Pathogenesis, diagnosis, and management of cholangiocarcinoma

Improve bile duct-targeted drug delivery and therapeutic efficacy for cholangiocarcinoma by cucurbitacin B loaded phospholipid complex modified with berberine hydrochloride

In present study, a novel phospholipid complex loaded cucurbitacin B modified with berberine hydrochloride (CUB-PLC-BER) was prepared by a simple solvent evaporation method with the aim of improving bile duct-targeted drug delivery and therapeutic efficacy for cholangiocarcinoma (CC). The complex's physicochemical properties were systemically investigated in terms of scanning electron microscopy (SEM), x-ray diffraction (XRD) and infrared absorption spectroscopy (IR). In vivo and in vitro antitumor studies, CUB-PLC-BER and the unmodified cucurbitacin B-phospholipid complex (CUB-PLC) presented stronger antitumor efficacy against human cholangiocarcinoma cells (QBC939 cells) than free cucurbitacin B (CUB), while phospholipids (PL) itself had no significant toxicity. Besides that, CUB-PLC showed the advantage over the free CUB and CUB-PLC-BER with regard to the inhibition of tumor growth in vivo antitumor study. Failure to establish the orthotopic CC model, the study attempted to measure the level of CUB in plasma and in bile to explore bile duct-targeted effect indirectly. In the pharmacokinetics study in rats, the average values of Cmax and AUC0-8h of CUB-PLC-BER group in rat bile were higher than those of CUB-PLC, while an opposite result was found in plasma. Meanwhile, the Cmax, AUC0-8h and AUC0-24h of CUB were the least both in plasma and in bile. The results indicated that the CUB-PLC-BER tended to provide a high and prolonged drug concentration to bile duct, and PL played a central role in internalizing CUB into cells to improve the water insoluble drug's permeability, which was of great benefit to enhance the bioavailability of CUB and improve therapeutic efficacy of CC. These results elucidated the potential of CUB-PLC-BER as drug delivery system for improving bile duct-targeted and therapeutic efficacy for CC.

Endoscopic diagnosis of cholangiocarcinoma: From endoscopic retrograde cholangiography to bile proteomics

Cholangiocarcinoma (CCA) is the second most common primary liver cancer. In clinical practice, the diagnosis remains challenging and often requires endoscopic approaches. Endoscopic retrograde and percutaneous transhepatic cholangiography are the first-line endoscopic procedures for the evaluation of indeterminate bile duct strictures. Tissue acquisition via brush cytology and forceps biopsies allows the cytological and/or histological confirmation of the disease. Due to the low sensitivity of these techniques, repetitive examinations and/or alternative approaches are required. Cholangioscopy, endoscopic and intraductal ultrasound and confocal laser endomicroscopy are additional methods which can be applied for the diagnosis of CCA. Particularly, new experimental approaches like bile and urine proteomic analyses show promising results which have to be evaluated prospectively for further integration in diagnostic algorithms.

Role of 5-hydroxymethylcytosine level in diagnosis and prognosis prediction of intrahepatic cholangiocarcinoma

The loss of 5-hydroxymethylcytosine (5-hmC) has been identified as an epigenetic hallmark in several malignancies. However, its role in intrahepatic cholangiocarcinoma (ICC) is still unknown. Our study aims to investigate the level of 5-hmC in diagnosis and prognosis prediction of ICC. The 5-hmC levels were detected using dot blot, tissue microarray technique and immunohistochemical method, and the correlation between 5-hmC level and ICC clinicopathological parameters was analysed. Compared with matched liver tissues, most of ICC tissues presented with the loss of 5-hmC. Furthermore, the subgroups of cirrhotic and poor differentiation tissues showed the lowest level of 5-hmC. We found that 5-hmC level in non-elevated ICC patients was significantly related to lymph node metastasis and TNM stage and not related to vessel invasion, sex, age, HBV, cirrhosis or degree of differentiation. ICC patients with high TNM stage (stages III and IV) and lymph node metastases had significantly lower 5-hmC level than those with low TNM stage (stages I and II) and no lymph node metastases. Further analysis showed that low 5-hmC level is significantly correlated with worse overall survival (OS) and disease-free survival (DFS). Importantly, multivariate analysis indicated that 5-hmC level, tumour diameter, lymphatic metastasis and tumour differentiation could be used as independent prognostic factors for ICC. The loss of 5-hmC is implicated in the progression of ICC. Our results can contribute to the diagnostic ability and postoperative surveillance of ICC patients.

Liver cancer: Approaching a personalized care

The knowledge and understanding of all aspects of liver cancer [this including hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA)] have experienced a major improvement in the last decades. New laboratory technologies have identified several molecular abnormalities that, at the very end, should provide an accurate stratification and optimal treatment of patients diagnosed with liver cancer. The seminal discovery of the TP53 hotspot mutation [1 ,2 ] was an initial landmark step for the future classification and treatment decision using conventional clinical criteria blended with molecular data. At the same time, the development of ultrasound, computed tomography (CT) and magnetic resonance (MR) has been instrumental for earlier diagnosis, accurate staging and treatment advances. Several treatment options with proven survival benefit if properly applied are now available. Major highlights include: i) acceptance of liver transplantation for HCC if within the Milan criteria [3 ], ii) recognition of ablation as a potentially curative option [4 ,5 ], iii) proof of benefit of chemoembolization (TACE), [6 ] and iv) incorporation of sorafenib as an effective systemic therapy [7 ]. These options are part of the widely endorsed BCLC staging and treatment model (Fig. 1 ) [8 ,9 ]. This is clinically useful and it will certainly keep evolving to accommodate new scientific evidence.

This review summarises the data which are the basis for the current recommendations for clinical practice, while simultaneously exposes the areas where more research is needed to fulfil the still unmet needs (Table 1 ).

Epidemiology of cholangiocarcinoma

Cholangiocarcinoma (CCA) is a cancer arising from the intra- or extrahepatic bile ducts and mainly characterized by its late diagnosis and fatal outcome. CCA is the second most common primary liver tumour and accounts for approximately 10-15% of all hepatobiliary malignancies. The development of CCA is linked to a wide spectrum of conditions causing biliary inflammation, cholestasis and inflammation of the liver. The geographic diversity of risk factors is reflected in considerable differences in incidence worldwide. Although data are not consistent, incidence seems to be rising in the Western World. Given the limited opportunities of treating advanced CCA, surveillance has been suggested as a strategy for detection of early disease in the high-risk group of patients with primary sclerosing cholangitis (PSC). In this review we present an updated overview of the epidemiology of CCA. We also highlight the risk of CCA in PSC with special focus on surveillance strategies.

Negative impact of preoperative platelet-lymphocyte ratio on outcome after hepatic resection for intrahepatic cholangiocarcinoma

The elevated platelet-to-lymphocyte ratio (PLR), determined using an easy blood test based on platelet and lymphocyte counts, is reported to be a predictor of poor survival in patients with several cancers. The prognostic role of preoperative PLR in patients with intrahepatic cholangiocarcinoma (ICC) has, until now, been rarely investigated. The purpose of our study was to evaluate the prognostic significance of PLR in a large cohort of ICC patients after hepatic resection. We obtained data from 322 consecutive nonmetastatic ICC patients who underwent hepatectomy without preoperative therapy between 2005 and 2011. Clinicopathological parameters, including PLR, were evaluated. Overall survival (OS) and recurrence-free survival (RFS) were assessed using the Kaplan-Meier method. Using multivariate Cox regression models, the independent prognostic value of preoperative PLR was determined. Our results showed that PLR represents an independent adverse prognostic factor for OS and RFS in ICC patients using univariate and multivariate analyses. The optimal PLR cutoff value was 123 using receiver operating curve analyses. The 5-year OS and RFS rates after hepatectomy were 30.3% and 28.9% for the group with PLR 123 greater, compared with 46.2% and 39.4% for the group with PLR less than 123 (P = 0.0058 and 0.0153, respectively). In addition, high PLR values were associated with tumor size (P = 0.020). Our results suggest that preoperative PLR might represent a novel independent prognostic factor for OS and RFS in ICC patients with hepatic resection.

