Risk of hepatocellular carcinoma in diabetic patients and risk reduction associated with anti-diabetic therapy: a population-based cohort study

The diagnosis and treatment of hepatocellular carcinoma

BACKGROUND

The incidence of hepatocellular carcinoma (HCC) has continued to rise in recent years. This increase has been attributed to alcohol-induced liverdiseases, metabolic syndrome, and the rising number of hepatitis B and C viral infections.

METHOD

Pertinent publications (2000-2011) were retrieved by a systematic Medline search. In seven different subject areas, 41 key questions were defined; 15 of them were answered on the basis of a primary search. In addition, original-source guidelines that are currently available from around the world were assessed and utilized with the aid of a systematic instrument for the evaluation of guidelines (DELBI).

RESULTS

All patients with chronic liver disease should undergo ultrasonography every six months for the early detection of HCC. Measurement of the alphafetoprotein (AFP) concentration is not obligatory, as this test is relatively insensitive when used for early detection. If ultrasonography reveals a mass, a tomographic imaging study with contrast should be obtained; the latter may reveal a characteristic pattern of contrast enhancement that can be accepted as definitive evidence of HCC. Fine-needle biopsy has a sensitivity and specificity of over 90% for the diagnosis of HCC. Any patient in whom HCC has been diagnosed should be referred to a center where potentially curative treatments (surgery, transplantation, local ablation) can be considered. Radiofrequency ablation (RFA) is now performed instead of percutaneous ethanol instillation. For patients with advanced tumors, sorafenib should only be offered to those in Child-Pugh stage A. This drug has been found to prolong mean overall survival from 7.9 to 10.7 months.

CONCLUSION

HCC poses particular diagnostic and therapeutic challenges that are best met with an interdisciplinary management approach.

Cancer risk in HBV patients with statin and metformin use: a population-based cohort study

Chronic infection with hepatitis B virus (HBV) often causes chronic inflammation of the liver with an increased incidence of hepatocellular carcinoma (HCC). HBV-infected individuals may also have an increased incidence of nonliver cancers. Taking statin or metformin may decrease inflammation and infiltration, which may, as a result, reduce the risk of liver cancer or other major cancers in patients with HBV infection. The purpose of this study was to evaluate the hypothesis that statin and metformin could reduce the incidence of liver cancer (HCC) or nonliver cancers in patients with HBV.Using the Taiwan Longitudinal Health Insurance Database 2000 to 2008, this cohort study comprised patients with a recorded diagnosis of HBV (N = 71,847) between January 1, 2000 and December 31, 2008. Each patient was followed-up until the end of 2008. The occurrence of HCC or a nonliver cancer was evaluated in patients who either were or were not taking statin or metformin. Cox proportional hazard regressions were used to evaluate the cancer incidence after adjusting for known confounding factors.In total, 71,824 HBV-infected patients comprised the study cohort. Our study showed that either metformin or statin use was associated with a reduction in the incidence of cancer. This was most prominent in patients taking both statin and metformin. The adjusted hazard ratios (HRs) for patients using only statin were 0.52 (95% confidence interval [CI], 0.48-0.57) for all cancers, 0.28 (95% CI, 0.23-0.35) for liver cancer, and 0.63 (95% CI, 0.57-0.70) for nonliver cancers. Patients taking only metformin had risk-adjusted HRs of 0.82 (95% CI, 0.75-0.90) for all cancers, 0.97 (95% CI, 0.84-1.14) for liver cancer, and 0.75 (95% CI, 0.67-0.84) for nonliver cancers. A dose-dependent effect of statin use for chemoprevention was observed for all cancers, including both liver cancer and nonliver cancers. A dose-dependent effect of metformin was also seen in liver cancer and nonliver cancers without stratification into different cumulative daily doses of statin use.This population-based cohort study investigated the protective effect of statin and metformin against cancer events in patients with HBV infection. Our study demonstrated that either statin or metformin served as independent chemopreventive agents with a dose-response effect in reducing the incidence of cancer with a dose-response effect of the agents and an additive or synergistic effect of combining statin and metformin use in reducing the incidence of many cancers.

Attributable causes of liver cancer mortality and incidence in china

OBJECTIVES

To estimate the proportion of liver cancer cases and deaths due to infection with hepatitis B virus (HBV), hepatitis C virus (HCV), aflatoxin exposure, alcohol drinking and smoking in China in 2005.

STUDY DESIGN

Systemic assessment of the burden of five modifiable risk factors on the occurrence of liver cancer in China using the population attributable fraction.

METHODS

We estimated the population attributable fraction of liver cancer caused by five modifiable risk factors using the prevalence data around 1990 and data on relative risks from meta-analyses, and large-scale observational studies. Liver cancer mortality data were from the 3rd National Death Causes Survey, and data on liver cancer incidence were estimated from the mortality data from cancer registries in China and a mortality/incidence ratio calculated.

RESULTS

We estimated that HBV infection was responsible for 65.9% of liver cancer deaths in men and 58.4% in women, while HCV was responsible for 27.3% and 28.6% respectively. The fraction of liver cancer deaths attributable to aflatoxin was estimated to be 25.0% for both men and women. Alcohol drinking was responsible for 23.4% of liver cancer deaths in men and 2.2% in women. Smoking was responsible for 18.7% and 1.0% . Overall, 86% of liver cancer mortality and incidence (88% in men and 78% in women) was attributable to these five modifiable risk factors.

CONCLUSIONS

HBV, HCV, aflatoxin, alcohol drinking and tobacco smoking were responsible for 86% of liver cancer mortality and incidence in China in 2005. Our findings provide useful data for developing guidelines for liver cancer prevention and control in China and other developing countries.

Diabetes and Hepatitis C: A Two-Way Association

Diabetes and hepatitis C infection are both prevalent diseases worldwide, and are associated with increased morbidity and mortality. Most studies, but not all, have shown that patients with chronic hepatitis C are more prone to develop type 2 diabetes (T2D) compared to healthy controls, as well as when compared to patients with other liver diseases, including hepatitis B. Furthermore, epidemiological studies have revealed that patients with T2D may also be at higher risk for worse outcomes of their hepatitis C infection, including reduced rate of sustained virological response, progression to fibrosis and cirrhosis, and higher risk for development of hepatocellular carcinoma. Moreover, hepatitis C infection and mainly its treatment, interferon α, can trigger the development of type 1 diabetes. In this review, we discuss the existing data on this two-way association between diabetes and hepatitis C infection with emphasis on possible mechanisms. It remains to be determined whether the new curative therapies for chronic hepatitis C will improve outcomes in diabetic hepatitis C patients, and conversely whether treatment with Metformin will reduce complications from hepatitis C virus infection. We propose an algorithm for diabetes screening and follow-up in hepatitis C patients.

Metabolic syndrome in chronic hepatitis C infection: does it still matter in the era of directly acting antiviral therapy?

