New insights into cholangiocarcinoma: multiple stems and related cell lineages of origin

VSTM2L is a promising therapeutic target and a prognostic soluble-biomarker in cholangiocarcinoma

The aim of the present study is to provide a rational background for silencing the V-set and transmembrane domain containing 2 like (VSTM2L) in consort with recognising soluble VSTM2L against cholangiocarcinoma. A therapeutic target against cholangiocarcinoma was selected using iterative patient partitioning (IPP) calculation, and it was verified by in vitro and in silico analyses. VSTM2L was selected as a potential therapeutic target against cholangiocarcinoma. Silencing the VSTM2L expression significantly attenuated the viability and survival of cholangiocarcinoma cells through blockade of the intracellular signalling pathway. In silico analysis showed that VSTM2L affected the positive regulation of cell growth in cholangiocarcinoma. Liptak's z value revealed that the expression of VSTM2L worsened the prognosis of cholangiocarcinoma patients. In addition, soluble VSTM2L was significantly detected in the whole blood of cholangiocarcinoma patients compared with that of healthy donors. Our report reveals that VSTM2L might be the potential therapeutic target and a soluble prognostic biomarker against cholangiocarcinoma. [BMB Reports 2024; 57(7): 324-329].

Inflammatory responses to Opisthorchis viverrini infection in animal models: A comparison between susceptible and nonsusceptible hosts in different anatomical locations

Background

Inflammation caused by Opisthorchis viverrini infection increases the risk of cholangitis, cholecystitis, and leads to bile duct cancer (cholangiocarcinoma or CCA). However, only certain infected individuals are susceptible to CCA, suggesting the involvement of host factors in cancer development. In addition, there are reports indicating differences in the locations of CCA.

Aim

This study aims to investigate cellular inflammatory responses in the common bile duct (CB), intrahepatic bile duct (IHB), and gallbladder (GB) in susceptible and non-susceptible hosts following O. viverrini infection.

Methods

Thirty Syrian golden hamsters (a susceptible host) and 30 BALB/c mice (a non-susceptible host) infected with O. viverrini were studied at six time points (five animals per group). Histopathological evaluations were conducted on samples from the IHB, CB, and GB. Inflammatory cell infiltration was quantitatively assessed and compared between groups and time points. Statistical analysis was performed using one-way ANOVA, with a significance level of p < 0.05.

Results

Inflammation was significantly more pronounced in the IHB compared to the other two biliary locations. In comparison between susceptible and non-susceptible hosts, the intensity of inflammation was higher in the OV+H group than in the OV+M group (p < 0.05).

Conclusion

This study highlights the association between host response to inflammation, tissue location, and host susceptibility, with the IHB showing particular susceptibility to inflammation and pathological changes. These findings contribute to our understanding of the increased risk of CCA in susceptible hosts.

LINC00844 suppresses tumor progression and predicts survival outcomes through inhibiting miR-19a-5p in cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is a heterogeneous malignancy. The aim of the study was to investigate the regulatory role of long noncoding RNA LINC00844 in CCA progression, explore the underlying molecular mechanisms, and to analyze the potential prognostic value of LINC00844 in CCA patients.

METHODS

Expression of LINC00844 in CCA cell lines and tissues was examined by reverse transcription-quantitative PCR. Cell counting kit-8 assay was used to assess CCA cell proliferation, and the Transwell assay was used to evaluate tumor cell migration and invasion. miRNAs sponged by LINC00844 were predicted and confirmed using a luciferase reporter assay. Kaplan-Meier survival analysis was performed to evaluate the survival prognosis of CCA patients.

RESULTS

The expression levels of LINC00844 were decreased in CCA tissues and cells. Overexpression of LINC00844 inhibited cell proliferation, migration and invasion in CCA cells. miR-19a-5p is directly targeted by LINC00844, mediating the inhibitory effects of LINC00844 on the proliferation, migration and invasion of CCA cells. LINC00844 and miR-19a-5p expression were associated with differentiation and tumor node metastasis stage in CCA patients. CCA patients with low LINC00844 expression or overexpression of miR-19a-5p had worse overall survival.

CONCLUSION

The expression levels of LINC00844 were decreased in both CCA tissues and cells, and high LINC00844 inhibited CCA cell proliferation, migration and invasion through sponging miR-19a-5p. Low LINC00844 and high miR-19a-5p expression were associated with worse overall survival in CCA patients. All the data suggested that the LINC00844/miR-19a-5p axis may provide novel therapeutic targets and prognostic biomarkers for CCA patients.

Treatment with palbociclib and tislelizumab for CDKN2A-mutated and PD-L1-positive advanced intrahepatic cholangiocarcinoma: a case report and literature review

Background

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver malignancy with a steadily increasing incidence worldwide. ICC has insidious onset, rapid progression, and poor prognosis. More multidisciplinary clinical studies are needed to continuously explore safer and more efficient diagnosis and treatment modes for ICC.

Methods and results

A 66-year-old female patient with ICC rapidly developed systemic multiple metastases after surgery, and the first-line two-drug combination chemotherapy was not effective. Due to cyclin-dependent kinase inhibitor 2A mutation and programmed cell death-ligand 1-positive, a partial response and progression-free survival of 9.5 months were achieved after a second-line treatment with cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) combined with immunotherapy. The patient developed thromboembolism 7 months after treatment and died due to disseminated intravascular coagulation.

Conclusion

The combination of targeted and immune therapy has revealed a potentially effective regimen for the effective treatment of patients with ICC, which needs to be observed in larger clinical studies. The thromboembolism rates in real-world patients treated with CDK4/6 inhibitors are higher than those reported in clinical trials, and the application of prophylactic anticoagulation in this patient population may be questionable.

Intrahepatic Cholangiocarcinoma and Hepatocellular Carcinoma: Real-life Data on Liver Disease, Treatment and Prognosis

Background and Aims

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA) have common features and differences. This real-life study investigated their characteristics, treatment modalities, and prognoses.

Methods

This retrospective comparative study was performed in 1,075 patients seen at one tertiary center between January 2008 and December 2020. Overall survival (OS) was estimated by the Kaplan-Meier method. Subclassification of iCCAs after histological and radiological review, and molecular profiling was performed.

Results

HCCs patients were more likely to have early-stage disease than iCCA patients. iCCA patients were more likely to be female, especially those patients without cirrhosis (43% vs. 17%). Cirrhosis was prominent among HCC patients (89% vs. 34%), but no difference in underlying liver disease among cirrhotic patients was found. OS of HCC patients was 18.4 (95% CI: 6.4, 48.3) months, that of iCCA patients was 7.0 (95% CI: 3.4, 20.1) months. OS of Barcelona Clinic Liver Cancer C HCC patients was 7.8 (95% CI: 4.3, 14.2) months, that of advanced/metastatic iCCA patients was 8.5 (95% CI: 5.7, 12.3) months. In patients treated with sorafenib, OS was longer in HCC patients who received subsequent tyrosine kinase inhibitor therapies. No significant OS difference was found between iCCA patients with and without cirrhosis or according to histological subtype. A targetable molecular alteration was detected in 50% of the iCCA patients.

Conclusions

In this French series, cirrhosis was common in iCCA, which showed etiological factors comparable to those of HCC, implying a distinct oncogenic pathway. Both entities had a dismal prognosis at advanced stages. However, systemic therapies sequencing in HCC and molecular profiling in iCCA offer new insights.

