Metabolic risk factors and primary liver cancer in a prospective study of 578,700 adults

Effects of PKM2 on global metabolic changes and prognosis in hepatocellular carcinoma: from gene expression to drug discovery

BACKGROUND

Hepatocellular carcinoma (HCC) is a malignant tumor that threatens global human health. High PKM2 expression is widely reported in multiple cancers, especially in HCC. This study aimed to explore the effects of PKM2 on global gene expression, metabolic damages, patient prognosis, and multiple transcriptional regulation relationships, as well as to identify several key metabolic genes and screen some small-molecule drugs.

METHODS

Transcriptome and clinical HCC data were downloaded from the NIH-GDC repository. Information regarding the metabolic genes and subsystems was collected from the Recon 2 human metabolic model. Drug-protein interaction data were obtained from the DrugBank and UniProt databases. We defined patients with PKM2 expression levels ≥11.25 as the high-PKM2 group, and those with low PKM2 expression (< 11.25) were defined as the low-PKM2 group.

RESULTS

The results showed that the global metabolic gene expression levels were obviously divided into the high- or low-PKM2 groups. In addition, a greater number of affected metabolic subsystems were observed in the high-PKM2 group. Furthermore, we identified 98 PKM2-correlated deregulated metabolic genes that were associated with poor overall patient survival. Together, these findings suggest more comprehensive influences of PKM2 on HCC. In addition, we screened several small-molecule drugs that target these metabolic enzymes, some of which have been used in antitumor clinical studies.

CONCLUSIONS

HCC patients with high PKM2 expression showed more severe metabolic damage, transcriptional regulation imbalance and poor prognosis than low-PKM2 individuals. We believe that our study provides valuable information for pathology research and drug development for HCC.

Metabolic syndrome and the incidence of hepatocellular carcinoma: a meta-analysis of cohort studies

Background

Patients with metabolic syndrome (MetS) were suggested to have a higher risk of hepatocellular carcinoma (HCC), although the results of previous cohort studies are not consistent.

Aim

To perform an updated meta-analysis to evaluate the association between MetS and subsequent incidence of HCC.

Methods

Relevant cohort studies were identified by searching PubMed and Embase databases. Cochrane's Q-test and I ² statistic were used to analyze the heterogeneity. Random effects model was used for the meta-analysis.

Results

Six cohort studies with 127,198 participants and 1,293 HCC cases during follow-up were included. Patients with MetS had a significantly higher incidence of HCC in studies with MetS defined by the revised National Cholesterol Education Program's Adults Treatment Panel III (risk ratio [RR]: 1.43, 95% CI: 1.19-1.72, p<0.001; I ²=29%) or International Diabetes Federation criteria (RR: 1.59, 95% CI: 1.13-2.23, p=0.008; I2=0%). Results of subgroup analysis showed that the presence of MetS was associated with a higher incidence of HCC in males (RR: 1.75, 95% CI: 1.28-2.38, p<0.001) but not in females (RR: 1.18, 95% CI: 0.76-1.84, p=0.46), and the association between MetS and higher risk of HCC was consistent regardless whether alcohol intake was adjusted. Although both were significant, MetS conferred higher risk of HCC in carriers of hepatitis B virus when compared with general population (p=0.06).

Conclusion

The presence of MetS is associated with significantly increased incidence of HCC in male participants.

Pooled Analysis of the Associations between Body Mass Index, Total Cholesterol, and Liver Cancer-related Mortality in Japan

Objective: We employed a large-scale pooled analysis to investigate the association of liver cancer-related mortality with being overweight/obese and total cholesterol (TC) levels, since limited and inconsistent data on these associations exist in Japan. Methods: A total of 59,332 participants (23,853 men and 35,479 women) from 12 cohorts without a history of cancer who were followed for a median of 14.3 years were analyzed. A sex-specific stratified Cox proportional hazards model adjusted for age and other potential confounders was used to calculate hazard ratios (HRs) and 95% confidence intervals (CI) for liver cancer-related mortality. Results: A total of 447 participants (266 men and 181 women) died of liver cancer within the follow-up period. Individuals classified as having a high BMI (≥25.0 kg/m2) and low TC levels (<160 mg/dL) had a significantly increased risk for liver cancer-related mortality (HR 7.05, 95% CI 4.41–11.26 in men; HR 8.07, 95% CI 4.76–13.67 in women) when compared with those in the intermediate BMI (18.5–24.9 kg/m2) and TC (160–219 mg/dL) categories. These associations remained after limiting the follow-up duration to >5 years. Conclusion: Being overweight/obese, combined with low TC levels, was strongly associated with liver cancer-related mortality in the EPOCH-JAPAN.

Obesity-associated miR-27a upregulation promotes hepatocellular carcinoma metastasis through suppressing SFRP1

Background

Obesity was a recognized risk factor for the development and progression of hepatocellular carcinoma (HCC). However, the effects and mechanisms by which obesity promotes HCC metastasis remain poorly understood.

Materials and methods

We cultured adipocyte induced by preadipocyte 3T3-L1 in vitro and established HCC metastasis model in obesity mouse in vivo to mimic the tumor microenvironment in obese status. The mechanisms underlying obesity-associated miR-27a upregulation promoting HCC metastasis were investigated.

Results

In this study, we showed that miR-27a was upregulated in adipocytes, obese mouse model and clinical samples, and the increased miR-27a level promoted migration and invasion in HCC cells, increased the number of metastasis nodes in obese mouse model, and was associated with poor clinical outcomes. Overexpressed secreted frizzled-related protein 1 in HCC cells and tissues significantly alleviated the upregulation of β-catenin and matrix metalloproteinase-7 induced by high level of miR-27a. Meanwhile, the E-cadherin expression decreased and Vimentin expression increased, linking with high level of β-catenin in high-fat group.

Conclusion

Taken together, our results have elucidated the critical role of extracellular miR-27a as a pro-metastatic factor in HCC and revealed that obesity-associated miR-27a upregulation promoted HCC metastasis through activated Wnt/β-catenin signaling by suppressing secreted frizzled-related protein 1. Our findings shed light on the novel mechanism underlying HCC metastasis and provided miR-27a as a promising target for obese liver cancer therapy.

Global Epidemiology, Prevention, and Management of Hepatocellular Carcinoma

The incidence rate of hepatocellular carcinoma (HCC) is rising. It is one of the most common cancers worldwide and accounts for substantial morbidity and mortality. Chronic hepatitis B virus (HBV) infection, chronic hepatitis C virus (HCV) infection, and nonalcoholic fatty liver disease (NAFLD) are the most important etiologies of HCC, and effective screening and management strategies are crucial to reduce the HCC risk. For HBV, which accounts for the majority of HCC cases, most infections were acquired via perinatal and early horizontal transmission. Universal vaccination of newborns has led to a decline in HCC incidence compared with the pre-vaccination era. Effective antiviral therapies with nucleos(t)ide analogues or pegylated interferon reduced the incidence of HCC. For HCV, the emergence of effective direct-acting antiviral (DAA) agents has substantially improved cure rates; therefore all patients with HCV should be considered for DAA treatment. The most important obstacle in eliminating HCV is access to therapy. For NAFLD, the global incidence is increasing rapidly, thus its impact on HCC incidence may be explosive. Progression to HCC in NAFLD happens particularly in those with nonalcoholic steatohepatitis (NASH) and exacerbated by metabolic syndrome, or PNPLA3 gene polymorphism. Lifestyle changes are imperative while drug therapy has yet to demonstrate substantive protective effects on HCC prevention. For management of HCC, early diagnosis via imaging surveillance among persons with HCC risk factors remains the most important strategy to identify early-stage disease appropriate for resection or transplantation.

Blood glucose concentration and risk of liver cancer: systematic review and meta-analysis of prospective studies

The question of whether elevated blood glucose is a risk factor for liver cancer has been intensively studied, yet with inconsistent results. To explore the relationship between blood glucose concentration and risk of liver cancer, we conduct a meta-analysis of prospective studies. Literature search was comprehensively performed using database of PubMed, EMBASE and the Cochrane Library through October 2016. Random-effect models were used to combine the effect estimations. Eight articles containing ten studies with a total of 1975 liver cancer cases were included. The pooled RRs demonstrated that elevated fasting blood glucose was associated with increased risk of liver cancer (combined RRs: 1.77; 95% CI: 1.46, 2.13) with mild heterogeneity (I2 = 30.40%, P = 0.17). In sensitivity analysis, the pooled result remained significant (combined RRs: 1.33; 95% CI: 1.12, 1.59; I2 = 33.90%, P = 0.16) when we restricted blood glucose categories in the range of nondiabetic subjects. We also detected a J-shaped non-linear dose-response relationship between blood glucose concentration and risk of liver cancer. There is evidence that elevated blood glucose increases risk of liver cancer across the range of prediabetes and diabetes. Considering the rapidly increasing prevalence of prediabetes and diabetes, controlling blood glucose may lower the risk of liver cancer.