Pathogenesis of cholangiocarcinoma: From genetics to signalling pathways

Cholangiocarcinoma (CCA) is a malignant tumour of bile duct epithelial cells with dismal prognosis and rising incidence. Chronic inflammation resulting from liver fluke infection, hepatitis and other inflammatory bowel diseases is a major contributing factor to cholangiocarcinogenesis, likely through accumulation of serial genetic and epigenetic alterations resulting in aberration of oncogenes and tumour suppressors. Recent studies making use of advances in high-throughput genomics have revealed the genetic landscape of CCA, greatly increasing our understanding of its underlying biology. A series of highly recurrent mutations in genes such as TP53, KRAS, SMAD4, BRAF, MLL3, ARID1A, PBRM1 and BAP1, which are known to be involved in cell cycle control, cell signalling pathways and chromatin dynamics, have led to investigations of their roles, through molecular to mouse modelling studies, in cholangiocarcinogenesis. This review focuses on the landscape genetic alterations in CCA and its functional relevance to the formation and progression of CCA.

Patterns of chromosomal copy-number alterations in intrahepatic cholangiocarcinoma

Background

Intrahepatic cholangiocarcinomas (ICC) are relatively rare malignant tumors associated with a poor prognosis. Recent studies using genome-wide sequencing technologies have mainly focused on identifying new driver mutations. There is nevertheless a need to investigate the spectrum of copy number aberrations in order to identify potential target genes in the altered chromosomal regions. The aim of this study was to characterize the patterns of chromosomal copy-number alterations (CNAs) in ICC.

Methods

53 patients having ICC with frozen material were selected. In 47 cases, DNA hybridization has been performed on a genomewide SNP array. A procedure with a segmentation step and a calling step classified genomic regions into copy-number aberration states. We identified the exclusively amplified and deleted recurrent genomic areas. These areas are those showing the highest estimated propensity level for copy loss (resp. copy gain) together with the lowest level for copy gain (resp. copy loss). We investigated ICC clustering. We analyzed the relationships between CNAs and clinico-pathological characteristics.

Results

The overall genomic profile of ICC showed many alterations with higher rates for the deletions. Exclusively deleted genomic areas were 1p, 3p and 14q. The main exclusively amplified genomic areas were 1q, 7p, 7q and 8q. Based on the exclusively deleted/amplified genomic areas, a clustering analysis identified three tumors groups: the first group characterized by copy loss of 1p and copy gain of 7p, the second group characterized by 1p and 3p copy losses without 7p copy gain, the last group characterized mainly by very few CNAs. From univariate analyses, the number of tumors, the size of the largest tumor and the stage were significantly associated with shorter time recurrence. We found no relationship between the number of altered cytobands or tumor groups and time to recurrence.

Conclusion

This study describes the spectrum of chromosomal aberrations across the whole genome. Some of the recurrent exclusive CNAs harbor candidate target genes. Despite the absence of correlation between CNAs and clinico-pathological characteristics, the co-occurence of 7p gain and 1p loss in a subgroup of patients may suggest a differential activation of EGFR and its downstream pathways, which may have a potential effect on targeted therapies.

Enhanced expression of suppresser of cytokine signaling 3 inhibits the IL-6-induced epithelial-to-mesenchymal transition and cholangiocarcinoma cell metastasis

It was recently demonstrated that interleukin-6 (IL-6) induces the epithelial-to-mesenchymal transition (EMT) in cholangiocarcinoma (CCA), but the underlying molecular mechanism remains to be explored. In this study, we studied the role of suppresser of cytokine signaling 3 (SOCS3), a negative feedback regulator of IL-6/STAT3, in the IL-6-induced EMT in CCA. Treatment with IL-6 induced the EMT by decreasing the E-cadherin expression and increasing the expression of N-cadherin and vimentin. Using wound healing and invasion assays, we found that IL-6 promoted cell motility. Further, a stably transfected cell line overexpressing SOCS3 was constructed. Enhanced SOCS3 expression decreased IL-6-induced cell invasion and EMT in parallel with downregulating the IL-6/STAT3 pathway. In contrast, SOCS3 silencing using siRNA exhibited no effect on the cell invasive ability and EMT. Finally, an in vivo study indicated that the enhancement of SOCS3 expression decreased metastasis compared with the control, and this effect was achieved by the repression of p-STAT3, N-cadherin and vimentin, and the induction of E-cadherin assessed by Western blot analysis. Our results suggest that enhanced expression of SOCS3 can antagonize IL-6-induced EMT and cell metastasis by abrogating the IL-6/STAT3 pathway. These data establish that SOCS3 plays a role in the EMT in CCA and may provide novel therapeutic strategies for CCA.

Hepatic inflammation and fibrosis: functional links and key pathways

Inflammation is one of the most characteristic features of chronic liver disease of viral, alcoholic, fatty, and autoimmune origin. Inflammation is typically present in all disease stages and associated with the development of fibrosis, cirrhosis, and hepatocellular carcinoma. In the past decade, numerous studies have contributed to improved understanding of the links between hepatic inflammation and fibrosis. Here, we review mechanisms that link inflammation with the development of liver fibrosis, focusing on the role of inflammatory mediators in hepatic stellate cell (HSC) activation and HSC survival during fibrogenesis and fibrosis regression. We will summarize the contributions of different inflammatory cells, including hepatic macrophages, T and B lymphocytes, natural killer cells and platelets, as well as key effectors, such as cytokines, chemokines, and damage-associated molecular patterns. Furthermore, we will discuss the relevance of inflammatory signaling pathways for clinical liver disease and for the development of antifibrogenic strategies.

Risk factors for perihilar cholangiocarcinoma: a hospital-based case-control study

BACKGROUND & AIMS

Perihilar cholangiocarcinoma (pCCA) is the most common form of bile duct cancer, arising from cholangiocytes at the confluence of hepatic ducts. Given the diversity of cholangiocarcinoma (CCA) aetiology according to the location, and the scarcity of studies on the aetiology of pCCA, we aimed to identify the risk factors for pCCA.

METHODS

A total of 81 patients diagnosed with pCCA between July 2007 and December 2013, and 162 controls matched 2:1 for age, sex and date of diagnosis were included in this hospital-based case-control study. Potential risk factors were retrospectively investigated through clinical records, and the associations with pCCA were studied by calculating the odds ratios (ORs) using conditional logistic regression analysis.

RESULTS

In the univariate model, the prevalence of choledocholithiasis (OR: 14.00, P = 0.014), hepatolithiasis (OR: 12.00, P = 0.021) and diabetes mellitus (DM) (OR: 2.74, P = 0.005) was higher in pCCA patients than in controls. Heavy smoking and cirrhosis were marginally significant risk factors for pCCA (P < 0.1). Multivariate analysis revealed an association between pCCA and hepatolithiasis, choledocholithiasis, DM, and heavy smoking, each, with adjusted ORs of 16.47, 9.39, 3.36 and 2.52 respectively. DM, heavy smoking, hepatolithiasis and choledocholithiasis accounted for about 22.5%, 17.1%, 8.5% and 4.8% of pCCA risk respectively (population attributable risk percentage).

