PRMT5 Mediated HIF1α Signaling and Ras-Related Nuclear Protein as Promising Biomarker in Hepatocellular Carcinoma

Protein arginine N-methyltransferase 5 (PRMT5) has been identified as a potential therapeutic target for various cancer types. However, its role in regulating the hepatocellular carcinoma (HCC) transcriptome remains poorly understood. In this study, publicly available databases were employed to investigate PRMT5 expression, its correlation with overall survival, targeted pathways, and genes of interest in HCC. Additionally, we utilized in-house generated NGS data to explore PRMT5 expression in dysplastic nodules compared to hepatocellular carcinoma. Our findings revealed that PRMT5 is significantly overexpressed in HCC compared to normal liver, and elevated expression correlates with poor overall survival. To gain insights into the mechanism driving PRMT5 overexpression in HCC, we analyzed promoter CpG islands and methylation status in HCC compared to normal tissues. Pathway analysis of PRMT5 knockdown in the HCC cells revealed a connection between PRMT5 expression and genes related to the HIF1α pathway. Additionally, by filtering PRMT5-correlated genes within the HIF1α pathway and selecting up/downregulated genes in HCC patients, we identified Ras-related nuclear protein (RAN) as a target associated with overall survival. For the first time, we report that PRMT5 is implicated in the regulation of HIF1A and RAN genes, suggesting the potential prognostic utility of PRMT5 in HCC.

RAC1b Collaborates with TAp73α-SMAD4 Signaling to Induce Biglycan Expression and Inhibit Basal and TGF-β-Driven Cell Motility in Human Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer type characterized by a marked desmoplastic tumor stroma that is formed under the influence of transforming growth factor (TGF)-β. Data from mouse models of pancreatic cancer have revealed that transcriptionally active p73 (TAp73) impacts the TGF-β pathway through activation of Smad4 and secretion of biglycan (Bgn). However, whether this pathway also functions in human PDAC cells has not yet been studied. Here, we show that RNA interference-mediated silencing of TAp73 in PANC-1 cells strongly reduced the stimulatory effect of TGF-β1 on BGN. TAp73-mediated regulation of BGN, and inhibition of TGF-β signaling through a (Smad-independent) ERK pathway, are reminiscent of what we previously observed for the small GTPase, RAC1b, prompting us to hypothesize that in human PDAC cells TAp73 and RAC1b are part of the same tumor-suppressive pathway. Like TAp73, RAC1b induced SMAD4 protein and mRNA expression. Moreover, siRNA-mediated knockdown of RAC1b reduced TAp73 mRNA levels, while ectopic expression of RAC1b increased them. Inhibition of BGN synthesis or depletion of secreted BGN from the culture medium reproduced the promigratory effect of RAC1b or TAp73 silencing and was associated with increased basal and TGF-β1-dependent ERK activation. BGN also phenocopied the effects of RAC1b or TAp73 on the expression of downstream effectors, like the EMT markers E-cadherin, Vimentin and SNAIL, as well as on negative regulation of the ALK2-SMAD1/5 arm of TGF-β signaling. Collectively, we showed that tumor-suppressive TAp73-Smad4-Bgn signaling also operates in human cells and that RAC1b likely acts as an upstream activator of this pathway.

Obesity-related Plasma CXCL10 Drives CX3CR1-dependent Monocytic Secretion of Macrophage Migration Inhibitory Factor

Obesity is characterized by excessive body fat accumulation and comorbidities such as diabetes mellitus, cardiovascular disease, and obstructive sleep apnea syndrome (OSAS). Both obesity and OSAS are associated with immune disturbance, alterations of systemic inflammatory mediators, and immune cell recruitment to metabolic tissues. Chemokine CXCL10 is an important regulator of proinflammatory immune responses and is significantly increased in patients with severe obesity. This research project aims to investigate the impact of CXCL10 on human monocytes in patients with obesity. We studied the distribution of the CD14/CD16 monocyte subsets as well as their CX3CR1 expression patterns in whole-blood measurements from 92 patients with obesity and/or OSAS with regard to plasma CXCL10 values and individual clinical parameters. Furthermore, cytokine secretion by THP-1 monocytes in response to CXCL10 was analyzed. Data revealed significantly elevated plasma CXCL10 in patients with obesity with an additive effect of OSAS. CXCL10 was found to drive monocytic secretion of macrophage migration inhibitory factor via receptor protein CX3CR1, which significantly correlated with the individual body mass index. Our data show, for the first time, to our knowledge, that CX3CR1 is involved in alternative CXCL10 signaling in human monocytes in obesity-related inflammation. Obesity is a multifactorial disease, and further investigations regarding the complex interplay between obesity-related inflammatory mediators and systemic immune balances will help to better understand and improve the individual situation of our patients.

