UNASSIGNED: Global liquid chromatography mass spectrometry (LC-MS) profiling in a Thai population has previously identified a urinary metabolic signature in Opisthorchis viverrini-induced cholangiocarcinoma (CCA), primarily characterised by disturbance in acylcarnitine, bile acid, steroid, and purine metabolism. However, the detection of thousands of analytes by LC-MS in a biological sample in a single experiment potentially introduces false discovery errors. To verify these observed metabolic perturbations, a second validation dataset from the same population was profiled in a similar fashion.
UNASSIGNED: Reverse-phase ultra-performance liquid-chromatography mass spectrometry was utilised to acquire the global spectral profile of 98 spot urine samples (from 46 healthy volunteers and 52 CCA patients) recruited from Khon Kaen, northeast Thailand (the highest incidence of CCA globally).
UNASSIGNED: Metabolites were differentially expressed in the urinary profiles from CCA patients. High urinary elimination of bile acids was affected by the presence of obstructive jaundice. The urine metabolome associated with non-jaundiced CCA patients showed a distinctive pattern, similar but not identical to published studies. A panel of 10 metabolites achieved a diagnostic accuracy of 93.4% and area under the curve value of 98.8% (CI = 96.3%-100%) for the presence of CCA.
UNASSIGNED: Global characterisation of the CCA urinary metabolome identified several metabolites of biological interest in this validation study. Analyses of the diagnostic utility of the discriminant metabolites showed excellent diagnostic potential. Further larger scale studies are required to confirm these findings internationally, particularly in comparison to sporadic CCA, not associated with liver fluke infestation.

UNASSIGNED: Biliary tract cancer (BTC) is associated with a dismal prognosis, partly because it is typically diagnosed late, highlighting the need for diagnostic biomarkers. The purpose of this project was to identify and validate multiprotein signatures that could differentiate patients with BTC from non-cancer controls.
UNASSIGNED: In this study, we included treatment-naïve patients with BTC, healthy controls, and patients with benign conditions including benign biliary tract disease. Participants were divided into three non-overlapping cohorts: a case-control-based discovery cohort (BTC = 186, controls = 249); a case-control-based validation cohort (validation cohort 1: BTC = 113, controls = 241); and a cohort study-based validation cohort including participants (BTC = 8, controls = 132) referred for diagnostic work-up for suspected cancer (validation cohort 2). Immuno-Oncology (I-O)-related proteins were measured in serum and plasma using a proximity extension assay (Olink Proteomics). Lasso and Ridge regressions were used to generate protein signatures of I-O-related proteins and carbohydrate antigen 19-9 (CA19-9) in the discovery cohort.
UNASSIGNED: Sixteen protein signatures, including 2 to 82 proteins, were generated. All signatures included CA19-9 and chemokine C-C motif ligand 20. Signatures discriminated between patients with BTC vs. controls, with AUCs ranging from 0.95 to 0.99 in the discovery cohort and 0.94 to 0.97 in validation cohort 1. In validation cohort 2, AUCs ranged from 0.84 to 0.94. Nine signatures achieved a specificity of 82% to 84% while keeping a sensitivity of 100% in validation cohort 2. All signatures performed better than CA19-9, and signatures including >15 proteins showed the best performance.
UNASSIGNED: The study demonstrated that it is possible to generate protein signatures that can successfully differentiate patients with BTC from non-cancer controls.
UNASSIGNED: We attempted to find blood sample-based protein profiles that could differentiate patients with biliary tract cancer from those without cancer. Several profiles were found and tested in different groups of patients. The profiles were successful at identifying most patients with biliary tract cancer, pointing towards the utility of multiprotein signatures in this context.

UNASSIGNED: Liver transplantation (LT) for primary sclerosing cholangitis (PSC) is complicated by recurrence of PSC (rPSC) in up to 25% of recipients. Recurrence has been shown to be detrimental for both graft and patient survival. For both PSC and rPSC, a medical cure is not available. To predict and ideally to prevent rPSC, it is imperative to find risk factors for rPSC that can be potentially modified. Therefore, we aimed to identify such factors for rPSC in a large international multicentre study including 6 centres in PSC-prevalent countries.
UNASSIGNED: In this international multicentre, retrospective cohort study, 531 patients who underwent transplantation for PSC were included. In 25% of cases (n = 131), rPSC was diagnosed after a median follow-up of 6.72 (3.29-10.11) years post-LT.
UNASSIGNED: In the multivariable competing risk model with time-dependent covariates, we found that factors representing an increased inflammatory state increase the risk for rPSC. Recurrent cholangitis before LT as indication for LT (hazard ratio [HR] 3.6, 95% CI 2.5-5.2), increased activity of inflammatory bowel disease after LT (HR 1.7, 95% CI 1.08-2.75), and multiple acute cellular rejections (HR: non-linear) were significantly and independently associated with an increased risk of rPSC. In contrast to the findings of previous studies, pretransplant colectomy was not found to be independently protective against the development of rPSC.
UNASSIGNED: An increased inflammatory state before and after LT may play a causal and modifiable role in the development of rPSC. Pretransplant colectomy did not reduce the risk of rPSC per se. Recurrent cholangitis as indication for LT was associated with an increased risk of rPSC.
UNASSIGNED: Recurrence of PSC (rPSC) negatively affects survival after liver transplant (LT). Modifiable risk factors could guide clinical management and prevention of rPSC. We demonstrate that an increased inflammatory state both before and after LT increases the incidence of rPSC. As these are modifiable factors, they could serve as targets for future studies and therapies. We also added further evidence to the ongoing debate regarding preventive colectomy for rPSC by reporting that in our multicenter study, we could not find an independent association between colectomy and risk of rPSC.

