Exhaled breath analysis in hepatology: State-of-the-art and perspectives

Liver disease is characterized by breath exhalation of peculiar volatile organic compounds(VOCs).Thanks to the availability of sensitive technologies for breath analysis,this empiric approach has recently gained increasing attention in the context of hepatology,following the good results obtained in other fields of medicine.After the first studies that led to the identification of selected VOCs for pathophysiological purposes,subsequent research has progressively turned towards the comprehensive assessment of exhaled breath for potential clinical application.Specific VOC patterns were found to discriminate subjects with liver cirrhosis,to rate disease severity,and,eventually,to forecast adverse clinical outcomes even beyond existing scores.Preliminary results suggest that breath analysis could be useful also for detecting and staging hepatic encephalopathy and for predicting steatohepatitis in patients with nonalcoholic fatty liver disease.However,clinical translation is still hampered by a number of methodological limitations,including the lack of standardization and the consequent poor comparability between studies and the absence of external validation of obtained results.Given the low-cost and easy execution at bedside of the new technologies(e-nose),larger and well-structured studies are expected in order to provide the adequate level of evidence to support VOC analysis in clinical practice.

Chronic hepatitis B virus infection in Eastern Ethiopia:Clinical characteristics and determinants of cirrhosis

BACKGROUND Chronic hepatitis B(CHB)virus infection is a major cause of liver-associated morbidity and mortality,particularly in low-income countries.A better understanding of the epidemiological,clinical,and virological characteristics of CHB will guide appropriate treatment strategies and improve the control and management of CHB in Ethiopia.AIM To investigate the characteristics of CHB in Eastern Ethiopia and assess the efficacy and safety of antiviral treatment.METHODS This cohort study included 193 adults who were human immunodeficiency virus-negative with CHB between June 2016 and December 2019.Baseline assessments included chemistry,serologic,and viral markers.χ^(2) tests,Mann-Whitney U tests,and logistic regression analyses were used to identify the determinants of cirrhosis.Tenofovir disoproxil fumarate(TDF)was initiated using treatment criteria from the Ethiopian CHB pilot program.RESULTS A total of 132 patients(68.4%)were men,with a median age of 30 years[interquartile range(IQR):24-38].At enrollment,60(31.1%)patients had cirrhosis,of whom 35(58.3%)had decompensated cirrhosis.Khat use,hepatitis B envelope antigen positivity,and a high viral load were independently associated with cirrhosis.Additionally,66 patients(33.4%)fulfilled the treatment criteria and 59(30.6%)started TDF.Among 29 patients who completed 24 months of treatment,the median aspartate aminotransferase to platelet ratio index declined from 1.54(IQR:0.66-2.91)to 1.10(IQR:0.75-2.53)(P=0.002),and viral suppression was achieved in 80.9%and 100%of patients after 12 months and 24 months of treatment,respectively.Among the treated patients,12(20.3%)died within the first 6 months of treatment,of whom 8 had decompensated cirrhosis.CONCLUSION This study highlights the high prevalence of cirrhosis,initial mortality,and the efficacy of TDF treatment.Scaling up measures to prevent and control CHB infections in Ethiopia is crucial.

Management of autoimmune hepatitis induced by hepatitis delta virus

Approximately 12-72 million people worldwide are co-infected with hepatitis B virus(HBV)and hepatitis delta virus(HDV).This concurrent infection can lead to several severe outcomes with hepatic disease,such as cirrhosis,fulminant hepatitis,and hepatocellular carcinoma,being the most common.Over the past few decades,a correlation between viral hepatitis and autoimmune diseases has been reported.Furthermore,autoantibodies have been detected in the serum of patients co-infected with HBV/HDV,and autoimmune features have been reported.However,to date,very few cases of clinically significant autoimmune hepatitis(AIH)have been reported in patients with HDV infection,mainly in those who have received treatment with pegylated interferon.Interestingly,there are some patients with HBV infection and AIH in whom HDV infection is unearthed after receiving treatment with immunosuppressants.Consequently,several questions remain unanswered with the challenge to distinguish whether it is autoimmune or“autoimmune-like”hepatitis being the most crucial.Second,it remains uncertain whether autoimmunity is induced by HBV or delta virus.Finally,we investigated whether the cause of AIH lies in the previous treatment of HDV with pegylated interferon.These pressing issues should be elucidated to clarify whether new antiviral treatments for HDV,such as Bulevirtide or immu-nosuppressive drugs,are more appropriate for the management of patients with HDV and AIH.

