Obesity and hepatocellular carcinoma: targeting obesity-related inflammation for chemoprevention of liver carcinogenesis

The role and mechanism of selenium in the prevention and progression of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents the most prevalent form of liver cancer. Despite notable advancements in therapeutic strategies, HCC continues to pose significant public health challenges due to its rising incidence and high mortality rates worldwide. Selenium is an essential trace element that playing a critical role in human health. Recent studies have highlighted its potential preventive and therapeutic benefits in the context of HCC. However, some in vitro and in vivo investigations have yielded inconsistent results, and the mechanisms by which selenium influences HCC are still not completely clear. This review begins by providing an extensive evaluation of the effects and mechanisms of selenium on the primary risk factors associated with HCC, including viral infections, metabolic abnormalities, and lifestyle factors. Subsequently, we outline the roles and mechanisms by which selenium influences the proliferation, metastasis, and immune microenvironment of HCC. Finally, we emphasize the imperative for further investigation into the optimal dosage and forms of selenium, as well as its effects on the HCC microenvironment, to inform the development of effective clinical strategies. This review thus provides a foundational framework for the potential clinical application of selenium in the treatment of HCC.

The multifaceted roles of macrophages in the transition from hepatitis to hepatocellular carcinoma: From mechanisms to therapeutic strategies

Macrophages are central to the progression from hepatitis to hepatocellular carcinoma (HCC), with their remarkable plasticity and ability to adapt to the changing liver microenvironment. Chronic inflammation, fibrosis, and ultimately tumorigenesis are driven by macrophage activation, making them key regulators of liver disease progression. This review explores the diverse roles of macrophages in the transition from hepatitis to HCC. In the early stages of hepatitis, macrophages are essential for pathogen clearance and tissue repair. However, chronic activation leads to prolonged inflammation, which exacerbates liver damage and promotes fibrosis. As the disease progresses to liver fibrosis, macrophages interact with hepatic stellate cells, fostering a pro-tumorigenic microenvironment that supports HCC development. In hepatocarcinogenesis, macrophages contribute to tumor initiation, growth, metastasis, immune evasion, cancer stem cell maintenance, and angiogenesis. Their functional plasticity enables them to adapt to the tumor microenvironment, thereby promoting tumor progression and resistance to therapy. Targeting macrophages represents a promising strategy for preventing and treating HCC. Therapeutic approaches, including reprogramming macrophage phenotypes to enhance anti-tumor immunity, blocking macrophage recruitment and activation, and utilizing nanoparticle-based drug delivery systems, may provide new avenues for combating HCC by modulating macrophage functions and tumor microenvironment dynamics.

Novel perspectives on the link between obesity and cancer risk: from mechanisms to clinical implications

Existing epidemiologic and clinical studies have demonstrated that obesity is associated with the risk of a variety of cancers. In recent years, an increasing number of experimental and clinical studies have unraveled the complex relationship between obesity and cancer risk and the underlying mechanisms. Obesity-induced abnormalities in immunity and biochemical metabolism, including chronic inflammation, hormonal disorders, dysregulation of adipokines, and microbial dysbiosis, may be important contributors to cancer development and progression. These contributors play different roles in cancer development and progression at different sites. Lifestyle changes, weight loss medications, and bariatric surgery are key approaches for weight-centered, obesity-related cancer prevention. Treatment of obesity-related inflammation and hormonal or metabolic dysregulation with medications has also shown promise in preventing obesity-related cancers. In this review, we summarize the mechanisms through which obesity affects the risk of cancer at different sites and explore intervention strategies for the prevention of obesity-associated cancers, concluding with unresolved questions and future directions regarding the link between obesity and cancer. The aim is to provide valuable theoretical foundations and insights for the in-depth exploration of the complex relationship between obesity and cancer risk and its clinical applications.

Association between obesity and liver cancer from 2012 to 2023: Bibliometric analysis and global trends

Incidence rates of liver cancer have increased worldwide in recent decades, making it a major public health problem globally. Obesity can be caused by multiple factors and promotes the development of liver cancer in many ways. Although the research on the association between obesity and liver cancer was previously explored, we first employed bibliometrics to analyze the current research status. From 2012 to 2023, the Web of Science Core Collection database was searched for studies regarding the association between obesity and liver cancer. To evaluate worldwide trends and research hotspots in this topic, bibliometric analysis tools such as VOSviewer, CiteSpace, and R Package were employed. Altogether 233 eligible publications, consisting of 167 articles and 66 reviews, were analyzed. The yearly number of publications and average citation numbers have increased over the last 11 years, particularly the last 6 years. The great majority of published articles on this topic originated from the United States (n = 89, 38.20%), followed by China (n = 60, 25.75%), and England (n = 23, 9.87%). In this subject's research, American scholars embodied considerable production, great prominence, and high academic influence. The most cited article was Yoshimoto, S et al of Japan Science and Technology Agency published in 2013 with a citation number of 1410. We apply bibliometric analysis for the first time in this field, expecting to help scholars efficiently and effectively retrieve the association between obesity and liver cancer.

Investigating the causal association between obesity and risk of hepatocellular carcinoma and underlying mechanisms

Obesity is a global health concern and independent risk factor for cancers including hepatocellular carcinoma (HCC). However, evidence on the causal links between obesity and HCC is limited and inconclusive. This study aimed to investigate the causal relationship between obesity-related traits and HCC risk and explore underlying mechanisms using bioinformatics approaches. Two-sample Mendelian randomization analysis was conducted leveraging publicly available genome-wide association study summary data on obesity traits (body mass index, body fat percentage, waist circumference, waist-to-hip ratio, visceral adipose tissue volume) and HCC. Associations of obesity with primary mechanisms (insulin resistance, adipokines, inflammation) and their effects on HCC were examined. Differentially expressed genes in obesity and HCC were identified and functional enrichment analyses were performed. Correlations with tumor microenvironment (TME) and immunotherapy markers were analyzed. Genetically predicted higher body mass index and body fat percentage showed significant causal relationships with increased HCC risk. Overall obesity also demonstrated causal links with insulin resistance, circulating leptin levels, C-reactive protein levels and risk of severe insulin resistant type 2 diabetes. Four differentially expressed genes (ESR1, GCDH, FAHD2A, DCXR) were common in obesity and HCC. Enrichment analyses indicated their roles in processes like RNA capping, viral transcription, IL-17 signaling and endocrine resistance. They exhibited negative correlations with immune cell infiltration and immunotherapy markers in HCC. Overall obesity likely has a causal effect on HCC risk in Europeans, possibly via influencing primary mechanisms. The identified differentially expressed genes may be implicated in obesity-induced hepatocarcinogenesis through regulating cell cycle, inflammation and immune evasion. Further research on precise mechanisms is warranted.

Obesity, non-alcoholic fatty liver disease and hepatocellular carcinoma: current status and therapeutic targets

Obesity is a global epidemic and overwhelming evidence indicates that it is a risk factor for numerous cancers, including hepatocellular carcinoma (HCC), the third leading cause of cancer-related deaths worldwide. Obesity-associated hepatic tumorigenesis develops from nonalcoholic fatty liver disease (NAFLD), progressing to nonalcoholic steatohepatitis (NASH), cirrhosis and ultimately to HCC. The rising incidence of obesity is resulting in an increased prevalence of NAFLD and NASH, and subsequently HCC. Obesity represents an increasingly important underlying etiology of HCC, in particular as the other leading causes of HCC such as hepatitis infection, are declining due to effective treatments and vaccines. In this review, we provide a comprehensive overview of the molecular mechanisms and cellular signaling pathways involved in the pathogenesis of obesity-associated HCC. We summarize the preclinical experimental animal models available to study the features of NAFLD/NASH/HCC, and the non-invasive methods to diagnose NAFLD, NASH and early-stage HCC. Finally, since HCC is an aggressive tumor with a 5-year survival of less than 20%, we will also discuss novel therapeutic targets for obesity-associated HCC and ongoing clinical trials.

