Metabolic syndrome and hepatocellular carcinoma: two growing epidemics with a potential link

Influence of metabolic and other clinicopathologic factors on the prognosis of patients with hepatocellular carcinoma undergoing hepatic resection

Backgrounds/Aims

The prognosis of hepatic resection for hepatocellular carcinoma (HCC) in patients with cirrhosis is worse than in those without cirrhosis. In Korea, the hepatitis B virus prevalence rate is higher than in other countries. Therefore, we investigated patients' clinicopathologic and metabolic factors that affect the postoperative outcomes of hepatic resection for HCC in our hospital in Korea.

Methods

From August 2000 to December 2012, 171 HCC patients underwent hepatic resections at our institution. Two operative mortality cases and two short-term follow up cases were excluded. Data was collected from a retrospective chart review. There were 133 males (79.6%) and 34 females (20.3%), with a mean age of 58.2±10.2 years (range, 22-81 years), and the relationship between clinicopathologic and metabolic factors and the prognosis of patients with HCC undergoing hepatic resection were evaluated by univariate and multivariate analysis.

Results

Hypertension, major surgery, perioperative transfusion, resection with radiofrequency ablation (RFA) or cryoablation, and resection margin were risk factors for overall survival, and hypertension, albumin, resection with RFA or cryoablation, perioperative transfusion, and tumor size were risk factors for disease-free survival.

Conclusions

We found that hypertension, perioperative transfusion, and resection with RFA or cryoablation were risk factors for both disease-free and overall survival after hepatic resection in HCC patients. Further study is required to clarify the influence of metabolic and other clinicopathologic factors on the prognosis of HCC.

Liver resection for hepatocellular carcinoma in patients with metabolic syndrome: A multicenter matched analysis with HCV-related HCC

BACKGROUND & AIMS

The incidence of metabolic syndrome-related hepatocellular carcinoma (MS-HCC) is increasing worldwide. High resection risks are anticipated because of underlying steatohepatitis, but long-term results are unknown. To clarify the outcomes following liver resection in patients with MS-HCC and to compare the outcomes of MS-HCC to HCV-related HCC (HCV-HCC).

METHODS

All the consecutive patients undergoing liver resection for HCC in six high-volume HPB units between 2000 and 2012 were retrospectively considered. The patients with MS-HCC were identified and matched one-to-one with HCV-HCC patients without metabolic syndrome. Matching was based on age, cirrhosis, Child-Pugh class, portal hypertension, HCC number and diameter and liver resection extension.

RESULTS

Among 1563 patients undergoing liver resection for HCC in the study period, 96 (6.1%) had MS-HCC. They were matched with 96 HCV-HCC patients. All patients were Child-Pugh class A, 22.9% had cirrhosis. Forty-one patients per group (42.7%) required major hepatectomy. The MS-HCC group had a higher prevalence of steatohepatitis (25.0% vs. 9.4%, p=0.004). Operative mortality was 2.1% (1 MS-HCC, 3 HCV-HCC, p=0.621). Morbidity and liver failure rates were similar between the two groups. In the multivariate analysis, cirrhosis, major hepatectomy, and MELD >8, but not steatohepatitis, impacted severe morbidity and liver failure rates. The MS-HCC group had better 5-year overall survival (65.6% vs. 61.4%, p=0.031) and recurrence-free survival (37.0% vs. 27.5%, p=0.077). Independent negative prognostic factors were HCV-HCC, multiple HCC, microvascular invasion, and satellite nodules.

CONCLUSIONS

Liver resection is safe for MS-HCC, as for HCV-HCC. Cirrhosis, but not steatohepatitis, affects short-term outcomes. MS-HCC is associated with excellent long-term outcomes, better than HCV-HCC.

Multifaceted roles of HSF1 in cancer

Heat shock transcription factor 1 (HSF1) is the master regulator of the heat shock response. Accumulating evidence shows that HSF1 is overexpressed in a variety of human cancers, is associated with cancer aggressiveness, and could serve as an independent diagnostic or prognostic biomarker. In this review, we will provide an overview of the multifaceted roles of HSF1 in cancer, with a special focus on the four underlying molecular mechanisms involved. First, HSF1 regulates the expression of heat shock proteins (HSPs) including HSP90, HSP70, and HSP27. Second, HSF1 regulates cellular metabolism, including glycolysis and lipid metabolism. Third, HSF1 serves as a regulator of different signaling pathways, such as HuR-HIF-1, Slug, protein kinase C (PKC), nuclear factor-kappaB (NF-κB), PI3K-AKT-mTOR, and mitogen-activated protein kinase (MAPK) pathways. Finally, HSF1 regulates microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Overall, HSF1 plays many important roles in cancer via regulating cell proliferation, anti-apoptosis, epithelial-mesenchymal transition (EMT), migration, invasion, and metastasis and may be a potential therapeutic target for human cancers.

Nonalcoholic Fatty liver disease, diabetes, obesity, and hepatocellular carcinoma

Diabetes and obesity are associated with nonalcoholic fatty liver disease (NAFLD) and an increased incidence of hepatocellular carcinoma (HCC). NAFLD is the commonest cause of chronic liver disease. HCC can develop in NAFLD patients even without cirrhosis, suggesting an association between the metabolic process and HCC and raising a concern that many cancers could be missed given high NAFLD prevalence and screening limitations. The increasing prevalence of these conditions and lack of effective treatments necessitate a better understanding of their connection. This article defines the known interrelationships and common pathways between NAFLD, diabetes, obesity and HCC and possible chemoprevention strategies.

Potential epigenetic mechanism in non-alcoholic Fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is characterized by excessive fat accumulation in the liver. It ranges from simple steatosis to its more aggressive form, non-alcoholic steatohepatitis (NASH), which may develop into hepatic fibrosis, cirrhosis, or hepatocellular carcinoma (HCC) if it persists for a long time. However, the exact pathogenesis of NAFLD and the related metabolic disorders remain unclear. Epigenetic changes are stable alterations that take place at the transcriptional level without altering the underlying DNA sequence. DNA methylation, histone modifications and microRNA are among the most common forms of epigenetic modification. Epigenetic alterations are involved in the regulation of hepatic lipid metabolism, insulin resistance, mitochondrial damage, oxidative stress response, and the release of inflammatory cytokines, all of which have been implicated in the development and progression of NAFLD. This review summarizes the current advances in the potential epigenetic mechanism of NAFLD. Elucidation of epigenetic factors may facilitate the identification of early diagnositic biomarkers and development of therapeutic strategies for NAFLD.

Physical Activity is Related to Fatty Liver Marker in Obese Youth, Independently of Central Obesity or Cardiorespiratory Fitness

Nonalcoholic fatty liver disease (NAFLD) is one of the most frequent complications associated with excess adiposity and has been identified as the leading cause of liver disease in pediatric populations worldwide. Because cardiorespiratory fitness (CRF) is related to physical activity (PA) levels, and increased PA plays a protective role against NAFLD risk factors, the aim of this study was to analyze the association between PA and a fatty liver marker (alanine aminotransferase - ALT) in obese children and adolescents, independently of central adiposity or CRF. 131 obese children (83 girls, 7-15 year-olds) involved in a PA promotion program comprised the sample. Measurements included anthropometric and body composition evaluations (DEXA), biological measurements (venipuncture), CRF (progressive treadmill test), PA (accelerometry), and maturational stage (Tanner criteria). The associations between ALT with PA intensities, central obesity, and CRF were calculated by three different models of linear regression, adjusted for potential confounders. Level of significance was set at 95%.