Metabolic syndrome is prevalent in patients with hepatitis C virus (HCV) infection. Given the pandemic spread of HCV infection and metabolic syndrome, the burden of their interaction is a major public health issue. The presence of metabolic syndrome accelerates the progression of liver disease in patients with HCV infection. New drug development in HCV has seen an unprecedented rise in the last year, which resulted in better efficacy, better tolerance, and a shorter treatment duration. This review describes the underlying mechanisms and clinical effects of metabolic syndrome in HCV infection, as well as their importance in the era of new directly acting antiviral therapy.

Hyperglycemia and chronic liver diseases on risk of hepatocellular carcinoma in Chinese patients with type 2 diabetes--National cohort of Taiwan Diabetes Study

This study examined whether glycated hemoglobin A1C (HbA1C) and chronic liver diseases are associated with hepatocellular carcinoma (HCC) risk in Type 2 diabetic patients. A retrospective cohort study consisting of 51,705 patients with Type 2 diabetes aged 30 and over enrolled in the National Diabetes Care Management Program before 2004 was used in Cox proportional hazards models. HbA1C was independently associated with HCC incidence, and multivariate-adjusted hazard ratio (HR) of HCC was 1.20 (95% confidence interval, CI: 1.02-1.41) for patients with a level of HbA1c ≥ 9% compared with patients with a level of HbA1c <7% after multivariate adjustment. We observed a significant linear trend in HCC incidence with increasing HbA1c (p for trend = 0.02, HR = 1.07, 95% CI = 1.01-1.12 for every 1% increment in HbA1c). We observed significant HRs of HCC for patients with a level of HbA1c ≥ 9% with alcoholic liver damage, liver cirrhosis, HBV, HCV and any one of chronic liver diseases compared with patients with a level of HbA1c <9% and no counterpart comorbidity in the entire sample (HR = 8.63, 95% CI = 1.41-52.68; HR = 5.02, 95% CI = 3.10-8.12; HR = 2.53, 95% CI = 1.10-5.85; HR = 1.79, 95% CI = 1.01-3.17; and HR = 3.59, 95% CI = 2.56-5.02, respectively). Our results suggest significant joint associations of HbA1c ≥ 9% and chronic liver diseases. Lifestyle or treatment interventions such as maintaining a satisfactory glycemic control and chronic liver diseases may reduce the burden of HCC.

Diabetes in China: a societal solution for a personal challenge

China has a large burden of diabetes: in 2013, one in four people with diabetes worldwide were in China, where 11·6% of adults had diabetes and 50·1% had prediabetes. Many were undiagnosed, untreated, or uncontrolled. This epidemic is the result of rapid societal transition that has led to an obesogenic environment against a backdrop of traditional lifestyle and periods of famine, which together puts Chinese people at high risk of diabetes and multiple morbidities. Societal determinants including social disparity and psychosocial stress interact with factors such as low-grade infection, environmental pollution, care fragmentation, health illiteracy, suboptimal self-care, and insufficient community support to give rise to diverse subphenotypes and consequences, notably renal dysfunction and cancer. In the China National Plan for Non-Communicable Disease Prevention and Treatment (2012-15), the Chinese Government proposed use of public measures, multisectoral collaborations, and social mobilisation to create a health-enabling environment and to reform the health-care system. While awaiting results from these long-term strategies, we advocate the use of a targeted and proactive approach to identify people at high risk of diabetes for prevention, and of private-public-community partnerships that make integrated care more accessible and sustainable, focusing on registry, empowerment, and community support. The multifaceted nature of the societal and personal challenge of diabetes requires a multidimensional solution for prevention in order to reduce the growing disease burden.

Effect of pioglitazone on outcome following curative treatment for hepatocellular carcinoma in patients with hepatitis C virus infection: A prospective study

Pioglitazone is an insulin sensitizer used for the treatment of diabetes mellitus (DM). DM with insulin resistance is a risk factor for hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV) infection. We aimed to investigate the effects of pioglitazone on HCC recurrence following treatment in HCV-infected patients. Between 2009 and 2011, 85 HCV-infected HCC patients who underwent curative treatment were enrolled in this prospective study. Among 45 patients with type 2 DM, 27 were administered pioglitazone (pioglitazone group) following treatment. The remaining 58 patients were assigned to the control group. The primary outcome was recurrence-free survival. Changes in insulin resistance and serum adiponectin levels resulting from pioglitazone treatment were also assessed. In the whole analysis (n=85), no significant difference in recurrence-free survival was observed between the pioglitazone and control groups. However, in a spline model analysis of DM patients, a decreased risk of HCC recurrence was associated with increased body weight in patients with a body mass index (BMI) ≥23; this association became significant at BMI ≥24 (hazard ratio=0.17; 95% confidence interval: 0.03-0.95). In addition, significantly decreased homeostasis model assessment for insulin resistance values (P=0.002) and significantly increased serum high-molecular-weight adiponectin levels (P<0.001) were observed following pioglitazone treatment. Although pioglitazone did not suppress HCC recurrence in the whole analysis, it inhibited HCC recurrence in overweight HCV-infected diabetic patients. Moreover, pioglitazone improved insulin resistance and adipocytokine levels. Thus, pioglitazone may suppress HCC recurrence, which is associated with glucose and fat metabolism disorders.

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

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

Emerging role of the peroxisome proliferator-activated receptor-gamma in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the major leading cause of cancer death worldwide. Hepatitis B virus, hepatitis C virus, alcohol consumption, non-alcoholic fatty liver disease, and diabetes are the major risks for developing HCC. Until now, recurrence and metastasis are the major cause of death in HCC patients. Therefore, identification of new effective molecular targets is an urgent need for treatment of HCC. Peroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated nuclear receptor which could be activated by PPARγ agonists such as thiazolidinediones, and natural PPARγ ligand (such as 15-deoxy-Δ12,14-prostaglandin J₂, 15d-PGJ₂). Increasing in vitro and in vivo evidence has demonstrated that PPARγ agonists exhibit an inhibitory role on tumor cell growth, migration, and invasion, suggesting that PPARγ activation may play an important role in the regulation of growth of HCC. It has been reported that PPARγ activation by thiazolidinediones or overexpression of PPARγ by virus-mediated gene transfer has shown growth inhibitory effects in hepatoma cells, but the expression level of PPARγ in HCC tissues still remains conflicting. Notably, a novel PPARγ agonist, honokiol, has recently been found to activate the PPARγ/RXR heterodimer, and has also exhibited significant anti-cancer effects in hepatoma cells. In the present review, we summarized studies on the role and the molecular regulation of PPARγ in HCC development in vitro and in vivo. PPARγ has the potential to be a therapeutic target for future treatment of HCC.

Use of insulin and insulin analogs and risk of cancer - systematic review and meta-analysis of observational studies

Background:

An association of insulin use and risk of cancer has been reported but evidence is conflicting and methodological issues have been identified.

Objective:

To summarize results regarding insulin use and cancer risk by a systematic review and meta-analysis of cohort and case-control studies examining risk of cancer associated with insulin use in patients with diabetes.

