Augmentation effect of postprandial hyperinsulinaemia on growth of human hepatocellular carcinoma

Associations between serum glucose, insulin, insulin resistance and the risk of incident primary liver cancer or chronic liver disease mortality: a nested case-control study

BACKGROUND

To evaluate the associations between pre-diagnostic levels of serum insulin, glucose and insulin resistance (HOMA-IR) and future risk of incident primary liver cancer (PLC) or chronic liver disease (CLD)-related mortality.

METHODS

We used a nested case-control design to evaluate subjects over 22 years of follow-up. Glucose, insulin, and three markers of hepatitis B virus (HBV) and hepatitis C virus were measured in fasting baseline serum from 119 incident PLCs, 157 CLD-death cases and 512 matched controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression to estimate the associations between insulin, glucose, HOMA-IR and the risk of PLC or CLD death.

RESULTS

Compared with the lowest quartile of insulin, multivariable adjusted models showed that subjects in the highest quartile had elevated odds of developing PLC (OR_Q4/Q1 = 2.42, 95% CI = 1.26-4.75, P_trend = 0.007), particularly in HBV-positive subjects (P_interaction = 0.040), and of CLD death (OR_Q4/Q1 = 1.80, 95% CI = 1.02-3.21, P_trend = 0.018). For glucose, in the HBV-positive group, subjects in the fourth quartile had an increased risk of PLC (OR_Q4/Q1 = 2.18, 95% CI = 1.07-4.60, P_trend = 0.009), and of CLD mortality (OR_Q4/Q1 = 1.75, 95% CI = 0.95-3.28, P_trend = 0.019). Subjects with the highest HOMA-IR values had a threefold risk of developing PLC (OR_Q4/Q1 = 2.94, 95% CI = 1.54-5.87, P_trend = 0.001), and a twofold risk of CLD death (OR_Q4/Q1 = 2.20, 95% CI = 1.25-3.94, P_trend = 0.005).

CONCLUSIONS

We found that serum insulin and HOMA-IR could potentially be risk factors for PLC or CLD death.

Type 2 Diabetes Prevention Diet and Hepatocellular Carcinoma Risk in US Men and Women

OBJECTIVES

Adherence to a healthy diet has been associated with a reduced risk of type 2 diabetes (T2D). Hepatocellular carcinoma (HCC) may have overlapping mechanisms with T2D, such as inflammation and insulin resistance. Thus, we examined the association between a previously developed T2D prevention dietary pattern and HCC risk.

METHODS

We followed 87,943 women in the Nurses' Health Study and 49,665 men in the Health Professionals Follow-up Study for up to 32 years. The dietary diabetes risk reduction score, which includes dietary glycemic index, cereal fiber, ratio of polyunsaturated to saturated fats, trans fat, sugar-sweetened beverages, nuts, coffee, and red and processed meats, was obtained using validated food frequency questionnaires and updated every 4 years. The Cox proportional hazards regression model was used to calculate multivariable hazard ratios and confidence intervals (95% CIs).

RESULTS

During over 1.9 million person-years, a total of 160 incident HCC cases were identified. The dietary diabetes risk reduction score was associated with a lower risk of HCC (top vs bottom quartile; hazard ratio: 0.57, 95% CI: 0.34-0.95; Ptrend = 0.03). All the individual food and beverage items were associated with the risk of HCC in the expected direction, although the association was weaker than the overall dietary pattern.

DISCUSSION

Greater adherence to the T2D prevention diet was associated with a lower risk of developing HCC among US men and women. Further studies are needed to confirm and extend our findings.

Liver stiffness measured by transient elastography as predictor of prognoses following portosystemic shunt occlusion

BACKGROUND AND AIM

This study aimed to identify predictors of model for end-stage liver disease sodium score reductions and improvements in vital prognoses following portosystemic shunt occlusion in portal hypertension patients.

METHODS

Seventy cirrhotic patients with major portosystemic shunts and a mean model for end-stage liver disease sodium score of 10.5 underwent balloon-occluded retrograde transvenous obliteration between February 2008 and March 2017. We calculated the scores before and 1 month after shunt occlusion. The long-term outcomes were monitored, and vital prognoses were analyzed.

RESULTS

The model for end-stage liver disease sodium score did not change significantly 1 month post-balloon-occluded retrograde transvenous obliteration, and the score decreased postoperatively in 31 (44.3%) patients. Univariate analyses showed that decline in the score after portosystemic shunt occlusion was strongly associated with hepatic encephalopathy as a procedural indication, lower liver volumes, and lower liver stiffness levels measured by transient elastography before treatment (P < 0.05). Multivariate logistic regression analysis identified preoperative liver stiffness level as an independent predictor of model for end-stage liver disease sodium score amelioration following balloon-occluded retrograde transvenous obliteration (P < 0.05), and receiver operating characteristic curve analysis determined a liver stiffness cutoff value of 21.6 kPa, with a sensitivity of 76.0% and specificity of 69.6%. The Kaplan-Meier method determined that overall survival rates after treatment in patients with liver stiffness < 21.6 kPa were significantly higher than in patients with liver stiffness ≥ 21.6 kPa (P < 0.05).

CONCLUSIONS

Liver stiffness measured by transient elastography may predict improvements in model for end-stage liver disease sodium scores and in survival rates after portosystemic shunt occlusion in portal hypertension patients.

A randomized placebo-controlled trial of prophylactic dexamethasone for transcatheter arterial chemoembolization

This randomized, double-blind, placebo-controlled trial evaluated dexamethasone efficacy at preventing fever, anorexia, and nausea/vomiting, the most frequent adverse events of transcatheter arterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC). Child-Pugh class A/B patients with HCC and no macrovascular invasion/extrahepatic metastases were randomly assigned to either a dexamethasone regimen (day 1, intravenous dexamethasone [20 mg] and granisetron [3 mg] before TACE; days 2 and 3, intravenous dexamethasone [8 mg]) or a control regimen (day 1, intravenous placebo [saline] and granisetron [3 mg]; days 2 and 3, intravenous placebo). The primary endpoint was complete response, defined as the absence of grade ≥1 fever, anorexia, or nausea/vomiting according to the Common Terminology Criteria for Adverse Events (version 4.0) and no use of rescue therapy for 120 hours after TACE. A total of 120 patients between October 2010 and June 2013 were randomly assigned to treatment groups. Overall the complete response rate was greater with the dexamethasone regimen than with the control regimen (47.5%, 95% confidence interval 34.3%-60.9%, versus 10.2%, 95% confidence interval 3.8%-20.8%; P < 0.001). Cumulative incidences of fever, anorexia, and nausea/vomiting were higher in the control regimen group compared with the dexamethasone group (P < 0.001, P < 0.001, and P = 0.095, respectively). The dexamethasone regimen was generally well tolerated by HCC patients including those with well-controlled diabetes mellitus and those with hepatitis B virus infection. Conclusion: The dexamethasone regimen was more effective than the control regimen at preventing TACE-induced fever, anorexia, and nausea/vomiting in patients with HCC. (Hepatology 2018;67:575-585).