TAp73 Inhibits EMT and Cell Migration in Pancreatic Cancer Cells through Promoting SMAD4 Expression and SMAD4-Dependent Inhibition of ERK Activation

Pancreatic ductal adenocarcinoma (PDAC) is a fatal disease due to early metastatic spread, late diagnosis and the lack of efficient therapies. A major driver of cancer progression and hurdle to successful treatment is transforming growth factor (TGF)-β. Recent data from pancreatic cancer mouse models showed that transcriptionally active p73 (TAp73), a p53 family member, inhibits tumor progression through promoting tumor suppressive canonical TGF-β/Smad signaling, while preventing non-canonical TGF-β signaling through extracellular signal-regulated kinases (ERK)1/2. Here, we studied whether this mechanism also operates in human PDAC. Using the PDAC-derived tumor cell lines PANC-1, HPAFII and L3.6pl, we showed that TAp73 induces the expression of the epithelial marker and invasion suppressor E-cadherin and the common-mediator Smad, SMAD4, while at the same time suppressing expression of the EMT master regulator SNAIL and basal and TGF-β1-induced activation of ERK1 and ERK2. Using dominant-negative and RNA interference-based inhibition of SMAD4 function, we went on to show that inhibition of ERK activation by TAp73 is mediated through SMAD4. Intriguingly, both SMAD4 and the α isoform of TAp73-but not the β isoform-interfered with cell migration, as shown by xCELLigence technology. Our findings highlighted the role of TAp73-SMAD4 signaling in tumor suppression of human PDAC and identified direct inhibition of basal and TGF-β-stimulated pro-invasive ERK activation as an underlying mechanism.

Plasma Leptin Levels, Obstructive Sleep Apnea Syndrome, and Diabetes Are Associated with Obesity-Related Alterations of Peripheral Blood Monocyte Subsets

Obesity is a dramatically increasing disease, accompanied with comorbidities such as cardiovascular disease and obstructive sleep apnea syndrome (OSAS). Both obesity and OSAS per se are associated with systemic inflammation. However, the multifactorial impact of obesity, OSAS, and its concomitant diseases on the immunological characteristics of circulating monocytes has not yet been fully resolved. Monocyte subsets of 82 patients with obesity were analyzed in whole blood measurements in terms of the CD14/CD16 cell surface expression patterns and different monocytic adhesion molecules using flow cytometry. Plasma levels of adipokines adiponectin and leptin of all patients were evaluated and correlated with accompanying cellular and clinical values. Whole blood measurements revealed a significant overall redistribution of CD14/CD16 monocyte subsets in patients with obesity. Monocytic adhesion molecules CD11a, CD11b, and CX3CR1 were significantly elevated. The observed alterations significantly correlated with plasma leptin levels and diabetes status as crucial amplifying factors. The additive impact of obesity, diabetes, and OSAS on the immunological balance of peripheral blood monocytes requires a coordinated regimen in terms of therapeutic treatment, respiratory support, and weight loss to improve the systemic immunity in these patients.

Differential Effects of Somatostatin, Octreotide, and Lanreotide on Neuroendocrine Differentiation and Proliferation in Established and Primary NET Cell Lines: Possible Crosstalk with TGF-β Signaling

