Smoking as an independent risk factor for hepatocellular carcinoma: the Singapore Chinese Health Study

A Balanced Risk-Benefit Analysis to Determine Human Risks Associated with Pyrrolizidine Alkaloids (PA)-The Case of Tea and Herbal Infusions

Humans are exposed to pyrrolizidine alkaloids (PA) through different sources, mainly from contaminated foodstuff. Teas and herbal infusions (T&HI) can be contaminated by PA producing weed. PA can possess toxic, mutagenic, genotoxic, and carcinogenic properties. Thus, possible health risks for the general population are under debate. There is a strong safety record for T&HI and additionally epidemiological evidence for the preventive effects of regular tea consumption on cardiovascular events and certain types of cancer. There is no epidemiological evidence, however, for human risks of regular low dose PA exposure. Recommended regulatory PA-threshold values are based on experimental data only, accepting big uncertainties. If a general risk exists through PA contaminated T&HI, it must be small compared to other frequently accepted risks of daily living and the proven health effects of T&HI. Decision making should be based on a balanced riskbenefit analysis. Based on analyses of the scientific data currently available, it is concluded that the benefits of drinking T&HI clearly outweigh the negligible health risk of possible PA contamination. At the same time, manufacturers must continue their efforts to secure good product quality and to be transparent on their measures of quality control and risk communication.

Interactive effects between Lymphotoxin α +252 polymorphism and habits of substance use on risk of hepatocellular carcinoma

This case-control study aimed to assess the interactive effect between polymorphisms of lymphotoxin (LT) α +252 and habitual substance use on risk of hepatocellular carcinoma (HCC). We enrolled 150 pairs of sex- and age-matched HCC patients and unrelated healthy controls. LTα genotypes were detected with polymerase-chain reaction and restrictive fragment length polymorphisms. Information about habits of substance use was obtained through personal interview. Multivariate analysis indicated that LTα +252 G/G genotypes [odds ratio (OR) = 3.36], Hepatitis B surface antigen (OR = 16.68), antibodies to hepatitis C virus (OR = 34.88) and having at least two habits of substance use (OR = 2.50) were independent risk factors for HCC. There were additive interactions among LTα +252 G/G genotype, chronic viral hepatitis, and habit of each substance use.

IN CONCLUSION

There are independent and additive interactions between LTα +252 G/G genotype, chronic viral hepatitis, and habits of substance use on risk of HCC.

The Contribution of Matrix Metalloproteinase-1 Genotypes to Hepatocellular Carcinoma Susceptibility in Taiwan

BACKGROUND/AIM

Metalloproteinases (MMPs) are a family of proteases which have been shown to be overexpressed in various types of cancers. However, the contribution of MMP1 genotype to hepatocellular carcinoma (HCC) has not been well studied. This study aimed to evaluate the contribution of MMP1 promoter 1607 genotype to the risk of HCC in Taiwan, where HCC incidence is relatively high in the world.

MATERIALS AND METHODS

In this case-control study, MMP1 genotype and its interaction with consumption of cigarettes and alcohol in determining HCC risk was investigated among 298 HCC patients and 889 age- and gender-matched healthy controls.

RESULTS

The percentages of ever smokers and ever alcohol drinkers were much higher in the case group than in the control group. The percentages of 2G/2G, 1G/2G and 1G/1G for MMP1 promoter 1607 genotype were 37.2%, 38.3% and 24.5% in the HCC group and 34.8%, 44.0% and 21.2% in the control group, respectively (p for trend=0.2048). The allelic frequency distribution analysis showed the variant 1G allele of MMP1 promoter 1607 conferred similar HCC susceptibility as the wild-type 2G allele (odds ratio (OR)=1.01, 95% confidence interval (CI)=0.84-1.22, p=0.8735). As for the gene-lifestyle interaction, there was an obvious protective effect of MMP1 promoter 1607 1G allele on the risk of HCC among non-smokers, but not non-smokers, even alcohol drinkers or non-drinkers.

