Prevalence of hepatocellular carcinoma in alpha-1-antitrypsin deficiency

AAT: does it have a place in acute leukemia?

Aim: In this study, the authors aimed to investigate the change of AAT, its effect on the response to induction and its effects on the treatment process in acute myeloid leukemia and acute lymphoblastic leukemia patients. Materials & methods: This study included 94 patients who were hospitalized and followed up in Istanbul Training and Research Hospital, Hematology Clinic, between October 2019 and December 2021. Results: Patients with a complete response had higher serum AAT levels than those with a non-complete response (p < 0.05). The mean serum AAT level was found to be significantly higher in patients without Gram-positive growth than in patients with Gram-positive growth. Conclusion: It can be thought that AAT can play a role during the course of acute leukemia management.

Association of Alpha-1 Antitrypsin Pi*Z Allele Frequency and Progressive Liver Fibrosis in Two Chronic Hepatitis C Cohorts

(1) Background: The inherited alpha-1 antitrypsin (A1AT) deficiency variant 'Pi*Z' emerged as a genetic modifier of chronic liver disease. Controversial data exist on the relevance of heterozygous Pi*Z carriage ('Pi*MZ' genotype) as an additional risk factor in patients with chronic viral hepatitis C to develop progressive liver fibrosis. (2) Methods: Two prospectively recruited cohorts totaling 572 patients with therapy-naïve chronic viral hepatitis C (HCV) were analyzed. The Frankfurt cohort included 337 patients and a second cohort from Leipzig included 235 patients. The stage of liver fibrosis was assessed by liver biopsy, AST-to-platelet ratio index (APRI) score and Fibrosis-4 (FIB-4) score (Frankfurt) as well as liver stiffness measurement (LSM) via transient elastography (Leipzig). All patients were genotyped for the Pi*Z variant (rs28929474) of the SERPINA1 gene. (3) Results: In the Frankfurt cohort, 16/337 (4.7%) patients carried the heterozygous Pi*Z allele while 10/235 (4.3%) in the Leipzig cohort were Pi*Z carriers. In both cohorts, there was no higher proportion of Pi*Z heterozygosity in patients with cirrhosis compared to patients without cirrhosis or patients with cirrhosis vs. no liver fibrosis. Accordingly, Pi*Z frequency was not different in histological or serological stages of liver fibrosis (F0-F4) and showed no clear association with LSM. (4) Conclusions: Evaluation in two representative HCV cohorts does not indicate Pi*Z heterozygosity as a clinically relevant disease modifier in chronic HCV infection. However, validation in even larger cohorts with longitudinal follow-up is warranted.

Hepatocellular Carcinoma in Patients Without Cirrhosis: The Fibrosis Stage Distribution, Characteristics and Survival

BACKGROUND

The data on hepatocellular carcinoma (HCC) patients without liver cirrhosis is scarce.

AIMS

To study the epidemiology, underlying etiology and fibrosis distribution in noncirrhotic HCC and compare the survival outcomes to cirrhotic HCC.

METHODS

We conducted a retrospective study including all adult patients diagnosed with HCC at two US tertiary academic centers from 2000 to 2015. Univariable and multivariable Cox regression analyses were performed to evaluate the variables associated with patient survival.

RESULTS

Two thousand two hundred and thirty-seven HCC patients were included in the final analysis, of which, 13% had no liver cirrhosis. The most common underlying liver disease in non-cirrhotic patients was cryptogenic cause (40%), followed by nonalcoholic fatty liver disease (NAFLD) (25.2%) and hepatitis C (19%). The percentage of F0-F1, F2, and F3 was 72%, 17%, and 11% (cryptogenic cause); 69%, 12%, and 19% (NAFLD); 50%, 17%, and 33% (alcohol); 33%, 39%, and 28% (hepatitis B); 20%, 40%, and 40% (hemochromatosis); and 12%, 40%, and 48% (hepatitis C), respectively. In non-cirrhotic compared to cirrhotic patients, the tumor was more likely to be larger and fell outside Milan criteria (all p < 0.001). Cirrhotic patients had significant shorter survival than non-cirrhotic patients (p < 0.001). On the multivariable analysis, having liver cirrhosis (HR 1.48; 1.21-1.82, p < 0.001), combined viral hepatitis and alcohol use (HR 1.51; 1.23-1.88, p < 0.001), morbid obesity (HR 1.31; 1.01-1.69, p = 0.040) and underweight (HR 2.06; 1.27-3.34, p = 0.004) were associated with worse patient survival.

CONCLUSIONS

The fibrosis distribution in non-cirrhotic HCC differed among each etiology of liver diseases. Despite more advanced HCC, patients without cirrhosis had significantly longer survival than those with cirrhosis.

