Upregulation of the ERRγ-VDAC1 axis underlies the molecular pathogenesis of pancreatitis.

Emerging evidence suggest that transcription factors play multiple roles in the development of pancreatitis, a necroinflammatory condition lacking specific therapy. Estrogen-related receptor γ (ERRγ), a pleiotropic transcription factor, has been reported to play a vital role in pancreatic acinar cell (PAC) homeostasis. However, the role of ERRγ in PAC dysfunction remains hitherto unknown. Here, we demonstrated in both mice models and human cohorts that pancreatitis is associated with an increase in ERRγ gene expression via activation of STAT3. Acinar-specific ERRγ haploinsufficiency or pharmacological inhibition of ERRγ significantly impaired the progression of pancreatitis both in vitro and in vivo. Using systematic transcriptomic analysis, we identified that voltage-dependent anion channel 1 (VDAC1) acts as a molecular mediator of ERRγ. Mechanistically, we showed that induction of ERRγ in cultured acinar cells and mouse pancreata enhanced VDAC1 expression by directly binding to specific site of the Vdac1 gene promoter and resulted in VDAC1 oligomerization. Notably, VDAC1, whose expression and oligomerization were dependent on ERRγ, modulates mitochondrial Ca2+ and ROS levels. Inhibition of the ERRγ-VDAC1 axis could alleviate mitochondrial Ca2+ accumulation, ROS formation and inhibit progression of pancreatitis. Using two different mouse models of pancreatitis, we showed that pharmacological blockade of ERRγ-VDAC1 pathway has therapeutic benefits in mitigating progression of pancreatitis. Likewise, using PRSS1R122H-Tg mice to mimic human hereditary pancreatitis, we demonstrated that ERRγ inhibitor also alleviated pancreatitis. Our findings highlight the importance of ERRγ in pancreatitis progression and suggests its therapeutic intervention for prevention and treatment of pancreatitis.

Dynamic Alterations to Hepatic MicroRNA-29a in Response to Long-Term High-Fat Diet and EtOH Feeding.

MicroRNA-29a (miR-29a) is a well characterized fibro-inflammatory molecule and its aberrant expression is linked to a variety of pathological liver conditions. The long-term effects of a high-fat diet (HFD) in combination with different levels of EtOH consumption on miR-29a expression and liver pathobiology are unknown. Mice at 8 weeks of age were divided into five groups (calorie-matched diet plus water (CMD) as a control group, HFD plus water (HFD) as a liver disease group, HFD plus 2% EtOH (HFD + 2% E), HFD + 10% E, and HFD + 20% E as intervention groups) and fed for 4, 13, 26, or 39 weeks. At each time point, analyses were performed for liver weight/body weight (BW) ratio, AST/ALT ratio, as well as liver histology assessments, which included inflammation, estimated fat deposition, lipid area, and fibrosis. Hepatic miR-29a was measured and correlations with phenotypic traits were determined. Four-week feeding produced no differences between the groups on all collected phenotypic traits or miR-29a expression, while significant effects were observed after 13 weeks, with EtOH concentration-specific induction of miR-29a. A turning point for most of the collected traits was apparent at 26 weeks, and miR-29a was significantly down-regulated with increasing liver injury. Overall, miR-29a up-regulation was associated with a lower liver/BW ratio, fat deposition, inflammation, and fibrosis, suggesting a protective role of miR-29a against liver disease progression. A HFD plus increasing concentrations of EtOH produces progressive adverse effects on the liver, with no evidence of beneficial effects of low-dose EtOH consumption. Moreover, miR-29a up-regulation is associated with less severe liver injury.

The Apelin-Apelin Receptor Axis Triggers Cholangiocyte Proliferation and Liver Fibrosis During Mouse Models of Cholestasis.