CONCLUSION

Our data showed that DM, heavy smoking, choledocholithiasis and hepatolithiasis were risk factors for pCCA development, implying that pCCA may share some aetiological factors with intrahepatic CCA although it has been classified as extrahepatic CCA.

Differentially expressed gene profiles of intrahepatic cholangiocarcinoma, hepatocellular carcinoma, and combined hepatocellular-cholangiocarcinoma by integrated microarray analysis

Intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC) are common primary liver cancers worldwide. However, the survival and prognosis of ICC are much poorer than those of HCC, indicating the different molecular characteristics and mechanisms between ICC and HCC. To identify differentially expressed (DE) genes between ICC and HCC or combined hepatocellular-cholangiocarcinoma (CHC), we performed integrated analysis of publicly available microarray Gene Expression Omnibus (GEO) datasets by MetaOmics. Three GEO datasets comprising 32 ICC biochips, 77 HCC biochips, and 34 CHC biochips were available for the data integration. We identified 7313 DE genes between ICC and HCC, including 3650 upregulated genes and 3663 downregulated genes. The S100 family members on chromosome 1q21 were extensively upregulated in ICC, and S100A11 had the greatest degree of upregulation in ICC. Based on the DE genes, combined gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis showed the enhanced pathways of local adhesion, ECM-receptor interaction, and regulation of action cytoskeleton, suggesting the enhanced communication between ICC and the microenvironment. Additionally, development-related genes and development-related pathways, including the Notch, Wnt, and TGF-β signaling pathways, were shown to be active prominently in ICC. Taken together, we identified the characteristically upregulated or downregulated DE genes and pathways in ICC compared with HCC or CHC. These DE genes and pathways supply new transcriptomics evidence for ICC and could help identify new therapeutic targets.

Recent advances in the development of farnesoid X receptor agonists

Farnesoid X receptors (FXRs) are nuclear hormone receptors expressed in high amounts in body tissues that participate in bilirubin metabolism including the liver, intestines, and kidneys. Bile acids (BAs) are the natural ligands of the FXRs. FXRs regulate the expression of the gene encoding for cholesterol 7 alpha-hydroxylase, which is the rate-limiting enzyme in BA synthesis. In addition, FXRs play a critical role in carbohydrate and lipid metabolism and regulation of insulin sensitivity. FXRs also modulate live growth and regeneration during liver injury. Preclinical studies have shown that FXR activation protects against cholestasis-induced liver injury. Moreover, FXR activation protects against fatty liver injury in animal models of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), and improved hyperlipidemia, glucose intolerance, and insulin sensitivity. Obeticholic acid (OCA), a 6α-ethyl derivative of the natural human BA chenodeoxycholic acid (CDCA) is the first-in-class selective FXR agonist that is ~100-fold more potent than CDCA. Preliminary human clinical trials have shown that OCA is safe and effective. In a phase II clinical trial, administration of OCA was well-tolerated, increased insulin sensitivity and reduced markers of liver inflammation and fibrosis in patients with type II diabetes mellitus and NAFLD. In two clinical trials of OCA in patients with primary biliary cirrhosis (PBC), a progressive cholestatic liver disease, OCA significantly reduced serum alkaline phosphatase (ALP) levels, an important disease marker that correlates well with clinical outcomes of patients with PBC. Together, these studies suggest that FXR agonists could potentially be used as therapeutic tools in patients suffering from nonalcoholic fatty and cholestatic liver diseases. Larger and Longer-term studies are currently ongoing.

Recent advances in the development of farnesoid X receptor agonists

Farnesoid X receptors (FXRs) are nuclear hormone receptors expressed in high amounts in body tissues that participate in bilirubin metabolism including the liver, intestines, and kidneys. Bile acids (BAs) are the natural ligands of the FXRs. FXRs regulate the expression of the gene encoding for cholesterol 7 alpha-hydroxylase, which is the rate-limiting enzyme in BA synthesis. In addition, FXRs play a critical role in carbohydrate and lipid metabolism and regulation of insulin sensitivity. FXRs also modulate live growth and regeneration during liver injury. Preclinical studies have shown that FXR activation protects against cholestasis-induced liver injury. Moreover, FXR activation protects against fatty liver injury in animal models of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), and improved hyperlipidemia, glucose intolerance, and insulin sensitivity. Obeticholic acid (OCA), a 6α-ethyl derivative of the natural human BA chenodeoxycholic acid (CDCA) is the first-in-class selective FXR agonist that is ~100-fold more potent than CDCA. Preliminary human clinical trials have shown that OCA is safe and effective. In a phase II clinical trial, administration of OCA was well-tolerated, increased insulin sensitivity and reduced markers of liver inflammation and fibrosis in patients with type II diabetes mellitus and NAFLD. In two clinical trials of OCA in patients with primary biliary cirrhosis (PBC), a progressive cholestatic liver disease, OCA significantly reduced serum alkaline phosphatase (ALP) levels, an important disease marker that correlates well with clinical outcomes of patients with PBC. Together, these studies suggest that FXR agonists could potentially be used as therapeutic tools in patients suffering from nonalcoholic fatty and cholestatic liver diseases. Larger and Longer-term studies are currently ongoing.

Incidence of subsequent cholangiocarcinomas after another malignancy: trends in a population-based study

Cholangiocarcinoma (CCA) characterized by late diagnosis and poor outcomes represents the commonest malignancy of biliary tract. Understanding metachronous cancer associations may achieve earlier detection. We aimed to evaluate the risk of subsequent CCAs among common cancer survivors. The National Cancer Institute's Surveillance, Epidemiology, and End Results database (1973-2010) was reviewed for patients with 1 of the 25 primary cancers. Standardized incidence ratios (SIRs) were calculated as an approximation of relative risk for subsequent CCAs after primary malignancy. Data were stratified by age at primary cancer diagnosis, latency period, and application of radiation. A total of 1487 patients developed subsequent CCAs. For patients diagnosed with primary cancers between the ages 20 and 39 years, the risk was increased among colon (SIR 14.65), gallbladder (129.29), and uterus (7.29) cancer survivors. At ages of 40 to 59 years, oral cavity and pharynx (1.89), stomach (3.24), colon (1.76), gallbladder (11.78), and lung cancers (1.75) were associated with increased risk. We found persistently elevated SIRs after colon and gallbladder cancer between ages 60 and 79 years. The SIR remained significant among gallbladder cancer survivors diagnosed after 80 years. Gallbladder cancer showed elevated risk at all of the latency periods except first 6 to 11 months. Increased risk of lung cancer (1.66) was detected after 120 months. However, radiation therapy did not contribute to increased risk. This population-based study suggests that several initial cancers are associated with elevated risk of CCA. The increased risk may be due to shared genetic or environmental etiological factors between these malignancies. Lower threshold for CCA surveillance may be warranted in high-risk patients.

Association of downregulation of WWOX with poor prognosis in patients with intrahepatic cholangiocarcinoma after curative resection

BACKGROUND AND AIM

Downregulation of the WW domain containing oxidoreductase (WWOX) has been reported to be involved in tumorigenesis in several neoplasms. This study sought to investigate the expression and role of WWOX in intrahepatic cholangiocarcinoma (ICC).

METHODS

WWOX expression was measured by quantitative real-time polymerase chain reaction (PCR), immunoblot, immunofluorescence, and immunohistochemistry. The prognostic significance was assessed by Kaplan-Meier and Cox regression analyses. The role of WWOX in proliferation, anchorage-independent growth, gene expression regulation, and tumorigenesis was assessed by WWOX re-expression using lentivirus. Methylation-specific PCR was performed to evaluate the methylation status of the WWOX gene regulatory region. A DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (AZA), was used to activate the endogenous WWOX gene in ICC cells both in vitro and in vivo.