Diabetes, metabolic comorbidities, and risk of hepatocellular carcinoma: Results from two prospective cohort studies

Type 2 diabetes (T2D) is a risk factor for hepatocellular carcinoma (HCC). However, it is unknown whether T2D duration or additional metabolic comorbidities further contribute to HCC risk. From the Nurses' Health Study (NHS), 120,826 women were enrolled in 1980, and from the Health Professionals Follow-up Study (HPFS), 50,284 men were enrolled in 1986 and followed through 2012. Physician-diagnosed T2D was ascertained at baseline and updated biennially. Cox proportional hazards regression models were used to calculate age- and multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident HCC. Over 32 years of follow-up (4,488,410 person-years), we documented 112 cases of HCC (69 women, 43 men). T2D was associated with an increased HCC risk (multivariable HR, 4.59; 95% CI, 2.98-7.07), as was an increasing T2D duration (P_trend  < 0.001). Compared to nondiabetics, the multivariable HRs for HCC were 2.96 (95% CI, 1.57-5.60) for 0-<2 years; 6.08 (95% CI, 2.96-12.50) for 2-<10 years; and 7.52 (95% CI, 3.88-14.58) for ≥10 years. Increasing number of metabolic comorbidities (T2D, obesity, hypertension, and dyslipidemia) was associated with increased HCC risk (P_trend  < 0.001); compared to individuals without metabolic comorbidity, those with four metabolic comorbidities had an 8.1-fold increased HCC risk (95% CI, 2.48-26.7). In T2D, neither insulin use nor oral hypoglycemic use was significantly associated with HCC risk (HR, 2.04 [95% CI, 0.69-6.09] and HR, 1.45 [95% CI, 0.69-3.07], respectively).

CONCLUSION

T2D is independently associated with increased risk for HCC in two prospective cohorts of U.S. men and women. This risk is enhanced with prolonged diabetes duration and with comorbid metabolic conditions, suggesting the importance of insulin resistance in the pathogenesis of HCC. (Hepatology 2018;67:1797-1806).

Epigenome-wide association study of metabolic syndrome in African-American adults

Background

The high prevalence of obesity among US adults has resulted in significant increases in associated metabolic disorders such as diabetes, dyslipidemia, and high blood pressure. Together, these disorders constitute metabolic syndrome, a clinically defined condition highly prevalent among African-Americans. Identifying epigenetic alterations associated with metabolic syndrome may provide additional information regarding etiology beyond current evidence from genome-wide association studies.

Methods

Data on metabolic syndrome and DNA methylation was assessed on 614 African-Americans from the Hypertension Genetic Epidemiology Network (HyperGEN) study. Metabolic syndrome was defined using the joint harmonized criteria, and DNA methylation was assessed using the Illumina HumanMethylation450K Bead Chip assay on DNA extracted from buffy coat. Linear mixed effects regression models were used to examine the association between CpG methylation at > 450,000 CpG sites and metabolic syndrome adjusted for study covariates. Replication using DNA from a separate sample of 69 African-Americans, as well as meta-analysis combining both cohorts, was conducted.

Results

Two differentially methylated CpG sites in the IGF2BP1 gene on chromosome 17 (cg06638433; p value = 3.10 × 10^− 7) and the ABCG1 gene on chromosome 21 (cg06500161; p value = 2.60 × 10^− 8) were identified. Results for the ABCG1 gene remained statistically significant in the replication dataset and meta-analysis.

Conclusion

Metabolic syndrome was consistently associated with increased methylation in the ABCG1 gene in the discovery and replication datasets, a gene that encodes a protein in the ATP-binding cassette transporter family and is involved in intra- and extra-cellular signaling and lipid transport.

Electronic supplementary material

The online version of this article (10.1186/s13148-018-0483-2) contains supplementary material, which is available to authorized users.

Genetic factors associated with risk of metabolic syndrome and hepatocellular carcinoma

Although the metabolic syndrome is a commonplace topic, its potential threats to public health is a problem that cannot be neglected. As the living conditions improved significantly over the past few years, the morbidity of metabolic syndrome has also steadily risen, and the onset age is becoming younger. The hepatocellular carcinoma (HCC), is one of the most prevalent life-threatening human cancers worldwide, incidence of which is also on the rise, gradually occupied the top of the list associated with metabolic syndrome related complication. Despite the advanced improvement of HCC management, the lifestyle, environmental factors, obesity, hepatitis B virus (HBV) infection have been recognized as risk factors for the development of liver cancer. In recent years, genetic studies, especially the genome-wide association studies (GWASs) were widely performed, a new era of the human genome research was created, which has significantly promoted the study of complex disease genetics. These progresses have contributed to the discovery of abundant number of genomic loci convincingly linked with complex metabolic feature and HCC. In this review, we briefly summarize the association between metabolic syndrome and HCC, focusing on the genetic factors contributed to metabolic syndrome and HCC.

Human Gut Microbiota and Gastrointestinal Cancer

Human gut microbiota play an essential role in both healthy and diseased states of humans. In the past decade, the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities, as well as the possible mechanisms through which the microbiota are involved in cancer prevention, carcinogenesis, and anti-cancer therapy. A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways. Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing inflammation and immune dysregulation, which lead to genetic instability, but also interfere with the pharmacodynamics of anticancer agents. In this article, we mainly reviewed the influence of gut microbiota on cancers in the gastrointestinal (GI) tract (including esophageal, gastric, colorectal, liver, and pancreatic cancers) and the regulation of microbiota by diet, prebiotics, probiotics, synbiotics, antibiotics, or the Traditional Chinese Medicine. We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future. We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers, which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, diagnosis, and treatment.

Human Gut Microbiota and Gastrointestinal Cancer

Human gut microbiota play an essential role in both healthy and diseased states of humans. In the past decade, the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities, as well as the possible mechanisms through which the microbiota are involved in cancer prevention, carcinogenesis, and anti-cancer therapy. A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways. Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing inflammation and immune dysregulation, which lead to genetic instability, but also interfere with the pharmacodynamics of anticancer agents. In this article, we mainly reviewed the influence of gut microbiota on cancers in the gastrointestinal (GI) tract (including esophageal, gastric, colorectal, liver, and pancreatic cancers) and the regulation of microbiota by diet, prebiotics, probiotics, synbiotics, antibiotics, or the Traditional Chinese Medicine. We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future. We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers, which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, diagnosis, and treatment.

Differential Response of B Cells to an Immunogen, a Mitogen and a Chemical Carcinogen in a Mouse Model System

Background: B cells are specific antibody generating cells which respond to foreign intruders in the circulation. The purpose of this study was to compare the relative immunogenic potentials of three well established agent types viz. an immunogen, a mitogen and a carcinogen, by following B cell responses to their presence in a mouse model system. Methods: Mice were treated with tetanus toxoid (immunogen), poke weed mitogen (typical mitogen), and benzo-α- pyrene (carcinogen) and generated B cell populations were determined in isolated splenic lymphocytes (splenocytes) by flow cytometry using specific anti-B cell marker antibodies. Flow cytometric estimation of LDL receptor (LDLR) expression, along with associated B cell markers, was also conducted. Kit based estimation of serum IgG, western blotting for LDLR estimation on total splenocytes and spectrometry for cholesterol and serum protein estimation were further undertaken. Student’s T-tests and one way ANOVA followed by the Bonferroni method were employed for statistical analysis. Results: The mitogen was found to better stimulate B cell marker expression than the immunogen, although the latter was more effective at inducing antibody production. The chemical carcinogen benzo-α-pyrene at low concentration acted potentially like a mitogen but almost zero immunity was apparent at a carcinogenic dose, with a low profile for LDLR expression and intracellular cholesterol. Conclusion: The findings in our study demonstrate an impact of concentration of BaP on generation of humoral immunity. Probably by immunosuppression through restriction of B-cell populations and associated antibodies, benzo-α-pyrene may exerts carcinogenicity. The level of cholesterol was found to be a pivotal target.