BACKGROUND AND AIMS: Apelin (APLN) is the endogenous ligand of its G protein-coupled receptor, apelin receptor (APJ). APLN serum levels are increased in human liver diseases. We evaluated whether the APLN-APJ axis regulates ductular reaction and liver fibrosis during cholestasis. APPROACH AND RESULTS: We measured the expression of APLN and APJ and serum APLN levels in human primary sclerosing cholangitis (PSC) samples. Following bile duct ligation (BDL) or sham surgery, male wild-type (WT) mice were treated with ML221 (APJ antagonist) or saline for 1 week. WT and APLN-/- mice underwent BDL or sham surgery for 1 week. Multidrug resistance gene 2 knockout (Mdr2-/- ) mice were treated with ML221 for 1 week. APLN levels were measured in serum and cholangiocyte supernatants, and cholangiocyte proliferation/senescence and liver inflammation, fibrosis, and angiogenesis were measured in liver tissues. The regulatory mechanisms of APLN-APJ in (1) biliary damage and liver fibrosis were examined in human intrahepatic biliary epithelial cells (HIBEpiCs) treated with APLN and (2) hepatic stellate cell (HSC) activation in APLN-treated human HSC lines (HHSteCs). APLN serum levels and biliary expression of APLN and APJ increased in PSC samples. APLN levels were higher in serum and cholangiocyte supernatants from BDL and Mdr2-/- mice. ML221 treatment or APLN-/- reduced BDL-induced and Mdr2-/- -induced cholangiocyte proliferation/senescence, liver inflammation, fibrosis, and angiogenesis. In vitro, APLN induced HIBEpiC proliferation, increased nicotinamide adenine dinucleotide phosphate oxidase 4 (Nox4) expression, reactive oxygen species (ROS) generation, and extracellular signal-regulated kinase (ERK) phosphorylation. Pretreatment of HIBEpiCs with ML221, diphenyleneiodonium chloride (Nox4 inhibitor), N-acetyl-cysteine (NAC, ROS inhibitor), or PD98059 (ERK inhibitor) reduced APLN-induced cholangiocyte proliferation. Activation of HHSteCs was induced by APLN but reduced by NAC. CONCLUSIONS: The APLN-APJ axis induces cholangiocyte proliferation through Nox4/ROS/ERK-dependent signaling and HSC activation through intracellular ROS. Modulation of the APLN-APJ axis may be important for managing cholangiopathies.

Consensus recommendations for histological criteria of autoimmune hepatitis from the International AIH Pathology Group: Results of a workshop on AIH histology hosted by the European Reference Network on Hepatological Diseases and the European Society of Pathology: Results of a workshop on AIH histology hosted by the European Reference Network on Hepatological Diseases and the European Society of Pathology.

BACKGROUND & AIMS: Diagnostic histological criteria for autoimmune hepatitis (AIH) have not been clearly established. Previously published criteria focused mainly on chronic AIH, in which inflammatory changes mainly occur in portal/periportal regions and may not be applicable to acute presentation of AIH, in which inflammatory changes are typically predominantly lobular in location. International consensus criteria for the diagnosis and assessment of disease severity in both acute and chronic AIH are thus urgently needed. METHODS: Seventeen expert liver pathologists convened at an international workshop and subsequently used a modified Delphi panel approach to establish consensus criteria for the histopathological diagnosis of AIH. RESULTS: The consensus view is that liver biopsy should remain standard for diagnosing AIH. AIH is considered likely, if there is a predominantly portal lymphoplasmacytic hepatitis with more than mild interface activity and/or more than mild lobular hepatitis in the absence of histological features suggestive of another liver disease. AIH is also considered likely if there is predominantly lobular hepatitis with or without centrilobular necroinflammation and at least one of the following features: portal lymphoplasmacytic hepatitis, interface hepatitis or portal-based fibrosis, in the absence of histological features suggestive of another liver disease. Emperipolesis and hepatocellular rosettes are not regarded as being specific for AIH. CONCLUSIONS: The criteria proposed in this consensus statement provide a uniform approach to the histological diagnosis of AIH, which is relevant for patients with an acute as well as a chronic presentation and to more accurately reflect the current understanding of liver pathology in AIH.