Evaluation of Alpha 1-Antitrypsin for the Early Diagnosis of Colorectal Cancer

Previous proteomic studies have identified alpha 1-antitrypsin (A1AT) as a potential serum biomarker for colorectal cancer (CRC). In this case-control study, we evaluated plasma A1AT concentration and activity as a biomarker for the early diagnosis of colorectal cancer in a group of 113 sporadic CRC patients. We also analyzed A1AT gene promoter methylation, and genotypes in this group of CRC patients. The plasma A1AT and CEA concentrations were measured using the nephelometric and ELISA methods, respectively. A1AT activity was determined by Trypsin Inhibitor Capacity assay. The genomic DNA from blood samples were subjected to Z and S genotype analysis using PCR-RFLP method and the gene promoter methylation in tumors and their adjacent normal tissues was determined by methylation specific-PCR assay. The plasma levels of A1AT and CEA in patients (median, 2.3 g/L and 5.96 ng/ml, respectively) were significantly higher than those in healthy controls (medians, 1.43 g/L and 2.57 ng/ml, respectively) (p = 0.0001). The plasma A1AT activity and concentrations were positively correlated with the tumor stage and well-discriminated between early and advanced stages. The A1AT activity in plasma was the most useful marker for CRC diagnosis (median 4.8 mmol/min/ml in cases vs 1.91 mmol/min/ml in controls, p = 0.0001). No deficient Z or S alleles of A1AT was observed in patients' genotype and the gene promoter tends to be more methylated in normal mucosa than in tumor tissues. We conclude that plasma A1AT activity has better sensitivity and specificity than CEA measurement for the early detection of CRC. Promoter demethylation might play a role in increasing plasma A1AT levels in CRC patients.

Assessment of liver fibrosis by transient elastography (Fibroscan®) in patients with A1AT deficiency

BACKGROUND

Alpha-1-antitrypsin deficiency (A1ATD) is a common genetic condition which predisposes to emphysema and liver disorders. It is estimated that 10-15% of homozygous individuals for the Z allele (PiZZ) may develop liver fibrosis. The optimal modalities to detect liver disease in PiZZ adult patients need to be defined. The aim of this prospective study was to perform a systematic non-invasive evaluation of the liver fibrosis by elastometry using Fibroscan^® in a cohort of A1ATD patients with emphysema.

METHODS

Patients followed in our respiratory unit were enrolled in this prospective study and underwent on the same day a physical examination, a biochemical profiling, an abdominal ultrasound (US) and a Fibroscan^®.

RESULTS

Twenty-nine PiZZ adults (19 male) were included. Median age was 50.4 yrs (21.5-67.2). Median serum A1AT level was 0.20 g/L (0.15-0.33). Liver Function Tests (LFT) were not normal in 2 patients and US was abnormal in 6 patients. Two patients had both abdnormal LFT and US. Fibroscan^® was technically feasible in 28/29 (97%) patients. Median liver stiffness was 4.5 kPa (2.8-32.8), and was > 7.2 kPa in 5/28 (18%) and > 14 kPa in 2/28 (7%) patients. Liver stiffness was increased in 2/2 (100%) patients with abnormal LFT and US, in 1/4 (25%) with abnormal LFT or US and in 2/22 (10%) patients with normal LFT and US.

CONCLUSIONS

Fibroscan^® is an easy and repeatable tool which can be used in PiZZ patients to screen for the presence of significant liver fibrosis and to identify patients at higher risk to develop liver complications in the future and who may benefit from a closer surveillance.

The Role of Diagnosis and Treatment of Underlying Liver Disease for the Prognosis of Primary Liver Cancer

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. Underlying chronic liver disease has been associated with an increased risk of developing HCC. This study is a review of the current literature regarding the diagnosis, prognostic significance, and role of treating underlying liver disease in patients who are at risk of primary liver cancer. Relevant peer review of the English literature between 1980 and 2017 within PubMed and the Cochrane library was conducted for scientific content on current advances in managing chronic liver diseases and the development of hepatocellular carcinoma. Hepatitis C virus, hepatitis B virus (HBV), nonalcoholic steatohepatitis, autoimmune hepatitis, hereditary hemochromatosis, Wilson disease, primary biliary cirrhosis, α 1-antitrypsin deficiency, and certain drugs lead to an increased risk of developing HCC. Patients with underlying liver disease have an increased incidence of HCC. Hepatitis C virus, HBV, and hemochromatosis can directly lead to HCC without the presence of cirrhosis, while HCC related to other underlying liver diseases occurs in patients with cirrhosis. Treating the underlying liver disease and reducing the progression to cirrhosis should lead to a decreased incidence of HCC.

Systematic review: the natural history of alpha-1 antitrypsin deficiency, and associated liver disease

BACKGROUND

Alpha-1 antitrypsin deficiency (AATD) is estimated to affect three million people worldwide. It causes liver disease in a proportion of carriers of the PiS and PiZ allele due to the formation and retention of polymers within the endoplasmic reticulum of hepatocytes. The reason for this selective penetrance is not known. Although clinical trials are underway, liver transplantation is the only effective treatment for liver disease due to AATD.

AIMS

To report the prevalence and natural history of liver disease among individuals with AATD, and assess the outcomes of liver transplantation through systematic review.

METHODS

A comprehensive search was conducted across multiple databases. Two independent authors selected the articles and assessed bias using the Newcastle-Ottawa Scale. Data were pooled for analysis, where comparable outcomes were reported.

RESULTS

Thirty-five studies were identified related to disease progression and 12 for the treatment of AATD. Seven per cent of children were reported to develop liver cirrhosis, with 16.5% of individuals presenting in childhood requiring liver transplantation. Of those surviving to adulthood, 10.5% had liver cirrhosis and 14.7% required transplantation. Liver transplantation was the only effective treatment reported and outcomes compare favourably to other indications, with 5-year survival reported as over 90% in children and over 80% in adults.

DISCUSSION

The clinical course of liver disease in individuals with AATD remains poorly understood, but affects about 10% of those with AATD. More research is required to identify those patients at risk of developing liver disease at an early stage, and to provide alternative treatments to liver transplantation.

Alpha-1 antitrypsin deficiency and the risk of hepatocellular carcinoma in end-stage liver disease

AIM: To evaluate the association between alpha-1 antitrypsin deficiency (A1ATD) and hepatocellular carcinoma (HCC) in patients with end-stage liver disease (ESLD).

