The Severity of Liver Fibrosis Influences the Prognostic Value of Inflammation-Based Scores in Hepatitis B-Associated Hepatocellular Carcinoma

BACKGROUND

This study was designed to evaluate the prognostic value of three systemic inflammation markers, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and prognostic nutritional index (PNI), for hepatocellular carcinoma (HCC) associated with hepatitis B (HBV).

METHODS

This analysis included 234 HBV-HCC patients who underwent primary surgical resection at the Mount Sinai Medical Center between 1988 and 2013. Serum albumin and circulating neutrophil, lymphocyte, and platelet counts immediately before surgery were obtained to calculate NLR, PLR, and PNI.

RESULTS

Patients with larger tumor size (>3 cm) had higher NLR, higher PLR, and lower PNI. Stratified analysis showed that the impact of three markers on outcome depends on the severity of liver fibrosis. High NLR, high PLR, or low PNI was associated with poor outcome only in patients without end-stage fibrosis (Ishak stage 0-5) and not in those with cirrhosis (Ishak stage 6). Multivariate analysis in Ishak stage 0-5 patients showed that only high NLR was associated with poor outcome independent of tumor size. Of the three markers, only NLR correlated with PD-L1 expression in center of tumor, but not in nonneoplastic liver.

CONCLUSIONS

The prognostic value of these three markers following surgery was only significant for HBV-HCC patients without end-stage fibrosis, and among the three markers, only NLR remained a significant prognostic indicator independent of tumor size. The correlation of NLR with intratumoral PD-L1 expression raises a hypothesis for shared pathways leading to PD-L1-mediated local tolerance within tumor and systemic inflammatory responses represented by elevated NLR in HBV-HCC.

Inhibition of the CXCL12/CXCR4 chemokine axis with AMD3100, a CXCR4 small molecule inhibitor, worsens murine hepatic injury

AIM

Activation of hepatic stellate cells and development of chronic inflammation are two key features in the progression of hepatic fibrosis. We have shown that in vitro activated stellate cells increase their expression of CXCL12 as well as the receptor CXCR4 and that receptor engagement promotes a profibrogenic phenotype. Furthermore, injury promotes increased hepatic expression of CXCL12 and a massive infiltration of CXCR4-expressing leukocytes, granulocytes and myeloid cells. The primary site of inflammatory cell accumulation is around the CXCL12-rich portal tracts and within fibrotic septae, indicating a role for CXCR4 during injury. In order to characterize the relevance of the CXCR4/CXCL12 chemokine axis during hepatic injury we inhibited the axis using AMD3100, a CXCR4 small molecule inhibitor, in models of chronic and acute liver injury.

METHODS

Mice were subjected to acute and chronic CCl4 liver injury with and without AMD3100 administration. The degree of liver injury, fibrosis and the composition of the intrahepatic inflammatory response were characterized.

RESULTS

Treatment of mice with AMD3100 in the chronic CCl4 model of liver injury led to an increase in hepatic inflammation and fibrosis with a specific increase in intrahepatic neutrophils. Furthermore, in an acute model of CCl4 -induced liver injury, AMD3100 led to an increase in the number of intrahepatic neutrophils and a trend towards worse necrosis.

CONCLUSION

Together, this data suggests that inhibition of the CXCR4/CXCL12 chemokine axis is injurious through modulation of the hepatic inflammatory response and that this axis may serve a protective role in liver injury.

β-PDGF receptor expressed by hepatic stellate cells regulates fibrosis in murine liver injury, but not carcinogenesis

BACKGROUND & AIMS

Rapid induction of β-PDGF receptor (β-PDGFR) is a core feature of hepatic stellate cell activation, but its cellular impact in vivo is not well characterized. We explored the contribution of β-PDGFR-mediated pathway activation to hepatic stellate cell responses in liver injury, fibrogenesis, and carcinogenesis in vivo using genetic models with divergent β-PDGFR activity, and assessed its prognostic implications in human cirrhosis.

METHODS

The impact of either loss or constitutive activation of β-PDGFR in stellate cells on fibrosis was assessed following carbon tetrachloride (CCl4) or bile duct ligation. Hepatocarcinogenesis in fibrotic liver was tracked after a single dose of diethylnitrosamine (DEN) followed by repeated injections of CCl4. Genome-wide expression profiling was performed from isolated stellate cells that expressed or lacked β-PDGFR to determine deregulated pathways and evaluate their association with prognostic gene signatures in human cirrhosis.

