Evaluation of soluble suppression of tumorigenicity 2 (sST2) as serum marker for liver fibrosis.

BACKGROUND & AIMS: With the increase in patients at risk of advanced liver disease due to the obesity epidemic, there will be a need for simple screening tools for advanced liver fibrosis. Soluble suppression of tumorigenicity 2 (sST2) is a serum biomarker for fibrotic processes. The aim of this study was to evaluate sST2 as marker for liver fibrosis in patients successfully treated for chronic hepatitis C. METHODS: 424 patients from the Swiss Hepatitis C Cohort Study were screened for inclusion in this post-hoc cohort study. Inclusion criteria were sustained virological response (SVR), available elastography (VCTE) and serum samples for biomarker analysis before and after treatment. For the validation of sST2, values were compared to VCTE, FIB-4 and APRI using Spearman's correlation and AUROC analyses. RESULTS: Data of 164 subjects were finally analyzed. Median sST2 values slightly increased with VCTE-derived fibrosis stages and remained stable after reaching SVR within the respective fibrosis stage, suggesting that sST2 is not influenced by liver inflammation. However, correlation of sST2 pre- and post-treatment with VCTE was fair (Spearman's rho = 0.39 and rho = 0.36). The area under the curve (AUROC) for sST2 in detecting VCTE-defined F4 fibrosis (vs. F0-F3) before therapy was 0.74 (95%CI 0.65-0.83), and 0.67(95%CI 0.56-0.78) for the discrimination of F3/F4 fibrosis vs. F0-F2. Adding sST2 to either APRI or FIB-4, respectively, increased diagnostic performance of both tests. CONCLUSIONS: sST2 can potentially identify patients with advanced fibrosis as a single serum marker and in combination with APRI and FIB-4.

Prognosis of patients with hepatocellular carcinoma treated with immunotherapy - development and validation of the CRAFITY score.

BACKGROUND & AIMS: Immunotherapy with atezolizumab plus bevacizumab represents the new standard of care in systemic front-line treatment of hepatocellular carcinoma (HCC). However, biomarkers that predict treatment success and survival remain an unmet need. METHODS: Patients with HCC put on PD-(L)1-based immunotherapy were included in a training set (n = 190; 6 European centers) and a validation set (n = 102; 8 European centers). We investigated the prognostic value of baseline variables on overall survival using a Cox model in the training set and developed the easily applicable CRAFITY (CRP and AFP in ImmunoTherapY) score. The score was validated in the independent, external cohort, and evaluated in a cohort of patients treated with sorafenib (n = 204). RESULTS: Baseline serum alpha-fetoprotein ≥100 ng/ml (hazard ratio [HR] 1.7; p = 0.007) and C-reactive protein ≥1 mg/dl (HR, 1.7; p = 0.007) were identified as independent prognostic factors in multivariable analysis and were used to develop the CRAFITY score. Patients who fulfilled no criterion (0 points; CRAFITY-low) had the longest median overall survival (27.6 (95% CI 19.5-35.8) months), followed by those fulfilling 1 criterion (1 point; CRAFITY-intermediate; 11.3 (95% CI 8.0-14.6) months), and patients meeting both criteria (2 points; CRAFITY-high; 6.4 (95% CI 4.8-8.1) months; p <0.001). Additionally, best radiological response (complete response/partial response/stable disease/progressive disease) was significantly better in patients with lower CRAFITY score (CRAFITY-low: 9%/20%/52%/20% vs. CRAFITY-intermediate: 3%/25%/36%/36% vs. CRAFITY-high: 2%/15%/22%/61%; p = 0.003). These results were confirmed in the independent validation set and in different subgroups, including Child-Pugh A and B, performance status 0 and ≥1, and first-line and later lines. In the sorafenib cohort, CRAFITY was associated with survival, but not radiological response. CONCLUSIONS: The CRAFITY score is associated with survival and radiological response in patients receiving PD-(L)1 immunotherapy. The score may help with patient counseling but requires prospective validation. LAY SUMMARY: The immunotherapy-based regimen of atezolizumab plus bevacizumab represents the new standard of care in systemic first-line therapy of hepatocellular carcinoma (HCC). Biomarkers to predict treatment outcome are an unmet need in patients undergoing immunotherapy for HCC. We developed and externally validated a score that predicts outcome in patients with HCC undergoing immunotherapy with immune checkpoint blockers.

