Minimal hepatic encephalopathy is associated with a higher risk of overt hepatic encephalopathy and poorer survival.

BACKGROUND AND AIMS: Minimal hepatic encephalopathy (MHE) is a frequent complication in patients with liver cirrhosis. Its impact on predicting the development of overt hepatic encephalopathy (OHE) and survival has not been studied in large multicenter studies. METHODS: Data from patients recruited at eight centers across Europe and the United States were analyzed. MHE was detected using the psychometric hepatic encephalopathy score (PHES). A subset was also tested with the simplified animal naming test (S-ANT1). Patients were followed for OHE development and death/liver transplantation (LTx). RESULTS: A total of 1462 patients with a median model of end-stage liver disease of 11 were included (Child-Pugh (CP) stages: A 47%/B 41%/C 12%). Median follow-up time was 19 months, during which 336 (23%) patients developed an OHE episode and 464 (32%) reached the composite end point of death/LTx (369 deaths, 95 LTx). In multivariable analyses, MHE (defined by PHES) was associated with the development of OHE (subdistribution hazard ratio 1.74, p < 0.001) and poorer LTx-free survival (hazard ratio 1.53, p < 0.001) in the total cohort as well as in the subgroup of patients without a history of OHE. In subgroup analyses, MHE (defined by PHES) was associated with OHE development in patients with CP B, whereas there was no association in patients with CP A or C. In the subgroup of patients with available S-ANT1, MHE (defined by S-ANT1) was independently associated with OHE development. Combined testing (PHES+S-ANT1) was superior to single testing for predicting OHE and poorer LTx-free survival. CONCLUSIONS: This large multicenter study demonstrates that screening for MHE is a useful tool for predicting OHE and poorer survival.

Prevalence of Minimal Hepatic Encephalopathy in Patients With Liver Cirrhosis: A Multicenter Study.

INTRODUCTION: The prevalence of minimal hepatic encephalopathy (MHE), in particular in different subgroups, remains unknown. This study aimed to analyze the prevalence of MHE in different subgroups to identify patients at high risk and to pave the way for personalized screening approaches. METHODS: In this study, data of patients recruited at 10 centers across Europe and the United States were analyzed. Only patients without clinical signs of hepatic encephalopathy were included. MHE was detected using the Psychometric Hepatic Encephalopathy Score (PHES, cut-off < or ≤-4 depending on local norms). Clinical and demographic characteristics of the patients were assessed and analyzed. RESULTS: In total, 1,868 patients with cirrhosis with a median model for end-stage liver disease (MELD) of 11 were analyzed (Child-Pugh [CP] stages: A 46%, B 42%, and C 12%). In the total cohort, MHE was detected by PHES in 650 patients (35%). After excluding patients with a history of overt hepatic encephalopathy, the prevalence of MHE was 29%. In subgroup analyses, the prevalence of MHE in patients with CP A was low (25%), whereas it was high in CP B or C (42% and 52%). In patients with a MELD score <10, the prevalence of MHE was only 25%, but it was 48% in patients with a MELD score ≥20. Standardized ammonia levels (ammonia level/upper limit of normal of each center) correlated significantly, albeit weakly with PHES (Spearman ρ = -0.16, P < 0.001). DISCUSSION: The prevalence of MHE in patients with cirrhosis was high but varied substantially between diseases stages. These data may pave the way for more individualized MHE screening approaches.

Differential Effects of Somatostatin, Octreotide, and Lanreotide on Neuroendocrine Differentiation and Proliferation in Established and Primary NET Cell Lines: Possible Crosstalk with TGF-ß 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)-ß. 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-ß1 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-ß1 treatment with induction of expression of SST and SSTR2/5. Of note, the ability of NT-3 cells to respond to TGF-ß1 with upregulation of the established TGF-ß 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-ß1 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-ß treatment and thus provide circumstantial evidence that crosstalk of SST and TGF-ß signaling is not confined to BON cells but is a general feature of panNETs.

Urinary ethyl glucuronide (uEtG) as a marker for alcohol consumption in liver transplant candidates: a real-world cohort.