ROR1-AS1 might promote in vivo and in vitro proliferation and invasion of cholangiocarcinoma cells

Long non-coding RNAs (lncRNAs) play important roles in many pathophysiological processes, including cancer progression. Namely, lncRNA Receptor-tyrosine-kinase-like orphan receptor-1 antisense 1 (ROR1-AS1) is crucial for cancer occurrence and progression in organs such as the liver or bladder. However, its expression and role in cholangiocarcinoma (CCA) have not been thoroughly explored.Firstly, we assessed cell viability, proliferation, invasion, and migration using three cell lines (HuCCT-1, QBC399, and RBE) to explore the biological characteristics of ROR1-AS1 in CCA. Secondly, to determine the in vivo effect of ROR1-AS1 on tumor growth, ROR1-AS1 knockdown (KD) HuCCT-1 cells were subcutaneously injected into nude mice to evaluate tumor growth. Finally, we conducted a bioinformatic analysis to confirm the role of ROR1-AS1 in the prognosis and immunity of CCA.In this study, we found that lncRNA ROR1-AS1 was increased in CCA samples and patients with higher ROR1-AS1 expression had a shorter overall survival period. siRNA-mediated KD of ROR1-AS1 significantly reduced cell proliferation and inhibited the migration of CCA cells. In addition, ROR1-AS1 KD HuCCT-1 cells injected into nude mice grew slower than normal CCA cells.In summary, our results show that ROR1-AS1 can promote CCA progression and might serve as a new target for diagnosis and treatment of CCA.

Anti-PD-1-based immunotherapy plus lenvatinib to treat advanced gallbladder cancer in the elderly: a case series and review of current literature

BACKGROUND

Gallbladder cancer (GBC) is a rare malignant tumour of the bile duct. Due to the lack of typical clinical manifestations in the early stage, it is basically at an advanced stage when discovered. Radical resection remains the only curative therapy for patients with GBC. The resection rate is relatively low due to tumour invasion and metastasis, and the overall prognosis is poor. For most patients with unresectable lesions, chemotherapy has been the only recommended treatment for decades. Immunotherapy combined with TKIs (tyrosine kinase inhibitors) was proven to be effective in patients with hepatocellular carcinoma and cholangiocarcinoma. Some physicians have attempted to apply immunotherapy and TKIs combined with traditional chemotherapy in patients with advanced GBC. However, the outcomes were not clear because limited cases were reported.

CASE PRESENTATION

We present a case series of four elderly patients with advanced GBC who received tislelizumab and lenvatinib combined with chemotherapy. All four patients responded to this treatment approach. Tumour responses were better in Patient 1 (TMB-H, MSS), Patient 2 (low TMB, MSS), and Patient 3 (low TMB, MSI-H) than in Patient 4 (low TMB, MSS), in whom metastasis occurred during the later stage of treatment.

CONCLUSION

The combination of tislelizumab and lenvatinib may be a promising treatment for patients with advanced GBC. The efficacy and safety need further confirmation.

Implication of Ferroptosis in Cholangiocarcinoma: A Potential Future Target?

Cholangiocarcinoma (CCA), the second most common liver neoplasm, has a poor overall 5-year survival rate of less than 10%. A deeper understanding of the molecular pathogenesis contributing to CCA progression is essential for developing better therapeutic approaches to manage this disease. Ferroptosis, an oxidative iron-dependent form of regulated cell death, has been reported to be involved in tumorigenesis and progression. In particular, ferroptosis and inflammation, which are common issues in cholangiocarcinogenesis and CCA development, might be in concert with disease progression. Notably, the key feature of cancer cells is "iron addiction", which is crucial for the high metabolic demand in carcinogenesis and cancer progression. Additionally, iron metabolism is of great importance in ferroptosis. Moreover, that cancer cells are vulnerable to ferroptosis might be a possible mechanism of CCA development. Although the underlying mechanism of how ferroptosis is implicated in CCA development requires further investigation, developing a new strategy combined with a pro-ferroptotic treatment would be an exciting CCA treatment approach in the future.

Study of the association between a MICA gene polymorphism and cholangiocarcinoma in Egyptian patients

Introduction

An inflammatory environment is the common pathway for the development of cholangiocarcinoma (CCA). The natural killer group 2D receptor (NKG2D), an activating receptor for NK cells, is a potent immune axis in the antitumor and antimicrobial immune response through its binding to NKG2D ligands (NKG2DLs). NKG2DLs are normally absent or poorly expressed in most cells; conversely, they are upregulated in stressed cells. We studied the rs2596542 polymorphism located upstream of the MICA gene, which encodes an NKG2DL, in patients with CCA as a marker for early disease detection and a possible therapeutic target.

Material and methods

A case-control study was conducted on 40 patients with CCA and 45 healthy individuals (as controls). After routine examination, the rs2596542 polymorphism of the MICA gene was investigated using real-time PCR.

Results

We found that a TT homozygous genotype was significantly predominant in patients with CCA (p = 0.039), with the T allele being dominantly distributed in CCA (p = 0.007). High levels of CA19-9 were significantly associated with the TT genotype in the patients. However, we did not detect significant differences in rs2596542C/T genotype and allele distribution between patients with CCA with cirrhosis and those without cirrhosis (p > 0.05).

Conclusions

The MICA rs2596542 polymorphism may affect the susceptibility to CCA, but not its progression. The TT genotype could be used as a potential diagnostic marker for CCA and triggering the MICA pathway could be a promising therapeutic target.

Understanding the Immunoenvironment of Primary Liver Cancer: A Histopathology Perspective

One of the most common cancers worldwide, primary liver cancer remains a major cause of cancer-related mortality. Hepatocellular carcinoma and cholangiocarcinoma represent the majority of primary liver cancer cases. Despite advances in the development of novel anti-cancer therapies that exploit targets within the immune system, survival rates from liver cancer remain poor. Furthermore, responses to immunotherapies, such as immune checkpoint inhibitors, have revealed limited and variable responses amongst patients with hepatocellular carcinoma, although combination immunotherapies have shown recent breakthroughs in clinical trials. This has shifted the focus towards improving our understanding of the underlying immune and molecular characteristics of liver tumours that may influence their response to immune-modulating treatments. In this review, we outline the complex interactions that occur in the tumour microenvironment of hepatocellular carcinoma and cholangiocarcinoma, respectively, from a histopathological perspective. We explore the potential role of a classification system based on immune-specific characteristics within each cancer type, the importance of understanding inter- and intra-tumoural heterogeneity and consider the future role of histopathology and novel technologies within this field.

NOTCH-YAP1/TEAD-DNMT1 Axis Drives Hepatocyte Reprogramming Into Intrahepatic Cholangiocarcinoma

BACKGROUND & AIMS

Intrahepatic cholangiocarcinoma (ICC) is a devastating liver cancer with extremely high intra- and inter-tumoral molecular heterogeneity, partly due to its diverse cellular origins. We investigated clinical relevance and the molecular mechanisms underlying hepatocyte (HC)-driven ICC development.

METHODS

Expression of ICC driver genes in human diseased livers at risk for ICC development were examined. The sleeping beauty and hydrodynamic tail vein injection based Akt-NICD/YAP1 ICC model was used to investigate pathogenetic roles of SRY-box transcription factor 9 (SOX9) and yes-associated protein 1 (YAP1) in HC-driven ICC. We identified DNA methyltransferase 1 (DNMT1) as a YAP1 target, which was validated by loss- and gain-of-function studies, and its mechanism addressed by chromatin immunoprecipitation sequencing.

RESULTS

Co-expression of AKT and Notch intracellular domain (NICD)/YAP1 in HC yielded ICC that represents 13% to 29% of clinical ICC. NICD independently regulates SOX9 and YAP1 and deletion of either, significantly delays ICC development. Yap1 or TEAD inhibition, but not Sox9 deletion, impairs HC-to-biliary epithelial cell (BEC) reprogramming. DNMT1 was discovered as a novel downstream effector of YAP1-TEAD complex that directs HC-to-BEC/ICC fate switch through the repression of HC-specific genes regulated by master regulators for HC differentiation, including hepatocyte nuclear factor 4 alpha, hepatocyte nuclear factor 1 alpha, and CCAAT/enhancer-binding protein alpha/beta. DNMT1 loss prevented NOTCH/YAP1-dependent HC-driven cholangiocarcinogenesis, and DNMT1 re-expression restored ICC development following TEAD repression. Co-expression of DNMT1 with AKT was sufficient to induce tumor development including ICC. DNMT1 was detected in a subset of HCs and dysplastic BECs in cholestatic human livers prone to ICC development.