Higher Glucose and Insulin Levels Are Associated with Risk of Liver Cancer and Chronic Liver Disease Mortality among Men without a History of Diabetes

Insulin resistance likely increases the risk of chronic liver disease (CLD) and liver cancer, but long-term prospective studies with measured fasting glucose and insulin are lacking. We evaluated the associations of prediagnostic fasting glucose, insulin, and the homeostasis model assessment of insulin resistance (HOMA-IR) with liver cancer and CLD mortality in a prospective study of Finnish male smokers with extended follow-up time (≤22 years) and information on known risk factors using data from 138 incident primary liver cancer cases, 216 CLD deaths, and 681 matched controls. Fasting glucose and insulin were measured in baseline serum. We used unconditional logistic regression to estimate ORs and 95% confidence intervals adjusted for age, alcohol, education, smoking, body mass index, and hepatitis B and C viral status. Among those without self-reported diabetes, glucose was positively associated with liver cancer [quartile 3 vs. quartile 1 (Q3/Q1): OR = 1.88; 1.03-3.49; Q4/Q1: OR = 2.40; 1.33-4.35; P_trend = 0.002], and undiagnosed, biochemically defined, diabetes was associated with higher risk of liver cancer (OR = 2.95; 1.46-5.96) and CLD mortality (OR = 1.88; 1.00-3.56). Serum insulin and HOMA-IR were also positively associated with liver cancer (Q4/Q1: OR = 3.41; 1.74-6.66; P_trend < 0.0001; OR = 3.72; 1.89-7.32, P_trend < 0.0001, respectively) and CLD (OR = 2.51; 1.44-4.37; P_trend = 0.0002; OR = 2.31; 1.34-3.97; P_trend = 0.001, respectively), with stronger associations observed for liver cancer diagnosed >10 years after baseline. In conclusion, elevated fasting glucose and insulin and insulin resistance were independently associated with risk of liver cancer and CLD mortality, suggesting a potentially important etiologic role for insulin and glucose dysregulation even in the absence of diagnosed diabetes. Cancer Prev Res; 9(11); 866-74. ©2016 AACR.

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

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

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.

Occlusion of portosystemic shunts improves hyperinsulinemia due to insulin resistance in cirrhotic patients with portal hypertension

BACKGROUND

Liver cirrhosis (LC) is often complicated by hyperinsulinemia due to insulin resistance (IR), which is considered to be closely related to shunt formation and impaired liver function. This study evaluates whether balloon-occluded retrograde transvenous obliteration (B-RTO) can affect glucose and insulin metabolism in patients with LC.

METHODS

Twenty-five cirrhotic patients (mean age = 69.6 years; female/male = 12/13; hepatitis C virus/alcohol/nonalcoholic steatohepatitis = 14/6/5; Child-Pugh's class A/B = 10/15) with gastric varices and/or hepatic encephalopathy caused by portosystemic shunts (PSS) due to portal hypertension (PH) underwent B-RTO at our hospital. Testing was performed before and at 1 month after the procedure.

RESULTS

Shunt occlusion resulted in a decrease in extrahepatic collateral blood flow and an increase in portal venous flow, as well as a dramatic improvement in hepatic function markers. In addition, B-RTO significantly decreased homeostasis model assessment (HOMA) of IR without a statistical decline of HOMA of β-cell function. The 75-g oral glucose tolerance test (75-OGTT) revealed that occlusion of PSS reduced both fasting immunoreactive insulin (IRI) levels and the area under the curve for IRI. However, no significant change in preprandial or postprandial plasma glucose levels was observed. Furthermore, according to the criteria of the American Diabetes Association, B-RTO led to an improved 75-OGTT profile in 58.3 % of patients who had impaired glucose tolerance or diabetes mellitus before the procedure.

CONCLUSIONS

Shunt occlusion improves IR-related hyperinsulinemia through increased portal venous flow, ameliorated liver function, and consequent augmented hepatic insulin clearance in cirrhotic patients with PH.

Prospective evaluation of type 2 diabetes mellitus on the risk of primary liver cancer in Chinese men and women

BACKGROUND

No prospective study has investigated the relationship between type 2 diabetes mellitus (T2DM) and the risk of primary liver cancer (PLC) in mainland China, and little is known about the effect of diabetes duration on PLC risk.

DESIGN

Data from two population-based cohorts (the Shanghai Men's Health Study, SMHS, 2002-2006 and the Shanghai Women's Health Study, SWHS, 1996-2000) were thus used to assess the associations among T2DM, diabetes duration and PLC risk in Chinese population.

RESULTS

During follow-up through 2009, 344 incident PLC cases were identified among 60 183 men and 73 105 women. T2DM is significantly associated with the increased risk of PLC in both men [hazard ratio (HR) = 1.63, 95% confidence interval (CI) 1.06-2.51] and women (HR = 1.64, 95% CI 1.03-2.61). The highest risk of incident liver cancer was observed in the first 5 years after diabetes diagnosis, and decreased substantially with the prolonged diabetes duration (P(trend) < 0.001). No synergistic interaction in the development of PLC was found between diabetes and other known risk factors.

CONCLUSIONS

T2DM is associated with the increased risk of subsequent liver cancer within 5 years after diagnosis in Chinese population, suggesting that hyperinsulinaemia rather than hyperglycaemia is more likely to be a primary mediator for this association.

Decreased expression of insulin and increased expression of pancreatic transcription factor PDX-1 in islets in patients with liver cirrhosis: a comparative investigation using human autopsy specimens

BACKGROUND

Glucose intolerance in patients with liver cirrhosis (LC), known as hepatogenous diabetes, is thought to be distinct from type 2 diabetes (T2DM) in some aspects. Hyperinsulinemia and/or insulin resistance in liver disease is associated with hepatocarcinogenesis, growth of hepatocellular carcinoma, and poor prognosis. However, the pathophysiological processes in islets that are responsible for hyperinsulinemia in LC are still not precisely known. Therefore, we investigated the histopathological differences in islets of Langerhans cells between LC and T2DM.

METHODS

A total of 35 human autopsy pancreatic tissue samples were used in this study (control, n = 18; T2DM, n = 6; LC, n = 11). The expression of insulin, glucagon, somatostatin, pancreatic duodenal homeobox-1 (PDX-1), proliferating cell nuclear antigen (PCNA), and Ki-67 was examined using immunohistochemistry and quantitated by image analysis.

RESULTS

Islet hypertrophy and a significant increase in PCNA-positive cells in islets were observed in the tissues from LC cases. The insulin-positive areas in islets were significantly decreased in LC cases compared with control and T2DM cases (P = 0.001, P = 0.035, respectively), whereas the PDX-1-positive area was significantly increased in LC cases (P = 0.001) compared with the control. Furthermore, disorganization of pancreatic endocrine cells and nucleocytoplasmic translocation of PDX-1 were both seen in the LC subjects.

CONCLUSIONS

In LC, islets undergo hypertrophy and exhibit paradoxical expression of insulin and PDX-1. In the subjects autopsied, insulin expression was decreased, whereas expression of the pancreatic transcription factor PDX-1 was increased in LC. These results point to important distinctions between LC and T2DM.