BACKGROUND: In order to reduce alcohol relapse after liver transplantation (LT), the German national guidelines for waiting-list maintenance and organ allocation demand a minimum 6-month period of alcohol abstinence pre-LT, confirmed by measuring urinary ethyl glucuronide (uEtG). METHODS: Between January 2015 and June 2016, uEtG was measured at least once in 339 cirrhotic patients with an indication for LT at the University Medical Center Mainz. uEtG was measured with an enzyme-linked immunosorbent assay (ELISA) screening test (cutoff value: 500 µg/L). For uEtG values ≥ 500 µg/L, liquid chromatography-mass spectrometry (LC-MS/MS) was performed as a confirmatory assay. Data were collected prospectively in a transplant database. RESULTS: Of the 339 potential liver transplant candidates, uEtG was negative in 86.4 %. Most patients were male (64.3 %), with an average age of 56.42 ±â€Š10.1 years. In the multivariate analysis, mean corpuscular volume (p = 0.001), urinary creatinine (p = 0.001), gamma-glutamyl transferase (p = 0.001), and hemoglobin (p = 0.003) were significantly associated with a positive uEtG test result. The sensitivity of the ELISA screening test was 100 % for uEtG values > 2000 µg/L, as confirmed by LC-MS/MS. CONCLUSION: uEtG is an effective parameter to reveal alcohol consumption by patients on the waiting list for LT. The sensitivity of the ELISA is excellent for uEtG values > 2000 µg/L, for which LC-MS/MS confirmation could be omitted.

RAC1b Collaborates with TAp73α-SMAD4 Signaling to Induce Biglycan Expression and Inhibit Basal and TGF-ß-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)-ß. Data from mouse models of pancreatic cancer have revealed that transcriptionally active p73 (TAp73) impacts the TGF-ß 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-ß1 on BGN. TAp73-mediated regulation of BGN, and inhibition of TGF-ß 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-ß1-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-ß 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.

Inhibition of PRMT5-mediated regulation of DKK1 sensitizes colorectal cancer cells to chemotherapy.

The Dickkopf family proteins (DKKs) are strong Wnt signaling antagonists that play a significant role in colorectal cancer (CRC) development and progression. Recent work has shown that DKKs, mainly DKK1, are associated with the induction of chemoresistance in CRC and that DKK1 expression in cancer cells correlates with that of protein arginine N-methyltransferase 5 (PRMT5). This points to the presence of a regulatory loop between DKK1 and PRMT5. Herein, we addressed the question of whether PRMT5 contributes to DKK1 expression in CRC and hence CRC chemoresistance. Both in silico and in vitro approaches were used to explore the relationship between PRMT5 and different DKK members. Our data demonstrated that DKK1 expression is significantly upregulated in CRC clinical samples, KRAS-mutated CRC in particular and that the levels of DKK1 positively correlate with PRMT5 activation. Chromatin immunoprecipitation (ChIP) data indicated a possible epigenetic role of PRMT5 in regulating DKK1, possibly through the symmetric dimethylation of H3R8. Knockdown of DKK1 or treatment with the PRMT5 inhibitor CMP5 in combination with doxorubicin yielded a synergistic anti-tumor effect in KRAS mutant, but not KRAS wild-type, CRC cells. These findings suggest that PRMT5 regulates DKK1 expression in CRC and that inhibition of PRMT5 modulates DKK1 expression in such a way that reduces CRC cell growth.

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.

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.

Proton pump inhibitor use and risk of hepatic encephalopathy: A multicentre study.

Background & Aims: Data on the association between proton pump inhibitor (PPI) use and hepatic encephalopathy (HE) are conflicting, and data from multicentre studies are scarce. The aim of this study was to dissect the potential association between PPI use and minimal (MHE) and overt HE (OHE). Methods: Data from patients with cirrhosis recruited at seven centres across Europe and the US were analysed. MHE was defined by the psychometric hepatic encephalopathy score (PHES). PPI use was recorded on the day of testing with PHES. Patients were followed for OHE development and death/liver transplantation. Results: A total of 1,160 patients with a median MELD of 11 were included (Child-Pugh stages: A 49%/B 39%/C 11%). PPI use was noted in 58% of patients. Median follow-up time was 18.1 months, during which 230 (20%) developed an OHE episode, and 224 (19%) reached the composite endpoint of death/liver transplantation. In multivariable analyses, PPI use was neither associated with the presence of MHE at baseline nor OHE development during follow-up. These findings were consistent in subgroup analyses of patients with Child-Pugh A or B cirrhosis and after excluding patients with a history of OHE. PPI use was also not associated with a higher risk of OHE, neither in patients with an indication for treatment nor in patients without an indication. Conclusions: PPI use is not associated with a higher risk of HE in patients with cirrhosis. Based on these findings, at present, a prescription should not be prohibited in case of a generally accepted indication. Impact and implications: Data on the association between proton pump inhibitor (PPI) use and hepatic encephalopathy (HE) are conflicting. In this study, PPI use was not associated with a higher risk of minimal HE at baseline or overt HE during follow-up in patients with cirrhosis. Based on these findings, prescription of a PPI for a generally accepted indication should not be prohibited in patients with cirrhosis.