CONCLUSION

We identified a novel NOTCH-YAP1/TEAD-DNMT1 axis essential for HC-to-BEC/ICC conversion, which may be relevant in cholestasis-to-ICC pathogenesis in the clinic.

Comparison of growth features and cancer stem cell prevalence in intrahepatic and extrahepatic cholangiocarcinoma cell lines

Aim of the study

Intra- and extrahepatic cholangiocarcinoma (I-CCA and E-CCA respectively) exhibit different growth features that contribute to different clinical outcomes. Cancer stem cells (CSCs) influence tumor growth and thereby may be responsible for these differences. The aim of this study was to document and compare the growth features of human I-CCA and E-CCA cell lines and determine whether any differences observed could be explained by differences in the prevalence and/or stem cell surface marker (SCSM) expression profiles of CSCs within the tumor cell lines.

Material and methods

Six CCA cells lines, three I-CCA and three E-CCA, were studied. Tumor cell growth features including cell proliferation, colony/spheroid formation, migration and invasion were documented. CSC prevalence and SCSM expression profiles were examined by flow cytometry.

Results

I-CCA cells had significantly increased proliferative activity, shorter doubling times and were more invasive than E-CCA cells, while colony/spheroid formation and migration were similar in the two cell populations. There were no significant differences in CSC prevalence rates or SCSM expression profiles.

Conclusions

These findings suggest that I-CCA cells proliferate at a more rapid rate and are more invasive than E-CCA cells but the differences cannot be explained by differences in the prevalence or SCSM expression profiles of CSCs within the tumor cell population.

Soluble TGFBI aggravates the malignancy of cholangiocarcinoma through activation of the ITGB1 dependent PPARγ signalling pathway

BACKGROUND

Cholangiocarcinoma is a devastating cancer with a poor prognosis. Previous reports have presented conflicting results on the role of transforming growth factor-β-induced protein (TGFBI) in malignant cancers. Currently, our understanding of the role of TGFBI in cholangiocarcinoma is ambiguous. The aim of the present study was to investigate the role of TGFBI in human cholangiocarcinoma.

METHODS

Iterative patient partitioning (IPP) scoring and consecutive elimination methods were used to select prognostic biomarkers. mRNA and protein expression levels were determined using Gene Expression Omnibus (GEO), Western blot and ELISA analyses. Biological activities of selected biomarkers were examined using both in vitro and in vivo assays. Prognostic values were assessed using Kaplan-Meier and Liptak's z score analyses.

RESULTS

TGFBI was selected as a candidate cholangiocarcinoma biomarker. GEO database analysis revealed significantly higher TGFBI mRNA expression levels in cholangiocarcinoma tissues compared to matched normal tissues. TGFBI protein was specifically detected in a soluble form in vitro and in vivo. TGFBI silencing evoked significant anti-cancer effects in vitro. Soluble TGFBI treatment aggravated the malignancy of cholangiocarcinoma cells both in vitro and in vivo through activation of the integrin beta-1 (ITGB1) dependent PPARγ signalling pathway. High TGFBI expression was associated with a poor prognosis in patients with cholangiocarcinoma.

CONCLUSIONS

Our data suggest that TGFBI may serve as a promising prognostic biomarker and therapeutic target for cholangiocarcinoma.

Immune cell atlas of cholangiocarcinomas reveals distinct tumor microenvironments and associated prognoses

BACKGROUND

Immunotherapy has demonstrated a limited clinical efficacy in approximately 5% of cholangiocarcinoma. The main challenges for an effective immunotherapy response in cholangiocarcinoma arise from the tumor microenvironment, which is poorly understood.

METHODS

For a comprehensive analysis of the tumor microenvironment in cholangiocarcinoma, we performed multiplex immunohistochemistry with two 15-marker immune panels and Nanostring assays for a comprehensive analysis of 104 surgically resected cholangiocarcinomas including intrahepatic, hilar, and distal cholangiocarcinoma. We also validated some key findings with a batch integration analysis of published single cell RNA sequencing data.

RESULTS

This study found that natural killer cells occupy the largest immune cell compartment in cholangiocarcinoma. Granzyme-B+CD8+ effector T cells are significantly associated with better overall survival in both intrahepatic and distal cholangiocarcinoma. Above 85% of intrahepatic cholangiocarcinomas with higher density of PD-1-EOMES-CD8+ effector T cells are associated with long-term survival. However, only the density of PD-1-EOMES-CD8+ T cells in the tumor areas, but not in the peripheries of the tumors, is prognostic. In all three cholangiocarcinoma subtypes, T regulator cells are significantly associated with a poor prognosis; however, M1 and M2 tumor-associated macrophages or PD-L1+ tumor-associated macrophage demonstrate different prognostic values. Combining PD-L1+ M1 or M2, PD-L1- M1 or M2 tumor-associated macrophages, and T regulator cells to subgroup intrahepatic and distal cholangiocarcinoma, the prognosis is significantly better distinguished. Moreover, PD-L1- M2 tumor-associated macrophages is associated with a good prognosis in intrahepatic and distal cholangiocarcinoma, suggesting this subtype of M2 tumor-associated macrophages may be antitumoral. Interestingly, lower densities of various types of immunosuppressive cells are associated with decreased infiltration of effector T cells in distal and hilar cholangiocarcinoma, but not in intrahepatic cholangiocarcinoma. In intrahepatic cholangiocarcinoma, PD-L1+ tumor-associated macrophages exert their immunosuppressive function likely through promoting T cell exhaustion.

CONCLUSIONS

This study suggests that the densities of Granzyme-B+CD8+ effector T cells and non-exhausted PD-1-EOMES-CD8+ T cells and the PD-L1 status in the tumor-associated macrophages are prognostic makers in cholangiocarcinomas. The study also supports targeting PD-L1+ tumor-associated macrophages as the immunotherapy for cholangiocarcinoma.

Combined arterial and delayed enhancement patterns of MRI assist in prognostic prediction for intrahepatic mass-forming cholangiocarcinoma (IMCC)

OBJECTIVES

This study valued MR delayed enhancement pattern in predicting postoperative prognosis of intrahepatic mass-forming cholangiocarcinoma (IMCC).

METHODS

From 2011 to 2015, 231 patients of IMCC underwent DCE-MRI preoperatively. Enhancement patterns and MRI characteristics were evaluated. Recurrence and mortality data were compared among IMCCs with different enhancement patterns. Prognostic factor analysis was performed using preoperative and postoperative clinical-pathologic factors, as well as imaging findings.

RESULTS

Fifty-six (24.2%), 142 (61.5%) and 33 (14.3%) tumors showed hypo, peripheral rim and diffuse hyper enhancement in AP. Fifty-six (24.2%), 81 (35.1%) and 94 (40.7%) tumors showed hypo, heterogeneous and uniform enhancement in DP. Patients with arterial diffuse hyper enhancement or delayed uniform enhancement IMCCs had lower preoperative CA19-9 levels, smaller tumor sizes and minor operations than the rest patients (p < 0.05) and they were less associated with lymph nodes metastasis, vascular invasion, necrosis or poor tumor differentiation (p < 0.05), therefore with higher overall and disease-free survival rates (p < 0.05). The combination of AP and DP increased the detection rate of patients with good prognosis in the arterial rim enhancement group. Multivariate analysis revealed the delayed enhancement pattern (hypo HR = 6.304/10.028 for DFS/OS; heterogenous HR = 4.579/4.972 for DFS/OS), multitude of lesions (HR = 1.6/1.5 for DFS/OS) and tumor sizes (HR = 1.6 for DFS) were independent prognostic factors.