Liver and diabetes. A vicious circle

The complex and bi-directional relationship linking the liver and diabetes has recently gained intense new interest. This critical review of the published work aims to highlight the most recent basic and clinical data underlying the development of type 2 diabetes, in those with non-alcoholic fatty liver disease. Moreover, the potentially detrimental effects of type 2 diabetes in liver injury are also discussed in each of the two sections of the present paper. Fatty liver and diabetes share insulin resistance as their chief pathogenic determinant. The roles of the hypothalamus, the intestinal microbiome, white adipose tissue and inflammation are discussed in detail. Molecular insights into hepatocyte insulin resistance as the initiator of systemic insulin resistance are also presented with full coverage of the danger of fatty acids. Lipotoxicity, apoptosis, lipoautophagy, endoplasmic reticular stress response and recent developments in genetics are discussed. Closing the circle, special emphasis is given to biochemical pathways and clinical evidence supporting the role of type 2 diabetes as a risk factor for the development of progressive liver disease, including non-alcoholic steatohepatitis, cirrhosis and primary liver cancer. In conclusion, data support non-alcoholic fatty liver disease as a risk factor for the development of type 2 diabetes which is, in turn, a major contributor to progressive liver disease. This pathway leading from fatty liver to type 2 diabetes and back from the latter to the progressive liver disease is a vicious circle.

Evaluation of a novel non-invasive (13) C-glucose breath test for the identification of diabetes mellitus in cirrhotic patients

AIM

  Diabetes mellitus (DM) has been reported to worsen the long-term prognosis of cirrhotic patients, and many studies have reported that DM is an independent risk factor for hepatocellular carcinoma. However, an accurate diagnosis of DM is sometimes difficult in cirrhotic patients. Recently, a novel non-invasive (13) C-glucose breath test has been reported to be useful for diagnosing insulin resistance in non-cirrhotic patients. The aim of this study was to evaluate the efficacy of this tool for the identification of DM in cirrhotic patients.

METHODS

  Thirty eight cirrhotic patients with normal fasting serum glucose and hemoglobin A1c levels underwent the (13) C-glucose breath test and the oral glucose tolerance test. Blood and breath samples were collected at baseline and at 30, 60 and 120 min after ingestion of 100 mg (13) C-labeled glucose and 75 g glucose.

RESULTS

  There was a strong correlation between the change in the concentrations at 2 h for the measured (13) C-glucose breath test (2h-BT) and the 2 h plasma glucose level (r = -0.60, P < 0.0001). In a receiver-operator curve analysis using the 2h-BT, the area under the curve was determined to be 0.88, with a sensitivity and specificity (cut-off value of 3.5‰) of 82% and 85%, respectively, for the detection of DM. Multivariate analysis showed the 2h-BT to be an independent parameter to identify DM.

CONCLUSION

  The (13) C-glucose breath test is a useful tool and has the potential to become a routine outpatient examination for the screening of DM in cirrhotic patients.

Resection of nonalcoholic steatohepatitis-associated hepatocellular carcinoma: a Western experience

Introduction. Hepatocellular carcinoma is now known to arise in association with nonalcoholic steatohepatitis. The aim of this study is to examine the clinicopathological features of this entity using liver resection cases at a large Western center. Methods. We retrospectively reviewed all cases of partial liver resection for hepatocellular carcinoma over a 10-year period. We included for the purpose of this study patients with histological evidence of nonalcoholic steatohepatitis and excluded patients with other chronic liver diseases such as viral hepatitis and alcoholic liver disease. Results. We identified 9 cases in which malignancy developed against a parenchymal background of histologically-active nonalcoholic steatohepatitis. The median age at diagnosis was 58 (52-82) years, and 8 of the patients were male. Median body mass index was 30.2 (22.7-39.4) kg/m(2). Hypertension was present in 77.8% of the patients and diabetes mellitus, obesity, and hyperlipidemia in 66.7%, respectively. The background liver parenchyma was noncirrhotic in 44% of the cases. Average tumor diameter was 7.0 ± 4.8 cm. Three-fourths of the patients developed recurrence within two years of resection, and 5-year survival was 44%. Conclusion. Hepatocellular carcinoma may arise in the context of nonalcoholic steatohepatitis, often before cirrhosis has developed. Locally advanced tumors are typical, and long-term failure rate following resection is high.

[Obesity and gastrointestinal cancer-related factor]

Despite a higher incidence and less favorable outcome of malignant tumors in obese patients, much less recognized is the link between obesity and cancer. The mechanism of the association of obesity with carcinogenesis remains incompletely understood. Postulated mechanisms include insulin resistance, insulin-like growth factor signaling, chronic inflammation, immunomodulation, hyperglycemia-induced oxidative stress, and changes of intestinal microbiome. Insulin resistance leads to direct mitogenic and antiapoptotic signaling by insulin and the insulin-like growth factor axis. Obesity can be considered to be a state of chronic low-grade inflammation. In obesity, numerous proinflammatory cytokines are released from adipose tissue which may involve in carcinogenesis. Hyperglycemia in susceptible cells results in the overproduction of superoxide and this process is the key to initiating all damaging pathways related to diabetes. This hyperglycemia-induced oxidative stress could be one possible link among obesity, diabetes, and cancer development. The role of obesity-related changes in the intestinal microbiome in gastrointestinal carcinogenesis deserves further attention.

Chronic hepatitis c genotype-4 infection: role of insulin resistance in hepatocellular carcinoma

Background

Hepatitis C virus (HCV) is a major cause of chronic hepatitis and hepatocellular carcinoma (HCC) and different HCV genotypes show characteristic variations in their pathological properties. Insulin resistance (IR) occurs early in HCV infection and may synergize with viral hepatitis in HCC development. Egypt has the highest reported rates of HCV infection (predominantly genotype 4) in the world; this study investigated effects of HCV genotype-4 (HCV-4) on prevalence of insulin resistance in chronic hepatitis C (CHC) and HCC in Egyptian patients.

Methods

Fifty CHC patients, 50 HCC patients and 20 normal subjects were studied. IR was estimated using HOMA-IR index and HCV-4 load determined using real-time polymerase chain reaction. Hepatitis B virus was excluded by enzyme-linked immunosorbent assay. Standard laboratory and histopathological investigations were undertaken to characterize liver function and for grading and staging of CHC; HCC staging was undertaken using intraoperative samples.

Results

HCC patients showed higher IR frequency but without significant difference from CHC (52% vs 40%, p = 0.23). Multivariate logistic regression analysis showed HOMA-IR index and International Normalization Ratio independently associated with fibrosis in CHC; in HCC, HbA1c, cholesterol and bilirubin were independently associated with fibrosis. Fasting insulin and cholesterol levels were independently associated with obesity in both CHC and HCC groups. Moderate and high viral load was associated with high HOMA-IR in CHC and HCC (p < 0.001).

Conclusions

IR is induced by HCV-4 irrespective of severity of liver disease. IR starts early in infection and facilitates progression of hepatic fibrosis and HCC development.

Use of HOMA-IR in hepatitis C

Chronic infection with hepatitis C virus (HCV) can induce insulin resistance (IR) in a genotype-dependent manner and contributes to steatosis, progression of fibrosis and resistance to interferon plus ribavirin therapy. Our understanding of HCV-induced IR has improved considerably over the years, but certain aspects concerning its evaluation still remain elusive to clinical researchers. One of the most important issues is elucidating the ideal method for assessment of IR in the setting of hepatitis C. The hyperinsulinaemic euglycaemic clamp is the gold standard method for determining insulin sensitivity, but is impractical as it is labour intensive and time-consuming. To date, all human studies except for four where IR was evaluated in the HCV setting, an estimation of IR has been used rather than direct measurements of insulin-mediated glucose uptake. The most commonly used estimation in the HCV population is the homeostasis model assessment of insulin resistance (HOMA-IR) which is calculated from a single measurement of fasting insulin and glucose. In this article, we review the use and reporting of HOMA in the literature and provide guidance on its appropriate as well as inappropriate use in the hepatitis setting.