Facilitatory effect of insulin treatment on hepatocellular carcinoma development in diabetes

BACKGROUND

To evaluate the effect of insulin treatment on the incidence and/or severity of hepatocellular carcinoma (HCC) in a mouse model of HCC based on diabetes.

METHODS

We recently reported that neonatal streptozotocin (STZ) treatment causes type 1 diabetes and subsequent HCC in ddY, Institute for Animal Reproduction (DIAR) mice. Newborn male DIAR mice were divided into three groups based on STZ and insulin (INS) treatment. STZ was subcutaneously injected (60 mg/g) into the STZ-treated group (DIAR-nSTZ mice, N = 13) and the STZ/insulin-treated group (DIAR-nSTZ/INS mice, N = 20). A physiologic solution was injected into the control group (DIAR-control mice, N = 8) 1.5 days after birth. Insulin was subcutaneously injected into the DIAR-nSTZ/INS mice according to the following protocol: 2 IU/day at 4-5 weeks of age, 3 IU/day at 5-7 weeks of age, and 4 IU/day at 7-12 weeks of age. All mice were fed a normal diet and were subjected to physiological and histopathological assessments at 12 weeks of age.

RESULTS

DIAR-nSTZ mice had significantly lower body weight and higher blood glucose levels than DIAR-control mice, whereas no significant differences were observed between DIAR-nSTZ/INS mice and control mice. At 12 weeks of age, lower weight of paratesticular fat and higher levels of total cholesterol, triglyceride, and free fatty acids were observed in DIAR-nSTZ mice compared to DIAR-control mice, whereas there were no significant differences between DIAR-nSTZ/INS mice and DIAR-control mice. In the livers of DIAR-nSTZ mice, HCC was observed in 15% of cases, and dysplastic nodules were observed in 77% of cases. In the livers of DIAR-nSTZ/INS mice, HCC was observed in 39% of cases and dysplastic nodules were observed in 61% of cases (p = 0.011). Moreover, the average tumor size was significantly larger in STZ/INS-treated mice than in STZ-treated mice. Immunohistochemical analysis demonstrated that the expression of ERK1/2, downstream substrates of insulin signaling that activate cell proliferation, was significantly higher in STZ/INS-treated mice compared to STZ-treated mice.

CONCLUSIONS

Insulin treatment promoted, rather than inhibited, the progression of liver carcinogenesis in DIAR-nSTZ mice. Hyperinsulinemia rather than hyperglycemia can accelerate the progression of HCC via insulin signaling.

The association between fasting blood glucose and the risk of primary liver cancer in Chinese males: a population-based prospective study

BACKGROUND

To investigate the association between fasting blood glucose (FBG) levels and the risk of incident primary liver cancer (PLC) in Chinese males, a large prospective cohort was performed in the current study.

METHODS

A total of 109 169 males participating in the routine checkups every two years were recruited in the Kailuan male cohort study since May 2006. Cox proportional hazards regression models and restricted cubic spline (RCS) were used to evaluate the association between levels of baseline FBG and the risk of incident PLC.

RESULTS

Compared to the males with normal FBG (3.9⩽FBG<6.1 mmol l^-1), the males with impaired fasting glucose (IFG: 6.1⩽FBG<7.0 mmol l^-1) and diabetes mellitus (DM: FBG ⩾7.0 mmol l^-1) had a 60% (95% CI: 1.09-2.35) and a 58% (95% CI: 1.07-2.34) higher risk of incident PLC, respectively. Subgroup analysis found that IFG increased the risk of PLC among the non-smoker (HR=1.73, 95% CI: 1.01-2.98) and current alcohol drinker (HR=1.80, 95% CI: 1.03-3.16). While DM increased the risk of PLC especially among the males with normal BMI (<25 kg m^-2) (HR=1.76, 95% CI: 1.05-2.94) and the HBV negativity (HR=1.89, 95% CI: 1.16-3.09), RCS analysis showed a positive non-linearly association between the FBG levels and the risk of PLC (p-overall=0.041, p-non-linear=0.049).

CONCLUSIONS

Increased FBG may be an important and potentially modifiable exposure that could have key scientific and clinical importance for preventing PLC development.

Cardio-oncology Related to Heart Failure: Common Risk Factors Between Cancer and Cardiovascular Disease

There is a growing body of evidence that suggests cancer and cardiovascular disease have a shared biological mechanism. Although there are several shared risk factors for both diseases, including advancing age, gender, obesity, diabetes, physical activity, tobacco use, and diet, inflammation and biomarkers, such as insulinlike growth factor 1, leptin, estrogen, and adiponectin, may also play a role in the biology of these diseases. This article provides an overview of the shared biological mechanism between cancer and cardiovascular disease.

The association between individual metabolic syndrome components, primary liver cancer and cirrhosis: A study in the Swedish AMORIS cohort

Metabolic syndrome (MetS) is associated with non-alcoholic fatty liver disease, which may progress to cirrhosis, a significant risk factor of hepatocellular carcinoma (HCC), the commonest malignant primary liver cancer (PLC). We investigated the association between the individual components of MetS (lipids, apolipoproteins, raised glucose, diabetes and obesity), PLC and cirrhosis. A total of 509,436 participants from the Swedish AMORIS cohort, recruited between January 1985 and December 1996 (end-date December 2011), aged ≥20 with baseline triglycerides (TG), total cholesterol (TC), glucose and liver enzymes were included. Those with baseline benign liver tumours, PLC or cirrhosis were excluded. Multivariate Cox regression, adjusted for age, gender, socio-economic status, liver disease (excluding cirrhosis) and MetS factors were used to estimate the association with PLC and cirrhosis. There were 766 PLC and 2,775 cirrhosis cases over 13 years. Raised TG, low TC, raised glucose, diabetes and low HDL were associated with an increased risk of developing PLC and cirrhosis. ApoB/ApoA-I ratio were also associated with PLC, whilst low LDL, raised TG/HDL, low ApoA-I and low ApoB were associated with cirrhosis. Obesity was significantly associated with PLC but not cirrhosis. Raised TG, low TC, raised glucose and diabetes showed stronger associations with PLC in participants with cirrhosis but many participants developed PLC without cirrhosis. Individual components of MetS (lipids, apolipoproteins, raised glucose, diabetes and obesity) were associated with an increased risk of developing PLC or cirrhosis. MetS components were more strongly associated with PLC with preceding cirrhosis history but many participants developed PLC without cirrhosis.

Obesity and Liver Cancer

Obesity and related metabolic disorders have become globally prevalent posing a challenge for the chronically damaged liver and predisposing the development and progression of cancer. The rising phenomenon of "obesity epidemic" may provide means for understanding why liver cancer is one of the few malignancies with rising incidence in developed countries over the last decades. Non-alcoholic fatty liver disease associated with obesity, insulin resistance, and type 2 diabetes is an increasingly recognized trigger for liver cancer in Western populations characterized by low prevalence of established risk factors for liver cancer such as viral hepatitis and hepatotoxin exposure. Accumulating evidence has established an association between higher body mass index as an indicator of general obesity and higher risk of primary liver cancer. The associations are stronger in men, in patients with underlying liver disease and in white ethnic groups. Abdominal obesity, weight gain in adult life and metabolic factors related to visceral fat accumulation were also suggested as important risk factors for liver cancer; however, more studies are needed to evaluate these associations. The association of obesity and metabolic parameters with liver cancer survival remains controversial. It is unclear which exact mechanisms could provide links between obesity and liver cancer risk. Recent evidence has implicated several molecular pathways in obesity-associated liver cancer. These include insulin resistance leading to increased levels of insulin and insulin-like growth factors, chronic inflammation, adipose tissue remodeling, pro-inflammatory cytokine and adipokine secretion, and altered gut microbiota. These mechanisms coincide with inflammatory and metabolic processes occurring in non-alcoholic fatty liver disease predisposing cancer development and progression. In the context of the current evidence, better understanding of the role of obesity and related metabolic factors may help in improving current strategies for liver cancer prevention.

Independent of Cirrhosis, Hepatocellular Carcinoma Risk Is Increased with Diabetes and Metabolic Syndrome

BACKGROUND

Hepatocellular carcinoma is the most common primary liver malignancy, commonly a sequelae of hepatitis C infection, but can complicate cirrhosis of any cause. Whether metabolic syndrome and its components, type II diabetes, hypertension, and hyperlipidemia increase the risk of hepatocellular carcinoma independent of cirrhosis is unknown.