CONCLUSIONS

The uniform enhancement pattern in delayed MRI was an independent optimal prognostic factor for IMCCs and increased the detection rate of patients with good prognosis compared to the arterial diffuse hyper enhancement pattern.

Cancer Stem Cells in Intrahepatic Cholangiocarcinoma; Their Molecular Basis, and Therapeutic Implications

Cancer tissue consists of heterogenous cell types, and cancer stem cells (CSCs) are a subpopulation of the tissue which possess therapy resistance, tumor reconstruction capability, and are responsible for metastasis. Intrahepatic cholangiocarcinoma (iCCA) is one of the most common type of liver cancer that is highly aggressive with poor prognosis. Since no target therapy is efficient in improving patient outcomes, new therapeutic approaches need to be developed. CSC is thought to be a promising therapeutic target because of its resistance to therapy. Accumulating evidences suggests that there are many factors (surface marker, stemness-related genes, etc.) and mechanisms (epithelial-mesenchymal transition, mitochondria activity, etc.) which are linked to CSC-like phenotypes. Nevertheless, limited studies are reported about the application of therapy using these mechanisms, suggesting that more precise understandings are still needed. In this review, we overview the molecular mechanisms which modulate CSC-like phenotypes, and discuss the future perspective for targeting CSC in iCCA.

Comparison of clinical characteristics and mortality risk between patients with cholangiocarcinoma: A retrospective cohort study

Background

Cholangiocarcinoma (CCA) is primary liver cancer originating from the biliary tract. The epidemiology of CCA is diverse across the globe. There are no reliably effective options for systemic therapy and CCA outcomes are poor. Herein, we examined the association between overall survival and clinical characteristics of CCA patients in our region.

Methods

We included 62 CCA cases diagnosed between 2015 and 2019. Demographics, clinical history, therapeutic procedures, and concomitant diseases were abstracted. Patient survival was obtained from a household registration system.

Results

The cohort was 69% male and 31% female, with 26 (42%) iCCA, 27 (44%) pCCA, and 9 (15%) dCCA. No age differences were observed between the three subtypes. Bile duct and metabolic disorders were the major concomitant diseases and showed varying associations with CCA subgroups. Serum triglycerides (TG) were higher in pCCA and dCCA than iCCA patients (p < 0.05), and TG and total cholesterol (TC) were highest among pCCA patients with cholelithiasis. Liver function appeared significant difference between iCCA, pCCA and dCCA subtypes (p < 0.01), and also in the subgroups without cholelithiasis (p < 0.01). The obstructive jaundice in pCCA patients was associated with survival time after surgery, and the presence of cholelithiasis was also another influential factor.

Conclusion

We found that pCCA was more frequently associated with metabolic disorders compared to iCCA and dCCA. Postoperative survival was also associated with the degree of jaundice in pCCA compared to iCCA or dCCA. And biliary drainage is an important predictor of outcome of pCCA.

Placental growth factor promotes tumour desmoplasia and treatment resistance in intrahepatic cholangiocarcinoma

OBJECTIVE

Intrahepatic cholangiocarcinoma (ICC)-a rare liver malignancy with limited therapeutic options-is characterised by aggressive progression, desmoplasia and vascular abnormalities. The aim of this study was to determine the role of placental growth factor (PlGF) in ICC progression.

DESIGN

We evaluated the expression of PlGF in specimens from ICC patients and assessed the therapeutic effect of genetic or pharmacologic inhibition of PlGF in orthotopically grafted ICC mouse models. We evaluated the impact of PlGF stimulation or blockade in ICC cells and cancer-associated fibroblasts (CAFs) using in vitro 3-D coculture systems.

RESULTS

PlGF levels were elevated in human ICC stromal cells and circulating blood plasma and were associated with disease progression. Single-cell RNA sequencing showed that the major impact of PlGF blockade in mice was enrichment of quiescent CAFs, characterised by high gene transcription levels related to the Akt pathway, glycolysis and hypoxia signalling. PlGF blockade suppressed Akt phosphorylation and myofibroblast activation in ICC-derived CAFs. PlGF blockade also reduced desmoplasia and tissue stiffness, which resulted in reopening of collapsed tumour vessels and improved blood perfusion, while reducing ICC cell invasion. Moreover, PlGF blockade enhanced the efficacy of standard chemotherapy in mice-bearing ICC. Conclusion PlGF blockade leads to a reduction in intratumorous hypoxia and metastatic dissemination, enhanced chemotherapy sensitivity and increased survival in mice-bearing aggressive ICC.

Potential utility of liquid biopsies in the management of patients with biliary tract cancers: A review

Biliary tract cancer, comprising gallbladder cancer, cholangiocarcinoma and ampullary cancer, represents a more uncommon entity outside high-endemic areas, though global incidence is rising. The majority of patients present at a late stage, and 5-year survival remains poor. Advanced stage disease is incurable, and though palliative chemotherapy has been shown to improve survival, further diagnostic and therapeutic options are required in order to improve patient outcomes. Although certain subtypes of biliary tract cancer are relatively rich in targetable mutations, attaining tumour tissue for histological diagnosis and treatment monitoring is challenging due to locoregional anatomical constraints and patient fitness. Liquid biopsies offer a safe and convenient alternative to invasive procedures and have great potential as diagnostic, predictive and prognostic biomarkers. In this review, the current standard of care for patients with biliary tract cancer, future treatment horizons and the possible utility of liquid biopsies within a variety of contexts will be discussed. Circulating tumour DNA, circulating microRNA and circulating tumour cells are discussed with an overview of their potential applications in management of biliary tract cancer. A summary is also provided of currently recruiting clinical trials incorporating liquid biopsies within biliary tract cancer research.

Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a highly lethal adenocarcinoma of the hepatobiliary system, which can be classified as intrahepatic, perihilar and distal. Each anatomic subtype has distinct genetic aberrations, clinical presentations and therapeutic approaches. In endemic regions, liver fluke infection is associated with CCA, owing to the oncogenic effect of the associated chronic biliary tract inflammation. In other regions, CCA can be associated with chronic biliary tract inflammation owing to choledocholithiasis, cholelithiasis, or primary sclerosing cholangitis, but most CCAs have no identifiable cause. Administration of the anthelmintic drug praziquantel decreases the risk of CCA from liver flukes, but reinfection is common and future vaccination strategies may be more effective. Some patients with CCA are eligible for potentially curative surgical options, such as resection or liver transplantation. Genetic studies have provided new insights into the pathogenesis of CCA, and two aberrations that drive the pathogenesis of non-fluke-associated intrahepatic CCA, fibroblast growth factor receptor 2 fusions and isocitrate dehydrogenase gain-of-function mutations, can be therapeutically targeted. CCA is a highly desmoplastic cancer and targeting the tumour immune microenvironment might be a promising therapeutic approach. CCA remains a highly lethal disease and further scientific and clinical insights are needed to improve patient outcomes.

Molecular Oncology of Gall Bladder Cancer

Gall bladder carcinoma (GBC) is a worldwide problem, with a higher incidence in areas of the world where cholelithiasis is common. As GBC is usually diagnosed in an advanced stage, the mortality is high. An understanding of the molecular pathways of carcinogenesis and the mutations involved in the development and progression of GBC could be useful in early diagnosis. Understanding molecular markers of prognosis as well as predictors of outcome could also potentially benefit patients undergoing treatment. New therapies targeting major molecular pathways and immunotherapy are exciting novel therapeutic options. This review focuses on the current understanding of the molecular oncology of GBC.