RESULTS

Depletion of β-PDGFR in hepatic stellate cells decreased injury and fibrosis in vivo, while its auto-activation accelerated fibrosis. However, there was no difference in development of DEN-induced pre-neoplastic foci. Genomic profiling revealed ERK, AKT, and NF-κB pathways and a subset of a previously identified 186-gene prognostic signature in hepatitis C virus (HCV)-related cirrhosis as downstream of β-PDGFR in stellate cells. In the human cohort, the β-PDGFR signature was not associated with HCC development, but was significantly associated with a poorer outcome in HCV cirrhosis.

CONCLUSIONS

β-PDGFR is a key mediator of hepatic injury and fibrogenesis in vivo and contributes to the poor prognosis of human cirrhosis, but not by increasing HCC development.

Liver Transplantation for Acute Intermittent Porphyria: Biochemical and Pathologic Studies of the Explanted Liver

Acute intermittent porphyria (AIP) is an autosomal-dominant hepatic disorder caused by the half-normal activity of hydroxymethylbilane (HMB) synthase. Symptomatic individuals experience life-threatening acute neurovisceral attacks that are precipitated by factors that induce the hepatic expression of 5-aminolevulinic acid synthase 1 (ALAS1), resulting in the marked accumulation of the putative neurotoxic porphyrin precursors 5-aminolevulinic acid (ALA) and porphobilinogen (PBG). Here, we provide the first detailed description of the biochemical and pathologic alterations in the explanted liver of an AIP patient who underwent orthotopic liver transplantation (OLT) due to untreatable and debilitating chronic attacks. After OLT, the recipient's plasma and urinary ALA and PBG rapidly normalized, and her attacks immediately stopped. In the explanted liver, (a) ALAS1 mRNA and activity were elevated approximately ~3- and 5-fold, and ALA and PBG concentrations were increased ~3- and 1,760-fold, respectively; (b) uroporphyrin III concentration was elevated; (c) microsomal heme content was sufficient, and representative cytochrome P450 activities were essentially normal; (d) HMB synthase activity was approximately half-normal (~42%); (e) iron concentration was slightly elevated; and (f) heme oxygenase I mRNA was increased approximately three-fold. Notable pathologic findings included nodular regenerative hyperplasia, previously not reported in AIP livers, and minimal iron deposition, despite the large number of hemin infusions received before OLT. These findings suggest that the neurovisceral symptoms of AIP are not associated with generalized hepatic heme deficiency and support the neurotoxicity of ALA and/or PBG. Additionally, they indicate that substrate inhibition of hepatic HMB synthase activity by PBG is not a pathogenic mechanism in acute attacks.

Utility of the low-accelerating-dose regimen in 182 liver recipients with recurrent hepatitis C virus

AIM

To describe our experience using a low-accelerating-dose regimen (LADR) with pegylated interferon alpha-2a and ribavirin in treatment of hepatitis C virus (HCV) recurrence.

METHODS

From 2003, a protocolized LADR strategy was employed to treat liver transplant (LT) recipients with recurrent HCV at our institution. Medical records of 182 adult patients with recurrent HCV treated with LADR between 1/2003 and 1/2011 were reviewed. Histopathology from all post-LT liver biopsies were reviewed in a blinded fashion. Paired recipient and donor IL28B status were assessed. A novel technique was employed to ascertain recipient and donor IL28B (rs12979860) Gt data using DNA extracted from archival FFPE tissue from explanted native livers and donor gallbladders respectively. The primary endpoint was SVR; secondary endpoints examined include (1) patient and graft survival; (2) effect of anti-viral therapy on liver histology (fibrosis and inflammation); (3) incidence of on-treatment development of ACR, CDR, or PCH; (4) association of recipient and donor IL28B genotype with SVR; and (5) incidence of anti-viral therapy-associated adverse events (anemia, leukopenia, thrombocytopenia, depression) and hepatic decompensation.