A High Serum Level of Taurocholic Acid Is Correlated With the Severity and Resolution of Drug-induced Liver Injury.

BACKGROUND & AIMS: Alterations in the serum levels of bile acids are associated with drug-induced liver injury (DILI). We investigated the association between serum levels of bile acids and the severity and outcome of DILI, along with the potential role of variants in the ATP binding cassette subfamily B member 11 (ABCB11) gene and expression of its product, ABCB11 (also called BSEP). METHODS: We performed this prospective study of 95 patients (median age, 53 years; 73.7% female) with DILI from August 2018 through August 2019. Patients were matched for age, gender, and body mass index with healthy individuals (n = 100; healthy controls) and patients with chronic hepatitis B (n = 105; CHB controls). We collected demographic and biochemical data at baseline and 1 week, 1 month, 3 months, and 6 months after DILI onset and at the time of biochemical recovery, liver failure or liver transplantation. Serum levels of bile acids were measured using high-performance liquid-chromatography tandem mass-spectrometry. All 27 exons of ABCB11 were sequenced and expression of BSEP was analyzed by immunohistochemistry in liver biopsy specimens. RESULTS: Levels of 30 of the 37 bile acids analyzed differed significantly between patients with DILI and healthy controls. Changes in levels of taurocholic acid (TCA), glycocholic acid, taurochenodeoxycholate, and glycochenodeoxycholate associated with the increased levels of bilirubin and greater severity of DILI, and were also associated with CHB. Cox regression analysis showed that only change in the levels of TCA independently associated with biochemical resolution of DILI. Combination of TCA level (≥ 1955.41 nmol/L), patient age, and DILI severity was associated with abnormal blood biochemistry at 6 months after DILI onset (area under the curve, 0.81; 95% confidence interval, 0.71-0.88; sensitivity, 0.69; specificity, 0.81). ABCB11 missense variants were not associated with differences in the serum bile acid profiles, DILI severity, or clinical resolution. However, lower levels of BSEP in bile canaliculi in liver biopsies were associated with altered serum levels of bile acids. CONCLUSIONS: In this prospective study performed in Chinese patients, we found that the serum levels of TCA were associated with the severity and clinical resolution of DILI. Reduced protein expression of BSEP in liver tissue, rather than variants of the ABCB11 gene were associated with altered serum levels of bile acids.

Vitamin E Improves Transplant-Free Survival and Hepatic Decompensation Among Patients With Nonalcoholic Steatohepatitis and Advanced Fibrosis.

Vitamin E improves liver histology in adults with nonalcoholic steatohepatitis (NASH) but not diabetes, but its impact on long-term patient outcomes is unknown. We evaluated whether vitamin E treatment improves clinical outcomes of NASH patients with bridging fibrosis or cirrhosis. Two hundred and thirty-six patients with biopsy-proven NASH and bridging fibrosis or cirrhosis seen at Indiana University Medical Center between October 2004 and January 2016 were included. Ninety of them took 800 international units/day of vitamin E for ≥2 years (vitamin E users) and were propensity-matched to 90 adults who did not take vitamin E (controls) after adjusting for fibrosis severity, age, gender, body mass index, comorbidities and their treatment, low-density lipoprotein cholesterol, liver biochemistries, and length of follow-up on vitamin E. Covariate-adjusted Cox and competing risk regression models were assessed to evaluate the association between vitamin E treatment and patient outcomes. The median follow-up was 5.62 (interquartile range [IQR], 4.3-7.5) and 5.6 (IQR, 4-6.9) years for vitamin E users and controls, respectively. Vitamin E users had higher adjusted transplant-free survival (78% versus 49%, P < 0.01) and lower rates of hepatic decompensation (37% versus 62%, P = 0.04) than controls. After controlling for severity of fibrosis, calendar year of patient enrollment, and other potential confounders, vitamin E treatment decreased the risk of death or transplant (adjusted hazard ratio, 0.30; 95% confidence interval [CI], 0.12-0.74; P < 0.01) and hepatic decompensation (adjusted sub-HR, 0.52; 95% CI, 0.28-0.96; P = 0.036). These benefits were evident in both those with diabetes and those without diabetes. Adjusted 10-year cumulative probabilities of hepatocellular carcinoma, vascular events, and nonhepatic cancers were not different between vitamin E-exposed patients and controls. Conclusion: Vitamin E use was associated with improved clinical outcomes in patients with NASH and bridging fibrosis or cirrhosis.