Overlapping approach Proton Pump Inhibitors/Nux vomica-Heel as new intervention for gastro-esophageal reflux management:Delphi consensus study

BACKGROUND Gastro-esophageal reflux disease(GERD)may affect the upper digestive tract;up to 20%of population in Western nations are affected by GERD.Antacids,histamine H2-receptor antagonists,and Proton Pump Inhibitors(PPIs)are considered the referring medications for GERD.Nevertheless,PPIs must be managed carefully because their use,especially chronic,could be linked with some adverse effects.An effective and safe alternative pharmacological tool for GERD is needed.After the identification of potentially new medications to flank PPIs,it is mandatory to revise and improve good clinical practices even through a consensus process.AIM To optimize diagnosis and treatment guidelines for GERD through a consensus based on Delphi method.METHODS The availability of clinical studies describing the action of the multicomponent/multitarget medication Nux vomica-Heel,subject of the consensus,is the basic prerequisite for the consensus itself.A modified Delphi process was used to reach a consensus among a panel of Italian GERD specialists on the overlapping approach PPIs/Nux vomica-Heel as a new intervention model for the management of GERD.The Voting Consensus group was composed of 49 Italian Medical Doctors with different specializations:Gastroenterology,otolaryngology,geriatrics,and general medicine.A scientific committee analyzed the literature,determined areas that required investigation(in agreement with the multiple-choice questionnaire results),and identified two topics of interest:(1)GERD disease;and(2)GERD treatment.Statements for each of these topics were then formulated and validated.The Delphi process involved two rounds of questioning submitted to the panel experts using an online platform.RESULTS According to their routinary GERD practice and current clinical evidence,the panel members provided feedback to each questionnaire statement.The experts evaluated 15 statements and reached consensus on all 15.The statements regarding the GERD disease showed high levels of agreement,with consensus ranging from 70%to 92%.The statements regarding the GERD treatment also showed very high levels of agreement,with consensus ranging from 90%to 100%.This Delphi process was able to reach consensus among physicians in relevant aspects of GERD management,such as the adoption of a new approach to treat patients with GERD based on the overlapping between PPIs and Nux vomica-Heel.The consensus was unanimous among the physicians with different specializations,underlying the uniqueness of the agreement reached to identify in the overlapping approach between PPIs and Nux vomica-Heel a new intervention model for GERD management.The results support that an effective approach to deprescribe PPIs through a progressive decalage timetable(reducing PPIs administration to as-needed use),should be considered.CONCLUSION Nux vomica-Heel appears to be a valid opportunity for GERD treatment to favor the deprescription of PPIs and to maintain low disease activity together with the symptomatology remission.

Development and validation of a predictive model for acute-onchronic liver failure after transjugular intrahepatic portosystemic shunt

BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS)is a cause of acute-onchronic liver failure(ACLF).AIM To investigate the risk factors of ACLF within 1 year after TIPS in patients with cirrhosis and construct a prediction model.METHODS In total,379 patients with decompensated cirrhosis treated with TIPS at Nanjing Drum Tower Hospital from 2017 to 2020 were selected as the training cohort,and 123 patients from Nanfang Hospital were included in the external validation cohort.Univariate and multivariate logistic regression analyses were performed to identify independent predictors.The prediction model was established based on the Akaike information criterion.Internal and external validation were conducted to assess the performance of the model.RESULTS Age and total bilirubin(TBil)were independent risk factors for the incidence of ACLF within 1 year after TIPS.We developed a prediction model comprising age,TBil,and serum sodium,which demonstrated good discrimination and calibration in both the training cohort and the external validation cohort.CONCLUSION Age and TBil are independent risk factors for the incidence of ACLF within 1 year after TIPS in patients with decompensated cirrhosis.Our model showed satisfying predictive value.