PHES scores have limited impact on the risk of overt HE in patients with minimal HE.

BACKGROUND: Minimal hepatic encephalopathy, defined by the portosystemic hepatic encephalopathy score (PHES), is associated with a higher risk of subsequent OHE. It remains unclear if there is a stepwise increase in OHE risk with worse PHES results. METHODS: In this multicenter study, patients with minimal hepatic encephalopathy, as defined by abnormal PHES, were followed for OHE development. RESULTS: In all, 207 patients were included. There was no stepwise increase in OHE risk with worse PHES results. CONCLUSIONS: Abnormal PHES is associated with a higher OHE risk, but we found no stepwise increase in OHE risk with worse PHES results below the established cutoff.

Elucidation of the Role of SMAD4 in Epithelial-Mesenchymal Plasticity: Does It Help to Better Understand the Consequences of DPC4 Inactivation in the Malignant Progression of Pancreatic Ductal Adenocarcinoma?

Pancreatic ductal adenocarcinoma (PDAC) is the 4th leading cause of cancer-related mortality worldwide, with a 5-year-survival rate below 10% that is the lowest of all cancer types [...].

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)-ß. 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-ß/Smad signaling, while preventing non-canonical TGF-ß 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-ß1-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 ß 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-ß-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.

Elevated serum levels of glial fibrillary acidic protein are associated with covert hepatic encephalopathy in patients with cirrhosis.

Background & Aims: Blood biomarkers facilitating the diagnosis of covert hepatic encephalopathy (CHE) in patients with cirrhosis are lacking. Astrocyte swelling is a major component of hepatic encephalopathy. Thus, we hypothesised that glial fibrillary acidic protein (GFAP), the major intermediate filament of astrocytes, might facilitate early diagnosis and management. This study aimed to investigate the utility of serum GFAP (sGFAP) levels as a biomarker of CHE. Methods: In this bicentric study, 135 patients with cirrhosis, 21 patients with ongoing harmful alcohol use and cirrhosis, and 15 healthy controls were recruited. CHE was diagnosed using psychometric hepatic encephalopathy score. sGFAP levels were measured using a highly sensitive single-molecule array (SiMoA) immunoassay. Results: In total, 50 (37%) people presented with CHE at study inclusion. Participants with CHE displayed significantly higher sGFAP levels than those without CHE (median sGFAP, 163 pg/ml [IQR 136; 268] vs. 106 pg/ml [IQR 75; 153]; p <0.001) or healthy controls (p <0.001). sGFAP correlated with results in psychometric hepatic encephalopathy score (Spearman's ρ = -0.326, p <0.001), model for end-stage liver disease score (Spearman's ρ = 0.253, p = 0.003), ammonia (Spearman's ρ = 0.453, p = 0.002), and IL-6 serum levels (Spearman's ρ = 0.323, p = 0.006). Additionally, sGFAP levels were independently associated with the presence of CHE in multivariable logistic regression analysis (odds ratio 1.009; 95% CI 1.004-1.015; p <0.001). sGFAP levels did not differ between patients with alcohol-related cirrhosis vs. patients with non-alcohol-related cirrhosis or between patients with ongoing alcohol use vs. patients with discontinued alcohol use.Conclusions: sGFAP levels are associated with CHE in patients with cirrhosis. These results suggest that astrocyte injury may already occur in patients with cirrhosis and subclinical cognitive deficits and that sGFAP could be explored as a novel biomarker. Impact and implications: Blood biomarkers facilitating the diagnosis of covert hepatic encephalopathy (CHE) in patients with cirrhosis are lacking. In this study, we were able to demonstrate that sGFAP levels are associated with CHE in patients with cirrhosis. These results suggest that astrocyte injury may already occur in patients with cirrhosis and subclinical cognitive deficits and that sGFAP could be explored as a novel biomarker.

