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Obesity and obesity-related disorders are a global epidemic affecting over 10% of the world's population. Treatment of these diseases has become increasingly challenging and expensive. The most effective and durable treatment for Class III obesity (body mass index ≥35 kg/m) is bariatric surgery, namely, Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy. These procedures are associated with increased circulating bile acids, molecules that not only facilitate intestinal fat absorption but are also potent hormones regulating numerous metabolic pathways. We recently reported on a novel surgical procedure in mice, termed distal gallbladder bile diversion to the ileum (GB-IL), that emulates the altered bile flow after RYGB without other manipulations of gastrointestinal anatomy. GB-IL improves oral glucose tolerance in mice made obese with high-fat diet. This is accompanied by fat malabsorption and weight loss, which complicates studying the role of elevated circulating bile acids in metabolic control. A less aggressive surgery in which the gallbladder bile is diverted to the proximal ileum, termed GB-IL, also improves glucose control but is not accompanied by fat malabsorption. To better understand the differential effects achieved by these bile diversion procedures, an untargeted ultraperformance liquid chromatography-ion mobility-mass spectrometry (UPLC-IM-MS) method was optimized for fecal samples derived from mice that have undergone bile diversion surgery. Utilizing the UPLC-IM-MS method, we were able to identify dysregulation of bile acids, short-chain fatty acids, and cholesterol derivatives that contribute to the differential metabolism resulting from these surgeries.
BACKGROUND - The impact of re-resection of a positive intraoperative bile duct margin on clinical outcomes for resectable hilar cholangiocarcinoma (HCCA) remains controversial. We sought to define the impact of re-resection of an initially positive frozen-section bile duct margin on outcomes of patients undergoing surgery for HCCA.
METHODS - Patients who underwent curative-intent resection for HCCA between 2000 and 2014 were identified at 10 hepatobiliary centers. Short- and long-term outcomes were analyzed among patients stratified by margin status.
RESULTS - Among 215 (83.7%) patients who underwent frozen-section evaluation of the bile duct, 80 (37.2%) patients had a positive (R1) ductal margin, 58 (72.5%) underwent re-resection, and 29 ultimately had a secondary negative margin (secondary R0). There was no difference in morbidity, 30-day mortality, and length of stay among patients who had primary R0, secondary R0, and R1 resection (all p > 0.10). Median and 5-year survival were 22.3 months and 23.3%, respectively, among patients who had a primary R0 resection compared with 18.5 months and 7.9%, respectively, for patients with an R1 resection (p = 0.08). In contrast, among patients who had a secondary R0 margin with re-resection of the bile duct margin, median and 5-year survival were 30.6 months and 44.3%, respectively, which was comparable to patients with a primary R0 margin (p = 0.804). On multivariable analysis, R1 margin resection was associated with decreased survival (R1: hazard ratio [HR] 1.3, 95% confidence interval [CI] 1.0-1.7; p = 0.027), but secondary R0 resection was associated with comparable long-term outcomes as primary R0 resection (HR 0.9, 95% CI 0.4-2.3; p = 0.829).
CONCLUSIONS - Additional resection of a positive frozen-section ductal margin to achieve R0 resection was associated with improved long-term outcomes following curative-intent resection of HCCA.
OBJECTIVE - To investigate the influence of type of surgery (transplant vs resection) on overall survival (OS) in patients with hilar cholangiocarcinoma (H-CCA).
BACKGROUND - Outcomes after resection for H-CCA are poor, yet transplantation is currently only reserved for well-selected patients with unresectable disease.
METHODS - All patients with H-CCA who underwent resection from 2000 to 2015 at 10 institutions were included. Three institutions additionally had active H-CCA transplant protocols with similar selection criteria over similar time periods.