RESULTS

The overall SVR rate was 38% (29% Gt1, 67% Gt2, 86% Gt3 and 58% Gt4). HCV Gt (P < 0.0001), donor age (P = 0.003), cytomegalovirus mismatch (P = 0.001), baseline serum bilirubin (P = 0.002), and baseline viral load (P = 0.04) were independent predictors for SVR. SVR rates were significantly higher in the recipient-CC/donor-non CC pairs (P = 0.007). Neither baseline fibrosis nor change in fibrosis stage after anti-viral therapy were associated with SVR. Fibrosis progressed in 72% of patients despite SVR. Median graft survival was 91 mo. Five-year patient survival was superior in patients who achieved SVR (97% vs 82%, P = 0.001). Pre-treatment ALP ≥ 150 U/L (P = 0.01), total bilirubin ≥ 1.5 mg/dL (P = 0.001) and creatinine ≥ 2 mg/dL (P = 0.001) were independently associated with patient survival. Only 13% of patients achieving SVR died during the follow-up period. Treatment discontinuation and treatment-related mortality occurred in 35% and 2.2% of patients, respectively. EPO, G-CSF and blood transfusion were needed in 89%, 40% and 23% of patients, respectively. Overall hospitalization rate for treatment-related serious adverse events was 21%. Forty-six (25%) of the patients were deceased; among those who died, 25 (54%) were due to liver-related complications, and 4 deaths (9%) occurred while receiving therapy (2 patients experienced hepatic decompensation and 2 sepsis).

CONCLUSION

LADR strategy remains relevant in managing post-LT recurrent HCV where access to DAAs is limited. SVR is associated with improved survival, but fibrosis progression still occurs.

Primary sclerosing cholangitis: detailed histologic assessment and integration using bioinformatics highlights arterial fibrointimal hyperplasia as a novel feature

OBJECTIVES

Liver biopsy diagnosis of primary sclerosing cholangitis (PSC) is difficult. We performed a detailed histologic analysis of PSC cases using novel bioinformatics analysis to identify histologic features that may be useful in its diagnosis.

METHODS

PSC liver explants were examined and compared with primary biliary cirrhosis and hepatitis C explants to act as controls. Demographic, macroscopic, and histologic variables were analyzed using both conventional statistics and an integrative bioinformatics approach, significance analysis of microarrays (SAM), and hierarchical clustering analysis (HCA).

RESULTS

The PSC group was younger and had distinctive PSC features, including bile duct scars, onion-skin fibrosis, and arterial fibrointimal hyperplasia. SAM allowed the integration of variables by comparing PSC and control groups, whereas HCA was able to correctly categorize each group.

CONCLUSIONS

This study demonstrates characteristic PSC histology as well as arterial hyperplasia to be distinctive features that may aid in PSC diagnosis and be confirmed by bioinformatics.

Assessing prognostic significance of preoperative alpha-fetoprotein in hepatitis B-associated hepatocellular carcinoma: normal is not the new normal

BACKGROUND

Hepatitis B (HBV)-associated hepatocellular carcinoma (HCC) is often associated with alpha-fetoprotein (AFP) production. Although serum AFP has been demonstrated to be a prognostic factor for patient survival, optimal cutoff levels remain unclear.

METHODS

Patients with HBV-associated HCC treated by primary liver resection were prospectively followed at a single institution between 1995 and 2008. AFP level was categorized into quintiles for Kaplan–Meier analysis and multivariable Cox proportional hazards regression models.

RESULTS

Best 5-year survival after surgery was observed for patients with AFP in the first quintile (1.4-4.1 ng/mL), with progressively worse outcomes for patients in each increasing quintile. AFP was associated with overall survival (HR = 1.61; 95 % CI 1.30-1.98), disease-free survival (HR = 1.26; 95 % CI 1.10-1.44), and 2-year recurrence (HR = 1.30; 95 % CI 1.07-1.57) in multivariate analysis. Noncirrhotic patients (Ishak 1-5) with AFP in quintile 1 had 94 % 5-year survival, compared with 0 % survival for patients with AFP in quintile 5 (2,332.7-327,560.0 ng/mL) and Ishak stage 6 cirrhosis.

CONCLUSIONS

Preoperative serum AFP is an independent predictor of prognosis among HBV-HCC patients following surgical resection. Categorizing AFP into quintiles creates the opportunity to observe differences in outcomes even at low serum levels within the normal range. Additionally, combining AFP quintiles and fibrosis staging provides a predictive model of prognosis for HCC. Thus, even small differences in AFP within the normal range may impact prognosis and disease progression for HBV-HCC.