Preoperative prediction of early recurrence of HBV-related hepatocellular carcinoma (≤5 cm) by visceral adipose tissue index

Background

This study aimed to investigate whether visceral adipose tissue index (VATI) is a significant risk factor for the early recurrence (ER) of HBV-related hepatocellular carcinoma (HCC) (≤5 cm) after hepatectomy.

Methods

The recruited cohort patients who were positive for hepatitis B virus, presented with surgically confirmed HCC (≤5 cm) from Army Medical University (internal training cohort: n = 192) and Chongqing Medical University (external validation group: n = 46). We measured VATI, subcutaneous adipose tissue index (SATI) via computed tomography (CT). ER was defined as recurrence within 2 years after hepatectomy. The impact of parameters on outcome after hepatectomy for HCC was analyzed.

Results

Univariate analysis showed that alpha-fetoprotein levels (p = 0.044), body mass index (BMI) (p < 0.001), SATI (p < 0.001), and VATI (p < 0.001) were significantly different between ER and non-ER groups in internal training cohort. Multivariate analysis identified VATI as an independent risk factor for ER (odds ratio = 1.07, 95% confidence interval: 1.047-1.094, p < 0.001), with a AUC of 0.802, based on the cut-off value of VATI, which was divided into high risk (≥37.45 cm²/m²) and low risk (<37.45 cm²/m²) groups. The prognosis of low risk group was significantly higher than that of high risk group (p < 0.001). The AUC value of VATI in external validation group was 0.854.

Conclusion

VATI was an independent risk factor for the ER, and higher VATI was closely related to poor outcomes after hepatectomy for HBV-related HCC (≤5 cm).

Protective effect of D-(-)-quinic acid as food supplement in modulating AMP-activated protein kinase signalling pathway activation in HFD induced obesity

BACKGROUND

Dietary quinic acid given as the nutritional supplement, which may leads to tryptophan and nicotinamide production in the intestinal tract and NAD⁺ precursor which can prevent from the negative consequences of high fat diet (HFD) consumption.

OBJECTIVE

The present study was designed to assess in vivo and in vitro effect of D-(-)-Quinic acid in high-fat diet induced hyperlipidemia in mice.

MATERIAL AND METHODS

Thirty six albino mice were randomly divided in six groups and each group had six mice. Group I, controlled mice given normal pellet diet, Group-II mice, administered with high fat diet (HFD), Group-III mice given standard drug, Atorvastatin (20 mg/kg, p.o.) along with HFD to mice and Group IV, V and VI mice received D-(-)-Quinic acid at a dose of 75, 150 and 300 mg/kg, respectively in separate group along with HFD to mice. After completion of trial (49 days) the animals were sacrificed and evaluated for body weight, organ fat pad weight, and changes in weight of liver, heart and kidney and also for biochemical parameters, expression of adipogenic and inflammation markers in adipose tissues, and histology examination of liver tissue.

RESULTS

In vitro testing results showed, D-(-)-Quinic acid potentially inhibit α-glucosidase enzyme activity as compared to acarbose. The D-(-)-Quinic acid showed significant hypolipidemic activity by decreasing the increased level of cholesterol, triglyceride level, LDL, VLDL and other hepatic parameters like SGOT and SGPT in serum. D-(-)-Quinic acid reduces the mRNA expression level of PPAR-γ2, TNF-α, IL-1β and IL-6 in adipose tissue in hyperlipidemic mice.

Cancer and diabetes: the interlinking metabolic pathways and repurposing actions of antidiabetic drugs

Cancers are regarded as one of the main causes of death and result in high health burden worldwide. The management of cancer include chemotherapy, surgery and radiotherapy. The chemotherapy, which involves the use of chemical agents with cytotoxic actions is utilised as a single treatment or combined treatment. However, these managements of cancer such as chemotherapy poses some setbacks such as cytotoxicity on normal cells and the problem of anticancer drug resistance. Therefore, the use of other therapeutic agents such as antidiabetic drugs is one of the alternative interventions used in addressing some of the limitations in the use of anticancer agents. Antidiabetic drugs such as sulfonylureas, biguanides and thiazolidinediones showed beneficial and repurposing actions in the management of cancer, thus, the activities of these drugs against cancer is attributed to some of the metabolic links between the two disorders and these includes hyperglycaemia, hyperinsulinemia, inflammation, and oxidative stress as well as obesity. Furthermore, some studies showed that the use of antidiabetic drugs could serve as risk factors for the development of cancerous cells particularly pancreatic cancer. However, the beneficial role of these chemical agents overweighs their detrimental actions in cancer management. Hence, the present review indicates the metabolic links between cancer and diabetes and the mechanistic actions of antidiabetic drugs in the management of cancers.

Increased Visceral Adipose Tissue and Hyperinsulinemia Raise the Risk for Recurrence of Non-B Non-C Hepatocellular Carcinoma after Curative Treatment

Simple Summary

With the increasing prevalence of obesity and diabetes in most countries, the increase in hepatocellular carcinoma (HCC) associated with these factors has recently become a serious healthcare problem. HCC can often emerge in the non-cirrhotic liver among obese patients, and it might suggest that the conventional surveillance strategies for HCC, which is mainly targeted at cirrhotic patients with hepatitis B or C virus, might be insufficient in the overnutrition era. We tried to extract factors that affect recurrence-free survival in patients with non-viral HCC, among obesity and diabetes factors, together with the established recurrence risk factors, using a decision-tree analysis.

Abstract

We investigated the factors affecting recurrence-free survival in patients with non-B non-C hepatocellular carcinoma (HCC) who received curative treatment. Decision-tree analysis was performed in 72 curative cases of non-B non-C HCC to extract the risk factors for recurrence. The reliability of the extracted risk factors was evaluated using the Kaplan–Meier method and the Cox proportional hazards model. The decision-tree analysis extracted three factors—visceral adipose tissue (VAT) index (VATI; <71 and ≥71 cm²/m²), which was the cross-sectional areas of VAT on the computed tomographic image at the umbilical level, normalized by the square of the height, fasting immunoreactive insulin (FIRI; <5.5 and ≥5.5 µU/mL), and alpha-fetoprotein (AFP; <11 and ≥11 ng/mL). The Cox proportional hazards model showed that VATI (hazard ratio (HR): 2.556, 95% confidence interval (CI): 1.191–5.486, p = 0.016), FIRI (HR: 3.149, 95% CI: 1.156–8.575, p = 0.025), and AFP (HR: 3.362, 95% CI: 1.550–7.288, p = 0.002) were all independent risk factors for HCC recurrence. Non-B non-C HCC patients with a higher VATI (≥71 cm²/m²) or higher FIRI (≥5.5 µU/mL) and AFP (≥11 ng/mL) if VATI was <71 cm²/m² are prone to recurrence after curative treatment.