METHODS

A retrospective cohort study was conducted using the MarketScan insurance claims database from 2008-2012. Individuals with hepatocellular carcinoma aged 19-64 years and age and sex-matched controls were included. Multivariate analysis of hepatocellular carcinoma risk factors was performed.

RESULTS

Hepatitis C (odds ratio [OR] 2.102) was the largest risk factor for hepatocellular carcinoma. Other independent risk factors were type II diabetes (OR 1.353) and hypertension (OR 1.229). Hyperlipidemia was protective against hepatocellular carcinoma (OR 0.885). The largest risk increase occurred with hypertension with type II diabetes and hepatitis C (OR 4.580), although hypertension and type II diabetes without hepatitis C still incurred additional risk (OR 3.399). Type II diabetes and hyperlipidemia had a similar risk if hepatitis C was present (OR 2.319) or not (OR 2.395). Metformin (OR 0.706) and cholesterol medications (OR 0.645) were protective in diabetics. Insulin (OR 1.640) increased the risk of hepatocellular carcinoma compared with the general type II diabetes population.

CONCLUSION

In the absence of cirrhosis, type II diabetes and hypertension were independent risk factors for hepatocellular carcinoma. Hyperlipidemia and medical management of type II diabetes with metformin and cholesterol medication appeared to reduce the incidence of hepatocellular carcinoma. In contrast, insulin was associated with a higher risk of hepatocellular carcinoma.

Association of Metabolic Syndrome and Human Papillomavirus Infection in Men and Women Residing in the United States

Background: An estimated 33% of adults in the United States have metabolic syndrome (MetS), which has been associated with an increased risk for various cancer types. Theories of synergism among components of MetS that increase cancer risk via chronic inflammation and oxidative stress have been proposed. We hypothesize that men and women with MetS may have compromised immunological response resulting in increased risk for persistent human papillomavirus (HPV) infection. The goal of this study is to determine the association of MetS with HPV types 6, 11, 16, and 18 and to explore variation of these associations by gender using data from a national survey.Methods: We conducted a retrospective cross-sectional study using data from the National Health and Nutrition Examination Survey.Results: Thirty-two percent of the population sampled met the criteria for MetS (16% men and 33% women). Nineteen percent tested positive for HPV (6, 11, 16, and 18). Prevalence of HPV infection was estimated at 13% for men and 30% for females. MetS was found to be significantly associated with increased risk of HPV6, 11, 16, or 18 in the entire cohort [RR = 1.24; 95% confidence interval (CI), 1.03-1.48] and in females (RR = 1.26; 95% CI, 1.02-1.56). Although the adjusted risk of HPV+ve status was found to be 21% higher in men with MetS compared with those without, this difference did not attain statistical significance.Conclusions: We observed a significant association between metabolic syndrome and HPV sero-positivity among the overall population and among females. Although not significant, a similar effect was noted in men. Further prospective studies are needed to better understand this relationship.Impact: To the best of our knowledge, this is the first study evaluating the impact of metabolic syndrome on HPV positivity in both males and females. Cancer Epidemiol Biomarkers Prev; 26(8); 1321-7. ©2017 AACR.

Metabolic Syndrome Prevalence by Race/Ethnicity and Sex in the United States, National Health and Nutrition Examination Survey, 1988-2012

Introduction

Metabolic syndrome is a cluster of cardiometabolic risk factors associated with increased risk of multiple chronic diseases, including cancer and cardiovascular disease. The objectives of this study were to estimate the prevalence of metabolic syndrome overall, by race and sex, and to assess trends in prevalence from 1988 through 2012.

Methods

We analyzed data from the National Health and Nutrition Examination Survey (NHANES) for 1988 through 2012. We defined metabolic syndrome as the presence of at least 3 of these components: elevated waist circumference, elevated triglycerides, reduced high-density lipoprotein cholesterol, high blood pressure, and elevated fasting blood glucose. Data were analyzed for 3 periods: 1988–1994, 1999–2006, and 2007–2012.

Results

Among US adults aged 18 years or older, the prevalence of metabolic syndrome rose by more than 35% from 1988–1994 to 2007–2012, increasing from 25.3% to 34.2%. During 2007–2012, non-Hispanic black men were less likely than non-Hispanic white men to have metabolic syndrome (odds ratio [OR], 0.77; 95% confidence interval [CI], 0.66–0.89). However, non-Hispanic black women were more likely than non-Hispanic white women to have metabolic syndrome (OR, 1.20; 95% CI, 1.02–1.40). Low education level (OR, 1.56; 95% CI, 1.32–1.84) and advanced age (OR, 1.73; 95% CI, 1.67–1.80) were independently associated with increased likelihood of metabolic syndrome during 2007–2012.

Conclusion

Metabolic syndrome prevalence increased from 1988 to 2012 for every sociodemographic group; by 2012, more than a third of all US adults met the definition and criteria for metabolic syndrome agreed to jointly by several international organizations.

Characteristics of patients with liver cancer in the BioBank Japan project

Background

Liver cancer is the fifth cause of cancer-related deaths in Japan. The BioBank Japan (BBJ) project included 200,000 patients with 47 diseases and samples; their clinical information can be used for further studies.

Methods

Patients diagnosed with liver cancer (n = 1733; 1316 men, 417 women) were included. Histology, patient characteristics, clinical characteristics, and causes of death were collected. Cumulative and relative survival rates for liver cancer were calculated.

Results

Of the 1354 patients with available liver cancer histology, 91.9% had hepatocellular carcinoma (HCC). Compared with the National Health and Nutrition Examination Survey, greater proportions of the male patients in this cohort were daily alcohol consumers (26%), and a greater proportion of the men was overweight/obesity (22%). Although Japan is the only Asian country with a predominance of hepatitis C virus (HCV)-related HCC, the prevalence of HCV infection (44%) was lower than that in a previous study. The 3-, 5-, and 10-year cumulative survival rates were 57%, 47%, and 25% in men, respectively, and 49%, 41%, and 27% in women, respectively.

Conclusions

The present results provide an overview of the patients with liver cancer in the BBJ project. We are planning further analyses combined with various high-throughput ‘omics’ technologies.

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Liver cancer is the second leading cause of death worldwide.

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We aimed to provide an overview of patients with liver cancer.

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Based on liver cancer histology, 91.9% had hepatocellular carcinoma.

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The 10-year relative survival rates were 34% in men and 38% in women.

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Future studies will help develop preventive programs for liver cancer.

Analysis of Preoperative Metabolic Risk Factors Affecting the Prognosis of Patients with Esophageal Squamous Cell Carcinoma: The Fujian Prospective Investigation of Cancer (FIESTA) Study

Some metabolic factors have been shown to be associated with an increased risk of esophageal cancer; however the association with its prognosis is rarely reported. Here, we assessed the prediction of preoperative metabolic syndrome and its single components for esophageal cancer mortality by analyzing a subset of data from the ongoing Fujian prospective investigation of cancer (FIESTA) study. Between 2000 and 2010, patients who underwent three-field lymphadenectomy were eligible for inclusion. Blood/tissue specimens, demographic and clinicopathologic data were collected at baseline. Metabolic syndrome is defined by the criteria proposed by Chinese Diabetes Society. In this study, analysis was restricted to esophageal squamous cell carcinoma (ESCC) due to the limited number of other histological types. The median follow-up in 2396 ESCC patients (males/females: 1822/574) was 38.2months (range, 0.5-180months). The multivariate-adjusted hazard ratio (HR) of metabolic syndrome for ESCC mortality was statistically significant in males (HR, 95% confidence interval, P: 1.45, 1.14-1.83, 0.002), but not in females (1.46, 0.92-2.31, 0.107). For single metabolic components, the multivariate-adjusted HRs were significant for hyperglycemia (1.98, 1.68-2.33, <0.001) and dyslipidemia (1.41, 1.20-1.65, <0.001) in males and for hyperglycemia (1.76, 1.23-2.51, <0.001) in females, independent of clinicopathologic characteristics and obesity. In tree-structured survival analysis, the top splitting factor in both genders was tumor-node-metastasis stage, followed by regional lymph node metastasis. Taken together, our findings demonstrate that preoperative metabolic syndrome was a significant independent predictor of ESCC mortality in males, and this effect was largely mediated by glyeolipid metabolism disorder.