Markers of cell death predict therapy response in patients with cirrhosis and hepatorenal syndrome.

BACKGROUND AND AIMS: Hepatorenal syndrome is a major complication in patients with cirrhosis and associated with high mortality. Predictive biomarkers for therapy response are largely missing. Cytokeratin18-based cell death markers are significantly elevated in patients with complications of chronic liver disease, but the role of these markers in patients with HRS treated with vasoconstrictors and albumin is unknown. METHODS: We prospectively analyzed a total of 138 patients with HRS, liver cirrhosis without HRS and acute kidney injury treated at the University Medical Center Mainz between April 2013 and July 2018. Serum levels of M30 and M65 were analyzed by ELISA and clinical data were collected. Predictive ability was assessed by Kaplan-Meier curves, logistic regression and c-statistic. Primary endpoint was response to therapy. RESULTS: M30 and M65 were significantly increased in patients with HRS compared to non-HRS controls (M30: p < 0.0001; M65: p < 0.0001). Both serum markers showed predictive ability for dialysis- and LTX-free survival but not overall survival. Logistic regression confirmed M30 and M65 as independent prognostic factors for response to therapy. A novel predictive score comprising bilirubin and M65 showed highest predictive ability to predict therapy response. CONCLUSIONS: Serum levels of M30 and M65 can robustly discriminate patients into responders and non-responders to terlipressin therapy with a good predictive ability for dialysis- and LTX-free survival in cirrhotic patients. Cell death parameters might possess clinical relevance in patients with liver cirrhosis and HRS.

Establishment and Molecular Characterization of Two Patient-Derived Pancreatic Ductal Adenocarcinoma Cell Lines as Preclinical Models for Treatment Response.

The prognosis of pancreatic ductal adenocarcinoma (PDAC) is exceedingly poor. Although surgical resection is the only curative treatment option, multimodal treatment is of the utmost importance, as only about 20% of tumors are primarily resectable at the time of diagnosis. The choice of chemotherapeutic treatment regimens involving gemcitabine and FOLFIRINOX is currently solely based on the patient's performance status, but, ideally, it should be based on the tumors' individual biology. We established two novel patient-derived primary cell lines from surgical PDAC specimens. LuPanc-1 and LuPanc-2 were derived from a pT3, pN1, G2 and a pT3, pN2, G3 tumor, respectively, and the clinical follow-up was fully annotated. STR-genotyping revealed a unique profile for both cell lines. The population doubling time of LuPanc-2 was substantially longer than that of LuPanc-1 (84 vs. 44 h). Both cell lines exhibited a typical epithelial morphology and expressed moderate levels of CK7 and E-cadherin. LuPanc-1, but not LuPanc-2, co-expressed E-cadherin and vimentin at the single-cell level, suggesting a mixed epithelial-mesenchymal differentiation. LuPanc-1 had a missense mutation (p.R282W) and LuPanc-2 had a frameshift deletion (p.P89X) in TP53. BRCA2 was nonsense-mutated (p.Q780*) and CREBBP was missense-mutated (p.P279R) in LuPanc-1. CDKN2A was missense-mutated (p.H83Y) in LuPanc-2. Notably, only LuPanc-2 harbored a partial or complete deletion of DPC4. LuPanc-1 cells exhibited high basal and transforming growth factor (TGF)-ß1-induced migratory activity in real-time cell migration assays, while LuPanc-2 was refractory. Both LuPanc-1 and LuPanc-2 cells responded to treatment with TGF-ß1 with the activation of SMAD2; however, only LuPanc-1 cells were able to induce TGF-ß1 target genes, which is consistent with the absence of DPC4 in LuPanc-2 cells. Both cell lines were able to form spheres in a semi-solid medium and in cell viability assays, LuPanc-1 cells were more sensitive than LuPanc-2 cells to treatment with gemcitabine and FOLFIRINOX. In summary, both patient-derived cell lines show distinct molecular phenotypes reflecting their individual tumor biology, with a unique clinical annotation of the respective patients. These preclinical ex vivo models can be further explored for potential new treatment strategies and might help in developing personalized (targeted) therapy regimens.

