Intrahepatic Cholangiocarcinoma Developing in Patients with Metabolic Syndrome Is Characterized by Osteopontin Overexpression in the Tumor Stroma.

Metabolic syndrome (MetS) is a common condition closely associated with non-alcoholic fatty liver disease/non-alcoholic steatohepatitis (NAFLD/NASH). Recent meta-analyses show that MetS can be prodromal to intrahepatic cholangiocarcinoma (iCCA) development, a liver tumor with features of biliary differentiation characterized by dense extracellular matrix (ECM) deposition. Since ECM remodeling is a key event in the vascular complications of MetS, we aimed at evaluating whether MetS patients with iCCA present qualitative and quantitative changes in the ECM able to incite biliary tumorigenesis. In 22 iCCAs with MetS undergoing surgical resection, we found a significantly increased deposition of osteopontin (OPN), tenascin C (TnC), and periostin (POSTN) compared to the matched peritumoral areas. Moreover, OPN deposition in MetS iCCAs was also significantly increased when compared to iCCA samples without MetS (non-MetS iCCAs, n = 44). OPN, TnC, and POSTN significantly stimulated cell motility and the cancer-stem-cell-like phenotype in HuCCT-1 (human iCCA cell line). In MetS iCCAs, fibrosis distribution and components differed quantitatively and qualitatively from non-MetS iCCAs. We therefore propose overexpression of OPN as a distinctive trait of MetS iCCA. Since OPN stimulates malignant properties of iCCA cells, it may provide an interesting predictive biomarker and a putative therapeutic target in MetS patients with iCCA.

The Neglected Role of Bile Duct Epithelial Cells in NASH.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide, and affects 25% of the population in Western countries. NAFLD is the hepatic manifestation of the metabolic syndrome, linked to insulin resistance, which is the common pathogenetic mechanism. In approximately 40% of NAFLD patients, steatosis is associated with necro-inflammation and fibrosis, resulting in nonalcoholic steatohepatitis (NASH), a severe condition that may progress to cirrhosis and liver cancer. Although the hepatocyte represents the main target of the disease, involvement of the bile ducts occurs in a subset of patients with NASH, and is characterized by ductular reaction and activation of the progenitor cell compartment, which incites portal fibrosis and disease progression. We aim to dissect the multiple biological effects that adipokines and metabolic alterations exert on cholangiocytes to derive novel information on the mechanisms driven by insulin resistance, which promote fibro-inflammation and carcinogenesis in NASH.

A Nutraceutical Formulation Containing Brown Algae Reduces Hepatic Lipid Accumulation by Modulating Lipid Metabolism and Inflammation in Experimental Models of NAFLD and NASH.

Recently, some preclinical and clinical studies have demonstrated the ability of brown seaweeds in reducing the risk factors for metabolic syndrome. Here, we analyzed the beneficial effect of a nutraceutical formulation containing a phytocomplex extracted from seaweeds and chromium picolinate in animal models of liver steatosis of differing severities (rats with non-alcoholic fatty liver disease (NAFLD) and its complication, non-alcoholic steatohepatitis (NASH)). This treatment led to a significant drop in hepatic fat deposition in both models (p < 0.01 vs. untreated animals), accompanied by a reduction in plasma inflammatory cytokines, such as interleukin 6, tumor necrosis factor α, and C reactive protein, and myeloperoxidase expression in liver tissue. Furthermore, a modulation of the molecular pathways involved in lipid metabolism and storage was demonstrated, since we observed the significant reduction of the mRNA levels of fatty acid synthase, diacylglycerol acyltransferases, the sterol-binding protein SREBP-1, and the lipid transporter perilipin-2, in both treated NAFLD and NASH rats in comparison to untreated ones. In conclusion, this nutraceutical product was effective in reducing liver steatosis and showed further beneficial effects on hepatic inflammation and glycemic control, which were particularly evident in rats characterized by a more severe condition, thus representing a therapeutic option for the treatment of NAFLD and NASH patients.