RESULTS - Of 304 patients with suspected H-CCA, 234 underwent attempted resection and 70 were enrolled in a transplant protocol. Excluding incomplete/R2 resections (n = 43), patients who were enrolled, but did not undergo transplant (n = 24), and transplants without confirmed H-CCA diagnoses (n = 5), 191 patients underwent curative-intent resection and 41 curative-intent transplant. Compared with resection, transplant patients were younger (52 vs 65 years; P < 0.001), and more frequently had primary sclerosing cholangitis (PSC; 61% vs 2%; P < 0.001) and received chemotherapy and/or radiation (98% vs 57%; P < 0.001). Groups were otherwise similar in demographics and comorbidities. Patients who underwent transplant for confirmed H-CCA diagnosis had improved OS compared with resection (3-year: 72% vs 33%; 5-year: 64% vs 18%; P < 0.001). Among patients who underwent resection for tumors <3 cm with lymph-node negative disease, and excluding PSC patients, transplant was still associated with improved OS (3-year: 54% vs 44%; 5-year: 54% vs 29%; P = 0.03). Transplant remained associated with improved survival on intention-to-treat analysis, even after accounting for tumor size, lymph node status, and PSC (P = 0.049).
CONCLUSIONS - Resection for hilar cholangiocarcinoma that meets criteria for transplantation (<3 cm, lymph-node negative disease) is associated with substantially decreased survival compared to transplant for the same criteria with unresectable disease. Prospective trials are needed and justified.
BACKGROUND - Coffee consumption has been reported to be inversely associated with hepatocellular carcinoma (HCC), the most common type of liver cancer. Caffeine has chemopreventive properties, but whether caffeine is responsible for the coffee-HCC association is not well studied. In addition, few studies have examined the relationship by sex, and no studies have examined whether there is an association between coffee and intrahepatic cholangiocarcinoma (ICC), the second most common type of liver cancer.
METHODS - In the Liver Cancer Pooling Project, a consortium of U.S.-based cohort studies, data from 1,212,893 individuals (HCC, n = 860; ICC, n = 260) in nine cohorts were pooled. Multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) were estimated using proportional hazards regression.
RESULTS - Higher coffee consumption was associated with lower risk of HCC (HR>3 cups/day vs. non-drinker, 0.73; 95% CI, 0.53-0.99; Ptrend cups/day = <0.0001). More notable reduced risk was seen among women than men (Pinteraction = 0.07). Women who consumed more than three cups of coffee per day were at a 54% lower risk of HCC (HR, 0.46; 95% CI, 0.26-0.81), whereas men had more modest reduced risk of HCC (HR, 0.93; 95% CI, 0.63-1.37). The associations were stronger for caffeinated coffee (HR>3 cups/day vs. non-drinker, 0.71; 95% CI, 0.50-1.01) than decaffeinated coffee (HR, 0.92; 95% CI, 0.55-1.54). There was no association between coffee consumption and ICC.
CONCLUSIONS - These findings suggest that, in a U.S. population, coffee consumption is associated with reduced risk of HCC.
IMPACT - Further research into specific coffee compounds and mechanisms that may account for these associations is needed.
©2015 American Association for Cancer Research.
Glycine-N-methyltransferase (GNMT) is essential to preserve liver homeostasis. Cirrhotic patients show low expression of GNMT that is absent in hepatocellular carcinoma (HCC) samples. Accordingly, GNMT deficiency in mice leads to steatohepatitis, fibrosis, cirrhosis, and HCC. Lack of GNMT triggers NK cell activation in GNMT(-/-) mice and depletion of TRAIL significantly attenuates acute liver injury and inflammation in these animals. Chronic inflammation leads to fibrogenesis, further contributing to the progression of chronic liver injury regardless of the etiology. The aim of our study is to elucidate the implication of TRAIL-producing NK cells in the progression of chronic liver injury and fibrogenesis. For this we generated double TRAIL(-/-)/GNMT(-/-) mice in which we found that TRAIL deficiency efficiently protected the liver against chronic liver injury and fibrogenesis in the context of GNMT deficiency. Next, to better delineate the implication of TRAIL-producing NK cells during fibrogenesis we performed bile duct ligation (BDL) to GNMT(-/-) and TRAIL(-/-)/GNMT(-/-) mice. In GNMT(-/-) mice, exacerbated fibrogenic response after BDL concurred with NK1.1(+) cell activation. Importantly, specific inhibition of TRAIL-producing NK cells efficiently protected GNMT(-/-) mice from BDL-induced liver injury and fibrogenesis. Finally, TRAIL(-/-)/GNMT(-/-) mice showed significantly less fibrosis after BDL than GNMT(-/-) mice further underlining the relevance of the TRAIL/DR5 axis in mediating liver injury and fibrogenesis in GNMT(-/-) mice. Finally, in vivo silencing of DR5 efficiently protected GNMT(-/-) mice from BDL-liver injury and fibrogenesis, overall underscoring the key role of the TRAIL/DR5 axis in promoting fibrogenesis in the context of absence of GNMT. Overall, our work demonstrates that TRAIL-producing NK cells actively contribute to liver injury and further fibrogenesis in the pathological context of GNMT deficiency, a molecular scenario characteristic of chronic human liver disease.