Lamivudine resistance leading to de novo hepatitis B infection in recipients of hepatitis B core antibody positive liver allografts

Most studies have shown that lamivudine (LAM) prophylaxis is sufficient to prevent hepatitis B virus (HBV) transmission in recipients of hepatitis B core antibody positive (HBcAb(+) ) allografts. However, de novo hepatitis B (DNHB) is known to occur in this patient population. Herein, we report a case series of four liver transplant recipients who developed DNHB after receiving HBcAb(+) allografts due to acquisition of LAM resistance mutations, suggesting that LAM prophylaxis may be suboptimal. A retrospective chart review was performed of all adult liver transplants performed at Mount Sinai from 2001 to 2010. A total of 79 patients received HBcAb(+) allografts for non-hepatitis B-related liver disease. Of these 79 recipients, four patients developed DNHB and were found to have documented LAM resistance. With the increasing use of HBcAb(+) donor livers, we suspect that there will also be a growing number of cases of DNHB due to acquisition of LAM resistance. We suggest that other agents, such as entecavir or tenofovir, be considered for use as prophylaxis in this patient population to decrease this risk.

Update on the new classification of hepatic adenomas: clinical, molecular, and pathologic characteristics

CONTEXT

Hepatic adenoma is an uncommon, benign, hepatic neoplasm that typically occurs in women of child-bearing age, often with a history of long-term use of oral contraceptive drugs. This is usually detected as an incidental mass lesion in a noncirrhotic liver during imaging studies. Pathologic evaluation by needle core biopsy remains the gold standard for diagnosis. Molecular studies have revealed that hepatic adenomas involve unique molecular pathways that are distinct from hepatocellular carcinoma. Based on these studies, a French collaborative group has recently proposed a molecular-pathologic classification for hepatic adenomas. In addition, advances in molecular studies have led to reclassification of the "telangiectatic variant of focal nodular hyperplasia" as "hepatic adenoma, inflammatory subtype."

OBJECTIVE

To review the proposed, new classification of hepatic adenoma and the changes in diagnostic workup in light of the above-mentioned developments.

DATA SOURCES

Review of published literature and illustrations from clinical case material.

CONCLUSIONS

Definitive diagnosis of liver mass lesion on needle core biopsies has a decisive role in clinical management. With the advent of the new classification of hepatic adenomas and its prognostic implications, it is vital for pathologists to be aware of the morphologic features seen in different subtypes and the available diagnostic tools, such as immunohistochemistry, to help identify the correct subtype.

NRBF2 regulates autophagy and prevents liver injury by modulating Atg14L-linked phosphatidylinositol-3 kinase III activity

The Beclin 1-Vps34 complex, the core component of the class III phosphatidylinositol-3 kinase (PI3K-III), binds Atg14L or UVRAG to control different steps of autophagy. However, the mechanism underlying the control of PI3K-III activity remains elusive. Here we report the identification of NRBF2 as a component in the specific PI3K-III complex and a modulator of PI3K-III activity. Through its MIT domain, NRBF2 binds Atg14L directly and enhances Atg14L-linked Vps34 kinase activity and autophagy induction. NRBF2 deficient cells exhibit enhanced vulnerability to ER stress that is reversed by re-introducing exogenous NRBF2. NRBF2 deficient mice develop focal liver necrosis and ductular reaction, accompanied by impaired Atg14L-linked Vps34 activity and autophagy, though the mice show no increased mortality. Our data reveals a key role for NRBF2 in the assembly of the specific Atg14L-Beclin 1-Vps34-Vps15 complex for autophagy induction. Thus, NRBF2 modulates autophagy via regulation of PI3K-III and prevents ER stress-mediated cytotoxicity and liver injury.

UHRF1 overexpression drives DNA hypomethylation and hepatocellular carcinoma

Ubiquitin-like with PHD and RING finger domains 1 (UHRF1) is an essential regulator of DNA methylation that is highly expressed in many cancers. Here, we use transgenic zebrafish, cultured cells, and human tumors to demonstrate that UHRF1 is an oncogene. UHRF1 overexpression in zebrafish hepatocytes destabilizes and delocalizes Dnmt1 and causes DNA hypomethylation and Tp53-mediated senescence. Hepatocellular carcinoma (HCC) emerges when senescence is bypassed. tp53 mutation both alleviates senescence and accelerates tumor onset. Human HCCs recapitulate this paradigm, as UHRF1 overexpression defines a subclass of aggressive HCCs characterized by genomic instability, TP53 mutation, and abrogation of the TP53-mediated senescence program. We propose that UHRF1 overexpression is a mechanism underlying DNA hypomethylation in cancer cells and that senescence is a primary means of restricting tumorigenesis due to epigenetic disruption.