RESULTS

The expression of WWOX in ICC tissues was much lower than that in nontumorous samples and showed reverse correlation with proliferative status. Restoration of WWOX expression resulted in suppression of the growth of WWOX-deficient ICC cells through activation of the intrinsic apoptotic signaling pathway, but did not affect growth of WWOX-sufficient human intrahepatic biliary epithelial derived non-cancer cells. Multivariate analyses revealed that downregulation of WWOX was an unfavorable predictor for overall survival and cumulative recurrence rates. The WWOX gene regulatory region was frequently methylated in ICC tissues and cell lines, and intratumoral WWOX restoration, through AZA injection, suppressed tumor growth in nude mice.

CONCLUSION

Downregulation of WWOX may occur as a result of hypermethylation and implies a poor prognosis in ICC; WWOX re-expression may be a potential molecular therapeutic target for ICC.

Biliary multifocal chromosomal polysomy and cholangiocarcinoma in primary sclerosing cholangitis

OBJECTIVES

Polysomy detected by fluorescence in situ hybridization (FISH) is associated with cholangiocarcinoma (CCA) in patients with primary sclerosing cholangitis (PSC). However, a subset of PSC patients with polysomy do not manifest CCA even after long-term follow-up. It is unknown if patients with chromosomal gains detected by FISH in multiple areas of the biliary tree (i.e., multifocal polysomy, MFP) are more likely to be diagnosed with CCA than patients with unifocal polysomy (UFP). Therefore, our aim is to determine whether patients with MFP are more likely to manifest CCA compared with patients with other chromosomal abnormalities including UFP and other FISH subtypes.

METHODS

We performed a retrospective review of PSC patients without a mass lesion who underwent FISH testing at our institution from 1 January 2005 to 1 July 2013.

RESULTS

Three-hundred and seventy-one PSC patients were included. Compared with patients with UFP, those with MFP were more likely to have weight loss (32 vs. 9%), suspicious cytology (45 vs. 13%) and develop serial polysomy (91 vs. 35%). MFP was associated with CCA (hazard ratio (HR), 82.42; 95% confidence interval (CI), 24.50-277.31) and was the strongest predictor of cancer diagnosis. Suspicious cytology (HR, 26.31; 95% CI, 8.63-80.24) and UFP (HR, 13.27; 95% CI, 3.32-53.08) were also predictive of CCA. MFP, UFP and suspicious cytology remained associated with CCA in the multivariable model.

CONCLUSIONS

Compared with other FISH subtypes, MFP is the strongest predictor of CCA. However, patients with UFP and suspicious cytology (regardless of FISH status) are also at an increased risk for CCA.

Challenges to liver transplantation and strategies to improve outcomes

Liver transplantation (LT) is a highly successful treatment for many patients with nonmalignant and malignant liver diseases. However, there is a worldwide shortage of available organs; many patients deteriorate or die while on waiting lists. We review the important clinical challenges to LT and the best use of the scarce organs. We focus on changes in indications for LT and discuss scoring systems to best match donors with recipients and optimize outcomes, particularly for the sickest patients. We also cover controversial guidelines for the use of LT in patients with hepatocellular carcinoma and cholangiocarcinoma. Strategies to increase the number of functional donor organs involve techniques to perfuse the organs before implantation. Partial LT (living donor and split liver transplantation) techniques might help to overcome organ shortages, and we discuss small-for-size syndrome. Many new developments could increase the success of this procedure, which is already one of the major achievements in medicine during the second part of the 20th century.

Endoscopic ablation therapy for biliopancreatic malignancies

Biliopancreatic malignancies such as cholangiocarcinoma (CCA) has notoriously been diagnosed late. As such most therapy have been palliative in nature. Cholangioscopy allows for an earlier diagnosis to be made. Brachytherapy with the insertion of catheter with iridium-132 seeds, percutaneously or through endoscopic retrograde cholangiopancreatography (ERCP) was the earliest ablative techniques used. It has been shown to have a beneficial effect only in prolonging survival. Photodynamic therapy (PDT) has also been used for several years. stenting with PDT versus stenting alone for unresectable CCA showed a marked survival benefit with the addition of PDT. However the most exciting endoscopic ablative modality appears to be intraductal radiofrequency ablation using the Habib catheter and device. Several case series have shown the effectiveness of this technique in ablating tumors. This technique is evolving and coupled with early diagnosis of CCA through cholangioscopy will allow for a curative therapy. The crux to the effective treatment of early cancerous lesions in the bile or pancreatic duct is the early diagnosis of such lesions. Effective endoscopic ablative therapy is now available with the advent of radiofrequency ablation probes that can be passed through the duodenoscope via ERCP.

Massive parallel sequencing uncovers actionable FGFR2-PPHLN1 fusion and ARAF mutations in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is a fatal bile duct cancer with dismal prognosis and limited therapeutic options. By performing RNA- and exome-sequencing analyses, we report a novel fusion event, FGFR2-PPHLN1 (16%), and damaging mutations in the ARAF oncogene (11%). Here we demonstrate that the chromosomal translocation t(10;12)(q26;q12) leading to FGFR2-PPHLN1 fusion possesses transforming and oncogenic activity, which is successfully inhibited by a selective FGFR2 inhibitor in vitro. Among the ARAF mutations, N217I and G322S lead to activation of the pathway and N217I shows oncogenic potential in vitro. Screening of a cohort of 107 iCCA patients reveals that FGFR2 fusions represent the most recurrent targetable alteration (45%, 17/107), while they are rarely present in other primary liver tumours (0/100 of hepatocellular carcinoma (HCC); 1/21 of mixed iCCA-HCC). Taken together, around 70% of iCCA patients harbour at least one actionable molecular alteration (FGFR2 fusions, IDH1/2, ARAF, KRAS, BRAF and FGF19) that is amenable for therapeutic targeting.

Impact of microenvironment and stem-like plasticity in cholangiocarcinoma: molecular networks and biological concepts

Clinical complexity, anatomic diversity and molecular heterogeneity of cholangiocarcinoma (CCA) represent a major challenge in the assessment of effective targeted therapies. Molecular and cellular mechanisms underlying the diversity of CCA growth patterns remain a key issue of clinical concern. Crucial questions comprise the nature of the CCA-origin, the initial target for cellular transformation as well as the relationship with the cancer stem cells (CSC) concept. Additionally, since CCA often develops in the context of an inflammatory milieu (cirrhosis and cholangitis), the stromal compartment or tumour microenvironment (TME) likely promotes initiation and progression of this malignancy, contributing to its heterogeneity. This review will emphasize the dynamic interplay between stem-like intrinsic and TME-extrinsic pathways, which may represent novel options for multi-targeted therapies in CCA.

[View on the problem of Klatskin tumor]

Klatskin tumor arises from the common hepatic duct and its bifurcation the bile ducts and is the most common primary malignancy of the biliary tree. the location of the tumor and its close relationship with vascular structures at the hepatic hilum have resulted in a low resectability and high morbidity and mortality. Improvement of instrumental diagnostics and operative techniques allows to perform extended resection and complex interventions on the liver, bile ducts and vascular structures at the hepatic hilum. The role of chemoratiotherapy and photodynamic therapy is not fully understood. thus, questions of treatment and prognosis of the disease are remain relevant and require further study.

Efficacy and safety of gemcitabine-based chemotherapies in biliary tract cancer: A meta-analysis

AIM: To investigate the efficacy and safety of gemcitabine (Gem)-based combination chemotherapies for the treatment of advanced biliary tract cancer.