Prevalence and risk factors for impaired renal function among Asian patients with nonalcoholic fatty liver disease

Background:Nonalcoholic fatty liver disease(NAFLD)is associated with impaired renal function,and both diseases often occur alongside other metabolic disorders.However,the prevalence and risk factors for impaired renal function in patients with NAFLD remain unclear.The objective of this study was to identify the prevalence and risk factors for renal impairment in NAFLD patients.Methods:All adults aged 18-70 years with ultrasound-diagnosed NAFLD and transient elastography examination from eight Asian centers were enrolled in this prospective study.Liver fibrosis and cirrhosis were assessed by FibroScan-aspartate aminotransferase(FAST),Agile 3+and Agile 4 scores.Impaired renal function and chronic kidney disease(CKD)were defined by an estimated glomerular filtration rate(eGFR)with value of<90 mL/min/1.73 m^(2) and<60 mL/min/1.73 m^(2),respectively,as estimated by the CKD-Epidemiology Collaboration(CKD-EPI)equation.Results:Among 529 included NAFLD patients,the prevalence rates of impaired renal function and CKD were 37.4%and 4.9%,respectively.In multivariate analysis,a moderate-high risk of advanced liver fibrosis and cirrhosis according to Agile 3+and Agile 4 scores were independent risk factors for CKD(P<0.05).Furthermore,increased fasting plasma glucose(FPG)and blood pressure were significantly associated with impaired renal function after controlling for the other components of metabolic syndrome(P<0.05).Compared with patients with normoglycemia,those with prediabetes[FPG≥5.6 mmol/L or hemoglobin A1c(HbA1c)≥5.7%]were more likely to have impaired renal function(P<0.05).Conclusions:Agile 3+and Agile 4 are reliable for identifying NAFLD patients with high risk of CKD.Early glycemic control in the prediabetic stage might have a potential renoprotective role in these patients.

Vulvar Swelling in a 12-Year-Old Girl: An Early Manifestation of Crohn’s Disease

Vulvar Crohn’s disease (VCD) is a rare complication of Crohn’s disease, especially in pediatric population. An early diagnosis can result difficult if the complication does not present in conjunction with the classic gastrointestinal symptoms that characterize this disease. In this study we present the case of a 12-year-old girl whose initial symptom of Crohn’s disease was a symptomatic vulvar swelling promoted by a rectovaginal fistula. We also provide an overview of Crohn’s disease and the vulvar changes found in the course of this disease.

Characterization of acute-on-chronic liver diseases: A multicenter prospective cohort study

BACKGROUND Acute-on-chronic liver disease(AoCLD)accounts for the majority of patients hospitalized in the Department of Hepatology or Infectious Diseases.AIM To explore the characterization of AoCLD to provide theoretical guidance for the accurate diagnosis and prognosis of AoCLD.METHODS Patients with AoCLD from the Chinese Acute-on-Chronic Liver Failure(ACLF)study cohort were included in this study.The clinical characteristics and outcomes,and the 90-d survival rate associated with each clinical type of AoCLD were analyzed,using the Kaplan-Meier method and the log-rank test.RESULTS A total of 3375 patients with AoCLD were enrolled,including 1679(49.7%)patients with liver cirrhosis acute decompensation(LC-AD),850(25.2%)patients with ACLF,577(17.1%)patients with chronic hepatitis acute exacer-bation(CHAE),and 269(8.0%)patients with liver cirrhosis active phase(LC-A).The most common cause of chronic liver disease(CLD)was HBV infection(71.4%).The most common precipitants of AoCLD was bacterial infection(22.8%).The 90-d mortality rates of each clinical subtype of AoCLD were 43.4%(232/535)for type-C ACLF,36.0%(36/100)for type-B ACLF,27.0%(58/215)for type-A ACLF,9.0%(151/1679)for LC-AD,3.0%(8/269)for LC-A,and 1.2%(7/577)for CHAE.CONCLUSION HBV infection is the main cause of CLD,and bacterial infection is the main precipitant of AoCLD.The most common clinical type of AoCLD is LC-AD.Early diagnosis and timely intervention are needed to reduce the mortality of patients with LC-AD or ACLF.

