Nucleotide metabolism in cancer cells fuels a UDP-driven macrophage cross-talk, promoting immunosuppression and immunotherapy resistance.

Many individuals with cancer are resistant to immunotherapies. Here, we identify the gene encoding the pyrimidine salvage pathway enzyme cytidine deaminase (CDA) among the top upregulated metabolic genes in several immunotherapy-resistant tumors. We show that CDA in cancer cells contributes to the uridine diphosphate (UDP) pool. Extracellular UDP hijacks immunosuppressive tumor-associated macrophages (TAMs) through its receptor P2Y6. Pharmacologic or genetic inhibition of CDA in cancer cells (or P2Y6 in TAMs) disrupts TAM-mediated immunosuppression, promoting cytotoxic T cell entry and susceptibility to anti-programmed cell death protein 1 (anti-PD-1) treatment in resistant pancreatic ductal adenocarcinoma (PDAC) and melanoma models. Conversely, CDA overexpression in CDA-depleted PDACs or anti-PD-1-responsive colorectal tumors or systemic UDP administration (re)establishes resistance. In individuals with PDAC, high CDA levels in cancer cells correlate with increased TAMs, lower cytotoxic T cells and possibly anti-PD-1 resistance. In a pan-cancer single-cell atlas, CDAhigh cancer cells match with T cell cytotoxicity dysfunction and P2RY6high TAMs. Overall, we suggest CDA and P2Y6 as potential targets for cancer immunotherapy.

Transcriptomic characterization of the histopathological growth patterns in breast cancer liver metastases.

Metastatic breast cancer (mBC) remains incurable and liver metastases (LM) are observed in approximately 50% of all patients with mBC. In some cases, surgical resection of breast cancer liver metastases (BCLM) is associated with prolonged survival. However, there are currently no validated marker to identify these patients. The interactions between the metastatic cancer cells and the liver microenvironment result in two main histopathological growth patterns (HGP): replacement (r-HGP), characterized by a direct contact between the cancer cells and the hepatocytes, and desmoplastic (d-HGP), in which a fibrous rim surrounds the tumor cells. In patients who underwent resection of BCLM, the r-HGP is associated with a worse postoperative prognosis than the d-HGP. Here, we aim at unraveling the biological differences between these HGP within ten patients presenting both HGP within the same metastasis. The transcriptomic analyses reveal overexpression of genes involved in cell cycle, DNA repair, vessel co-option and cell motility in r-HGP while angiogenesis, wound healing, and several immune processes were found overexpressed in d-HGP LM. Understanding the biology of the LM could open avenues to refine treatment of BC patients with LM.

Higher Postoperative Mortality and Inferior Survival After Right-Sided Liver Resection for Perihilar Cholangiocarcinoma: Left-Sided Resection is Preferred When Possible.

BACKGROUND: A right- or left-sided liver resection can be considered in about half of patients with perihilar cholangiocarcinoma (pCCA), depending on tumor location and vascular involvement. This study compared postoperative mortality and long-term survival of right- versus left-sided liver resections for pCCA. METHODS: Patients who underwent major liver resection for pCCA at 25 Western centers were stratified according to the type of hepatectomy-left, extended left, right, and extended right. The primary outcomes were 90-day mortality and overall survival (OS). RESULTS: Between 2000 and 2022, 1701 patients underwent major liver resection for pCCA. The 90-day mortality was 9% after left-sided and 18% after right-sided liver resection (p < 0.001). The 90-day mortality rates were 8% (44/540) after left, 11% (29/276) after extended left, 17% (51/309) after right, and 19% (108/576) after extended right hepatectomy (p < 0.001). Median OS was 30 months (95% confidence interval [CI] 27-34) after left and 23 months (95% CI 20-25) after right liver resection (p < 0.001), and 33 months (95% CI 28-38), 27 months (95% CI 23-32), 25 months (95% CI 21-30), and 21 months (95% CI 18-24) after left, extended left, right, and extended right hepatectomy, respectively (p < 0.001). A left-sided resection was an independent favorable prognostic factor for both 90-day mortality and OS compared with right-sided resection, with similar results after excluding 90-day fatalities. CONCLUSIONS: A left or extended left hepatectomy is associated with a lower 90-day mortality and superior OS compared with an (extended) right hepatectomy for pCCA. When both a left and right liver resection are feasible, a left-sided liver resection is preferred.