Data Sources:

Systematic literature search in 5 databases: PubMed, Embase, Web of Science, Scopus and Cochrane Library.

Study Eligibility Criteria (PICOS):

Population: diabetes patients. Exposure: Users of any exogenous insulin. Comparison: Diabetes patients with or without use of antidiabetic drugs. Outcome: Any incident cancer. Study Design: Cohort and case-control studies.

Results:

42 eligible studies examined risk of any cancer and 27 site-specific cancers. Results of individual studies were heterogeneous. Meta-analyses were significant for: Insulin vs No Insulin: Increased risk for pancreas, liver, kidney, stomach and respiratory cancer, decreased risk for prostate cancer. Insulin vs Non-Insulin Antidiabetics: Increased risk for any, pancreatic and colorectal cancer. Glargine vs Non-Glargine Insulin: Increased risk for breast cancer, decreased risk for colon cancer.

Limitations:

Few studies available for most cancer sites and exposure contrasts, and few assess effect of dose and duration of exposure. Methodological issues in several studies. Availability of confounders.

Conclusions:

Insulin use was associated with risk of cancer at several sites. Cautious interpretation of results is warranted as methodological issues and limitations in several of the included studies have been identified. Choice of study design may have a profound effect on estimated cancer risk.

Non-alcoholic fatty liver disease and diabetes: From physiopathological interplay to diagnosis and treatment

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent in patients with diabetes mellitus and increasing evidence suggests that patients with type 2 diabetes are at a particularly high risk for developing the progressive forms of NAFLD, non-alcoholic steatohepatitis and associated advanced liver fibrosis. Moreover, diabetes is an independent risk factor for NAFLD progression, and for hepatocellular carcinoma development and liver-related mortality in prospective studies. Notwithstanding, patients with NAFLD have an elevated prevalence of prediabetes. Recent studies have shown that NAFLD presence predicts the development of type 2 diabetes. Diabetes and NAFLD have mutual pathogenetic mechanisms and it is possible that genetic and environmental factors interact with metabolic derangements to accelerate NAFLD progression in diabetic patients. The diagnosis of the more advanced stages of NAFLD in diabetic patients shares the same challenges as in non-diabetic patients and it includes imaging and serological methods, although histopathological evaluation is still considered the gold standard diagnostic method. An effective established treatment is not yet available for patients with steatohepatitis and fibrosis and randomized clinical trials including only diabetic patients are lacking. We sought to outline the published data including epidemiology, pathogenesis, diagnosis and treatment of NAFLD in diabetic patients, in order to better understand the interplay between these two prevalent diseases and identify the gaps that still need to be fulfilled in the management of NAFLD in patients with diabetes mellitus.

Safety and efficacy of metformin in patients with type 2 diabetes mellitus and chronic hepatitis C

OBJECTIVE

To evaluate the safety and efficacy of metformin in patients with type 2 diabetes mellitus (T2DM) and chronic hepatitis C virus (HCV) with or without cirrhosis and hepatocellular carcinoma (HCC).

DATA SOURCES

A PubMed (1946-August 2013) search using the keywords type 2 diabetes mellitus, metformin, hepatitis C virus, cirrhosis, and hepatocellular carcinoma was conducted. The references in published articles were reviewed to identify additional references for inclusion.

STUDY SELECTION AND DATA EXTRACTION

Studies written in English, evaluating metformin use in human patients with T2DM and chronic HCV were included.

DATA SYNTHESIS

Eight studies met criteria for inclusion. Two prospective, randomized controlled trials showed increased benefit with metformin on virological response in patients with insulin resistance receiving HCV treatment. A prospective observational study evaluated metformin exclusively in patients with T2DM and HCV and showed significant reductions in the occurrence of HCC, liver-related death, and liver transplant. Four retrospective case control studies showed a decreased risk of HCC with metformin treatment in patients with T2DM and chronic liver disease. Finally, a retrospective cohort study indicated an increased survival rate in patients with diabetes and HCC undergoing radiofrequency ablation. Although diarrhea was increased in patients receiving metformin, no serious adverse effects, including lactic acidosis, were reported.

CONCLUSIONS

Metformin may provide benefit in the treatment of HCV and in reducing the risk of HCC in patients with T2DM and HCV. Further long-term, randomized controlled trials are needed to adequately assess the safety and efficacy of metformin therapy in patients with comorbid diabetes and chronic HCV.

Metformin and cancer risk and mortality: a systematic review and meta-analysis taking into account biases and confounders

Treatment of diabetics with metformin is associated with decreased breast cancer risk in observational studies, but it remains unclear if this drug has clinical antineoplastic activity. In a recent presurgical trial, we found a heterogeneous effect of metformin on breast cancer proliferation (ki-67) depending upon insulin resistance (HOMA index). Here, we determined the associations of additional serum biomarkers of insulin resistance, tumor subtype, and drug concentration with ki-67 response to metformin. Two-hundred non-diabetic women were randomly allocated to metformin (850 mg/bid) or placebo for 4 weeks prior to breast cancer surgery. The ki-67 response to metformin was assessed comparing data obtained from baseline biopsy (ki-67 and tumor subtype) and serum markers (HOMA index, C-peptide, IGF-I, IGFBP-1, IGFBP-3, free IGF-I, hs-CRP, adiponectin) with the same measurements at definitive surgery. For patients with a blood sample taken within 24 h from last drug intake, metformin level was measured. Compared with placebo, metformin significantly decreased ki-67 in women with HOMA > 2.8, those in the lowest IGFBP-1 quintile, those in the highest IGFBP-3 quartile, those with low free IGF-I, those in the top hs-CRP tertile, and those with HER2-positive tumors. In women with HOMA index > 2.8, drug levels were positively correlated with the ki-67 decrease, whereas no trend was noted in women with HOMA < 2.8 (p-interaction = 0.07). At conventional antidiabetic doses, the effect of metformin on tumor ki-67 of non-diabetic breast cancer patients varies with host and tumor characteristics. These findings are relevant to design breast cancer prevention and treatment trials with metformin.

Metformin and cancer risk and mortality: a systematic review and meta-analysis taking into account biases and confounders

Previous meta-analyses have shown that the antidiabetic agent metformin is associated with reduced cancer incidence and mortality. However, this effect has not been consistently demonstrated in animal models and recent epidemiologic studies. We performed a meta-analysis with a focus on confounders and biases, including body mass index (BMI), study type, and time-related biases. We identified 71 articles published between January 1, 1966, and May 31, 2013, through Pubmed, ISI Web of Science (Science Citation Index Expanded), Embase, and the Cochrane library that were related to metformin and cancer incidence or mortality. Study characteristics and outcomes were abstracted for each study that met inclusion criteria. We included estimates from 47 independent studies and 65,540 cancer cases in patients with diabetes. Overall cancer incidence was reduced by 31% [summary relative risk (SRR), 0.69; 95% confidence interval (CI), 0.52-0.90], although between-study heterogeneity was considerable (I(2) = 88%). Cancer mortality was reduced by 34% (SRR, 0.66; 95% CI, 0.54-0.81; I(2) = 21%). BMI-adjusted studies and studies without time-related biases also showed significant reduction in cancer incidence (SRR, 0.82; 95% CI, 0.70-0.96 with I(2) = 76% and SRR, 0.90; 95% CI, 0.89-0.91 with I(2) = 56%, respectively), albeit with lesser magnitude (18% and 10% reduction, respectively). However, studies of cancer mortality and individual organ sites did not consistently show significant reductions across all types of analyses. Although these associations may not be causal, our results show that metformin may reduce cancer incidence and mortality in patients with diabetes However, the reduction seems to be of modest magnitude and not affecting all populations equally. Clinical trials are needed to determine if these observations apply to nondiabetic populations and to specific organ sites.