RESULTS

ALT was negatively associated with MVPA (β = -0.305), and CRF (β = -0.426), and positively associated with central obesity (β=.468). After adjustment for central obesity the negative and statistically significant association between ALT with MVPA (β = -0.364) and CRF (β = -0.550) still persists while a positive and significantly correlation was shown between ALT and SB (β = 0.382). Additional adjustment for CRF (Model 3) showed significant associations for all the PA intensities analyzed including light activity. PA at different intensities is associated to a fatty liver marker in obese children and adolescents, independently of central adiposity or CRF. Key pointsIn a previous study our group observed that there might be a potential protective effect of cardiorespiratory fitness (CRF) against abnormal ALT values;Considering that CRF is related to physical activity (PA), and increased PA plays a protective role against fatty liver, we hypothesized that it might be an association between PA and fatty liver in obese youth, independently of central adiposity or CRF;No other study has investigated these associations in obese youth;Our findings stresses the fact that moderate-to-vigorous and light physical activities, as well as lower sedentary behavior, is associated with lower fatty liver marker, independent of the effect of potential mediators, such as central obesity or CRF.

Clinical significance of enteral nutrition therapy for elderly patients with nonalcoholic fatty liver disease associated with metabolic syndrome

AIM: To explore the clinical significance of enteral nutrition therapy for elderly patients with nonalcoholic fatty liver disease associated with metabolic syndrome.

METHODS: A total of 120 patients diagnosed with nonalcoholic fatty liver disease with metabolic syndrome between May 2009 and May 2014 were randomly divided into either an enteral nutrition group or a parenteral nutrition group, with 60 cases in each group. The demographic data, such as age, sex and severity of illness, had no statistical difference (P > 0.05).

RESULTS: The body mass index (BMI), fasting plasma glucose (FPG), glycosylated hemoglobin (HbAlc), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), total bilirubin (TBIL), direct bilirubin (DBIL), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly in the enteral nutrition group after treatment (P < 0.05), although the waist-to-hip ratio, triceps skin fold (TSF), cholesterol, and high-density lipoprotein cholesterol (HDL-C) showed no obvious difference (P > 0.05) between before and after the treatment. In the parenteral nutrition group, the BMI, FPG and HbAlc significantly increased after therapy (P > 0.05), while the 2-h postprandial blood glucose level (2-h FBG), TC, HDL-C, and LDL-C had no significant changes (P > 0.05).

CONCLUSION: Enteral nutrition is more effective than parenteral nutrition in protecting liver functions, lowering the BMI and regulating sugar and fat metabolism in elderly patients with nonalcoholic fatty liver disease associated with metabolic syndrome.

Lysophosphatidic acid receptor LPAR6 supports the tumorigenicity of hepatocellular carcinoma

The aberrant processes driving hepatocellular carcinoma (HCC) are not fully understood. Lysophosphatidic acid receptors (LPAR) are commonly overexpressed in HCC, but their contributions to malignant development are not well established. In this report, we show that aberrant expression of LPAR6 sustains tumorigenesis and growth of HCC. Overexpression of LPAR6 in HCC specimens associated with poor survival in a cohort of 128 patients with HCC. We took a genetic approach to elucidate how LPAR6 sustains the HCC tumorigenic process, including through an expression profiling analysis to identify genes under the control of LPAR6. RNAi-mediated attenuation of LPAR6 impaired HCC tumorigenicity in tumor xenograft assays. Expression profiling and mechanistic analyses identified Pim-3 as a pathophysiologically relevant LPAR6 target gene. In nonmalignant cells where LPAR6 overexpression was sufficient to drive malignant character, Pim-3 was upregulated at the level of transcription initiation through a STAT3-dependent mechanism. A further analysis of HCC clinical specimens validated the connection between overexpression of LPAR6 and Pim-3, high proliferation rates, and poorer survival outcomes. Together, our findings establish LPAR6 as an important theranostic target in HCC tumorigenesis.

New discriminant score to predict the fibrotic stage of non-alcoholic steatohepatitis in Japan

Background and aim

Currently, non-alcoholic steatohepatitis (NASH) can only be diagnosed histopathologically. Our objective was to establish a new scoring system for the fibrotic stage of NASH.

Methods

We enrolled 139 patients with histologically proven NASH and divided them into two groups to construct (n = 90) and validate (n = 49) a fibrotic score for NASH (FSN). We used 17 variables and their natural logarithmic transformations in the multivariate analysis. To assess the accuracy of the FSN in determining NASH advanced fibrosis (stages 3–4), we compared various fibrotic scores for NASH.

Results

In the construct group, multivariate regression analysis ultimately obtained the following function: z = 1.022 × ln (type IV collagen 7S) (ng/mL) − 0.00680 × (platelet count) (×10⁹/L) + 1.925 × ln (AST) (IU/L) − 1.239 × ln (ALT) (IU/L) + 0.249. Median values of the FSN for stages 1, 2, 3 and 4 were 1.87, 2.14, 3.26 and 3.89, respectively. The multiple regression coefficient and coefficient of determination were 0.70 and 0.46, respectively. In the validation group, the median value was 2.00, 2.83, 3.08 and 4.37 in each stage. With regard to the utility of the FSN for predicting advanced fibrosis of NASH (stage ≥3), the area under the receiver operating characteristic curves (AUROC), 0.909 (95 % CI 0.847–0.970, p < 0.001), was higher than that for the other fibrotic scores (APRI, NAFLD fibrosis score, FIB-4 index, BARD score, NIKEI) in the construct group.

Conclusions

This simple scoring system accurately predicts fibrotic stage and discriminates patients with advanced fibrosis of NASH.

A biphasic response pattern of lipid metabolomics in the stage progression of hepatitis B virus X tumorigenesis

Metabolic syndrome has closely linked to the development of human hepatocellular carcinoma (HCC). By using the hepatitis B virus (HBV) X (HBx) transgenic mouse model, we studied the dynamic evolution of serum and liver profiles of lipids and global cDNA expression at different stages of HBx tumorigenesis. We observed that the lipid (triglycerides, cholesterol, and fatty acids) profiles revealed a biphasic response pattern during the progression of HBx tumorigenesis: a small peak at early phase and a large peak or terminal switch at the tumor phase. By analyzing cDNA microarray data, the early peak correlated to the oxidative stress and pro-inflammatory response, which then resolved at the middle phase and were followed by the terminal metabolic switch in the tumor tissues. Five lipid metabolism-related genes, the arachidonate 5-lipoxygenase, lipoprotein lipase, fatty acid binding protein 4, 1-acylglycerol-3-phosphate O-acyltransferase 9, and apolipoprotein A-IV were identified to be significantly activated in HBx transgenic HCCs and further validated in human HBV-related HCCs. Inhibition of these lipid genes could reverse the effect of HBx on lipid biosynthesis and suppress HBx-induced cell proliferation in vitro. Our results support the concept that metabolic syndrome plays an important role in HBV tumorigenesis. The dysregulation of lipid metabolic genes may predict the disease progression to HCC in chronic hepatitis B patients.

Mitochondrial sirtuins: emerging roles in metabolic regulations, energy homeostasis and diseases

The energy production and metabolic homeostasis are well-orchestrated networks of carbohydrate, lipid and protein metabolism. These metabolic pathways are integrated by a key cytoplasmic organelle, the mitochondria, leading to production of many metabolic intermediates and harvest cellular energy in the form of ATP. Sirtuins are a highly conserved family of proteins that mediate cellular physiology and energy demands in response to metabolic inputs. Mitochondria inhabit three main types of sirtuins classified as Sirt3, Sirt4 and Sirt5. These sirtuins regulate mitochondrial metabolic functions mainly through controlling post-translational modifications of mitochondrial protein. However, the biological mechanism involved in controlling mitochondrial metabolic functions is not well understood at this stage. In this review the current knowledge on how mitochondrial sirtuins govern mitochondrial functions including energy production, metabolism, biogenesis and their involvement in different metabolic pathways are discussed. The identifications of potential pharmacological targets of sirtuins in the mitochondria and the bioactive compounds that target mitochondrial sirtuins will increase our understanding on regulation of mitochondrial metabolism in normal and disease state.