APSA Awardee Submission: Tumor/cancer stem cell marker doublecortin-like kinase 1 in liver diseases

Liver diseases are the fourth leading cause of mortality among adults in the United States. Patients with chronic liver diseases such as viral hepatitis, fibrosis, and cirrhosis have significantly higher risks of developing hepatocellular carcinoma (HCC). With a dismal five-year survival rate of 11%, HCC is the third most common cause of cancer-related deaths worldwide. Regardless of the underlying cause, late presentation and a lack of effective therapy are the major impediments for successful treatment of HCC. Therefore, there is a considerable interest in developing new strategies for the prevention and treatment of chronic liver diseases at the early stages. Cancer stem cells (CSCs), a small cell subpopulation in a tumor, exhibit unlimited self-renewal and differentiation capacity. These cells are believed to play pivotal roles in the initiation, growth, metastasis, and drug-resistance of tumors. In this review, we will briefly discuss pivotal roles of the CSC marker doublecortin-like kinase 1 (DCLK1) in hepatic tumorigenesis. Recent evidence suggests that anti-DCLK1 strategies hold promising clinical potential for the treatment of cancers of the liver, pancreas, and colon.

Impact of metabolic syndrome on the survival of Chinese patients with resectable esophageal squamous cell carcinoma

Metabolic syndrome (MetS) is associated with the risk of esophageal squamous cell carcinoma (ESCC). However, the impact of MetS on survival has not been evaluated. A retrospective review was performed on 596 consecutive Chinese patients with esophageal squamous cell carcinoma who received surgery between January 2005 and October 2007. The clinical data and pretreatment information related to MetS were reviewed. The impact of MetS on overall survival (OS) was estimated by Kaplan-Meier and Cox proportional hazards analyses. MetS was a significant and independent predictor for better survival in patients with resectable ESCC. The 3-year OS and 5-year OS for patients with and without MetS were 75.0% versus 57.8% and 65.1% versus 44.6%, respectively (P = 0.005 in the univariate analysis, P = 0.010 in multivariate analysis). However, there was no apparent influence of any single component of MetS on OS. The other independent prognostic factors identified in the univariate analysis included the following: gender, smoking status, alcohol use, the extent of radical surgical resection, T and N stage, and tumor differentiation. The results of the multivariate analysis included the extent of radical surgery resection, T and N stage, and tumor differentiation. MetS was also associated with greater tumor cell differentiation (P = 0.036). There was no association found between MetS status and postoperative complications. MetS is an independent prognostic factor for OS in patients with ESCC and is associated with better tumor cell differentiation.

Mitochondria, cholesterol and cancer cell metabolism

Given the role of mitochondria in oxygen consumption, metabolism and cell death regulation, alterations in mitochondrial function or dysregulation of cell death pathways contribute to the genesis and progression of cancer. Cancer cells exhibit an array of metabolic transformations induced by mutations leading to gain-of-function of oncogenes and loss-of-function of tumor suppressor genes that include increased glucose consumption, reduced mitochondrial respiration, increased reactive oxygen species generation and cell death resistance, all of which ensure cancer progression. Cholesterol metabolism is disturbed in cancer cells and supports uncontrolled cell growth. In particular, the accumulation of cholesterol in mitochondria emerges as a molecular component that orchestrates some of these metabolic alterations in cancer cells by impairing mitochondrial function. As a consequence, mitochondrial cholesterol loading in cancer cells may contribute, in part, to the Warburg effect stimulating aerobic glycolysis to meet the energetic demand of proliferating cells, while protecting cancer cells against mitochondrial apoptosis due to changes in mitochondrial membrane dynamics. Further understanding the complexity in the metabolic alterations of cancer cells, mediated largely through alterations in mitochondrial function, may pave the way to identify more efficient strategies for cancer treatment involving the use of small molecules targeting mitochondria, cholesterol homeostasis/trafficking and specific metabolic pathways.

Statins and Reduced Risk of Liver Cancer: Evidence for Confounding

A negative association of statin use with liver cancer risk has been reported frequently. We added laboratory measurements, to our knowledge not included in previous investigations, to a case-control analysis of 2877 case patients and 142 850 matched control subjects enrolled in Kaiser Permanente Northern California. Addressing confounding by indication by restricting subjects to those with elevated cholesterol greatly attenuated the negative association; eg, the multivariable-adjusted odds ratio (OR) rose from 0.41 (95% confidence interval [CI] = 0.35 to 0.49) to 0.87 (95% CI = 0.55 to 1.39) for receipt of 18 or more prescriptions. Confounding by contraindication was addressed by controlling for degree of abnormality of liver function tests, alanine or aspartate transaminase, measured within one year of the elevated cholesterol and strongly related to risk. The negative association of statins disappeared for all numbers of prescriptions received, with an odds ratio of 1.21 (95% CI = 0.53 to 2.75) for 18 or more prescriptions. Findings cast doubt on the causality of the frequently observed preventive association.

Obesity, diabetes, serum glucose, and risk of primary liver cancer by birth cohort, race/ethnicity, and sex: Multiphasic health checkup study

OBJECTIVE

Obesity and diabetes have been associated with liver cancer. However, recent US-based studies have suggested a lack of association between obesity and liver cancer among blacks and women.

METHODS

We conducted a nested case-control study within the Multiphasic Health Checkup (MHC) cohort of Kaiser Permanente Northern California (KPNC) members. Liver cancer was diagnosed using the KPNC Cancer Registry. Detailed self-administered questionnaires and a standardized examination that included measurement of height and weight and a 1-h glucose tolerance test were completed prior to diagnosis of liver cancer for cases (n=450) and matched controls (4489). Height and weight were utilized to calculate BMI (kg/m(2)) as a measure of adiposity: underweight (15-≤8.5kg/m(2)), normal weight (18.5-≤25kg/m(2)), overweight (25-≤30kg/m(2)), and obese (≥30kg/m(2)). Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) for the association between BMI, diabetes, and serum glucose with subsequent incidence of liver cancer, in models that were stratified by birth cohort, race/ethnicity, and sex.

RESULTS

Compared to normal weight individuals, obese individuals had a 2.4-fold increased risk of liver cancer (OR=2.38, 95% CI: 1.68-3.36), and overweight individuals had a 32% increased risk (OR=1.32, 95% CI: 1.03-1.70). This association did not differ when stratified by birth cohort, race/ethnicity, or sex (pint>0.05). Among blacks and women, obesity was associated with at least a 2-fold increased risk of liver cancer (OR=2.29, 95% CI: 1.22-4.28 and OR=2.00, 95% CI: 1.14-3.52, respectively). More moderate increased odds ratios were noted for diabetes (OR=1.28, 95% CI: 0.65-2.54) and serum glucose ≥200mg/dL (OR=1.63, 95% CI: 0.48-5.55), although the results did not attain statistical significance.

CONCLUSION

In summary, our finding of a positive association between obesity and liver cancer suggests that a higher BMI may increase the risk of liver cancer in the US, for both sexes and all race/ethnicities.

Oncogenic mutations and dysregulated pathways in obesity-associated hepatocellular carcinoma

Epidemiological studies showed that obesity and its related non-alcoholic fatty liver disease (NAFLD) promote hepatocellular carcinoma (HCC) development. We aimed to uncover the genetic alterations of NAFLD-HCC using whole-exome sequencing. We compared HCC development in genetically obese mice and dietary obese mice with wild-type lean mice fed a normal chow after treatment with diethylnitrosamine. HCC tumor and adjacent normal samples from obese and lean mice were then subjected to whole-exome sequencing. Functional and mechanistic importance of the identified mutations in Carboxyl ester lipase (Cel) gene and Harvey rat sarcoma virus oncogene 1 (Hras) was further elucidated. We demonstrated significantly higher incidences of HCC in both genetic and dietary obese mice with NAFLD development as compared with lean mice without NAFLD. The mutational signatures of NAFLD-HCC and lean HCC were distinct, with <3% overlapped. Eight metabolic or oncogenic pathways were found to be significantly enriched by mutated genes in NAFLD-HCC, but only two of these pathways were dysregulated by mutations in lean HCC. In particular, Cel was mutated significantly more frequently in NAFLD-HCC than in lean HCC. The multiple-site mutations in Cel are loss-of-function mutations, with effects similar to Cel knock-down. Mutant Cel caused accumulation of cholesteryl ester in liver cells, which led to induction of endoplasmic reticulum stress and consequently activated the IRE1α/c-Jun N-terminal kinase (JNK)/c-Jun/activating protein-1 (AP-1) signaling cascade to promote liver cell growth. In addition, single-site mutations in Hras at codon 61 were found in NAFLD-HCC but none in lean HCC. The gain-of-function mutations in Hras (Q61R and Q61K) significantly promoted liver cell growth through activating the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/3-phosphoinositide-dependent protein kinase-1 (PDK1)/Akt pathways. In conclusion, we have identified mutation signature and pathways in NAFLD-associated HCC. Mutations in Cel and Hras have important roles in NAFLD-associated hepatocellular carcinogenesis.