Dietary inflammatory index and incidence of and death from primary liver cancer: A prospective study of 103,902 American adults

Chronic inflammation plays an important role in primary liver cancer (PLC) etiology and can be influenced by dietary habits. No prospective study has investigated the association of dietary inflammatory index (DII) with PLC incidence and mortality. Therefore, we used prospective data from the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial to fill this gap. The DII was calculated from a validated 137-item food frequency questionnaire in a cohort of 103,902 individuals. Cox regression was used to estimate hazard ratios (HRs) for PLC incidence, and competing risk regression was used to estimate subdistribution HRs (SHRs) for PLC mortality. Restricted cubic spline regression was employed to identify the potential dose-response pattern. A total of 120 PLC cases and 102 PLC deaths were observed during follow-up. Higher DII scores from food and supplement were found to be associated with higher risks of developing PLC (HR_{Tertile 3 vs. 1} 2.05; 95% confidence interval [CI] 1.23-3.41) and death from this disease (SHR_{Tertile 3 vs. 1} 1.97; 95% CI 1.13-3.41). Similar results were obtained for DII score from food only. A nonlinear dose-response pattern was identified for the aforementioned associations (all p_nonlinearity  < 0.05). Overall, a more pro-inflammatory diet, as suggested by higher DII scores, is associated with higher risks of PLC incidence and mortality. These findings indicate that encouraging intake of more anti-inflammatory dietary components and reducing intake of pro-inflammatory components represent an attractive strategy to reduce PLC incidence and mortality.

Usefulness of Carnitine Supplementation for the Complications of Liver Cirrhosis

Carnitine is a vitamin-like substance that regulates lipid metabolism and energy production. Carnitine homeostasis is mainly regulated by dietary intake and biosynthesis in the organs, including the skeletal muscle and the liver. Therefore, liver cirrhotic patients with reduced food intake, malnutrition, biosynthetic disorder, and poor storage capacity of carnitine in the skeletal muscle and liver are more likely to experience carnitine deficiency. In particular, liver cirrhotic patients with sarcopenia are at a high risk for developing carnitine deficiency. Carnitine deficiency impairs the important metabolic processes of the liver, such as gluconeogenesis, fatty acid metabolism, albumin biosynthesis, and ammonia detoxification by the urea cycle, and causes hypoalbuminemia and hyperammonemia. Carnitine deficiency should be suspected in liver cirrhotic patients with severe malaise, hepatic encephalopathy, sarcopenia, muscle cramps, and so on. Importantly, the blood carnitine level does not always decrease in patients with liver cirrhosis, and it sometimes exceeds the normal level. Therefore, patients with liver cirrhosis should be treated as if they are in a state of relative carnitine deficiency at the liver, skeletal muscle, and mitochondrial levels, even if the blood carnitine level is not decreased. Recent clinical trials have revealed the effectiveness of carnitine supplementation for the complications of liver cirrhosis, such as hepatic encephalopathy, sarcopenia, and muscle cramps. In conclusion, carnitine deficiency is not always rare in liver cirrhosis, and it requires constant attention in the daily medical care of this disease. Carnitine supplementation might be an important strategy for improving the quality of life of patients with liver cirrhosis.

Epigallocatechin-3-Gallate Toxicity in Children: A Potential and Current Toxicological Event in the Differential Diagnosis With Virus-Triggered Fulminant Hepatic Failure

The use of nutraceuticals is considerably increasing worldwide with a demand for organic and clean foods in the last two decades, which is probably incomparable with other periods of our civilization. The consistent application of nutraceuticals and so-called "superfood" may have remarkable effects on the prevention of several chronic diseases, including cancer. Moreover, the increased rate of overweight and obesity in Western countries does not spare childhood and youth, and the number of parents using natural remedies for preventing pediatric illness is vastly increasing worldwide. However, the overwhelming effects on diseases often overshadow the side effects of such nutrition, particularly in societies without millennial experience with botanicals and natural elements. Thus, the final result may be disastrous for some individuals. The liver is the most important and conspicuous target organ of numerous molecular compounds, and the cell damage is particularly striking on the infantile and pediatric liver due to the immaturity of the hepatocytes. Here, we target some generic data on fulminant hepatic failure, the benefits, and toxicity of epigallocatechin-3-gallate, which is one of the major components of green tea, and the histopathology of the "green-tea"-associated liver disease.

Rapid Depletions of Subcutaneous Fat Mass and Skeletal Muscle Mass Predict Worse Survival in Patients with Hepatocellular Carcinoma Treated with Sorafenib

The aim of this study was to investigate whether rapid depletions of fat mass and skeletal muscle mass predict mortality in hepatocellular carcinoma (HCC) patients treated with sorafenib. This retrospective study evaluated 61 HCC patients. The cross-sectional areas of visceral and subcutaneous fat mass and skeletal muscle mass were measured by computed tomography, from which the visceral fat mass index (VFMI), subcutaneous fat mass index (SFMI), and skeletal muscle index (L3SMI) were obtained. The relative changes in these indices per 120 days (ΔVFMI, ΔSFMI, and ΔL3SMI) before and after sorafenib treatment were calculated in each patient. Patients within the 20th percentile cutoffs for these indices were classified into the rapid depletion (RD) group. Kaplan-Meier analysis revealed that with respect to ΔL3SMI (p = 0.0101) and ΔSFMI (p = 0.0027), the RD group had a significantly poorer survival. Multivariate analysis using the Cox proportional-hazards model also demonstrated that ΔL3SMI (≤-5.73 vs. >-5.73; hazard ratio [HR]: 4.010, 95% confidence interval [CI]: 1.799-8.938, p = < 0.001) and ΔSFMI (≤-5.33 vs. >-5.33; HR: 4.109, 95% CI: 1.967-8.584, p = < 0.001) were independent predictors. Rapid depletions of subcutaneous fat mass and skeletal muscle mass after the introduction of sorafenib indicate a poor prognosis.

An inflammatory-CCRK circuitry drives mTORC1-dependent metabolic and immunosuppressive reprogramming in obesity-associated hepatocellular carcinoma

Obesity increases the risk of hepatocellular carcinoma (HCC) especially in men, but the molecular mechanism remains obscure. Here, we show that an androgen receptor (AR)-driven oncogene, cell cycle-related kinase (CCRK), collaborates with obesity-induced pro-inflammatory signaling to promote non-alcoholic steatohepatitis (NASH)-related hepatocarcinogenesis. Lentivirus-mediated Ccrk ablation in liver of male mice fed with high-fat high-carbohydrate diet abrogates not only obesity-associated lipid accumulation, glucose intolerance and insulin resistance, but also HCC development. Mechanistically, CCRK fuels a feedforward loop by inducing STAT3-AR promoter co-occupancy and transcriptional up-regulation, which in turn activates mTORC1/4E-BP1/S6K/SREBP1 cascades via GSK3β phosphorylation. Moreover, hepatic CCRK induction in transgenic mice stimulates mTORC1-dependent G-csf expression to enhance polymorphonuclear myeloid-derived suppressor cell recruitment and tumorigenicity. Finally, the STAT3-AR-CCRK-mTORC1 pathway components are concordantly over-expressed in human NASH-associated HCCs. These findings unveil the dual roles of an inflammatory-CCRK circuitry in driving metabolic and immunosuppressive reprogramming through mTORC1 activation, thereby establishing a pro-tumorigenic microenvironment for HCC development.

Bariatric Surgery and Hepatocellular Carcinoma: a Propensity Score-Matched Analysis

BACKGROUND

The association between obesity and rising incidence of hepatocellular carcinoma (HCC) in the USA has been documented; however, the role of bariatric surgery remains less clear.

AIM

To evaluate the cross-sectional association of prior-bariatric surgery and HCC.

METHODS

The United States Nationwide Inpatient Sample (NIS) database was queried from 2004 to 2014 for discharges with a diagnosis of morbid obesity. Primary outcomes of interest were HCC and in-hospital mortality rate. Secondary outcomes were length of stay and cost. Baseline characteristics were balanced using propensity score matching (PSM). Using Poisson and logistic regressions, adjusted HCC prevalence ratio (PR) and mortality odds ratio (OR) were derived in patients with prior-bariatric surgery compared to those without bariatric surgery.