Sestrin 3 Protects Against Diet-Induced Nonalcoholic Steatohepatitis in Mice Through Suppression of Transforming Growth Factor ß Signal Transduction.

Sestrin 3 (Sesn3) belongs to the three-member sestrin protein family. Sestrins have been implicated in antioxidative stress, adenosine monophosphate-activated protein kinase and mammalian target of rapamycin signal transduction, and metabolic homeostasis. However, the role of Sesn3 in the development of nonalcoholic steatohepatitis (NASH) has not been previously studied. In this work, we generated Sesn3 whole-body knockout and liver-specific transgenic mice to investigate the hepatic function of Sesn3 in diet-induced NASH. With only 4 weeks of dietary treatment, Sesn3 knockout mice developed severe NASH phenotype as characterized by hepatic steatosis, inflammation, and fibrosis. Strikingly, after 8-week feeding with a NASH-inducing diet, Sesn3 transgenic mice were largely protected against NASH development. Transcriptomic analysis revealed that multiple extracellular matrix-related processes were up-regulated, including transforming growth factor ß (TGF-ß) signaling and collagen production. Further biochemical and cell biological analyses have illustrated a critical control of the TGF-ß-mothers against decapentaplegic homolog (Smad) pathway by Sesn3 at the TGF-ß receptor and Smad3 levels. First, Sesn3 inhibits the TGF-ß receptor through an interaction with Smad7; second, Sesn3 directly inhibits the Smad3 function through protein-protein interaction and cytosolic retention. Conclusion: Sesn3 is a critical regulator of the extracellular matrix and hepatic fibrosis by suppression of TGF-ß-Smad3 signaling.

Modulation of the Tryptophan Hydroxylase 1/Monoamine Oxidase-A/5-Hydroxytryptamine/5-Hydroxytryptamine Receptor 2A/2B/2C Axis Regulates Biliary Proliferation and Liver Fibrosis During Cholestasis.

BACKGROUND AND AIMS: Serotonin (5HT) is a neuroendocrine hormone synthetized in the central nervous system (CNS) as well as enterochromaffin cells of the gastrointestinal tract. Tryptophan hydroxylase (TPH1) and monoamine oxidase (MAO-A) are the key enzymes for the synthesis and catabolism of 5HT, respectively. Previous studies demonstrated that 5-hydroxytryptamine receptor (5HTR)1A/1B receptor agonists inhibit biliary hyperplasia in bile-duct ligated (BDL) rats, whereas 5HTR2B receptor antagonists attenuate liver fibrosis (LF) in mice. Our aim was to evaluate the role of 5HTR2A/2B/2C agonists/antagonists in cholestatic models. APPROACH AND RESULTS: While in vivo studies were performed in BDL rats and the multidrug resistance gene 2 knockout (Mdr2-/- ) mouse model of PSC, in vitro studies were performed in cell lines of cholangiocytes and hepatic stellate cells (HSCs). 5HTR2A/2B/2C and MAO-A/TPH1 are expressed in cholangiocytes and HSCs from BDL rats and Mdr2-/- - mice. Ductular reaction, LF, as well as the mRNA expression of proinflammatory genes increased in normal, BDL rats, and Mdr2-/- - mice following treatment 5HTR2A/2B/2C agonists, but decreased when BDL rats and Mdr2-/- mice were treated with 5HTR2A/2B/2C antagonists compared to BDL rats and Mdr2-/- mice, respectively. 5HT levels increase in Mdr2-/- mice and in PSC human patients compared to their controls and decrease in serum of Mdr2-/- mice treated with 5HTR2A/2B/2C antagonists compared to untreated Mdr2-/- mice. In vitro, cell lines of murine cholangiocytes and human HSCs express 5HTR2A/2B/2C and MAO-A/TPH1; treatment of these cell lines with 5HTR2A/2B/2C antagonists or TPH1 inhibitor decreased 5HT levels as well as expression of fibrosis and inflammation genes compared to controls. CONCLUSIONS: Modulation of the TPH1/MAO-A/5HT/5HTR2A/2B/2C axis may represent a therapeutic approach for management of cholangiopathies, including PSC.