Cystic tumors of the liver:A practical approach

Biliary cyst tumors(cystadenoma and cystadeno-carcinoma) are an indication for liver resection. They account for only 5% of all solitary cystic lesions of the liver,but differential diagnosis with multiloculated or complicated biliary cysts,atypical hemangiomas,hamartomas and lymphangiomas may be difficult. The most frequent challenge is to differentiate biliary cyst tumors from hemorrhagic cysts. Computerized tomography(CT) and magnetic resonance imaging(MRI) are often not diagnostic and in these cases fine needle aspiration(FNA) is used to confirm the presence of atypical biliary cells. FNA,however,lacks adequate sensitivity and specificity and should always be used in conjunction with imaging. Pre-operative differentiation of cystadenoma from cystadenocarcinoma is impossible and surgery must be performed if a biliary cyst tumor is suspected. When multiple cystic lesions are observed throughout the liver parenchyma,it is important to exclude liver metastasis,of which colonic cancer is the most common primary site. Multiple biliary hamartomas(von Meyenburg complex) can appear as a mixture of solid and cystic lesions and can be confused with cystic metastasis. Strong and uniform T2 hyperintensity on MRI is usually diagnostic,but occasionally a percutaneous biopsy may be required.

Microwave ablation of hepatocellular carcinoma

Although surgical resection is still the optimal treatment option for early-stage hepatocellular carcinoma(HCC) in patients with well compensated cirrhosis,thermal ablation techniques provide a valid nonsurgical treatment alternative,thanks to their minimal invasiveness,excellent tolerability and safety profile,proven efficacy in local disease control,virtually unlimited repeatability and cost-effectiveness.Different energy sources are currently employed in clinics as physical agents for percutaneous or intra-surgical thermal ablation of HCC nodules.Among them,radiofrequency(RF) currents are the most used,while microwave ablations(MWA) are becoming increasingly popular.Starting from the 90s',RF ablation(RFA) rapidly became the standard of care in ablation,especially in the treatment of small HCC nodules;however,RFA exhibits substantial performance limitations in the treatment of large lesions and/or tumors located near major heat sinks.MWA,first introduced in the Far Eastern clinical practice in the 80s',showing promising results but also severe limitations in the controllability of the emitted field and in the high amount of power employed for the ablation of large tumors,resulting in a poor coagulative performance and a relatively high complication rate,nowadays shows better results both in terms of treatment controllability and of overall coagulative performance,thanks to the improvement of technology.In this review we provide an extensive and detailed overview of the key physical and technical aspects of MWA and of the currently available systems,and we want to discuss the most relevant published data on MWA treatments of HCC nodules in regard to clinical results and to the type and rate of complications,both in absolute terms and in comparison with RFA.

Liver transplantation for hepatocellular carcinoma: Where do we stand?

Hepatocellular carcinoma represents an important cause of morbidity and mortality worldwide. It is the sixth most common cancer and the fourth leading cause of cancer death. Liver transplantation is a key tool for the treatment of this disease in human therefore hepatocellular carcinoma is increasing as primary indication for grafting. Although liver transplantation represents an outstanding therapy for hepatocellular carcinoma, due to organ shortage, the careful selection and management of patients who may have a major survival benefit after grafting remains a fundamental question. In fact, only some stages of the disease seem amenable of this therapeutic option, stimulating the debate on the appropriate criteria to select candidates. In this review we focused on current criteria to select patients with hepatocellular carcinoma for liver transplantation as well as on the strategies (bridging) to avoid disease progression and exclusion from grafting during the stay on wait list. The treatments used to bring patients within acceptable criteria (down-staging), when their tumor burden exceeds the standard criteria for transplant, are also reported. Finally, we examined tumor reappearance following liver transplantation. This occurrence is estimated to be approximately 8%-20% in different studies. The possible approaches to prevent this outcome after transplant are reported with the corresponding results.