Long Noncoding RNA GAS5 Accelerates Cholangiocarcinoma Progression by Regulating hsa-miR-1297

Background

Long noncoding RNAs (lncRNAs) have been reported as important molecules in cholangiocarcinoma (CCA) occurrence and development. A previous study showed that lncRNA GAS5 (GAS5) was an oncogene in some tumors. But the role of GAS5 in CCA progression reminds unclear. This research was designed to study the expression and potential effects of GAS5 in the progression of CCA.

Methods

The expression of GAS5 in CCA tissues was evaluated through mining of the TCGA and GEPIA databases. qRT-PCR was applied to validate the results in our clinical samples. χ² test was used to analyze the association between the expression level of tissue GAS5 and different clinicopathological parameters of CCA patients. The target gene of GAS5 was predicted by bioinformatic databases, and further verified by luciferase reporter assays. Finally, the role of GAS5 in CCA cells invasion and proliferation was detected by Transwell assay and CCK-8 assay.

Results

Compared to the adjacent nontumor tissues and the normal human intrahepatic biliary epithelial cell, the expression of GAS5 was markedly increased in CCA tissues (p<0.001) and cell lines (p<0.01), respectively. CCA patients with high GAS5 expression tended to present lymph node metastasis (p<0.001) and had advanced clinical stage (p=0.006). The bioinformatics analysis predicted that hsa-miR-1297 was the potential target gene of GAS5, which was validated by luciferase reporter assays. In addition, the function study showed that GAS5 acted as a “sponge” to downregulate hsa-miR-1297, thus modulating CCA cell proliferation and invasion.

Conclusion

GAS5 acts as an endogenous sponge of hsa-miR-1297 to promote CCA cell proliferation and invasion, which might be a potential biomarker and therapeutic target for CCA.

Metformin exerts anti-cancerogenic effects and reverses epithelial-to-mesenchymal transition trait in primary human intrahepatic cholangiocarcinoma cells

Intrahepatic cholangiocarcinoma (iCCA) is a highly aggressive cancer with marked resistance to chemotherapeutics without therapies. The tumour microenvironment of iCCA is enriched of Cancer-Stem-Cells expressing Epithelial-to-Mesenchymal Transition (EMT) traits, being these features associated with aggressiveness and drug resistance. Treatment with the anti-diabetic drug Metformin, has been recently associated with reduced incidence of iCCA. We aimed to evaluate the anti-cancerogenic effects of Metformin in vitro and in vivo on primary cultures of human iCCA. Our results showed that Metformin inhibited cell proliferation and induced dose- and time-dependent apoptosis of iCCA. The migration and invasion of iCCA cells in an extracellular bio-matrix was also significantly reduced upon treatments. Metformin increased the AMPK and FOXO3 and induced phosphorylation of activating FOXO3 in iCCA cells. After 12 days of treatment, a marked decrease of mesenchymal and EMT genes and an increase of epithelial genes were observed. After 2 months of treatment, in order to simulate chronic administration, Cytokeratin-19 positive cells constituted the majority of cell cultures paralleled by decreased Vimentin protein expression. Subcutaneous injection of iCCA cells previously treated with Metformin, in Balb/c-nude mice failed to induce tumour development. In conclusion, Metformin reverts the mesenchymal and EMT traits in iCCA by activating AMPK-FOXO3 related pathways suggesting it might have therapeutic implications.

Cell of origin in biliary tract cancers and clinical implications

Biliary tract cancers (BTCs) are aggressive epithelial malignancies that can arise at any point of the biliary tree. Albeit rare, their incidence and mortality rates have been rising steadily over the past 40 years, highlighting the need to improve current diagnostic and therapeutic strategies. BTCs show high inter- and intra-tumour heterogeneity both at the morphological and molecular level. Such complex heterogeneity poses a substantial obstacle to effective interventions. It is widely accepted that the observed heterogeneity may be the result of a complex interplay of different elements, including risk factors, distinct molecular alterations and multiple potential cells of origin. The use of genetic lineage tracing systems in experimental models has identified cholangiocytes, hepatocytes and/or progenitor-like cells as the cells of origin of BTCs. Genomic evidence in support of the distinct cell of origin hypotheses is growing. In this review, we focus on recent advances in the histopathological subtyping of BTCs, discuss current genomic evidence and outline lineage tracing studies that have contributed to the current knowledge surrounding the cell of origin of these tumours.

The Tumor Microenvironment in Cholangiocarcinoma Progression

Cholangiocarcinoma (CCA) is an aggressive and heterogeneous malignancy of the biliary tree. A typical hallmark of CCA is that cancer cells are embedded into a dense stroma containing fibrogenic cells, lymphatics and a variety of immune cells. Functional roles of the reactive tumor stroma are not fully elucidated; however, recent studies suggest that the tumor microenvironment plays a key role in the progression and invasiveness of CCA. CCA cells exchange autocrine/paracrine signals with other cancer cells and the infiltrating cell types that populate the microenvironment. This crosstalk is under the control of signals mediated by various cytokines, chemokines, and growth factors. In addition, extracellular vesicles (EVs), exosomes and microvesicles, containing cargo mediators, such as proteins and RNAs, play a key role in cell-to-cell communication, and particularly in epigenetic regulation thanks to their content in miRNAs. Both cytokine- and EV-mediated communications between CCA cells and other liver cells provide a potential novel target for the management of CCA. This review summarizes current understandings of the tumor microenvironment and intercellular communications in CCA and their role in tumor progression.

DCLK1, a Putative Stem Cell Marker in Human Cholangiocarcinoma

BACKGROUND AND AIMS

Cholangiocarcinoma (CCA) is a very aggressive cancer showing the presence of high cancer stem cells (CSCs). Doublecortin-like kinase1 (DCLK1) has been demonstrated as a CSC marker in different gastroenterological solid tumors. Our aim was to evaluate in vitro the expression and the biological function of DCLK1 in intrahepatic CCA (iCCA) and perihilar CCA (pCCA).

APPROACH AND RESULTS

Specimens surgically resected of human CCA were enzymatically digested, submitted to immunosorting for specific CSC markers (LGR5 [leucine-rich repeat-containing G protein-coupled receptor], CD [clusters of differentiation] 90, EpCAM [epithelial cell adhesion molecule], CD133, and CD13), and primary cell cultures were prepared. DCLK1 expression was analyzed in CCA cell cultures by real-time quantitative PCR, western blot, and immunofluorescence. Functional studies have been performed by evaluating the effects of selective DCLK1 inhibitor (LRRK2-IN-1) on cell proliferation (MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay, cell population doubling time), apoptosis, and colony formation capacity. DCLK1 was investigated in situ by immunohistochemistry and real-time quantitative PCR. DCLK1 serum concentration was analyzed by enzyme-linked immunosorbent assay. We describe DCLK1 in CCA with an increased gene and protein DCLK1 expression in pCCA^LGR5+ and in iCCA^CD133+ cells compared with unsorted cells. LRRK2-IN-1 showed an anti-proliferative effect in a dose-dependent manner. LRRK2-IN-1 markedly impaired cell proliferation, induced apoptosis, and decreased colony formation capacity and colony size in both iCCA and pCCA compared with the untreated cells. In situ analysis confirmed that DCLK1 is present only in tumors, and not in healthy tissue. Interestingly, DCLK1 was detected in the human serum samples of patients with iCCA (high), pCCA (high), HCC (low), and cirrhosis (low), but it was almost undetectable in healthy controls.

CONCLUSIONS

DCLK1 characterizes a specific CSC subpopulation of iCCA^CD133+ and pCCA^LGR5+ , and its inhibition exerts anti-neoplastic effects in primary CCA cell cultures. Human DCLK1 serum might represent a serum biomarker for the early CCA diagnosis.