Carboxypeptidase U (TAFIa) Is Rapidly Activated and Deactivated Following Thrombolysis and Thrombectomy in Stroke Patients.

The antifibrinolytic enzyme carboxypeptidase U (CPU, TAFIa, CPB2) is an appealing target for the treatment of acute ischemic stroke (AIS). Increased insights in CPU activation and inactivation during thrombolysis (rtPA) with or without endovascular thrombectomy (EVT) are required to develop CPU inhibitors as profibrinolytic agents with optimal benefits/risks. Therefore, CPU kinetics during ischemic stroke treatment were evaluated. AIS patients with documented cerebral artery occlusion receiving rtPA (N = 20) or rtPA + EVT (N = 16) were included. CPU activation during thrombolysis was measured by an ultrasensitive HPLC-based CPU activity method and by an ELISA measuring both CPU and inactivated CPU (CPU + CPUi). Intravenous blood samples were collected at admission and throughout the first 24 h. Additional in situ blood samples were collected in the rtPA + EVT cohort proximal from the thrombus. The NIHSS score was determined at baseline and 24 h. CPU activity and CPU + CPUi levels increased upon rtPA administration and reached peak values at the end of thrombolysis (1 h). High inter-individual variability was observed in both groups. CPU activity decreased rapidly within 3 h, while CPU + CPUi levels were still elevated at 7 h. CPU activity or CPU + CPUi levels were similar in in situ and peripheral samples. No correlation between CPU or CPU + CPUi and NIHSS or thrombus localization was found. The CPU system was rapidly activated and deactivated following thrombolysis and thrombectomy in stroke patients, suggesting that a CPU inhibitor would have to be administered during rtPA infusion and over the next few hours. The high CPU generation variability suggests that some patients may not respond to the treatment. EudraCT number 2017-002760-41.

Pleiotropic Effects of Atorvastatin Result in a Downregulation of the Carboxypeptidase U System (CPU, TAFIa, CPB2) in a Mouse Model of Advanced Atherosclerosis.

Statins (hydroxymethyl-glutaryl-CoA-reductase inhibitors) lower procarboxypeptidase U (proCPU, TAFI, proCPB2). However, it is challenging to prove whether this is a lipid or non-lipid-related pleiotropic effect, since statin treatment decreases cholesterol levels in humans. In apolipoprotein E-deficient mice with a heterozygous mutation in the fibrillin-1 gene (ApoE-/-Fbn1C1039G+/-), a model of advanced atherosclerosis, statins do not lower cholesterol. Consequently, studying cholesterol-independent effects of statins can be achieved more straightforwardly in these mice. Female ApoE -/-Fbn1C1039G+/- mice were fed a Western diet (WD). At week 10 of WD, mice were divided into a WD group (receiving WD only) and a WD + atorvastatin group (receiving 10 mg/kg/day atorvastatin +WD) group. After 15 weeks, blood was collected from the retro-orbital plexus, and the mice were sacrificed. Total plasma cholesterol and C-reactive protein (CRP) were measured with commercially available kits. Plasma proCPU levels were determined with an activity-based assay. Total plasma cholesterol levels were not significantly different between both groups, while proCPU levels were significantly lower in the WD + atorvastatin group. Interestingly proCPU levels correlated with CRP and circulating monocytes. In conclusion, our results confirm that atorvastatin downregulates proCPU levels in ApoE-/-Fbn1C1039G+/- mice on a WD, and evidence was provided that this downregulation is a pleiotropic effect of atorvastatin treatment.