METHODS: Patients with cirrhosis and ESLD referred to the Cleveland Clinic Foundation for liver transplantation between 2003 and 2014 were included in the study (N = 675). ESLD was defined as having histological features of cirrhosis and/or radiological evidence of cirrhosis in the context of portal hypertension (ascites, variceal bleeding, thrombocytopenia, or hepatic encephalopathy). A1ATD was diagnosed using phenotype characterization (MZ or ZZ), liver biopsy detection of PAS-positive diastase-resistant (PAS+) globules, or both. Patients with other causes of liver diseases such as hepatitis C virus (HCV), alcoholic liver disease and non-alcoholic steatohepatitis (NASH) or NASH were also included in the study. HCC was diagnosed by using imaging modalities, biopsy findings, or explanted liver inspection. Follow-up time was defined as the number of years from the diagnosis of cirrhosis to the diagnosis of hepatocellular carcinoma, or from the diagnosis of cirrhosis to the last follow up visit. The rate of HCC was assessed using time-to-interval analysis for interval censored data.

RESULTS: This study included 675 patients. 7% of subjects had A1ATD (n = 47). Out of all subjects who did not have A1ATD, 46% had HCV, 17% had alcoholic liver disease, 19% had NASH and 18% had another primary diagnosis. Of the 47 subjects with A1ATD, 15 had a primary diagnosis of A1ATD (PI*ZZ phenotype and PAS+ globules), 8 had a PI*MZ phenotype alone, 14 had PAS+ alone, and 10 had both the PI*MZ phenotype and PAS+. Median follow-up time was 3.4 (25^th, 75^th percentiles: 1, 5.2) years. The overall rate of hepatocellular carcinoma in all subjects was 29% (n = 199). In the A1ATD group, the incidence rate of HCC was 8.5% compared to 31% in the group of patients with other causes of cirrhosis (P = 0.001). Patients with ESLD due to A1ATD had the lowest yearly cumulative rate of hepatocellular carcinoma at 0.88% per year compared to 2.7% for those with HCV cirrhosis, 1.5% in patients with NASH and 0.9% in alcohol-induced liver disease (P < 0.001).

CONCLUSION: Within this group of patients with ESLD, there was no significant association between A1ATD and increased risk of HCC.

Alpha-1-antitrypsin in pathogenesis of hepatocellular carcinoma

CONTEXT

Alpha-1-antitrypsin (A1AT) is the most abundant liver-derived, highly polymorphic, glycoprotein in plasma. Hereditary deficiency of alpha-1-antitrypsin in plasma (A1ATD) is a consequence of accumulation of polymers of A1AT mutants in endoplasmic reticulum of hepatocytes and other A1AT-producing cells. One of the clinical manifestations of A1ATD is liver disease in childhood and cirrhosis and/or hepatocellular carcinoma (HCC) in adulthood. Epidemiology and pathophysiology of liver failure in early childhood caused by A1ATD are well known, but the association with hepatocellular carcinoma is not clarified. The aim of this article is to review different aspects of association between A1AT variants and hepatocellular carcinoma, with emphasis on the epidemiology and molecular pathogenesis. The significance of A1AT as a biomarker in the diagnosis of HCC is also discussed.

EVIDENCE ACQUISITIONS

Search for relevant articles were performed through Pub Med, HighWire, and Science Direct using the keywords "alpha-1-antitrypsin", "liver diseases", "hepatocellular carcinoma", "SERPINA1". Articles published until 2011 were reviewed.

RESULTS

Epidemiology studies revealed that severe A1ATD is a significant risk factor for cirrhosis and HCC unrelated to the presence of HBV or HCV infections. However, predisposition to HCC in moderate A1ATD is rare, and probably happens in combination with HBV and/or HCV infections or other unknown risk factors. It is assumed that accumulation of polymers of A1ATD variants in endoplasmic reticulum of hepatocytes leads to damage of hepatocytes by gain-of-function mechanism. Also, increased level of A1AT was recognized as diagnostic and prognostic marker of HCC.

CONCLUSIONS

Clarification of a carcinogenic role for A1ATD and identification of proinflammatory or some still unknown factors that lead to increased susceptibility to HCC associated with A1ATD may contribute to a better understanding of hepatic carcinogenesis and to the development of new drugs.

Oxidative stress contributes to liver damage in a murine model of alpha-1-antitrypsin deficiency

Alpha-1-antitrypsin deficiency is a genetic disorder resulting in the expression of misfolded mutant protein that can polymerize and accumulate in hepatocytes, leading to liver disease in some individuals. Transgenic PiZ mice are a well-characterized model, which express human alpha-1-antitrypsin mutant Z protein (ATZ protein) and faithfully recapitulate the human liver disease. Liver tissue expressing alpha-1-antitrypsin mutant Z protein exhibits inflammation, injury and replacement of damaged cells. Fibrosis and hepatocellular carcinoma (HCC) develop in aging PiZ mice. In this study, microarray analysis was performed comparing young PiZ (ZY) mice to wild-type (WY), and indicated that there were alterations in gene expression levels that could influence a number of pathways leading to liver disease. Redox-regulating genes were up-regulated in ZY tissue, including carbonyl reductase 3 (CBR3), glutathione S-transferase alpha 1 + 2 (GSTA(1 + 2)) and glutathione S-transferase mu 3 (GSTM3). We hypothesized that oxidative stress could develop in Z mouse liver, contributing to tissue damage and disease progression with age. The results of biochemical analysis of PiZ mouse liver revealed that higher levels of reactive oxygen species (ROS) and a more oxidized, cellular redox state occurred in liver tissue from ZY mice than WY. ZY mice showed little evidence of oxidative cellular damage as assessed by protein carbonylation levels, malondialdehyde levels and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8oxodG) staining. Aging liver tissue from PiZ older mice (ZO) had elevated ROS, generally lower levels of antioxidant enzymes than younger mice and evidence of cellular damage. These data indicate that oxidative stress is a contributing factor in the development of liver disease in this model of alpha-1-antitrypsin deficiency.