Different iron-handling in inflamed small and large cholangiocytes and in small and large-duct type intrahepatic cholangiocarcinoma

Cholangiocarcinoma (CCA) represents the second most common primary hepatic malignancy and originates from the neoplastic transformation of the biliary cells. The intrahepatic subtype includes two morpho-molecular forms: large-duct type intrahepatic CCA (iCCA) and small-duct type iCCA. Iron is fundamental for the cellular processes, contributing in tumor development and progression. The aim of this study was to evaluate iron uptake, storage, and efflux proteins in both lipopolysaccharide-inflamed small and large cholangiocytes as well as in different iCCA subtypes. Our results show that, despite an increase in interleukin-6 production by both small and large cholangiocytes, ferroportin (Fpn) was decreased only in small cholangiocytes, whereas transferrin receptor-1 (TfR1) and ferritin (Ftn) did not show any change. Differently from in vitro models, Fpn expression was increased in malignant cholangiocytes of small-duct type iCCA in comparison to large-duct type iCCA and peritumoral tissues. TfR1, Ftn and hepcidin were enhanced, even if at different extent, in both malignant cholangiocytes in comparison to the surrounding samples. Lactoferrin was higher in large-duct type iCCA in respect to small-duct type iCCA and peritumoral tissues. These findings show a different iron handling by inflamed small and large cholangiocytes, and small and large-duct type iCCA. The difference in iron homeostasis by the iCCA subtypes may have implications for the tumor management.

Intrahepatic cholangiocarcinomas with IDH1/2 mutation-associated hypermethylation at selective genes and their clinicopathological features

Intrahepatic cholangiocarcinoma (ICC) is a rare but fatal tumor. The isocitrate dehydrogenase 1 and 2 (IDH1/2) genes are known to be mutated in ICC. IDH1/2 mutations tend to be accompanied by enhanced hypermethylation at a subset of genomic loci. We sought to clarify the clinicopathological features, including prognostic value, of ICCs with IDH1/2 mutation-associated hypermethylation at a subset of genes. The mutation status of IDH1/2 and methylation status of 30 gene CpG island loci were analyzed in 172 cases of ICC using pyrosequencing and the MethyLight assay, respectively. The mutation status of IDH1/2 was correlated with clinicopathological features and the DNA methylation status at 30 gene loci. Then, the clinicopathological characteristics were analyzed regarding three-tiered methylation statuses in genes showing IDH1/2 mutation-associated methylation. IDH1/2 mutations were found in 9.3% of ICCs, and IDH1/2-mutated tumors were associated with the histological subtype, including the bile ductular type and small duct type, and poor differentiation. Eight DNA methylation markers showed associations with IDH1/2 mutations, and ICCs with > 5/8 methylated markers were associated with the bile ductular type or small duct type, absence of mucin production, absence of biliary intraepithelial neoplasia, and presence of chronic liver disease. > 5/8 methylated markers were an independent prognostic marker associated with better survival in both cancer-specific survival and recurrence-free survival. In summary, by analyzing the association between IDH1/2 mutations and DNA methylation in individual genes, we developed a panel of DNA methylation markers that were significantly associated with IDH1/2 mutations and were able to identify a subset of ICC with better clinical outcomes.

Targeting Liver Cancer Stem Cells: An Alternative Therapeutic Approach for Liver Cancer

The first report of cancer stem cell (CSC) from Bruce et al. has demonstrated the relatively rare population of stem-like cells in acute myeloid leukemia (AML). The discovery of leukemic CSCs prompted further identification of CSCs in multiple types of solid tumor. Recently, extensive research has attempted to identity CSCs in multiple types of solid tumors in the brain, colon, head and neck, liver, and lung. Based on these studies, we hypothesize that the initiation and progression of most malignant tumors rely largely on the CSC population. Recent studies indicated that stem cell-related markers or signaling pathways, such as aldehyde dehydrogenase (ALDH), CD133, epithelial cell adhesion molecule (EpCAM), Wnt/β-catenin signaling, and Notch signaling, contribute to the initiation and progression of various liver cancer types. Importantly, CSCs are markedly resistant to conventional therapeutic approaches and current targeted therapeutics. Therefore, it is believed that selectively targeting specific markers and/or signaling pathways of hepatic CSCs is an effective therapeutic strategy for treating chemotherapy-resistant liver cancer. Here, we provide an overview of the current knowledge on the hepatic CSC hypothesis and discuss the specific surface markers and critical signaling pathways involved in the development and maintenance of hepatic CSC subpopulations.

Eligibility for Liver Transplantation in Patients with Perihilar Cholangiocarcinoma

BACKGROUND

Liver transplantation (LT) has been performed in a select group of patients presenting with unresectable or primary sclerosing cholangitis (PSC)-associated perihilar cholangiocarcinoma (pCCA) in the Mayo Clinic with a reported 5-year overall survival (OS) of 53% on intention-to-treat analysis. The objective of this study was to estimate eligibility for LT in a cohort of pCCA patients in two tertiary referral centers.

METHODS

Patients diagnosed with pCCA between 2002 and 2014 were included from two tertiary referral centers in the Netherlands. The selection criteria used by the Mayo Clinic were retrospectively applied to determine the proportion of patients that would have been eligible for LT.

RESULTS

A total of 732 consecutive patients with pCCA were identified, of whom 24 (4%) had PSC-associated pCCA. Overall, 154 patients had resectable disease on imaging and 335 patients were ineligible for LT because of lymph node or distant metastases. An age limit of 70 years led to the exclusion of 50 patients who would otherwise be eligible for LT. After applying the Mayo Clinic criteria, only 34 patients (5%) were potentially eligible for LT. Median survival from diagnosis for these 34 patients was 13 months (95% CI 3-23).

CONCLUSION

Only 5% of all patients presenting with pCCA were potentially eligible for LT under the Mayo criteria. Without transplantation, a median OS of about 1 year was observed.

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.

Olaparib and Pembrolizumab Treatment for BRCA1-Mutated and PD-L1-Positive Intrahepatic Cholangiocarcinoma Recurrence and Metastasis: A Case Report

Olaparib has been applied as monotherapy to treat ovarian and breast cancer patients with malignant or suspected malignant BRCA1/2 mutations. Pembrolizumab has been approved to treat unresectable or metastatic tumors in patients who exhibited progression after previous treatment, regardless of histology. However, there are no reports on the use of olaparib and pembrolizumab for the treatment of BRCA1/2-mutated and PD-L1-positive intrahepatic cholangiocarcinoma (iCCA). This case report aimed to observe the safety and efficacy of olaparib and pembrolizumab in treating BRCA1-mutated and PD-L1-positive iCCA recurrence and metastasis. This case report describes a patient with BRCA1-mutated and PD-L1-positive iCCA recurrence and metastases who received olaparib and pembrolizumab. Olaparib (400 mg orally twice daily) and pembrolizumab (100 mg iv every 3 weeks) were administered to the patient for 9 months. The patient achieved complete response (CR) confirmed by liver magnetic resonance imaging (MRI)+ perfusion-weighted imaging (PWI)+ diffusion-weighted imaging (DWI), and the carcinoembryonic antigen (CEA), alpha fetoprotein (AFP), carbohydrate antigen 125 (CA-125), and carbohydrate antigen 199 (CA19-9) tumor marker levels were normal after treatment. There were no significant adverse events, and routine blood counts, coagulation function, and liver and kidney function were normal. The Eastern Cooperative Oncology Group (ECOG) performance status decreased from a score of 1 to a score of 0. Olaparib and pembrolizumab can effectively treat BRCA1-mutated and PD-L1-positive iCCA patients, and adverse effects were largely unobserved. More studies should be performed to promote the development of tumor genomics because the findings from these studies may help clinicians select suitable biomarkers to treat iCCA patients. As the use of immunotherapy alone to treat tumors may not achieve the expected effect, targeted therapy combined with immunotherapy has become a new approach in cancer treatment strategies.