Latest insights into the risk of cancer in diabetes

A growing body of evidence from observational studies and meta‐analyses of the data suggest that diabetes mellitus is associated with an increased risk of cancer. Meta‐analyses have shown that diabetes increases the risks of total cancer, and of site‐specific cancers of the breast, endometrium, bladder, liver, colorectum and pancreas, and that it decreases the risk of prostate cancer. Insulin resistance and secondary hyperinsulinemia is the most frequently proposed hypothesis, and hyperglycemia itself might promote carcinogenesis. In addition to several facets of lifestyle including obesity, smoking and lack of exercise, treatment for diabetes might affect the risk of cancer. For instance, metformin, an insulin sensitizer, reportedly has a potential anticancer effect. In light of the exploding global epidemic of diabetes, even a modest increase in the cancer risk will translate into a substantial socioeconomic burden. The current insights underscore the need for clinical attention and better‐designed studies of the complex interactions between diabetes and cancer.

Nutrition and metabolism in hepatocellular carcinoma

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

Pyogenic liver abscess in end-stage renal disease patients: a nationwide longitudinal study

End-stage renal disease (ESRD) patients are more prone to infectious disease because of their immunocompromised status. However, the association between pyogenic liver abscess (PLA) and ESRD remains not clear. The aim of our study is to evaluate the incidence, risk factors, and outcomes of PLA in ESRD patients. We recruited all incident ESRD patients from the Taiwan National Health Insurance database from 1998 to 2006. The incidence rate of PLA in ESRD patients was compared with that of a randomly selected non-ESRD control group matched for age, sex gender, Charlson comorbidity score, diabetes mellitus, and cirrhosis. Among the 57,761 incident dialysis patients, there were 538 cases of PLA. The incidence rate of PLA was 18.20 per 10,000 person-years in the ESRD cohort and 6.34 per 10,000 person-years in matched control cohort. The rate of PLA was significantly higher in the ESRD cohort (hazard ratio 3.63, 95% confidence interval 2.83-4.65, P < 0.001). The mortality rates of PLA were higher in the ESRD cohort than those in matched control cohort. Diabetes mellitus was an independent risk factor for mortality of PLA. Compared with non-ESRD patients, ESRD patients have a higher risk of PLA and poorer outcomes.

Obesity and non-alcoholic fatty liver disease: Disparate associations among Asian populations

Obesity is a global epidemic contributing to an increasing prevalence of obesity-related systemic disorders, including nonalcoholic fatty liver disease. The rising prevalence of nonalcoholic steatohepatitis (NASH) will in the near future lead to end-stage liver disease in a large cohort of patients with NASH-related cirrhosis and NASH is predicted to be a leading indication for liver transplantation in the coming decade. However, the prevalence of obesity and the progression of hepatic histological damage associated with NASH exhibit significant ethnic disparities. Despite a significantly lower body mass index and lower rates of obesity compared to other ethnic groups, Asians continue to demonstrate a significant prevalence of hypertension, diabetes, metabolic syndrome and NASH. Ethnic disparities in central adiposity and visceral fat distribution have been hypothesized to contribute to these ethnic disparities. The current review focuses on the epidemiology of obesity and NASH among Asian populations.

Diabetes mellitus and poorer prognosis in hepatocellular carcinoma: a systematic review and meta-analysis

Background

Previous studies suggested that diabetes mellitus was associated with cancer risk and prognosis, but studies investigating the relationship between diabetes mellitus and survival in patients with hepatocellular carcinoma (HCC) reported inconsistent findings. To derive a more precise estimate of the prognostic role of diabetes mellitus in HCC, we systematically reviewed published studies and carried out a meta-analysis.

Methods

Eligible articles were identified in electronic databases from their inception through September 16, 2013. To evaluate the correlation between diabetes mellitus and prognosis in HCC, the pooled hazard ratios (HR) and their 95% confidence intervals (95% CI) for poorer overall and disease-free survivals were calculated by standard meta-analysis techniques with fixed-effects or random-effects models.

Results

21 studies with a total of 9,767 HCC patients stratifying overall survival and/or disease-free survival in HCC patients by diabetes mellitus status were eligible for meta-analysis. 20 studies with a total of 9,727 HCC cases investigated the overall survival, and 10 studies with a total of 2,412 HCC patients investigated the disease-free survival. The pooled HRs for overall survival and disease-free survival were 1.46 (95% CI, 1.29 to 1.66; P<0.001) and 1.57 (95% CI, 1.21 to 2.05; P = 0.001), respectively. The adjusted HRs for overall survival and disease-free survival were 1.55 (95% CI, 1.27 to 1.91; P<0.001) and 2.15 (95% CI, 1.75 to 2.63; P<0.001), respectively. In addition, for patients receiving hepatic resection, diabetes mellitus was associated with both poorer overall survival and poorer disease-free survival, and for patients receiving non-surgical treatment or patients receiving radiofrequency ablation, diabetes mellitus was associated with poorer overall survival. There was no evidence for publication bias.

Conclusion

Diabetes mellitus is independently associated with both poorer overall survival and poorer disease-free survival in HCC patients.

Additive effects of blood glucose lowering drugs, statins and renin-angiotensin system blockers on all-site cancer risk in patients with type 2 diabetes

BACKGROUND

Hyperglycemia is associated with increased risk of all-site cancer that may be mediated through activation of the renin-angiotensin-system (RAS) and 3-hydroxy-3-methyl-glutaryl-coenzyme-A-reductase (HMGCR) pathways. We examined the joint associations of optimal glycemic control (HbA1c <7%), RAS inhibitors and HMGCR inhibitors on cancer incidence in patients with type 2 diabetes.

METHODS

Patients with type 2 diabetes, with or without a history of cancer or prior exposure to RAS or HMGCR inhibitors at baseline were observed between 1996 and 2005. All patients underwent a comprehensive assessment at baseline and were followed until the censored date at 2005 or their death.