Predictors of early and late hepatocellular carcinoma recurrence

Hepatocellular carcinoma(HCC)is the most frequent liver neoplasm,and its incidence rates are constantly increasing.Despite the availability of potentially curative treatments(liver transplantation,surgical resection,thermal ablation),long-term outcomes are affected by a high recurrence rate(up to 70%of cases 5 years after treatment).HCC recurrence within 2 years of treatment is defined as“early”and is generally caused by the occult intrahepatic spread of the primary neoplasm and related to the tumor burden.A recurrence that occurs after 2 years of treatment is defined as“late”and is related to de novo HCC,independent of the primary neoplasm.Early HCC recurrence has a significantly poorer prognosis and outcome than late recurrence.Different pathogenesis corresponds to different predictors of the risk of early or late recurrence.An adequate knowledge of predictive factors and recurrence risk stratification guides the therapeutic strategy and post-treatment surveillance.Patients at high risk of HCC recurrence should be referred to treatments with the lowest recurrence rate and when standardized to combined or adjuvant therapy regimens.This review aimed to expose the recurrence predictors and examine the differences between predictors of early and late recurrence.

Treatment of hepatocellular carcinoma in patients with portal vein tumor thrombosis: Beyond the known frontiers

Hepatocellular carcinoma is one of the most frequent malignant tumors worldwide:Portal vein tumor thrombosis(PVTT)occurs in about 35%-50%of patients and represents a strong negative prognostic factor,due to the increased risk of tumor spread into the bloodstream,leading to a high recurrence risk.For this reason,it is a contraindication to liver transplantation and in several prognostic scores sorafenib represents its standard of care,due to its antiangiogenetic action,although it can grant only a poor prolongation of life expectancy.Recent scientific evidences lead to consider PVTT as a complex anatomical and clinical condition,including a wide range of patients with different prognosis and new treatment possibilities according to the degree of portal system involvement,tumor biological aggressiveness,complications caused by portal hypertension,patient’s clinical features and tolerance to antineoplastic treatments.The median survival has been reported to range between 2.7 and 4 mo in absence of therapy,but it can vary from 5 mo to 5 years,thus depicting an extremely variable scenario.For this reason,it is extremely important to focus on the most adequate strategy to be applied to each group of PVTT patients.

New approaches in the treatment of hepatitis C

About 130-170 million people, is estimated to be infected with the hepatitis C virus(HCV). Chronic HCV infection is one of the leading causes of liverrelated death and in many countries it is the primaryreason for having a liver transplant. The main aim of antiviral treatment is to eradicate the virus. Until a few years ago the only treatment strategy was based on the combination of pegylated interferon and ribavirin(PEG/RBV). However, in genotypes 1 and 4 the rates of viral response did not surpass 50%, reaching up to 80% in the rest. In 2011 approval was given for the first direct acting antiviral agents(DAA), boceprevir and telaprevir, for treatment of genotype 1, in combination with traditional dual therapy. This strategy managed to increase the rates of sustained viral response(SVR) in both naive patients and in retreated patients, but with greater toxicity, interactions and cost, as well as being less safe in patients with advanced disease, in whom this treatment can trigger decompensation or even death. The recent, accelerated incorporation since 2013 of new more effective DAA, with pan-genomic properties and excellent tolerance, besides increasing the rates of SVR(even up to 100%), has also created a new scenario: shorter therapies, less toxicity and regimens free of PEG/RBV. This has enabled their almost generalised applicability in all patients. However, it should be noted that most of the scientific evidence available is based on expert opinion, case-control series, cohort studies and phase 2 and 3 trials, some with a reduced number of patients and select groups. Few data are currently available about the use of these drugs in daily clinical practice, particularly in relation to the appearance of side effects and interactions with other drugs, or their use in special populations or persons with the less common genotypes. This situation suggests the need for the generalised implementation of registries of patients receiving antiviral therapy. The main inconvenience of these new drugs is their high cost. This necessitates selection and prioritization of candidate patients to receive them, via strategies established by the various national organs, in accordance with the recommendations of scientific societies.