DCE-MRI of the liver: effect of linear and nonlinear conversions on hepatic perfusion quantification and reproducibility

PURPOSE

To evaluate the effect of different methods to convert magnetic resonance (MR) signal intensity (SI) to gadolinium concentration ([Gd]) on estimation and reproducibility of model-free and modeled hepatic perfusion parameters measured with dynamic contrast-enhanced (DCE)-MRI.

MATERIALS AND METHODS

In this Institutional Review Board (IRB)-approved prospective study, 23 DCE-MRI examinations of the liver were performed on 17 patients. SI was converted to [Gd] using linearity vs. nonlinearity assumptions (using spoiled gradient recalled echo [SPGR] signal equations). The [Gd] vs. time curves were analyzed using model-free parameters and a dual-input single compartment model. Perfusion parameters obtained with the two conversion methods were compared using paired Wilcoxon test. Test-retest and interobserver reproducibility of perfusion parameters were assessed in six patients.

RESULTS

There were significant differences between the two conversion methods for the following parameters: AUC60 (area under the curve at 60 s, P < 0.001), peak gadolinium concentration (Cpeak, P < 0.001), upslope (P < 0.001), Fp (portal flow, P = 0.04), total hepatic flow (Ft, P = 0.007), and MTT (mean transit time, P < 0.001). Our preliminary results showed acceptable to good reproducibility for all model-free parameters for both methods (mean coefficient of variation [CV] range, 11.87-23.7%), except for upslope (CV = 37%). Among modeled parameters, DV (distribution volume) had CV <22% with both methods, PV and MTT showed CV <21% and <29% using SPGR equations, respectively. Other modeled parameters had CV >30% with both methods.

CONCLUSION

Linearity assumption is acceptable for quantification of model-free hepatic perfusion parameters while the use of SPGR equations and T1 mapping may be recommended for the quantification of modeled hepatic perfusion parameters.

Obliterative portal venopathy: a clinical and histopathological review

Non-cirrhotic portal hypertension (NCPH) is characterized by the elevation of the portal pressure in the absence of cirrhosis. Obliterative portal venopathy (OPV) as a cause of NCPH is being increasingly diagnosed, especially after recent reports of its occurrence in patients with HIV using didanosine. Patients usually present with episodes of variceal hemorrhage and other features of portal hypertension including jaundice, ascites, encephalopathy and hepatopulmonary syndrome. Hepatic synthetic function is typically well preserved and the laboratory evaluation in OPV patients typically reveals only mild nonspecific hematological abnormalities chiefly related to hypersplenism. Its diagnosis remains a challenge and patients are often mistakenly diagnosed as having cirrhosis. Despite the increasing recognition of OPV, its etiology and pathogenesis are still unclear. A number of etiologies have been proposed including genetic predisposition, recurrent bacterial infections, HIV infection and highly active antiretroviral therapy, an altered immune response, hypercoagulability, and exposure to chemicals and certain medications. Histopathological evaluation remains critical in excluding cirrhosis and other causes of portal hypertension, and is the only way of definitively establishing the diagnosis of OPV. Clinicians should have a high index of suspicion for OPV in patients who present with variceal bleeding and splenomegaly and who do not have other features of cirrhosis. The purpose of this review is to summarize the known etiologies for OPV and its associated clinical aspects and correlations, and to also provide ample histophotomicrographs of OPV to aid in the diagnosis. It will also help raise awareness of this entity amongst pathologists and clinicians alike.

Impact of liver fibrosis on prognosis following liver resection for hepatitis B-associated hepatocellular carcinoma

BACKGROUND

This study aims to evaluate the impact of liver fibrosis severity on prognosis following liver resection among HBV-HCC patients.

METHODS

Data were extracted from a prospective database of 189 HBV-HCC patients treated at Mount Sinai between 1995 and 2008. Fibrosis staging of each surgical resection specimen using the modified Ishak method was performed by a single liver pathologist.