Overexpression of 14-3-3σ Modulates Cholangiocarcinoma Cell Survival by PI3K/Akt Signaling

The protein 14-3-3σ is involved in numerous cellular processes through its ability to bind phosphorylated serine/threonine residues. It is a key regulator of the cell cycle involving in G2 arrest by p53. Deregulation of 14-3-3σ expression has been associated with a large variety of human cancers. However, its physiological function and therapeutic significance have rarely been investigated in cholangiocarcinoma. Using immunohistochemistry (IHC), we evaluated 14-3-3σ expression in 65 human extrahepatic cholangiocarcinomas. As a result, we found that 14-3-3σ is expressed in the tissue of 56 patients (86.2%), and its expression is positively correlated with tumor size, lymph node metastasis, and tumor stage. We also explored the significance of 14-3-3σ and found that 14-3-3σ exerts cell type-dependent effects on cell proliferation through PI3K/Akt signaling in both in vitro and in vivo xenograft models. These results suggest that 14-3-3σ assumes a constitutive role in tumorigenesis rather than acting as a cell cycle regulator in cholangiocarcinoma, which makes 14-3-3σ a new potential target for therapeutic intervention.

First evidence for the antitumor activity of nanoliposomal irinotecan with 5-fluorouracil and folinic acid in metastatic biliary tract cancer

Background

Therapeutic options are limited for advanced, metastatic biliary tract cancer. The pivotal NAPOLI-1 trial demonstrated the superior clinical benefit of nanoliposomal irinotecan (Nal-IRI) in gemcitabine-pretreated patients with metastatic pancreatic ductal adenocarcinoma; however, the antitumor activity of Nal-IRI in biliary tract cancer is unknown. This is the first report describing the efficacy of Nal-IRI in biliary tract cancer.

Methods

In this multicenter retrospective cohort analysis, we identified patients with metastatic biliary tract adenocarcinoma who were treated with Nal-IRI in combination with 5-fluorouracil and folinic acid following tumor progression under standard therapy at one of the study centers between May 2016 and January 2019. We assessed disease control rate (DCR), progression-free survival (PFS), and overall survival (OS).

Results

There were 14 patients; the median age at the time of diagnosis and the median age at the initiation of Nal-IRI were 59.3 and 60.0 years, respectively. Nal-IRI in combination with 5-fluorouracil and folinic acid was administered as second-, third-, fourth-, and fifth-line treatment in 6 (43%), 5 (36%), 2 (14%), and 1 (7%) patient with metastatic disease, respectively. The objective DCR with Nal-IRI was 50% (7/14 patients). Six patients (43%) had partial response, and one patient (7%) had stable disease. Progressive disease was observed in seven patients. The median PFS and median OS following Nal-IRI initiation were 10.6 and 24.1 months, respectively.

Conclusions

This retrospective analysis provides the first evidence that Nal-IRI might exhibit a clinical meaningful antitumor activity in metastatic biliary tract cancer.

Therapeutic Potential of Autophagy Modulation in Cholangiocarcinoma

Autophagy is a multistep catabolic process through which misfolded, aggregated or mutated proteins and damaged organelles are internalized in membrane vesicles called autophagosomes and ultimately fused to lysosomes for degradation of sequestered components. The multistep nature of the process offers multiple regulation points prone to be deregulated and cause different human diseases but also offers multiple targetable points for designing therapeutic strategies. Cancer cells have evolved to use autophagy as an adaptive mechanism to survive under extremely stressful conditions within the tumor microenvironment, but also to increase invasiveness and resistance to anticancer drugs such as chemotherapy. This review collects clinical evidence of autophagy deregulation during cholangiocarcinogenesis together with preclinical reports evaluating compounds that modulate autophagy to induce cholangiocarcinoma (CCA) cell death. Altogether, experimental data suggest an impairment of autophagy during initial steps of CCA development and increased expression of autophagy markers on established tumors and in invasive phenotypes. Preclinical efficacy of autophagy modulators promoting CCA cell death, reducing invasiveness capacity and resensitizing CCA cells to chemotherapy open novel therapeutic avenues to design more specific and efficient strategies to treat this aggressive cancer.

Multifaceted Aspects of Metabolic Plasticity in Human Cholangiocarcinoma: An Overview of Current Perspectives

Cholangiocarcinoma (CCA) is a deadly tumor without an effective therapy. Unique metabolic and bioenergetics features are important hallmarks of tumor cells. Metabolic plasticity allows cancer cells to survive in poor nutrient environments and maximize cell growth by sustaining survival, proliferation, and metastasis. In recent years, an increasing number of studies have shown that specific signaling networks contribute to malignant tumor onset by reprogramming metabolic traits. Several evidences demonstrate that numerous metabolic mediators represent key-players of CCA progression by regulating many signaling pathways. Besides the well-known Warburg effect, several other different pathways involving carbohydrates, proteins, lipids, and nucleic acids metabolism are altered in CCA. The goal of this review is to highlight the main metabolic processes involved in the cholangio-carcinogeneis that might be considered as potential novel druggable candidates for this disease.

Cholest-4,6-Dien-3-One Promote Epithelial-To-Mesenchymal Transition (EMT) in Biliary Tree Stem/Progenitor Cell Cultures In Vitro

Human biliary tree stem/progenitor cells (hBTSCs), reside in peribiliary glands, are mainly stimulated by primary sclerosing cholangitis (PSC) and cholangiocarcinoma. In these pathologies, hBTSCs displayed epithelial-to-mesenchymal transition (EMT), senescence characteristics, and impaired differentiation. Here, we investigated the effects of cholest-4,6-dien-3-one, an oxysterol involved in cholangiopathies, on hBTSCs biology. hBTSCs were isolated from donor organs, cultured in self-renewal control conditions, differentiated in mature cholangiocytes by specifically tailored medium, or exposed for 10 days to concentration of cholest-4,6-dien-3-one (0.14 mM). Viability, proliferation, senescence, EMT genes expression, telomerase activity, interleukin 6 (IL6) secretion, differentiation capacity, and HDAC6 gene expression were analyzed. Although the effect of cholest-4,6-dien-3-one was not detected on hBTSCs viability, we found a significant increase in cell proliferation, senescence, and IL6 secretion. Interestingly, cholest-4.6-dien-3-one impaired differentiation in mature cholangiocytes and, simultaneously, induced the EMT markers, significantly reduced the telomerase activity, and induced HDAC6 gene expression. Moreover, cholest-4,6-dien-3-one enhanced bone morphogenic protein 4 (Bmp-4) and sonic hedgehog (Shh) pathways in hBTSCs. The same pathways activated by human recombinant proteins induced the expression of EMT markers in hBTSCs. In conclusion, we demonstrated that chronic exposition of cholest-4,6-dien-3-one induced cell proliferation, EMT markers, and senescence in hBTSC, and also impaired the differentiation in mature cholangiocytes.