Gut microbiota in alcoholic liver disease: Pathogenetic role and therapeutic perspectives

Alcoholic liver disease(ALD) is the commonest cause of cirrhosis in many Western countries and it has a high rate of morbidity and mortality. The pathogenesis is characterized by complex interactions between metabolic intermediates of alcohol. Bacterial intestinal flora is itself responsible for production of endogenous ethanol through the fermentation of carbohydrates. The intestinal metabolism of alcohol produces a high concentration of toxic acetaldehyde that modifies gut permeability and microbiota equilibrium. Furthermore it causes direct hepatocyte damage. In patients who consume alcohol over a long period, there is a modification of gut microbiota and, in particular, an increment of Gram negative bacteria. This causes endotoxemia and hyperactivation of the immune system. Endotoxin is a constituent of Gram negative bacteria cell walls. Two types of receptors, cluster of differentiation 14 and Toll-like receptors-4, present on Kupffer cells, recognize endotoxins. Several studies have demonstrated the importance of gut-liver axis and new treatments have been studied in recent years to reduce progression of ALD modifying gut microbiota. It has focused attention on antibiotics, prebiotics, probiotics and synbiotics.

Hepato-cardiac disorders

Understanding the mutual relationship between the liver and the heart is important for both hepatologists and cardiologists. Hepato-cardiac diseases can be classified into heart diseases affecting the liver, liver diseases affecting the heart, and conditions affecting the heart and the liver at the same time. Differential diagnoses of liver injury are extremely important in a cardiologist's clinical practice calling for collaboration between cardiologists and hepatologists due to the many other diseases that can affect the liver and mimic haemodynamic injury. Acute and chronic heart failure may lead to acute ischemic hepatitis or chronic congestive hepatopathy. Treatment in these cases should be directed to the primary heart disease. In patients with advanced liver disease, cirrhotic cardiomyopathy may develop including hemodynamic changes, diastolic and systolic dysfunctions, reduced cardiac performance and electrophysiological abnormalities. Cardiac evaluation is important for patients with liver diseases especially before and after liver transplantation. Liver transplantation may lead to the improvement of all cardiac changes and the reversal of cirrhotic cardiomyopathy. There are systemic diseases that may affect both the liver and the heart concomitantly including congenital, metabolic and inflammatory diseases as well as alcoholism. This review highlights these hepatocardiac

Clinical expression of insulin resistance in hepatitis C and B virus-related chronic hepatitis:Differences and similarities

AIM： To investigate the prevalence of the clinical pa- rameters of insulin resistance and diabetes in patients affected by chronic hepatitis C （CHC） or chronic hepa- titis B （CHB）. METHODS： We retrospectively evaluated 852 consec- utive patients （726 CHC and 126 CriB） who had under- gone liver biopsy. We recorded age, sex, ALT, type 2 diabetes and/or metabolic syndrome （MS）, body mass index （BMI）, and apparent disease duration （ADD）. RESULTS： Age, ADD, BMI, prevalence of MS and diabetes in patients with mild/moderate liver fibrosis were significantly higher in CHC. However, the degree of steatosis and liver fibrosis evaluated in liver biop- sies did not differ between CHC and CHB patients. At multivariate analysis, age, sex, BMI, ALT and diabetes were independent risk factors for liver fibrosis in CHC, whereas only age was related to liver fibrosis in CHB. We also evaluated the association between significant steatosis （〉 30%） and age, sex, BMI, diabetes, MS and liver fibrosis. Diabetes, BMI and liver fibrosis were associated with steatosis 〉 30% in CHC, whereas only age and BMI were related to steatosis in CriB. CONCLUSION： These data may indicate that hepatitis C virus infection is a risk factor for insulin resistance.