RESULTS

A wide range of Ishak fibrosis stage was observed among this patient population, with 29% having established cirrhosis (Ishak stage 6). Ishak stage 6 was independently associated with poor overall and recurrence-free survival. In patients with Ishak stage 1-5, Ishak stage did not affect survival; rather, tumour size was associated with poor overall survival, and tumour size, histologic activity index and serum AFP>20 ng ml(-1) were associated with poor recurrence-free survival. In patients with Ishak stage 6, poorly differentiated histology and tumour size were associated with poor overall survival, and tumour size was associated with poor recurrence-free survival.

CONCLUSION

HBV-HCC develops with varying degrees of underlying liver fibrosis; however, progressive liver fibrosis does not affect the outcomes following resection until cirrhosis is reached. Established cirrhosis, as defined histologically by Ishak stage 6, is an independent predictor of poor overall and recurrence-free survival among these patients.

Medullary thymic epithelial cell depletion leads to autoimmune hepatitis

TRAF6, an E3 ubiquitin protein ligase, plays a critical role in T cell tolerance by regulating medullary thymic epithelial cell (mTEC) development. mTECs regulate T cell tolerance by ectopically expressing self-antigens and eliminating autoreactive T cells in the thymus. Here we show that mice with mTEC depletion due to conditional deletion of Traf6 expression in murine thymic epithelial cells (Traf6ΔTEC mice) showed a surprisingly narrow spectrum of autoimmunity affecting the liver. The liver inflammation in Traf6ΔTEC mice exhibited all the histological and immunological characteristics of human autoimmune hepatitis (AIH). The role of T cells in AIH establishment was supported by intrahepatic T cell population changes and AIH development after transfer of liver T cells into immunodeficient mice. Despite a 50% reduction in natural Treg thymic output, peripheral tolerance in Traf6ΔTEC mice was normal, whereas compensatory T regulatory mechanisms were evident in the liver of these animals. These data indicate that mTECs exert a cell-autonomous role in central T cell tolerance and organ-specific autoimmunity, but play a redundant role in peripheral tolerance. These findings also demonstrate that Traf6ΔTEC mice are a relevant model with which to study the pathophysiology of AIH, as well as autoantigen-specific T cell responses and regulatory mechanisms underlying this disease.

Post-transcriptional activation of PPAR alpha by KLF6 in hepatic steatosis

BACKGROUND & AIMS

Dysregulated glucose homeostasis and lipid accumulation characterize non-alcoholic fatty liver disease (NAFLD), but underlying mechanisms are obscure. We report here that Krüppel-like factor 6 (KLF6), a ubiquitous transcription factor that promotes adipocyte differentiation, also provokes the metabolic abnormalities of NAFLD by post-transcriptionally activating PPARα-signaling.

METHODS

Mice with either hepatocyte-specific depletion of KLF6 ('ΔHepKlf6') or global KLF6 heterozygosity (Klf6+/-) were fed a high fat diet (HFD) or chow for 8 or 16 weeks. Glucose and insulin tolerance tests were performed to assess insulin sensitivity. Overexpression and knockdown of KLF6 in cultured cells enabled the elucidation of underlying mechanisms. In liver samples from a cohort of 28 NAFLD patients, the expression of KLF6-related target genes was quantified.

RESULTS

Mice with global- or hepatocyte-depletion of KLF6 have reduced body fat content and improved glucose and insulin tolerance, and are protected from HFD-induced steatosis. In hepatocytes, KLF6 deficiency reduces PPARα-regulated genes (Trb3, Pepck) with diminished PPARα protein but no change in Pparα mRNA, which is explained by the discovery that KLF6 represses miRNA 10b, which leads to induction of PPARα. In NAFLD patients with advanced disease and inflammation, the expression of miRNA 10b is significantly downregulated, while PEPCK mRNA is upregulated; KLF6 mRNA expression also correlates with TRB3 as well as PEPCK gene expression.

CONCLUSIONS

KLF6 increases PPARα activity, whereas KLF6 loss leads to PPARα repression and attenuation of lipid and glucose abnormalities associated with a high fat diet. The findings establish KLF6 as a novel regulator of hepatic glucose and lipid metabolism in fatty liver.

Increased thickness of abdominal subcutaneous adipose tissue occurs more frequently in steatohepatitis than in simple steatosis

CONTEXT

The incidence of obesity is increasing and contributes to the rising incidence of fatty liver. Body mass index (BMI) is used to assess the degree of obesity but does not take into account the pattern of body fat distribution.