RESULTS

Of the 2,881,414 patients included in our study, 267,082 (9.3%) underwent bariatric surgery. From 2004 to 2014, there was a threefold increase in age-adjusted prevalence of HCC from 27 per 100,000 to 72 per 100,000 (PTrend < 0.001). After PSM, 230,956 patients with prior-bariatric surgery were matched with 230,956 patients without bariatric surgery. Prior-bariatric surgery was associated with lower prevalence of HCC (PR 0.11; 95% CI, 0.03-0.48; P < 0.001). In-hospital mortality was also lower for patients with surgery (OR 0.22; 95% CI, 0.20-0.26; P < 0.001). The occurrence of HCC added $18,840 extra cost, increased mean length of stay by 2 (95% CI; 1-3) days, and increased risk of death by 65% (aOR 1.65; 95% CI 1.18-2.29).

CONCLUSION

In this nationwide study of morbidly obese patients, prior-bariatric surgery was associated with a lower prevalence of HCC and lower in-patient mortality.

Plasma cholesterol and lipoprotein levels in relation to tumor aggressiveness and survival in HCC patients

BACKGROUND AND AIMS:

Hepatocellular carcinoma is associated with several chronic liver diseases, especially chronic hepatitis B virus, hepatitis C virus, and alcoholism. It is increasingly appreciated that obesity/metabolic syndrome is also associated with chronic liver disease and subsequent hepatocellular carcinoma.

METHODS:

We retrospectively investigated the serum lipid profiles in a large hepatocellular carcinoma cohort, associated predominantly with the hepatitis B virus, hepatitis C virus, alcohol or nonalcoholic steatohepatitis. The cohort was examined both as a whole, as well as stratified by etiology.

RESULTS:

We found significant associations between parameters of hepatocellular carcinoma biology such as maximum tumor diameter, portal vein thrombosis, tumor multifocality or alpha-fetoprotein levels and individual lipid components, including total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides and body mass index. In a final multiple linear regression model considering all lipid variables together, only high-density lipoprotein cholesterol was significantly associated with the tumor Tumor Aggressiveness Index. High-density lipoprotein cholesterol was found to have a statistically higher hazard ratio for death than low high-density lipoprotein cholesterol levels (Cox). On examination by etiological group, alpha-fetoprotein levels were significantly higher in patients with hepatitis C virus compared to those with alcohol or nonalcoholic steatohepatitis, but maximum tumor diameter, tumor multifocality and portal vein thrombosis were similar across etiological groups. Nonalcoholic steatohepatitis patients had significantly less cirrhosis than other groups and hepatitis B virus patients had significantly higher cholesterol and low-density lipoprotein cholesterol levels than hepatitis C virus patients.

CONCLUSIONS:

This is the first report, to our knowledge, of a relationship between serum lipid parameters and indices of hepatocellular carcinoma growth, invasion and aggressiveness, as well as with survival.

Increased visceral fat volume raises the risk for recurrence of hepatocellular carcinoma after curative treatment

Obesity is a risk factor for the development of hepatocellular carcinoma (HCC). This study aimed to assess the influence of visceral fat on the recurrence of HCC after curative treatment. In 207 curative cases of HCC, the cross-sectional areas of visceral and subcutaneous fat mass on the computed tomographic image at the fourth lumbar vertebra were normalized by the square of the height to obtain the visceral fat mass index (VFMI) and the subcutaneous fat mass index (SFMI), respectively. Whether VFMI and SFMI contributed to recurrence of HCC and overall survival was analyzed using a Cox proportional hazards model. Increased VFMI was significantly associated with recurrence of HCC (P = 0.006), whereas SFMI was not (P = 0.502). When the patients were divided based on the optimal cut off value for VFMI (47.2 cm²/m²), obtained from maximally selected rank statistics to best predict the risk for recurrence, the higher VFMI group (n = 79) had more probability of recurrence than the lower VFMI group (n = 128) (log rank test, P = 0.002). There were significant differences in body mass index (P < .0001), SFMI (P < .0001), L3 skeletal muscle index (P < .0001), platelet count (P = 0.003), hemoglobin A1c (P < .0001), triglycerides (P = 0.004), serum leptin (P = 0.043), and underlying liver disease (P < .0001) between the groups. Neither VFMI (P = 0.689) nor SFMI (P = 0.117) significantly contributed to overall survival. VFMI, which is involved in obesity and its related metabolic disorders such as diabetes, hyperlipidemia, and adipokine imbalance, is an extremely promising indicator that can predict the risk of recurrence of HCC after curative treatment.

Combination of Mitochondrial and Plasma Membrane Citrate Transporter Inhibitors Inhibits De Novo Lipogenesis Pathway and Triggers Apoptosis in Hepatocellular Carcinoma Cells

Increased expression levels of both mitochondrial citrate transporter (CTP) and plasma membrane citrate transporter (PMCT) proteins have been found in various cancers. The transported citrates by these two transporter proteins provide acetyl-CoA precursors for the de novo lipogenesis (DNL) pathway to support a high rate of cancer cell viability and development. Inhibition of the DNL pathway promotes cancer cell apoptosis without apparent cytotoxic to normal cells, leading to the representation of selective and powerful targets for cancer therapy. The present study demonstrates that treatments with CTP inhibitor (CTPi), PMCT inhibitor (PMCTi), and the combination of CTPi and PMCTi resulted in decreased cell viability in two hepatocellular carcinoma cell lines (HepG2 and HuH-7). Treatment with citrate transporter inhibitors caused a greater cytotoxic effect in HepG2 cells than in HuH-7 cells. A lower concentration of combined CTPi and PMCTi promotes cytotoxic effect compared with either of a single compound. An increased cell apoptosis and an induced cell cycle arrest in both cell lines were reported after administration of the combined inhibitors. A combination treatment exhibits an enhanced apoptosis through decreased intracellular citrate levels, which consequently cause inhibition of fatty acid production in HepG2 cells. Apoptosis induction through the mitochondrial-dependent pathway was found as a consequence of suppressed carnitine palmitoyl transferase-1 (CPT-1) activity and enhanced ROS generation by combined CTPi and PMCTi treatment. We showed that accumulation of malonyl-CoA did not correlate with decreasing CPT-1 activity. The present study showed that elevated ROS levels served as an inhibition on Bcl-2 activity that is at least in part responsible for apoptosis. Moreover, inhibition of the citrate transporter is selectively cytotoxic to HepG2 cells but not in primary human hepatocytes, supporting citrate-mediating fatty acid synthesis as a promising cancer therapy.

Preventive effects of the sodium glucose cotransporter 2 inhibitor tofogliflozin on diethylnitrosamine-induced liver tumorigenesis in obese and diabetic mice

Sodium glucose cotransporter 2 inhibitors are expected to ameliorate the abnormalities associated with metabolic syndrome including non-alcoholic fatty liver disease. In this study, we investigated the effects of the sodium glucose cotransporter 2 inhibitor tofogliflozin on the development of non-alcoholic fatty liver disease-related liver tumorigenesis in C57BL/KsJ-+Lepr^db/+Lepr^db obese and diabetic mice. The direct effects of tofogliflozin on human liver cancer cell proliferation were also evaluated. Mice were administered diethylnitrosamine-containing water for 2 weeks and were treated with tofogliflozin throughout the experiment. In mice treated with tofogliflozin, the development of hepatic preneoplastic lesions was markedly suppressed, and hepatic steatosis and inflammation significantly reduced, as evaluated using the non-alcoholic fatty liver disease activity score, in comparison with the control mice. Serum levels of glucose and free fatty acid and mRNA expression levels of pro-inflammatory markers in the liver were reduced by tofogliflozin treatment. Conversely, the proliferation of sodium glucose cotransporter 2 protein-expressing liver cancer cells was not inhibited by this agent. These findings suggest that tofogliflozin suppressed the early phase of obesity- and non-alcoholic fatty liver disease-related hepatocarcinogenesis by attenuating chronic inflammation and hepatic steatosis. Therefore, sodium glucose cotransporter 2 inhibitors may have a chemopreventive effect on obesity-related hepatocellular carcinoma.