Predicting futility of upfront surgery in perihilar cholangiocarcinoma: Machine learning analytics model to optimize treatment allocation.

BACKGROUND: While resection remains the only curative option for perihilar cholangiocarcinoma, it is well known that such surgery is associated with a high risk of morbidity and mortality. Nevertheless, beyond facing life-threatening complications, patients may also develop early disease recurrence, defining a "futile" outcome in perihilar cholangiocarcinoma surgery. The aim of this study is to predict the high-risk category (futile group) where surgical benefits are reversed and alternative treatments may be considered. METHODS: The study cohort included prospectively maintained data from 27 Western tertiary referral centers: the population was divided into a development and a validation cohort. The Framingham Heart Study methodology was used to develop a preoperative scoring system predicting the "futile" outcome. RESULTS: A total of 2271 cases were analyzed: among them, 309 were classified within the "futile group" (13.6%). American Society of Anesthesiology (ASA) score ≥ 3 (OR 1.60; p = 0.005), bilirubin at diagnosis ≥50 mmol/L (OR 1.50; p = 0.025), Ca 19-9 ≥ 100 U/mL (OR 1.73; p = 0.013), preoperative cholangitis (OR 1.75; p = 0.002), portal vein involvement (OR 1.61; p = 0.020), tumor diameter ≥3 cm (OR 1.76; p < 0.001), and left-sided resection (OR 2.00; p < 0.001) were identified as independent predictors of futility. The point system developed, defined three (ie, low, intermediate, and high) risk classes, which showed good accuracy (AUC 0.755) when tested on the validation cohort. CONCLUSIONS: The possibility to accurately estimate, through a point system, the risk of severe postoperative morbidity and early recurrence, could be helpful in defining the best management strategy (surgery vs. nonsurgical treatments) according to preoperative features.

Adipose tissue macrophage dysfunction is associated with a breach of vascular integrity in NASH.

BACKGROUND & AIMS: In non-alcoholic fatty liver disease (NAFLD), monocytes infiltrate visceral adipose tissue promoting local and hepatic inflammation. However, it remains unclear what drives inflammation and how the immune landscape in adipose tissue differs across the NAFLD severity spectrum. We aimed to assess adipose tissue macrophage (ATM) heterogeneity in a NAFLD cohort. METHODS: Visceral adipose tissue macrophages from lean and obese patients, stratified by NAFLD phenotypes, underwent single-cell RNA sequencing. Adipose tissue vascular integrity and breaching was assessed on a protein level via immunohistochemistry and immunofluorescence to determine targets of interest. RESULTS: We discovered multiple ATM populations, including resident vasculature-associated macrophages (ResVAMs) and distinct metabolically active macrophages (MMacs). Using trajectory analysis, we show that ResVAMs and MMacs are replenished by a common transitional macrophage (TransMac) subtype and that, during NASH, MMacs are not effectively replenished by TransMac precursors. We postulate an accessory role for MMacs and ResVAMs in protecting the adipose tissue vascular barrier, since they both interact with endothelial cells and localize around the vasculature. However, across the NAFLD severity spectrum, alterations occur in these subsets that parallel an adipose tissue vasculature breach characterized by albumin extravasation into the perivascular tissue. CONCLUSIONS: NAFLD-related macrophage dysfunction coincides with a loss of adipose tissue vascular integrity, providing a plausible mechanism by which tissue inflammation is perpetuated in adipose tissue and downstream in the liver. IMPACT AND IMPLICATIONS: Our study describes for the first time the myeloid cell landscape in human visceral adipose tissue at single-cell level within a cohort of well-characterized patients with non-alcoholic fatty liver disease. We report unique non-alcoholic steatohepatitis-specific transcriptional changes within metabolically active macrophages (MMacs) and resident vasculature-associated macrophages (ResVAMs) and we demonstrate their spatial location surrounding the vasculature. These dysfunctional transcriptional macrophage states coincided with the loss of adipose tissue vascular integrity, providing a plausible mechanism by which tissue inflammation is perpetuated in adipose tissue and downstream in the liver. Our study provides a theoretical basis for new therapeutic strategies to be directed towards reinstating the endogenous metabolic, homeostatic and cytoprotective functions of ResVAMs and MMacs, including their role in protecting vascular integrity.

Histopathological growth patterns and tumor-infiltrating lymphocytes in breast cancer liver metastases.