GEP-NETs are heterogeneous tumors originating from the pancreas (panNET) or the intestinal tract. Only a few patients with NETs are amenable to curative tumor resection, and for most patients, only palliative treatments to successfully control the disease or manage symptoms remain, such as with synthetic somatostatin (SST) analogs (SSAs), such as octreotide (OCT) or lanreotide (LAN). However, even cells expressing low levels of SST receptors (SSTRs) may exhibit significant responses to OCT, which suggests the possibility that SSAs signal through alternative mechanisms, e.g., transforming growth factor (TGF)-β. This signaling mode has been demonstrated in the established panNET line BON but not yet in other permanent (i.e., QGP) or primary (i.e., NT-3) panNET-derived cells. Here, we performed qPCR, immunoblot analyses, and cell counting assays to assess the effects of SST, OCT, LAN, and TGF-β1 on neuroendocrine marker expression and cell proliferation in NT-3, QGP, and BON cells. SST and SSAs were found to regulate a set of neuroendocrine genes in all three cell lines, with the effects of SST, mainly LAN, often differing from those of OCT. However, unlike NT-3 cells, BON cells failed to respond to OCT with growth arrest but paradoxically exhibited a growth-stimulatory effect after treatment with LAN. As previously shown for BON, NT-3 cells responded to TGF-β1 treatment with induction of expression of SST and SSTR2/5. Of note, the ability of NT-3 cells to respond to TGF-β1 with upregulation of the established TGF-β target gene SERPINE1 depended on cellular adherence to a collagen-coated matrix. Moreover, when applied to NT-3 cells for an extended period, i.e., 14 days, TGF-β1 induced growth suppression as shown earlier for BON cells. Finally, next-generation sequencing-based identification of microRNAs (miRNAs) in BON and NT-3 revealed that SST and OCT impact positively or negatively on the regulation of specific miRNAs. Our results suggest that primary panNET cells, such as NT-3, respond similarly as BON cells to SST, SSA, and TGF-β treatment and thus provide circumstantial evidence that crosstalk of SST and TGF-β signaling is not confined to BON cells but is a general feature of panNETs.

Suppressive Role of ACVR1/ALK2 in Basal and TGFβ1-Induced Cell Migration in Pancreatic Ductal Adenocarcinoma Cells and Identification of a Self-Perpetuating Autoregulatory Loop Involving the Small GTPase RAC1b

Pancreatic ductal adenocarcinoma (PDAC) cells are known for their high invasive/metastatic potential, which is regulated in part by the transforming growth factor β1 (TGFβ1). The involvement of at least two type I receptors, ALK5 and ALK2, that transmit downstream signals of the TGFβ via different Smad proteins, SMAD2/3 and SMAD1/5, respectively, poses the issue of their relative contribution in regulating cell motility. Real-time cell migration assays revealed that the selective inhibition of ALK2 by RNAi or dominant-negative interference with a kinase-dead mutant (ALK2-K233R) strongly enhanced the cells’ migratory activity in the absence or presence of TGFβ1 stimulation. Ectopic ALK2-K233R expression was associated with an increase in the protein levels of RAC1 and its alternatively spliced isoform, RAC1b, both of which are implicated in driving cell migration and invasion. Conversely, the RNAi-mediated knockdown or CRISPR/Cas9-mediated knockout of RAC1b resulted in the upregulation of the expression of ALK2, but not that of the related BMP type I receptors, ALK3 or ALK6, and elevated the phosphorylation of SMAD1/5. PDAC is a heterogeneous disease encompassing tumors with different histomorphological subtypes, ranging from epithelial/classical to extremely mesenchymal. Upon treatment of various established and primary PDAC cell lines representing these subtypes with the ALK2 inhibitor, LDN-193189, well-differentiated, epithelial cell lines responded with a much stronger increase in the basal and TGFβ1-dependent migratory activity than poorly differentiated, mesenchymal ones. These data show that (i) ALK2 inhibits migration by suppressing RAC1/RAC1b proteins, (ii) ALK2 and RAC1b act together in a self-perpetuating the autoregulatory negative feedback loop to mutually control their expression, and (iii) the ALK2 antimigratory function appears to be particularly crucial in protecting epithelial subtype cells from becoming invasive, both spontaneously and in a TGFβ-rich tumor microenvironment.