Sodium alginate prevents progression of non-alcoholic steatohepatitis and liver carcinogenesis in obese and diabetic mice

Obesity and related metabolic abnormalities play a key role in liver carcinogenesis. Non-alcoholic steatohepatitis (NASH), which is often complicated with obesity and diabetes mellitus, is associated with the development of hepatocellular carcinoma (HCC). Sodium alginate (SA), which is extracted from brown seaweeds, is marketed as a weight loss supplement because of its high viscosity and gelling properties. In the present study, we examined the effects of SA on the progression of NASH and related liver carcinogenesis in monosodium glutamate (MSG)-treated mice, which show obesity, diabetes mellitus, and NASH-like histopathological changes. Male MSG-mice were intraperitoneally injected with diethylnitrosamine at 2 weeks of age, and, thereafter, they received a basal diet containing high- or low-molecular-weight SA throughout the experiment (16 weeks). At sacrifice, control MSG-treated mice fed the basal-diet showed significant obesity, hyperinsulinemia, steatosis and hepatic tumor development. SA administration suppressed body weight gain; improved insulin sensitivity, hyperinsulinemia, and hyperleptinemia; attenuated inflammation in the liver and white adipose tissue; and inhibited hepatic lipogenesis and progression of NASH. SA also reduced oxidative stress and increased anti-oxidant enzyme levels in the liver. Development of hepatic tumors, including liver cell adenoma and HCC, and hepatic pre-neoplastic lesions was significantly inhibited by SA supplementation. In conclusion, oral SA supplementation improves liver steatosis, insulin resistance, chronic inflammation, and oxidative stress, preventing the development of liver tumorigenesis in obese and diabetic mice. SA may have ability to suppress steatosis-related liver carcinogenesis in obese and diabetic subjects.

Prevention of Hepatocellular Carcinoma

The epidemiology of hepatocellular carcinoma (HCC) has significantly changed throughout the past decade and will continue to do so in the future as a consequence of effective primary prevention and treatment of virus-related liver diseases. However, other risk factors for HCC are constantly on the rise, including alcoholic liver disease and nonalcoholic fatty liver disease. The knowledge on these and further risk factors associated with an increased risk of HCC provide the opportunity and chance for the development and implementation of successful preventive strategies to decrease the worldwide burden of HCC. This mini-review gives a short overview on current strategies in primary, secondary, and tertiary prevention of HCC.

Increased Gustatory Response Score in Obesity and Association Levels with IL-6 and Leptin

Background. The aim of this study was to investigate the relationship between the circulating IL-6 and leptin levels with taste alteration in young obese patients. Methods. A retrospective case-control study was conducted in thirty obese patients and thirty age- and sex-matched healthy controls. Results. Circulating levels of IL-6 and leptin were significantly increased in obese patients than in controls. However, catalase and ORAC levels were significantly decreased in obese patients compared to controls. Additionally, obese participants had high scores for the detection of fats (gustatory response scores [GRS]; p < 0.001). Moreover, IL-6 and leptin were strongly associated with GRS alteration among patients with GRS 4 (resp., OR =17.5 [95% CI, 1.56–193.32; p = 0.007]; OR = 16 [95% CI, 1.69–151.11; p = 0.006]). For the Mantel-Haenszel common odds ratio estimate (MH OR), IL-6 and leptin were strongly associated with obesity, in patients with either GRS 4 or GRS > 4 (resp., MH OR = 8.77 [95% CI, 2.06–37.44; p = 0.003]; MH OR = 5.76 [95% CI, 1.64–20.24; p = 0.006]). Conclusions. In a low grade inflammation linked to obesity, taste alteration is associated with high levels of IL-6 and leptin.

Preventive effects of astaxanthin on diethylnitrosamine-induced liver tumorigenesis in C57/BL/KsJ-db/db obese mice

AIM

Obesity and its related metabolic abnormalities, including oxidative stress and adipokine imbalance, are involved in liver carcinogenesis. The aim of the present study was to examine the effects of astaxanthin, a powerful biological antioxidant, on the development of diethylnitrosamine (DEN)-induced liver tumorigenesis in C57BL/KsJ-db/db (db/db) obese mice.

METHODS

Male db/db mice were given a single i.p. injection of DEN (25 mg/kg bodyweight) at 2 weeks of age, and, subsequently, from 4 weeks of age, they were fed a diet containing 200 p.p.m. astaxanthin throughout the experiment.

RESULTS

Twenty weeks of astaxanthin administration significantly inhibited the development of hepatocellular neoplasms (liver cell adenoma and hepatocellular carcinoma) and the hepatic expression of cyclin D1 mRNA compared with the basal diet group in DEN-treated db/db mice. Astaxanthin administration in DEN-treated experimental mice markedly reduced the derivatives of reactive oxygen metabolites/biological antioxidant potential ratio, which is a serum marker of oxidative stress, while increasing the mRNA expression of the antioxidant enzymes superoxide dismutase 2 and glutathione peroxidase 1 in the liver and white adipose tissue. The serum levels of adiponectin increased after astaxanthin administration in these mice.

CONCLUSION

Dietary astaxanthin prevented the development of liver tumorigenesis in obese mice by improving oxidative stress and ameliorating serum adiponectin level. Therefore, astaxanthin may be useful in the chemoprevention of liver tumorigenesis in obese individuals.

Hepatocyte-Specific Arid1a Deficiency Initiates Mouse Steatohepatitis and Hepatocellular Carcinoma

ARID1A, encoding a subunit of chromatin remodeling SWI/SNF complexes, has recently been considered as a new type of tumor suppressor gene for its somatic mutations frequently found in various human tumors, including hepatocellular carcinoma (HCC). However, the role and mechanism of inactivated ARID1A mutations in tumorigenesis remain unclear. To investigate the role of ARID1A inactivation in HCC pathogenesis, we generated hepatocyte-specific Arid1a knockout (Arid1a^LKO) mice by crossing mice carrying loxP-flanked Arid1a exon 8 alleles (Arid1a^f/f) with albumin promoter-Cre transgenic mice. Significantly, the hepatocyte-specific Arid1a deficiency results in mouse steatohepatitis and HCC development. In Arid1a^LKO mice, we found that innate immune cells, including F4/80+ macrophages and CD11c+ neutrophil cells, infiltrate into the liver parenchyma, accompanied by the increased tumor necrosis factor (TNF)-α and interleukin (IL)-6, and activation of STAT3 and NF-κB pathways. In conclusion, hepatocyte-specific Arid1a deficiency could lead to mouse steatohepatitis and HCC development. This study provides an alternative mechanism by which Arid1a deficiency contributes to HCC tumorigenesis.

