sized footprint that integrates automated sample metering, bubble and debris removal, reagent storage and waste disposal, permitting POC analysis. Multiplexed p-BNC immunoassays demonstrated high specificity, low cross-reactivity, low limits of detection suitable for early detection, and a short analysis time of 43 minutes. Day-to-day variability, a critical factor for longitudinally monitoring biomarkers, ranged between 5.4% and 10.5%, well below the biologic variation for all four markers. Biomarker concentrations for 31 late-stage sera correlated well (R(2) = 0.71 to 0.93 for various biomarkers) with values obtained on the Luminex platform. In a 31 patient cohort encompassing early- and late-stage ovarian cancers along with benign and healthy controls, the multiplexed p-BNC panel was able to distinguish cases from controls with 68.7% sensitivity at 80% specificity. Utility for longitudinal biomarker monitoring was demonstrated with prediagnostic plasma from 2 cases and 4 controls. Taken together, the p-BNC shows strong promise as a diagnostic tool for large-scale screening that takes advantage of faster results and lower costs while leveraging possible improvement in sensitivity and specificity from biomarker panels.

Diagnostic and prognostic serum marker of cholangiocarcinoma (Review)

Cholangiocarcinoma (CCA) is a fatal disease that is typically diagnosed late and treated ineffectively. As the morbidity and mortality rates for CCA rise markedly, patietns with CCA currently have a poor prognosis. However, if it were possible to diagnose CCA early while effective treat methods are available, CCA patients would achieve a better quality of life. Therefore, preventing the process of CCA in the early stages is an urgent problem to solve. An accurate, quick and safe method to diagnose early-stage CCA is required. The present review discusses the risk factors, status of research and certain serum markers of CCA. The sensitivity and specificity of these markers differ from each other. To explore the more accurate serum markers may be a novel direction and method for the diagnosis of CCA in laboratory medicine in the future.

Raf kinase inhibitor protein inhibits cholangiocarcinoma cell metastasis by downregulating matrix metalloproteinase 9 and upregulating tissue inhibitor of metalloproteinase 4 expression

Cholangiocarcinoma cells originate in the biliary epithelium. The cells easily metastasize and cause relapse. The effect of Raf kinase inhibitor protein (RKIP) on the biological behavior of cholangiocarcinoma cells is not yet clear. In the present study, RKIP and cytokeratin 19 expression was detected in the extrahepatic tissues of cholangiocarcinoma patients by immunohistochemistry. RKIP small interfering (si)RNA or an RKIP-overexpressing adenoviral vector were used to infect the human cholangiocarcinoma RBE cell line. RKIP protein or gene expression was analyzed by western blotting or reverse transcription-quantitative polymerase chain reaction (RT-qPCR), respectively. The cells were assayed for proliferation, apoptosis, invasion and migration. Matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase 4 (TIMP-4) mRNA was assayed by RT-qPCR. RKIP expression was reduced in the extrahepatic cholangiocarcinoma tumor compared with the adjacent uninvolved peritumoral tissues. The current study revealed that RKIP expression was positively correlated with cell differentiation, but negatively correlated with lymph node or distant metastasis (P<0.05). RKIP siRNA treatment promoted RBE cell invasion, but RKIP overexpression prevented cell invasion. In the pDC316-siRNA recombinant vector group, the cells migrated more quickly compared with the siRNA-negative control group, and in the RKIP-expressing adenoviral vector group, the cells migrated more slowly compared with the adenoviral negative control group. RKIP inhibited the invasive and metastatic ability of the cholangiocarcinoma cell line, RBE, by downregulating MMP-9 and upregulating TIMP-4 mRNA expression. RKIP is negatively associated with cholangiocarcinoma distant metastasis and prevents cholangiocarcinoma cell metastasis through downregulating MMP-9 expression and upregulating TIMP-4 expression.

Serum tumor markers in bile duct cancer--a review

CONTEXT

Bile duct cancer (BDC) is a disease with a very grave prognosis, often diagnosed too late.

OBJECTIVE

The aim of this review is to evaluate available literature on tumor markers in serum from patients with BDC.