Prognostic role of diabetes mellitus in hepatocellular carcinoma patients after curative treatments: a meta-analysis

BACKGROUND

The prognostic role of diabetes mellitus (DM) coexisting with hepatocellular carcinoma (HCC) remains controversial. To clarify its impact on survival in HCC patients after curative treatments, a meta-analysis was performed.

DATA SOURCES

Eligible studies were identified through multiple search strategies in the databases PubMed (MEDLINE), EMBASE, the Cochrane Library and ACP Journal Club between January 1950 and March 2010. Ten studies fulfilled the inclusion criteria, and data were aggregated comparing overall survival and recurrence-free survival in HCC patients according to DM status.

RESULTS

The pooled hazard ratios (HRs) estimate for overall survival was 1.34 (95% CI, 1.18-1.51; P<0.0001) and for recurrence-free survival was 1.48 (95% CI, 1.00-2.18; P<0.0001), showing a worse survival for HCC with coexisting DM. However, the patients with DM had a shorter survival time in HCV-related HCC (HR=1.71; 95% CI, 1.10-2.66; P=0.016), while HBV-related cases were not significantly different (HR=1.29; 95% CI, 0.69-2.40; P=0.182). Meanwhile, the coexistence of DM impaired overall survival in HCC patients with a small tumor burden (HR=1.63; 95% CI, 1.25-2.12; P<0.0001).

CONCLUSION

HCC patients with coexisting DM have a shorter survival time and a higher risk for tumor recurrence after curative treatments, while the precise value should be defined in more clinical trials with consistent methodology, especially prospective studies.

Small molecule inhibitors of the IGF-1R/IR axis for the treatment of cancer

INTRODUCTION

The IGF-1 receptor (IGF-1R) is a receptor tyrosine kinase and is well established as a key regulator of tumor cell growth and survival. There is also a growing body of data to support a role for the structurally and functionally related insulin receptor (IR) in human cancer. Bidirectional crosstalk between IGF-1R and IR is observed, where specific inhibition of either receptor confers a compensatory increase in the activity for the reciprocal receptor, therefore dual inhibition of both IGF-1R and IR may be important for optimal efficacy. The importance of IGF-1R and IR as targets in cancer is further underscored by their contribution to resistance against both cytotoxic and molecularly targeted anti-cancer therapeutics. Currently, both IGF-1R-neutralizing antibodies and small-molecule tyrosine kinase inhibitors of IGF-1R/IR are in clinical development.

AREAS COVERED

The importance of IGF-1R and IR as cancer targets and how IGF-1R/IR inhibitors may sensitize tumor cells to the anti-proliferative and pro-apoptotic effects of other anti-tumor agents. The potential advantages of small molecule IGF-1R/IR inhibitors compared with IGF-1R-specific neutralizing antibodies, and the characteristics of small-molecule IGF-1R inhibitors that have entered clinical development.

EXPERT OPINION

Because of compensatory crosstalk between IGF-1R and IR, dual IGF-1R and IR tyrosine kinase inhibitors may have superior anti-tumor activity compared to anti-IGF-1R specific antibodies. The clinical success for IGF-1R/IR inhibitors may ultimately be dependent upon our ability to correctly administer these agents to the right niche patient subpopulation using single agent therapy, when appropriate, or using the right combination therapy.

Obesity, type 2 diabetes and risk of digestive cancer

The frequency of obesity has been increasing worldwide for 20 years. Many epidemiological studies support a correlation between obesity and increased risk of cancer, particularly digestive cancers in both genders, and gynaecological cancer in women. Currently, about 5% of cancers could be directly related to overweight. Carcinogenesis mechanisms induced by obesity involve insulin resistance, adipokine and angiogenic factor secretions, and inflammation. Experimental and clinical evidence suggest that insulin resistance plays a major role in carcinogenesis. Insulin and non-protein banded IGF-1, whose levels are increased in type 2 diabetes, stimulate cellular growth and inhibit apoptosis. Abnormalities in adipokine secretion by the central adipose tissue play a role at different stages of obesity-induced carcinogenesis. Excess of leptin and PAI-1, associated with a decrease in adiponectin secretion in obese people, contributes to carcinogenesis through cellular growth and angiogenesis stimulation. Remodelling of the extracellular matrix due to metalloproteinase stimulation by PAI-1 is also able to promote cell migration. Obesity not only increases cancer frequency, but is also liable to modify the prognosis and the response to antiangiogenic therapy of digestive cancers. This data suggests the need for clinicians to take into account overweight in cancer risk evaluation and to consider obesity and metabolic disorders as confounding factors in designing therapeutic studies.

Effects of late evening snack on diurnal plasma glucose profile in patients with chronic viral liver disease

AIM

  Glycemic control is important to improve the prognosis in cirrhotic patients with complications from diabetes. A late evening snack (LES) has been recommended for cirrhotic patients. We investigated the effects of LES on diurnal plasma glucose levels.

METHODS

  Subjects comprised 47 patients with chronic viral liver disease (chronic hepatitis, n = 11; cirrhosis, n = 36) treated in the Department of Gastroenterology & Hepatology, Dokkyo Medical University Koshigaya Hospital. Diurnal variations in plasma glucose were first investigated with three meals/day, in accordance with the European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines. Starting the next day, patients were given four meals including a LES, without changing meal content. Diurnal variations in plasma glucose were examined on day 7, and urine C-peptide immunoreactivity (CPR), and homeostasis model assessment insulin resistance (HOMA-IR) were investigated.

RESULTS

  With a LES, plasma glucose levels in patients with chronic hepatitis were significantly lower 2 hours before and 2 hours after dinner. In cirrhotic patients, significant decreases in plasma glucose levels were seen 2 hours after breakfast, before lunch, and before dinner. Significant decreases were noted in average plasma glucose levels and highest plasma glucose levels with four meals including a LES in patients with liver cirrhosis. This decrease was greater when maximum plasma glucose levels were higher on the three-meal regimen.

CONCLUSIONS

  Improvements in plasma glucose levels were seen with four meals per day, including a LES, in viral chronic liver disease, particularly cirrhosis.

Adipocytokine involvement in hepatocellular carcinoma after sustained response to interferon for chronic hepatitis C

AIM

  Interferon (IFN) dramatically reduces the risk of hepatocellular carcinoma (HCC) after a sustained virological response (SVR) to chronic hepatitis C (CH-C). However, HCC still develops in some patients after SVR. To evaluate metabolic factors in patients with HCC occurring after SVR and to determine whether insulin resistance and adipocytokines were involved in this etiology.

METHODS

  We examined clinical and biochemical features, histological findings and serum levels of adipocytokine prior to IFN therapy and at the detection of HCC in nine patients who were diagnosed with HCC. As controls, 27 patients were included who showed SVR but had not been diagnosed with HCC for at least 5 years after SVR.

RESULTS

  Three of four patients who developed HCC within 5 years after SVR showed liver cirrhosis when HCC was diagnosed. Prior to IFN therapy, four of nine HCC patients were diagnosed as having type 2 diabetes mellitus. Serum levels of leptin and insulin, Homeostatic Model of Assessment of Insulin Resistance and body mass index (BMI) were significantly higher and serum adiponectin was significantly lower in HCC patients at the time of HCC detection than in control patients more than 5 years after SVR. Six HCC patients had increased BMI and one HCC patient had a decreased BMI during the observation period.