The Quasimesenchymal Pancreatic Ductal Epithelial Cell Line PANC-1-A Useful Model to Study Clonal Heterogeneity and EMT Subtype Shifting

Simple Summary

Malignant tumors often escape therapy due to clonal propagation of a subfraction of drug-resistant cancer cells. The underlying phenomenon of intratumoral heterogeneity is driven by epithelial–mesenchymal plasticity (EMP) involving the developmental programs, epithelial–mesenchymal transition (EMT), in which epithelial cells are converted to invasive mesenchymal cells, and the reverse process, mesenchymal–epithelial transition (MET), which allows for metastatic outgrowth at distant sites. For therapeutic targeting of EMP, a better understanding of this process is required; however, cellular models with which to study EMP in pancreatic ductal adenocarcinoma (PDAC) are scarce. Using single-cell clonal analysis, we have found the PDAC cell line, PANC-1, to consist of cells with different E/M phenotypes and functional attributes. Parental PANC-1 cultures could be induced in vitro to shift towards either a more mesenchymal or a more epithelial phenotype, and this bidirectional shift was controlled by the small GTPases RAC1 and RAC1b, together identifying PANC-1 cells as a useful model with which to study EMP.

Abstract

Intratumoral heterogeneity (ITH) is an intrinsic feature of malignant tumors that eventually allows a subfraction of resistant cancer cells to clonally evolve and cause therapy failure or relapse. ITH, cellular plasticity and tumor progression are driven by epithelial–mesenchymal transition (EMT) and the reverse process, MET. During these developmental programs, epithelial (E) cells are successively converted to invasive mesenchymal (M) cells, or back to E cells, by passing through a series of intermediate E/M states, a phenomenon termed E–M plasticity (EMP). The induction of MET has clinical potential as it can block the initial EMT stages that favor tumor cell dissemination, while its inhibition can curb metastatic outgrowth at distant sites. In pancreatic ductal adenocarcinoma (PDAC), cellular models with which to study EMP or MET induction are scarce. Here, we have generated single cell-derived clonal cultures of the quasimesenchymal PDAC-derived cell line, PANC-1, and found that these differ strongly with respect to cell morphology and EMT marker expression, allowing for their tentative classification as E, E/M or M. Interestingly, the different EMT phenotypes were found to segregate with differences in tumorigenic potential in vitro, as measured by colony forming and invasive activities, and in circadian clock function. Moreover, the individual clones the phenotypes of which remained stable upon prolonged culture also responded differently to treatment with transforming growth factor (TGF)β1 in regard to regulation of growth and individual TGFβ target genes, and to culture conditions that favour ductal-to-endocrine transdifferentiation as a more direct measure for cellular plasticity. Of note, stimulation with TGFβ1 induced a shift in parental PANC-1 cultures towards a more extreme M and invasive phenotype, while exposing the cells to a combination of the proinflammatory cytokines IFNγ, IL1β and TNFα (IIT) elicited a shift towards a more E and less invasive phenotype resembling a MET-like process. Finally, we show that the actions of TGFβ1 and IIT both converge on regulating the ratio of the small GTPase RAC1 and its splice isoform, RAC1b. Our data provide strong evidence for dynamic EMT–MET transitions and qualify this cell line as a useful model with which to study EMP.

Activation of a Ductal-to-Endocrine Transdifferentiation Transcriptional Program in the Pancreatic Cancer Cell Line PANC-1 Is Controlled by RAC1 and RAC1b through Antagonistic Regulation of Stemness Factors

Simple Summary

For patients with metastatic pancreatic ductal adenocarcinoma (PDAC) there is currently no cure; hence, novel effective therapies are desperately needed. Among PDAC patients, the tumor cell phenotypes are heterogeneous as a result of epithelial–mesenchymal transition, a process that endows them with the ability to metastasize, resist therapy, and generate cancer stem cells. The heightened plasticity of quasimesenchymal and potentially metastatic tumor cells may, however, also be exploited for their transdifferentiation into benign, highly differentiated or post-mitotic cells. Since PDAC patients often have a need for replacement of insulin-producing cells, conversion of tumor cells with a ductal/exocrine origin to endocrine β cell-like cells is an attractive therapeutic option. Successful transdifferentiation into insulin-producing cells has been reported for the quasimesenchymal cell line PANC-1; however, the mechanistic basis of this transformation process is unknown. Here, we show that the small GTPases, RAC1 and RAC1b control this process by antagonistic regulation of stemness genes.