Sustained miRNA-mediated knockdown of mutant AAT with simultaneous augmentation of wild-type AAT has minimal effect on global liver miRNA profiles

α-1 antitrypsin (AAT) deficiency can exhibit two pathologic states: a lung disease that is primarily due to the loss of AAT's antiprotease function, and a liver disease resulting from a toxic gain-of-function of the PiZ-AAT (Z-AAT) mutant protein. We have developed several recombinant adeno-associated virus (rAAV) vectors that incorporate microRNA (miRNA) sequences targeting the AAT gene while also driving the expression of miRNA-resistant wild-type AAT-PiM (M-AAT) gene, thus achieving concomitant Z-AAT knockdown in the liver and increased expression of M-AAT. Transgenic mice expressing the human PiZ allele treated with dual-function rAAV9 vectors showed that serum PiZ was stably and persistently reduced by an average of 80%. Treated animals showed knockdown of Z-AAT in liver and serum with concomitant increased serum M-AAT as determined by allele-specific enzyme-linked immunosorbent assays (ELISAs). In addition, decreased globular accumulation of misfolded Z-AAT in hepatocytes and a reduction in inflammatory infiltrates in the liver was observed. Results from microarray studies demonstrate that endogenous miRNAs were minimally affected by this treatment. These data suggests that miRNA mediated knockdown does not saturate the miRNA pathway as has been seen with viral vector expression of short hairpin RNAs (shRNAs). This safe dual-therapy approach can be applied to other disorders such as amyotrophic lateral sclerosis, Huntington disease, cerebral ataxia, and optic atrophies.

Characteristics of hepatocellular carcinoma in a murine model of alpha-1-antitrypsin deficiency

AIM

Individuals with homozygous (ZZ) alpha-1-antitrypsin (alpha1AT) deficiency are at an increased risk for liver damage, cirrhosis and hepatocellular carcinoma (HCC). The transgenic PiZ mouse, expressing the human alpha1AT mutant Z gene, is a valuable model for this disease. We studied PiZ mice in order to identify and characterize mechanisms involved in the development of HCC.

METHODS

Tumor incidence and histology were studied, gene expression levels were surveyed with microarrays, RNA quantified with quantitative real time polymerase chain reaction and protein levels determined with immunoblots and immunohistochemistry.

RESULTS

By 16-19 months of age, approximately 69% of the PiZ mice had developed tumors. HCC was present with no evidence of benign adenomas as pre-cancerous lesions. Tumors showed abnormal mitochondria, variable levels of steatosis, globular inclusions of alpha1AT mutant Z protein and metastases. PiZ mice that subsequently developed liver tumors had higher serum levels of alpha1AT mutant Z protein than those that did not develop tumors. Cyclin D1, a cell cycle protein, was upregulated in PiZ livers without tumors compared to Wt. cFOS, a component of AP-1 that may be involved in transforming cells and MCAM, an adhesion molecule likely involved in tumorigenesis and metastases, were elevated in tumors compared with livers without tumors.

CONCLUSION

In the PiZ model, many of the histological characteristics of HCC recapitulated features seen in human HCC, whether from individuals with homozygous ZZ liver disease or from unrelated causes in individuals that were not homozygous ZZ. The accumulation of mutant Z protein altered the regulation of several genes driving proliferation and tumorigenesis.

Polymorphism of alpha-1-antitrypsin in hematological malignancies

Alpha-1-antitrypsin (AAT) or serine protease inhibitor A1 (SERPINA1) is an important serine protease inhibitor in humans. The main physiological role of AAT is to inhibit neutrophil elastase (NE) released from triggered neutrophils, with an additional lesser role in the defense against damage inflicted by other serine proteases, such as cathepsin G and proteinase 3. Although there is a reported association between AAT polymorphism and different types of cancer, this association with hematological malignancies (HM) is, as yet, unknown. We identified AAT phenotypes by isoelectric focusing (in the pH 4.2-4.9 range) in 151 serum samples from patients with HM (Hodgkins lymphomas, non-Hodgkins lymphomas and malignant monoclonal gammopathies). Healthy blood-donors constituted the control group (n = 272). The evaluated population of patients as well as the control group, were at Hardy-Weinberg equilibrium for the AAT gene (χ² = 4.42, d.f.11, p = 0.96 and χ² = 4.71, d.f.11, p = 0.97, respectively). There was no difference in the frequency of deficient AAT alleles (Pi Z and Pi S) between patients and control. However, we found a significantly higher frequency of PiM1M1 homozygote and PiM1 allele in HM patients than in control (for phenotype: f = 0.5166 and 0.4118 respectively, p = 0.037; for allele: f = 0.7020 and 0.6360 respectively, p = 0.05). In addition, PiM homozygotes in HM-patients were more numerous than in controls (59% and 48%, respectively, p = 0.044). PiM1 alleles and PiM1 homozygotes are both associated with hematological malignancies, although this is considered a functionally normal AAT variant.