CONCLUSION

  Hepatic fibrosis may be tightly related to the emergence of HCC after SVR. Insulin resistance and adipocytokine disorders may be implicated in hepatocarcinogenesis after SVR, in part by promoting hepatic fibrosis.

Importance of hepatitis C virus-associated insulin resistance: Therapeutic strategies for insulin sensitization

Insulin resistance is one of the pathological features in patients with hepatitis C virus (HCV) infection. Generally, persistence of insulin resistance leads to an increase in the risk of life-threatening complications such as cardiovascular diseases. However, these complications are not major causes of death in patients with HCV-associated insulin resistance. Indeed, insulin resistance plays a crucial role in the development of various complications and events associated with HCV infection. Mounting evidence indicates that HCV-associated insulin resistance may cause (1) hepatic steatosis; (2) resistance to anti-viral treatment; (3) hepatic fibrosis and esophageal varices; (4) hepatocarcinogenesis and proliferation of hepatocellular carcinoma; and (5) extrahepatic manifestations. Thus, HCV-associated insulin resistance is a therapeutic target at any stage of HCV infection. Although the risk of insulin resistance in HCV-infected patients has been documented, therapeutic guidelines for preventing the distinctive complications of HCV-associated insulin resistance have not yet been established. In addition, mechanisms for the development of HCV-associated insulin resistance differ from lifestyle-associated insulin resistance. In order to ameliorate HCV-associated insulin resistance and its complications, the efficacy of the following interventions is discussed: a late evening snack, coffee consumption, dietary iron restriction, phlebotomy, and zinc supplements. Little is known regarding the effect of anti-diabetic agents on HCV infection, however, a possible association between use of exogenous insulin or a sulfonylurea agent and the development of HCC has recently been reported. On the other hand, insulin-sensitizing agents are reported to improve sustained virologic response rates. In this review, we summarize distinctive complications of, and therapeutic strategies for, HCV-associated insulin resistance. Furthermore, we discuss supplementation with branched-chain amino acids as a unique insulin-sensitizing strategy for patients with HCV-associated insulin resistance.

Association of exogenous insulin or sulphonylurea treatment with an increased incidence of hepatoma in patients with hepatitis C virus infection

BACKGROUND

Diabetes mellitus is frequently seen in hepatitis C patients and is often treated with antidiabetic agents that increase serum insulin levels. Because insulin is a growth-promoting hormone, antidiabetic agents could pose a risk for hepatocellular carcinoma (HCC).

AIM

The aim of this study was to investigate an association between antidiabetic therapies and the incidence of HCC in hepatitis C patients with diabetes mellitus.

METHODS

A nested case-control study was conducted. Participants were recruited from a cohort study, in which patients with hepatitis C were consecutively registered. Participants were assigned to an HCC group (n=138) or a non-HCC group (n=103). To identify independent factors, variables including use of antidiabetic agents were analysed by logistic regression analysis.

RESULTS

Besides ageing, being male, cirrhosis and hypoalbuminaemia, use of exogenous insulin and a second-generation sulphonylurea were significant independent factors associated with an incidence of HCC [odds ratio (OR) 2.969, 95% confidence interval (CI) 1.293-6.819, P<0.0103 and OR 6.831, 95% CI 1.954-23.881, P<0.0026 respectively). In stratified analyses, the impact of these antidiabetic agents was more evident in patients who were non-cirrhotic than in those who were cirrhotic.

CONCLUSIONS

Exogenous insulin and a second-generation sulphonylurea were independent variables associated with an incidence of HCC in hepatitis C patients with diabetes mellitus. This association was evident in patients who were non-cirrhotic. To verify a causal relationship between these antidiabetic agents and the development of HCC, a prospective cohort study is required.

Hepatitis C and diabetes: one treatment for two diseases?

Abstract Epidemiological data clearly indicate a link between chronic hepatitis C (CHC) and disturbed glucose homeostasis. The prevalences of both type 2 diabetes mellitus (T2DM) and insulin resistance (IR) are higher among those chronically infected with hepatitis C when compared with the general population and those with other causes of chronic liver disease. Both IR and diabetes are associated with adverse outcomes across all stages of CHC including the liver transplant population. The adverse effects that directly influence patient outcome are reduced responsiveness to antiviral therapy, more rapid progression of fibrosis to cirrhosis and a higher incidence of hepatocellular carcinoma. Although both viral and host factors are known to contribute to IR (and therefore the risk of T2DM), there is a paucity of evidence to support interventions targeting IR with pharmacotherapy or lifestyle intervention. The purpose of this review is to examine the impact of abnormalities of glucose homeostasis in CHC, and in so doing, to raise a number of questions. How do we identify those at risk of diabetes in CHC? Can we reduce the incidence of hepatoma and reduce transplant-related morbidity and mortality by preventing or treating diabetes? Can we improve the response to antiviral therapy by pretreating IR and T2DM in treatment candidates? Ultimately, can we cure two diseases, diabetes and CHC, with one treatment?

Diabetes pattern on the 75 g oral glucose tolerance test is a risk factor for hepatocellular carcinoma in patients with hepatitis C virus

BACKGROUND

Patients with hepatitis C virus (HCV) frequently show glucose intolerance. Diabetes mellitus (DM) has been proposed to be a risk factor for hepatocellular carcinoma (HCC).

AIMS

The aim of this study is to clarify the influence of glucose intolerance as evaluated by the 75 g oral glucose tolerance test (OGTT) on hepatocarcinogenesis in patients with HCV.

METHODS

This study was carried out in a cohort of 197 patients with HCV who had not been previously diagnosed as having DM. All patients underwent the 75 g OGTT at entry. They were also screened for HCC and, thereafter, the rate of hepatocarcinogenesis was compared between the patients with and without glucose intolerance.

RESULTS

Based on the results of the 75 g OGTT, 125 (63%) had normal glucose tolerance (NGT), 49 (25%) had impaired glucose tolerance (IGT) and 23 (12%) had the DM pattern. HCC occurred more frequently in patients with the DM pattern than in patients with either NGT or IGT. Even in patients without advanced liver fibrosis, HCC was more frequently observed in patients with DM than in patients with NGT. A multiple logistic regression analysis showed advanced liver fibrosis, the DM pattern on the 75 g OGTT, an older age and gamma-glutamyltransferase to all be independent risk factors related to hepatocarcinogenesis.

CONCLUSIONS

A DM pattern on the 75 g OGTT was thus found to be associated with hepatocarcinogenesis and the 75 g OGTT is considered to be useful for identifying this risk factor for HCC in patients with HCV.

Insulin resistance, serum adipokines and risk of fibrosis progression in patients transplanted for hepatitis C

In the nontransplant setting diabetes mellitus is a risk factor for disease progression in patients with chronic hepatitis C virus (HCV) infection. The impact of early insulin resistance on the development of advanced fibrosis, even in the absence of clinically apparent diabetes mellitus, is not known. Our aim was to determine whether the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) can be used to identify insulin-resistant patients at risk for rapid fibrosis progression. Cohort study including patients transplanted for chronic HCV between January 1, 1995 and January 1, 2005. One hundred sixty patients were included; 25 patients (16%) were treated for diabetes mellitus and 36 patients (23%) were prediabetic, defined as HOMA-IR >2.5. Multivariate Cox regression analysis showed that insulin resistance (hazard ratio (HR) 2.07; confidence interval (CI) 1.10-3.91, p = 0.024), donor age (HR 1.33;CI 1.08-1.63, p = 0.007) and aspartate aminotransferase (HR 1.03;CI 1.01-1.05, p < 0.001) were significantly associated with a higher probability of developing advanced fibrosis, i.e. Knodell fibrosis stage 3 or 4, whereas steatosis (HR 0.94;CI 0.46-1.92, p = 0.87) and acute cellular rejection (HR 1.72;CI 0.88-3.36, p = 0.111) were not. In conclusion, posttransplant insulin resistance is strongly associated with more severe recurrence of HCV infection. HOMA-IR is an important tool for the identification of insulin resistance among patients at risk for rapid fibrosis progression after liver transplantation for HCV.