Rates of Hepatocellular Carcinoma After Start of Treatment for Chronic Hepatitis C Remain High with Direct Acting Antivirals: Analysis from a Swiss Liver Transplant Center.

BACKGROUND: Direct-acting antivirals (DAA) have revolutionized the therapy of chronic hepatitis C (CHC) and have replaced previous PEG-interferon/ribavirin (PEG-IFN/RBV) treatment. Patients with CHC and advanced liver disease are at increased risk for hepatocellular carcinoma (HCC). However, the effects of DAA-based CHC treatment on subsequent HCC incidence remain poorly understood. PATIENTS AND METHODS: This retrospective single-institution cohort study included 243 consecutive patients after PEG-IFN/RBV and 263 patients after DAA treatment. Multivariable cause-specific Cox proportional hazards models were used to compare time to HCC between treatment types, censoring patients who died or had an orthotopic liver transplantation (OLT) at the time of the competing event. Age, gender, BMI, viral load, cirrhosis, fibrosis stage, diabetes, virus genotype and previous PEG-IFN/RBV (before DAA) were used as covariates. In addition, we performed a propensity score-matched analysis. RESULTS: Nineteen HCC cases were observed after DAA therapy compared to 18 cases after PEG-IFN/RBV treatment. Patients were followed for a median of 4.1 years (IQR: 3.5-4.7) for DAA and 9.3 years (IQR: 6.6-12.4) for the PEG-IFN/RBV group. In an unadjusted Cox model, a hazard ratio (HR) of 6.40 (CI: 2.20-18.61, p=0.006) for HCC following DAA vs PEG-IFN/RBV was estimated. In multivariable Cox proportional hazard models, age and liver cirrhosis were identified as further HCC risk factors but the HR estimates for DAA vs PEG-IFN/RBV still indicate a considerably increased hazard associated with DAA treatment (HR between 7.23 and 11.52, p≤0.001, depending on covariates). A HR of 6.62 (CI: 2.01-21.84, p=0.002) for DAA vs PEG-IFN/RBV was estimated in the propensity score-matched analysis. The secondary outcomes death and OLT did not differ between treatment groups. CONCLUSION: In a cohort study from a tertiary care hospital rates of HCC after the start of DAA treatment were higher compared to PEG-IFN/RBV treatment. Our data reinforce the recommendation that surveillance should be continued after successful CHC treatment.

Effect of Statin Therapy on the Carboxypeptidase U (CPU, TAFIa, CPB2) System in Patients With Hyperlipidemia: A Proof-of-concept Observational Study.

PURPOSE: Statins are commonly used in patients with hypercholesterolemia to lower their cholesterol levels and to reduce their cardiovascular risk. There is also considerable evidence that statins possess a range of cholesterol-independent effects, including profibrinolytic properties. This pilot study aimed to explore the influence of statins on procarboxypeptidase U (proCPU) biology and to search for possible effects and associations that can be followed up in a larger study. METHODS: Blood was collected from 16 patients with hyperlipidemia, before and after 3 months of statin therapy (simvastatin 20 mg or atorvastatin 20 mg). Fifteen age-matched normolipemic persons served as control subjects. Lipid parameters and markers of inflammation and fibrinolysis (proCPU levels and clot lysis times) were determined in all samples. FINDINGS: Mean (SD) proCPU levels were significantly higher in patients with hypercholesterolemia compared to control subjects (1186 [189] U/L vs 1061 [60] U/L). Treatment of these patients with a statin led to a significant average decrease of 11.6% in proCPU levels and brought the proCPU concentrations to the same level as in the control subjects. On a functional level, enhancement in plasma fibrinolytic potential was observed in the statin group, with the largest improvement in fibrinolysis seen in patients with the highest baseline proCPU levels and largest proCPU decrease upon statin treatment. IMPLICATIONS: Increased proCPU levels are present in patients with hyperlipidemia. Statin treatment significantly decreased proCPU levels and improved plasma fibrinolysis in these patients. Moreover, our study indicates that patients with high baseline proCPU levels are most likely to benefit from statin therapy. The latter should be examined further in a large cohort.