Z and Mmalton-1-antitrypsin deficiency-associated hepatocellular carcinoma: a genetic study

BACKGROUND

The histological hallmark of alpha-1-antitrypsin deficiency (AATD) is the presence of periodic acid-Schiff diastase (PASD)-resistant positive globules in hepatocytes, with a heterogeneous distribution. It is noteworthy that hepatocellular carcinoma (HCC) arises specifically from the AAT-negative areas but the reason for this remains unclear.

AIM

To determine whether the different distribution of AAT globules within neoplastic and non-neoplastic hepatocytes is the result of a self-induced correction of the genetic defect.

PATIENTS AND METHODS

Two HCV-positive patients with AATD-associated HCC were studied. One patient harboured a compound heterozygous PiSZ genotype whereas the other showed the rarer PiMMmalton in heterozygosity. In both cases, neoplastic hepatocytes appeared globule devoid, while non-neoplastic hepatocytes showed intracytoplasmic accumulation of PASD-positive globules. Laser-assisted microdissection was used to assess a genotype/phenotype correlation in single liver cells from HCC and from non-neoplastic hepatocytes.

RESULTS

Direct sequencing of DNA purified from globule-devoid and globule-filled hepatocytes demonstrated that all liver cells carried the same mutant genetic background.

CONCLUSION

Our findings indicate that (i) both variants of HCC arising in AAT deficiency (Z and Mmalton) do not accumulate the mutant protein and (ii) the different phenotypic appearance of hepatocytes is not the result of a retromutation during neoplastic transformation, but other mechanisms should be investigated.

FXR: a metabolic regulator and cell protector

Farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily of ligand-activated transcription factors. As a metabolic regulator, FXR plays key roles in bile acid, cholesterol, lipid, and glucose metabolism. Therefore, FXR is a potential drug target for a number of metabolic disorders, especially those related to the metabolic syndrome. More recently, our group and others have extended the functions of FXR to more than metabolic regulation, which include anti-bacterial growth in intestine, liver regeneration, and hepatocarcinogenesis. These new findings suggest that FXR has much broader roles than previously thought, and also highlight FXR as a drug target for multiple diseases. This review summarizes the basic information of FXR but focuses on its new functions.

Indomethacin increases liver damage in a murine model of liver injury from alpha-1-antitrypsin deficiency

Homozygous (PIZZ) alpha-1-antitrypsin (alpha(1)-AT) deficiency is associated with the development of liver damage in children as well as chronic liver injury and hepatocellular carcinoma in adults. The alpha(1)-AT mutant Z gene encodes a mutant protein that accumulates in the endoplasmic reticulum of hepatocytes rather than being secreted appropriately into serum. Liver injury is caused by the accumulation of alpha(1)-AT mutant Z protein in hepatocytes, which triggers downstream intracellular injury pathways. However, development of clinical liver disease among PIZZ homozygotes is highly variable, suggesting other genetic or environmental factors contribute to liver injury. In this study, we tested whether nonsteroidal anti-inflammatory drugs (NSAIDs) could be a comorbid factor in the development of liver injury in alpha(1)-AT deficiency using the PiZ mouse. This mouse model is transgenic for the mutant Z allele of the human alpha(1)-AT gene, in which alpha(1)-ATZ expression is regulated by the human promoter regulatory sequences. Our results showed that administration of indomethacin to PiZ mice resulted in increased hepatic injury, indicated by increased hepatocellular proliferation and increased activation of caspase 9. This indomethacin-induced injury was associated with activation of IL-6-STAT3 signaling, increased expression of alpha(1)-AT mRNA, and greater accumulation of mutant polymerized alpha(1)-ATZ protein in livers of indomethacin-treated PiZ mice compared to vehicle-treated PiZ animals. In conclusion, environmental factors, such as exogenous medication administration, can significantly potentiate the liver injury associated with alpha(1)-ATZ hepatic accumulation; NSAIDs may be especially injurious to patients with alpha(1)-AT deficiency, possibly by increasing the expression and accumulation of the hepatotoxic mutant protein.

Occult viral hepatitis and noncirrhotic hepatocellular carcinoma

The achievement of a sustained virologic response to hepatitis C antiviral therapy represents a milestone occurrence that many tout as a cure. Recent studies, however, have found trace HCV viral material both among sustained responders and in patients with chronic liver disease who are HCV RNA negative, suggesting the entity of occult hepatitis C. As a body of literature emerges on the pathogenic role of occult hepatitis B, little is known of the potential importance of occult type C hepatitis. Specifically, occult hepatitis B has been strongly implicated as a culprit that facilitates the development of hepatocellular carcinoma, typically in the background of cirrhosis. Those cancers that develop in noncirrhotic livers, an especially rare entity in the West, usually occur in the setting of smoldering liver injury, often with some degree of fibrosis. The role of multiple hepatotoxins acting in concert to potentiate hepatic carcinogenicity has become increasingly recognized, including viral coinfection. The finding of occult hepatitis B in noncirrhotic hepatocellular carcinomas among patients with hepatitis C who achieved antiviral sustained virologic response raises provocative theories regarding the natural history of both of these viral hepatitis agents.