Pathology of non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of different conditions which are characterized by hepatic steatosis in the absence of secondary causes. It is currently the most common chronic liver disease worldwide, and its estimated prevalence is about 1.5-6.5%. The only histological finding of steatosis ("simple" steatosis) represents the uncomplicated form of NAFLD, while non-alcoholic steatohepatitis (NASH) is its inflammatory subtype associated with disease progression to cirrhosis and hepatocellular carcinoma (HCC), and represents the major indication for liver transplantation. NASH is still a diagnostic and therapeutic challenge for clinicians and liver biopsy is currently the only accepted method to reliably distinguish NASH from "simple" steatosis. From the histological perspectives, NAFLD and NASH continue to be an area of active interest for pathologists, with a specific focus on better methods of evaluation, morphologic clues to pathogenesis, and predictors of fibrosis progression. This review focuses on histopathology of NAFLD in adults, with the aim to provide a practical diagnostic approach useful in the clinical routine.

Hepatocellular carcinoma: a clinical and pathological overview.

HCC incidence rates have been rising in the past 3 decades and by 2025 > 1 million individuals will be affected annually. High-throughput sequencing technologies led to the identification of several molecular HCC subclasses that can be broadly grouped into 2 major subgroups, each characterized by specific morphological and phenotypical features. It is likely that this increasing knowledge and a more appropriate characterization of HCC at the pathological level will impact HCC patient management.

Benign biliary neoplasms and biliary tumor precursors.

Benign biliary tumor are common lesions that are often an incidental finding in subjects who undergo medical imaging tests for other conditions. Most are true neoplasms while few result from reactive or malformative proliferation. Benign tumors have no clinical consequences, although the premalignant nature or potential for malignant transformation is of concern in some cases. The main practical problem for pathologists is the need to differentiate them from malignant biliary tumours, which is not always straightforward.Premalignant lesions of the bile duct have been described, although their incidence has been poorly characterized. These lesions include biliary mucinous cystic neoplasms, intraductal papillary neoplasms of the bile duct, and biliary intraepithelial neoplasia. In this article, histopathology of benign biliary tumors and biliary tumor precursors is discussed, with a focus on the main diagnostic criteria.

Cholangiocarcinoma.

Liver cancer represents the third leading cause of cancer-related death worldwide. Cholangiocarcinoma (CCA) is the second most common type of liver cancer after hepatocellular carcinoma, accounting for 10-15% of all primary liver malignancies. Both the incidence and mortality of CCA have been steadily increasing during the last decade. Moreover, most CCAs are diagnosed at an advanced stage, when therapeutic options are very limited.CCA may arise from any tract of the biliary system and it is classified into intrahepatic, perihilar, and distal CCA, according to the anatomical site of origin. This topographical classification also reflects distinct genetic and histological features, risk factors, and clinical outcomes. This review focuses on histopathology of CCA, its differential diagnoses, and its diagnostic pitfalls.

Autoimmune biliary diseases: primary biliary cholangitis and primary sclerosing cholangitis.

Autoimmune cholestatic liver diseases are rare hepato-biliary disorders characterized by a progressive, inflammatory destruction of bile ducts. Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are the main autoimmune cholestatic liver diseases. Both may evolve into secondary biliary cirrhosis and its complications. Therapeutic options are limited and liver transplantation remains the only definitive treatment for PBC and PSC.Most PBC and PSC patients have a typical presentation, which does not require liver biopsy. However, in routine clinical practice, important variants or specific subgroups that benefit from liver biopsy for proper management may be observed. Herein, we provide a general overview of clinical and pathological characteristic of PBC and PSC, highlighting the most important features for routine diagnostic practice.

Pathology of autoimmune hepatitis.

Autoimmune hepatitis (AIH) is a relatively rare non-resolving chronic liver disease, which mainly affects women. It is characterized by hypergammaglobulinemia, circulating autoantibodies, interface hepatitis on liver histology and a favourable response to immunosuppression. The putative mechanism for the development of autoimmune hepatitis is thought to be the interaction between genetic predisposition, environmental triggers and failure of the native immune system.AIH still remains a major diagnostic and therapeutic challenge, mainly because it is a very heterogeneous disease. Prompt and timely diagnosis is crucial since, if left untreated, AIH has a high mortality rate. Histological demonstration of hepatitis is required for the diagnosis of AIH and, therefore, liver biopsy is mandatory in the initial diagnostic work-up, before treatment. In this review, we summarize the histological features of AIH with the main aim of highlighting the most important clinical-pathological hallmarks useful in the routine diagnostic practice.