METHODS

Using the search words "serum markers", "bile duct cancer", "cholangiocarcinoma", "biomarker" and "tumor marker", a search was carried out.

RESULTS

Seventy-five studies were included in the review.

CONCLUSION

CA19-9 is by far the most studied and most promising diagnostic and/or prognostic marker in BDC. But also the different mucins are interesting as new markers of BDC in serum.

Serum and bile NGAL for clinically distinguishing malignant biliary strictures from benign biliary strictures

AIM: To investigate the value of serum and bile neutrophil gelatinase associated lipocalin (NGAL) for distinguishing malignant strictures caused by cholangiocarcinoma (CCA) or pancreatic cancer from benign biliary strictures.

METHODS: The study was performed prospectively on patients admitted for endoscopic retrograde cholangiopancreatography biliary decompression. Forty-four patients with dilated biliary ducts, including 12 cases of CCA, 8 cases of pancreatic cancer, 1 case of carcinoma of the ampulla, and 23 cases of benign biliary strictures, were enrolled. Their sera and bile were collected to measure NGAL. Routine biochemistry including liver function test and routine blood examination was also performed. Enzyme-linked immunosorbent assay was performed to measure the contents of NGAL in serum and bile samples.

RESULTS: Serum NGAL had no significant value for discriminating malignant and benign biliary strictures (mean, 31.10 ng/mL vs 118.35 ng/mL, P = 0.0825). Biliary NGAL levels were significantly raised in the malignant disease group compared with the benign disease group (mean, 199.0 ng/mL vs 466.7 ng/mL, P = 0.0215).

CONCLUSION: Measurement of biliary NGAL, not serum NGAL, may differentiate malignant biliary strictures from benign biliary strictures.

A review of the clinical diagnosis and therapy of cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common primary hepatic malignancy worldwide. The incidence of intrahepatic CCA is increasing, whereas that of extrahepatic CCA is decreasing. This review looks at the new advances that have been made in the management of CCA, based on a PubMed and Science Citation Index search of results from randomized controlled trials, reviews, and cohort, prospective and retrospective studies. Aggressive interventional approaches and new histopathological techniques have been developed to make a histological diagnosis in patients with high risk factors or suspected CCA. Resectability of the tumour can now be assessed using multiple radiological imaging studies; the main prognostic factor after surgery is a histologically negative resection margin. Biliary drainage and/or portal vein embolization may be performed before extended radical resection, or liver transplantation may be undertaken in combination with neoadjuvant chemotherapy or chemoradiotherapy. Though many advances have been made in the management of CCA, the standard modality of treatment has not yet been established. This review focuses on the clinical options for different stages of CCA.

Intrahepatic cholangiocarcinoma: pathogenesis and rationale for molecular therapies

Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy with very poor prognosis. Genome-wide, high-throughput technologies have made major advances in understanding the molecular basis of this disease, although important mechanisms are still unclear. Recent data have revealed specific genetic mutations (for example, KRAS, IDH1 and IDH2), epigenetic silencing, aberrant signaling pathway activation (for example, interleukin (IL)-6/signal transducer and activator of transcription 3 (STAT3), tyrosine kinase receptor-related pathways) and molecular subclasses with unique alterations (for example, proliferation and inflammation subclasses). In addition, some ICCs share common genomic traits with hepatocellular carcinoma. All this information provides the basis to explore novel targeted therapies. Currently, surgery at early stage is the only effective therapy. At more advanced stages, chemotherapy regimens are emerging (that is, cisplatin plus gemcitabine), along with molecular targeted agents tested in several ongoing clinical trials. Nonetheless, a first-line conclusive treatment remains an unmet need. Similarly, there are no studies assessing tumor response related with genetic alterations. This review explores the recent advancements in the knowledge of the molecular alterations underlying ICC and the future prospects in terms of therapeutic strategies leading towards a more personalized treatment of this neoplasm.

A prospective proteomic-based study for identifying potential biomarkers for the diagnosis of cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is becoming a common fatal hepatic tumor. Early detection of CCA is hampered by the absence of a sufficiently accurate and noninvasive diagnostic test. Proteomic analysis would be a powerful tool to identify potential biomarkers of this cancer.