Effects of a late evening snack combined with alpha-glucosidase inhibitor on liver cirrhosis

AIM

A late evening snack (LES) is recommended for protein-energy malnutrition in patients with liver cirrhosis. However, many cases of liver cirrhosis have accompanying impaired glucose tolerance and there are concerns that LESs might aggravate glucose intolerance. In this study, we concomitantly used an alpha-glucosidase inhibitor with a LES and examined the effects on glucose tolerance. In addition, we examined whether or not there was an improvement in energy metabolism by slowing glucose absorption with the concomitant use of the alpha-glucosidase inhibitor.

METHODS

The subjects were 11 patients with liver cirrhosis. From before the study, all the patients had been taking a LES supplementation with a branched-chain amino acid (BCAA)-enriched nutrient mixture. The patients were started on the concomitant use of alpha-glucosidase inhibitor (0.2 mg) taken just prior to the LES. The change of glucose tolerance and energy metabolism were examined using a 75-g oral glucose tolerance test and indirect calorimetry.

RESULTS

One week and three months after the start of the concomitant use of the alpha-glucosidase inhibitor, the area under the concentration curve for plasma glucose was significantly decreased. Three months after the concomitant use, the non-protein respiratory quotient was significantly improved. There were no serious side effects during the follow-ups.

CONCLUSION

The concomitant use of the alpha-glucosidase inhibitor use with LES showed the possibility of improving glucose tolerance and energy metabolism. In patients with impaired glucose tolerance, the concomitant use of an alpha-glucosidase inhibitor with LES might be a useful measure for nutritional management.

Development from simple steatosis to liver cirrhosis and hepatocellular carcinoma: a 27-year follow-up case

Nonalcoholic fatty liver disease (NAFLD) is classified as nonalcoholic steatohepatitis (NASH) or simple steatosis (SS) according to histological findings. It is well recognized that NASH may develop into cirrhosis and hepatocellular carcinoma (HCC), both with unfavorable prognoses. Although the outlook of SS is reported to be better than that of NASH, the long-term prognosis of SS remains unclear. Here, we report the case of a patient who was diagnosed as having SS by a first liver biopsy, and later developed into cirrhosis and HCC over a period of 27 years. In 1980, a 42-year-old Japanese man was admitted because of abnormal liver function tests. He had no history of alcohol intake and was negative for hepatitis virus markers and autoantibodies. A liver biopsy specimen showed macrovesicular steatosis without ballooned hepatocytes, Mallory hyaline, lobular inflammation, or perisinusoidal/perivenular fibrosis, confirming the diagnosis of SS. The patient's serum aminotransferase levels did not normalize despite repeated dietary instruction, and in 2001, liver histology demonstrated cirrhosis with mild steatosis and hepatocyte ballooning, leading to the diagnosis of NASH-related cirrhosis. HCC appeared in 2007. Overall, this patient progressed to cirrhosis and HCC in 20 and 27 years, respectively, following initial diagnosis. Platelet counts and degree of steatosis, as assessed by periodic ultrasonography, were seen to gradually reduce with progression of fibrosis. This case demonstrates that even a diagnosis of SS does not guarantee non-progression to cirrhosis and HCC, and careful follow-up is needed not only in patients with NASH, but also in those with SS.

Increased risk of hepatocellular carcinoma among patients with hepatitis C cirrhosis and diabetes mellitus

Recent studies suggest that diabetes mellitus increases the risk of developing hepatocellular carcinoma (HCC). The aim of this study is to quantify the risk of HCC among patients with both diabetes mellitus and hepatitis C in a large cohort of patients with chronic hepatitis C and advanced fibrosis. We included 541 patients of whom 85 (16%) had diabetes mellitus. The median age at inclusion was 50 years. The prevalence of diabetes mellitus was 10.5% for patients with Ishak fibrosis score 4, 12.5% for Ishak score 5, and 19.1% for Ishak score 6. Multiple logistic regression analysis showed an increased risk of diabetes mellitus for patients with an elevated body mass index (BMI) (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.00-1.11; P = 0.060) and a decreased risk of diabetes mellitus for patients with higher serum albumin levels (OR, 0.81; 95% CI, 0.63-1.04; P = 0.095). During a median follow-up of 4.0 years (interquartile range, 2.0-6.7), 11 patients (13%) with diabetes mellitus versus 27 patients (5.9%) without diabetes mellitus developed HCC, the 5-year occurrence of HCC being 11.4% (95% CI, 3.0-19.8) and 5.0% (95% CI, 2.2-7.8), respectively (P = 0.013). Multivariate Cox regression analysis of patients with Ishak 6 cirrhosis showed that diabetes mellitus was independently associated with the development of HCC (hazard ratio, 3.28; 95% CI, 1.35-7.97; P = 0.009).

CONCLUSION

For patients with chronic hepatitis C and advanced cirrhosis, diabetes mellitus increases the risk of developing HCC.

Association between BMI and metabolic syndrome and adenomatous colonic polyps in Korean men

Obesity and insulin resistance are associated with the risk of colon cancer. Adenomatous colonic polyps are precancerous lesions of colon cancer. We investigated whether BMI and the metabolic syndrome are associated with the presence of adenomatous colonic polyps in Korean men. Anthropometric measurements, metabolic risk factors, and colonoscopic pathologic findings were assessed in 1,898 men who underwent routine colonoscopy at the Health Promotion Center of Asan Medical Center in 2005. The modified National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) and International Diabetes Federation (IDF) criteria were used for the definition of the metabolic syndrome. Multiple logistic regression analysis was used to evaluate the association between BMI and the metabolic syndrome and adenomatous polyps. Compared with men in the 1st quintile of the BMI, the adjusted odds ratio (OR) and 95% confidence interval (CI) for adenomatous polyps in men in the 2nd, 3rd, 4th, and 5th quintiles of the BMI were 1.55 (1.10-2.19), 1.57 (1.10-2.24), 1.94 (1.34-2.81), and 1.99 (1.31-3.01), respectively (P for trend <0.0001). Men with triglycerides (TGs) > or = 150 mg/dl were significantly more likely to have adenomatous polyps than were men with TG <150 mg/dl (OR 1.29; 95% CI 1.03-1.62). As a function of the number of metabolic risk factors, the ORs for adenomatous polyps were 1.41 (1.03-1.93), 1.52 (1.08-2.12), 1.46 (1.01-2.12), and 1.77 (1.08-2.90) for 1, 2, 3, and > or = 4 risk factors, respectively (P for trend <0.05). Adenomatous colonic polyps were significantly associated with increased BMI levels. Subjects with even one component of the metabolic syndrome had a significantly higher risk for developing adenomatous polyps compared to those subjects without any component in Korean men.