Screening tests for hepatocellular carcinoma

The incidence of hepatocellular carcinoma (HCC) is rising throughout the world. HCC meets the criteria for which a disease benefits from screening or surveillance: it is an important health problem; those with cirrhosis are the targets for surveillance; there is acceptable treatment if diagnosed early; surveillance using alpha-fetoprotein and ultrasound has been shown to be cost effective; surveillance is widely implemented by health care professionals and accepted by patients; standardized recall procedures exists; and the screening tests must achieve an acceptable level of accuracy in the population undergoing screening. The latter point is the main limitation of surveillance for HCC. In this review we will discuss the currently available tests for the surveillance of HCC.

Screening for hepatocellular carcinoma

There is currently no evidence that screening patients at risk for hepatocellular carcinoma reduces mortality from the disease. Nonetheless, screening is widely practiced. Screening is a process that includes selecting patients, applying screening tests, deciding on recall policies, and subsequently proving or disproving the presence of cancer. The literature on screening for hepatocellular carcinoma is confusing at best, and does not adequately consider the many biases that result from uncontrolled and retrospective studies. Nonetheless, screening can be justified because it is likely that mortality is decreased by adequate treatment of small cancers, particularly in the era of liver transplantation. False-positive screening test results are common. Once an abnormal screening result is obtained there is little guidance from the literature as to how patients should be investigated further, nor about how to determine whether the screening test result was a false-positive. This should at minimum include short interval follow-up with CT scans and MRI's.

Hepatocellular carcinoma in cirrhosis: incidence and risk factors

Emerging data indicate that the mortality rate of hepatocellular carcinoma (HCC) associated with cirrhosis is rising in some developed countries, whereas mortality from non-HCC complications of cirrhosis is decreasing or is stable. Cohort studies indicate that HCC is currently the major cause of liver-related death in patients with compensated cirrhosis. Hepatitis C virus (HCV) infection is associated with the highest HCC incidence in persons with cirrhosis, occurring twice as commonly in Japan than in the West (5-year cumulative incidence, 30% and 17%, respectively), followed by hereditary hemochromatosis (5-year cumulative incidence, 21%). In hepatitis B virus (HBV)-related cirrhosis, the 5-year cumulative HCC risk is 15% in high endemic areas and 10% in the West. In the absence of HCV and HBV infection, the HCC incidence is lower in alcoholic cirrhotics (5-year cumulative risk, 8%) and subjects with advanced biliary cirrhosis (5-year cumulative risk, 4%). There are limited data on HCC risk in cirrhosis of other causes. Older age, male sex, severity of compensated cirrhosis at presentation, and sustained activity of liver disease are important predictors of HCC, independent of etiology of cirrhosis. In viral-related cirrhosis, HBV/HCV and HBV/HDV coinfections increase the HCC risk (2- to 6-fold relative to each infection alone) as does alcohol abuse (2- to 4-fold relative to alcohol abstinence). Sustained reduction of HBV replication lowers the risk of HCC in HBV-related cirrhosis. Further studies are needed to investigate other viral factors (eg, HBV genotype/mutant, occult HBV, HIV coinfection) and preventable or treatable comorbidities (eg, obesity, diabetes) in the HCC risk in cirrhosis.

Role of imbalance between neutrophil elastase and alpha 1-antitrypsin in cancer development and progression

Neutrophil elastase and alpha 1-antitrypsin are a pair of protease and protease inhibitor counterparts. The imbalance between the two counterparts is generally thought to cause tissue damage, which could create a favourable tissue environment for carcinogens and tumour progression. Laboratory research and clinical findings have indicated that a deficiency in alpha1-antitrypsin is associated with increased risk of liver cancer, bladder cancer, gall bladder cancer, malignant lymphoma, and lung cancer. Conversely, raised concentrations of neutrophil elastase might promote the development, invasion, and metastasis of many cancers. Several mechanisms of carcinogenesis have been postulated. Excess neutrophil elastase might facilitate cancer development by causing tissue damage and air trapping, which foster longer carcinogen exposure, might promote cancer progression by degrading the intercellular matrix barrier, and might directly lead to cancer development through the tumour-necrosis-factor signalling pathway.

Analyses of hepatocellular proliferation in a mouse model of alpha-1-antitrypsin deficiency

alpha-1-Antitrypsin (alpha1-AT) deficiency is the most common cause of metabolic pediatric liver disease. Hepatocellular injury is caused by toxicity of the mutant alpha-1-antitrypsin Z (alpha1-ATZ) molecule retained within hepatocytes. In these studies, we used the PiZ transgenic mouse model of alpha1-AT deficiency to examine hepatocellular proliferation in response to chronic liver injury resulting from this metabolic disease. The results showed increased hepatocellular proliferation and caspase 9 activation in male PiZ mice compared with female PiZ and wild-type mice. Hepatic alpha1-AT mRNA and protein expression also were increased in male PiZ mice, suggesting that greater hepatocellular proliferation and caspase activation in males results from increased hepatotoxicity associated with greater intracellular alpha1-ATZ accumulation. Testosterone treatment of female PiZ mice increased alpha1-ATZ expression and hepatocellular proliferation to a level comparable with that in males. In PiZ mice, hepatocytes devoid of intracellular alpha1-AT globules had a proliferative advantage compared with globule-containing hepatocytes. However, this advantage is relative because both globule-containing and globule-devoid hepatocytes exhibited comparable proliferation after partial hepatectomy. In conclusion, these data indicate that intracellular retention of mutant alpha1-ATZ is associated with a regenerative stimulus leading to increased hepatocellular proliferation, that gender-specific signals influence the degree of alpha1-AT expression and associated hepatic injury, and that hepatocytes devoid of alpha1-ATZ have a proliferative advantage over cells that accumulate the mutant protein. This selective proliferation suggests that hepatocellular transplantation may be applicable for treatment of this and other slowly progressive metabolic liver diseases.