Fucus vesiculosus and Ascophyllum nodosum Ameliorate Liver Function by Reducing Diet-Induced Steatosis in Rats.

The Asian coastal communities have used the brown seaweeds Fucus vesiculosus and Ascophyllum nodosum since ancient times. Recently, some in vitro and in vivo studies have demonstrated their abilities in reducing risk factors for metabolic syndrome. Here, we analyzed the protective effect of a phytocomplex extracted from these seaweeds on the deposition of fat in the liver after the administration of a high-fat diet (HFD) to rats for five weeks. The administration of F. vesiculosus and A. nodosum led to significant reductions in microvescicular steatosis and plasma biochemical and lipid parameters, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total and conjugated bilirubin, and triglycerides. Furthermore, the postprandial glycemic peak was delayed and significantly reduced (p < 0.01) by the algal extract administration. In conclusion, this extract is effective in reducing microvescicular steatosis and improving glycemic control, thereby lowering the risk of nonalcoholic fatty liver disease, obesity, and diabetes, diseases related to the consumption of fat and sugar-enriched diets.

Focus on histological abnormalities of intrahepatic vasculature in chronic viral hepatitis.

BACKGROUND & AIMS: The histological intrahepatic microvasculature lesions have not been deeply investigated outside the setting of portal hypertension. The aim of this study was to analyse the type and the prevalence of microvasculature abnormalities and their correlation with inflammatory activity, fibrosis stage and tissue markers of fibrogenesis, angiogenesis and oxidative DNA damage in liver biopsies obtained from patients with chronic viral hepatitis. METHODS: Seventy-four liver biopsies from untreated patients affected by hepatitis B (22 cases) and C (52 cases) were included. The presence of microvascular changes was correlated with (i) the severity of the activity and fibrosis; (ii) immunohistochemical markers of angiogenesis (CD34) and hepatic stellate cells activation (alpha-smooth muscle actin); (iii) a tissue marker of oxidative damage (8-OHdG adducts). RESULTS: Sixty-five out of 74 biopsies (87.8%) showed vascular lesions. Portal angiomatosis was the most prevalent (62.2%) and it was associated with, on 1 side, the fibrosis stage at both univariate (P < .0001) and multivariate analysis (P = .01, OR = 9.4 [1.6-54]) and, on the other, with angiogenesis (P = .05) and hepatic stellate cells activation (P = .002). Interestingly, 36/46 cases with portal angiomatosis were at early/intermediate fibrosis stage. The hepatic stellate cells activation was also associated with the presence of aberrant periportal vessels (P = .01). CONCLUSIONS: The histological alterations of intrahepatic microvasculature, usually seen in cirrhosis and portal hypertension, occur in chronic viral hepatitis even at early/intermediate fibrosis stages. Their correlation with angiogenesis and fibrogenesis supports a possible involvement in disease progression.

Metastasis to parotid gland from non Head and Neck tumors.

PURPOSE: Most primary tumors spreading metastasis to the parotid gland are usually located in the head and neck region, nonetheless, rarely, parotid gland can also be the target of metastatic localization site of distant primary tumors. The purpose of this study was to describe a clinical series of metastasis to the parotid gland from distant primary tumors (non Head & Neck). METHODS: The clinical databases of parotid tumors in two academic centers have been analyzed and 11 cases of parotid metastatic cancers from distant primary tumors were found. RESULTS: Primary tumor was lung cancer in 8 cases, and breast cancer, gastric carcinoma and pancreatic carcinoma in one case each. CONCLUSIONS: Parotid metastases can be the first clinical manifestation of a malignant tumor from a distant site and can manifest years after curative-intent treatment of the distant primary. Histopathology and immunohistochemistry can help in the identification of the primary site. Parotidectomy with complete excision of the parotid lesion may have diagnostic and/or loco-regional control and/or curative intent, however there is still no international consensus about the therapy of parotid malignant metastasis.