CONCLUSION

The 1G allele of MMP1 promoter 1607 may have a protective effect on HCC risk for non-smokers in Taiwan and further validations are needed in other population groups.

Alcohol use and smoking after liver transplantation; complications and prevention

The last thirty years have been very prosperous in the field of liver transplantation (LT), with great advances in organ conservation, surgical techniques, peri-operative management and long-term immunosuppression, resulting in improved patient and graft survival rates as well as quality of life. However, substance addiction after LT, namely alcohol and tobacco, results in short term morbidity together with medium and long-term mortality. The main consequences can be vascular (increased risk of hepatic artery thrombosis in smokers), hepatic (recurrent alcoholic cirrhosis in alcohol relapsers) and oncological (increased risk of malignancy in patients consuming tobacco and/or alcohol after LT). This issue has thus drawn attention in the field of LT research. The management of these two at-risk behaviors addictions need the implication of hepatologists and addiction specialists, before and after LT. This review will summarize our current knowledge in alcohol use and cigarette smoking in the setting of LT, give practical tools for identification of high risk patients and treatment options.

Impact of smoking habit on surgical outcomes in non-B non-C patients with curative resection for hepatocellular carcinoma

AIM

To analyzed the correlation between smoking status and surgical outcomes in patients with non-B non-C hepatocellular carcinoma (NBNC-HCC), and we investigated the patients’ clinicopathological characteristics according to smoking status.

METHODS

We retrospectively analyzed the consecutive cases of 83 NBNC-HCC patients who underwent curative surgical treatment for the primary lesion at Saga University Hospital between 1984 and December 2012. We collected information about possibly carcinogenic factors such as alcohol abuse, diabetes mellitus, obesity and smoking habit from medical records. Smoking habits were subcategorized as never, ex- and current smoker at the time of surgery. The diagnosis of non-alcoholic steatohepatitis (NASH) was based on both clinical information and pathological confirmation.

RESULTS

Alcohol abuse, diabetes mellitus, obesity and NASH had no significant effect on the surgical outcomes. Current smoking status was strongly correlated with both overall survival (P = 0.0058) and disease-specific survival (P = 0.0105) by multivariate analyses. Subset analyses revealed that the current smokers were significantly younger at the time of surgery (P = 0.0002) and more likely to abuse alcohol (P = 0.0188) and to have multiple tumors (P = 0.023).

CONCLUSION

Current smoking habit at the time of surgical treatment is a risk factor for poor long-term survival in NBNC-HCC patients. Current smokers tend to have multiple HCCs at a younger age than other patients.

Glucocorticoid receptor contributes to the altered expression of hepatic cytochrome P450 upon cigarette smoking

Cigarette smoking has been shown to cause pathological alterations in the liver. However, how hepatic metabolism is altered during cigarette smoking‑induced inflammation remains to be fully elucidated. In the present study, a rat model of smoking was established to examine the effects of cigarette smoking on inflammation, autophagy activity, and the expression of nuclear receptor and CYP in the liver. Elevated expression of interleukin 1β and activation of autophagy in the liver were observed upon smoking exposure in rats. Cigarette smoking induced a significant reduction in the mRNA expression levels of cytochromes, including cytochrome P450 (Cyp)1A2, Cyp2D4 and Cyp3A2. Accordingly, a decrease was also observed in glucocorticoid receptor (GR), a regulator of the expression of Cyp. Activation of the GR signal in human hepatic LO2 cells did not affect autophagic genes, however, it led to the upregulation of hCYP1A2, hCYP2C19 and hCYP3A4, and the downregulation of hCYP2C9. The GR antagonist, RU486, eliminated this effect, suggesting the importance of GR in liver metabolism upon cigarette smoking.

