Chemoprevention of obesity-related liver carcinogenesis by using pharmaceutical and nutraceutical agents

High-Fat Diet Delays Liver Fibrosis Recovery and Promotes Hepatocarcinogenesis in Rat Liver Cirrhosis Model

More effective treatments for hepatitis viral infections have led to a reduction in the incidence of liver cirrhosis. A high-fat diet can lead to chronic hepatitis and liver fibrosis, but the effects of lipid intake on liver disease status, including hepatitis C virus and alcohol, after elimination of the cause are unclear. To investigate the effects, we used a rat cirrhosis model and a high-fat diet in this study. Male Wistar rats were administered carbon tetrachloride for 5 weeks. At 12 weeks of age, one group was sacrificed. The remaining rats were divided into four groups according to whether or not they were administered carbon tetrachloride for 5 weeks, and whether they were fed a high-fat diet or control diet. At 12 weeks of age, liver fibrosis became apparent and then improved in the groups where carbon tetrachloride was discontinued, while it worsened in the groups where carbon tetrachloride was continued. Liver fibrosis was notable in both the carbon tetrachloride discontinuation and continuation groups due to the administration of a high-fat diet. In addition, liver precancerous lesions were observed in all groups, and tumor size and multiplicity were higher in the high-fat diet-fed groups. The expression of genes related to inflammation and lipogenesis were upregulated in rats fed a high-fat diet compared to their controls. The results suggest that a high-fat diet worsens liver fibrosis and promotes liver carcinogenesis, presumably through enhanced inflammation and lipogenesis, even after eliminating the underlying cause of liver cirrhosis.

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.

Combined screening analysis of aberrantly methylated-differentially expressed genes and pathways in hepatocellular carcinoma

BACKGROUND

Methylation plays an important role in hepatocellular carcinoma (HCC) by altering the expression of key genes. The aim of this study was to screen the aberrantly methylated-differentially expressed genes (DEGs) in HCC and elucidate their underlying molecular mechanism.

METHODS

Gene expression microarrays (GSE101685) and gene methylation microarrays (GSE44909) were selected. DEGs and differentially methylated genes (DMGs) were screened. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed using the Database for Annotation, Visualization, and Integrated discovery (DAVID). The Search Tool for the Retrieval of Interacting Genes (STRING) database was used to analyze the functional protein-protein interaction (PPI) network. Molecular Complex Detection (MCODE) analysis was performed using the Cytoscape software. Hub genes were verified in The Cancer Genome Atlas (TCGA) database.

RESULTS

A total of 80 hypomethylation-high expression genes (Hypo-HGs) were identified. Pathway enrichment analysis showed DNA replication, cell cycle, viral carcinogenesis, and the spliceosome. The top 5 hub genes were minichromosome maintenance complex component 3 (MCM3), checkpoint kinase 1 (CHEK1), kinesin family member 11 (KIF11), PDZ binding kinase (PBK), and Rac GTPase activating protein 1 (RACGAP1). In addition, 189 hypermethylation-low expression genes (Hyper-LGs) were identified. Pathway enrichment analysis indicated enrichment in metabolic pathways, drug metabolism-other enzymes, and chemical carcinogenesis. The top 5 hub genes were leukocyte immunoglobulin like receptor B2 (LILRB2), formyl peptide receptor 1 (FPR1), S100 calcium binding protein A9 (S100A9), S100 calcium binding protein A8 (S100A8), and myeloid cell nuclear differentiation antigen (MNDA). The methylation status and mRNA expression of MCM3, CHEK1, KIF11, PBK, and S100A9 were consistent in the TCGA database and significantly correlated with the prognosis of patients.

CONCLUSIONS

Combined screening of aberrantly methylated-DEGs based on bioinformatic analysis may provide new clues for elucidating the epigenetic mechanism in HCC. Hub genes, including MCM3, CHEK1, KIF11, PBK, and S100A9, may serve as biomarkers for the precise diagnosis of HCC.

Hepatocellular carcinoma in non-alcohol fatty liver disease - changing trends and specific challenges

Background and Aims: Hepatocellular carcinoma (HCC) is the most common primary liver cancer. The etiology of this disease is known in 90% of the patients, and it is viral in most of the cases. According to recent predictions, nearly half of the world population will be suffering from obesity by 2030. Consequently, non-alcoholic fatty liver disease (NAFLD) may play a growing role in HCC epidemiology. In this review, we sought to explore the relationship between liver steatosis and HCC.Methods: A narrative review was conducted using the PubMed MeSH search. The eligible papers were identified using a standard PubMed search with relevant key terms and various synonyms.Results: According to the results, patients with NAFLD-HCC tended to be older than those with hepatitis C virus (HCV)-HCC, and they were more often obese and had concomitant diseases, such as diabetes. On the other hand, the synthetic liver function was better preserved in NAFLD-HCC patients, who also obtained lower scores on the Model for End-stage Liver Disease (MELD) and Child-Turcotte-Pugh (CTP). However, it has to be noted that HCC in patients with non-alcoholic steatohepatitis (NASH) may develop without underlying cirrhosis. Although NASH-HCC is usually smaller and well-differentiated compared to HCV-HCC, the prognosis is similar in both groups. Efficient HCC screening in NASH cirrhosis poses a challenge because it is difficult to perform ultrasound examination in obese patients and alfa-fetoprotein level is no longer considered reliable.Conclusions: The constantly increasing prevalence of NAFLD in the general population can contribute to a growing role of NAFLD/NASH in HCC epidemiology. Moreover, some particular challenges specific for patients with liver steatosis may impede proper HCC diagnosis, treatment and follow-up.

Homeostatic Model Assessment of Insulin Resistance for Predicting the Recurrence of Hepatocellular Carcinoma after Curative Treatment

Diabetes mellitus (DM) is a risk factor for hepatocellular carcinoma (HCC). The purpose of this study was to investigate the impact of the disorder of glucose metabolism on the recurrence of HCC after curative treatment. Two hundred and eleven patients with HCC who received curative treatment in our hospital from 2006 to 2017 were enrolled in this study. Recurrence-free survival was estimated using the Kaplan–Meier method, and the differences between the groups partitioned by the presence or absence of DM and the values of hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), fasting immunoreactive insulin (FIRI), and homeostasis model assessment-insulin resistance (HOMA-IR) were evaluated using the log-rank test. There were no significant differences in the recurrence-free survival rate between the patients with and without DM (p = 0.144), higher and lower levels of HbA1c (≥6.5 and <6.5%, respectively; p = 0.509), FPG (≥126 and <126 mg/dL, respectively; p = 0.143), and FIRI (≥10 and <10 μU/mL, respectively; p = 0.248). However, the higher HOMA-IR group (≥2.3) had HCC recurrence significantly earlier than the lower HOMA-IR group (<2.3, p = 0.013). Moreover, there was a significant difference between the higher and lower HOMA-IR groups without DM (p = 0.009), and there was no significant difference between those groups with DM (p = 0.759). A higher HOMA-IR level, particularly in non-diabetic patients, was a significant predictor for HCC recurrence after curative treatment.

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.

Possible Mechanisms of Green Tea and Its Constituents against Cancer

A number of epidemiological, clinical, and experimental researches have indicated that administration of green tea appears to have anti-cancer activity. According to findings of laboratory cell culture studies, a diverse mechanism has been observed underlying the effects of green tea catechins against cancer. These mechanisms include anti-oxidant activity, cell cycle regulation, receptor tyrosine kinase pathway inhibition, immune system modulation, and epigenetic modification control. This review discusses the results of these studies to provide more insight into the effects of green tea administration on cancers observed to date in this research field.

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.

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.