Liver is the third most common organ for breast cancer (BC) metastasis. Two main histopathological growth patterns (HGP) exist in liver metastases (LM): desmoplastic and replacement. Although a reduced immunotherapy efficacy is reported in patients with LM, tumor-infiltrating lymphocytes (TIL) have not yet been investigated in BCLM. Here, we evaluate the distribution of the HGP and TIL in BCLM, and their association with clinicopathological variables and survival. We collect samples from surgically resected BCLM (n = 133 patients, 568 H&E sections) and post-mortem derived BCLM (n = 23 patients, 97 H&E sections). HGP is assessed as the proportion of tumor liver interface and categorized as pure-replacement ('pure r-HGP') or any-desmoplastic ('any d-HGP'). We score the TIL according to LM-specific guidelines. Associations with progression-free (PFS) and overall survival (OS) are assessed using Cox regressions. We observe a higher prevalence of 'any d-HGP' (56%) in the surgical samples and a higher prevalence of 'pure r-HGP' (83%) in the post-mortem samples. In the surgical cohort, no evidence of the association between HGP and clinicopathological characteristics is observed except with the laterality of the primary tumor (p value = 0.049) and the systemic preoperative treatment before liver surgery (p value = .039). TIL is less prevalent in 'pure r-HGP' as compared to 'any d-HGP' (p value = 0.001). 'Pure r-HGP' predicts worse PFS (HR: 2.65; CI: (1.45-4.82); p value = 0.001) and OS (HR: 3.10; CI: (1.29-7.46); p value = 0.011) in the multivariable analyses. To conclude, we demonstrate that BCLM with a 'pure r-HGP' is associated with less TIL and with the worse outcome when compared with BCLM with 'any d-HGP'. These findings suggest that HGP could be considered to refine treatment approaches.

PD-1- CD45RA+ effector-memory CD8 T cells and CXCL10+ macrophages are associated with response to atezolizumab plus bevacizumab in advanced hepatocellular carcinoma.

The combination of atezolizumab plus bevacizumab (atezo/bev) has dramatically changed the treatment landscape of advanced HCC (aHCC), achieving durable responses in some patients. Using single-cell transcriptomics, we characterize the intra-tumoural and peripheral immune context of patients with aHCC treated with atezo/bev. Tumours from patients with durable responses are enriched for PDL1+ CXCL10+ macrophages and, based on cell-cell interaction analysis, express high levels of CXCL9/10/11 and are predicted to attract peripheral CXCR3+ CD8+ effector-memory T cells (CD8 TEM) into the tumour. Based on T cell receptor sharing and pseudotime trajectory analysis, we propose that CD8 TEM preferentially differentiate into clonally-expanded PD1- CD45RA+ effector-memory CD8+ T cells (CD8 TEMRA) with pronounced cytotoxicity. In contrast, in non-responders, CD8 TEM remain frozen in their effector-memory state. Finally, in responders, CD8 TEMRA display a high degree of T cell receptor sharing with blood, consistent with their patrolling activity. These findings may help understand the possible mechanisms underlying response to atezo/bev in aHCC.

Coronary covered stents in the management of late-onset arterial complications post-hepato-pancreato-biliary surgery.

PURPOSE: To retrospectively evaluate the safety, efficacy, and late clinical outcome of coronary covered stent placement for the treatment of late-onset arterial complications after hepato-pancreato-biliary surgery. MATERIALS AND METHODS: Consecutive patients presenting with post-hepato-pancreato-biliary surgery-related arterial lesions and subsequently treated with a covered coronary stent in the authors institution between January 2012 and November 2021 were included. Primary endpoints were technical and clinical success; secondary endpoints were covered stent patency and end-organ perfusion of the affected artery. RESULTS: The study included 22 patients (13 men and 9 women) with a mean age of 67 years ± 9.6 years. Initial surgery included pancreaticoduodenectomy (n = 15; 68%), liver transplantation (n = 2; 9%), left hepatectomy (n = 1; 5%), bile duct resection (n = 1; 5%), hepatogastrostomy (n = 1; 5%), and segmental enterectomy (n = 1; 5%). Technically, coronary covered stents were successfully placed in n = 22 patients (100%) without immediate complication. Definitive bleeding control was observed in n = 18 patients (81.1%) with recurrent bleeding within 30 days postintervention in n = 5 patients (23%). No ischemic liver or biliary complications occurred during the follow-up period. The 30-day mortality rate was 0%. CONCLUSION: Coronary covered stents are a safe and efficient treatment option in most of the patients presenting with late-onset postoperative arterial injuries following hepato-pancreato-biliary surgery and are associated with an acceptable recurrent bleeding rate and no late, ischemic, parenchymal complications.