METHODS: Clinical trials were identified by searching scientific literature databases (PubMed, EMBASE and the Cochrane Library) for studies published between 1975 and 2013. Two reviewers independently evaluated the relevant studies and manually searched references from these reports to locate additional eligible studies. The disease response and control rates, progression-free and overall survivals, and the grade 3-4 toxicities were evaluated by a meta-analysis. Odds-ratios (ORs) of the disease response and control rates and grade 3-4 toxicities, and the mean difference (MD) of both progression-free and overall survivals were calculated and used for statistical analysis.

RESULTS: Seven randomized trials with a total of 858 patients were selected and included in the final analysis. The studies were divided into subgroups based on the chemotherapy regimens, including Gem-based and non-Gem-based chemotherapies. The overall analyses revealed that the patients treated with Gem-based combination chemotherapy had significantly higher disease response rates [OR = 1.69, 95% confidence interval (CI): 1.17-2.43; P = 0.01], a longer progression-free survival (MD = 1.95, 95%CI: 0.90-3.00; P = 0.00) and a longer overall survival (MD = 1.85, 95%CI: 0.26-3.44; P = 0.02). A higher incidence of grade 3-4 hematological toxicities, including leukopenia (OR = 2.98, 95%CI: 1.44-6.20; P = 0.00), anemia (OR = 2.96, 95%CI: 1.79-4.92; P = 0.00) and neutropenia (OR = 2.80, 95%CI: 1.39-5.64; P = 0.00) was found in the Gem-based combination chemotherapy group compared with the Gem monotherapy and non-Gem-based chemotherapy groups.

CONCLUSION: Gem-based combination chemotherapy is a potential first-line treatment for advanced biliary tract cancer as a result of improved survival, though with additional toxicity.

Tubulin β-III: a novel immunohistochemical marker for intrahepatic peripheral cholangiocarcinoma

AIMS

Our recent proteomic study identified tubulin β-III (TUBB3) as a potential tissue marker for intrahepatic cholangiocarcinomas (CCs). This validation study was conducted to see whether or not TUBB3 can serve as a novel immunohistochemical marker for peripheral CCs, using a large cohort (n = 197) covering various liver tumours and premalignant conditions.

METHODS AND RESULTS

Immunostaining using a monoclonal antibody demonstrated TUBB3 expression in 14/28 cases of peripheral CCs (50%), while its expression was significantly less common in perihilar CCs (6/40, 15%) (P = 0.002). No significant difference was identified in clinicopathological features between TUBB3-positive and -negative cases. TUBB3 expression was entirely negative in hepatocellular carcinomas, biliary premalignant lesions (i.e., biliary intraepithelial neoplasias, intraductal papillary neoplasms), peribiliary gland hamartomas (bile duct adenomas), and non-neoplastic biliary epithelium. TUBB3 expression was only focally noted in 2/12 cases of mixed hepatocellular and cholangiocarcinomas (<10% of cancer cells). Compared with other biliary (CK7 and CK19) and malignant markers (p53 and MUC1), TUBB3 was less sensitive but more specific for peripheral CCs. TUBB3 was also expressed in 40% of metastatic colorectal or breast cancers.

CONCLUSIONS

This study revealed that TUBB3 is a moderately sensitive and highly specific tissue marker for discriminating peripheral CCs from other primary liver tumours.

Magnetic resonance cholangiography compared with endoscopic retrograde cholangiography in the diagnosis of primary sclerosing cholangitis

BACKGROUND

Magnetic resonance cholangiography (MRC) has gained popularity for diagnosing primary sclerosing cholangitis (PSC). We determined the accuracy of MRC compared with endoscopic retrograde cholangiography (ERC) for diagnosing PSC.

MATERIALS AND METHODS

This retrospective case-control study was conducted on patients referred to an outpatient gastroenterology clinic from 2001 to 2013. Patients with established diagnosis of PSC who had undergone MRC and ERC within a 6-month interval were included. Controls were selected from patients who had undergone imaging for reasons other than PSC evaluation. Disease outcome at the study time and liver biochemistry data at diagnosis and 1-year thereafter were retrieved. Diagnostic accuracy of MRC in comparison with ERC was evaluated.

RESULTS

A total of 46 definite PSC patients (age at diagnosis = 36.8 ± 11.6 years, 33 male) were found. Diagnostic imaging for PSC was ERC alone in 12, MRC alone in 23, and ERC plus MRC in 11 patients. Controls were 89 patients mostly with bile stones. The sensitivity, specificity, and positive and negative likelihood ratios of MRC was 90.9%, 95.5%, 20.23, and 0.10, respectively. Early PSC was found more frequently by MRC compared with ERC (30.4% vs. 8.3%, P = 0.146). No significant difference was found between imaging modalities with regards to patients' outcome (P = 0.786) or liver biochemistry at diagnosis or 1-year thereafter (P >0.05).

CONCLUSION

Starting diagnostic imaging for PSC with MRC seems better and may provide diagnosis of PSC at its earlier phase. Further studies with larger sample of patients and longer follow-ups are warranted.

The role of polycomb repressive complexes in biliary tract cancer

INTRODUCTION

Polycomb group proteins are major epigenetic regulators that modify histone tails. They are organized in two multi-protein complexes called polycomb repressive complex (PRC) 1 and 2. Aberrant PRC activity is known to contribute to the development and aggressiveness of many cancers. Biliary tract cancer (BTC) is a rare malignancy associated with high chemoresistance and poor clinical outcome. Here we review the role of the PRC complexes and the effects of RNAi and drug-mediated inhibition of PRC1 and PRC2 in BTC.

AREAS COVERED

This review gives a short overview of the composition, biochemical functions and oncogenic role of PRC complexes. We then focus on and summarize the results of current studies that address the role of PRC in BTC. Finally, we discuss options and results of therapeutic targeting of PRC in BTC.

EXPERT OPINION

Pharmacological inhibition of the two PRC complexes seems to be a promising strategy for treatment of BTC. To date, only few studies have addressed the therapeutic effect of PRC inhibition in BTC. Therefore, it will be important to test established PRC inhibitors, such as DZNep, as well as newly developed drugs, for example, PTC209, to gain more insight into the role of the PRC complexes in BTC and potentially to develop new therapeutic strategies.

Type II diabetes mellitus is associated with a reduced risk of cholangiocarcinoma in patients with biliary tract diseases

It has not yet been reported whether Type II diabetes mellitus (DM) is associated with an increased cholangiocarcinoma (CC) risk in patients with biliary tract diseases. We identified 123,050 patients concomitantly diagnosed with biliary tract diseases and DM between 1998 and 2010. The control cohort consisted of 122,721 individuals with biliary tract diseases but not DM. Both cohorts were followed-up until the end of 2010 to estimate the risk of CC. We also compared the risk of CC between DM and non-DM cohorts without biliary tract diseases. Overall, the incidence of CC was 21% lower among the DM patients than among the control patients (1.11 vs. 1.41 per 1,000 person-years). DM cohorts exhibited significantly reduced risks for both intrahepatic and extrahepatic CC. A multivariable Cox proportional hazards regression model was used, and the adjusted hazard ratio (HR) of CC was 0.74 (95% confidence interval [CI], 0.66-0.82) for the DM cohort in comparison with the control cohort. The age-specific data indicated that compared with the control patients, the adjusted HRs for the DM patients were significantly lower among patients 50-64 (adjusted HR = 0.67; 95% CI = 0.55-0.82) and 65-74 years old (adjusted HR = 0.70; 95% CI, 0.59-0.84). Furthermore, DM was associated with a lower risk of CC among patients with biliary diseases, regardless of the presence of comorbidities and the status of cholecystectomy. In the patients without biliary tract diseases, DM is associated with significantly increased risk of CC (adjusted HR = 1.58; 95% CI, 1.37-1.82).