MDM2-p53 pathway in hepatocellular carcinoma

Abnormalities in the TP53 gene and overexpression of MDM2, a transcriptional target and negative regulator of p53, are commonly observed in cancers. The MDM2-p53 feedback loop plays an important role in tumor progression and thus, increased understanding of the pathway has the potential to improve clinical outcomes for cancer patients. Hepatocellular carcinoma (HCC) has emerged as one of the most commonly diagnosed forms of human cancer; yet, the current treatment for HCC is less effective than those used against other cancers. We review the current studies of the MDM2-p53 pathway in cancer with a focus on HCC and specifically discuss the impact of p53 mutations along with other alterations of the MDM2-p53 feedback loop in HCC. We also discuss the potential diagnostic and prognostic applications of p53 and MDM2 in malignant tumors as well as therapeutic avenues that are being developed to target the MDM2-p53 pathway.

The clinical significance of serum ferritin in pediatric non-alcoholic Fatty liver disease

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) in children has become an important public health issue because of its high prevalence and severity. Several noninvasive methods for estimating NAFLD are under investigation. We aimed to evaluate the usefulness of serum ferritin as a biomarker of severity of pediatric NAFLD patients.

METHODS

A total of 64 NAFLD patient were enrolled from Severance Children's Hospital from March 2010 to February 2013. Serum ferritin levels, liver related laboratory tests, liver magnetic resonance imaging (MRI) (2-dimensional [2D] proton density-fat fraction) and NAFLD severity markers were compared between obese group and overweight group. Correlation analyses were performed between serum ferritin and laboratory values including NAFLD severity markers.

RESULTS

In obese group, serum ferritin, alanine aminotransferase (ALT), total bilirubin, international normalized ratio (INR), MRI 2D proton density-fat fraction, aspartate aminotransferase (AST) to platelet ratio index (APRI) and fibrosis-4 (FIB-4) (an index score calculated from platelet count, ALT, AST and age) were significantly higher than those of overweight group. NAFLD severity markers, APRI and FIB-4, and liver specific important laboratory values, AST, ALT, INR, cholesterol, triglyceride and low density lipoprotein show significant correlation with serum ferritin in NAFLD patients.

CONCLUSION

Serum ferritin concentrations could be a candidate of useful severity marker in the pediatric NAFLD patients.

Impact of Hepatic Steatosis on Disease-Free Survival in Patients with Non-B Non-C Hepatocellular Carcinoma Undergoing Hepatic Resection

BACKGROUND

Although the prevalence of non-B non-C hepatocellular carcinoma (NBNC HCC) has increased, its clinicopathologic characteristics remain unclear.

METHODS

We retrospectively analyzed 518 HCC patients who underwent hepatic resection. Hepatitis B surface antigen- and hepatitis C antibody-negative patients were categorized into the NBNC HCC group (n = 145); others were categorized into the hepatitis B or C HCC (BC HCC) group (n = 373). We subdivided the etiologies of NBNC HCC according to alcohol intake and presence of steatosis.

RESULTS

NBNC HCC was associated with nonalcoholic fatty liver disease (NAFLD) (13.1 %), fatty liver disease with moderate alcohol intake (9.0 %), alcoholic liver disease (ALD) (29.7 %), cryptogenic disease (44.1 %), and other known etiologies (4.1 %). The prevalence of obesity, diabetes mellitus, and hypertension was higher and hepatic function was better in the NBNC HCC group, which had significantly larger tumors than the BC HCC group. The entire NBNC HCC group displayed similar overall and disease-free survival as the BC HCC group. Among the subdivisions, NAFLD-associated HCC patients had significantly better disease-free survival than ALD-associated HCC and BC HCC patients. Microvascular invasion (hazard ratio [HR] 2.30; 95 % confidence interval [CI] 1.33-3.96) and steatosis area <5 % of noncancerous region (HR 2.13; 95 % CI 1.21-3.93) were associated with disease-free survival in NBNC HCC patients.

CONCLUSIONS

The prognosis of NBNC HCC was similar to that of BC HCC. Among NBNC HCC patients, NAFLD-associated HCC patients had a relatively low recurrence risk. Absence of steatosis in hepatic parenchyma had a significant impact on disease-free survival in NBNC HCC patients.

Activation of ATP citrate lyase by mTOR signal induces disturbed lipid metabolism in hepatitis B virus pre-S2 mutant tumorigenesis

The development of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) has been found to be associated with disturbed lipid metabolism. To elucidate the role of lipid metabolism in HBV tumorigenesis, we investigated the dynamic pattern of lipid metabolism in HBV pre-S2 mutant-induced tumorigenesis. Lipid and gene expression profiles were analyzed in an in vitro culture system and in transgenic mouse livers harboring HBV pre-S2 mutant. The pre-S2 mutant transgenic livers showed a biphasic pattern of lipid accumulation, starting from mild fatty change in early (1 month) transgenic livers, which subsided and then, remarkably, increased in HCC tissues. This biphasic pattern was synchronized with ATP citrate lyase (ACLY) activation. Further analyses revealed that the pre-S2 mutant initiated an endoplasmic reticulum (ER) stress-dependent mammalian target of rapamycin (mTOR) signalling cascade. The pre-S2 mutant-induced mTOR signal activated the sterol regulatory element binding transcription factor 1 (SREBF1) to upregulate ACLY, which then activated the fatty acid desaturase 2 (FADS2), mediated through ACLY-dependent histone acetylation. Such an ER stress-dependent mTOR signal cascade also is important for the proliferation of hepatocytes in vitro and is further validated in HBV-related HCC tissues.

IMPORTANCE

Aberrations of lipid metabolism frequently occur in chronic HBV infection. Our results provide a potential mechanism of disturbed lipid metabolism in HBV pre-S2 mutant-induced tumorigenesis, which should be valuable for the design of HCC chemoprevention in high-risk HBV carriers.

Serum HBV surface antigen positivity is associated with low prevalence of metabolic syndrome in Korean adult men

Background

Metabolic syndrome has clinical implications for chronic liver disease, but the relationship between chronic hepatitis B and metabolic syndrome remains unclear. The aim of this study was to determine whether hepatitis B surface antigen (HBsAg) positivity is associated with metabolic syndrome.

Methods

Data were obtained from the Third Korean National Health and Nutrition Examination Survey (KNHANES). Participant sera were tested for HBsAg. Metabolic syndrome was defined according to the modified National Cholesterol Education Program Adult Treatment Panel III guidelines for Koreans.

Results

Of the 5108 participants, 209 (4.1%) tested positive for HBsAg, and 1364 (26.7%) were diagnosed with metabolic syndrome. The prevalence of metabolic syndrome was 23.4% in HBsAg-positive men, 31.5% in HBsAg-negative men, 18.6% in HBsAg-positive women, and 23.7% in HBsAg-negative women. After adjusting for multiple factors, male participants who tested positive for serum HBsAg had an odds ratio of 0.612 (95% confidence interval [CI] 0.375–0.998) for metabolic syndrome and an odds ratio of 0.631 (95% CI 0.404–0.986) for elevated triglycerides. Women who tested positive for serum HBsAg had an odds ratio of 0.343 (95% CI 0.170–0.693) for elevated triglycerides.

Conclusions

Positive results for serum HBsAg are inversely associated with metabolic syndrome in men and with elevated triglycerides in men and women. This suggests that elevated triglycerides may contribute to the inverse association between HBsAg and metabolic syndrome.

Serum adiponectin is associated with worsened overall survival in a prospective cohort of hepatocellular carcinoma patients

BACKGROUND

Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide. The rise in metabolic syndrome has contributed to this trend. Adipokines, such as adiponectin, are associated with prognosis in several cancers, but have not been well studied in HCC.