Prohibitin-induced, obesity-associated insulin resistance and accompanying low-grade inflammation causes NASH and HCC

Obesity increases the risk for nonalcoholic steatohepatitis (NASH) and hepatocarcinogenesis. However, the underlying mechanisms involved in the disease process remain unclear. Recently, we have developed a transgenic obese mouse model (Mito-Ob) by prohibitin mediated mitochondrial remodeling in adipocytes. The Mito-Ob mice develop obesity in a sex-neutral manner, but obesity-associated adipose inflammation and metabolic dysregulation in a male sex-specific manner. Here we report that with aging, the male Mito-Ob mice spontaneously develop obesity-linked NASH and hepatocellular carcinoma (HCC). In contrast, the female Mito-Ob mice maintained normal glucose and insulin levels and did not develop NASH and HCC. The anti-inflammatory peptide ghrelin was significantly upregulated in the female mice and down regulated in the male mice compared with respective control mice. In addition, a reduction in the markers of mitochondrial content and function was found in the liver of male Mito-Ob mice with NASH/HCC development. We found that ERK1/2 signaling was significantly upregulated whereas STAT3 signaling was significantly down regulated in the tumors from Mito-Ob mice. These data provide a proof-of-concept that the metabolic and inflammatory status of the adipose tissue and their interplay at the systemic and hepatic level play a central role in the pathogenesis of obesity-linked NASH and HCC.

The story of HCC in NAFLD: from epidemiology, across pathogenesis, to prevention and treatment

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide. An increasing number of reports describe HCC in the setting of obesity and diabetes, two major risk factors for non-alcoholic fatty liver disease (NAFLD). The increasing incidence of these conditions and the emerging evidence of HCC in non-cirrhotic NAFLD prioritize a better understanding of NAFLD-related HCC epidemiology and pathogenesis in order to target screening policies and develop preventive-therapeutic strategies. In this review, we focus on the epidemiological impact of this condition, suggesting a possible link between HCC in cryptogenic cirrhosis and NAFLD. Furthermore, we analyse the suggested pathogenic mechanisms and the possible preventive-therapeutic strategies.

Residual risk of hepatocellular carcinoma after HCV eradication: more than meets the eye

Eradication of HCV in patients with advanced liver fibrosis or cirrhosis reduces, but does not altogether abolish, the risk of development of hepatocellular carcinoma. The reasons underlying this residual risk remain elusive. Even if HCV clearance eliminates its direct and indirect carcinogenic effects, the persistence of cirrhosis and the possible coexistence of metabolic factors (diabetes, obesity and insulin resistance) and of alcohol abuse can promote the development of hepatocellular carcinoma acting as autonomous, nonviral carcinogenic factors. Lessons learned in the IFN era may still assist in predicting the forthcoming scenario, when IFN-free regimens will obtain high rates of viral clearance even at the most advanced stages of liver disease.

Diabetes and cancer, common threads and missing links

Diabetes mellitus is a serious and growing health problem worldwide and is associated with severe acute and chronic complications. Accruing epidemiological and clinical evidence have suggested that an increased cancer incidence is associated with diabetes as well as certain diabetes risk factors and diabetes medications. Several pathophysiological mechanisms for this relationship have been postulated, including insulin resistance and hyperinsulinemia, enhanced inflammation, aberrant metabolic state, endoplasmic reticulum stress, and deregulation of autophagy. In addition to these potential mechanisms, a number of common risk factors, including obesity, may be behind the association between diabetes and cancer. Furthermore, different anti-diabetic medications may modify cancer risk and mortality in patients with diabetes. This Review discusses evidence to support the relationship between diabetes and cancer development as well as the underlying mechanisms. We also discuss the relationship of current diabetes treatments and cancer risk or prognosis. Understanding the mechanisms that connect type 2 diabetes or diabetes treatments to cancer are crucial for establishing the fundamental strategies concerning about primary prevention, early detection and effective therapy against these diseases.

Cancer among patients with type 2 diabetes mellitus: A population-based cohort study in northeastern Italy

Diabetes mellitus (DM) is associated with an elevated risk of cancer. The aim of this study was to assess cancer risk and survival in individuals with type 2 DM (T2DM) in Friuli Venezia Giulia, Italy. A retrospective population-based cohort study of 32,247 T2DM patients aged 40-84 years was conducted through a record linkage of local healthcare databases and cancer registry for the period 2002-2009. Standardized incidence ratios (SIRs) with 95% confidence intervals (95%CIs) and 5-year survival probabilities after T2DM and cancer diagnosis were computed. The SIRs for all cancers (n=2069) was 1.28 (95%CI: 1.23-1.34). The highest SIRs were observed for cancers of the liver, female genital organs, small intestine, and pancreas. After 3 years from T2DM diagnosis, a reduced risk of prostate cancer (SIR=0.73, 95%CI: 0.54-0.96) was found in men aged 65-74 years, and a higher risk for breast cancer (SIR=1.24, 95%CI: 1.00-1.52) was found among T2DM female patients. The overall 5-year survival after T2DM was 88.7%. Furthermore, T2DM appeared to have a negative effect on survival of women with breast cancer. This population-based study confirmed that T2DM patients are at increased risk of several cancers, and of premature death in women with breast cancer.

Nutrition and Hepatocellular Cancer

BACKGROUND

Hepatocellular carcinoma (HCC) significantly contributes to the global burden of cancer. Liver cancer is the third most frequent cause of cancer-related death with HCC representing more than 90% of primary liver cancers. The majority of patients are not only affected by the malignant disease but do also suffer from chronic liver disease. Therefore, several factors impact on the prognosis of patients with HCC, including tumor-related factors, liver function and patient-related factors such as performance status and other comorbidities. The nutritional status is of high significance for the patients' performance status, the tolerance of tumor-targeting therapy and the prognosis of cancer of any type and is specially referenced in HCC. This overview is on current concepts on the role of nutritional factors in hepatocarcinogenesis and the role of nutrition in patients affected by HCC.

SUMMARY

Nutritional status and composition of diet are relevant factors related to the risk of HCC. They also have an important role concerning the prognosis of patients with HCC. Besides risk factors, several macro- and micronutrient components have been found to be inversely correlated with the risk of HCC. To prevent disease progression to liver cirrhosis or HCC in patients with nonalcoholic steatohepatitis, it is crucial to optimize the metabolic state.

KEY MESSAGE AND PRACTICAL IMPLICATION

Evidence from well-designed prospective interventional trials with the aim to reduce the HCC incidence or to prolong survival in patients with HCC based on nutritional modification is still to be generated.

Overexpression of Klotho suppresses liver cancer progression and induces cell apoptosis by negatively regulating wnt/β-catenin signaling pathway

Background

Klotho is a discovered aging suppressor gene, and its overexpression in mice extends the life span of the animal. Recently, Klotho is also identified as a tumor suppressor gene in variety of tumors; however, the potential role and the antitumor mechanism remain unclarified in liver cancers.

Methods

RT-PCR and western blotting analysis were used to detect the expression of Klotho, β-catenin, C-myc, and Cyclin D1. MTT assay was used to detect the survival rates of HepG2 and SMMC-7721 cells. Colony formation assay was used to test the proliferation ability in Klotho transfected cells. FACS was used to detect the cell apoptosis rate in different groups.