Cholangiocarcinoma: molecular pathways and therapeutic opportunities

Cholangiocarcinoma (CCA) is an aggressive biliary tract malignancy with limited treatment options and low survival rates. Currently, there are no curative medical therapies for CCA. Recent advances have enhanced our understanding of the genetic basis of this disease, and elucidated therapeutically relevant targets. Therapeutic efforts in development are directed at several key pathways due to genetic aberrations including receptor tyrosine kinase pathways, mutant IDH enzymes, the PI3K-AKT-mTOR pathway, and chromatin remodeling networks. A highly desmoplastic, hypovascular stroma is characteristic of CCAs and recent work has highlighted the importance of targeting this pathway via stromal myofibroblast depletion. Future efforts should concentrate on combination therapies with action against the cancer cell and the surrounding tumor stroma. As the mutational landscape of CCA is being illuminated, molecular profiling of patient tumors will enable identification of specific mutations and the opportunity to offer directed, personalized treatment options.

Distinct miRNA signatures associate with subtypes of cholangiocarcinoma from infection with the tumourigenic liver fluke Opisthorchis viverrini

BACKGROUND & AIMS

Intrahepatic cholangiocarcinoma (ICC) is a significant public health problem in East Asia, where it is strongly associated with chronic infection by the food-borne parasite Opisthorchis viverrini (OV). We report the first comprehensive miRNA expression profiling by microarray of the most common histologic grades and subtypes of ICC: well differentiated, moderately differentiated, and papillary ICC.

METHODS

MicroRNA expression profiles from FFPE were compared among the following: ICC tumour tissue (n = 16), non-tumour tissue distally macrodissected from the same ICC tumour block (n = 15), and normal tissue (n = 13) from individuals undergoing gastric bypass surgery. A panel of deregulated miRNAs was validated by qPCR.

RESULTS

Each histologic grade and subtype of ICC displayed a distinct miRNA profile, with no cohort of miRNAs emerging as commonly deregulated. Moderately differentiated ICC showed the greatest miRNA deregulation in quantity and magnitude, followed by the papillary subtype, and then well differentiated ICC. Moreover, when ICC tumour tissues were compared to adjacent non-tumour tissue, similar miRNA dysregulation profiles were observed.

CONCLUSIONS

We show that common histologic grades and subtypes of ICC have distinct miRNA profiles. As histological grade and subtypes are associated with ICC aggressiveness, these profiles could be used to enhance the early detection and improve the personalised treatment for ICC. These findings also suggest the involvement of specific miRNAs during ICC tumour progression and differentiation. We plan to use these insights to (a) detect these profiles in circulation and (b) conduct functional analyses to decipher the roles of miRNAs in ICC tumour differentiation.

Curcumin inhibits cell proliferation and induces apoptosis in cholangiocarcinoma

AIM: To investigate the effect of curcumin on proliferation and apoptosis of cholangiocarcinoma cells and whether curcumin shows a therapeutic effect on cholangicarcinoma in vivo.

METHODS: CCK-8 assay was employed to investigate the effect of curcumin on cell proliferation in cholangiocarcinoma cell lines QBC939, RBE and TFK-1. Flow cytometry was employed to assess the effect of curcumin on cell apoptosis in cholangiocarcinoma cell lines. A nude mouse model of orthotopic transplantation of cholangiocarcinoma was developed to investigate the effect of curcumin on weight gain and survival state of mice.

RESULTS: Curcumin inhibited the proliferation of QBC939, RBE and TFK-1 cells (P < 0.05) in a dose- and time-dependent manner. Curcumin significantly induced apoptosis of cholangiocinoma cells. When curcumin concentrations were 0, 0.1, 1, 5 and 10 μmol/L, the corresponding apoptosis rates were 8.41% ± 1.22%, 21.49% ± 2.58%, 48.53% ± 2.41%, 69.75% ± 1.46% and 87.59% ± 3.25%, respectively (P < 0.05). In vivo experimental results show that curcumin significantly prolonged the survival time of tumor-bearing mice (P < 0.05) and significantly improved their survival state (P < 0.05).

CONCLUSION: Curcumin inhibits cell proliferation and induces apoptosis in cholangiocarcinoma cell lines in vitro, and prolongs the survival time of cholangiocarcinoma bearing mice and improve their survival status in vivo.

Endoscopic ultrasound in the diagnosis of cholangiocarcinoma as the etiology of biliary strictures: a systematic review and meta-analysis

BACKGROUND AND AIM

Extrahepatic cholangiocarcinoma (CCA) typically presents as biliary strictures. Endoscopic ultrasound (EUS)-fine needle aspiration (FNA) may contribute to the diagnosis of CCA as the etiology of extrahepatic biliary strictures. Our aim was to study the uselfulness of EUS-FNA in diagnosing CCA as the etiology of biliary strictures.

PATIENTS AND METHODS

In this meta-analysis, PUBMED and EMBASE databases were examined to find studies published to April 2014 where diagnostic correlation of CCA was available. Studies reporting only "positive for malignancy" were included in our analysis. The main outcome measurements were sensitivity, specificity and likelihood ratio.

RESULTS

Six studies were included, covering 196 patients. The overall pooled sensitivity and negative likelihood ratio (LR-) of EUS-FNA for diagnosis of CCA were 66% [95% confidence interval (CI) 57-74%] and 0.34 (95% CI 0.26-0.43), respectively. In five studies (146 patients), where a mass lesion was detected during EUS, the pooled sensitivity and LR- of EUS-FNA for diagnosis of CCA were 80% [95% CI 72-87%] and 0.20 (95% CI 0.13-0.28), respectively. In the 49 patients with a negative brush cytology, the pooled sensitivity and LR- of EUS-FNA for diagnosis of CCA were 59% [95% CI 44-73%] and 0.41 (95% CI 0.27-0.56), respectively.

CONCLUSIONS

Our study suggests that EUS-FNA is useful in the evaluation of CCA as the etiology of biliary strictures. EUS-FNA may improve the diagnosis of CCA in patients with negative cytology and no mass on cross-sectional imaging.

Prognostic impact of tumoral and/or peri-tumoral stromal SPARC expressions after surgery in patients with biliary tract cancer

BACKGROUND AND OBJECTIVE

SPARC (secreted protein acidic and rich in cysteine) is a matricellular glycoprotein that modulates interactions between tumoral cells and the peri-tumoralstroma. SPARC induces proliferation and invasion in vitro, and is a poor prognostic factor in several gastrointestinal cancers. Herein, we evaluated the prognostic value of tumoral and stromal SPARC expression in patients with biliary tract cancer (BTC) after surgery.

METHODS

We examined immunohistochemical patterns of SPARC expression in 110 resected BTC specimens and evaluated the prognostic value using prospectively collected data.

RESULTS

SPARC was expressed in tumoral cells in 46 samples (42%) and inperi-tumoralstromain 65 samples (59%). Tumoral SPARC expression was not related to major patient characteristics. Stromal SPARC expression was related to lymph node metastasis, stage, margin status, and tumor location. Overall survival at 5 years after surgery was 34.2%. Stromal SPARC (P < 0.001) and tumoral SPARC (P = 0.048) were associated with poor prognosis. Multivariate analysis revealed invasion into lymphatic system, residual tumor, and stromal SPARC as independent prognostic factors. The hazard ratio for patients with positive stromal SPARC was 3.20 (P < 0.001).