METHODS

We prospectively enrolled 140 patients with newly diagnosed or recurrent HCC with Child-Pugh (CP) class A or B cirrhosis. We examined associations between serum adipokines, clinicopathological features of HCC, and time to death. We also examined a subset of tumors with available pathology for tissue adiponectin receptor (AR) expression by immunohistochemistry.

RESULTS

The median age of subjects was 62 years; 79% were men, 59% had underlying hepatitis C, and 36% were diabetic. Adiponectin remained a significant predictor of time to death (hazard ratio 1.90; 95% confidence interval 1.05-3.45; p = 0.03) in a multivariable adjusted model that included age, alcohol history, CP class, stage, and serum α-fetoprotein level. Cytoplasmic AR expression (AR1 and AR2) in tumors trended higher in those with higher serum adiponectin levels and in those with diabetes mellitus, but the association was not statistically significant.

CONCLUSIONS

In this hypothesis-generating study, we found the serum adiponectin level to be an independent predictor of overall survival in a diverse cohort of HCC patients.

IMPACT

Understanding how adipokines affect the HCC outcome may help develop novel treatment and prevention strategies.

Hepatocellular carcinoma in nonalcoholic fatty liver: Role of environmental and genetic factors

Hepatocellular carcinoma (HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoholic fatty liver disease (NAFLD) associated with obesity, insulin resistance, and type 2 diabetes, is an increasingly recognized trigger, especially in developed countries. Older age, severity of insulin resistance and diabetes, and iron overload have been reported to predispose to HCC in this context. Remarkably, HCCs have been reported in non-cirrhotic livers in a higher proportion of cases in NAFLD patients than in other etiologies. Inherited factors have also been implicated to explain the different individual susceptibility to develop HCC, and their role seems magnified in fatty liver, where only a minority of affected subjects progresses to cancer. In particular, the common I148M variant of the PNPLA3 gene influencing hepatic lipid metabolism influences HCC risk independently of its effect on the progression of liver fibrosis. Recently, rare loss-of-function mutations in Apolipoprotein B resulting in very low density lipoproteins hepatic retention and in Telomerase reverse transcriptase influencing cellular senescence have also been linked to HCC in NAFLD. Indeed, hepatic stellate cells senescence has been suggested to bridge tissue aging with alterations of the intestinal microbiota in the pathogenesis of obesity-related HCC. A deeper understanding of the mechanisms mediating hepatic carcinogenesis during insulin resistance, and the identification of its genetic determinants will hopefully provide new diagnostic and therapeutic tools.

Interstrain differences in the progression of nonalcoholic steatohepatitis to fibrosis in mice are associated with altered hepatic iron metabolism

Nonalcoholic fatty liver disease (NAFLD) is a major health problem worldwide. Currently, there is a lack of conclusive information to clarify the molecular events and mechanisms responsible for the progression of NAFLD to fibrosis and cirrhosis and, more importantly, for differences in interindividual disease severity. The aim of this study was to investigate a role of interindividual differences in iron metabolism among inbred mouse strains in the pathogenesis and severity of fibrosis in a model of NAFLD. Feeding male A/J, 129S1/SvImJ and WSB/EiJ mice a choline- and folate-deficient diet caused NAFLD-associated liver injury and iron metabolism abnormalities, especially in WSB/EiJ mice. NAFLD-associated fibrogenesis was correlated with a marked strain- and injury-dependent increase in the expression of iron metabolism genes, especially transferrin receptor (Tfrc), ferritin heavy chain (Fth1), and solute carrier family 40 (iron-regulated transporter), member 1 (Slc40a1, Fpn1) and their related proteins, and pronounced down-regulation of the iron regulatory protein 1 (IRP1), with the magnitude being A/J<129S1/SvImJ<WSB/EiJ. Mechanistically, down-regulation of IRP1 was linked to an increased expression of microRNAs miR-200a and miR-223, which was negatively correlated with IRP1. The results of this study demonstrate that the interstrain variability in the extent of fibrogenesis was associated with a strain-dependent deregulation of hepatic iron homeostasis.

Surveillance for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a dreaded complication of cirrhosis as it is the commonest cause of mortality in these patients. The last few years have seen a dramatic improvement in the management of this tumor as nearly 50-70% of selected patients with early HCC survive for a median period of up to 5 years after liver transplantation, resection or local ablation. Surveillance has been found to be an effective tool to detect early tumors and expand the applicability of these curative treatment options. Semiannual ultrasonogram is recommended for surveillance by the American, European and Asia Pacific liver societies and is the standard of care in many countries. There is increasing evidence that this practice improves survival too. Since the only way to improve the outlook of HCC is its diagnosis prior to commencement of symptoms, providing surveillance becomes a major responsibility of physicians caring for patients with chronic liver disease. This review attempts to discuss the population at risk of HCC, modalities and frequency of surveillance tests, cost effectiveness and also the logistics of its delivery in the Indian context.

Could metabolic syndrome lead to hepatocarcinoma via non-alcoholic fatty liver disease?

It was estimated that from 2002 to 2008 the risk of developing cancer increased a quarter-fold in men and two-fold in women due to excessive BMI. Obesity, metabolic syndrome and type 2 diabetes mellitus are strictly related and are key pathogenetic factors of non-alcoholic fatty liver disease (NAFLD), the most frequent liver disease worldwide. The most important consequence of the "metabolic epidemics" is the probable rise in the incidence of hepatocarcinoma (HCC), and NAFLD is the major causative factor. Adipose tissue is not merely a storage organ where lipids are preserved as an energy source. It is an active organ with important endocrine, paracrine, and autocrine actions in addition to immune functions. Adipocytes produce a wide range of hormones, cytokines, and growth factors that can act locally in the adipose tissue microenvironment and systemically. In this article, the main roles of insulin growth factor (IGF)-1 and IGF-2 are discussed. The role of IGF-2 is not only confined to HCC, but it may also act in early hepato-carcinogenesis, as pre-neoplastic lesions express IGF-2 mRNA. IGF-1 and IGF-2 interact with specific receptors (IGF-1R and IGF-2R). IGF-1R is over-expressed in in vitro and in animal models of HCC and it was demonstrated that IGF ligands exerted their effects on HCC cells through IGF-1R and that it was involved in the degeneration of pre-neoplastic lesions via an increase in their mitotic activity. Both IGF-2R and TGF β, a growth inhibitor, levels are reduced in human HCC compared with adjacent normal liver tissues. Another key mechanism involves peroxisome proliferator-activated receptor (PPAR)γ. In in vitro studies, PPARγ inhibited various carcinomas including HCC, most probably by regulating apoptosis via the p21, p53 and p27 pathways. Finally, as a clinical consequence, to improve survival, efforts to achieve a "healthier diet" should be promoted by physicians and politicians.

Recent Advances in Understanding of NASH: MicroRNAs as Both Biochemical Markers and Players

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatis (NASH) are becoming the dominant liver diseases in the US and Western World. Extensive work is being done to diagnose, understand, and explore the pathogenesis of these multivariable complex diseases. Recently a new avenue of biologic regulation is being explored. MicroRNAs are non-coding RNAs that modulate the expression of multiple genes and have been implicated in multiple diseases. Recently there is a growing body of evidence supporting a significant role of microRNAs in NAFLD pathogenesis and progression to NASH, and hinting at their use as targets, biomarkers and potential therapeutic tools. This review is designed to highlight some of the recent work on a few of the key microRNAs involved in the pathogenesis of NAFLD and NASH.