RESULTS

After a median follow-up period of 4.91 years (interquartile range, 2.81 to 6.98), 271 out of 6,103 patients developed all-site cancer. At baseline, patients with incident cancers were older, had longer disease duration of diabetes, higher alcohol and tobacco use, and higher systolic blood pressure and albuminuria, but lower triglyceride levels and estimated glomerular filtration rate (P <0.05). Patients who developed cancers during follow-up were less likely to have started using statins (22.5% versus 38.6%, P <0.001), fibrates (5.9% versus 10.2%, P = 0.02), metformin (63.8% versus 74.5%, P <0.001) or thiazolidinedione (0.7% versus 6.8%, P <0.001) than those who remained cancer-free. After adjusting for co-variables, new treatment with metformin (hazard ratio: 0.39; 95% confidence interval: 0.25, 0.61; P <0.001), thiazolidinedione (0.18; 0.04, 0.72; P = 0.015), sulphonylurea (0.44; 0.27, 0.73; P = 0.014), insulin (0.58; 0.38, 0.89; P = 0.01), statins (0.47; 0.31, 0.70; P <0.001) and RAS inhibitors (0.55; 0.39, 0.78; P <0.001) were associated with reduced cancer risk. Patients with all three risk factors of HbA1c ≥7%, non-use of RAS inhibitors and non-use of statins had four-fold adjusted higher risk of cancer than those without any risk factors (incidence per 1,000-person-years for no risk factors: 3.40 (0.07, 6.72); one risk factor: 6.34 (4.19, 8.50); two risk factors: 8.40 (6.60, 10.20); three risk factors: 13.08 (9.82, 16.34); P <0.001).

CONCLUSIONS

Hyperglycemia may promote cancer growth that can be attenuated by optimal glycemic control and inhibition of the RAS and HMGCR pathways.

Increased risk of pulmonary tuberculosis among patients with appendectomy in Taiwan

The aim of this study was to determine whether there is a relationship between appendectomy and pulmonary tuberculosis in Taiwan. We designed a case-control study by analyzing the database from the Taiwan National Health Insurance Program. In total, we found 11,366 individuals (aged 20 years and older) with newly diagnosed pulmonary tuberculosis as the case group and 45,464 individuals without pulmonary tuberculosis as the control group from 1998 to 2011. The case group and the control group were matched on sex, age, and index year of diagnosing pulmonary tuberculosis. Using the multivariable unconditional logistic regression model, we measured the odds ratio (OR) and 95 % confidence interval (CI) for the risk of pulmonary tuberculosis associated with appendectomy and other comorbidities. After controlling for covariables, the multivariable unconditional logistic regression model disclosed that the OR of pulmonary tuberculosis was 1.4 in appendectomized patients (95 % CI = 1.13, 1.75) when compared to individuals without appendectomy. In further analysis, comorbidity with chronic obstructive pulmonary diseases (OR = 4.63, 95 % CI = 3.21, 6.68), pneumoconiosis (OR = 7.80, 95 % CI = 1.43, 42.5), chronic kidney diseases (OR = 5.65, 95 % CI = 1.79, 17.8), or diabetes mellitus (OR = 2.11, 95 % CI = 1.30, 3.44) increased the risk of pulmonary tuberculosis in appendectomized patients. Individuals with appendectomy are at a 1.4-fold increased risk of pulmonary tuberculosis. Comorbidities, including chronic obstructive pulmonary disease, pneumoconiosis, chronic kidney diseases, and diabetes mellitus, enhance the risk of pulmonary tuberculosis.

Risk profile of hepatocellular carcinoma reveals dichotomy among US veterans

BACKGROUND

Hepatocellular carcinoma (HCC) is traditionally associated with chronic liver injury resulting from hepatitis B virus (HBV) and hepatitis C virus (HCV) infection or excessive consumption of alcohol. In addition, recent evidence links HCC to diabetes.

AIMS

Since these risk factors are prevalent among US veterans, we analyzedcontribution of various etiologies toHCC incidence in this population.

METHODS

Clinicopathological correlates of 150 male US veterans diagnosed with HCC between 2001 and 2010 were analyzed and compared to frequency-matched (2:1) non-cancer controls in a single center.

RESULTS

HCC was associated with cirrhosis (odds ratio [OR], 250.84; 95 % confidence interval [CI], 86.92-723.88; p < 0.0001), chronic hepatitis B (OR, 34.30 95 % CI, 1.97-598.47; p = 0.015), chronic hepatitis C (OR, 6.84; 95 % CI, 3.89-12.04; p < 0.0001), alcohol use (OR, 6.76; 95 % CI, 4.35-10.52; p < 0.0001), and smoking (OR, 1.83; 95 % CI, 1.23-2.89; p = 0.009), but surprisingly not with diabetes. Only in a subgroup of HCC patients with no "traditional" risk factors did diabetes become a strong independent predictor of HCC when compared to HCC patients with at least one such risk factor (OR, 10.69; 95 % CI, 1.88-60.63, p = 0.007). This subgroup was further distinguished by older age, increased prevalence of hypertension, nonsmoking, and a trend to develop noncirrhotic HCC.

CONCLUSIONS

While HCC in US veterans is overwhelmingly linked to cirrhosis due to "traditional" risk factors, it also occurs with a separate clinical profile characterized by diabetes and no evidence of cirrhosis, suggesting distinct mechanisms of hepatocarcinogenesis and needs for surveillance.

The impact of obesity and metabolic syndrome on chronic hepatitis C

The metabolic syndrome and the hepatitis C virus (HCV) infection are 2 global health care challenges with a complex interaction. Insulin resistance, a central component of the metabolic syndrome, is epidemiologically and pathophysiologically intrinsically linked to HCV infection. Insulin resistance and diabetes affect clinical outcomes in patients with liver disease related to HCV, namely, incidence of hepatocellular carcinoma, liver-related mortality, fibrosis progression rate, response to antiviral therapy, and possibly the incidence of cardiovascular events. Viral and metabolic steatosis and its interactions with HCV and the metabolic syndrome are discussed. Management and the need for further research conclude the article.

Splenectomy correlates with increased risk of pulmonary tuberculosis: a case-control study in Taiwan

This study investigated whether there was an association between splenectomy and pulmonary tuberculosis. This was a case-control study using the database of the Taiwan National Health Insurance Programme. We identified 18 960 patients (aged 20 years or older) with newly diagnosed pulmonary tuberculosis as the case group and 73 988 participants without pulmonary tuberculosis as the control group from 1998 to 2011. Both groups were matched for sex, age (per 5 years) and index year of pulmonary tuberculosis diagnosis. The risk of pulmonary tuberculosis associated with splenectomy and other co-morbidities was estimated. After controlling for confounders, multivariable logistic regression analysis showed that the odds of pulmonary tuberculosis were 1.91 in patients with splenectomy (95% CI 1.06-3.44), compared with the participants without splenectomy. Chronic obstructive pulmonary diseases (OR 3.07, 95% CI 2.94-3.21), pneumoconiosis (OR 2.20, 95% CI 1.90-2.56), chronic kidney diseases (OR 1.49, 95% CI 1.33-1.67), diabetes mellitus (OR 1.57, 95% CI 1.50-1.64) and chronic liver diseases (OR 1.31, 95% CI 1.25-1.37) were associated with an increased risk of pulmonary tuberculosis. The sub-analysis demonstrated that the odds of pulmonary tuberculosis were 4.81 (95% CI 2.31-10.0) for patients co-morbid with splenectomy and any of the above diseases. Splenectomy is associated with a 1.9-fold increased risk of pulmonary tuberculosis in Taiwan. There is a synergistic effect between splenectomy and other co-morbidities on the risk of pulmonary tuberculosis.