Abstract

Epithelial–mesenchymal transition (EMT) is a driving force for tumor growth, metastatic spread, therapy resistance, and the generation of cancer stem cells (CSCs). However, the regained stem cell character may also be exploited for therapeutic conversion of aggressive tumor cells to benign, highly differentiated cells. The PDAC-derived quasimesenchymal-type cell lines PANC-1 and MIA PaCa-2 have been successfully transdifferentiated to endocrine precursors or insulin-producing cells; however, the underlying mechanism of this increased plasticity remains elusive. Given its crucial role in normal pancreatic endocrine development and tumor progression, both of which involve EMT, we analyzed here the role of the small GTPase RAC1. Ectopic expression in PANC-1 cells of dominant negative or constitutively active mutants of RAC1 activation blocked or enhanced, respectively, the cytokine-induced activation of a ductal-to-endocrine transdifferentiation transcriptional program (deTDtP) as revealed by induction of the NEUROG3, INS, SLC2A2, and MAFA genes. Conversely, ectopic expression of RAC1b, a RAC1 splice isoform and functional antagonist of RAC1-driven EMT, decreased the deTDtP, while genetic knockout of RAC1b dramatically increased it. We further show that inhibition of RAC1 activation attenuated pluripotency marker expression and self-renewal ability, while depletion of RAC1b dramatically enhanced stemness features and clonogenic potential. Finally, rescue experiments involving pharmacological or RNA interference-mediated inhibition of RAC1 or RAC1b, respectively, confirmed that both RAC1 isoforms control the deTDtP in an opposite manner. We conclude that RAC1 and RAC1b antagonistically control growth factor-induced activation of an endocrine transcriptional program and the generation of CSCs in quasimesenchymal PDAC cells. Our results have clinical implications for PDAC patients, who in addition to eradication of tumor cells have a need for replacement of insulin-producing cells.

The Small GTPase RAC1B: A Potent Negative Regulator of-and Useful Tool to Study-TGFβ Signaling

RAC1 and its alternatively spliced isoform, RAC1B, are members of the Rho family of GTPases. Both isoforms are involved in the regulation of actin cytoskeleton remodeling, cell motility, cell proliferation, and epithelial-mesenchymal transition (EMT). Compared to RAC1, RAC1B exhibits a number of distinctive features with respect to tissue distribution, downstream signaling and a role in disease conditions like inflammation and cancer. The subcellular locations and interaction partners of RAC1 and RAC1B vary depending on their activation state, which makes RAC1 and RAC1B ideal candidates to establish cross-talk with cancer-associated signaling pathways-for instance, interactions with signaling by transforming growth factor β (TGFβ), a known tumor promoter. Although RAC1 has been found to promote TGFβ-driven tumor progression, recent observations in pancreatic carcinoma cells surprisingly revealed that RAC1B confers anti-oncogenic properties, i.e., through inhibiting TGFβ-induced EMT. Since then, an unexpected array of mechanisms through which RAC1B cross-talks with TGFβ signaling has been demonstrated. However, rather than being uniformly inhibitory, RAC1B interacts with TGFβ signaling in a way that results in the selective blockade of tumor-promoting pathways, while concomitantly allowing tumor-suppressive pathways to proceed. In this review article, we are going to discuss the specific interactions between RAC1B and TGFβ signaling, which occur at multiple levels and include various components such as ligands, receptors, cytosolic mediators, transcription factors, and extracellular inhibitors of TGFβ ligands.

Impact of acute-on-chronic liver failure and decompensated liver cirrhosis on psychosocial burden and quality of life of patients and their close relatives

Background

Patients with liver cirrhosis often suffer from complications such as ascites, gastrointestinal bleeding, and infections, resulting in impaired quality of life. Frequently, the close relatives of patients also suffer from a lower quality of life in chronic diseases. In recent years, acute-to-chronic liver failure has been defined as a separate entity with high mortality. Often several organs are affected which makes intensive care therapy necessary. Little is known about the influence of acute-on-chronic-liver failure (ACLF) on the quality of life of patients and the psychosocial burden on close relatives.

Aim

The purpose of this prospective study is to investigate the influence of decompensated liver cirrhosis and the onset of ACLF of the patient’s’ quality of life and the psychosocial burden of close relatives.

Method

In this non – randomized prospective cohort study a total of 63 patients with acute decompensation of liver cirrhosis and hospital admission were enrolled in the study. To assess the quality of life of patients, the disease specific CLDQ questionnaire was assessed. In addition. Quality of life and psychosocial burden of first degree relatives was measured using the generic SF-36 questionnaire as well as the Zarit Burden Score.