Vitamin D deficiency in chronic liver disease

Vitamin D is an important secosteroid hormone with known effect on calcium homeostasis,but recently there is increasing recognition that vitamin D also is involved in cell proliferation and differentiation,has immunomodulatory and anti-inflammatory properties.Vitamin D deficiency has been frequently reported in many causes of chronic liver disease and has been associated with the development and evolution of non-alcoholic fatty liver disease(NAFLD)and chronic hepatitis C(CHC)virus infection.The role of vitamin D in the pathogenesis of NAFLD and CHC is not completely known,but it seems that the involvement of vitamin D in the activation and regulation of both innate and adaptive immune systems and its antiproliferative effect may explain its importance in these liver diseases.Published studies provide evidence for routine screening for hypovitaminosis D in patients with liver disease.Further prospectives studies demonstrating the impact of vitamin D replacement in NAFLD and CHC are required.

Characterization of six tumorsuppressor genes and microsatellite instability in hepatocellular carcinomain southern African blacks

AIM To analyse cumulative loss of heterozygosity (LOH) of chromosomal regions and tumor suppressor genes in hepatocellular carcinomas (HCCs) from 20 southern African blacks. METHODS p53, RB1, BRCA1, BRCA2, WT1 and E cadherin genes were analysed for LOH, and p53 gene was also analysed for the codon 249 mutation, in tumor and adjacent non tumorous liver tissues using molecular techniques and 10 polymorphic microsatellite markers. RESULTS p53 codon 249 mutation was found in 25% of the subjects, as was expected, because many patients were from Mozambique, a country with high aflatoxin B 1 exposure. LOH was found at the RB1, BRCA2 and WT1 loci in 20%(4/*!20) of the HCCs, supporting a possible role of these genes in HCC. No LOH was evident in any of the remaining genes. Reports of mutations of p53 and RB1 genes in combination, described in other populations, were not confirmed in this study. Change in microsatellite repeat number was noted at 9/*!10 microsatellite loci in different HCCs, and changes at two or more loci were detected in 15%(3/*!20) of subjects. CONCLUSION We propose that microsatellite/genomic instability may play a role in the pathogenesis of a subset of HCCs in black Africans.

Specific CD8^+ T cell response immunotherapy for hepatocellular carcinoma and viral hepatitis

Hepatocellular carcinoma (HCC), chronic hepatitis B (CHB) and chronic hepatitis C (CHC) are characterized by exhaustion of the specific CD8+ T cell response. This process involves enhancement of negative co-stimulatory molecules, such as programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen-4 (CTLA-4), 2B4, Tim-3, CD160 and LAG-3, which is linked to intrahepatic overexpression of some of the cognate ligands, such as PD-L1, on antigen presenting cells and thereby favouring a tolerogenic environment. Therapies that disrupt these negative signalling mechanisms represent promising therapeutic tools with the potential to restore reactivity of the specific CD8+ T cell response. In this review we discuss the impressive in vitro and in vivo results that have been recently achieved in HCC, CHB and CHC by blocking these negative receptors with monoclonal antibodies against these immune checkpoint modulators. The article mainly focuses on the role of CTLA-4 and PD-1 blocking monoclonal antibodies, the first ones to have reached clinical practice. The humanized monoclonal antibodies against CTLA-4 (tremelimumab and ipilimumab) and PD-1 (nivolumab and pembrolizumab) have yielded good results in testing of HCC and chronic viral hepatitis patients. Trelimumab, in particular, has shown a significant increase in the time to progression in HCC, while nivolumab has shown a remarkable effect on hepatitis C viral load reduction. The research on the role of ipilimumab, nivolumab and pembrolizumab on HCC is currently underway.