UNLABELLED - Shotgun proteomics is a powerful analytic method to characterize complex protein mixtures in combination with multidimensional liquid chromatography-tandem mass spectrometry (LC-MS/MS). We used this platform for proteomic characterization of apoptotic bodies in an effort to define the complex protein mixtures found in primary cultures of human intrahepatic biliary epithelial cells (HiBEC), human renal proximal tubular epithelial cells, human bronchial epithelial cells, isolated intrahepatic biliary epithelial cells from explanted primary biliary cirrhosis (PBC), and control liver using a total of 24 individual samples. Further, as additional controls and for purposes of comparison, proteomic signatures were also obtained from intact cells and apoptotic bodies. The data obtained from LC-MS/MS, combined with database searches and protein assembly algorithms, allowed us to address significant differences in protein spectral counts and identify unique pathways that may be a component of the induction of the signature inflammatory cytokine response against BECs, including the Notch signaling pathway, interleukin (IL)8, IL6, CXCR2, and integrin signaling. Indeed, there are 11 proteins that localize specifically to apoptotic bodies of HiBEC and eight proteins that were specifically absent in HiBEC apoptotic bodies.
CONCLUSION - Proteomic analysis of BECs from PBC liver compared to normal liver are significantly different, suggesting that an immunological attack affects the repertoire of proteins expressed and that such cells should be thought of as living in an environment undergoing continuous selection secondary to an innate and adaptive immune response, reflecting an almost "Darwinian" bias.
© 2014 by the American Association for the Study of Liver Diseases.
The papanicolaou society of cytopathology (PSC) has developed a set of guidelines for pancreatobiliary cytology including indications for endoscopic ultrasound (EUS) guided fine-needle aspiration (FNA) biopsy, techniques of EUS-FNA, terminology and nomenclature for pancreatobiliary cytology, ancillary testing, and postprocedure management. All documents are based on the expertise of the authors, a review of the literature, discussions of the draft document at several national and international meetings over an 18 month period and synthesis of online comments of the draft document on the PSC web site [www.papsociety.org]. This document selectively presents the results of these discussions and focuses on the follow-up and treatment options for patients after procedures performed for obtaining cytology samples for the evaluation of biliary strictures and solid and cystic masses in the pancreas. These recommendations follow the six-tiered terminology and nomenclature scheme proposed by Committee III.
Copyright © 2014 Wiley Periodicals, Inc.