Metformin suppresses diethylnitrosamine-induced liver tumorigenesis in obese and diabetic C57BL/KsJ-+Leprdb/+Leprdb mice

Obesity and related metabolic disorders, such as diabetes mellitus, raise the risk of liver carcinogenesis. Metformin, which is widely used in the treatment of diabetes, ameliorates insulin sensitivity. Metformin is also thought to have antineoplastic activities and to reduce cancer risk. The present study examined the preventive effect of metformin on the development of diethylnitrosamine (DEN)-induced liver tumorigenesis in C57BL/KsJ-+Lepr^db/+Lepr^db (db/db) obese and diabetic mice. The mice were given a single injection of DEN at 2 weeks of age and subsequently received drinking water containing metformin for 20 weeks. Metformin administration significantly reduced the multiplicity of hepatic premalignant lesions and inhibited liver cell neoplasms. Metformin also markedly decreased serum levels of insulin and reduced insulin resistance, and inhibited phosphorylation of Akt, mammalian target of rapamycin (mTOR), and p70S6 in the liver. Furthermore, serum levels of leptin were decreased, while those of adiponectin were increased by metformin. These findings suggest that metformin prevents liver tumorigenesis by ameliorating insulin sensitivity, inhibiting the activation of Akt/mTOR/p70S6 signaling, and improving adipokine imbalance. Therefore, metformin may be a potent candidate for chemoprevention of liver tumorigenesis in patients with obesity or diabetes.

Nonalcoholic fatty liver disease, metabolic risk factors, and hepatocellular carcinoma: an open question

Non-alcoholic liver disease (NAFLD) defines liver abnormalities ranging from simple steatosis to nonalcoholic steatohepatitis with or without cirrhosis development, occurring in the absence of significant alcohol consumption, use of teratogenic medication, or hereditary disorders. The association between NAFLD and metabolic syndrome is well documented and widely recognized. Obesity, type 2 diabetes mellitus (T2DM), and dyslipidemia are the most common metabolic risk factors associated with NAFLD. Among the components of metabolic syndrome, current evidence strongly indicates obesity and diabetes as hepatocellular carcinoma (HCC) risk factors. There is also growing evidence that suggests an increased risk of HCC in NAFLD patients, even surpassing other etiologies in some high-income countries. Epidemiologic data demonstrate a parallel rise in prevalence of obesity, diabetes, NAFLD, and HCC. As obesity and its related diseases have steadily afflicted larger populations, HCC incidence is expected to increase in the future. Pathophysiologic mechanisms that underlie NAFLD development and subsequent progression to nonalcoholic steatohepatitis and cirrhosis (insulin resistance and hyperinsulinemia, oxidative stress, hepatic stellate cell activation, cytokine/adipocytokine signaling pathways, and genetic and environmental factors) appear to play a significant role in the development of NAFLD-related HCC. However, a comprehensive view of molecular mechanisms linking obesity, T2DM, and NAFLD-related HCC, as well as the exact sequence of molecular events, is still not understood in its entirety. Good-quality data are still necessary, and efforts should continue towards better understanding the underlying carcinogenic mechanisms of NAFLD-related HCC. In this paper, we aimed to centralize the most important links supporting these relationships, focusing on obesity, T2DM, and NAFLD-related HCC, as well as point out the major gaps in knowledge regarding the underlying molecular mechanisms behind them.

Chemopreventive potential of green tea catechins in hepatocellular carcinoma

Hepatocellular carcinoma (HCC), which is a common malignancy worldwide, usually develops in a cirrhotic liver due to hepatitis virus infection. Metabolic syndrome, which is frequently complicated by obesity and diabetes mellitus, is also a critical risk factor for liver carcinogenesis. Green tea catechins (GTCs) may possess potent anticancer and chemopreventive properties for a number of different malignancies, including liver cancer. Antioxidant and anti-inflammatory activities are key mechanisms through which GTCs prevent the development of neoplasms, and they also exert cancer chemopreventive effects by modulating several signaling transduction and metabolic pathways. Furthermore, GTCs are considered to be useful for the prevention of obesity- and metabolic syndrome-related carcinogenesis by improving metabolic disorders. Several interventional trials in humans have shown that GTCs may ameliorate metabolic abnormalities and prevent the development of precancerous lesions. The purpose of this article is to review the key mechanisms by which GTCs exert chemopreventive effects in liver carcinogenesis, focusing especially on their ability to inhibit receptor tyrosine kinases and improve metabolic abnormalities. We also review the evidence for GTCs acting to prevent metabolic syndrome-associated liver carcinogenesis.

Skeletal muscle depletion is an independent prognostic factor for hepatocellular carcinoma

BACKGROUND

Skeletal muscle depletion or sarcopenia has been identified as a poor prognostic factor for various diseases. The aim of this study is to determine whether muscle depletion is a prognostic factor for hepatocellular carcinoma (HCC).

METHODS

We evaluated 217 consecutive patients with primary HCC. The skeletal muscle cross-sectional area was measured by computed tomography at the third lumbar vertebra (L3), from which the total body fat-free mass (FFM) and L3 skeletal muscle index (L3 SMI) were obtained. The factors contributing to overall survival (OS) were analyzed by univariate and multivariate Cox proportional hazards model.

RESULTS

In univariate analysis, FFM (P = 0.0422), Child-Pugh classification (P = 0.0058), serum albumin level (P < 0.0001), serum AFP level (P < 0.0001), serum proteins induced by vitamin K absence or antagonist-II level (P < 0.0001), cancer stage (P < 0.0001), and curability of the initial treatment (P < 0.0001) were significantly associated with the prognosis of HCC. Multivariate analysis indicated that FFM (P = 0.0499), albumin level (P = 0.0398), and curability of the initial treatment (P = 0.0008) were independent prognostic factors. Sarcopenia was defined as an L3 SMI value of ≤29.0 cm(2)/m(2) for women and ≤36.0 cm(2)/m(2) for men, and 24 patients (11.1%) have sarcopenia. Sarcopenic patients showed a significantly lower OS than those without sarcopenia (P = 0.0043). Sarcopenic patients who were overweight (BMI >22) died earlier (P = 0.0129).

CONCLUSIONS

Skeletal muscle depletion is an independent prognostic factor. Intervention to prevent muscle wasting might be an effective strategy for improving the outcome of HCC.

Effect of aging, glucose level, and HIV viral load on response to treatment with pegylated interferon plus ribavirin in HIV/HCV co-infected women

BACKGROUND

This was a post-hoc analysis of the Optimized Pegylated interferons Efficacy and anti-Retroviral Approach (OPERA) study, originally designed to document routine clinical and treatment data in HIV/HCV coinfected patients treated with pegylated interferon/ribavirin (PEG-IFN/RBV). The aim of this study was to define the impact of several variables, such as age, glucose metabolism, and HIV viral load, on PEG-IFN/RBV treatment outcomes, in HIV/HCV coinfected women.

METHODS

Female subjects from the OPERA database were retrospectively evaluated and factors associated with sustained virological response (SVR) were assessed and compared to the male population by logistic regression analysis. At baseline, clinical and demographic data were collected. Patients were then administered with PEG-IFN/RBV therapy for 48 weeks. After a 24-week follow-up period, SVR was evaluated.

RESULTS

A total of 1523 patients were enrolled in 98 centers across Italy, 1284 of whom were IFN therapy naïve and were included in the post-hoc analysis. In the female group, factors associated with SVR were the presence of HCV genotype 2,3 (adjusted odds ratio [AOR]=6.87, p<0.0001), age ≤45 years (AOR=2.61, p=0.014), ≥80% exposure to PEG-IFN (AOR=3.85, p=0.019) and RBV (AOR=3.94, p=0.015) therapy. Also, increased glucose plasma level negatively correlated with SVR (AOR=0.98, p=0.066). In the male population, undetectable HIV-RNA (AOR=1.47, p=0.033) but not glucose level (AOR=1.0, p=0.95) predicted SVR.