OBJECTIVES

To confirm the increasing incidence of fatty liver in an autopsy study. We hypothesized that a standardized measurement of abdominal subcutaneous adipose tissue (ASAT) might be a good noninvasive method for differentiating steatohepatitis from steatosis.

DESIGN

Consecutive complete adult postmortem cases were studied and liver sections were assessed with a steatohepatitis scoring system. Spleen weight, ASAT, and clinical information were obtained. Spleen histology was assessed in a subset of patients having splenomegaly in the absence of cirrhosis.

RESULTS

Patients with human immunodeficiency virus, hepatitis C virus, and appreciable alcohol use were excluded. Of 306 cases, the frequency of fatty liver was 51.6% with 33.3% having simple steatosis and 18.3%, having steatohepatitis. Mean ASAT was 3.7 cm in the steatohepatitis group versus 2.6 cm in the steatosis group (P < .001); this difference was greater in patients with a BMI less than 25 kg/m(2) (P = .05). Fibrocongestive splenomegaly was noted in 9 of 38 patients with nonalcoholic steatohepatitis (24%) in the absence of cirrhosis.

CONCLUSIONS

In this series of autopsy cases, a dramatic increase in the prevalence of fatty liver disease is demonstrated. Thicker ASAT is associated more with steatohepatitis than with simple steatosis, especially in patients with BMI below 25 kg/m(2). Fibrocongestive splenomegaly may occur in the absence of cirrhosis in the presence of steatohepatitis.

Rapid regression of atherosclerosis with MTP inhibitor treatment

OBJECTIVE

Regression of atherosclerosis is a vital treatment goal of atherosclerotic vascular disease. Inhibitors of the microsomal triglyceride transfer protein (MTP) have been shown to reduce apolipoprotein B (apoB)-containing lipoproteins in animals and humans effectively. Therefore, the major aim of our study is to evaluate the effect of MTP inhibition on atherosclerotic plaque regression.

METHODS

LDL-receptor-deficient (LDLr(-/-)) mice were fed a Western diet for 16 weeks and then harvested for baseline (n = 8), switched to chow diet (n = 8) or chow diet containing MTP inhibitor (BMS 212122; n = 8) for 2 weeks before harvesting.

RESULTS

Treatment with MTP inhibitor led to rapid reduction in plasma lipid levels, which were accompanied by a significant decrease in lipid content and monocyte-derived (CD68+) cells in atherosclerotic plaques compared to baseline and chow diet control groups. MTP inhibitor-treated mice had increased collagen content, a marker associated with increased stability in human plaques. Furthermore, plaques of these mice showed a significant decrease in tissue factor and pro-inflammatory M1 macrophage marker monocyte chemoattractant protein-1 (MCP-I) and an increase in anti-inflammatory M2 macrophage markers arginase-I and mannose receptor 1 compared to mice in the baseline group.

CONCLUSION

Reversal of hyperlipidemia in atherosclerotic mice by inhibition of MTP leads to rapid and beneficial changes in the composition and inflammatory state of the plaque.

Rapid progression to decompensated cirrhosis, liver transplant, and death in HIV-infected men after primary hepatitis C virus infection

BACKGROUND

We and others have shown that primary hepatitis C (HCV) infection in men infected with human immunodeficiency virus (HIV) causes early-onset liver fibrosis; however, little is known about the long-term natural history of the liver disease in these HIV-infected men.

METHODS

We followed a cohort of HIV-infected men with primary HCV infection in New York City.

RESULTS

Four men who were not cured after their primary HCV infection developed decompensated cirrhosis within 17 months to 6 years after primary HCV infection. Three died within 8 years of primary HCV infection, and 1 survived after liver transplant done 2 years after primary HCV infection. Three of the 4 men had AIDS at the time of primary HCV infection, and the most rapid progression occurred in the 2 men with the lowest CD4 counts at the time of HCV infection. Liver histopathology was most consistent with HCV-induced damage even though some had exposures to other potential hepatotoxins.

CONCLUSIONS

Primary HCV infection resulted in decompensated cirrhosis and death within 2-8 years in 4 HIV-infected men. The rapid onset of fibrosis due to primary HCV infection in HIV-infected men cannot therefore be considered benign. The rate of continued progression to liver failure may be proportional to the degree of underlying immunocompromise caused by HIV infection. More research is needed to better define the mechanisms behind accelerated liver damage.