Carboxypeptidase U (CPU, TAFIa, CPB2) in Thromboembolic Disease: What Do We Know Three Decades after Its Discovery?

Procarboxypeptidase U (proCPU, TAFI, proCPB2) is a basic carboxypeptidase zymogen that is converted by thrombin(-thrombomodulin) or plasmin into the active carboxypeptidase U (CPU, TAFIa, CPB2), a potent attenuator of fibrinolysis. As CPU forms a molecular link between coagulation and fibrinolysis, the development of CPU inhibitors as profibrinolytic agents constitutes an attractive new concept to improve endogenous fibrinolysis or to increase the efficacy of thrombolytic therapy in thromboembolic diseases. Furthermore, extensive research has been conducted on the in vivo role of CPU in (the acute phase of) thromboembolic disease, as well as on the hypothesis that high proCPU levels and the Thr/Ile325 polymorphism may cause a thrombotic predisposition. In this paper, an overview is given of the methods available for measuring proCPU, CPU, and inactivated CPU (CPUi), together with a summary of the clinical data generated so far, ranging from the current knowledge on proCPU concentrations and polymorphisms as potential thromboembolic risk factors to the positioning of different CPU forms (proCPU, CPU, and CPUi) as diagnostic markers for thromboembolic disease, and the potential benefit of pharmacological inhibition of the CPU pathway.

Selective inhibition of carboxypeptidase U may reduce microvascular thrombosis in rat experimental stroke.

BACKGROUND: Carboxypeptidase U (CPU, CPB2, TAFIa) is a potent attenuator of fibrinolysis. The inhibition of CPU is thus an interesting strategy for improving thrombolysis. OBJECTIVES: The time course of CPU generation and proCPU consumption were assessed in an experimental rat model of acute ischemic stroke (AIS). In addition, the effects of the selective CPU inhibitor AZD9684 on CPU kinetics, microvascular thrombosis (MT), and AIS outcome were evaluated. METHODS: Rats were subjected to transient middle cerebral artery occlusion (tMCAO) and received recombinant tissue-type plasminogen activator (tPA), a specific CPU inhibitor (AZD9684), combination therapy of tPA and AZD9684, or saline for 1 hour using a randomized treatment regime. CPU and proCPU levels were determined at five time points and assessed in light of outcome parameters (a.o.: infarct volume and fibrin[ogen] deposition as a measure for MT). RESULTS: Clear activation of the CPU system was observed after AIS induction, in both saline- and tPA-treated rats. Maximal CPU activities were observed at treatment cessation and were higher in tPA-treated animals compared to the saline group. Concomitant proCPU consumption was more pronounced in tPA-treated rats. AZD9684 suppressed the CPU activity and reduced fibrin(ogen) deposition, suggesting a reduction of MT. Nonetheless, a significant decrease in infarct volume was not observed. CONCLUSIONS: A pronounced activation of the CPU system was observed during tMCAO in rats. Selective inhibition of CPU with AZD9684 was able to reduce fibrin(ogen) deposition and brain edema, suggesting a reduction of MT but without a significant effect on final infarct volume.

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.

A new pedigree with thrombomodulin-associated coagulopathy in which delayed fibrinolysis is partially attenuated by co-inherited TAFI deficiency.