Results

21 of the 63 patients suffered from ACLF. Patients with ACLF showed a lower quality of life in terms of worries compared to patients with only decompensated liver cirrhosis (3,57 ± 1,17 vs. 4,48 ± 1,27; p value: 0,008) and increased systemic symptoms (3,29 ± 1,19 vs. 4,48 ± 1,58; p value: 0,004). The univariate analysis confirmed the link between the existence of an ACLF and the concerns of patients. (p value: 0,001). The organ failure score was significantly associated with overall CLDQ scores, especially with worries and systemic symptoms of patients. Interestingly the psychosocial burden and quality of life of close relative correlates with patient’s quality of life and was influenced by the onset of an acute-on-chronic liver failure.

Conclusion

Patients with decompensated liver cirrhosis suffer from impaired quality of life. In particular, patients with ACLF have a significantly reduced quality of life. The extent of the psychosocial burden on close relative correlates with poor quality of life in patients with decompensated liver disease and is influenced by the existence of ACLF.

The mitochondrial type IB topoisomerase drives mitochondrial translation and carcinogenesis

Mitochondrial topoisomerase IB (TOP1MT) is a nuclear-encoded topoisomerase, exclusively localized to mitochondria, which resolves topological stress generated during mtDNA replication and transcription. Here, we report that TOP1MT is overexpressed in cancer tissues and demonstrate that TOP1MT deficiency attenuates tumor growth in human and mouse models of colon and liver cancer. Due to their mitochondrial dysfunction, TOP1MT-KO cells become addicted to glycolysis, which limits synthetic building blocks and energy supply required for the proliferation of cancer cells in a nutrient-deprived tumor microenvironment. Mechanistically, we show that TOP1MT associates with mitoribosomal subunits, ensuring optimal mitochondrial translation and assembly of oxidative phosphorylation complexes that are critical for sustaining tumor growth. The TOP1MT genomic signature profile, based on Top1mt-KO liver cancers, is correlated with enhanced survival of hepatocellular carcinoma patients. Our results highlight the importance of TOP1MT for tumor development, providing a potential rationale to develop TOP1MT-targeted drugs as anticancer therapies.

Prospective evaluation of the impact of covert hepatic encephalopathy on quality of life and sleep in cirrhotic patients

BACKGROUND

Minimal hepatic encephalopathy (HE) and HE grade 1 (HE1) according to the West Haven criteria have recently been grouped as one entity named-covert HE- (CHE). Data regarding the impact of CHE on health-related quality of life (HRQoL) and sleep quality are controversial.

AIM

First, to determine whether CHE affects HRQoL and sleep quality of cirrhotic patients and second, whether minimal HE (MHE) and HE1 affect HRQoL and sleep quality to a comparable extent.

METHODS

A total of 145 consecutive cirrhotic patients were enrolled. HE1 was diagnosed clinically according to the West Haven criteria. Critical flicker frequency and the Psychometric Hepatic Encephalopathy Score were used to detect MHE. Chronic Liver Disease Questionnaire (CLDQ) was used to assess HRQoL and Pittsburgh Sleep Quality Index (PSQI) was applied to assess sleep quality.

RESULTS

Covert HE was detected in 59 (40.7%) patients (MHE: n = 40; HE1: n = 19). Multivariate analysis identified CHE (P < 0.001) and female gender (P = 0.006) as independent predictors of reduced HRQoL (CLDQ total score). CHE (P = 0.021), low haemoglobin (P = 0.024) and female gender (P = 0.003) were identified as independent predictors of poor sleep quality (PSQI total score). Results of CLDQ and PSQI were comparable in patients with HE1 and MHE (CLDQ: 4.6 ± 0.9 vs 4.5 ± 1.2, P = 0.907; PSQI: 11.3 ± 3.8 vs 9.9 ± 5.0, P = 0.3).

CONCLUSION

Covert HE was associated with impaired HRQoL and sleep quality. MHE and HE1 affected both outcomes to a comparable extent supporting the use of CHE as a clinically useful term for patients with both entities of HE in clinical practice.