Regression of Hepatic Fibrosis and Evolution of Cirrhosis: A Concise Review.

Fibrosis is not a unidirectional, linear process, but a dynamic one resulting from an interplay of fibrogenesis and fibrolysis depending on the extent and severity of a biologic insult, or lack thereof. Regression of fibrosis has been documented best in patients treated with phlebotomies for hemochromatosis, and after successful suppression and eradication of chronic hepatitis B and C infections. This evidence mandates a reconsideration of the term "cirrhosis," which implies an inevitable progression towards liver failure. Furthermore, it also necessitates a staging system that acknowledges the bidirectional nature of evolution of fibrosis, and has the ability to predict if the disease process is progressing or regressing. The Beijing classification attempts to fill this gap in contemporary practice. It is based on microscopic features termed "the hepatic repair complex," defined originally by Wanless and colleagues. The elements of the hepatic repair complex represent the 3 processes of fragmentation and regression of scar, vascular remodeling (resolution), and parenchymal regeneration. However, regression of fibrosis does not imply resolution of cirrhosis, which is more than just a stage of fibrosis. So far, there is little to no evidence to suggest that large regions of parenchymal extinction can be repopulated by regenerating hepatocytes. Similarly, the vascular lesions of cirrhosis persist, and there is no evidence of complete return to normal microcirculation in cirrhotic livers. In addition, the risk of hepatocellular carcinoma is higher compared with the general population and these patients need continued screening and surveillance.

Role of the Surgical Pathologist in Diagnosis of Drug-induced Liver Injury: Recognizing Specific Patterns of Drug Injury.

Eighteen histologic patterns of drug-induced liver injury (DILI) are described, most of which are also seen in other commonly occurring acute and chronic liver diseases. However, certain patterns such as sinusoidal obstruction syndrome/veno-occlusive disease, "bland" cholestasis and cholestatic hepatitis are more often caused by drugs than other competing etiologies. Amiodarone, acetaminophen, anabolic androgenic steroids and estrogens, result in histologic patterns that are virtually diagnostic of the respective drug. Recognition of a DILI or drug specific injury pattern enables the clinician to focus on eliciting an appropriate history to identify the offending agent, which may otherwise be rare and not immediately apparent. Although drugs can mimic any and every liver disease, the mimicry is often imperfect. Unusual features that do not completely fit the clinicopathologic paradigm of the mimicked liver disease are clues to diagnosis of DILI. When mimicking a liver disease, drugs tend to hasten or accelerate the natural progression of the disease. Novel immunomodulatory drugs for inflammatory disorders and cancer may cause unintended effects on the immune system, resulting in immune-related side effects. The role of the pathologist in diagnosis of DILI is to recognize known patterns of DILI, and either confirm a diagnosis when clinically suspected, or alert the clinician to the possibility of DILI when it is not suspected. The latter is particularly vital in contemporary practice, which is witnessing an accelerated pace of drug development, and a surge in consumption of nutritional supplements and herbal compounds by an increasingly health conscious society.