Hepatocellular carcinoma: surgical perspectives beyond the barcelona clinic liver cancer recommendations

The barcelona clinic liver cancer (BCLC) staging system has been approved as guidance for hepatocellular carcinoma (HCC) treatment guidelines by the main Western clinical liver associations. According to the BCLC classification, only patients with a small single HCC nodule without signs of portal hypertension or hyperbilirubinemia should undergo liver resection. In contrast, patients with intermediate-advanced HCC should be scheduled for palliative therapies, even if the lesion is resectable. Recent studies report good short-term and long-term outcomes in patients with intermediate-advanced HCC treated by liver resection. Therefore, this classification has been criticised because it excludes many patients who could benefit from curative resection. The aim of this review was to evaluate the role of surgery beyond the BCLC recommendations. Safe liver resection can be performed in patients with portal hypertension and well-compensated liver function with a 5-year survival rate of 50%. Surgery also offers good long-term result in selected patients with multiple or large HCCs with a reported 5-year survival rate of over 50% and 40%, respectively. Although macrovascular invasion is associated with a poor prognosis, liver resection provides better long-term results than palliative therapies or best supportive care. Recently, researchers have identified several genes whose altered expression influences the prognosis of patients with HCC. These genes may be useful for classifying the biological behaviour of different tumours. A revision of the BCLC classification should be introduced to provide the best treatment strategy and to ensure the best prognosis in patients with HCC.

[Occult hepatitis B virus infection and hepatocellular carcinoma]

Many studies have suggested that occult HBV infection has a substantial clinical relevance to hepatocellular carcinoma (HCC). Occult HBV infection is an important risk factor for the development of cirrhosis and HCC in patients without HBsAg. As a matter of fact, occult HBV infection is one of the most common causes of crytogenic HCC in endemic areas of HBV. However, there still are controversial issues about the association between occult HBV infection and HCC according to the underlying liver disease. In alcoholic cirrhosis, occult HBV infection may exert synergistic effect on the development of HCC. However, there is insufficient evidence to relate occult HBV infection to hepatocarcinogenesis in non-alcoholic fatty liver disease. In cryptogenic HCC, occult HBV infection may play a direct role in the development of HCC. In order to elucidate the assocciation between occult HBV infection and HCC, underlying liver disease must be specified and larger number of cases must be included in future studies.

Nutrition and metabolism in hepatocellular carcinoma

Hepatocellular carcinoma is the fifth most common human cancer worldwide, with an overall 5-year survival in the range of 10%. In addition to the very substantial role of chronic viral hepatitis in causing hepatocellular carcinoma, nutritional status and specific nutritional factors appear to influence disease risk. This is apparent in the increased risk associated with non-alcoholic hepatic cirrhosis occurring in the context of obesity, the metabolic syndrome, and type 2 diabetes. Specific nutrients and ingested toxins, including ethanol, aflatoxin, microcystins, iron, and possibly components of red meat, also are associated with increased hepatocellular carcinoma risk. Other dietary components, including omega-3 fatty acids and branched chain amino acids, may have protective effects. Recent data further suggest that several metabolic regulatory drugs, including metformin, pioglitazone, and statins, may have the potential to decrease the risk of hepatocellular carcinoma. The available data on these nutritional and metabolic factors in causing hepatocellular carcinoma are reviewed with the goal of identifying the strength of current knowledge and directions for future investigation.

Yttrium-90 radioembolization as a bridge to liver transplantation: a single-institution experience

PURPOSE

To evaluate our experience with the use of yttrium-90 ((90)Y) radioembolization in maintaining potential candidacy and, in some instances, downstaging hepatocellular carcinoma (HCC) that does not meet Milan criteria for liver transplantation.

MATERIALS AND METHODS

A retrospective review of 20 consecutive patients with HCC who were listed to receive a liver transplant and were treated with (90)Y radioembolization as a sole modality for locoregional "bridge" therapy was performed. Demographics, radiographic and pathologic response, survival, and recurrences were examined.

RESULTS

Twenty-two (90)Y treatments were performed in 20 patients before transplantation. Median time from first treatment to transplantation was 3.5 months. HCC in 14 patients met the Milan criteria at the time of the first (90)Y treatment, and HCC in six did not. All cases that originally met the Milan criteria remained within the criteria before transplantation, and two of six patients whose disease did not meet the criteria (33%) had their disease successfully downstaged to meet the criteria. Overall, nine patients (45%) had complete or partial radiologic response to (90)Y radioembolization according to modified Response Evaluation Criteria In Solid Tumors. Complete necrosis of tumor with no evidence of viable tumor on pathologic examination was observed in five patients (36%) whose disease met the Milan criteria.

CONCLUSIONS

Particularly in regions with long wait list times, (90)Y treatment is effective in maintaining tumor size in potential liver transplantation candidates with HCC. In addition, it can also be considered as a downstaging therapy in select patients before transplantation.

Opposite association between diabetes, dyslipidemia, and hepatocellular carcinoma mortality in the middle-aged and elderly

Limited data exist regarding metabolic risk factors for deaths from hepatocellular carcinoma (HCC) in aging individuals. We investigated the association between diabetes, dyslipidemia, and HCC mortality in those aged 40 years or more (middle-aged and elderly). In this prospective cohort study based on nationwide health screening units, we consecutively followed middle-aged and elderly participants who had no chronic hepatitis B or C virus infection and received health screening from January 1 1998 to December 31 2008. There were 235 deaths from HCC among 50,080 individuals, ascertained by validated death certificates and the national death registry. Diabetes (adjusted hazard ratio [HR], 3.38; 95% confidence interval [CI], 2.35 to 4.86) was positively associated with deaths from HCC. However, hypertriglyceridemia (HR, 0.38; 95% CI, 0.26 to 0.55) and hypercholesterolemia (HR, 0.50; 95% CI, 0.37 to 0.67) were inversely associated with HCC mortality. The above significant associations remained in the lag time analyses, applied to check for reverse causation. Metabolic syndrome, as defined by the American Heart Association / National Heart Lung Blood Institute criteria (HR, 0.63; 95% CI, 0.46 to 0.86) or by the International Diabetes Federation criteria (HR, 0.62; 95% CI, 0.43 to 0.89), was inversely associated with deaths from HCC, especially in men.

CONCLUSION

Middle-aged and elderly individuals, once having diabetes, deserve HCC surveillance to reduce HCC mortality. More research is needed to elucidate why having baseline dyslipidemia relates to lower future HCC mortality.

Modeling progressive non-alcoholic fatty liver disease in the laboratory mouse

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the world and its prevalence is rising. In the absence of disease progression, fatty liver poses minimal risk of detrimental health outcomes. However, advancement to non-alcoholic steatohepatitis (NASH) confers a markedly increased likelihood of developing severe liver pathologies, including fibrosis, cirrhosis, organ failure, and cancer. Although a substantial percentage of NAFLD patients develop NASH, the genetic and molecular mechanisms driving this progression are poorly understood, making it difficult to predict which patients will ultimately develop advanced liver disease. Deficiencies in mechanistic understanding preclude the identification of beneficial prognostic indicators and the development of effective therapies. Mouse models of progressive NAFLD serve as a complementary approach to the direct analysis of human patients. By providing an easily manipulated experimental system that can be rigorously controlled, they facilitate an improved understanding of disease development and progression. In this review, we discuss genetically- and chemically-induced models of NAFLD that progress to NASH, fibrosis, and liver cancer in the context of the major signaling pathways whose disruption has been implicated as a driving force for their development. Additionally, an overview of nutritional models of progressive NAFLD is provided.