High-definition endoscopy with iScan and Lugol's solution for the detection of inflammation in patients with nonerosive reflux disease: histologic evaluation in comparison with a control group

Nonerosive reflux disease (NERD) is commonly diagnosed in patients with symptoms of reflux. The aim of the present study was to determine whether high-definition endoscopy (HD) plus equipped with the iScan function or chromoendoscopy with Lugol's solution might permit the differentiation of NERD patients from those without reflux symptoms, proven by targeted biopsies of endoscopic lesions. A total of 100 patients without regular intake of proton pump inhibitors and with a normal conventional upper endoscopy were prospectively divided into NERD patients and controls. A second upper endoscopy was performed using HD+ with additional iScan function and then Lugol's solution was applied. Biopsy specimens were taken from the gastroesophageal junction in all patients. A total of 65 patients with reflux symptoms and 27 controls were included. HD(+) endoscopy with iScan revealed subtle mucosal breaks in 52 patients; the subsequent biopsies confirmed esophagitis in all cases. After Lugol's solution, 58 patients showed mucosal breaks. Sensitivity for the iScan procedure was 82.5%, whereas that for Lugol's solution was 92.06%. Excellent positive predictive values of 100% and 98.3%, respectively, were noted. The present study suggests that the majority of patients with NERD and typical symptoms of reflux disease can be identified by iScan or Lugol's chromoendoscopy as minimal erosive reflux disease (ERD) patients.

[Etiology and complications of liver cirrhosis: data from a German centre]

BACKGROUND

Liver cirrhosis develops as a terminal complication of chronic liver disease. The clinical course is determined by the underlying etiology and the accompanying risk factors, which are influenced by the geographic and cultural background.

METHODS

A total of 236 patients (159 men, 77 women, median age 57 [22-81] years) were included for retrospective analysis between July 2012 and February 2014 using standardized questionnaires during an outpatient visit at a hepatology clinic.

RESULTS

The most common etiologies of liver cirrhosis were related to alcohol consumption (52 %), chronic hepatitis C (28 %) or hepatitis B (14 %) infection and NASH (nonalcoholic steatohepatitis, 6 %). At the time of presentation 55 % patients had compensated cirrhosis corresponding to Child-Turcotte-Pugh (CTP) stage A, while 45 % were in a decompensated stage (30 % CTP B and 15 % CTP C). Subgroups were analyzed for the incidence of complications and the emergence of infections. Most frequently esophageal varices (60 %) and ascites (49 %) were observed, followed by pleural effusion (14 %), hepatic encephalopathy (25 %) or hepatorenal syndrome (18 %). 16 % of patients exhibited infection based on clinical criteria. An infective agent was isolated in 38 % of all cases with infection and of those 50 % were gram positive bacteria. In multivariate analysis only the presence of ascites was an independent risk factor for infection.

CONCLUSION

Despite improved medical therapies for viral hepatitis, these were the most frequent causes of liver cirrhosis, closely followed by alcoholic cirrhosis. The observed complications included bacterial infection and complication related to portal hypertension.

[Upper gastrointestinal bleeding and haemorrhagic shock at the end of the holidays: pre-hospital and in-hospital management of a gastrointestinal emergency]

Upon returning from holidays, a 55-year-old patient presenting with melena and haemorrhagic shock was admitted to a University hospital after receiving first emergency medical care in a German InterCity train. In an interdisciplinary effort, haemodynamics were stabilised and the airway and respiratory function were secured. Under emergency care conditions the patient then underwent an emergency upper GI endoscopy where a spurting arterial upper gastrointestinal bleeding (Forrest 1a) was found. While the bleeding could not be controlled with endoscopic techniques, definitive haemostasis was achieved with a surgical laparotomy. While not commonly established for patients with severe GI bleeding, by spontaneous implementation of an interdisciplinary trauma room approach following established trauma algorithms the team was able to achieve stabilisation of vital functions and final control of bleeding in this highly unstable patient. Although the majority of upper gastrointestinal bleedings spontaneously cease, emergency care algorithms should be developed and implemented for patients with severe gastrointestinal bleedings in shock. Following the case vignette, we discuss a potential approach and develop an exemplary protocol for shock room management in this patient subgroup.