A Comparative Study of 22G versus 19G Needles for EUS-Guided Biopsies for Parenchymal Liver Disease: Are Thinner Needles Better?

BACKGROUND AND AIMS: Data on comparative efficacy of various available endoscopic ultrasound-guided liver biopsy (EUS-LB) needles are limited. We sought to compare the performance of a novel Franseen-tip 22G fine-needle biopsy (FNB) device to that of 19G needle platforms for liver parenchyma. METHODS: Consecutive patients referred for EUS and suspected to have hepatic parenchymal disease underwent EUS-LB using different EUS needles and were included in this retrospective study. Two blinded expert liver pathologists independently reviewed and reported on: total number of tissue fragments, length of longest fragment, number of complete and incomplete portal tracts (CPT and IPT), and specimen adequacy. RESULTS: A 22G Franseen-tip needle (A) was used in 30 patients; 19G Tru-Cut needle (B) in 50 patients; 19G reverse beveled non-Tru-Cut needle (C) in 27 patients; and a 19G flexible non-Tru-Cut needle (D) in 28 patients. In the order of needles, A, B, C and D, > 10 tissue fragments were obtained in 100%, 6%, 82%, and 96% samples, the mean number of CPTs was 6.9; 3.0; 7.3; and 16.9, length of longest fragment was 3.8, 4. 7, 3.9, and 8.4 mm, and specimen adequacy was 66.7%, 46%, 82.1%, and 81.5%, respectively. A positive correlation was obtained between number of CPTs and length of longest fragment in samples accrued by 19G needles. CONCLUSION: EUS-LB specimens using 22G Franseen-tip needle appear highly fragmented, leading to inferior specimen adequacy compared to 19G non-Tru-Cut needles. We also report on using length of longest fragment as an additional criterion for specimen adequacy as it positively correlates with number of CPTs standard.

Hepatic Histopathology Among Excessive Drinkers Without Advanced Liver Disease.

AIMS: Alcohol-associated liver disease represents a spectrum of histopathological changes from steatosis to advanced fibrosis and cirrhosis. The major goals of this retrospective study were to characterize the histologic features in patients with excessive alcohol use who presented with an abnormal hepatic panel and/or abnormal radiographic imaging and did not meet the clinical diagnosis of alcoholic hepatitis or cirrhosis. METHODS: We performed a retrospective study to describe hepatic histology of 62 and 83 excessive drinkers with normal and abnormal serum aspartate transaminase, respectively. The types of inflammatory cells in the liver were characterized by immunohistochemistry for CD4, CD8, CD20, CD68 and myeloperoxidase. RESULTS: Among 62 patients with aspartate aminotransferase (AST) ≤ 50 U/L, 37% had histological evidence of steatosis. Of these, we found evidence of hepatocyte ballooning (21%), lobular inflammation (50%), portal inflammation (52%) and fibrosis (14%). For those with AST > 50 U/L, the presence of hepatic steatosis, lobular inflammation and portal inflammation was observed in 29, 60 and 69% of patients, respectively. Fibrosis was found in 33%, four with bridging fibrosis, and one with cirrhosis. We observed the aggregation of CD68+ macrophages, rather than normally distributed with minimal neutrophilic infiltration. Lobular and portal lymphocytic infiltrations are primarily CD8+ T cells. CONCLUSION: Abnormal hepatic histopathology occurs in excessive drinkers with normal transaminase activity. Future studies to determine the diagnostic modalities to detect such abnormalities and to better understand its clinical implications and long-term outcome are needed.

cHCC-CCA: Consensus terminology for primary liver carcinomas with both hepatocytic and cholangiocytic differentation.