Increased risk of colorectal malignant neoplasm in patients with nonalcoholic fatty liver disease: a large study

Nonalcoholic fatty liver disease (NAFLD) has been suggested to be a strong risk factor of colorectal benign adenomas and advanced neoplasms. The aim of this large cohort study was to further investigate the prevalence of colorectal malignant neoplasm (CRMN) in patients with NAFLD and determine whether association between NAFLD and CRMN exists. 2,315 community subjects (1,370 males and 945 females) who underwent a routine colonoscopy according to international colorectal cancer screening guideline were recruited. Nature of colorectal lesions determined by biopsy and NAFLD was diagnosed by ultrasound. Binary logistic regression analysis was applied to explore the related associations. Prevalence of CRMN was 29.3% (77/263) in patients with NAFLD, which was significantly higher than 18.0% (369/2,052) in the control group (P<0.05). In addition, malignant neoplasm in NAFLD group occurred more frequently at sigmoid colon than in control group (14.3 vs. 11.9%). The incidence of highly-differentiated colorectal adenocarcinoma in NAFLD group was significantly higher than control group (62.3 vs. 9.8%). Univariate analysis showed that NAFLD had strong association with CRMN (OR 2.043; 95% CI 1.512-2.761; P<0.05). After adjusting for metabolic and other confounding factors, NAFLD remained as an independent risk factor for CRMN (OR 1.868; 95% CI 1.360-2.567; P<0.05). NAFLD was an independent risk factor for CRMN. Sigmoid carcinoma and highly differentiated colorectal adenocarcinoma were more commonly found in NAFLD. (ClinicalTrials.gov number, NCT01657773, website: http://clinicaltrials.gov/ct2/show/NCT01657773?term=zheng+minghua&rank=1 ).

GGPPS1 predicts the biological character of hepatocellular carcinoma in patients with cirrhosis

BACKGROUND

Hepatocellular carcinoma (HCC) has been associated with diabetes and obesity, but a possible connection with the metabolic syndrome (MetS) and its potential interaction with hepatitis and cirrhosis are open to discussion. Our previous investigations have shown that GGPPS1 plays a critical role during hyperinsulinism. In this report, the expression and distribution of GGPPS1 in liver cancer, and its clinical significance were investigated.

METHODS

70 patients with hepatocellular carcinoma (HCC) were included in this study. Three different types of tissues from each HCC patient were assembled immediately after surgical resection: tumor-free tissue >5 cm far from tumor edge (TF), adjacent nonmalignant tissue within 2 cm (AT), and tissue from the tumor (TT). Normal liver tissues from 10 liver transplant donors served as healthy control (HC) while 10 patients with liver cirrhosis as cirrhosis control (CC). The expression and distribution of GGPPS1 were detected by immunohistochemistry, western blots, or real-time PCR. The relationship between the expression of GGPPS1 and clinic pathologic index were analyzed.

RESULTS

We found that GGPPS1 was intensified mainly in the cytoplasm of liver tumor cells. Both the expression of GGPPS1 mRNA and protein were upregulated in TT comparing to AT or TF. Meanwhile, HCC patients with cirrhosis had relative higher expression of GGPPS1. In addition, many pathologic characters show close correlation with GGPPS1, such as tumor stage, vessel invasion, and early recurrence.

CONCLUSION

GGPPS1 may play a critical role during the development of HCC from cirrhosis and is of clinical significance for predicting biological character of HCC.

Targeting the mTOR pathway in hepatocellular carcinoma: current state and future trends

Mechanistic target of rapamycin (mTOR) regulates cell growth, metabolism and aging in response to nutrients, cellular energy stage and growth factors. mTOR is frequently up-regulated in cancer including hepatocellular carcinoma (HCC) and is associated with bad prognosis, poorly differentiated tumors, and earlier recurrence. Blocking mTOR with rapamycin and first generation mTOR inhibitors, called rapalogs, has shown promising reduction of HCC tumor growth in preclinical models. Currently, rapamycin/rapalogs are used in several clinical trials for the treatment of advanced HCC, and as adjuvant therapy in HCC patients after liver transplantation and TACE. A second generation of mTOR pathway inhibitors has been developed recently and is being tested in various clinical trials of solid cancers, and has been used in preclinical HCC models. The results of series of clinical trials using mTOR inhibitors in HCC treatment will emerge in the near future.

Nationwide study of 4741 patients with non-B non-C hepatocellular carcinoma with special reference to the therapeutic impact

OBJECTIVE

To examine the prognostic factors and outcomes after several types of treatments in patients with hepatocellular carcinoma (HCC) negative for hepatitis B surface antigen and hepatitis C antibody, so-called "non-B non-C HCC" using the data of a nationwide survey.

BACKGROUND

The proportion of non-B non-C HCC is rapidly increasing in Japan.

METHODS

A total of 4741 patients with non-B non-C HCC, who underwent hepatic resection (HR, n = 2872), radiofrequency ablation (RFA, n = 432), and transcatheter arterial chemoembolization (TACE, n = 1437) as the initial treatment, were enrolled in this study. The exclusion criteria included extrahepatic metastases and/or Child-Pugh C. Significant prognostic variables determined by a univariate analysis were subjected to a multivariate analysis using a Cox proportional hazard regression model.

RESULTS

The degree of liver damage in the HR group was significantly lower than that in the RFA and TACE groups. The HR and TACE groups had significantly more advanced HCC than the RFA group. The 5-year survival rates after HR, RFA, and TACE were 66%, 49%, and 32%, respectively. Stratifying the survival rates, according to the TNM stage and the Japan Integrated Staging (JIS) score, showed the HR group to have a significantly better prognosis than the RFA group in the stage II and in the JIS scores "1" and "2." The multivariate analysis showed 12 independent prognostic factors. HR offers significant prognostic advantages over TACE and RFA.

CONCLUSIONS

The findings of this large prospective cohort study indicated that HR may be recommended, especially in patients with TNM stage II and JIS scores "1" and "2" of non-B non-C HCC.

Noncirrhotic hepatocellular carcinoma: derivation from hepatocellular adenoma? Clinicopathologic analysis

The majority of hepatocellular carcinomas arise in background chronic liver disease, particularly cirrhosis. The pathogenesis of noncirrhotic hepatocellular carcinomas remains unclear. While malignant transformation reportedly occurs in <15% of hepatocellular adenoma, the prevalence of noncirrhotic hepatocellular carcinomas arising from a pre-existing adenoma is a challenge to study. Cirrhotic hepatocellular carcinoma and hepatocellular adenoma may be subclassified by molecular pathways, but little is known in noncirrhotic hepatocellular carcinoma. We aim to delineate clinical, morphologic and immunohistochemical features of noncirrhotic hepatocellular carcinoma to evaluate for possible derivation from hepatocellular adenoma. We evaluated the clinicopathologic features of 74 noncirrhotic hepatocellular carcinomas from 72 patients for underlying clinical conditions and immunohistochemical markers known to be associated with hepatocellular adenoma. Men were more commonly affected (59%); however, in the <50-year-old group, women predominated (8:1). The age range was wide: 18-83 years; median-64 years. Underlying liver diseases were identified in only 7%; however, 25% had diabetes mellitus, 69% were overweight or obese and 58% had metabolic syndrome. Only 50% of the noncirrhotic hepatocellular carcinoma were encapsulated. As published in hepatocellular adenoma, multifocality and larger tumor size were more common in liver fatty acid-binding protein-negative noncirrhotic hepatocellular carcinoma. Beta-catenin nuclear positivity was uncommon (5%), and was restricted to hepatocellular carcinomas in older men. Serum amyloid A positivity was not restricted to any subtype. In summary, we present the largest series to date examining noncirrhotic hepatocellular carcinoma. We evaluated these with current hepatocellular adenoma subclassification markers for possible associations. Thirty percent of the 74 noncirrhotic hepatocellular carcinoma had some clinical, morphological or immunophenotypical associations currently described in hepatocellular adenoma. Our data also confirm the association of noncirrhotic hepatocellular carcinoma in middle-aged to elderly men, an association with metabolic syndrome, and, as with hepatocellular adenoma, that women predominated in the noncirrhotic hepatocellular carcinoma subjects <50 years of age.