BACKGROUND: Thrombomodulin-associated coagulopathy (TM-AC) is a rare bleeding disorder in which a single reported p.Cys537* variant in the thrombomodulin gene THBD causes high plasma thrombomodulin (TM) levels. High TM levels attenuate thrombin generation and delay fibrinolysis. OBJECTIVES: To report the characteristics of pedigree with a novel THBD variant causing TM-AC, and co-inherited deficiency of thrombin-activatable fibrinolysis inhibitor (TAFI). PATIENTS/METHODS: Identification of pathogenic variants in hemostasis genes by next-generation sequencing and case recall for deep phenotyping. RESULTS: Pedigree members with a previously reported THBD variant predicting p.Pro496Argfs*10 and chain truncation in TM transmembrane domain had abnormal bleeding and greatly increased plasma TM levels. Affected cases had attenuated thrombin generation and delayed fibrinolysis similar to previous reported TM_AC cases with THBD p.Cys537*. Coincidentally, some pedigree members also harbored a stop-gain variant in CPB2 encoding TAFI. This reduced plasma TAFI levels but was asymptomatic. Pedigree members with TM-AC caused by the p.Pro496Argfs*10 THBD variant and also TAFI deficiency had a partially attenuated delay in fibrinolysis, but no change in the defective thrombin generation. CONCLUSIONS: These data extend the reported genetic repertoire of TM-AC and establish a common molecular pathogenesis arising from high plasma levels of TM extra-cellular domain. The data further confirm that the delay in fibrinolysis associated with TM-AC is directly linked to increased TAFI activation. The combination of the rare variants in the pedigree members provides a unique genetic model to develop understanding of the thrombin-TM system and its regulation of TAFI.

Inhibition of the procarboxypeptidase U (proCPU, TAFI, proCPB2) system due to hemolysis.

Essentials Hemolytic influence on the (pro)carboxypeptidase U ((pro)CPU) system is not known. In the current manuscript, this was assessed by spiking pooled normal plasma with hemolysate. CPU activity, proCPU levels, and clot lysis times showed a dose-dependent hemolytic bias. The observed bias in the several CPU related parameters is due to inhibition of CPU activity. INTRODUCTION: Spurious hemolysis of samples is the leading cause of interference in coagulation testing and was described to interfere in fibrinolysis assays. The influence of hemolysis on the procarboxypeptidase U (proCPU) system is not known. METHODS: By means of spiking of hemolysate in pooled normal plasma, the effect of hemolysis on CPU, proCPU, and functional clot lysis assays was assessed. The influence of hemolysis on CPU generation during in vitro clot lysis was also evaluated. Cutoffs corresponding to maximal acceptable bias were determined. RESULTS AND DISCUSSION: When active CPU was added to pooled plasma, a severe decrease in activity - up to 97.2% inhibition - was seen with increasing plasma concentrations of oxyhemoglobin (oxyHb) and the 10% cutoff value was found to be 0.3 g/L oxyHb. Using an activity-based assay, proCPU levels appeared to decrease gradually with increased hemolysis (maximal reduction of 19.5%) with a 10% cutoff value of 4.2 g/L oxyHb. The relative clot lysis time (CLT) showed a maximal negative bias of 68.5%. The reduction in CLT paralleled a significant reduction of the first CPU activity peak during clot lysis. The cutoff value for the CLT was 0.4 g/L oxyHb. In presence of thrombomodulin (TM), CLT+TM was not affected up to 8.0 g/L oxyHb. CONCLUSION: These data indicate a clear inhibition of the CPU system because of hemolysis resulting in an increase of lysis in functional fibrinolysis assays. We were able to quantify the inhibitory effect and to propose cutoff values for every parameter.

The EBI2-oxysterol axis promotes the development of intestinal lymphoid structures and colitis.