Results

The results showed that lower expression of Klotho were found in liver cancer cell lines than the immortalized liver cell L02. Also, MTT assay results found that overexpression or recombinant Klotho administration suppressed the proliferation of liver cancer cells HepG2 and SMMC-7721. Moreover, the colony formation assay results showed that the number of colonies was significantly lower in the cells with transfection with pCMV-Klotho than the controls. Thus, functional analysis demonstrated that Klotho expression inhibited the proliferation of liver cancer cells and Klotho worked as an important antitumor gene in tumor progression. Next, the mechanism was partly clarified that Klotho expression induced cell apoptosis in HepG2 and SMMC-7721 cells, and this phenomenon was mainly involved in the Wnt/β-catenin signaling pathway. The western blotting analysis revealed that overexpression or recombinant administration of Klotho obviously decreased the expression levels of β-catenin, C-myc, and Cyclin D1 in HepG2 cells. Most importantly, the antitumor mechanism for Klotho due to that overexpression of Klotho not only decreased the endogenous β-catenin levels but also inhibited the nuclear translocation of β-catenin to delay the cell cycle progression.

Conclusions

Klotho was a tumor suppressor gene, and overexpression of Klotho suppressed the proliferation of liver cancer cells partly due to negative regulation of Wnt/β-catenin signaling pathway. So, Klotho might be used as a potential target, and the study will contribute to treatment for therapy of liver cancer patients.

Liver Cancer: Connections with Obesity, Fatty Liver, and Cirrhosis

The burden of hepatocellular carcinoma (HCC), the most common form of liver cancer, is steadily growing because obesity, type 2 diabetes, and nonalcoholic fatty liver disease (NAFLD) are replacing viral- and alcohol-related liver disease as major pathogenic promoters. The most worrisome aspects of these new risk factors are their large spread in the general population and their link with HCC arising in noncirrhotic livers. HCC may be the presenting feature of an asymptomatic nonalcoholic steatohepatitis (NASH), the progressive form of NAFLD. The HCC risk connected to metabolic factors has been underestimated so far, and a poorer surveillance has prevented an adequate treatment. Systemic and hepatic molecular mechanisms involved in obesity- and NAFLD-induced hepatocarcinogenesis as well as potential early markers of HCC are being extensively investigated. This review summarizes current evidence linking obesity, NAFLD and liver cancer, discusses its clinical impact and describes the main mechanisms underlying this complex relationship.

Hepatocellular carcinoma: From clinical practice to evidence-based treatment protocols

Hepatocellular carcinoma (HCC) is one of the major malignant diseases in many healthcare systems. The growing number of new cases diagnosed each year is nearly equal to the number of deaths from this cancer. Worldwide, HCC is a leading cause of cancer-related deaths, as it is the fifth most common cancer and the third most important cause of cancer related death in men. Among various risk factors the two are prevailing: viral hepatitis, namely chronic hepatitis C virus is a well-established risk factor contributing to the rising incidence of HCC. The epidemic of obesity and the metabolic syndrome, not only in the United States but also in Asia, tend to become the leading cause of the long-term rise in the HCC incidence. Today, the diagnosis of HCC is established within the national surveillance programs in developed countries while the diagnosis of symptomatic, advanced stage disease still remains the characteristic of underdeveloped countries. Although many different staging systems have been developed and evaluated the Barcelona-Clinic Liver Cancer staging system has emerged as the most useful to guide HCC treatment. Treatment allocation should be decided by a multidisciplinary board involving hepatologists, pathologists, radiologists, liver surgeons and oncologists guided by personalized -based medicine. This approach is important not only to balance between different oncologic treatments strategies but also due to the complexity of the disease (chronic liver disease and the cancer) and due to the large number of potentially efficient therapies. Careful patient selection and a tailored treatment modality for every patient, either potentially curative (surgical treatment and tumor ablation) or palliative (transarterial therapy, radioembolization and medical treatment, i.e., sorafenib) is mandatory to achieve the best treatment outcome.

Metabolic serum biomarkers for the prediction of cancer: a follow-up of the studies conducted in the Swedish AMORIS study

The Swedish Apolipoprotein MOrtality RISk study (AMORIS) contains information on more than 500 biomarkers collected from 397,443 men and 414,630 women from the greater Stockholm area during the period 1985–1996. Using a ten-digit personal identification code, this database has been linked to Swedish national registries, which provide data on socioeconomic status, vital status, cancer diagnosis, comorbidity, and emigration. Within AMORIS, 18 studies assessing risk of overall and site-specific cancers have been published, utilising a range of serum markers representing glucose and lipid metabolism, immune system, iron metabolism, liver metabolism, and bone metabolism. This review briefly summarises these findings in relation to more recently published studies and provides an overview of where we are today and the challenges of observational studies when studying cancer risk prediction.

Overall, more recent observational studies supported previous findings obtained in AMORIS, although no new results have been reported for serum fructosamine and inorganic phosphate with respect to cancer risk. A drawback of using serum markers in predicting cancer risk is the potential fluctuations following other pathological conditions, resulting in non-specificity and imprecision of associations observed. Utilisation of multiple combination markers may provide more specificity, as well as give us repeated instead of single measurements. Associations with other diseases may also necessitate further analytical strategies addressing effects of serum markers on competing events in addition to cancer. Finally, delineating the role of serum metabolic markers may generate valuable information to complement emerging clinical studies on preventive effects of drugs and supplements targeting metabolic disorders against cancer.

Nonalcoholic fatty liver disease increases the risk of hepatocellular carcinoma in patients with alcohol-associated cirrhosis awaiting liver transplants

BACKGROUND & AIMS

Many patients with alcohol-associated cirrhosis also have diabetes, obesity, or insulin resistance-mediated steatosis, but little is known about how these disorders affect the severity of liver disease. We analyzed the prevalence and prognostic implications of metabolic risk factors (MRFs) such as overweight, diabetes, dyslipidemia, and hypertension in patients with alcohol-associated cirrhosis awaiting liver transplants.

METHODS

We performed a retrospective study of 110 patients with alcohol-associated cirrhosis (77% male; mean age, 55 y; 71% with >6 mo of abstinence) who received liver transplants at a single center in Paris, France, from 2000 through 2013. We collected data on previous exposure to MRFs, steatosis (>10% in the explant), and histologically confirmed hepatocellular carcinoma (HCC).

RESULTS

HCC was detected in explants from 29 patients (26%). Steatosis was detected in explants from 47 patients (70% were abstinent for ≥6 mo); 50% had a history of overweight or type 2 diabetes. Fifty-two patients (47%) had a history of MRFs and therefore were at risk for nonalcoholic fatty liver disease. A higher proportion of patients with MRF had HCC than those without MRF (46% vs 9%; P < .001). A previous history of overweight or type 2 diabetes significantly increased the risk for HCC (odds ratio, 6.23; 95% confidence interval [CI], 2.47-15.76, and odds ratio, 4.63; 95% CI, 1.87-11.47, respectively; P < .001). MRF, but not steatosis, was associated with the development of HCC (odds ratio, 11.76; 95% CI, 2.60-53; P = .001) independent of age, sex, amount of alcohol intake, or severity of liver disease.

CONCLUSIONS

Patients with alcohol-associated cirrhosis who received transplants frequently also had nonalcoholic fatty liver disease. MRFs, particularly overweight, obesity, and type 2 diabetes, significantly increase the risk of HCC.

Metabolic risk score and cancer risk: pooled analysis of seven cohorts

Background: There are few data on the joint influence of metabolic factors on risk of separate cancers.

Methods: We analysed data on body mass index, blood pressure and plasma levels of glucose, total cholesterol and triglycerides from seven European cohorts comprising 564 596 men and women with a mean age of 44 years. We weighted those factors equally into a standardized metabolic risk score [MRS, mean = 0, standard deviation (SD) = 1], with an individual’s level indicated as SDs from the sex- and cohort-specific means. Cancer hazard ratios were calculated by Cox regression with age as timescale and with relevant adjustments including smoking status. All statistical tests were two-sided.

Results: During a mean follow-up of 12 years, 21 593 men and 14 348 women were diagnosed with cancer. MRS was linearly and positively associated with incident cancer in total and at sites (P < 0.05). In men, risk per SD MRS was increased by 43% (95% confidence interval: 27–61) for renal cell cancer, 43% (16–76) for liver cancer, 29% (20–38) for colon cancer, 27% (5–54) for oesophageal cancer, 20% (9–31) for rectal cancer, 19% (4–37) for leukaemias, 15% (1–30) for oral cancer and 10% (2–19) for bladder cancer. In women, risk increases per SD MRS were 56% (42–70) for endometrial cancer, 53% (29–81) for pancreatic cancer, 40% (16–67) for renal cell cancer, 27% (9–47) for cervical cancer and 17% (3–32) for rectal cancer.