AIMS

This study aims to identify new protein markers that are specific for CCA using proteomic approaches and to evaluate the performance of S100 calcium-binding protein A9 (S100A9) and chaperonin-containing TCR1, subunit 3 (CCTγ) as diagnostic markers for screening test of CCA.

METHODS

Two-dimensional differential gel electrophoresis (2-D DIGE) coupled with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were used to analyze and screen biomarker candidates in the proteomes of five human CCA samples and five healthy control samples. Subsequently, two potential biomarkers, S100A9 and CCTγ, were chosen for validation and analysis by immunohistochemical methods using CCA tissue microarrays.

RESULTS

Twenty protein spots were significantly elevated and five protein spots were downregulated in all patients (p < 0.05). The positive rate was significantly higher in patients with CCA (48 ± 35%) compared with the normal liver control group (5 ± 10%, p < 0.001), the hepatocellular carcinoma group (15 ± 20%, p < 0.001), and the cirrhosis group (12 ± 16%, p < 0.001). A greater proportion of patients with CCA were positive for CCTγ (72 ± 18%) compared with the normal liver control group (43 ± 22%, p < 0.001), the hepatocellular carcinoma group (45 ± 20%, p < 0.001), and the cirrhosis group (39 ± 25%, p < 0.001).

CONCLUSIONS

Combined comparative proteomic analysis using 2-D DIGE and MALDI-TOF is an effective method for identifying differentially expressed proteins in CCA tissues. The expression of S100A9 and CCTγ showed promise as novel diagnostic markers for CCA.

Glycoproteomics-based cancer marker discovery adopting dual enrichment with Wisteria floribunda agglutinin for high specific glyco-diagnosis of cholangiocarcinoma

Cholangiocarcinoma (CC) is a lethal malignancy because it exhibits asymptomatic growth infiltrating the surrounding structures and therefore is usually detected at an advanced stage. The mainstay of treatment for CC is complete resection with negative surgical margins. Therefore, its diagnosis at a relatively early stage is demanded for performing relevant surgical resection. Since the definitive CC diagnosis depends on invasive methods such as biliary cytology and biopsy, a noninvasive assay with high diagnostic accuracy is keenly required. We therefore developed a CC marker with high specificity by the Wisteria floribunda agglutinin (WFA)-assisted glycoproteomics approach. WFA-positive glycoproteins were enriched by the direct dissection of the WFA-stained CC tissue region and following WFA-agarose column chromatography. Subsequent analysis by mass spectrometry identified 71 proteins as candidate markers. Screening of these candidates by gene expression profiling and immunohistochemistry resulted in the selection of L1 cell adhesion molecule (L1CAM) as the most specific CC marker. We confirmed the importance of WFA-positivity for L1CAM using both bile and serum of CC and benign bile duct disease patients. Specifically, WFA-positive L1CAM was enriched from serum by the WFA-assisted affinity capturing, with which CC was efficiently distinguished from benign. In the primary verification study using bile from CC patients (n=29) and that of benign bile duct disease (n=29), WFA-positive L1CAM distinguished CC with high specificity (sensitivity=0.66, specificity=0.93, overall accuracy=0.79, area under the receiver operating curve [AUC]=0.82). The combined use of the WFA-positive L1CAM assay with the high sensitive assay detecting WFA-positive sialylated mucin 1 sufficiently improved the diagnostic accuracy of CC (overall accuracy=0.84, AUC=0.93). This combination will possibly be a precise procedure for CC diagnosis compared with conventional diagnostic techniques.

BIOLOGICAL SIGNIFICANCE

In this study, we constructed the system for verification of the candidate molecules that exhibit disease specific glyco-alterations and discovered a useful CC marker by the glycoproteomics-assisted strategy for biomarker discovery. Based on the strategy, we previously found that WFA is the best probe to detect CC-specific glycosylation and WFA-positive sialyl MUC1 as a possible biomarker candidate. While the diagnostic specificity of WFA-positive sialyl MUC1 was not superb, we proposed a new biomarker candidate WFA-positive L1CAM with high specificity in bile and serum to complement the previous one. We proved that the novel combination assay of WFA-L1CAM and WFA-sialyl MUC1 selected based on our strategy has the possibility to become a reliable serological test. This study represents application of our strategy, which can be extrapolated to discovery of marker candidates for other diseases.