CONCLUSIONS

Findings from the present study demonstrate that several factors may be predictive of SVR when pegylated interferon plus ribavirin is used (i.e., age, gender, HIV viral load and HCV genotype) that need to be carefully considered prior to therapeutic intervention, since they may hinder successful therapy. Use of PEG-IFN/RBV with novel direct antiviral agents will likely be still maintained until less expensive and effective interferon-free strategies become available.

Hepatic expression of the Sptlc3 subunit of serine palmitoyltransferase is associated with the development of hepatocellular carcinoma in a mouse model of nonalcoholic steatohepatitis

The molecular mechanisms underlying the progression of nonalcoholic steatohepatitis (NASH) have not been fully elucidated. The aim of this study was to identify factors involved in NASH progression by analysis of pathophysiological features and gene-expression profiles in livers of STAM mice, a model of NASH-associated hepatocarcinogenesis. C57BL/6N (B6N) mice were injected with streptozotocin to generate STAM mice. Four-week-old male STAM and B6N mice were fed a high-fat diet (HFD) (STAM-F, B6N-F) or a conventional diet (STAM-C, B6N-C) until they were 10, 14, or 18 weeks old. Blood glucose and nonalcoholic fatty liver disease (NAFLD) activity scores of STAM-F were higher than those of STAM-C during all observation periods. STAM-F mice had more severe hepatic fibrosis at 14 weeks, and exhibited higher levels of α-fetoprotein-positive hepatic tumor formation with multiplication than STAM-C mice at 18 weeks. At 14 weeks, cDNA microarray analysis revealed that the hepatic expression of eight mRNAs was ≥30-fold higher in STAM-F than B6N-F mice. The expression of another four genes was increased ≥5-fold in STAM-F than B6N-F mice, and ≥5-fold in B6N-F relative to B6N-C mice. Of the 12 genes, the difference in Sptlc3 mRNA expression was most pronounced, and gradually increased over time, as determined by quantitative RT-PCR in STAM-F mice. In addition, Sptlc3 mRNA expression in STAM-F mice was higher than that in db/db mice that received HFD and in B6N mice fed a choline‑deficient L-amino acid (CDAA)-defined diet. In conclusion, a high-fat diet aggravated pathophysiological findings in the liver in NASH mouse models, and the hepatic expression of Sptlc3 mRNA was potentially associated with NASH progression.

Diet, sleep and metabolic syndrome among a legal Amazon population, Brazil

Metabolic syndrome incidence is increasing worldwide then it is important to study the possible risk and protective factors. Our previous study suggested an association between coffee consumption and metabolic syndrome. The aim of this study was to address possible associations between dietary lifestyle factors with metabolic syndrome. In a case-control study we compared 74 metabolic syndrome patients with 176-matched controls attended at a public health central unit. Incident cases diagnosed according to ATP III criteria were matched with control group composed of healthy subjects performing routine examinations. Having lower educational level compared to highest levels tend to increase metabolic syndrome prevalence, which was not statistically significant. Similar pattern was observed for marital status. No difference was found regarding gender and metabolic syndrome odds. Interestingly, daily drinking two to three cups of coffee (OR=0.0646, 95% CI, 0.0139-0.3005, p=0.0005) or until 2 cups of milk were inversely associated with metabolic syndrome odds (OR=0.5368, 95% CI, 0.3139-0.9181, p=0.0231). Sleeping seven to eight hours per night was also associated with decreased odds of metabolic syndrome (OR=0.0789, 95% CI, 0.0396-0.1570, p<0.0001). Eating at least two portions of chocolate was also associated with decreased risk of metabolic syndrome (OR=0.3475, 95%CI, 0.1865-0.6414, p=0.0009). Adequate sleeping and dietary intake of some foods materially decreased the metabolic syndrome.

Epidemiology of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common histologic type of primary liver cancer, accounting for between 85% and 90% of these malignancies. The overall prognosis of patients with liver cancer is poor, and an understanding of this disease and its risk factors is crucial for screening at-risk individuals, early recognition, and timely diagnosis. Most HCCs arise in the background of chronic liver disease caused by hepatitis B virus, hepatitis C virus, and chronic excessive alcohol intake. These underlying causes are characterized by marked variations in geography, gender, and other well-documented risk factors, some of which are potentially preventable.

The role of inflammation and liver cancer

Persistent inflammation is known to promote and exacerbate malignancy. Primary liver cancer, mostly hepatocellular carcinoma (HCC), is a clear example of inflammation-related cancer as more than 90 % of HCCs arise in the context of hepatic injury and inflammation. HCC represents the fifth most common malignancy and the third leading cause of cancer-related death worldwide with about one million new cases diagnosed every year with almost an equal number of deaths. Chronic unresolved inflammation is associated with persistent hepatic injury and concurrent regeneration, leading to sequential development of fibrosis, cirrhosis, and eventually HCC. Irrespective of the intrinsic differences among various etiological factors, a common denominator at the origin of HCC is the perpetuation of a wound-healing response activated by parenchymal cell death and the resulting inflammatory cascade. Hence, the identification of fundamental inflammatory signaling pathways causing transition from chronic liver injury to dysplasia and HCC could depict new predictive biomarkers and targets to identify and treat patients with chronic liver inflammation. This chapter critically discusses the roles of several major cytokines, chemokines, growth factors, transcription factors, and enzymes as well as a distinct network of inflammatory signaling pathways in the development and progression of HCC. It also highlights and analyzes preclinical animal studies showing innovative approaches of targeting inflammatory mediators and signaling by a variety of natural compounds and synthetic agents to achieve effective therapy as well as prevention of hepatic malignancy. Additionally, current limitations and potential challenges associated with the inhibition of inflammatory signaling as well as future directions of research to accelerate clinical development of anti-inflammatory agents to prevent and treat liver cancer are presented.

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.

Impact of serum chemerin levels on liver functional reserves and platelet counts in patients with hepatocellular carcinoma

Obesity-related metabolic abnormalities, including adipokine imbalance and chronic inflammation, are involved in liver carcinogenesis. Chemerin, a novel adipokine, plays a critical role in adipogenesis, energy metabolism, and inflammation. We evaluated the impact of serum chemerin levels on liver functional reserves in hepatocellular carcinoma (HCC) patients and on the recurrence and prognosis of HCC. This study included 44 patients with any stage of HCC who underwent curative treatment at Gifu Municipal Hospital (Gifu, Japan) between 2006 and 2007. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Serum albumin levels (Pearson’s correlation coefficient; r = 0.3110, p = 0.0399), platelet counts (r = 0.4159, p = 0.0050), and prothrombin times (r = 0.3775, p = 0.0115) were significantly correlated with serum chemerin levels in patients with HCC, and they were inversely correlated with Child-Pugh scores (r = −0.3732, p = 0.0126), serum alanine aminotransferase levels (r = −0.3864, p = 0.0105), and total bilirubin levels (r = −0.4023, p = 0.0068). Among these variables, a multiple comparison test identified that platelet counts and total bilirubin levels were associated with serum chemerin levels (p < 0.0083). No significant correlation was found between serum chemerin levels and recurrence-free survival (p = 0.3691) or overall survival (p = 0.7916). In HCC patients, serum chemerin concentrations were correlated with liver functional reserves and platelet counts, but not with recurrence or prognosis.