Primary liver carcinomas with both hepatocytic and cholangiocytic differentiation have been referred to as "combined (or mixed) hepatocellular-cholangiocarcinoma." These tumors, although described over 100 years ago, have attracted greater attention recently because of interest in possible stem cell origin and perhaps because of greater frequency and clinical recognition. Currently, because of a lack of common terminology in the literature, effective treatment and predictable outcome data have been challenging to accrue. This article represents a consensus document from an international community of pathologists, radiologists, and clinicians who have studied and reported on these tumors and recommends a working terminology for diagnostic and research approaches for further study and evaluation. CONCLUSION: It is recommended that diagnosis is based on routine histopathology with hematoxylin and eosin (H&E); immunostains are supportive, but not essential for diagnosis. (Hepatology 2018;68:113-126).

Clinicopathological features of He Shou Wu-induced liver injury: This ancient anti-aging therapy is not liver-friendly.

BACKGROUND & AIMS: Polygonum Multiflorum Thumb (PMT), an ancient anti-aging Chinese herb known traditionally as He Shou Wu, has side effects of liver toxicity. To determine the main clinical and pathological characteristics of liver toxicity induced by PMT and the clinical course after its cessation. METHODS: Data of patients, diagnosed as drug-induced liver injury and hospitalised in Beijing Friendship Hospital from August 2005 to August 2017, were retrospectively reviewed. Clinical, pathological data and outcome after cessation of He Shou Wu were obtained and analysed. Kruskal-Wallis and Chi-square (χ2 ) tests were performed. RESULTS: Twenty-nine patients with He Shou Wu-induced liver injury were enrolled. The median age was 53 years (range 15-74) and 75.9% (22/29) were women. The most common symptom was jaundice (79.3%, 23/29). Of nine patients with liver biopsies, six showed acute cholestatic hepatitis, two acute, and one chronic hepatocellular injury pattern. The latency, liver chemistries and outcomes were comparable between pure He Shou Wu (5 patients) and its compounds (24 patients). Twenty-five of 29 patients (86.2%) had normal serum alanine aminotransferase levels after 45 days (range: 10-138 days) and total bilirubin of 46 days (range: 0-551 days). One patient was rechallenged with He Shou Wu and two developed autoimmune features. One patient died of liver failure and three had chronic persistent liver injury. CONCLUSIONS: The main clinicopathological injury pattern of He Shou Wu-induced liver injury is moderate to severe hepatitis with or without cholestasis. Most patients recover completely; however, chronic disease and death do occur.

Primate fetal hepatic responses to maternal obesity: epigenetic signalling pathways and lipid accumulation.

KEY POINTS: Maternal obesity (MO) and exposure to a high-fat, high-simple-carbohydrate diet during pregnancy predisposes offspring to obesity, metabolic and cardiovascular disorders in later life. Underlying molecular pathways and potential epigenetic factors that are dysregulated in MO were identified using unbiased transcriptomic methods. There was increased lipid accumulation and severe steatosis in the MO baboon fetal liver suggesting that these offspring are on an early trajectory of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis. ABSTRACT: Maternal obesity (MO) increases offspring cardiometabolic disease risk. Altered fetal liver development in response to the challenge of MO has metabolic consequences underlying adverse offspring life-course health outcomes. Little is known about the molecular pathways and potential epigenetic changes regulating primate fetal liver responses to MO. We hypothesized that MO would induce fetal baboon liver epigenetic changes resulting in dysregulation of key metabolic pathways that impact lipid metabolism. MO was induced prior to pregnancy by a high-fat, high-fructose diet. Unbiased gene and microRNA (small RNA Seq) abundance analyses were performed on fetal baboon livers at 0.9 gestation and subjected to pathway analyses to identify fetal liver molecular responses to MO. Fetal baboon liver lipid and glycogen content were quantified by the Computer Assisted Stereology Toolbox. In response to MO, fetal livers revealed dysregulation of TCA cycle, proteasome, oxidative phosphorylation, glycolysis and Wnt/ß-catenin signalling pathways together with marked lipid accumulation supporting our hypothesis that multiple pathway dysregulation detrimentally impacts lipid management. This is the first study of MO programming of the non-human primate fetal liver using unbiased transcriptome analysis to detect changes in hepatic gene expression levels and identify potential microRNA epigenetic regulators of metabolic disruption.