Same-session double EUS-guided bypass versus surgical gastroenterostomy and hepaticojejunostomy: an international multicenter comparison.

BACKGROUND AND AIMS: Gastric outlet and biliary obstruction are common manifestations of GI malignancies and some benign diseases for which standard treatment would be surgical gastroenterostomy and hepaticojejunostomy (ie, "double bypass"). Therapeutic EUS has allowed for the creation of an EUS-guided double bypass. However, same-session double EUS-guided bypass has only been described in small proof-of-concept series and lacks a comparison with surgical double bypass. METHODS: A retrospective multicenter analysis was performed of all consecutive same-session double EUS-guided bypass procedures performed in 5 academic centers. Surgical comparators were extracted from these centers' databases from the same time interval. Efficacy, safety, hospital stay, nutrition and chemotherapy resumption, long-term patency, and survival were compared. RESULTS: Of 154 identified patients, 53 (34.4%) received treatment with EUS and 101 (65.6%) with surgery. At baseline, patients undergoing EUS exhibited higher American Society of Anesthesiologists scores and a higher median Charlson Comorbidity Index (9.0 [interquartile range {IQR}, 7.0-10.0] vs 7.0 [IQR, 5.0-9.0], P < .001). Technical success (96.2% vs 100%, P = .117) and clinical success rates (90.6% vs 82.2%, P = .234) were similar when comparing EUS and surgery. Overall (11.3% vs 34.7%, P = .002) and severe adverse events (3.8% vs 19.8%, P = .007) occurred more frequently in the surgical group. In the EUS group, median time to oral intake (0 days [IQR, 0-1] vs 6 days [IQR, 3-7], P < .001) and hospital stay (4.0 days [IQR, 3-9] vs 13 days [IQR, 9-22], P < .001) were significantly shorter. CONCLUSIONS: Despite being used in a patient population with more comorbidities, same-session double EUS-guided bypass achieved similar technical and clinical success and was associated with fewer overall and severe adverse events when compared with surgical gastroenterostomy and hepaticojejunostomy.

Multivariable prediction model for both 90-day mortality and long-term survival for individual patients with perihilar cholangiocarcinoma: does the predicted survival justify the surgical risk?

BACKGROUND: The risk of death after surgery for perihilar cholangiocarcinoma is high; nearly one in every five patients dies within 90 days after surgery. When the oncological benefit is limited, a high-risk resection may not be justified. This retrospective cohort study aimed to create two preoperative prognostic models to predict 90-day mortality and overall survival (OS) after major liver resection for perihilar cholangiocarcinoma. METHODS: Separate models were built with factors known before surgery using multivariable regression analysis for 90-day mortality and OS. Patients were categorized in three groups: favourable profile for surgical resection (90-day mortality rate below 10 per cent and predicted OS more than 3 years), unfavourable profile (90-day mortality rate above 25 per cent and/or predicted OS below 1.5 years), and an intermediate group. RESULTS: A total of 1673 patients were included. Independent risk factors for both 90-day mortality and OS included ASA grade III-IV, large tumour diameter, and right-sided hepatectomy. Additional risk factors for 90-day mortality were advanced age and preoperative cholangitis; those for long-term OS were high BMI, preoperative jaundice, Bismuth IV, and hepatic artery involvement. In total, 294 patients (17.6 per cent) had a favourable risk profile for surgery (90-day mortality rate 5.8 per cent and median OS 42 months), 271 patients (16.2 per cent) an unfavourable risk profile (90-day mortality rate 26.8 per cent and median OS 16 months), and 1108 patients (66.2 per cent) an intermediate risk profile (90-day mortality rate 12.5 per cent and median OS 27 months). CONCLUSION: Preoperative risk models for 90-day mortality and OS can help identify patients with resectable perihilar cholangiocarcinoma who are unlikely to benefit from surgical resection. Tailored shared decision-making is particularly essential for the large intermediate group.

Prospective cohort study on short-term outcomes of 3D-laparoscopic pancreaticoduodenectomy with stented pancreaticogastrostomy.