Inhibitory effect of branched-chain amino acid granules on progression of compensated liver cirrhosis due to hepatitis C virus

BACKGROUND

A phase II randomized controlled trial was conducted in patients with compensated liver cirrhosis to investigate the inhibitory effect of branched-chain amino acid (BCAA) granules for oral use (TK-98) on disease progression.

METHODS

Patients who had compensated liver cirrhosis due to hepatitis C virus with baseline serum albumin levels between 3.6 and 4.5 g/dl were assigned to the TK-98 group, which was treated with BCAA granules (TK-98) for 168 weeks, or to a control group (no treatment).

RESULTS

No symptoms indicating decompensated cirrhosis, including ascites, edema, and hepatic encephalopathy were reported in either the TK-98 or control group during the study observation period. Hepatocellular carcinoma (HCC) was noted in eight of the 39 patients studied, and of these three received TK-98 (15.8%) and five were untreated (25.0%). A time-to-event analysis for the effect of BCAA therapy on development of HCC revealed no statistically significant differences between the two groups. However, an additional analysis of data from a subgroup with a baseline serum albumin level of <4.0 g/dl showed that the incidence of HCC was likely to be lower in BCAA-treated patients.

CONCLUSIONS

BCAA may inhibit hepatic carcinogenesis in patients with compensated cirrhosis with a serum albumin level of <4.0 g/dl.

Branched-chain amino acids improve insulin resistance in patients with hepatitis C virus-related liver disease: report of two cases

Hepatitis C virus (HCV) infection causes insulin resistance. Because increased insulin resistance is a risk factor for development of hepatocellular carcinoma and reduced long-term survival, insulin resistance is a therapeutic target in patients with HCV infection. Branched-chain amino acids (BCAAs) are not only structural constituents of proteins but they are also considered as regulators of insulin signalling. We first describe two cases suggesting that administration of BCAAs improves insulin resistance associated with HCV-related liver disease. Although there were no changes in body weight, plasma glucose concentration and haemoglobin A1c (HbA1c) value were decreased. Moreover, BCAAs caused a decrease in both fasting insulin concentration and the value of homeostasis model assessment for insulin resistance. Thus, BCAAs are a potential therapeutic agent for improving insulin resistance in patients with HCV-related liver disease.

Primary liver cancers with nonalcoholic steatohepatitis

Nine patients with hepatocellular carcinoma (HCC) in nonalcoholic steatohepatitis (NASH) (six men and three women, median age 71.5 years) and one patient with intrahepatic cholangiocarcinoma (ICC), a 50-year-old man, in NASH are described. Most patients were associated with obesity, diabetes, hypertension, hypercholesterolemia, or hypertriglyceridemia. Seven patients showed insulin resistance and hyperinsulinemia. All patients except one met the criteria for metabolic syndrome. An HCC or ICC diagnosis was confirmed by tumor biopsy, surgery or autopsy except in two patients, who were diagnosed by computed tomography or hepatic angiography. The underlying liver disease was liver cirrhosis in six patients and chronic liver disease including mild hepatic fibrosis in four patients. The treatment of liver cancers consisted of surgery, radio-frequency ablation (RFA), transcatheter arterial embolization and transcatheter arterial infusion. Although the follow-up period was relatively short (median 27.5 months, average 32.1 months), all postoperative and post-RFA patients have not had a recurrence of HCC to date, except for one patient who had a palliative operation with intra-arterial infusion of anticancer drugs through an implanted reservoir port. Older age and liver cirrhosis are considered risk factors for HCC in NASH, and regular screening of these patients is necessary. Diabetes may contribute to the development of ICC in NASH. Curative therapy (surgery or RFA) and weight loss by the active therapeutic intervention (nutritional care and exercise therapy) after curative therapy may help us improve the prognosis of HCC in NASH.

Characterization of the molecular mechanisms involved in the increased insulin secretion in rats with acute liver failure

To investigate the mechanism of hyperinsulinaemia in rats with acute liver failure induced by the administration of d-galactosamine (GalN), we focused on the role of polyprimidine tract-binding protein (PTB) in islet insulin synthesis. Recent reports indicate that PTB binds and stabilizes mRNA encoding insulin and insulin secretory granule proteins, including islet cell autoantigen 512 (ICA512), prohormone convertase 1/3 (PC1/3), and PC2. In the present study, glucose-stimulated insulin secretion was significantly increased in GalN-treated rats compared to controls. Levels of mRNA encoding insulin 1, ICA512, and PC1/3 were increased in the pancreatic islets of GalN-treated rats. This mRNA level elevation was not prevented by pretreatment with actinomycin D. When the PTB-binding site in insulin 1 mRNA was incubated with the islet cytosolic fraction, the RNA-protein complex level was increased in the cytosolic fraction obtained from GalN-treated rats compared to the level in control rats. The cytosolic fraction obtained from pancreatic islets obtained from GalN-treated rats had an increased PTB level compared to the levels obtained from the pancreatic islets of control rats. These findings suggest that, in rats with acute liver failure, cytosolic PTB binds and stabilizes mRNA encoding insulin and its secretory granule proteins.

Impact of biomarkers on disease survival and progression in patients treated with octreotide for advanced hepatocellular carcinoma

BACKGROUND

Current determination of prognosis for advanced hepatocellular carcinoma (HCC) is mainly based on clinical assessment. We aimed to determine the impact of biomarkers as predictive factors for HCC progression and survival during octreotide-based treatments.

PATIENTS AND METHODS

We included patients who had been prospectively randomised to receive either octreotide (30 mg) alone monthly (n = 39) or in combination with rofecoxib (up to 50 mg bid daily, n = 32) for a minimum of 6 months, or until death occurred.

RESULTS

Overall median survival (154 days) and median time to progression (94 days) were not different for both treatments and the biomarkers investigated (VEGF-A, IGF-1, PGE-2, ET-A) were similarly distributed amongst treatment groups. Combined univariate group analysis revealed that survival was decreased for an uptake ratio of > 2 on initial octreoscan (P = 0.05); baseline serum VEGF-A and IGF-1 were further significantly associated with survival. On multivariate analysis, uncorrected serum VEGF-A appeared to be the most significant predictor for tumor progression and survival.

CONCLUSIONS

Biomarkers, in addition to established tumor markers, are independent predictors of tumor progression and survival in patients with advanced HCC treated with octreotide. Furthermore, the involvement of VEGF-A implies the inhibition of angiogenesis as a potential mechanism of action for this drug.

Sexual functioning in patients with hepatocellular carcinoma

BACKGROUND

The objectives of the current study were to assess the rates of sexual dysfunction in patients with hepatocellular carcinoma (HCC) and compare the rates of sexual morbidity with a sample of patients diagnosed with chronic liver disease (CLD) and the general population. It was expected that patients diagnosed with HCC would have a greater prevalence of sexual dysfunction than those diagnosed with CLD and the general population, respectively. Furthermore, those patients who reported a sexual dysfunction would also have a poorer quality of life (QOL).

METHODS

Twenty-one men diagnosed with HCC and 23 men diagnosed with CLD completed a battery of questionnaires that included the Sexual History Questionnaire and the Functional Assessment of Cancer Therapy-Hepatobiliary.