The potential for intrahepatic bile duct (IHBD) regeneration in patients with bile duct insufficiency diseases is poorly understood. Notch signaling and Hnf6 have each been shown to be important for the morphogenesis of IHBDs in mice. One congenital pediatric liver disease characterized by reduced numbers of IHBDs, Alagille syndrome, is associated with mutations in Notch signaling components. Therefore, we investigated whether liver cell plasticity could contribute to IHBD regeneration in mice with disruptions in Notch signaling and Hnf6. We studied a mouse model of bile duct insufficiency with liver epithelial cell-specific deficiencies in Hnf6 and Rbpj, a mediator of canonical Notch signaling. Albumin-Cre Hnf6(flox/flox)Rbpj(flox/flox) mice initially developed no peripheral bile ducts. The evolving postnatal liver phenotype was analyzed using IHBD resin casting, immunostaining, and serum chemistry. With age, Albumin-Cre Hnf6(flox/flox)Rbpj(flox/flox) mice mounted a ductular reaction extending through the hepatic tissue and then regenerated communicating peripheral IHBD branches. Rbpj and Hnf6 were determined to remain absent from biliary epithelial cells constituting the ductular reaction and the regenerated peripheral IHBDs. We report the expression of Sox9, a marker of biliary epithelial cells, in cells expressing hepatocyte markers. Tissue analysis indicates that reactive ductules did not arise directly from preexisting hilar IHBDs. We conclude that liver cell plasticity is competent for regeneration of IHBDs independent of Notch signaling via Rbpj and Hnf6.
Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
The indications for duct-to-duct (DD) biliary reconstruction in living donor liver transplantation (LDLT) for small children are still controversial. In this study, the feasibility of DD biliary reconstruction versus Roux-en-Y (RY) biliary reconstruction was investigated in terms of long-term outcomes. Fifty-six children who consecutively underwent LDLT with a weight less than or equal to 10.0 kg were enrolled. Biliary reconstruction was performed in a DD fashion for 20 patients and in an RY fashion for 36 patients. During a minimum follow-up of 2 years, the incidence of biliary strictures was 5.0% in the DD group and 11.1% in the RY group. Cholangitis during the posttransplant period was observed in the RY group only. There were no deaths related to biliary problems. This study shows that DD reconstruction in LDLT for small children (weighing 10.0 kg or less) is a feasible option for biliary reconstruction.
© 2014 American Association for the Study of Liver Diseases.
BACKGROUND & AIMS - Metaplasias often have characteristics of developmentally related tissues. Pancreatic metaplastic ducts are usually associated with pancreatitis and pancreatic ductal adenocarcinoma. The tuft cell is a chemosensory cell that responds to signals in the extracellular environment via effector molecules. Commonly found in the biliary tract, tuft cells are absent from normal murine pancreas. Using the aberrant appearance of tuft cells as an indicator, we tested if pancreatic metaplasia represents transdifferentiation to a biliary phenotype and what effect this has on pancreatic tumorigenesis.
METHODS - We analyzed pancreatic tissue and tumors that developed in mice that express an activated form of Kras (Kras(LSL-G12D/+);Ptf1a(Cre/+) mice). Normal bile duct, pancreatic duct, and tumor-associated metaplasias from the mice were analyzed for tuft cell and biliary progenitor markers, including SOX17, a transcription factor that regulates biliary development. We also analyzed pancreatic tissues from mice expressing transgenic SOX17 alone (ROSA(tTa/+);Ptf1(CreERTM/+);tetO-SOX17) or along with activated Kras (ROSAtT(a/+);Ptf1a(CreERTM/+);tetO-SOX17;Kras(LSL-G12D;+)).
RESULTS - Tuft cells were frequently found in areas of pancreatic metaplasia, decreased throughout tumor progression, and absent from invasive tumors. Analysis of the pancreatobiliary ductal systems of mice revealed tuft cells in the biliary tract but not the normal pancreatic duct. Analysis for biliary markers revealed expression of SOX17 in pancreatic metaplasia and tumors. Pancreas-specific overexpression of SOX17 led to ductal metaplasia along with inflammation and collagen deposition. Mice that overexpressed SOX17 along with Kras(G12D) had a greater degree of transformed tissue compared with mice expressing only Kras(G12D). Immunofluorescence analysis of human pancreatic tissue arrays revealed the presence of tuft cells in metaplasia and early-stage tumors, along with SOX17 expression, consistent with a biliary phenotype.
CONCLUSIONS - Expression of Kras(G12D) and SOX17 in mice induces development of metaplasias with a biliary phenotype containing tuft cells. Tuft cells express a number of tumorigenic factors that can alter the microenvironment. Expression of SOX17 induces pancreatitis and promotes Kras(G12D)-induced tumorigenesis in mice.
Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.