Suppressive Role of ACVR1/ALK2 in Basal and TGFß1-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 ß1 (TGFß1). The involvement of at least two type I receptors, ALK5 and ALK2, that transmit downstream signals of the TGFß 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 TGFß1 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 TGFß1-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 TGFß-rich tumor microenvironment.

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

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)ß1 in regard to regulation of growth and individual TGFß target genes, and to culture conditions that favour ductal-to-endocrine transdifferentiation as a more direct measure for cellular plasticity. Of note, stimulation with TGFß1 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, IL1ß 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 TGFß1 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.

Outcomes in patients receiving palliative chemotherapy for advanced biliary tract cancer.

BACKGROUND & AIMS: Advanced biliary tract cancer (ABTC) is associated with a poor prognosis. Real-world data on the outcome of patients with ABTC undergoing sequential chemotherapies remain scarce, and little is known about treatment options beyond the established first- and second-line treatments with gemcitabine + cisplatin and FOLFOX. This study aimed to evaluate the outcome of patients with regard to different oncological therapies and to identify prognostic factors. METHODS: From January 2010 until December 2019, 142 patients started palliative chemotherapy at our tertiary care liver center. Overall survival (OS) was calculated using Kaplan-Meier plots. Prognostic factors were evaluated using cox proportional-hazards. RESULTS: Patients received a median number of 2 lines of chemotherapy. Median OS was 6.7, 15.2 and 18.2 months for patients who received 1, 2 and 3 lines of chemotherapy, respectively. Patients treated with FOLFIRINOX had a significantly extended OS of 23.8 months (log-rank test: p = 0.018). The univariate cox regression analysis identified several clinical parameters associated with survival (e.g. albumin, bilirubin, carcinoembryonic antigen, carbohydrate antigen 19-9 levels). CONCLUSIONS: Our study provides real-world data on the prognosis of ABTC including survival times for patients receiving third and later lines of chemotherapy. LAY SUMMARY: Real-world data depicting the outcome of patients with advanced biliary tract cancer outside the framework of controlled trials remain rare despite being extremely important for clinical decision-making. This study therefore provides important real-world data on the established first- and second-line treatments with gemcitabine + cisplatin and FOLFOX, as well as on other chemotherapy regimens or later lines of chemotherapy. It further demonstrates that the use of FOLFIRINOX is associated with promising survival and that there is an association between various clinical parameters such as pre-therapeutic albumin, bilirubin or carbohydrate antigen 19-9 levels and survival.

13 C-Methacetin Breath Test Predicts Survival in Patients With Hepatocellular Carcinoma Undergoing Transarterial Chemoembolization.

INTRODUCTION: The 13 C-methacetin breath test ( 13 C-MBT) is a dynamic method for assessing liver function. This proof-of-concept study aimed to investigate the association between 13 C-MBT values and outcomes in patients with hepatocellular carcinoma (HCC) undergoing transarterial chemoembolization (TACE). METHODS: A total of 30 patients with HCC were prospectively recruited. Of these, 25 were included in baseline and 20 in longitudinal analysis. 13 C-MBTs were performed before the first and second TACE session. Patients were followed for at least 1 year. RESULTS: At baseline, the median 13 C-MBT value was 261 µg/kg/hr (interquartile range 159-387). 13 C-MBT, albumin-bilirubin, Child-Pugh, and Model for End-Stage Liver Disease scores were associated with overall survival in extended univariable Cox regression ( 13 C-MBT: standardized hazard ratio [sHR] 0.297, 95% confidence interval [CI] 0.111-0.796; albumin-bilirubin score: sHR 4.051, 95% CI 1.813-9.052; Child-Pugh score: sHR 2.616, 95% CI 1.450-4.719; Model for End-Stage Liver Disease score: sHR 2.781, 95% CI 1.356-5.703). Using a cutoff of 140 µg/kg/hr at baseline, 13 C-MBT was associated with prognosis (median overall survival 28.5 months [95% CI 0.0-57.1] vs 3.5 months [95% CI 0.0-8.1], log-rank P < 0.001). Regarding prediction of 90-day mortality after second 13 C-MBT, the relative change in 13 C-MBT values yielded an area under the receiver-operating characteristic curve of 1.000 ( P = 0.007). DISCUSSION: Baseline and longitudinal 13 C-MBT values predict survival of patients with HCC undergoing TACE. The relative change in 13 C-MBT values predicts short-term mortality and may assist in identifying patients who will not benefit from further TACE treatment.