Obliterative portal venopathy without portal hypertension: an underestimated condition.

BACKGROUND & AIMS: Obliterative portal venopathy without portal hypertension has been described by a single study in a limited number of patients, thus very little is known about this clinical condition. This study aimed to investigate the prevalence of obliterative portal venopathy and its clinical-pathological correlations in patients with cryptogenic chronic liver test abnormalities without clinical signs of portal hypertension. METHODS: We analysed 482 liver biopsies from adults with non-cirrhotic cryptogenic chronic liver disorders and without any clinical signs of portal hypertension, consecutively enrolled in a 5-year period. Twenty cases of idiopathic non-cirrhotic portal hypertension diagnosed in the same period, were included for comparison. Histological findings were matched with clinical and laboratory features. RESULTS: Obliterative portal venopathy was identified in 94 (19.5%) of 482 subjects and in all 20 cases of idiopathic non-cirrhotic portal hypertension: both groups shared the entire spectrum of histological changes described in the latter condition. The prevalence of incomplete fibrous septa and nodular regenerative hyperplasia was higher in the biopsies of idiopathic non-cirrhotic portal hypertension (P = 0.006 and P = 0.002), a possible hint of a more advanced stage of the disease. The two groups also shared several clinical laboratory features, including a similar liver function test profile, concomitant prothrombotic conditions and extrahepatic autoimmune disorders. CONCLUSION: Obliterative portal venopathy occurs in a substantial proportion of patients with unexplained chronic abnormal liver function tests without portal hypertension. The clinical-pathological profile of these subjects suggests that they may be in an early (non-symptomatic) stage of idiopathic non-cirrhotic portal hypertension.

Changes in microRNA expression during disease progression in patients with chronic viral hepatitis.

BACKGROUND & AIMS: MicroRNAs (miRNAs) have been involved in hepatocarcinogenesis, but little is known on their role in the progression of chronic viral hepatitis. Aim of this study was to identify miRNA signatures associated with stages of disease progression in patients with chronic viral hepatitis. METHODS: MiRNA expression profile was investigated in liver biopsies from patients with chronic viral hepatitis and correlated with clinical, virological and histopathological features. Relevant miRNAs were further investigated. RESULTS: Most of the significant changes in miRNA expression were associated with liver fibrosis stages and included the significant up-regulation of a group of miRNAs that were demonstrated to target the master regulators of epithelial-mesenchymal transition ZEB1 and ZEB2 and involved in the preservation of epithelial cell differentiation, but also in cell proliferation and fibrogenesis. In agreement with miRNA data, immunostaining of liver biopsies showed that expression of the epithelial marker E-cadherin was maintained in severe fibrosis/cirrhosis while expression of ZEBs and other markers of epithelial-mesenchymal transition were low or absent. Severe liver fibrosis was also significantly associated with the down-regulation of miRNAs with antiproliferative and tumour suppressor activity. Similar changes in miRNA and target gene expression were demonstrated along with disease progression in a mouse model of carbon tetrachloride (CCl4)-induced liver fibrosis, suggesting that they might represent a general response to liver injury. CONCLUSION: Chronic viral hepatitis progression is associated with the activation of miRNA pathways that promote cell proliferation and fibrogenesis, but preserve the differentiated hepatocyte phenotype.

Primary Sclerosing Cholangitis: Diagnostic Criteria.

Primary sclerosing cholangitis is a chronic cholestatic liver disease characterized by inflammation and fibrosis of intra- and/or extrahepatic bile ducts leading to the formation of multifocal strictures alternated to bile duct dilatations. The diagnosis of the most common subtype of the disease, the large duct PSC, is based on the presence of elevation of cholestatic indices, the association of typical cholangiographic findings assessed by magnetic resonance cholangiography and the exclusion of causes of secondary sclerosing cholangitis. Liver biopsy is not routinely applied for the diagnosis of large duct PSC but is mandatory in the case of suspicion of small duct PSC or overlap with autoimmune hepatitis.