BACKGROUND: Minimally invasive pancreaticoduodenectomy, either laparoscopic or robotic, is a high-risk procedure with demanding learning curve. The aim of this prospective cohort study was to evaluate short-term clinical and oncologic outcomes of 3D-laparoscopic pancreaticoduodenectomy (3dLPD) with stented pancreaticogastrostomy (sPG) and Roux-en-Y gastroenterostomy (ryGES). METHODS: Between March 2016 and July 2021, 347 consecutive patients underwent 3dLPD for confirmed or suspected pancreatic or periampullary tumors. Pancreatic duct diameter measured 3 mm or less in 221 (64%) and pancreatic texture was soft in 191 (55%) patients. Simultaneous resection of the superior mesenteric or portal vein was performed in 52 (15%) patients. RESULTS: Postoperative complications were observed in 189 (54%) patients, with severe complications (Clavien-Dindo grade > 2) in 68 (20%) including 4 (1.2%) deaths. Clinically relevant pancreatic fistula (cPOPF) occurred in 88 (25%), hemorrhage in 25 (7%), and bile leakage in 10 (3%) patients. Clinical pancreatic fistula was strongly associated with soft pancreatic texture and small pancreatic duct diameter (p < 0.001) and managed by endoscopic trans-gastric drainage in 34 (38.6%) patients, reoperation in 12 (13.6%), and ICU admission in 11 (12.5%). The remaining 31 (35%) patients with cPOPF were managed without invasive intervention. Median length of hospital stay after surgery was 13 (range 5-112; IQR 8-18) days. In pancreatic adenocarcinoma (PDAC) the R0-resection rate was 66/186 (36%), R1-indirect 95/186 (51%), and R1-direct 25 (13%). Median number of locoregional lymph nodes retrieved in PDAC was 21 (IQR 15-28). R0-resection rate for malignancy other than PDAC was 78/86 (91%) with a median of 16 (IQR 12-22) locoregional lymph nodes retrieved. CONCLUSION: 3dLPD with sPG and ryGES is associated with 1.2% mortality and 25% cPOPF. About two-third of patients with cPOPF were managed with some type of invasive intervention, whereas the intraoperatively placed drains sufficed in one-third of patients. CLINICAL TRIAL REGISTRY: Clinicaltrials.gov NCT02671357.

Targeting the bicarbonate transporter SLC4A4 overcomes immunosuppression and immunotherapy resistance in pancreatic cancer.

Solid tumors are generally characterized by an acidic tumor microenvironment (TME) that favors cancer progression, therapy resistance and immune evasion. By single-cell RNA-sequencing analysis in individuals with pancreatic ductal adenocarcinoma (PDAC), we reveal solute carrier family 4 member 4 (SLC4A4) as the most abundant bicarbonate transporter, predominantly expressed by epithelial ductal cells. Functionally, SLC4A4 inhibition in PDAC cancer cells mitigates the acidosis of the TME due to bicarbonate accumulation in the extracellular space and a decrease in lactate production by cancer cells as the result of reduced glycolysis. In PDAC-bearing mice, genetic or pharmacological SLC4A4 targeting improves T cell-mediated immune response and breaches macrophage-mediated immunosuppression, thus inhibiting tumor growth and metastases. In addition, Slc4a4 targeting in combination with immune checkpoint blockade is able to overcome immunotherapy resistance and prolong survival. Overall, our data propose SLC4A4 as a therapeutic target to unleash an antitumor immune response in PDAC.

Survival After Minimally Invasive vs Open Surgery for Pancreatic Adenocarcinoma.