The gene encoding for Epstein-Barr virus-induced G-protein-coupled receptor 2 (EBI2) is a risk gene for inflammatory bowel disease (IBD). Together with its oxysterol ligand 7α,25-dihydroxycholesterol, EBI2 mediates migration and differentiation of immune cells. However, the role of EBI2 in the colonic immune system remains insufficiently studied. We found increased mRNA expression of EBI2 and oxysterol-synthesizing enzymes (CH25H, CYP7B1) in the inflamed colon of patients with ulcerative colitis and mice with acute or chronic dextran sulfate sodium (DSS) colitis. Accordingly, we detected elevated levels of 25-hydroxylated oxysterols, including 7α,25-dihydroxycholesterol in mice with acute colonic inflammation. Knockout of EBI2 or CH25H did not affect severity of DSS colitis; however, inflammation was decreased in male EBI2-/- mice in the IL-10 colitis model. The colonic immune system comprises mucosal lymphoid structures, which accumulate upon chronic inflammation in IL-10-deficient mice and in chronic DSS colitis. However, EBI2-/- mice formed significantly less colonic lymphoid structures at baseline and showed defects in inflammation-induced accumulation of lymphoid structures. In summary, we report induction of the EBI2-7α,25-dihydroxycholesterol axis in colitis and a role of EBI2 for the accumulation of lymphoid tissue during homeostasis and inflammation. These data implicate the EBI2-7α,25-dihydroxycholesterol axis in IBD pathogenesis.

Liver Allograft Failure After Nivolumab Treatment-A Case Report With Systematic Literature Research.

BACKGROUND: Orthotopic liver transplantation (OLT) is a potential curative treatment in patients with hepatocellular carcinoma (HCC); however, treatment options for recurrent HCC after OLT are limited. Immune checkpoint inhibitors, such as nivolumab, an inhibitor of programmed cell death protein 1, have been successfully used for metastatic HCC but data on safety of nivolumab following solid organ transplantation are limited. METHODS: We report a 53-year-old woman with HCC who was treated with OLT. After 2 years, HCC recurred. Initial treatment with sorafenib was discontinued due to side effects and disease progression. Progressive HCC in the lung and lymph nodes was subsequently treated with nivolumab. One week after the first nivolumab dose, rapid progressive liver dysfunction was noted. Liver biopsy revealed severe cellular graft rejection prompting treatment with intravenous steroids and tacrolimus. Liver function continued to decline, leading to severe coagulopathy. The patient succumbed to intracranial hemorrhage. RESULTS: A systematic PubMed search revealed 29 cases treated with a checkpoint inhibitor following solid organ transplantation. Loss of graft was described in 4 (36%) of 11 cases with OLT and in 7 (54%) of 13 cases after kidney transplantation. However, cases with favorable outcome were also described. Eighteen cases with adverse events were identified upon searching the World Health Organization database VigiBase, including 2 cases with fatal outcome in liver transplant recipients due to graft loss. CONCLUSION: Experience with checkpoint inhibitors in solid organ transplant recipients is limited. Published cases so far suggest severe risks for graft loss as high as 36% to 54%.

Targeting senescent cholangiocytes and activated fibroblasts with B-cell lymphoma-extra large inhibitors ameliorates fibrosis in multidrug resistance 2 gene knockout (Mdr2-/- ) mice.

Cholangiocyte senescence has been linked to primary sclerosing cholangitis (PSC). Persistent secretion of growth factors by senescent cholangiocytes leads to the activation of stromal fibroblasts (ASFs), which are drivers of fibrosis. The activated phenotype of ASFs is characterized by an increased sensitivity to apoptotic stimuli. Here, we examined the mechanisms of apoptotic priming in ASFs and explored a combined targeting strategy to deplete senescent cholangiocytes and ASFs from fibrotic tissue to ameliorate liver fibrosis. Using a coculture system, we determined that senescent cholangiocytes promoted quiescent mesenchymal cell activation in a platelet-derived growth factor (PDGF)-dependent manner. We also identified B-cell lymphoma-extra large (Bcl-xL) as a key survival factor in PDGF-activated human and mouse fibroblasts. Bcl-xL was also up-regulated in senescent cholangiocytes. In vitro, inhibition of Bcl-xL by the small molecule Bcl-2 homology domain 3 mimetic, A-1331852, or Bcl-xL-specific small interfering RNA induced apoptosis in PDGF-activated fibroblasts, but not in quiescent fibroblasts. Likewise, inhibition of Bcl-xL reduced the survival and increased apoptosis of senescent cholangiocytes, compared to nonsenescent cells. Treatment of multidrug resistance 2 gene knockout (Mdr2-/- ) mice with A-1331852 resulted in an 80% decrease in senescent cholangiocytes, a reduction of fibrosis-inducing growth factors and cytokines, decrease of α-smooth muscle actin-positive ASFs, and finally in a significant reduction of liver fibrosis. CONCLUSION: Bcl-xL is a key survival factor in ASFs as well as in senescent cholangiocytes. Treatment with the Bcl-xL-specific inhibitor, A-1331852, reduces liver fibrosis, possibly by a dual effect on activated fibroblasts and senescent cholangiocytes. This mechanism represents an attractive therapeutic strategy in biliary fibrosis. (Hepatology 2018;67:247-259).