Conclusion: This largest study to date on the joint influence of metabolic factors on risk of separate cancers showed increased risks for several cancers, in particular renal cell and liver cancer in men and endometrial and pancreatic cancer in women.

Clinical features of hepatocellular carcinoma associated with nonalcoholic fatty liver disease: a review of human studies

Most cases of hepatocellular carcinoma (HCC) in Japan develop in the background of chronic liver disease caused by hepatitis C virus (HCV). Recently, however, HCV-associated HCC has been shown to be decreasing, while non-B and non-C HCC (NBNC-HCC), which is negative for HCV and hepatitis B virus infection, has increased. The main cause of NBNC-HCC is alcoholic liver disease, but the recent increase of NBNC-HCC is thought to be due to an increase in patients with nonalcoholic fatty liver disease (NAFLD). Approximately 10% of NAFLD cases involve nonalcoholic steatohepatitis (NASH), and NASH can progress to liver cirrhosis and its associated complications such as HCC. There are no accurate data on the percentage of NASH-related HCC among all-cause HCC in Japan, because no large-scale investigation has been performed. However, the rate is thought to be about 3% of overall HCC, which is lower than that in the United States. The incidence of HCC in patients with NASH-related cirrhosis is thought to be 2% per year, which is lower than that in HCV-related cirrhosis. Risks for NASH-related HCC include advanced hepatic fibrosis, older age, and being male. NAFLD that includes NASH is associated with metabolic syndrome, which includes obesity and diabetes, and metabolic syndrome is a risk factor for HCC. Genetic factors and dietary patterns may also be related to NASH-related HCC. Thus, regular HCC surveillance, as performed for patients with viral chronic liver disease, is required for patients with NAFLD, and diagnostic markers are required for simple, rapid and specific detection of NASH-related HCC.

Simple sugar intake and hepatocellular carcinoma: epidemiological and mechanistic insight

Sugar intake has dramatically increased during the last few decades. Specifically, there has been a clear trend towards higher consumption of fructose and high fructose corn syrup, which are the most common added sugars in processed food, soft drinks and other sweetened beverages. Although still controversial, this rising trend in simple sugar consumption has been positively associated with weight gain and obesity, insulin resistance and type 2 diabetes mellitus and non-alcoholic fatty liver disease. Interestingly, all of these metabolic alterations have also been related to the development of hepatocellular carcinoma. The purpose of this review is to discuss the evidence coming from epidemiological studies and data from animal models relating the consumption of simple sugars, and specifically fructose, with an increased risk of hepatocellular carcinoma and to gain insight into the putative molecular mechanisms involved.

Serum glucose and risk of cancer: a meta-analysis

BACKGROUND

Raised serum glucose has been linked to increased risk of many solid cancers. We performed a meta-analysis to quantify and summarise the evidence for this link.

METHODS

Pubmed and Embase were reviewed, using search terms representing serum glucose and cancer. Inclusion and exclusion criteria focused on epidemiological studies with clear definitions of serum glucose levels, cancer type, as well as well-described statistical methods with sufficient data available. We used 6.1 mmol/L as the cut-off for high glucose, consistent with the WHO definition of metabolic syndrome. Random effects analyses were performed to estimate the pooled relative risk (RR).

RESULTS

Nineteen studies were included in the primary analysis, which showed a pooled RR of 1.32 (95% CI: 1.20 - 1.45). Including only those individuals with fasting glucose measurements did not have a large effect on the pooled RR (1.32 (95% CI: 1.11-1.57). A stratified analysis showed a pooled RR of 1.34 (95% CI: 1.02-1.77) for hormonally driven cancer and 1.21 (95% CI: 1.09-1.36) for cancers thought to be driven by Insulin Growth Factor-1.

CONCLUSION

A positive association between serum glucose and risk of cancer was found. The underlying biological mechanisms remain to be elucidated but our subgroup analyses suggest that the insulin- IGF-1 axis does not fully explain the association. These findings are of public health importance as measures to reduce serum glucose via lifestyle and dietary changes could be implemented in the context of cancer mortality.

Diabetes and cancer: epidemiology and potential mechanisms

Type 2 diabetes mellitus is an independent risk factor for cancer such as pancreatic, liver, colorectal and breast cancer. In addition, diabetes decreases the risk of prostate cancer. These associations have been found in numerous epidemiological studies, among them several prospective cohorts. However, such studies do not prove causality of the association and cannot exclude inadequate correction for known confounders (e.g. visceral fat) or the influence of unknown confounders. Thus, it is unclear whether the cancer risk is increased by the causes (e.g. the metabolic syndrome), the metabolic consequences (e.g. hyperglycaemia) or the therapy of diabetes; a question which is of major importance for therapeutic guidelines. Identification of the potential mechanisms by which the diabetes or its therapy accelerates or inhibits the development of cancer will help answering the question by providing biological plausibility. This review will summarize the evidence supporting the association of cancer and type 2 diabetes and discuss its potential causes.

Targeting p110gamma in gastrointestinal cancers: attack on multiple fronts

Phosphoinositide 3-kinases (PI3Ks) regulate several cellular functions that are critical for cancer progression and development, including cell survival, proliferation and migration. Three classes of PI3Ks exist with the class I PI3K encompassing four isoforms of the catalytic subunit known as p110α, p110β, p110γ, and p110δ. Although for many years attention has been mainly focused on p110α recent evidence supports the conclusion that p110β, p110γ, and p110δ can also have a role in cancer. Amongst these, accumulating evidence now indicates that p110γ is involved in several cellular processes associated with cancer and indeed this specific isoform has emerged as a novel important player in cancer progression. Studies from our laboratory have identified a specific overexpression of p110γ in human pancreatic ductal adenocarcinoma (PDAC) and in hepatocellular carcinoma (HCC) tissues compared to their normal counterparts. Our data have further established that selective inhibition of p110γ is able to block PDAC and HCC cell proliferation, strongly suggesting that pharmacological inhibition of this enzyme can directly affect growth of these tumors. Furthermore, increasing evidence suggests that p110γ plays also a key role in the interactions between cancer cells and tumor microenvironment and in particular in tumor-associated immune response. It has also been reported that p110γ can regulate invasion of myeloid cells into tumors and tumor angiogenesis. Finally p110γ has also been directly involved in regulation of cancer cell migration. Taken together these data indicate that p110γ plays multiple roles in regulation of several processes that are critical for tumor progression and metastasis. This review will discuss the role of p110γ in gastrointestinal tumor development and progression and how targeting this enzyme might represent a way to target very aggressive tumors such as pancreatic and liver cancer on multiple fronts.

Hepatocellular carcinoma: epidemiology and risk factors

Hepatocellular carcinoma is one of the major malignant tumors in the world today. The number of new cases of the tumor increases year by year, and hepatocellular carcinoma almost always runs a fulminant course and carries an especially grave prognosis. It has a low resectability rate and a high recurrence rate after surgical intervention, and responds poorly to anticancer drugs and radiotherapy. Hepatocellular carcinoma does not have a uniform geographical distribution: rather, very high incidences occur in Eastern and Southeastern Asia and in sub-Saharan Black Africans. In these regions and populations, the tumor shows a distinct shift in age distribution toward the younger ages, seen to greatest extent in sub-Saharan Black Africans. In all populations, males are more commonly affected. The most common risk factors for hepatocellular carcinoma in resource-poor populations with a high incidence of the tumor are chronic hepatitis B virus infection and dietary exposure to the fungal hepatocarcinogen aflatoxin B1. These two causative agents act either singly or synergistically. Both the viral infection and exposure to the fungus occur from early childhood, and the tumor typically presents at an early age. Chronic hepatitis C virus infection is an important cause of hepatocellular carcinoma in resource-rich countries with a low incidence of the tumor. The infection is acquired in adulthood and hepatocellular carcinoma occurs later than it does with hepatitis B virus-induced tumors. In recent years, obesity and the metabolic syndrome have increased markedly in incidence and importance as a cause of hepatocellular carcinoma in some resource-rich regions. Chronic alcohol abuse remains an important risk factor for malignant transformation of hepatocytes, frequently in association with alcohol-induced cirrhosis. Excessive iron accumulation in hereditary hemochromatosis and dietary iron overload in the Black African population and membranous obstruction of the inferior cava cause the tumor in a few countries.