Lipids are a complex and diverse group of molecules with crucial roles in many physiological processes, as well as in the onset, progression, and maintenance of cancers. Fatty acids and cholesterol are the building blocks of lipids, orchestrating these crucial metabolic processes. In the liver, lipid alterations are prevalent as a cause and consequence of chronic hepatitis B and C virus infections, alcoholic hepatitis, and non-alcoholic fatty liver disease and steatohepatitis. Recent developments in lipidomics have also revealed that dynamic changes in triacylglycerols, phospholipids, sphingolipids, ceramides, fatty acids, and cholesterol are involved in the development and progression of primary liver cancer. Accordingly, the transcriptional landscape of lipid metabolism suggests a carcinogenic role of increasing fatty acids and sterol synthesis. However, limited mechanistic insights into the complex nature of the hepatic lipidome have so far hindered the development of effective therapies.

Hepatocellular carcinoma and cholangiocarcinoma are the most common primary liver tumours, whose incidence and associated mortality have increased over recent decades. Liver cancer is often diagnosed late when curative treatments are no longer an option. Characterising new molecular determinants of liver carcinogenesis is crucial for the development of innovative treatments and clinically relevant biomarkers. Recently, circular RNAs (circRNAs) emerged as promising regulatory molecules involved in cancer onset and progression. Mechanistically, circRNAs are mainly known for their ability to sponge and regulate the activity of microRNAs and RNA-binding proteins, although other functions are emerging (e.g. transcriptional and post-transcriptional regulation, protein scaffolding). In liver cancer, circRNAs have been shown to regulate tumour cell proliferation, migration, invasion and cell death resistance. Their roles in regulating angiogenesis, genome instability, immune surveillance and metabolic switching are emerging. Importantly, circRNAs are detected in body fluids. Due to their circular structure, circRNAs are often more stable than mRNAs or miRNAs and could therefore serve as promising biomarkers - quantifiable with high specificity and sensitivity through minimally invasive methods. This review focuses on the role and the clinical relevance of circRNAs in liver cancer, including the development of innovative biomarkers and therapeutic strategies.

Cholangiocarcinoma (CCA) has emerged as an intractable cancer with scanty therapeutic regimens. The aberrant activation of Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) are reported to be common in CCA patients. However, the underpinning mechanism remains poorly understood. Deubiquitinase (DUB) is regarded as a main orchestrator in maintaining protein homeostasis. Here, we identified Josephin domain-containing protein 2 (JOSD2) as an essential DUB of YAP/TAZ that sustained the protein level through cleavage of polyubiquitin chains in a deubiquitinase activity-dependent manner. The depletion of JOSD2 promoted YAP/TAZ proteasomal degradation and significantly impeded CCA proliferation in vitro and in vivo. Further analysis has highlighted the positive correlation between JOSD2 and YAP abundance in CCA patient samples. Collectively, this study uncovers the regulatory effects of JOSD2 on YAP/TAZ protein stabilities and profiles its contribution in CCA malignant progression, which may provide a potential intervention target for YAP/TAZ-related CCA patients.

UNASSIGNED: Cholangioscopy is useful in establishing a visual diagnosis of cholangiocarcinoma (CCA), but this is harder to achieve in primary sclerosing cholangitis (PSC) because of the stricture-forming nature of the disease. Furthermore, it can be harder to differentiate malignant from benign features of the underlying inflammation. This case series demonstrates the varied features of nonmalignant inflammatory findings in PSC.
UNASSIGNED: A single experienced endoscopist performed cholangioscopy for PSC cases referred for ERCP.
UNASSIGNED: Cholangioscopy in these 5 cases without CCA demonstrated the features of acute and chronic inflammation, acute inflammatory mass, dominant stricture, acute cholangitis in a duct with features of chronic inflammation with a large pigmented stone, and fibrostenotic disease. Cholangioscopic maneuvers such as advancement across strictures after balloon dilation, targeted mucosal biopsy, and electrohydraulic lithotripsy (EHL) of impacted stones are demonstrated. The relevant radiographic and histopathologic features of the disease accompany each case description. Regarding long-term prognosis, 1 case of acute inflammatory mass and a case of worsening liver function required a liver transplant evaluation, whereas the other 3 cases remain stable.
UNASSIGNED: Cholangioscopic features of benign disease in PSC are varied. Knowledge of these features is essential in differentiating between benign and malignant findings. These features, combined with biopsy and cytology evaluation, can help in tailoring management in patients with benign PSC.