The challenge of cholangiocarcinoma: dissecting the molecular mechanisms of an insidious cancer

Cholangiocarcinoma is a fatal cancer of the biliary epithelium and has an incidence that is increasing worldwide. Survival beyond a year of diagnosis is less than 5%, and therapeutic options are few. Known risk factors include biliary diseases such as primary sclerosing cholangitis and parasitic infestation of the biliary tree, but most cases are not associated with any of these underlying diseases. Numerous in vitro and in vivo models, as well as novel analytical techniques for human samples, are helping to delineate the many pathways implicated in this disease, albeit at a frustratingly slow pace. As yet, however, none of these studies has been translated into improved patient outcome and, overall, the pathophysiology of cholangiocarcinoma is still poorly understood. There remains an urgent need for new approaches and models to improve management of this insidious and devastating disease. In this review, we take a bedside-to-bench approach to discussing cholangiocarcinoma and outline research opportunities for the future in this field.

Oxidized alpha-1 antitrypsin as a predictive risk marker of opisthorchiasis-associated cholangiocarcinoma

The oxidized alpha-1 antitrypsin (ox-A1AT) is one modified form of A1AT, generated via oxidation at its active site by free radicals released from inflammatory cells which subsequently are unable to inhibit protease enzymes. The presence of ox-A1AT in human serum has been used as oxidative stress indicator in many diseases. As oxidative/nitrative damage is one major contributor in opisthorchiasis-driven cholangiocarcinogenesis, we determined A1AT and ox-A1AT expression in human cholangiocarcinoma (CCA) tissue using immunohistochemical staining and measured serum ox-A1AT levels by ELISA. A1AT and ox-A1AT were found to be expressed in the tumor of CCA patients. The group with high expression has a significant poor prognosis. Serum levels of ox-A1AT were also significantly higher in groups of patients with heavy Opisthorchis viverrini infection, advanced periductal fibrosis (APF) and CCA when compared with healthy controls (P < 0.001). Odds ratio (OR) analysis implicated high ox-A1AT levels as a risk predictor for APF and CCA (P < 0.001; OR = 140.5 and 22.0, respectively). In conclusion, as APF may lead to hepatobiliary diseases and an increased risk of CCA development, our results identified ox-A1AT as a potential risk indicator for opisthorchiasis-associated CCA. This marker could now be explored for screening of subjects living in endemic areas where the prevalence of opisthorchiasis still remains high.

Expression of matrix metalloproteinase-7 is an unfavorable prognostic factor in intrahepatic cholangiocarcinoma

BACKGROUND

Intrahepatic cholangiocarcinoma (IHCC) is a highly malignant neoplasm, but the prognostic factors of IHCC are not yet fully understood. The matrix metalloproteinases (MMPs) are known to be related to tumor viability. The aim of this study was to evaluate the prognostic significance of clinicopathological and immunohistochemical characteristics of resected IHCC.

PATIENTS AND METHODS

From 1996 to 2006, we surgically treated 35 patients with IHCC. Clinicopathological and immunohistochemical characteristics, including expression of MMPs, vascular endothelial growth factor, and epidermal growth factor receptor in the resected specimens, were investigated, and overall survival rates were evaluated with regard to the characteristics using univariate and multivariate analyses.

RESULTS

Univariate analysis revealed the significant prognostic factors to be preoperative serum CEA and CA19-9, intraoperative transfusion, tumor size, surgical margin, lymph node metastasis, invasion of portal and hepatic vein, intrahepatic metastasis, UICC stage, and expression of MMP-7. Subsequent multivariate analysis indicated that MMP-7 was an independent prognostic factor (hazard ratio (HR), 4.698; 95% confidence interval (CI), 0.057-0.866; P = 0.03) along with intrahepatic metastasis (HR, 5.694; 95% CI, 0.029-0.706; P = 0.017).