Hepatocellular kinetics and the expression of growth hormone (GH) in the livers and liver tumours of GH-transgenic mice

Although it is well known that transgenic mice that overexpress growth hormone (GH) frequently develop liver tumours, the precise nature of the relationship between the overexpression of GH and hepatocarcinogenesis is not clear. The current study was designed to investigate the relationship between the expression of the GH transgene and changes in hepatocyte morphology and kinetics, prior to and during hepatocarcinogenesis in GH-transgenic mice. In young mice (1-month-old) prior to tumour development, GH protein, as detected by immunohistochemistry, was observed in the cytoplasm of essentially all hepatocytes. In liver tissues of older animals, apoptotic cells and hypertrophic hepatocytes did not express immunoreactive GH, even though GH was expressed strongly in the smaller hepatocytes. A relatively high proportion of large dysplastic hepatocytes (>50 microm) were apoptotic (TUNEL positive), whereas smaller hepatocytes featured more prominently in the proliferative phase, as measured by BrdU incorporation. GH expression in tumour tissue, as detected by immunohistochemistry, was often variable and generally decreased with tumour development. Northern blot analysis showed that equivalent levels of GH mRNA were present in tumour tissue and adjacent liver. However, there was no clear trend when the levels of GH mRNA extracted from adenoma, and hepatocellular carcinoma, were compared. These observations help clarify some of the mechanisms by which GH promotes hepatocarcinogenesis in GH-transgenic mice.

Serum alpha-fetoprotein for diagnosis of hepatocellular carcinoma in patients with chronic liver disease: influence of HBsAg and anti-HCV status

BACKGROUND

It is not established whether virological status affects the efficiency of alpha-fetoprotein (AFP) as a hepatocellular carcinoma (HCC) marker among patients with chronic liver disease (CLD).

METHODS

We enrolled in a case-control study 170 HCC and 170 CLD patients, matched for age, sex, CLD and HBsAg/anti-HCV status. The AFP sensitivity, specificity, positive (PPV) and negative (NPV) predictive values were calculated. PPV and NPV were evaluated for three additional HCC prevalences (5, 10, and 20%).

RESULTS

The best discriminating AFP value was 16 ng/ml. A value of 20 ng/ml (above which investigations for HCC are recommended) had equivalent sensitivity (60.0 vs. 62.4%) and specificity (90.6 vs. 89.4%). PPV of 20 ng/ml was 84.6% but decreased to 25.1% at 5% tumor prevalence. NPV was 69.4% and rose to 97.7% at 5% prevalence. In the different groups of infected patients PPV ranged from 80.0 to 90.9%, falling to 17.4-34.5% at 5% prevalence. In noninfected patients PPV was 100% at any HCC prevalence. NPV ranged from 59.0 to 73.0%, reaching 96.5-98.1% at 5% prevalence.

CONCLUSIONS

In CLD patients, AFP monitoring misses many HCCs and inappropriately arouses suspicion of malignancy in many patients. Its usefulness is barely affected by the infection responsible for CLD. An AFP elevation could be more indicative of HCC in non-infected patients.

Is heterozygous alpha-1-antitrypsin deficiency type PIZ a risk factor for primary liver carcinoma?

BACKGROUND

It is well known that homozygotes with alpha-1-antitrypsin deficiency type PiZ are associated with an increased risk of chronic liver disease and liver carcinoma. The aim of this study was to determine whether heterozygous PiZ status is a risk factor for liver carcinoma development.

METHODS

Three hundred seventeen consecutive primary liver carcinomas and the tumor-bearing liver tissue (tumor series) from adult patients were screened immunohistochemically for hepatocellular PiZ deposits. Liver specimens from 1663 consecutive adult patients (biopsy series) and liver tissue from 1030 consecutive adult autopsies (autopsy series) served as controls. The zygosity status of alpha-1-antitrypsin was verified by analysis of single strand conformational polymorphism and by sequencing DNA extracted from paraffin embedded tissue.

RESULTS

The PiZ frequency in the tumor series (5.99%) was significantly higher than in the biopsy series (3.43%) or the autopsy series (1.84%). Cholangiocarcinomas and/or combined hepatocholangiocarcinomas were seen significantly more frequently in PiZ-associated liver carcinomas (57.9%) than in non-PiZ-associated carcinomas (27.2%). Cirrhosis was found in only 3 of the 19 PiZ-associated carcinomas. The remaining 16 livers showed varying stages of fibrosis or normal tissue. All nine cases with PiZ-associated liver carcinoma suitable for genetic analysis showed heterozygous PiZ mutations.

CONCLUSIONS

Heterozygotes of type PiZ are associated with an increased risk of primary liver carcinoma. PiZ-associated carcinoma may develop in noncirrhotic liver tissue and without concurrent liver disease, and is frequently characterized by cholangiocellular differentiation. The site specific antibody ATZ11 is a reliable morphologic tool for detecting PiZ individuals.