Targeting cholangiocarcinoma.

Cholangiocarcinoma (CCA) represents a diverse group of epithelial cancers associated with the biliary tract, and can best be stratified anatomically into intrahepatic (iCCA), perihilar (pCCA) and distal (dCCA) subsets. Molecular profiling has identified genetic aberrations associated with these anatomic subsets. For example, IDH catalytic site mutations and constitutively active FGFR2 fusion genes are predominantly identified in iCCA, whereas KRAS mutations and PRKACB fusions genes are identified in pCCA and dCCA. Clinical trials targeting these specific driver mutations are in progress. However, The Tumor Genome Atlas (TCGA) marker analysis of CCA also highlights the tremendous molecular heterogeneity of this cancer rendering comprehensive employment of targeted therapies challenging. CCA also display a rich tumor microenvironment which may be easier to target. For example, targeting cancer associated fibroblasts for apoptosis with BH3-mimetics and/or and reversing T-cell exhaustion with immune check point inhibitors may help aid in the treatment of this otherwise devastating malignancy. Combinatorial therapy attacking the tumor microenvironment plus targeted therapy may help advance treatment for CCA. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.

Stent-over-sponge (SOS): a novel technique complementing endosponge therapy for foregut leaks and perforations.

BACKGROUND AND STUDY AIMS: Endoluminal vacuum therapy (EVT) has evolved as a promising option for endoscopic treatment of foregut wall injuries in addition to the classic closure techniques using clips or stents. To improve vacuum force and maintain esophageal passage, we combined endosponge treatment with a partially covered self-expandable metal stent (stent-over-sponge; SOS). PATIENTS AND METHODS: Twelve patients with infected upper gastrointestinal wall defects were treated with the SOS technique. RESULTS: Indications for SOS were anastomotic leakage after surgery (n = 11) and chronic foregut fistula (n = 1). SOS treatment was used as a first-line treatment in seven patients with a success rate of 71.4 % (5/7) and as a second-line treatment after failed previous EVT treatment in five patients (success rate 80 %; 4/5). Overall, SOS treatment was successful in 75 % of patients (9/12). No severe adverse events occurred. CONCLUSION : SOS is an effective method to treat severely infected foregut wall defects in patients where EVT has failed, and also as a first-line treatment. Comparative prospective studies are needed to confirm our preliminary results.

A Dual Role of Caspase-8 in Triggering and Sensing Proliferation-Associated DNA Damage, a Key Determinant of Liver Cancer Development.

Concomitant hepatocyte apoptosis and regeneration is a hallmark of chronic liver diseases (CLDs) predisposing to hepatocellular carcinoma (HCC). Here, we mechanistically link caspase-8-dependent apoptosis to HCC development via proliferation- and replication-associated DNA damage. Proliferation-associated replication stress, DNA damage, and genetic instability are detectable in CLDs before any neoplastic changes occur. Accumulated levels of hepatocyte apoptosis determine and predict subsequent hepatocarcinogenesis. Proliferation-associated DNA damage is sensed by a complex comprising caspase-8, FADD, c-FLIP, and a kinase-dependent function of RIPK1. This platform requires a non-apoptotic function of caspase-8, but no caspase-3 or caspase-8 cleavage. It may represent a DNA damage-sensing mechanism in hepatocytes that can act via JNK and subsequent phosphorylation of the histone variant H2AX.