Aggravation of nonalcoholic steatohepatitis by moderate alcohol consumption is associated with decreased SIRT1 activity in rats

Chronic alcohol intake decreases adiponectin and sirtuin 1 (SIRT1) expressions, both of which have been implicated in various biological processes including inflammation, apoptosis and metabolism. We have previously shown that moderate consumption of alcohol aggravates liver inflammation and apoptosis in rats with pre-existing nonalcoholic steatohepatitis (NASH). This study investigated whether moderate alcohol intake alters SIRT1 activity, adiponectin/Adiponectin receptor (AdipoR)-related signaling and lipid metabolism in a pre-existing NASH status. Sprague-Dawley rats were fed with a high-fat diet (71% energy from fat) for 6 weeks to induce NASH then subsequently divided into 2 sub-groups: fed either a modified high-fat diet (HFD, 55% energy from fat) or a modified high-fat alcoholic diet (HFA, 55% energy from fat and 16% energy from ethanol) for an additional 4 weeks. We observed in comparison to HFD group, HFA increased hepatic nuclear SIRT1 protein but decreased its deacetylase activity. SREBP-1c protein expression and FAS mRNA levels were significantly upregulated, while DGAT1/2 and CPT-I mRNA levels were downregulated in the livers of HFA compared to HFD. Although hepatic AdipoR1 decreased, HFA did not alter AdipoR2 and their downstream signaling. There were no significant changes in plasma adiponectin and free fatty acids (FFA), as well as adiponectin expression in adipose tissue between the two groups. The present study indicates that suppression in SIRT1 deacetylase activity contributes to alcohol-exacerbated hepatic inflammation and apoptosis in rats with pre-existing NASH. In addition, moderate alcohol intake did not modulate adiponectin/AdipoR signaling axis in this model.

Characterization of hepatocellular carcinoma related genes and metabolites in human nonalcoholic fatty liver disease

BACKGROUND

The worldwide prevalences of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are estimated to range from 30 to 40 % and 5-17 %, respectively. Hepatocellular carcinoma (HCC) is primarily caused by hepatitis B infection, but retrospective data suggest that 4-29 % of NASH cases will progress to HCC. Currently the connection between NASH and HCC is unclear.

AIMS

The purpose of this study was to identify changes in expression of HCC-related genes and metabolite profiles in NAFLD progression.

METHODS

Transcriptomic and metabolomic datasets from human liver tissue representing NAFLD progression (normal, steatosis, NASH) were utilized and compared to published data for HCC.

RESULTS

Genes involved in Wnt signaling were downregulated in NASH but have been reported to be upregulated in HCC. Extracellular matrix/angiogenesis genes were upregulated in NASH, similar to reports in HCC. Iron homeostasis is known to be perturbed in HCC and we observed downregulation of genes in this pathway. In the metabolomics analysis of hepatic NAFLD samples, several changes were opposite to what has been reported in plasma of HCC patients (lysine, phenylalanine, citrulline, creatine, creatinine, glycodeoxycholic acid, inosine, and alpha-ketoglutarate). In contrast, multiple acyl-lyso-phosphatidylcholine metabolites were downregulated in NASH livers, consistent with observations in HCC patient plasma.

CONCLUSIONS

These data indicate an overlap in the pathogenesis of NAFLD and HCC where several classes of HCC related genes and metabolites are altered in NAFLD. Importantly, Wnt signaling and several metabolites are different, thus implicating these genes and metabolites as mediators in the transition from NASH to HCC.

The association between metabolic syndrome and hepatocellular carcinoma: systemic review and meta-analysis

BACKGROUND

The metabolic syndrome (MetS) and/or its individual components have been linked to the development of cancer. Recent studies have suggested a similar link to hepatocellular carcinoma (HCC). The aim of this study was to evaluate the direction and magnitude of the association between the MetS and HCC.

METHODS

Two reviewers independently conducted a systemic search to identify the available evidence from databases from January 1980 to June 2012. Search terms included "Metabolic syndrome," "insulin resistance syndrome," "metabolic abnormalities" combined with "hepatocellular carcinoma," and "liver cancer." No language restriction was applied to the search. Only studies reporting an effect measure for the association between MetS and HCC were eligible for inclusion. Publication bias was assessed using the Begg and Egger tests, with a visual inspection of funnel plot. All analyses were performed using Comprehensive Meta-analysis version 2 software.

RESULTS

Four studies (3 cohort and 1 case control) with a total of 829,651 participants were included in the analysis. The age range of participants was between 30 and 84 years. The combined analysis showed an overall 81% increased risk of HCC in cases with MetS (relative risk, 1.81; 95% confidence interval, 1.37-2.41). After excluding the single case-control study from analysis, the overall risk ratio remained statistically significant (relative risk, 1.49; 95% confidence interval, 1.27-1.74). Funnel plot inspection, Begg and Egger tests showed no evidence of publication bias for combined analysis.

CONCLUSIONS

Though studies are scarce, currently available epidemiologic data are suggestive of significantly higher risk of HCC among patients with MetS.

AMP-activated protein kinase suppresses the in vitro and in vivo proliferation of hepatocellular carcinoma

AMP-activated protein kinase (AMPK) is a central metabolic sensor and plays an important role in regulating glucose, lipid and cholesterol metabolism. Therefore, AMPK is a key therapeutic target in diabetes. Recent pilot studies have suggested that diabetes drugs may reduce the risk of cancer by affecting the AMPK pathway. However, the association between AMPK and the proliferation of hepatocellular carcinoma (HCC) is unknown. In this study, we investigated the relationship between AMPK activity and the proliferation of HCC in cell lines, nude mice and human clinic samples. We first investigated the relationship between AMPK activity and cell proliferation in two HCC cell lines, PLC/PRF/5 and HepG2, by two AMPK activators, 5-aminoimidazole-4-carboxamide-1-h-D-ribofuranoside (AICAR) and metformain. AICAR and metformin treatment significantly inhibited the proliferation of HCC cells and induced cell cycle arrest at G1-S checkpoint. We then observed that metformin abrogated the growth of HCC xenografts in nude mice. The clinical pathology of AMPK activity in HCC, including cell proliferation, differential grade, tumor size and microvessel density, was studied by using 30 clinical tissue samples. In HCC tissue samples, phosphorylated AMPK was expressed mainly in cytoplasm. AMPK activity decreased significantly in HCC in comparison with paracancerous liver tissues (P<0.05). AMPK activity was negatively correlated with the level of Ki-67 (a marker of cell proliferation), differential degradation and tumor size (P<0.05), but not with microvessel density, hemorrhage or necrosis in HCC. Our findings suggest that AMPK activity inhibits the proliferation of HCC and AMPK might be an effective target for prevention and treatment of HCC.

Non-alcoholic steatohepatitis and hepatocellular carcinoma: implications for lycopene intervention

Increased prevalence of non-alcoholic fatty liver disease (NAFLD) is one of the consequences of the current obesity epidemic. NAFLD is a major form of chronic liver disease that is highly prevalent in obese and overweight adults and children. Nonalcoholic steatohepatitis (NASH) is the severe form of NAFLD, and uncontrolled inflammation as displayed in NASH has been identified as one of the key events in enhancing hepatic carcinogenesis. Lycopene is a non-provitamin A carotenoid and the pigment principally responsible for the characteristic deep-red color of ripe tomato and tomato products, as well as some fruits and vegetables. Lycopene's innate antioxidant and anti-inflammatory properties have generated research interests on its capacity to protect against human diseases that are associated with oxidative stress and inflammation. In addition, differential mechanisms of lycopene metabolism including endogenous cleavage by carotenoid cleavage oxygenases (BCOs), generate lycopene metabolites that may also have significant impact on human disease development. However, it remains to be elucidated as to whether lycopene or its metabolites apolycopenoids have protective effects against obesity-related complications including inflammation and tumorigenesis. This article summarizes the in vivo experiments that elucidated molecular mechanisms associated with obesity-related hepatic inflammation and carcinogenesis. This review also provides an overview of lycopene metabolism, and the molecular pathways involved in the potential beneficial properties of lycopene and apolycopenoids. More research is clearly needed to fully unravel the importance of BCOs in tomato carotenoid metabolism and the consequence on human health and diseases.