UNASSIGNED: Long-term survival of liver transplant recipients is endangered by tumorigenesis at different sites. Little is known about primary de novo tumors developing in the graft.
UNASSIGNED: We analyzed the follow-up data of 2731 liver recipients that were transplanted between 1988 and 2019 at our institution (Charité - Universitätsmedizin Berlin, Department of Surgery). All cases with new intrahepatic tumors during follow-up were identified.
UNASSIGNED: A total of nine patients were diagnosed at a median of 16 years (range, 2-24 years) after surgery. Eight patients presented with hepatocellular carcinoma (HCC), and one patient presented with epithelioid hemangioendothelioma (EHE). All eight HCC patients had a recurrence of the initial disease that had caused liver failure before transplantation. This was associated with viral reinfection with either HCV or HBV in seven cases. Of the nine patients, three underwent surgical resection and only one patient was alive at data abstraction.
UNASSIGNED: Intrahepatic de novo neoplasms in the liver graft need to be considered in the long-term follow-up of liver recipients and were strongly associated with recurrent viral hepatitis in our study. Although prognosis of this rare complication is generally poor, patients may benefit from surgical resection of localized disease.

The family of vascular endothelial growth factors (VEGFs) includes 5 members (VEGF-A to -D, and placenta growth factor), which regulate several critical biological processes. VEGF-A exerts a variety of biological effects through high-affinity binding to tyrosine kinase receptors (VEGFR-1, -2 and -3), co-receptors and accessory proteins. In addition to its fundamental function in angiogenesis and endothelial cell biology, VEGF/VEGFR signalling also plays a role in other cell types including epithelial cells. This review provides an overview of VEGF signalling in biliary epithelial cell biology in both normal and pathologic conditions. VEGF/VEGFR-2 signalling stimulates bile duct proliferation in an autocrine and paracrine fashion. VEGF/VEGFR-1/VEGFR-2 and angiopoietins are involved at different stages of biliary development. In certain conditions, cholangiocytes maintain the ability to secrete VEGF-A, and to express a functional VEGFR-2 receptor. For example, in polycystic liver disease, VEGF secreted by cystic cells stimulates cyst growth and vascular remodelling through a PKA/RAS/ERK/HIF1α-dependent mechanism, unveiling a new level of complexity in VEFG/VEGFR-2 regulation in epithelial cells. VEGF/VEGFR-2 signalling is also reactivated during the liver repair process. In this context, pro-angiogenic factors mediate the interactions between epithelial, mesenchymal and inflammatory cells. This process takes place during the wound healing response, however, in chronic biliary diseases, it may lead to pathological neo-angiogenesis, a condition strictly linked with fibrosis progression, the development of cirrhosis and related complications, and cholangiocarcinoma. Novel observations indicate that in cholangiocarcinoma, VEGF is a determinant of lymphangiogenesis and of the immune response to the tumour. Better insights into the role of VEGF signalling in biliary pathophysiology might help in the search for effective therapeutic strategies.

UNASSIGNED: Prompt and accurate differentiation of benign and malignant strictures in primary sclerosing cholangitis (PSC) is crucial. ERCP with brush cytology, the most common modality to achieve this, is hindered by a low diagnostic yield. Cholangioscopy can overcome this limitation by establishing a visual diagnosis based on the characteristic morphologic features of cholangiocarcinoma (CCA) and can aid in targeted biopsies of suspicious lesions. However, its role in PSC remains unclear. This case series demonstrates the performance of the latest generation of single-operator cholangioscope for this indication.
UNASSIGNED: A single experienced endoscopist performed cholangioscopy for PSC cases referred for ERCP.
UNASSIGNED: Cholangioscopies of patients 1 to 3 demonstrate the features of extrahepatic duct dominant strictures (DS) and the cholangioscopic maneuvers undertaken in these cases, including advancement across the DS after balloon dilation, biopsy of the DS, and electrohydraulic lithotripsy of impacted stones. Cholangioscopies of patients 4 to 6 demonstrate the varied features of CCA ranging from focal stricture with tumor vessels, papillary frond-like projections, and features of an intraductal papillary biliary neoplasm. Also shown are the radiographic and histopathologic features of the disease.
UNASSIGNED: Cholangioscopy allowed us to identify morphologic features of both malignancy and benign disease in PSC in the setting of extrahepatic duct strictures, and we were able to obtain adequate targeted tissue samples for histopathologic confirmation.