CONCLUSION

SPARC expression inperi-tumoralstroma predicts a poor prognosis for patients with BTC after surgery.

Platelet-derived growth factor primes cancer-associated fibroblasts for apoptosis

Desmoplastic malignancies such as cholangiocarcinoma (CCA) are characterized by a dense stroma containing an abundance of myofibroblasts termed cancer-associated fibroblasts (CAF). The CAF phenotype represents an "activated state" in which cells are primed for cell death triggered by BH3 mimetics. Accordingly, this primed state may be therapeutically exploited. To elucidate the mechanisms underlying this poorly understood apoptotic priming, we examined the role of platelet-derived growth factor (PDGF) in CAF priming for cell death given its prominent role in CAF activation. PDGF isomers PDGF-B and PDGF-D are abundantly expressed in CCA cells derived from human specimens. Either isomer sensitizes myofibroblasts to cell death triggered by BH3 mimetics. Similar apoptotic sensitization was observed with co-culture of myofibroblasts and CCA cells. Profiling of Bcl-2 proteins expressed by PDGF-primed myofibroblasts demonstrated an increase in cellular levels of Puma. PDGF-mediated increases in cellular Puma levels induced proapoptotic changes in Bak, which resulted in its binding to Bcl-2. Short hairpin RNA-mediated down-regulation of Puma conferred resistance to PDGF-mediated apoptotic priming. Conversely, the BH3 mimetic navitoclax disrupted Bcl-2/Bak heterodimers, allowing Bak to execute the cell death program. Treatment with a Bcl-2-specific BH3 mimetic, ABT-199, reduced tumor formation and tumor burden in a murine model of cholangiocarcinoma. Collectively, these findings indicate that apoptotic priming of CAF by PDGF occurs via Puma-mediated Bak activation, which can be converted to active full-blown apoptosis by navitoclax or ABT-199 for therapeutic benefit.

The expression of S100A4 protein in human intrahepatic cholangiocarcinoma: clinicopathologic significance and prognostic value

Intrahepatic cholangiocarcinoma(ICC) is a highly malignant adenocarcinoma arising from bile duct epithelial cells of the intrahepatic biliary system with early hematogenous and lymphatic extrahepatic spread. The current treatment methods for ICC are far from ideal. Identifying novel effective prognostic biomarkers which might be related to the development and progression of ICC may help provide new therapeutic strategies. Both calcium-binding protein S100A4 and Matrix metalloproteinase-9(MMP-9) are correlated with development and progression of many carcinomas. In the present study, we investigated expression of S100A4 as well as MMP-9 in ICC tissues from 65 patients using immunohistochemistry. The correlation of S100A4 and MMP-9 expression with clinicopathological features and prognosis of patients were analyzed. S100A4 and MMP-9 were positively expressed in 32(49.2 %) and 35(53.8%) patients, respectively. The positive correlation between S100A4 and MMP-9 expression was statistically significant (P = 0.018). S100A4 positive expression was significantly correlated with vascular invasion (P = 0.008), lymph node metastasis (P = 0.029) and the TNM stage (P = 0.008). MMP-9 expression was not found to be correlated with any clinicopathological parameter. Patients with S100A4 positive expression had a significantly poorer overall survival rate than those with S100A4 negative expression (P = 0.000). MMP-9 positive expression was also correlated with poor survival (P = 0.044). However, only S100A4 expression (P = 0.004) and the surgical margin (P = 0.024) were significantly independent prognostic predictors by multivariate analysis. In conclusion, expression of S100A4 is correlated with MMP-9 expression and it could be a useful marker for predicting the progression, metastasis and prognosis of ICC.

Is there a role for second-line platinum re-challenge in advanced biliary tract cancers?

The clinical benefit of second-line chemotherapy in advanced biliary tract cancers is currently unknown. We investigated the role of platinum re-challenge in a selected cohort of patients who progressed after first-line gemcitabine/cisplatin (GemCis) chemotherapy. We retrospectively analysed seventy-four patients treated between January 2008 and September 2012 at Nottingham University Hospitals. Demographics, treatment data, radiological response and survival data were captured. Univariate and multivariate analysis of survival outcomes were evaluated. Platinum sensitive disease was defined as tumours that progress after 12 weeks of completion of first-line GemCis chemotherapy. Seventy-four patients (median age = 67 years) had received first-line chemotherapy (gemcitabine alone = 21/74, Gem/Cis combination = 53/74). Best response to GemCis chemotherapy was as follows; partial response (PR) (17 %), stabilisation of disease (SD) (39.6 %), disease control rate (DCR) (56.6 %) and disease progression (43.4 %). 18/74 patients received second-line chemotherapy [GemCis (12/18), 5-FU/cisplatin (4/18), gemcitabine (2/8)]. Best response to GemCis second-line chemotherapy was as follows: PR (33.3 %), SD (33.3 %) and DCR (66.6 %). The median overall survival in patients who received second-line chemotherapy was 29 months compared to 10.6 months in patients who received first-line therapy only (p = 0.00001). The data suggest that patients who progress after 12 weeks of completion of first-line therapy may remain platinum sensitive and benefit from second-line platinum re-challenge. Prospective multicentre studies are warranted to explore this possibility further.

Current status of the organ replacement approach for malignancies and an overture for organ bioengineering and regenerative medicine

Significant achievements in the organ replacement approach for malignancies over the last 2 decades opened new horizons, and the age of "Transplant Oncology" has dawned. The indications of liver transplantation for malignancies have been carefully expanded by a strict patient selection to assure comparable outcomes with non-malignant diseases. Currently, the Milan criteria, gold standard for hepatocellular carcinoma, are being challenged by high-volume centers worldwide. Neoadjuvant chemoradiation therapy and liver transplantation for unresectable hilar cholangiocarcinoma has been successful in specialized institutions. For other primary and metastatic liver tumors, clinical evidence to establish standardized criteria is lacking. Intestinal and multivisceral transplantation is an option for low-grade neoplasms deemed unresectable by conventional surgery. However, the procedure itself is in the adolescent stage. Solid organ transplantation for malignancies inevitably suffers from "triple distress," i.e., oncological, immunological, and technical. Organ bioengineering and regenerative medicine should serve as the "triple threat" therapy and revolutionize "Transplant Oncology."

Chronic inflammation and cytokines in the tumor microenvironment

Acute inflammation is a response to an alteration induced by a pathogen or a physical or chemical insult, which functions to eliminate the source of the damage and restore homeostasis to the affected tissue. However, chronic inflammation triggers cellular events that can promote malignant transformation of cells and carcinogenesis. Several inflammatory mediators, such as TNF-α, IL-6, TGF-β, and IL-10, have been shown to participate in both the initiation and progression of cancer. In this review, we explore the role of these cytokines in important events of carcinogenesis, such as their capacity to generate reactive oxygen and nitrogen species, their potential mutagenic effect, and their involvement in mechanisms for epithelial mesenchymal transition, angiogenesis, and metastasis. Finally, we will provide an in-depth analysis of the participation of these cytokines in two types of cancer attributable to chronic inflammatory disease: colitis-associated colorectal cancer and cholangiocarcinoma.

Angiopoietin-2 and biliary diseases: elevated serum, but not bile levels are associated with cholangiocarcinoma

Background

The diagnosis of cholangiocarcinoma (CC) is challenging especially in patients with primary sclerosing cholangitis (PSC) and often delayed due to the lack of reliable markers. Angiopoietin-2 (Angpt-2) has been employed as a biomarker of angiogenesis and might be involved in tumor neoangiogenesis.