Diffusion-weighted imaging of the liver with multiple b values: effect of diffusion gradient polarity and breathing acquisition on image quality and intravoxel incoherent motion parameters--a pilot study

PURPOSE

To optimize intravoxel incoherent motion (IVIM) diffusion-weighted (DW) imaging by estimating the effects of diffusion gradient polarity and breathing acquisition scheme on image quality, signal-to-noise ratio (SNR), IVIM parameters, and parameter reproducibility, as well as to investigate the potential of IVIM in the detection of hepatic fibrosis.

MATERIALS AND METHODS

In this institutional review board-approved prospective study, 20 subjects (seven healthy volunteers, 13 patients with hepatitis C virus infection; 14 men, six women; mean age, 46 years) underwent IVIM DW imaging with four sequences: (a) respiratory-triggered (RT) bipolar (BP) sequence, (b) RT monopolar (MP) sequence, (c) free-breathing (FB) BP sequence, and (d) FB MP sequence. Image quality scores were assessed for all sequences. A biexponential analysis with the Bayesian method yielded true diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (PF) in liver parenchyma. Mixed-model analysis of variance was used to compare image quality, SNR, IVIM parameters, and interexamination variability between the four sequences, as well as the ability to differentiate areas of liver fibrosis from normal liver tissue.

RESULTS

Image quality with RT sequences was superior to that with FB acquisitions (P = .02) and was not affected by gradient polarity. SNR did not vary significantly between sequences. IVIM parameter reproducibility was moderate to excellent for PF and D, while it was less reproducible for D*. PF and D were both significantly lower in patients with hepatitis C virus than in healthy volunteers with the RT BP sequence (PF = 13.5% ± 5.3 [standard deviation] vs 9.2% ± 2.5, P = .038; D = [1.16 ± 0.07] × 10(-3) mm(2)/sec vs [1.03 ± 0.1] × 10(-3) mm(2)/sec, P = .006).

CONCLUSION

The RT BP DW imaging sequence had the best results in terms of image quality, reproducibility, and ability to discriminate between healthy and fibrotic liver with biexponential fitting.

Quantitative analysis of intrahepatic hepatitis B (HBV) DNA and cccDNA and their impact on survival posthepatectomy in HBV-associated hepatocellular carcinoma (HCC) patients

e14583

Background: Little is known about the prognostic significance of total intrahepatic HBV DNA (ihHBV DNA) and cccDNA, a stable episome that accumulates in the nuclei and serves as the template for viral replication. This study aims to quantitate ihHBV DNA and cccDNA in the non-neoplastic liver and to assess their impact on prognosis in HBV-HCC patients. Methods: 111 patients, many on HBV antivirals, who underwent liver resection for HBV-HCC from 1991 to 2008 were assessed by real time PCR for ihHBV DNA, cccDNA, and albumin. Liver fibrosis and necroinflammation was assessed using the modified Ishak method. Independent variables associated with survival were analyzed using multivariate Cox regression model, with a median follow up for survivors of 52 months. Results: Serum HBV DNA was detectable in only 42% of patients, but 106 patients (95%) had detectable ihHBV DNA (median: 0.018copy/hepatocyte); and 89 patients (80%) had detectable cccDNA (0.00058 copy/hepatocyte). Median cccDNA/ihHBV DNA ratio was 0.019. ihHBV DNA correlated with histologic activity index (p = 0.04) and serum ALT (p = 0.004). Patients in the lowest quartile of cccDNA/ihHBV DNA ratio (<0.0032) trended towards poor overall 5-year survival by univariate analysis (p = 0.09), with higher mortality at 2 years (89% vs. 45%, p = 0.03). In multivariate analysis, AFP > 20, Ishak fibrosis stage 6 (established cirrhosis), cccDNA/ihHBV DNA < 0.0032, and large tumor diameter were independently associated with poor overall survival (Table). Conclusions: ihHBV DNA levels were associated with severity of liver necroinflammation and injury. ihHBV DNA and cccDNA levels were not associated with survival; rather, low proportion of total HBV DNA in the form of cccDNA was independently associated with poor overall survival. Thus, viral behavior at the time of liver resection influences clinical outcome for HBV-HCC patients. [Table: see text]