Irritable bowel syndrome correlates with increased risk of Parkinson's disease in Taiwan

This study investigated whether an association exists between irritable bowel syndrome (IBS) and the risk of Parkinson's disease. This is a retrospective cohort study using the dataset of the Taiwan National Health Insurance Program from 2000 to 2010. We identified 23,875 patients (aged 20 years or older) with newly diagnosed IBS as the IBS group and 95,500 subjects without IBS as the non-IBS group for comparison. The main outcome was incident Parkinson's disease compared between both groups by the end of 2010. We measured the hazard ratio (HR) to evaluate the association between IBS and Parkinson's disease. The overall incidence of Parkinson's disease in the IBS group was 1.76-fold higher than that in the non-IBS group (16.4 vs. 9.33 per 10,000 person-years). The multivariable Cox proportional hazards regression analysis revealed that the adjusted HR of Parkinson's disease associated with IBS was 1.48 (95% CI 1.27, 1.72), compared with the non-IBS group. Age, women, hypertension, dementia, cerebrovascular disease and depression were also significantly associated with Parkinson's disease. Patients with irritable bowel syndrome are at an increased risk of developing Parkinson's disease. Further studies are required to explore the pathophysiological connection between these disorders.

Observational follow-up of the PROactive study: a 6-year update

AIMS

The PROactive study investigated pioglitazone for secondary prevention of macrovascular events in type 2 diabetes mellitus. Pioglitazone showed a 10% (non-significant) relative risk (RR) reduction for the primary composite endpoint and a significant 16% reduction for the main secondary endpoint (death, myocardial infarction, stroke) after a mean 34.5 months. There was no difference in cumulative malignancy incidence, but an imbalance in bladder malignancies (pioglitazone 14, placebo 5). We present a pre-specified 6-year interim analysis of a 10-year observational follow-up.

METHODS

Any patient completing PROactive was eligible. No study treatments were provided. A Cox proportional hazard model compared non-adjudicated macrovascular events (same endpoints as PROactive excluding acute coronary syndrome) based on original randomization. Malignancies were compared using conventional RR ratios.

RESULTS

Of 5238 randomized patients, 3599 (74%) entered the follow-up. For the follow-up (mean 5.8 years) or combined double-blind and follow-up periods (≤9.5 years, mean 8.7), there were no statistically significant differences in primary or main secondary endpoints. For the combined period, a similar percentage of patients had any diagnosed malignancy (RR = 1.05, 95% CI [0.89, 1.24]) or bladder malignancy (RR = 1.06, 95% CI [0.59, 1.89]) in the pioglitazone and placebo groups. There were fewer cases of bladder malignancy with pioglitazone (15 [0.6%] vs. 19 [0.7%] for placebo) for the combined period when events diagnosed in the first 365 days were excluded, and fewer cases for the follow-up period alone (10 [0.5%] vs. 17 [1.0%] for placebo). Further analyses of pioglitazone use (including use during follow-up) found no significant difference in bladder malignancies between any and no pioglitazone use for the combined period.

CONCLUSIONS

These data suggest that improved macrovascular outcomes seen with pioglitazone subside without continued pioglitazone treatment. The double-blind period bladder cancer imbalance did not persist in follow-up.

No Association between Depression and Risk of Hepatocellular Carcinoma in Older People in Taiwan

Objectives. The objective of this study was to determine whether there is a relationship between depression and risk of hepatocellular carcinoma (HCC) in older people in Taiwan. Methods. A case-control study was conducted to analyze the database from the Taiwan National Health Insurance program. We selected 1815 subjects aged 65 years or older with newly diagnosed HCC as the case group and 7260 subjects without HCC as the comparison group, from 2000 to 2010. Both groups were compared to measure the risk of HCC. Results. After controlling for confounders, the odds ratio of HCC was 0.81 in subjects with depression (95% confidence interval = 0.59, 1.11), as compared with nondepressed subjects. Conclusions. We conclude that no association is detected between depression and risk of hepatocellular carcinoma in older people in Taiwan.

NCOA5 haploinsufficiency results in glucose intolerance and subsequent hepatocellular carcinoma

Type 2 diabetes (T2D) and male gender are associated with hepatocellular carcinoma (HCC) development. We demonstrate that heterozygous deletion of the Ncoa5 gene causes spontaneous development of HCC exclusively in male mice. Tumor development is preceded by increased interleukin-6 (IL-6) expression, early-onset glucose intolerance, and progressive steatosis and dysplasia in livers. Blockading IL-6 overexpression averts glucose intolerance and partially deters HCC development. Moreover, reduced NCOA5 expression is associated with a fraction of human HCCs and HCCs with comorbid T2D. These findings suggest that NCOA5 is a haploinsufficient tumor suppressor and that NCOA5 deficiency increases susceptibility to both glucose intolerance and HCC, partially by increasing IL-6 expression. Thus, our findings open additional avenues for developing therapeutic approaches to combat these diseases.

Homeostasis model assessment of insulin resistance does not seem to predict response to telaprevir in chronic hepatitis C in the REALIZE trial

Baseline homeostasis model assessment-estimated insulin resistance (HOMA-IR), a marker for insulin resistance, has been associated with poor virologic response to peginterferon alpha/ribavirin (PR) in chronic hepatitis C. We evaluated the association between baseline HOMA-IR and pretreatment factors on sustained virologic response (SVR) to telaprevir (TVR) in genotype 1 patients with hepatitis C and prior peginterferon/ribavirin (PR) treatment failure. Patients were randomized to 12 weeks of TVR (750 mg q8h) plus peginterferon (180 μg/week) and ribavirin (1,000-1,200 mg/day) (with or without a 4-week lead-in) followed by PR, or PR alone (PR48), for 48 weeks. Univariate and multiple logistic regression analyses explored the prognostic significance of baseline HOMA-IR alone and adjusted for other pretreatment factors and SVR. The TVR arms were pooled for the purposes of this analysis. In all, 662 patients were randomized; 578 had baseline HOMA-IR and other prognostic data and were included in this analysis. Median baseline HOMA-IR was 2.6 (interquartile range [IQR] 1.7-4.3); 207 (36%), 206 (36%), and 165 (29%) patients had baseline HOMA-IR <2, 2 to <4, and ≥ 4, respectively. Male gender, higher body mass index, triglycerides, gamma-glutamyl transpeptidase, maximum alanine aminotransferase/aspartate aminotransferase, and fibrosis stage were associated with higher baseline HOMA-IR. Baseline HOMA-IR was associated with SVR in univariate analysis, but not after adjustment for other baseline prognostic factors (TVR: OR = 0.95, 95% confidence interval [CI]: 0.71,1.29; PR48: 0.60; 95% CI: 0.25,1.43).