(-)-Epigallocatechin-3-gallate suppresses hepatic preneoplastic lesions developed in a novel rat model of non-alcoholic steatohepatitis

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to non-alcoholic steatohepatitis (NASH). NASH, which is accompanied by increased oxidative stress and inflammation in the liver, is associated with hepatic carcinogenesis. Green tea catechins (GTCs) possess anti-oxidant, anti-inflammatory, and cancer-preventive properties. In this study, we investigated whether (-)-epigallocatechin-3-gallate (EGCG), a major component of GTCs, inhibits NAFLD/NASH-related liver tumorigenesis.

METHODS

Male 8-week-old Sprague-Dawley (SD) rats were administered a single intraperitoneal injection of a hepatic carcinogen diethylnitrosamine (DEN, 30 mg/kg body weight) and then fed a high-fat diet (HFD) for 7 weeks. The rats were also provided tap water containing 0.01% or 0.1% EGCG during the experiment.

RESULTS

At sacrifice, the livers of SD rats treated with DEN and HFD exhibited marked development of glutathione S-transferase placental form (GST-P)-positive foci, a hepatic preneoplastic lesion, and this was associated with hepatic steatosis, oxidative stress and inflammation, and hepatocyte proliferation. EGCG administration, however, inhibited the development of GST-P-positive foci by decreasing hepatic triglyceride content, reducing hepatic fibrosis, lowering oxidative stress, attenuating inflammation, and inhibiting excessive hepatocyte proliferation in DEN- and HFD-treated SD rats. These findings suggest that the experimental model of SD rats treated with HFD and DEN, in which histopathological and pathophysiological characteristics of NASH and the development of hepatic premalignant lesions were observed, might facilitate the evaluation of liver tumorigenesis associated with NAFLD/NASH.

CONCLUSIONS

Administering EGCG, a GTC, might serve as an effective chemoprevention modality for NAFLD/NASH-related liver tumorigenesis.

Epidemiology and risk factors of biliary tract and primary liver tumors

Primary liver and biliary tract tumors encompass a range of benign and malignant neoplasms. They consist of histologically distinct types of tumors that arise from and are influenced by hepatocytes, biliary epithelial cells, and mesenchymal cells. Improvements in imaging have allowed the detection and diagnosis of these neoplasms to be refined. Investigation at the histologic, molecular, and genetic levels has allowed neoplasms to be categorized and treated. Epidemiology has improved understanding of geographic, ethnic, gender, and cultural differences that link exposures with cancer risk. This article focuses on the epidemiology of major primary adult liver and biliary tract tumors.

Hepatocarcinogenesis in non-alcoholic fatty liver disease in Japan

In Japan, there has been a gradual increase in cases of non-viral chronic liver diseases, including non-alcoholic fatty liver disease (NAFLD), occurring with hepatocellular carcinoma (HCC). First, a national survey investigating the etiology of HCC in Japan was performed. Among HCCs based on non-viral disease, alcoholic liver disease with HCC accounted for 7.2% of all HCCs, followed by chronic liver disease of unknown etiology with HCC (5.1%) and NAFLD with HCC (2.0%). The clinical characteristics of these three HCC groups were clearly different. In our second analysis, the HCC development rates among liver cirrhosis with NAFLD, alcoholic cirrhosis, and cirrhosis with hepatitis C virus (HCV) were compared. HCC development rates were 11.3%/5 years in NAFLD cirrhosis, 30.5%/5 years in HCV cirrhosis, and 12.5%/5 years in alcoholic cirrhosis, suggesting that the hepatocarcinogenesis in NAFLD and alcoholic liver disease were similar but were lower than that in HCV. Using Cox hazards analysis, older age, higher serum γ-glutamyl transpeptidase level, and higher Child-Pugh score as risk factors of HCC were identified. Finally, clinical data of NAFLD-HCC with the data for HCC with HCV (HCV-HCC) were compared. The percentage of NAFLD-HCC patients with des-gamma-carboxy prothrombin-positive was higher than that with α-fetoprotein-positive. The 5-year survival and recurrence rates for NAFLD-HCC were almost similar to those for HCV-HCC. In Asian countries, the prevalence of NAFLD is increasing. Therefore, elucidating the pathogenesis and clinical features of HCC in patients with NAFLD is indeed an urgent problem.

Hard clinical outcomes in patients with NAFLD

Non-alcoholic fatty liver disease (NAFLD), once regarded as an innocuous condition, is now considered to be the most common cause of chronic liver disease worldwide. Evidence suggests a strong association between NAFLD and other potentially life-threatening diseases. A significant proportion of these patients develops progressive liver injury leading to cirrhosis and hepatocellular carcinoma. Unrecognized NAFLD constitutes a substantial proportion of patients with cryptogenic cirrhosis. Several large community-based studies have found increased mortality in NAFLD patients compared to the expected mortality of the general population of the same age and sex. Cardiovascular disease is an important cause of morbidity and mortality in patients with NAFLD and accounts for up to 30 % of overall death. Cardiovascular mortality does not seem to differ between simple steatosis and non-alcoholic steatohepatitis. NAFLD is associated with increased risk of both hepatic and extra-hepatic malignancy. Malignancy is among the most important causes of death in NAFLD patients. NAFLD is a risk factor for liver cancer even without cirrhosis. The steatotic liver has poor ability to regenerate after volume loss, which may lead to the development of liver failure and increased mortality after extended liver resection. Also, transplantation of steatotic liver results in an increased rate of poor graft function, primary graft non-function, and poorer outcome. There is a high recurrence rate of fatty liver disease in patients transplanted for NASH.

Possible association of hepatitis C virus infection with late-onset psoriasis: a hospital-based observational study

Psoriasis is a chronic inflammatory disease mainly involving the skin and joints, mediated by pro-inflammatory cytokine tumor necrosis factor (TNF)-α. In hepatitis C, continuous inflammation mediated by TNF-α leads to liver cirrhosis and diabetes mellitus. Hence, psoriasis and hepatitis C have pathophysiological factors in common. An epidemiological association between the two conditions has been reported, but no detailed research has yet been performed. Frequency of hepatitis C virus (HCV) infection was assessed in 717 patients with psoriasis and 38 057 with all other dermatological diseases who visited Fukuoka University Hospital in 1998-2011. HCV⁺ and HCV⁻ psoriatic patients were further compared. Frequency of HCV infection was significantly higher in psoriasis (7.5%) than in controls (3.3%) in overall ages. When stratified by age at the first visit, the frequency was significantly higher in patients with psoriasis than in controls aged in their 60s (11.8% vs 6.6%, respectively, P = 0.0215) and 70s (19.5% vs 7.3%, P < 0.0001). HCV⁺ psoriatic patients were significantly older at onset than HCV⁻ ones (median, 54 vs 39 years), stronger male predominance (male/female ratio, 4.4:1), similar family history of psoriasis, higher association of diabetes mellitus and hypertension, and significantly lower body mass index (22.4 ± 2.73 vs 24.2 ± 4.61), in age-stratified (≥ 40 years) analysis. HCV⁺ psoriatic patients were less obese, but still had a higher frequency of diabetes mellitus and hypertension, possibly due to chronic inflammation in the liver and other organs. HCV infection may trigger psoriasis, especially late-onset psoriasis, possibly via overproduction of TNF-α, a common mediator of the two conditions.