The phenolic compounds tyrosol and hydroxytyrosol counteract liver fibrogenesis via the transcriptional modulation of NADPH oxidases and oxidative stress-related miRNAs.

Liver fibrosis is the result of a chronic pathological condition caused by the activation of hepatic stellate cells (HSCs), which induces the excessive deposition of extracellular matrix. Fibrogenesis is sustained by an exaggerated production of reactive oxidative species (ROS) by NADPH oxidases (NOXs), which are overactivated in hepatic inflammation. In this study, we investigated the antifibrotic properties of two phenolic compounds of natural origin, tyrosol (Tyr) and hydroxytyrosol (HTyr), known for their antioxidant and anti-inflammatory effects. We assessed Tyr and HTyr antifibrotic and antioxidant activity both in vitro, by a co-culture of LX2, HepG2 and THP1-derived Mϕ macrophages, set up to simulate the hepatic microenvironment, and in vivo, in a mouse model of liver fibrosis obtained by carbon tetrachloride treatment. We evaluated the mRNA and protein expression of profibrotic and oxidative markers (α-SMA, COL1A1, NOX1/4) by qPCR and/or immunocytochemistry or immunohistochemistry. The expression of selected miRNAs in mouse livers were measured by qPCR. Tyr and HTyr reduces fibrogenesis in vitro and in vivo, by downregulating all fibrotic markers. Notably, they also modulated oxidative stress by restoring the physiological levels of NOX1 and NOX4. In vivo, this effect was accompanied by a transcriptional regulation of inflammatory genes and of 2 miRNAs involved in the control of oxidative stress damage (miR-181-5p and miR-29b-3p). In conclusion, Tyr and HTyr exert antifibrotic and anti-inflammatory effects in preclinical in vitro and in vivo models of liver fibrosis, by modulating hepatic oxidative stress, representing promising candidates for further development.

Ferroptosis in Intrahepatic Cholangiocarcinoma: IDH1105GGT Single Nucleotide Polymorphism Is Associated With Its Activation and Better Prognosis.

Objectives: Intrahepatic cholangiocarcinoma (ICC) has a dismal prognosis and often demonstrates an anti-apoptotic landscape, which is a key step to chemotherapy resistance. Isocitrate dehydrogenase 1 or 2 (IDH1-2)-mutated ICCs have been described and associated with better prognosis. Ferroptosis is a regulated iron-mediated cell death induced by glutathione peroxidase 4 (GPX4) inhibition, and may be triggered pharmacologically. GPX4 is overexpressed in aggressive cancers, while its expression is inhibited by IDH1 R132C mutation in cell lines. We investigated tissue expression of ferroptosis activation markers in ICC and its correlation with clinical-pathological features and IDH1-2 status. Materials and Methods: We enrolled 112 patients who underwent hepatic resection or diagnostic liver biopsy for ICC. Immunostaining for transferrin-receptor 1 and GPX4, and Pearls' stain for iron deposits were performed to evaluate ferroptosis activation. Immunostaining for STAT3 was performed to study pro-inflammatory and anti-apoptotic landscape. Main IDH1-2 mutations were investigated in 90 cases by real-time polymerase chain reaction. Results: GPX4 overexpression was seen in 79.5% of cases and related to poor histological prognostic factors (grading and perineural and vascular invasion; p < 0.005 for all) and worse prognosis (OS p = 0.03; DFS p = 0.01). STAT3 was expressed in 95.5% of cases, confirming the inflammation-related anti-apoptotic milieu in ICC, and directly related to GPX4 expression (p < 0.0001). A high STAT3 expression correlated to a worse prognosis (OS p = 0.02; DFS p = 0.001). Nearly 12% of cases showed IDH1 105GGT single nucleotide polymorphism, which was never described in ICC up to now, and was related to lower tumor grade (p < 0.0001), longer overall survival (p = 0.04), and lower GPX4 levels (p = 0.001). Conclusion: Our study demonstrates for the first time that in most inflammatory ICCs ferroptosis is not active, and its triggering is related to IDH1-2 status. This supports the possible therapeutic role of ferroptosis-inducer drugs in ICC patients, especially in drug-resistant cases.