CONCLUSION

In patients with prior PR treatment failure, baseline HOMA-IR correlated with SVR in univariate but not multivariate analyses, suggesting other factors have a more direct causal relationship with virologic response to TVR-based therapy than HOMA-IR.

Hepatocellular Carcinoma in Non-alcoholic Fatty Liver Disease: Epidemiology, Pathogenesis, and Prevention

Hepatocellular cancer (HCC) is the fifth most prevalent cancer worldwide and the third leading cause of cancer-related deaths. Non-alcoholic fatty liver disease (NAFLD), a spectrum of hepatic disorders associated with obesity and the metabolic syndrome, is a recognized risk factor for HCC. NAFLD that is advanced to cirrhosis carries the highest risk for HCC, but there is increasing concern that NAFLD-associated HCC may also occur in non-cirrhotic liver. As NAFLD is rapidly becoming the most common liver condition, it has been implicated in the worrisome trend of rising HCC incidence in a number of countries, which may offset successful measures in reducing the effect of virus-related liver cancer. Independently or in synergy with cirrhosis, NAFLD may provide a special oncogenic microenvironment through its pathogenic association with chronic nutrient excess and adipose tissue remodeling, characterized by pro-inflammatory adipokine profiles, lipotoxicity, altered hepatocellular bioenergetics, and insulin resistance. Better understanding of this complex process, and development of reliable biomarkers for HCC will be critical for early recognition and risk prediction. Moreover, correcting deranged lipid metabolism and restoring insulin sensitivity by lifestyle measures and targeted pharmacotherapy holds major promise for effective prevention of NAFLD-associated HCC.

Statin use and risk of liver cancer: A meta-analysis of 7 studies involving more than 4.7 million patients

AIM: To pool data currently available to determine the association between statin use and the risk of liver cancer.

METHODS: A computerized literature search was conducted to identify those relevant studies between January 1966 and March 2013. Stata 11.0 (Stata Corp, College Station, Texas) was used for statistical analyses. Pooled relative risk (RR) estimates with 95%CI were calculated for overall analysis and subgroup analyses, using the random- and fixed-effects models. Heterogeneities between studies were evaluated by Cochran’s Q test and I² statistic. The Begg’s funnel plot and Egger’s regression asymmetry test were used to detect the publication bias.

RESULTS: Seven studies were included in our meta-analysis according to the selection criteria, including four cohort studies and three case-control studies. These studies involved 4725593 people and 9785 liver cancer cases. The overall analysis showed that statin use was statistically associated with a significantly reduced risk of liver cancer (random-effects model, RR = 0.61, 95%CI: 0.49-0.76, P < 0.001; fixed-effects model, RR = 0.64, 95%CI: 0.57-0.71, P < 0.001); however, significant heterogeneity was found between studies (Cochran’s Q statistic = 19.13, P = 0.004; I² = 68.6%). All subgroup analyses provided supporting evidence for the results of overall analysis. Begg’s (Z = 0.15, P = 0.881) and Egger’s test (t =-0.44, P = 0.681) showed no significant risk of having a publication bias.

CONCLUSION: Statin use was associated with the reduced risk of liver cancer. To clearly clarify this relationship, more high quality studies are required.

NAFLD, NASH and liver cancer

NAFLD affects a large proportion of the US population and its incidence and prevalence are increasing to epidemic proportions around the world. As with other liver diseases that cause cirrhosis, NAFLD increases the risk of liver cancer, a disease with poor outcomes and limited therapeutic options. The incidences of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma are also rising, and HCC is now the leading cause of obesity-related cancer deaths in middle-aged men in the USA. In this Review, we summarize the correlations between liver cancer and NAFLD-related cirrhosis, and the role of the metabolic syndrome in the development of liver cancer from diverse aetiologies, including HCV-mediated cirrhosis. Recent advances in understanding the progression of NAFLD to HCC from preclinical models will also be discussed. Targeted genetic manipulation of certain metabolic or stress-response pathways, including one-carbon metabolism, NF-κB, PTEN and microRNAs, has been valuable in elucidating the pathways that regulate carcinogenesis in NAFLD. Although tremendous advances have occurred in the identification of diagnostic and therapeutic opportunities to reduce the progression of NAFLD, considerable gaps in our knowledge remain with regard to the mechanisms by which NAFLD and its risk factors promote liver cancer.

Two α-dicarbonyls downregulate migration, invasion, and adhesion of liver cancer cells in a p53-dependent manner

BACKGROUND

Hepatocellular carcinoma accounts for more than 600,000 deaths per year due to it being a highly invasive tumor. The α-dicarbonyl, methylglyoxal demonstrates efficacy at reducing tumor burden, however the anti-cancerous activities of 3-deoxyglucosone, have never been studied.

AIMS

To determine the anti-cancerous potential of methylglyoxal and 3-deoxyglucosone on liver tumor cells.

METHODS

The in vitro effects of methylglyoxal and 3-deoxyglucosone were studied by investigating migration, invasion, and adhesion of Huh-7, HepG2, and Hep3B cells.

RESULTS

3-Deoxyglucosone inhibited migration of Huh-7 and HepG2 cells. Methylglyoxal decreased migration of HepG2 cells. Additionally, 3-deoxyglucosone and methylglyoxal impaired invasion, and adhesion of Huh-7 and HepG2 cells. In Hep3B cells, a p53 null cell line, 3-deoxyglucosone and methylglyoxal had no effect on migration, invasion, or adhesion. However, both compounds inhibited invasion of wild-type p53 transfected Hep3B cells. Silencing of p53 in Huh-7 and HepG2 cells abrogated the effects of the α-dicarbonyls on cell invasion. 3DG and MG did not alter p53 total protein but promoted nuclear translocation of p53.

CONCLUSIONS

These studies suggest that 3-deoxyglucosone and methylglyoxal impair invasion, migration, and adhesion of hepatocellular carcinoma. The effects of both compounds on cell invasion are dependent on p53 and imply that α-dicarbonyls could be efficacious in the treatment of p53-expressing invasive liver tumors.

Diabetes and cancer: a 2013 synopsis

Diabetes, in particular type 2 diabetes, and cancer are two diseases that appear to be associated. Numerous epidemiological studies indicate indeed that diabetes increases the incidence of several tumors. Chronic hyperglycemia and/or insulin resistance with compensatory hyperinsulinemia could account for the association. On the other hand, the interpretation of the link between diabetes and cancer could be influenced by therapeutical interferences. Considering all these data together, cancer should be considered as a "new potential complication" of diabetes and integrated in the follow-up of diabetic subjects.

Non-viral causes of liver cancer: does obesity led inflammation play a role?