Aim

To evaluate the diagnostic potential of Angpt-2 as a biomarker to detect patients with CC.

Methods

Bile and serum Angpt-2 levels were measured in patients with CC (n = 45), PSC (n = 74), CC complicating PSC (CC/PSC) (n = 11) and patients with bile duct stones (n = 37) in a cross sectional study. Diagnostic accuracy of Angpt-2 was compared to carbohydrate antigen 19-9 (CA19-9). Fluorescent immunohistochemistry from human CC liver tissue samples was performed to localize the origin of Angpt-2.

Results

Serum Angpt-2 concentration was significantly elevated in patients with CC compared to control patients (p<0.05). Diagnostic accuracy of Angpt-2 as determined by receiver operating characteristic (ROC) analysis resulted in a higher area under the curve (AUC) value compared to CA19-9 (AUC: 0.85 versus 0.77; 95% confidence interval (CI): 0.74–0.93 versus 0.65–0.87, respectively). Angpt-2 was also detectable in bile, but was not associated with the presence of CC. Immunohistochemistry revealed a strong induction of Angpt-2 expression in the tumor vasculature.

Conclusions

Circulating Angpt-2 in serum might be a promising protein candidate locally derived from the tumor vasculature in patients with CC. Measurement of Angpt-2 in serum may be useful for diagnosis and further clinical management of patients with CC.

Activating mutations in PTPN3 promote cholangiocarcinoma cell proliferation and migration and are associated with tumor recurrence in patients

BACKGROUND & AIMS

The pathogenesis of intrahepatic cholangiocarcinoma (ICC), the second most common hepatic cancer, is poorly understood, and the incidence of ICC is increasing worldwide. We searched for mutations in human ICC tumor samples and investigated how they affect ICC cell function.

METHODS

We performed whole exome sequencing of 7 pairs of ICC tumors and their surrounding nontumor tissues to detect somatic alterations. We then screened 124 pairs of ICC and nontumor samples for these mutations, including 7 exomes. We compared mutations in PTPN3 with tumor recurrence in 124 patients and PTPN3 expression levels with recurrence in 322 patients (the combination of both in 86 patients). The functional effects of PTPN3 variations were determined by RNA interference and transgenic expression in cholangiocarcinoma cell lines (RBE, HCCC-9810, and Huh28).

RESULTS

Based on exome sequencing, pathways that regulate protein phosphorylation were among the most frequently altered in ICC samples and genes encoding protein tyrosine phosphatases (PTPs) were among the most frequently mutated. We identified mutations in 9 genes encoding PTPs in 4 of 7 ICC exomes. In the prevalence screen of 124 paired samples, 51.6% of ICCs contained somatic mutations in at least 1 of 9 PTP genes; 41.1% had mutations in PTPN3. Transgenic expression of PTPN3 in cell lines increased cell proliferation, colony formation, and migration. PTPN3(L232R) and PTPN3(L384H), which were frequently detected in ICC samples, were found to be gain-of-function mutations; their expression in cell lines further increased cell proliferation, colony formation, and migration. ICC-associated variants of PTPN3 altered phosphatase activity. Patients whose tumors contained activating mutations or higher levels of PTPN3 protein than nontumor tissues had higher rates of disease recurrence than patients whose tumors did not have these characteristics.

CONCLUSIONS

Using whole exome sequencing of ICC samples from patients, we found that more than 40% contain somatic mutations in PTPN3. Activating mutations in and high expression levels of PTPN3 were associated with tumor recurrence.

Mutations of isocitrate dehydrogenase 1 and 2 in intrahepatic cholangiocarcinoma

PURPOSE OF REVIEW

Exome sequencing studies have recently expanded the genetic characterization of intrahepatic cholangiocarcinomas. Among a number of novel genes, isocitrate dehydrogenase (IDH) is recurrently mutated in intrahepatic cholangiocarcinomas. We review the effects of these mutations on several biochemical pathways, as well as potential changes to downstream signaling pathways.

RECENT FINDINGS

Hotspot mutations in IDH isoforms 1 or 2 occur in approximately 15% of intrahepatic cholangiocarcinomas. These mutations result in elevated levels of an oncometabolite, 2-hydroxyglutarate, which is associated with higher DNA CpG methylation and altered histone methylation that accompany a block in cellular differentiation. Exploratory studies have suggested additional phenotypes associated with IDH1/2 mutations.

SUMMARY

Tumors with IDH1 or IDH2 mutations may represent a distinct subtype of cholangiocarcinomas. Further studies are required to elucidate the exact role that mutant IDH1/2 and 2-hydroxyglutarate play in tumorigenesis, and what are the best strategies to target these tumor types.

Triptolide induces apoptotic cell death of human cholangiocarcinoma cells through inhibition of myeloid cell leukemia-1

BACKGROUND

Cholangiocarcinoma (CCA), a devastating neoplasm, is highly resistant to current chemotherapies. CCA cells frequently overexpress the antiapoptotic protein myeloid cell leukemia-1(Mcl-1), which is responsible for its extraordinary ability to evade cell death. Triptolide, a bioactive ingredient extracted from Chinese medicinal plant, has been shown to inhibit cell proliferation and induce apoptosis in several cancers.

METHODS

CCK-8 assay was performed to detect cell survival rate in vitro. DAPI staining and Flow cytometry were used to analyze apoptosis. Western blot was performed to determine the expression levels of caspase-3, caspase-7, caspase-9, PARP, and Mcl-1. Quantitative real-time PCR and immunofluorescence were used to detect the expression levels of Mcl-1. The nude mice xenograft model was used to evaluate the antitumor effect of triptolide in vivo.

RESULTS

Triptolide reduced cell viability in cholangiocarcinoma cell lines in a dose- and time-dependent manner, with IC50 values of 12.6 ± 0.6 nM, 20.5 ± 4.2 nM, and 18.5 ± 0.7 nM at 48 h for HuCCT1, QBC939, and FRH0201 respectively. Triptolide induced apoptosis in CCA cell lines in part through mitochondrial pathway. Using quantitative real-time PCR, western blot and immunofluorescence, we have shown that triptolide downregulates Mcl-1 mRNA and protein levels. Furthermore, triptolide inhibited the CCA growth in vivo.

CONCLUSIONS

Triptolide has profound antitumor effect on CCA, probably by inducing apoptosis through inhibition of Mcl-1. Triptolide would be a promising therapeutic agent for CCA.

Identification of potential serum peptide biomarkers of biliary tract cancer using MALDI MS profiling

BACKGROUND

The aim of this discovery study was the identification of peptide serum biomarkers for detecting biliary tract cancer (BTC) using samples from healthy volunteers and benign cases of biliary disease as control groups. This work was based on the hypothesis that cancer-specific exopeptidases exist and that their activities in serum can generate cancer-predictive peptide fragments from circulating proteins during coagulation.

METHODS

This case control study used a semi-automated platform incorporating polypeptide extraction linked to matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) to profile 92 patient serum samples. Predictive models were generated to test a validation serum set from BTC cases and healthy volunteers.

RESULTS

Several peptide peaks were found that could significantly differentiate BTC patients from healthy controls and benign biliary disease. A predictive model resulted in a sensitivity of 100% and a specificity of 93.8% in detecting BTC in the validation set, whilst another model gave a sensitivity of 79.5% and a specificity of 83.9% in discriminating BTC from benign biliary disease samples in the training set. Discriminatory peaks were identified by tandem MS as fragments of abundant clotting proteins.

CONCLUSIONS

Serum MALDI MS peptide signatures can accurately discriminate patients with BTC from healthy volunteers.