CONCLUSION

MMP-7 expression is associated with a poor prognosis in patients with resected IHCC.

The role of cancer-associated myofibroblasts in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma is typically characterized by a dense desmoplastic stroma, of which cancer-associated myofibroblasts (which express α-smooth muscle actin), are a major cellular component. These stromal myofibroblasts have a crucial role in accelerating the progression of intrahepatic cholangiocarcinoma and in promoting resistance to therapy through interactive autocrine and paracrine signaling pathways that promote malignant cell proliferation, migration, invasiveness, apoptosis resistance and/or epithelial-mesenchymal transition. These changes correlate with aggressive tumor behavior. Hypoxic desmoplasia and aberrant Hedgehog signaling between stromal myofibroblastic cells and cholangiocarcinoma cells are also critical modulators of intrahepatic cholangiocarcinoma progression and therapy resistance. A novel strategy has been developed to achieve improved therapeutic outcomes in patients with advanced intrahepatic cholangiocarcinoma, based on targeting of multiple interactive pathways between cancer-associated myofibroblasts and intrahepatic cholangiocarcinoma cells that are associated with disease progression and poor survival. Unique organotypic cell culture and orthotopic rat models of cholangiocarcinoma progression are well suited to the rapid preclinical testing of this potentially paradigm-shifting strategy.

The role of cancer-associated myofibroblasts in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma is typically characterized by a dense desmoplastic stroma, of which cancer-associated myofibroblasts (which express α-smooth muscle actin), are a major cellular component. These stromal myofibroblasts have a crucial role in accelerating the progression of intrahepatic cholangiocarcinoma and in promoting resistance to therapy through interactive autocrine and paracrine signaling pathways that promote malignant cell proliferation, migration, invasiveness, apoptosis resistance and/or epithelial-mesenchymal transition. These changes correlate with aggressive tumor behavior. Hypoxic desmoplasia and aberrant Hedgehog signaling between stromal myofibroblastic cells and cholangiocarcinoma cells are also critical modulators of intrahepatic cholangiocarcinoma progression and therapy resistance. A novel strategy has been developed to achieve improved therapeutic outcomes in patients with advanced intrahepatic cholangiocarcinoma, based on targeting of multiple interactive pathways between cancer-associated myofibroblasts and intrahepatic cholangiocarcinoma cells that are associated with disease progression and poor survival. Unique organotypic cell culture and orthotopic rat models of cholangiocarcinoma progression are well suited to the rapid preclinical testing of this potentially paradigm-shifting strategy.

Plasma hydroxyproline, MMP-7 and collagen I as novel predictive risk markers of hepatobiliary disease-associated cholangiocarcinoma

Chronic opisthorchiasis caused by Opisthorchis viverrini infection is characterized by advanced periductal fibrosis leading to hepatobiliary diseases (HBD), including cholangiocarcinoma (CCA). We aimed to determine fibrotic markers to differentiate HBD status including opisthorchiasis, benign biliary disease (BBD) and CCA. Candidate fibrotic markers in plasma of healthy individuals (n = 14) and patients with opisthorchiasis (n = 32, pre- and post-treatment with praziquantel), BBD (n = 31), CCA (n = 37) and other types of tumors (n = 14) were measured by ELISA and zymography. Plasma levels of hydroxyproline (HYP), collagen I, MMP-7 and TIMP2 in opisthorchiasis patients were significantly higher than those in healthy individuals, and MMP9/TIMP2 balance may be associated with tissue resorption after praziquantel treatment. HYP and TIMP-2 levels were significantly correlated with periductal fibrosis status evaluated by ultrasonography. Plasma HYP level of CCA patients was the highest among HBD patients (p < 0.05). ROC curves revealed HYP, MMP-7 and collagen I levels significantly distinguished opisthorchiasis, BBD and CCA (p < 0.001). Odd ratio (OR) analysis demonstrated these markers in opisthorchiasis were predictable for BBD risk (p < 0.05; OR = 28.50, 10.12 and 4.63 for collagen I, MMP-7 and HYP, respectively), and the risk was reduced by praziquantel treatment. Interestingly, only plasma HYP level in BBD was predictable for CCA risk (OR = 3.69; p = 0.020). In conclusion, plasma HYP, collagen I and MMP-7 may be useful as novel predictive markers of opisthorchiasis-related BBD, and HYP may be used as a diagnostic marker for CCA.