Liver cancer is the fifth most common cancer worldwide and the third most common cause of cancer mortality. Hepatocellular carcinoma (HCC) accounts for around 90% of primary liver cancers. Chronic infection with hepatitis B and hepatitis C viruses are two of most common causes of liver cancer. However, there are non-viral factors that are associated with liver cancer development. Numerous population studies have revealed strong links between obesity and the development of liver cancer. Obesity can alter hepatic pathology, metabolism and promote inflammation, leading to nonalcoholic fatty liver disease (NAFLD) and the progression to the more severe form, non-alcoholic steatohepatitis (NASH). NASH is characterised by prominent steatosis and inflammation, and can lead to HCC. Here, we discuss the role of obesity in inflammation and the principal signalling mechanisms involved in HCC formation.

Insulin resistance, steatosis and hepatitis C virus

Epidemiological studies have shown an increased occurrence of metabolic disorders such as insulin resistance (IR) and steatosis in patients with hepatitis C virus (HCV) infection. IR is believed to represent one of the central clinical features of the "metabolic syndrome" and the major pathogenetic factor for type 2 diabetes mellitus. In patients with chronic HCV hepatitis, IR may have several dangerous consequences such as accelerated progression of liver fibrosis, resistance to antiviral therapy and development of hepatocellular carcinoma. According to recent evidence, the global epidemic of metabolic disorders related to incorrect diets will lead physicians to deal with 1.2 billion patients with diabetes in the world in 2025. Given the high prevalence of HCV infection in several countries, metabolic manifestations will contribute to increasing morbidity and mortality in patients with HCV chronic infection in the near future. HCV treatment, shown able to decrease both the occurrence of HCV-related IR and diabetes, may reduce the risk of the associated morbidities.

Metformin therapy and risk of cancer in patients with type 2 diabetes: systematic review

Aims/Hypothesis

Diabetes treatments were related with either an increased or reduced risk of cancer. There is ongoing debate about a potential protective action of metformin. To summarize evidence on the association between metformin and risk of cancer and cancer mortality in patients with diabetes.

Methods

Data source: MEDLINE and EMBASE (January 1966-April 2012). We selected randomized studies comparing metformin and other hypoglycaemic agents and observational studies exploring the association between exposure to metformin and cancer. Outcomes were cancer mortality, all malignancies and site-specific cancers.

Results

Of 25307 citations identified, 12 randomized controlled trials (21,595 patients) and 41 observational studies (1,029,389 patients) met the inclusion criteria. In observational studies there was a significant association of exposure to metformin with the risk of cancer death [6 studies, 24,410 patients, OR:0.65, 95%CI: 0.53-0.80], all malignancies [18 studies, 561,836 patients, OR:0.73, 95%CI: 0.61-0.88], liver [8 studies, 312,742 patients, OR:0.34; 95%CI: 0.19-0.60] colorectal [12 studies, 871,365 patients, OR:0.83, 95%CI: 0.74–0.92], pancreas [9 studies, 847,248 patients, OR:0.56, 95%CI: 0.36–0.86], stomach [2 studies, 100701 patients, OR:0.83, 95%CI: 0.76–0.91], and esophagus cancer [2 studies, 100694 patients, OR:0.90, 95%CI: 0.83–0.98]. No significant difference of risk was observed in randomized trials. Metformin was not associated with the risk of: breast cancer, lung cancer, ovarian cancer, uterus cancer, prostate cancer, bladder cancer, kidney cancer, and melanoma.

Conclusions/Interpretation

Results suggest that Metformin might be associated with a significant reduction in the risk of cancer and cancer-related mortality. Randomized trials specifically designed to evaluate the efficacy of metformin as an anticancer agent are warranted.

Non-alcoholic fatty liver disease-related hepatocellular carcinoma: a sleeping tiger in the Asia Pacific

The epidemiology of hepatocellular carcinoma (HCC) in the Asia Pacific will undergo significant change over the next few decades as the prevalence of viral hepatitis declines and the burden of metabolic diseases increases. As the Asia Pacific embraces continued affluence, obesity and diabetes rates are burgeoning, becoming increasingly important to the incidence of HCC. Obesity and diabetes are established risk factors for HCC, either as substrates for non-alcoholic fatty liver disease (NAFLD) or as independent carcinogens themselves. This review summarises the epidemiological data on changing HCC trends in the Asia Pacific, particularly as it pertains to the emerging problem of NAFLD-related HCC.

Potential of incretin-based therapies for non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is becoming an epidemic, paralleling the increased prevalence of obesity and diabetes, which are risk factors. In this review, we present the current pre-clinical evidence showing that GLP-1 analogues and DPP4 inhibitors can improve hepatic steatosis. Although some of the effects could be due to overall improvement in metabolic parameters, there are data to support improvements independent of weight loss, as well as direct effects on the hepatocyte in vitro. Multiple hepatocyte signal transduction pathways appear to be activated by GLP-1 and its analogues, with both AMP-activated protein kinase and Akt proposed to be key players in improving hepatic steatosis. However, it is controversial as to whether the pancreatic-type GLP-1 receptor is present or responsible for conferring the GLP-1 signal in the hepatocyte. In total, the data support the need for more rigorous prospective clinical trials to further investigate the potential of incretin therapies for treatment of NAFLD.

Metformin and sulfonylureas in relation to cancer risk in type II diabetes patients: a meta-analysis using primary data of published studies

INTRODUCTION

Accumulating evidence suggests that patients with type 2 diabetes mellitus (T2DM) and hyperinsulinemia are at increased risk for developing malignancies. It remains to be fully elucidated whether use of metformin, an insulin sensitizer, and/or sulfonylureas, insulin secretagogues, affect cancer incidence in subjects with T2DM.

MATERIAL & METHODS

We performed a meta-analysis using PubMed, of randomized control trials (RCTs), cohorts, and case-control studies published through July 2012 that assess effects of metformin and/or sulfonylurea sulfonylureas on cancer risk at any site, in subjects with T2DM. Fixed and random effects meta-analysis models were used, and the effect size was summarized as relative risk (RR) for RCTs/cohorts and as odds ratio (OR) for the case-control studies.

RESULTS

Analysis of 24 metformin studies in subjects with T2DM showed that metformin use is associated with reduced risk for the development of cancer, in both cohort (RR=0.70 [95% CI=0.67-0.73]) and case-control studies (OR=0.90 [95% CI=0.84-0.98]), but this finding was not supported by RCTs (RR=1.01[95% CI=0.81-1.26]). Data from 18 sulfonylurea studies in subjects with T2DM showed that sulfonylurea use is associated with an increase in all-cancer risk, in cohort studies (RR=1.55 [95% CI=1.48 -1.63]), though data from RCTs (RR=1.17 [95% CI=0.95-1.45]) and case-control studies (OR=1.02 [95% CI=0.93-1.13]) failed to demonstrate a statistically significant effect.

CONCLUSIONS

This analysis using pooled primary data demonstrates that metformin use reduces, while sulfonylurea use may be associated with an increased cancer risk in subjects with T2DM. These findings need to be confirmed in large-scale RCTs before they are translated into clinical practice.