Case Report: An early-onset inflammatory colitis due to a variant in TNFAIP3 causing A20 haploinsufficiency.

Autoinflammatory diseases (AID) are a heterogeneous group of inherited conditions caused by abnormal activation of systems mediating innate immunity. Recent literature focuses on A20 Haploinsufficiency, an autoinflammatory disease with a phenotype resembling Behçet disease (BD). It is caused by loss-of-function mutations in TNFAIP3 gene that result in the activation of a pro-inflammatory pathway. In this case report we describe a one-year-old baby who came to our attention for hematochezia appeared at three months of age which was considered an expression of early-onset colitis. The following appearance of cutaneous inflammation Behçet-like and the positive family history concurred with the diagnosis of an autoinflammatory disease. Extended genetic tests in the patient allowed to identify a heterozygous variant in TNFAIP3 [NM_006290.4:c.460G > T, p.(Glu154Ter)], not previously described and not present in the GnomAD database. As a consequence the diagnosis A20 Haploinsufficiency was established and the appropriate management was started. The same TNFAIP3 variant was also found in her father who had suffered from recurrent oral aphthosis, vitiligo and thyroiditis since childhood. In conclusion, we described a young patient with a novel heterozygous mutation in TNFAIP3 who developed BD-like symptoms. We proposed that loss-of-function variants in TNFAIP3 may be associated with a very early-onset intestinal BD phenotype.

The Metabolic Activation of Sofosbuvir Is Impaired in an Experimental Model of NAFLD.

The effect of liver steatosis on drug metabolism has been investigated in both preclinical and clinical settings, but the findings of these studies are still controversial. We here evaluated the pharmacokinetic profile of the main sofosbuvir metabolite GS-331007 in healthy animals and rats with non-alcoholic fatty liver disease (NAFLD) after the oral administration of a single 400 mg/kg dose of sofosbuvir. The plasma concentration of GS-331007 was evaluated by HPLC-MS. The expression of the two enzymes uridine monophosphate-cytidine monophosphate kinase 1 (UMP-CMPK1), and nucleoside diphosphate kinase (ND-PK), responsible for the formation of the active metabolite GS-331007-TP, were measured by qRT-PCR and Western Blot. We demonstrated that in rats with steatosis, the area under the plasma concentration-vs-time curve (AUC) and the peak plasma concentration (Cmax) of GS-331007 increased significantly whereas the expression of UMP-CMPK was significantly lower than that of healthy animals. The reduction of UMP-CMPK expression suggests an impairment of sofosbuvir activation to GS-331007-TP, giving a possible explanation for the reduction of sofosbuvir efficacy in patients affected by genotype 3 Hepatitis C virus (HCV), which is often associated with liver steatosis. Furthermore, since GS-331007 plasma concentration is altered by steatosis, it can be suggested that the plasma concentration of this metabolite may not be a reliable indicator for exposure-response analysis in patients with NAFLD.

Translational Value of Tumor-Associated Lymphangiogenesis in Cholangiocarcinoma.

The prognosis of cholangiocarcinoma remains poor in spite of the advances in immunotherapy and molecular profiling, which has led to the identification of several targetable genetic alterations. Surgical procedures, including both liver resection and liver transplantation, still represent the treatment with the best curative potential, though the outcomes are significantly compromised by the early development of lymph node metastases. Progression of lymphatic metastasis from the primary tumor to tumor-draining lymph nodes is mediated by tumor-associated lymphangiogenesis, a topic largely overlooked until recently. Recent findings highlight tumor-associated lymphangiogenesis as paradigmatic of the role played by the tumor microenvironment in sustaining cholangiocarcinoma invasiveness and progression. This study reviews the current knowledge about the intercellular signaling and molecular mechanism of tumor-associated lymphangiogenesis in cholangiocarcinoma in the hope of identifying novel therapeutic targets to halt a process that often limits the success of the few available treatments.