RESULTS

Results indicated that 41% of patients reported a current sexual problem (29% of HCC patients and 71% of patients with CLD) and 43% met the Diagnostic and Statistical Manual of Mental Disorders-4th edition (DSM-IV) criteria for at least 1 type of sexual dysfunction (25% of patients with HCC and 75% of patients with LD). Of the total sample, 68% reported being diagnosed with a comorbid medical condition or taking a medication that had potential sexual side effects. After eliminating cases with comorbid medical conditions and/or who were taking medications that contributed to sexual morbidity, the rate of sexual problems were found to be similar to that of the general population. Clinically significant differences were found with regard to the QOL. People who were experiencing sexual problems also reported a poorer QOL.

CONCLUSIONS

Although a large percentage of sexual dysfunction may have been secondary to comorbid medical problems and medications, treatment of the sexual dysfunction is still warranted.

Liver disease in patients with diabetes mellitus

Diabetes mellitus is a growing health concern in our society. In addition to the well-known cardiovascular, renal, and ophthalmologic complications of diabetes, liver-related complications occur commonly and are often underrecognized. The ensuing article will review the relationship between diabetes mellitus and two common liver diseases: chronic hepatitis C and nonalcoholic fatty liver disease. The association with diabetes and cirrhosis, acute liver failure, hepatocellular carcinoma, and outcomes following orthotopic liver transplantation will also be discussed.

Potent Gastric Acid Inhibition in Helicobacter pylori Eradication

At present, antisecretory drugs--foremost among them the proton pump inhibitors (PPIs)--represent a keystone in Helicobacter pylori eradication therapy. The present article shall first compare the role of PPIs as compared with histamine H2 receptor antagonists, both of them in the role of antibiotic-associated antisecretory therapy, and shall then address the contribution of each of the various PPIs that have been developed until the present time to the H. pylori eradication therapies. In summary, it may be concluded that PPIs are more effective overall than H2 receptor antagonists when the two groups of antisecretory drugs are given at the usual standard doses together with antibiotics with the intention of eradicating H. pylori infection. However, all PPIs (omeprazole, lansoprazole, pantoprazole, rabeprazole, and esomeprazole) are equivalent when given together with two antibiotics to cure the infection.

Insulin and dexamethasone inhibit TGF-beta-induced apoptosis of hepatoma cells upstream of the caspase activation cascade

Insulin and dexamethasone are potent inhibitors of apoptosis induced by transforming growth factor-beta1 (TGF-beta) in hepatoma cells. Using FTO-2B rat hepatoma cells, we determined whether the anti-apoptotic effects of these agents result from interference within or upstream of the TGF-beta-induced caspase cascade. Activation of different initiator and effector caspases, Bax and Bcl-xL expression, mitochondrial cytochrome c release and activation of PKB/Akt were analyzed by use of synthetic caspase substrates and Western blotting, respectively. TGF-beta-induced apoptosis was characterized by release of cytochrome c from mitochondria and activation of caspases-3, -7, -8 and -9. These effects were observable as early as 8-12 h after start of treatment and increased with time of observation. Inhibition of TGF-beta-induced apoptosis by insulin and dexamethasone was paralleled by a strong reduction of caspase-3-like activity. Caspase-8 activation was almost completely suppressed by these agents, and caspase-9 activity was decreased to levels within or slightly above unstimulated control cells. In addition, cytochrome c release from mitochondria was efficiently repressed, which was associated with upregulation of Bcl-xL by dexamethasone and activation of PKB/Akt by insulin. Thus, both anti-apoptotic compounds exert their inhibitory effects through modulation of anti-apoptotic signalling pathways involved in regulation of cytochrome c release and activation of the caspase machinery.

Expression of somatostatin receptors in normal and cirrhotic human liver and in hepatocellular carcinoma

BACKGROUND

Somatostatin analogues have been used with conflicting results to treat advanced hepatocellular carcinoma (HCC). The aim of this study was to investigate expression of somatostatin receptor (SSTR) subtypes in human liver, and to examine the effect of selective SSTR agonists on proliferation, apoptosis, and migration of hepatoma cells (HepG2, HuH7) and hepatic stellate cells (HSCs).

METHODS

Expression of SSTRs in cell lines, normal and cirrhotic liver, and HCC was examined by immunohistochemistry and reverse transcription-polymerase chain reaction. Effects of SSTR agonists on proliferation and apoptosis of tumour cells and HSCs were assessed by the 5-bromo-2' deoxyuridine and TUNEL methods, respectively. The influence of SSTR agonists on migration was investigated using Boyden chambers.

RESULTS

In normal liver, both hepatocytes and HSCs were negative for all five SSTRs. Cirrhotic liver and HCC as well as cultured hepatoma cells and HSCs expressed all five SSTRs, both at the protein and mRNA levels, except for HuH7 cells which did not immunoreact with SSTR3. None of the agonists influenced proliferation or apoptosis. However, compared with untreated cells, L-797,591, an SSTR1 agonist, reduced migration of HepG2, HuH7, and HSCs significantly to 88 (7)% (p<0.05), 83 (11)% (p<0.05), and 67 (13)% (p<0.01), respectively.

CONCLUSIONS

Cirrhotic liver and HCC express SSTRs. Although the somatostatin analogues used in this study did not affect proliferation and apoptosis, stimulation of SSTR1 may decrease invasiveness of HCC by reducing migration of hepatoma cells and/or HSCs. Clinical trials evaluating somatostatin analogues for the treatment of HCC should take these findings into account.

Elevated insulin, proinsulin and insulin-like growth factor-binding protein-1 in liver disease

Insulin-like growth factor-binding protein-1 (IGFBP-1) is one of six soluble binding proteins that regulate the actions of the insulin-like growth factors (IGFs). Liver is the major source of IGFBP-1 in non-pregnant humans. In normal physiology, IGFBP-1 transcription is potently inhibited by insulin and serum levels are limited by a rapid clearance rate. Elevated levels of IGFBP-1 in liver disease have been attributed to insulin resistance; however, the relationships between these analytes have not been defined. We studied insulin, proinsulin and IGFBP-1 in normal subjects (NL, N=47, 43+/-12 yr), cirrhosis (CIR, N=29, 54+/-14 yr), hepatocellular carcinoma (HCC, N=42, 61+/-11 yr), and other liver tumors (TUM, N=8, 60+/-17 yr). All three analytes were significantly increased in liver disease (mean+/-SEM; p-values relative to normals): IGFBP-1 (NL 24+/-4 ng/ml; CIR 235+/-53, p<0.0001; HCC 505+/-105, p<0.0001; TUM 118+/-36, p<0.0001), insulin (NL 72+/-4 pM; CIR 261+/-62, p<0.0002; HCC 180+/-25, p<0.0001; TUM 189+/-58, p<0.0001), proinsulin (NL 6.5+/-0.7 pM; CIR 36.8+/-7.7, p<0.0001; HCC 26.2+/-3.8, p<0.0001; TUM 32.1+/-9.7, p<0.0001). The ratio of proinsulin to insulin was also significantly elevated in liver disease. A typical curvilinear inverse relationship of insulin and IGFBP-1 was observed, but was shifted several fold higher for the liver disease groups. Our results demonstrate that insulin and proinsulin are elevated in liver disease. However, these elevations are paradoxically accompanied by elevated IGFBP-1 levels, indicating disruption of normal regulatory mechanisms. IGFBP-1 is postulated to play a dynamic role in metabolic substrate utilization via regulation of free IGF. Therefore, inappropriate elevation of IGFBP-1 could play an important role in the metabolic disturbances associated with liver disease.