IgG4-related sclerosing cholangitis mimicking cholangiocarcinoma

IgG4-related disease has gained increased attention worldwide. While the initial focus was on autoimmune pancreatitis which was first described in Asian populations and turned out to be of relevance in Western populations too, the scope has recently broadened towards a notion of a multi-systemic disease with very diverse manifestations such as autoimmune pancreatitis, IgG4-related sclerosing cholangitis (IgG4-SC), retroperitoneal fibrosis and tubulointerstitial nephritis. IgG4-SC (also known as IgG4-associated cholangitis, IAC) represents a rare but clinically challenging differential diagnosis in patients with obstructive jaundice and proximal extra- or intrahepatic biliary strictures which can be mistaken for cholangiocarcinoma (CC). We present the case of a 79-year-old male patient who presented with obstructive jaundice and biliary strictures at the hepatic duct bifurcation without any evidence for autoimmune pancreatitis and without elevation of serum IgG4-concentrations who underwent hemihepatectomy for suspected CC. However, on histological examination of the resection specimen CC could not be confirmed. It was only after several episodes of obstructive jaundice had reoccurred that the diagnosis of IgG4-SC could be established by reexamination of the surgical specimen which showed extensive infiltration with IgG4-positive plasma cells. Appropriate medical treatment with steroids and azathioprine led to complete remission of the disease. Early recognition of IgG4-SC can save patients from potential harmful and unnecessary surgical interventions. Here we describe the clinical features of this rare case of IgG4-SC with extensive liver tissue infiltration with IgG4-positive cells but without elevated serum IgG4 concentration or evidence of autoimmune pancreatitis. We describe diagnostic criteria for IgG4-SC and review recent insights in pathophysiology and treatment options.

[Hepatocellular carcinoma: molecular pathogenesis and novel targets for therapy]

Hepatocellular carcinomas rank among the most common cancers worldwide. They are characterized by phenotypic heterogeneity and poor response to treatment modalities. Although considerable progress in diagnosis and management of hepatocellular carcinomas has been made over the last decade, the exact biology of liver cancer remains poorly understood, overall hindering the development of new therapeutic strategies. The development of whole-genome analyses on different molecular levels greatly advanced our understanding of hepatocarcinogenesis by simultaneously investigating thousands of molecular targets. Although implementation of the results from these analyses in routine clinical practice is still limited, these next generation technologies offer unprecedented insights into the molecular mechanisms of the development of liver cancer. Overall, great promise rests on whole genomic approaches to improve the diagnostic testing and to identify novel targets for individualized treatment modalities in liver cancer.

Molecular targeting of CSN5 in human hepatocellular carcinoma: a mechanism of therapeutic response

Development of targeted therapy for hepatocellular carcinoma (HCC) remains a major challenge. We have recently identified an elevated expression of the fifth subunit of COP9 signalosome (CSN5) in early HCC as compared to dysplastic stage. In the present study, we explored the possibility of CSN5 being a potential therapeutic target for HCC. Our results show that CSN5 knockdown by small interfering (si) RNA caused a strong induction of apoptosis and inhibition of cell cycle progression in HCC cells in vitro. The downregulation of CSN5 was sufficient to interfere with CSN function as evidenced by the accumulation of neddylated Cullin1 and changes in the protein levels of CSN controlled substrates SKP2, p53, p27 and NF-kB, albeit to a different degree depending on the HCC cell line, which could account for the CSN5 knockdown phenotype. The transcriptomic analysis of CSN5 knockdown signature showed that the anti-proliferative effect was driven by a common subset of molecular alterations including downregulation of CDK6 and ITGB1, which were functionally interconnected with key oncogenic regulators MYC and TGFβ1 involved in the control of proliferation, apoptotic cell death and HCC progression. Consistent with microarray analysis, western blotting revealed that CSN5 depletion increased phosphorylation of Smad 2/3, key mediators of TGFβ1 signaling, decreased the protein levels of ITGB1, CDK6, and cyclin D1 and caused reduced expression of anti-apoptotic Bcl-2 while elevating the levels of pro-apoptotic Bak. A chemically modified variant of CSN5 siRNA was then selected for in vivo application based on the growth inhibitory effect and minimal induction of unwanted immune response. Systemic delivery of the CSN5 3/8 variant by stable-nucleic-acid-lipid-particles (SNALP) significantly suppressed the tumor growth in Huh7-luc⁺ orthotopic xenograft model. Taken together, these results indicate that CSN5 plays a pivotal role in HCC pathogenesis and maybe an attractive molecular target for systemic HCC therapy.