Importance: Only a few high-volume centers have reported on long-term oncologic outcomes after minimally invasive pancreatic surgery (MIPS) for pancreatic adenocarcinoma, but none of them have shown superior long-term overall survival (OS) compared with open pancreatic surgery (OPS). Objective: To study long-term survival after MIPS and OPS with curative intent among patients with pancreatic adenocarcinoma. Design, Setting, and Participants: This comparative effectiveness study used a retrospective analysis of a prospectively maintained electronic database of patient data collected between January 2010 and December 2019. Consecutive patients from a high-volume pancreatic cancer referral center were included. Data analysis was conducted from March to October 2022. Median follow-up time was 56.8 months. Exposures: Patients were matched using propensity score models to study long-term survival. Main Outcomes and Measures: Survival outcomes were analyzed using the Cox proportional hazards model. Variables used for propensity score correction were TNM stage, tumor dimension, lymph node status, type of operation, simultaneous vascular resection, neoadjuvant chemotherapy, adjuvant chemotherapy, sex, age, and American Society of Anesthesiologists score. Additional corrections were made for year of surgery and type of adjuvant chemotherapy. Results: After propensity score matching the sample of 396 patients, there were 198 patients in the MIPS group (89 [44.9%] men; median [range] age, 68 [32-87] years) and 198 in the OPS group (94 [47.5%] men; median [range] age, 67 [39-84] years). Median OS in the MIPS group was 30.7 (95% CI, 26.2-36.8) months compared with 20.3 (95% CI, 17.6-23.5) months after OPS (hazard ratio [HR], 0.70; 95% CI, 0.56-0.87; P = .002). Median disease-free survival (DFS) after MIPS vs OPS was 14.8 (95% CI, 11.8-17.0) months vs 10.7 (95% CI, 9.0-12.1) months (HR, 0.71; 95% CI, 0.57-0.89; P = .003). Additional corrections for year of surgery and type of adjuvant chemotherapy showed better OS (year of surgery: HR, 0.74; 95% CI, 0.57-0.96; P = .02; adjuvant chemotherapy: HR, 0.71; 95% CI, 0.56-0.90; P = .005) and DFS (year of surgery: HR, 0.77; 95% CI, 0.59-0.99; P = .04; adjuvant chemotherapy: HR, 0.72; 95% CI, 0.57-0.92; P = .009) for patients undergoing minimally invasive vs open surgery. Conclusions and Relevance: In this study of 396 patients with borderline resectable and resectable pancreatic adenocarcinoma, MIPS was associated with better OS and DFS than OPS. Centralization of MIPS should be stimulated, and pancreatic surgeons should be encouraged to pass the learning curve before implementing MIPS for pancreatic adenocarcinoma in daily clinical practice.

Multi-institutional expert update on the use of laparoscopic bile duct exploration in the management of choledocholithiasis: Lesson learned from 3950 procedures.

BACKGROUND: Recently there has been a growing interest in the laparoscopic management of common bile duct stones with gallbladder in situ (LBDE), which is favoring the expansion of this technique. Our study identified the standardization factors of LBDE and its implementation in the single-stage management of choledocholithiasis. METHODS: A retrospective multi-institutional study among 17 centers with proven experience in LBDE was performed. A cross-sectional survey consisting of a semi-structured pretested questionnaire was distributed covering the main aspects on the use of LBDE in the management of choledocholithiasis. RESULTS: A total of 3950 LBDEs were analyzed. The most frequent indication was jaundice (58.8%). LBDEs were performed after failed ERCP in 15.2%. The most common approach used was the transcystic (63.11%). The overall series failure rate of LBDE was 4% and the median rate for each center was 6% (IQR, 4.5-12.5). Median operative time ranged between 60-120 min (70.6%). Overall morbidity rate was 14.6%, with a postoperative bile leak and complications ≥3a rate of 4.5% and 2.5%, respectively. The operative time decreased with experience (P = .03) and length of hospital stay was longer in the presence of a biliary leak (P = .04). Current training of LBDE was defined as poor or very poor by 82.4%. CONCLUSION: Based on this multicenter survey, LBDE is a safe and effective approach when performed by experienced teams. The generalization of LBDE will be based on developing training programs.

Endothelial Zeb2 preserves the hepatic angioarchitecture and protects against liver fibrosis.