Common features between neoplastic and preneoplastic lesions of the biliary tract and the pancreas

the bile duct system and pancreas show many similarities due to their anatomical proximity and common embryological origin. Consequently, preneoplastic and neoplastic lesions of the bile duct and pancreas share analogies in terms of molecular, histological and pathophysiological features. Intraepithelial neoplasms are reported in biliary tract, as biliary intraepithelial neoplasm (BilIN), and in pancreas, as pancreatic intraepithelial neoplasm (PanIN). Both can evolve to invasive carcinomas, respectively cholangiocarcinoma (CCA) and pancreatic ductal adenocarcinoma (PDAC). Intraductal papillary neoplasms arise in biliary tract and pancreas. Intraductal papillary neoplasm of the biliary tract (IPNB) share common histologic and phenotypic features such as pancreatobiliary, gastric, intestinal and oncocytic types, and biological behavior with the pancreatic counterpart, the intraductal papillary mucinous neoplasm of the pancreas (IPMN). All these neoplastic lesions exhibit similar immunohistochemical phenotypes, suggesting a common carcinogenic process. Indeed, CCA and PDAC display similar clinic-pathological features as growth pattern, poor response to conventional chemotherapy and radiotherapy and, as a consequence, an unfavorable prognosis. The objective of this review is to discuss similarities and differences between the neoplastic lesions of the pancreas and biliary tract with potential implications on a common origin from similar stem/progenitor cells.

Integrative Analysis Defines Distinct Prognostic Subgroups of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver cancer. It is defined by cholangiocytic differentiation and has poor prognosis. Recently, epigenetic processes have been shown to play an important role in cholangiocarcinogenesis. We performed an integrative analysis on 52 iCCAs using both genetic and epigenetic data with a specific focus on DNA methylation components. We found recurrent isocitrate dehydrogenase 1 (IDH1) and IDH2 (28%) gene mutations, recurrent arm-length copy number alterations (CNAs), and focal alterations such as deletion of 3p21 or amplification of 12q15, which affect BRCA1 Associated Protein 1, polybromo 1, and mouse double minute 2 homolog. DNA methylome analysis revealed excessive hypermethylation of iCCA, affecting primarily the bivalent genomic regions marked with both active and repressive histone modifications. Integrative clustering of genetic and epigenetic data identified four iCCA subgroups with prognostic relevance further designated as IDH, high (H), medium (M), and low (L) alteration groups. The IDH group consisted of all samples with IDH1 or IDH2 mutations and showed, together with the H group, a highly disrupted genome, characterized by frequent deletions of chromosome arms 3p and 6q. Both groups showed excessive hypermethylation with distinct patterns. The M group showed intermediate characteristics regarding both genetic and epigenetic marks, whereas the L group exhibited few methylation changes and mutations and a lack of CNAs. Methylation-based latent component analysis of cell-type composition identified differences among these four groups. Prognosis of the H and M groups was significantly worse than that of the L group. Conclusion: Using an integrative genomic and epigenomic analysis approach, we identified four major iCCA subgroups with widespread genomic and epigenomic differences and prognostic implications. Furthermore, our data suggest differences in the cell-of-origin of the iCCA subtypes.

Role of the Angiogenic Factors in Cholangiocarcinoma

Angiogenesis plays a fundamental role in tumor growth and progression. It is regulated by several growth factors, including vascular endothelial growth factor protein family (VEGF) and its receptors, which are probably the most important factors responsible for the development of new vessels. The VEGF family includes several members: VEGF-A, VEGF-B, VEGF-C, VEGF-D, VEGF-E, placental growth factor (PlGF), and their receptors VEGFR-1, VEGFR-2 and VEGFR-3. Other relevant factors are represented by angiopoietins, thrombospondin-1, and endothelins. However, since the therapeutic benefit associated with VEGF-targeted therapy is really complex, a better understanding of these pathways will lead to future advances in the use of these agents for clinic management of tumors. Here we present a review regarding the role of angiogenic factors in cholangiocarcinoma, which arise from cholangiocytes, the epithelial cells of bile ducts. They are rare and aggressive neoplasms with a poor prognosis and limited treatment options, classified as intrahepatic, perihilar, and distal cholangiocarcinoma based on their anatomical location. Therefore, the identification of specific signaling pathways or new tumor biomarkers is crucial in order to develop more effective anti-angiogenic therapies.

Molecular Pathogenesis of Cholangiocarcinoma

BACKGROUND

Cholangiocarcinomas are a heterogeneous group of malignancies arising from a number of cells of origin along the biliary tree. Although most cases in Western countries are sporadic, large population-based studies have identified a number of risk factors. This review summarises the evidence behind reported risk factors and current understanding of the molecular pathogenesis of cholangiocarcinoma, with a focus on inflammation and cholestasis as the driving forces in cholangiocarcinoma development.

RISK FACTORS FOR CHOLANGIOCARCINOGENESIS

Cholestatic liver diseases (e.g. primary sclerosing cholangitis and fibropolycystic liver diseases), liver cirrhosis, and biliary stone disease all increase the risk of cholangiocarcinoma. Certain bacterial, viral or parasitic infections such as hepatitis B and C and liver flukes also increase cholangiocarcinoma risk. Other risk factors include inflammatory disorders (such as inflammatory bowel disease and chronic pancreatitis), toxins (e.g. alcohol and tobacco), metabolic conditions (diabetes, obesity and non-alcoholic fatty liver disease) and a number of genetic disorders.

MOLECULAR PATHOGENESIS OF CHOLANGIOCARCINOMA

Regardless of aetiology, most risk factors cause chronic inflammation or cholestasis. Chronic inflammation leads to increased exposure of cholangiocytes to the inflammatory mediators interleukin-6, Tumour Necrosis Factor-ɑ, Cyclo-oxygenase-2 and Wnt, resulting in progressive mutations in tumour suppressor genes, proto-oncogenes and DNA mismatch-repair genes. Accumulating bile acids from cholestasis lead to reduced pH, increased apoptosis and activation of ERK1/2, Akt and NF-κB pathways that encourage cell proliferation, migration and survival. Other mediators upregulated in cholangiocarcinoma include Transforming Growth Factor-β, Vascular Endothelial Growth Factor, Hepatocyte Growth Factor and several microRNAs. Increased expression of the cell surface receptor c-Met, the glucose transporter GLUT-1 and the sodium iodide symporter lead to tumour growth, angiogenesis and cell migration. Stromal changes are also observed, resulting in alterations to the extracellular matrix composition and recruitment of fibroblasts and macrophages that create a microenvironment promoting cell survival, invasion and metastasis.

CONCLUSION

Regardless of aetiology, most risk factors for cholangiocarcinoma cause chronic inflammation and/or cholestasis, leading to the activation of common intracellular pathways that result in reactive cell proliferation, genetic/epigenetic mutations and cholangiocarcinogenesis. An understanding of the molecular pathogenesis of cholangiocarcinoma is vital when developing new diagnostic biomarkers and targeted therapies for this disease.

A case of intrahepatic cholangiocarcinoma that was difficult to diagnose prior to surgery: A case report

The present study reports a case of mass-forming intrahepatic cholangiocarcinoma (ICC), which mimicked cholangiocellular carcinoma (CoCC) during imaging and a needle biopsy examination. A 51-year-old female with no relevant medical history was referred to the National Defense Medical College hospital with an intrahepatic tumor. Computed tomography demonstrated non-homogeneous enhancement in the early arterial phase and persistent enhancement in the portal and equilibrium phases, together with notable swelling of the para-aortic lymph nodes. Gadolinium-ethoxybenzyl diethylenetriamine-pentaacetic acid-enhanced magnetic resonance imaging revealed low signal intensity in the hepatobiliary phase. The liver tumor and lymph nodes exhibited increased radiotracer uptake (maximum standardized uptake value=14.0) with positron emission tomography. A histological examination of a percutaneous needle biopsy specimen of the liver tumor indicated a diagnosis of CoCC. The patient underwent left hepatectomy and lymphadenectomy. The surgical specimen contained a poorly differentiated adenocarcinoma with anaplastic changes, which was immunohistochemically positive for epithelial membrane antigen (at the luminal membrane), cytokeratins 7 and 19, and negative for α-fetoprotein, hepatocyte-specific antigen, cluster of differentiation 56 and KIT. Based on these histopathological and immunohistochemical findings, the patient was diagnosed with ICC.