Bilirubin levels predict malignancy in patients with obstructive jaundice

BACKGROUND

Differentiating between benign and malignant causes of obstructive jaundice can be challenging, even with the advanced imaging and endoscopic techniques currently available. In patients with obstructive jaundice, the predictive accuracy of bilirubin levels at presentation was examined in order to determine whether such data could be used to differentiate between malignant and benign disease.

METHODS

A total of 1,026 patients with obstructive jaundice were identified. Patients were divided into benign and malignant groups. The benign patients were subgrouped into those with choledocholithiasis and those with inflammatory strictures of the biliary tree. Bilirubin levels at presentation and other demographic data were obtained from case records.

RESULTS

Area under the curve (AUC) values for bilirubin as a predictor of malignancy were highly significant for all benign presentations and for those with benign biliary strictures (AUC: 0.8 for both groups; P < 0.001). A bilirubin level > 100 µmol/l was determined to provide the optimum sensitivity and specificity for malignancy in all patients and in those without choledocholithiasis (71.9% and 86.9%, 71.9% and 88.0%, respectively). The application of a bilirubin level > 250 µmol/l achieved specificities of 97.1% and 98.0% in each subgroup of patients, respectively.

CONCLUSIONS

In patients with obstructive jaundice, bilirubin levels in isolation represent an important tool for discriminating between benign and malignant underlying causes.

A systematic analysis of the effects of increasing degrees of serum immunodepletion in terms of depth of coverage and other key aspects in top-down and bottom-up proteomic analyses

Immunodepletion of clinical fluids to overcome the dominance by a few very abundant proteins has been explored but studies are few, commonly examining only limited aspects with one analytical platform. We have systematically compared immunodepletion of 6, 14, or 20 proteins using serum from renal transplant patients, analysing reproducibility, depth of coverage, efficiency, and specificity using 2-D DIGE (‘top-down’) and LC-MS/MS (‘bottom-up’). A progressive increase in protein number (≥2 unique peptides) was found from 159 in unfractionated serum to 301 following 20 protein depletion using a relatively high-throughput 1-D-LC-MS/MS approach, including known biomarkers and moderate–lower abundance proteins such as NGAL and cytokine/growth factor receptors. On the contrary, readout by 2-D DIGE demonstrated good reproducibility of immunodepletion, but additional proteins seen tended to be isoforms of existing proteins. Depletion of 14 or 20 proteins followed by LC-MS/MS showed excellent reproducibility of proteins detected and a significant overlap between columns. Using label-free analysis, greater run-to-run variability was seen with the Prot20 column compared with the MARS14 column (median %CVs of 30.9 versus 18.2%, respectively) and a corresponding wider precision profile for the Prot20. These results illustrate the potential of immunodepletion followed by 1-D nano-LC-LTQ Orbitrap Velos analysis in a moderate through-put biomarker discovery process.

Markers of bile duct tumors

Biliary tract carcinomas are relatively rare, representing less than 1% of cancers. However, their incidence has increased in Japan and in industrialized countries like the USA. Biliary tract tumors have a poor prognosis and a high mortality rate because they are usually detected late in the course of the disease; therapeutic treatment options are often limited and of minimal utility. Recent studies have shown the importance of serum and molecular markers in the diagnosis and follow up of biliary tract tumors. This review aims to introduce the main features of the most important serum and molecular markers of biliary tree tumors. Some considerable tumor markers are cancer antigen 125, carbohydrate antigen 19-9, carcinoembryonic antigen, chromogranin A, mucin 1, mucin 5, alpha-fetoprotein, claudins and cytokeratins.