AIMS: Hepatic capillaries are lined with specialized liver sinusoidal endothelial cells (LSECs) which support macromolecule passage to hepatocytes and prevent fibrosis by keeping hepatic stellate cells (HSCs) quiescent. LSEC specialization is co-determined by transcription factors. The zinc-finger E-box-binding homeobox (Zeb)2 transcription factor is enriched in LSECs. Here, we aimed to elucidate the endothelium-specific role of Zeb2 during maintenance of the liver and in liver fibrosis. METHODS AND RESULTS: To study the role of Zeb2 in liver endothelium we generated EC-specific Zeb2 knock-out (ECKO) mice. Sequencing of liver EC RNA revealed that deficiency of Zeb2 results in prominent expression changes in angiogenesis-related genes. Accordingly, the vascular area was expanded and the presence of pillars inside ECKO liver vessels indicated that this was likely due to increased intussusceptive angiogenesis. LSEC marker expression was not profoundly affected and fenestrations were preserved upon Zeb2 deficiency. However, an increase in continuous EC markers suggested that Zeb2-deficient LSECs are more prone to dedifferentiation, a process called 'capillarization'. Changes in the endothelial expression of ligands that may be involved in HSC quiescence together with significant changes in the expression profile of HSCs showed that Zeb2 regulates LSEC-HSC communication and HSC activation. Accordingly, upon exposure to the hepatotoxin carbon tetrachloride (CCl4), livers of ECKO mice showed increased capillarization, HSC activation, and fibrosis compared to livers from wild-type littermates. The vascular maintenance and anti-fibrotic role of endothelial Zeb2 was confirmed in mice with EC-specific overexpression of Zeb2, as the latter resulted in reduced vascularity and attenuated CCl4-induced liver fibrosis. CONCLUSION: Endothelial Zeb2 preserves liver angioarchitecture and protects against liver fibrosis. Zeb2 and Zeb2-dependent genes in liver ECs may be exploited to design novel therapeutic strategies to attenuate hepatic fibrosis.

Macrophage scavenger receptor 1 mediates lipid-induced inflammation in non-alcoholic fatty liver disease.

BACKGROUND & AIMS: Obesity-associated inflammation is a key player in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). However, the role of macrophage scavenger receptor 1 (MSR1, CD204) remains incompletely understood. METHODS: A total of 170 NAFLD liver biopsies were processed for transcriptomic analysis and correlated with clinicopathological features. Msr1-/- and wild-type mice were subjected to a 16-week high-fat and high-cholesterol diet. Mice and ex vivo human liver slices were treated with a monoclonal antibody against MSR1. Genetic susceptibility was assessed using genome-wide association study data from 1,483 patients with NAFLD and 430,101 participants of the UK Biobank. RESULTS: MSR1 expression was associated with the occurrence of hepatic lipid-laden foamy macrophages and correlated with the degree of steatosis and steatohepatitis in patients with NAFLD. Mice lacking Msr1 were protected against diet-induced metabolic disorder, showing fewer hepatic foamy macrophages, less hepatic inflammation, improved dyslipidaemia and glucose tolerance, and altered hepatic lipid metabolism. Upon induction by saturated fatty acids, MSR1 induced a pro-inflammatory response via the JNK signalling pathway. In vitro blockade of the receptor prevented the accumulation of lipids in primary macrophages which inhibited the switch towards a pro-inflammatory phenotype and the release of cytokines such as TNF-ɑ. Targeting MSR1 using monoclonal antibody therapy in an obesity-associated NAFLD mouse model and human liver slices resulted in the prevention of foamy macrophage formation and inflammation. Moreover, we identified that rs41505344, a polymorphism in the upstream transcriptional region of MSR1, was associated with altered serum triglycerides and aspartate aminotransferase levels in a cohort of over 400,000 patients. CONCLUSIONS: Taken together, our data suggest that MSR1 plays a critical role in lipid-induced inflammation and could thus be a potential therapeutic target for the treatment of NAFLD. LAY SUMMARY: Non-alcoholic fatty liver disease (NAFLD) is a chronic disease primarily caused by excessive consumption of fat and sugar combined with a lack of exercise or a sedentary lifestyle. Herein, we show that the macrophage scavenger receptor MSR1, an innate immune receptor, mediates lipid uptake and accumulation in Kupffer cells, resulting in liver inflammation and thereby promoting the progression of NAFLD in humans and mice.

Laparoscopic versus EUS-guided gastroenterostomy for gastric outlet obstruction: an international multicenter propensity score-matched comparison (with video).