A review of the application of inflammatory biomarkers in epidemiologic cancer research

Inflammation is a facilitating process for multiple cancer types. It is believed to affect cancer development and progression through several etiologic pathways, including increased levels of DNA adduct formation, increased angiogenesis, and altered antiapoptotic signaling. This review highlights the application of inflammatory biomarkers in epidemiologic studies and discusses the various cellular mediators of inflammation characterizing the innate immune system response to infection and chronic insult from environmental factors. Included is a review of six classes of inflammation-related biomarkers: cytokines/chemokines, immune-related effectors, acute-phase proteins, reactive oxygen and nitrogen species, prostaglandins and cyclooxygenase-related factors, and mediators such as transcription factors and growth factors. For each of these biomarkers, we provide a brief overview of the etiologic role in the inflammation response and how they have been related to cancer etiology and progression within the literature. We provide a discussion of the common techniques available for quantification of each marker, including strengths, weaknesses, and potential pitfalls. Subsequently, we highlight a few under-studied measures to characterize the inflammatory response and their potential utility in epidemiologic studies of cancer. Finally, we suggest integrative methods for future studies to apply multifaceted approaches to examine the relationship between inflammatory markers and their roles in cancer development.

Nutrition and exercise in the management of liver cirrhosis

Liver cirrhosis (LC) patients often have protein-energy malnutrition (PEM) and decreased physical activity. These conditions often lead to sarcopenia, which is the loss of skeletal muscle volume and increased muscle weakness. Recent studies have demonstrated that PEM and sarcopenia are predictors for poor survival in LC patients. Nutrition and exercise management can improve PEM and sarcopenia in those patients. Nutrition management includes sufficient dietary intake and improved nutrient metabolism. With the current high prevalence of obesity, the number of obese LC patients has increased, and restriction of excessive caloric intake without the exacerbation of impaired nutrient metabolism is required for such patients. Branched chain amino acids are good candidates for supplemental nutrients for both obese and non-obese LC patients. Exercise management can increase skeletal muscle volume and strength and improve insulin resistance; however, nutritional status and LC complications should be assessed before an exercise management regimen is implemented in LC patients. The establishment of optimal exercise regimens for LC patients is currently required. In this review, we describe nutritional status and its clinical impact on the outcomes of LC patients and discuss general nutrition and exercise management in LC patients.

Bile acid dysregulation, gut dysbiosis, and gastrointestinal cancer

Because of increasingly widespread sedentary lifestyles and diets high in fat and sugar, the global diabetes and obesity epidemic continues to grow unabated. A substantial body of evidence has been accumulated which associates diabetes and obesity to dramatically higher risk of cancer development, particularly in the liver and gastrointestinal tract. Additionally, diabetic and obese individuals have been shown to suffer from dysregulation of bile acid (BA) homeostasis and dysbiosis of the intestinal microbiome. Abnormally elevated levels of cytotoxic secondary BAs and a pro-inflammatory shift in gut microbial profile have individually been linked to numerous enterohepatic diseases including cancer. However, recent findings have implicated a detrimental interplay between BA dysregulation and intestinal dysbiosis that promotes carcinogenesis along the gut-liver axis. This review seeks to examine the currently investigated interactions between the regulation of BA metabolism and activity of the intestinal microbiota and how these interactions can drive cancer formation in the context of diabesity. The precarcinogenic effects of BA dysregulation and gut dysbiosis including excessive inflammation, heightened oxidative DNA damage, and increased cell proliferation are discussed. Furthermore, by focusing on the mediatory roles of BA nuclear receptor farnesoid x receptor, ileal transporter apical sodium dependent BA transporter, and G-coupled protein receptor TGR5, this review attempts to connect BA dysregulation, gut dysbiosis, and enterohepatic carcinogenesis at a mechanistic level. A better understanding of the intricate interplay between BA homeostasis and gut microbiome can yield novel avenues to combat the impending rise in diabesity-related cancers.

Signaling pathways in hepatocellular carcinoma

Hepatocellular carcinoma is a complex multistep process involving progressive abnormalities of hepatocellular survival, proliferation, apoptosis and differentiation. Currently, accumulating evidence has demonstrated that the development of hepatocellular carcinoma is closely associated with dysregulation of several signaling pathways. Aberrant activation of these signaling cascades often leads to the over-expression of oncogenes and down-regulation of tumor suppressor genes, thus promoting cell cycle progression and apoptosis evasion. Here, we discuss some signaling pathways in hepatocellular carcinoma.

(-)-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.

Pharmaceutical and nutraceutical approaches for preventing liver carcinogenesis: chemoprevention of hepatocellular carcinoma using acyclic retinoid and branched-chain amino acids

The poor prognosis for patients with hepatocellular carcinoma (HCC) is associated with its high rate of recurrence in the cirrhotic liver. Therefore, more effective strategies need to be urgently developed for the chemoprevention of this malignancy. The malfunction of retinoid X receptor α, a retinoid receptor, due to phosphorylation by Ras/mitogen-activated protein kinase is closely associated with liver carcinogenesis and may be a promising target for HCC chemoprevention. Acyclic retinoid (ACR), a synthetic retinoid, can prevent HCC development by inhibiting retinoid X receptor α phosphorylation and improve the prognosis for this malignancy. Supplementation with branched-chain amino acids (BCAA), which are used to improve protein malnutrition in patients with liver cirrhosis, can also reduce the risk of HCC in obese cirrhotic patients. In experimental studies, both ACR and BCAA exert suppressive effects on HCC development and the growth of HCC cells. In particular, combined treatment with ACR and BCAA cooperatively inhibits the growth of HCC cells. Furthermore, ACR and BCAA inhibit liver tumorigenesis associated with obesity and diabetes, both of which are critical risk factors for HCC development. These findings suggest that pharmaceutical and nutraceutical approaches using ACR and BCAA may be promising strategies for preventing HCC and improving the prognosis of this malignancy.

Non-B, non-C hepatocellular carcinoma (Review)

Although most hepatocellular carcinoma (HCC) is related to viral infection, there is a substantial population of HCC patients (5-20%) who are negative for both markers of hepatitis B virus and hepatitis C virus infection [non-B, non-C (NBNC) hepatitis] in Japan and the incidence of NBNC-HCC has recently tended to increase. The most common cause of liver disease in developed countries is non‑alcoholic fatty liver disease (NAFLD), which includes non‑alcoholic steatohepatitis (NASH) and its related complications. Increased body mass index and diabetes mellitus are associated with developing NAFLD and NASH, which is a severe form of NAFLD. Furthermore, increasing clinical evidence supports the fact that NAFLD and NASH can progress to liver cirrhosis and even HCC. A detailed understanding of the epidemiology, etiology, molecular mechanism, clinical features and prognosis of NBNC-HCC could improve our screening and therapy of this disease. In this review, we primarily focus on clinical aspects of NBNC-HCC and refer to our current knowledge of this cancer.

Mouse models for liver cancer

Hepatocellular carcinoma (HCC), the most common form of primary liver cancer is the third leading cause of cancer-related cell death in human and the fifth in women worldwide. The incidence of HCC is increasing despite progress in identifying risk factors, understanding disease etiology and developing anti-viral strategies. Therapeutic options are limited and survival after diagnosis is poor. Therefore, better preventive, diagnostic and therapeutic tools are urgently needed, in particular given the increased contribution from systemic metabolic disease to HCC incidence worldwide. In the last three decades, technological advances have facilitated the generation of genetically engineered mouse models (GEMMs) to mimic the alterations frequently observed in human cancers or to conduct intervention studies and assess the relevance of candidate gene networks in tumor establishment, progression and maintenance. Because these studies allow molecular and cellular manipulations impossible to perform in patients, GEMMs have improved our understanding of this complex disease and represent a source of great potential for mechanism-based therapy development. In this review, we provide an overview of the current state of HCC modeling in the mouse, highlighting successes, current challenges and future opportunities.