Lower expression of tumor microRNA-26a is associated with higher recurrence in patients with hepatocellular carcinoma undergoing surgical treatment.

BACKGROUND AND OBJECTIVES: Hepatocellular carcinoma (HCC) in patients with hepatitis B virus (HBV) exhibit lower tumor microRNA-26a (miR-26a) expression which is associated with worse outcomes. It is unknown if similar miR-26a loss occurs in HCC developed in other liver diseases. We examined tumor miR-26a expression and its impact on recurrence and mortality in a North American HCC cohort. METHODS: MiR-26a levels from tumor and surrounding nontumor liver tissue in 186 subjects were collected. We defined lower tumor expression of miR-26a as <1-fold that of the adjacent nontumor liver tissue. RESULTS: Viral hepatitis (42%; 40% hepatitis C and 2% HBV), alcohol (19%), and nonalcoholic fatty liver disease (NAFLD) (18%) were the most common causes of liver disease. The prevalence of lower tumor miR-26a expression was 68%, and it was evident in HCCs arising in all etiologies (viral hepatitis 60%, alcohol 61%, and NAFLD 76%). Subjects with lower tumor miR-26a expression had significantly higher tumor recurrence (hazard ratio [HR], 2.45; 95% confidence interval [CI], 1.18 to 5.1; P = 0.016) and higher mortality of borderline significance (HR, 1.51; 95% CI, 0.94 to 2.41; P = 0.086). CONCLUSION: Reduced miR-26a expression is a common phenomenon in HCC arising in North American patients with different underlying liver diseases and may increase recurrence and mortality after surgery.

Primary mesenchymal liver tumors of childhood.

Primary mesenchymal tumors of the liver represent a significant proportion of liver tumors among neonates, infants and young children. They may be discovered incidentally or present with an alarmingly large, rapidly growing abdominal mass. One third of pediatric liver tumors are benign with hemangioma and mesenchymal hamartoma being the commonest in that order. Infantile hemangioendothelioma and mesenchymal hamartoma represent the commonest liver tumors among neonates and infants. Mesenchymal hamartoma may even present in utero. A biopsy is often required for definitive diagnosis due to considerable overlap in clinical presentation and radiological findings amongst these tumors, as well as with hepatoblastoma.

Variant differentiation patterns in primary liver carcinoma.

Hepatocellular carcinoma and intrahepatic cholangiocarcinoma are two distinct forms of primary liver carcinoma recognizable at the microscope by their architectural and cytological characteristics, as well as specific immunohistochemical profiles. This straightforward concept however, is increasing imperiled by the recognition of primary liver carcinomas that do not subscribe to a dichotomous paradigm of differentiation, and instead demonstrate biphenotypic differentiation, stem/progenitor cell like features or other variant patterns of differentiation. Appropriate nomenclature, diagnostic criteria, prognostic significance and optimal therapeutic approach for these variant tumors are not completely defined, not leasyt because they are not always identified correctly and when they are, lack of uniform terminology hinders collection of adequate number of cases to facilitate their study. Similar to hepatocellular carcinoma and in contrast with intrahepatic cholangiocarcinoma, primary liver tumors showing biphenotypic differentiation, stem/progenitor cell features or variant differentiation occur mainly, but not always, on a background of chronic liver disease. They are particularly frequent after neo-adjuvant therapy. Whether they represent trans-differentiation of malignant cells, or whether they derive from a stem/progenitor cell that gives rise to divergent differentiation remains yet another area of uncertainty.