Liver carcinoma in PiZ alpha-1-antitrypsin deficiency

One hundred sixty-four consecutive cases of primary liver carcinoma were evaluated for tumor type, (i.e., hepatocellular carcinoma [HCC], cholangiocarcinoma [CC], and combined hepatocholangiocarcinoma [CHCC]), and for signs of alpha-1-antitrypsin deficiency (AATD) in the surrounding liver tissue. Hepatocellular globular alpha-1-antitrypsin deposits, as detected by a monoclonal antibody to the mutant PiZ alpha-1-antitrypsin (AAT), were seen in 13 cases (7.9%). With regard to tumor type, 4 of 111 HCC cases (3.5%), but 4 of 37 CC cases (10.5%), and even 5 of 16 CHCC cases (30%) were positive for this antitrypsin variant. In all but 1 of 13 cases of alpha-1-antitrypsin deficiency, the carcinoma developed in noncirrhotic liver tissue of elderly people (mean age, 62.9 years). In three patients, a heterozygous state of ATT (PiMZ) could be revealed using isoelectric focusing or direct genetic analysis. We conclude from our findings that CHCC and CC especially might be associated with PiZ alpha-1-antitrypsin deficiency. Primary liver carcinoma might develop even in a heterozygote state of PiZ alpha-1-antitrypsin deficiency without concurrent liver disease. Furthermore, liver cirrhosis is not a precondition for these tumors.

Liver disease associated with alpha1-antitrypsin deficiency

Alpha1-ATD is the most common metabolic liver disease in children for which liver transplantation is performed and, in adults, is associated with cirrhosis, hepatocellular carcinoma, and emphysema. It appears that only a proportion of patients with the deficiency develop clinical manifestations of this disease. Moreover, recent characterization of specific cellular and physiologic events have provided the basis for future potential therapeutic interventions.

Prognostic value of serum alpha-1-antitrypsin in hepatocellular carcinoma

To evaluate serum alpha-1-antitrypsin (A1AT) as a prognostic factor in hepatocellular carcinoma, we studied 75 consecutive patients (60 male, 15 female, mean age +/- SD 63.0 +/- 9.3 years) in whom hepatocellular carcinoma developed with pre-existing cirrhosis. Median survival time was 245 days (range 4-1568+). 30 patients had serum A1AT concentration of < or = 2.20 g/l (Group A) while 45 (Group B) had alpha-1-antitrypsin > 2.20 g/l. Median survival was 518 days in Group A and 81 days in Group B (Mantel-Cox 20.95, P < 0.0001; hazard ratio 0.26, 95% confidence limits 0.15-0.46). By stepwise survival analysis, alpha-1-antitrypsin together with bilirubin, tumour size and blood urea nitrogen were chosen among 17 variables as the only independent predictors of survival. We conclude that measurement of serum A1AT concentration might be useful as an inexpensive, widely available prognostic marker of hepatocellular carcinoma.

Prognosis and life expectancy on alpha-1-antitrypsin deficiency and chronic liver disease

BACKGROUND

Alpha-1-antitrypsin deficiency is a common autosomal recessive disorder associated with early development of emphysema, liver cirrhosis, and hepatocellular carcinoma. The aim of the present study was to define prognosis and life expectancy in patients with alpha 1-antitrypsin deficiency with and without chronic liver disease.

METHODS

After a follow-up of 15 years the estimated life table analysis of mortality of 160 patients with alpha 1-antitrypsin deficiency was retrospectively calculated. The survival time was estimated using the Kaplan-Meier survival curves and was compared with the life expectancy of the age- and sex-matched population of west Austria.

RESULTS

Fifty-four patients with alpha 1-antitrypsin patients had evidence of chronic liver disease; of these, 78% showed positive viral markers. Of the 106 patients with alpha 1-antitrypsin deficiency without chronic liver disease none had evidence of additional viral infection. Life expectancy in patients with alpha-1 antitrypsin deficiency and chronic liver disease was significantly lower than in patients with alpha 1-antitrypsin deficiency without chronic liver disease (p = 0.001). No difference in life expectancy in alpha 1-antitrypsin deficiency without chronic liver disease was found in comparison with that of the normal population.

CONCLUSIONS

We suggest that in alpha 1-antitrypsin deficiency-associated chronic liver disease it is the high coinfection rather than the inborn error of metabolism itself that is responsible for a deterioration of life expectancy or for the poor prognosis of the disease.

Prognosis and life expectancy in chronic liver disease

The aim of the present was to define prognosis and life expectancy in patients with chronic liver disease of different etiologies and to relate them to an age- and sex-matched normal population. After a follow-up of 15 years, life expectancy of 620 patients with chronic liver disease was retrospectively calculated and compared with an age- and sex-matched normal population. Among patients with cirrhosis, prognosis was dependent upon Child classification (P = 0.001). Patients with alcoholic cirrhosis and fatty liver disease were younger (P = 0.01) and had a lower life expectancy than patients with other causes of chronic liver disease (P = 0.004). Patients with hepatitis B and hepatitis C cirrhosis showed a comparable prognosis and a significantly lower life expectancy than the age- and sex-matched population. Cryptogenic and autoimmune liver diseases showed a comparable life expectancy but a significantly shorter life expectancy than the normal population. In patients with alpha 1-antitrypsin deficiency-associated cirrhosis, a high viral coinfection rate was found (P = 0.01). For patients with noncirrhotic hemochromatosis, prognosis was poorer than that for the age- and sex-matched population. In patients with asymptomatic primary biliary cirrhosis, chronic persistent hepatitis B, and alpha 1-antitrypsin deficiency without cirrhosis, life expectancy was equal to that of the normal population. Prognosis and life expectancy in chronic liver disease depend on stage, cause, and symptoms of chronic liver disease; age; and possibilities of treatment. In patients with hereditary liver disease, additional viral infection of alcohol abuse lead to a significant deterioration of life expectancy. Patients with alcoholic chronic liver disease have the poorest prognosis.