Nonampullary Duodenal Adenomas Rarely Recur after Complete Endoscopic Resection: A Swiss Experience Including a Literature Review.

INTRODUCTION: Duodenal polyps and especially duodenal adenomas are a rare and mostly coincidental finding in patients undergoing upper gastrointestinal endoscopy. Due to their malignant potential, duodenal adenomas should be removed upon diagnosis. So far, the limited available data on the performance of endoscopic polypectomy show conflicting results with regard to adverse events and the adenoma recurrence rate. PATIENTS AND METHODS: After summarizing the currently available data, we retrospectively analyzed all patients undergoing endoscopic resection of nonampullary duodenal adenomas (NAD) at our institution between 2006 and 2016. RESULTS: A total of 78 patients underwent endoscopic polypectomy for NAD adenoma. End-of-treatment success with complete resection requiring a mean of 1.2 interventions was achieved in 91% (n = 71). Procedural hemorrhage occurred in 12.8% (n = 10), whereas delayed bleeding was noted in 9% (n = 7). Duodenal perforation was registered and successfully treated in 2 cases (2.6%). No adenoma recurrence was noted following primary complete adenoma resection after a mean follow-up time of 33 months. Acute post-polypectomy bleeding was statistically significantly associated with large polyp size (p = 0.003) and lack of endoscopic prophylaxis (p = 0.0008). Delayed post-polypectomy bleeding showed a trend in the occurrence of large polyps (p = 0.064), and was statistically significantly associated with familial cancer syndrome (p = 0.019) and advanced histopathology (p = 0.013). CONCLUSION: Our data suggest that endoscopic polypectomy of NAD is well feasible with high success rates. Procedural and delayed hemorrhage seems to be the primary issue rather than adenoma recurrence. We therefore advocate referral of patients with large NAD to experienced centers for endoscopic resection.

Bcl-2 degradation is an additional pro-apoptotic effect of polo-like kinase inhibition in cholangiocarcinoma cells.

AIM: To examine the influence on apoptotic mechanisms following inhibition of polo-like kinases as therapeutically approach for cholangiocellular cancer treatment. METHODS: As most cholangiocarcinomas are chemotherapy-resistant due to mechanisms preventing tumor cell death, we investigated the effect of Cisplatin on cholangiocellular carcinoma (CCA) cell lines KMCH-1 and Mz-Ch-1. Polo-like kinases (PLK) are important regulators of the cell cycle and their inhibition is discussed as a potential therapy while PLK inhibition can regulate apoptotic mediators. Here, cells were treated with PLK inhibitor BI6727 (Volasertib), Cisplatin, and in combination of both compounds. Cell viability was assessed by MTT; apoptosis was measured by DAPI staining and caspase-3/-7 assay. Western blot and qRT-PCR were used to measure expression levels of apoptosis-related molecules Bax and Bcl-2. RESULTS: The cell viability in the CCA cell lines KMCH-1 and Mz-Ch-1 was reduced in all treatment conditions compared to vehicle-treated cells. Co-treatment with BI6727 and cisplatin could even enhance the cytotoxic effect of cisplatin single treatment. Thus, co-treatment of cisplatin with BI6727 could slightly enhance the cytotoxic effect of the cisplatin in both cell lines whereas there was evidence of increased apoptosis induction solely in Mz-Ch-1 as compared to KMCH-1. Moreover, PLK inhibition decreases protein levels of Bcl-2; an effect that can be reversed by the proteasomal degradation inhibitor MG-132. In contrast, protein levels of Bax were not found to be altered by PLK inhibition. These findings indicate that cytotoxic effects of Cisplatin in Mz-Ch-1 cells can be enhanced by cotreatment with BI6727. CONCLUSION: In conclusion, BI6727 treatment can sensitize CCA cells to cisplatin-induced apoptosis with proteasomal Bcl-2 degradation as an additional pro-apoptotic effect.