BACKGROUND AND AIMS: In the management of gastric outlet obstruction (GOO), EUS-guided gastroenterostomy (EUS-GE) seems to be safe and more effective than enteral stent placement. However, comparisons with laparoscopic GE (L-GE) are scarce. Our aim was to perform a propensity score-matched comparison between EUS-GE and L-GE. METHODS: An international, multicenter, retrospective analysis was performed of consecutive EUS-GE and L-GE procedures in 3 academic centers (January 2015 to May 2020) using propensity score matching to minimize selection bias. A standard maximum propensity score difference of .1 was applied, also considering underlying disease and oncologic staging. RESULTS: Overall, 77 patients were treated with EUS-GE and 48 patients with L-GE. By means of propensity score matching, 37 patients were allocated to both groups, resulting in 74 (1:1) matched patients. Technical success was achieved in 35 of 37 EUS-GE-treated patients (94.6%) versus 100% in the L-GE group (P = .493). Clinical success, defined as eating without vomiting or GOO Scoring System ≥2, was achieved in 97.1% and 89.2%, respectively (P = .358). Median time to oral intake (1 [interquartile range {IQR}, .3-1.0] vs 3 [IQR, 1.0-5.0] days, P < .001) and median hospital stay (4 [IQR, 2-8] vs 8 [IQR, 5.5-20] days, P < .001) were significantly shorter in the EUS-GE group. Overall (2.7% vs 27.0%, P = .007) and severe (.0% vs 16.2%, P = .025) adverse events were identified more frequently in the L-GE group. CONCLUSIONS: For patients with GOO, EUS-GE and L-GE showed almost identical technical and clinical success. However, reduced time to oral intake, shorter median hospital stay, and lower rate of adverse events suggest that the EUS-guided approach might be preferable.

Comprehensive targeted next-generation sequencing approach in the molecular diagnosis of gastrointestinal stromal tumor.

Mutational analysis guides therapeutic decision making in patients with advanced-stage gastrointestinal stromal tumors (GISTs). We evaluated three targeted next-generation sequencing (NGS) assays, consecutively used over 4 years in our laboratory for mutational analysis of 162 primary GISTs: Agilent GIST MASTR, Illumina TruSight 26 and an in-house developed 96 gene panels. In addition, we investigated the feasibility of a more comprehensive approach by adding targeted RNA sequencing (Archer FusionPlex, 11 genes) in an attempt to reduce the number of Wild Type GISTs. We found KIT or PDGFRA mutations in 149 out of 162 GISTs (92.0%). Challenging KIT exon 11 alterations were initially missed by different assays in seven GISTs and typically represented deletions at the KIT intron 10-exon 11 boundary or large insertions/deletions (>24 base pairs). Comprehensive analysis led to the additional identification of driver alterations in 8/162 GISTs (4.9%): apart from BRAF and SDHA mutations (one case each), we found five GISTs harboring somatic neurofibromatosis type 1 (NF1) alterations (3.1%) and one case with an in-frame TRIM4-BRAF fusion not reported in GIST before. Eventually, no driver alteration was found in two out of 162 GISTs (1.2%) and three samples (1.9%) failed analysis. Our study shows that a comprehensive targeted NGS approach is feasible for routine mutational analysis of GIST, thereby substantially reducing the number of Wild Type GISTs, and highlights the need to optimize assays for challenging KIT exon 11 alterations.

Predictors of survival after surgery with curative intent for perihilar cholangiocarcinoma.

BACKGROUND: Several clinicopathological predictors of survival after curative surgery for perihilar cholangiocarcinoma (pCCA) have been identified; however, conflicting reports remain. The aim was to analyse clinical and oncological outcomes after curative resection of pCCA and to determine prognostic factors. METHODS: Eighty-eight consecutive patients with pCCA underwent surgery with curative intent between 1998 and 2017. Survival curves were estimated using the Kaplan-Meier method and compared using the log-rank test. Twenty-one prognostic factors were evaluated using multivariate Cox regression models. RESULTS: Postoperative complications were observed in 73 (83%) patients of which 41 (47%) were severe complications (therapy-oriented severity grading system (TOSGS) grade > 2), including a 90-day mortality of 9% (n = 8). Overall survival (OS) and disease-free survival (DFS) rates at 5 and 10 years after surgery were 33% and 19%, and 37% and 30%, respectively. Independent predictors of OS were locoregional lymph node metastasis (LNM) (risk ratio (RR) 2.12, confidence interval (CI) 1.19-3.81, p = 0.011), patient American Society of Anesthesiologists (ASA) physical status classification system > 2 (RR 2.10, CI 1.03-4.26, p = 0.043), and depth of tumour penetration (pT) > 2 (RR 2.58, CI 1.03-6.30, p = 0.043). The presence of locoregional LNM (RR 2.95, CI 1.51-5.90, p = 0.002) and caudate lobe resection (RR 2.19, CI 1.01-5.14, p = 0.048) were found as independent predictors of DFS. CONCLUSIONS: Curative surgery for pCCA carries high risks with poor long-term survival. Locoregional LNM was the only predictor for both OS and DFS.