Prevalence of hepatocellular carcinoma in chronic hepatitis C patients in Mid Delta, Egypt: A single center study

BACKGROUND AND AIM

Hepatocellular carcinoma (HCC) has an increasing incidence worldwide. In this study we aimed to assess the prevalence of HCC among HCV patients in our center in Mid Delta, Egypt.

PATIENTS AND METHODS

During the period between April 2013 and January 2015, we screened sequentially chronic HCV patients attending inpatient wards or outpatient Clinic of Tropical Medicine Department in Tanta University Hospital for HCC. Individuals with focal lesion in Ultrasound (US) and/or serum α-fetoprotein (AFP) level >200ng/ml were examined by triphasic computed tomography scanning (CT), and/or magnetic resonance imaging (MRI).

RESULTS

Among 514 HCV patients interviewed and accepted sharing in this study, 90 (17.5%), 144 (28%), and 280 (54.5%) were Child A, B, and C, respectively. We found that 108/514 patients (21%) had focal lesion detected by US. Also, 89/514 (17.3%) had elevated AFP >200, 13 of them (14.6%) had no focal lesion on US, but further work up showed HCC in 2 of them. Overall HCC diagnosis was confirmed in 103 cases, 94 of them (91.3%) were Child B or C. Occurrence of HCC was significantly higher in smokers, diabetics, patients with decompensated liver and those with positive family history of HCC. Only 20/103 (19.4%) were candidates to curative treatments, 8 of them were Child A asymptomatic and discovered accidentally during screening.

CONCLUSION

The high prevalence of HCC in our HCV patients (22%) was mainly associated with decompensated cirrhosis. A national surveillance program for the detection of HCC in cirrhotic HCV Egyptian patients by combining ultrasound examination and AFP is highly recommended.

Cancer incidence attributable to alcohol consumption in Alberta in 2012

BACKGROUND

Alcohol consumption has been associated with risk of oral cavity/pharyngeal, laryngeal, esophageal, liver, colorectal and breast cancers. The purpose of this study was to estimate the proportion and total number of these cancers in Alberta in 2012 attributable to alcohol consumption.

METHODS

We estimated cancers attributable to alcohol consumption in adults in Alberta using population attributable risk calculations. Relative risks were obtained from recent meta-analyses, and alcohol consumption in Alberta was quantified with the use of data from the Canadian Community Health Survey. We obtained age-, site- and sex-specific cancer incidence data for 2012 from the Alberta Cancer Registry. The impact of potential underestimation of alcohol consumption in Canadian Community Health Survey data was evaluated with the use of per-capita alcohol sales data from Statistics Canada.

RESULTS

Proportions of cancers attributable to alcohol consumption at individual cancer sites were estimated to be as low as 5.1% (liver) and as high as 19.9% (oral cavity/pharynx) among men and as low as 2.1% (liver) and as high as 7.6% (oral cavity/pharynx) among women in Alberta. The total number of alcohol-attributable cancer cases was highest for common cancers (colorectal, female breast), whereas at individual cancer sites, population attributable risks were highest for upper aerodigestive tract cancers. A total of 4.8% of alcohol-associated cancers (1.6% of all cancers) in Alberta could be attributed to alcohol consumption. After adjustment for recorded alcohol consumption, our estimates of population attributable risk increased to 10.7% of alcohol-associated cancers and 3.5% of all cancers.

INTERPRETATION

Alcohol consumption is estimated to account for 1.6%-3.5% of total cancer cases in Alberta. Given that no level of alcohol consumption is considered safe with respect to cancer risk, strategies to reduce alcohol consumption have the potential to reduce Alberta's cancer burden.

Liver-related mortality in countries of the developed world: an ecological study approach to explain the variability

BACKGROUND

Liver-related mortality varies across developed nations.

AIM

To assess the relative role of various risk factors in relation to liver-related mortality in an ecological study approach.

METHODS

Data for liver-related mortality, prevalence data for hepatitis B and C, human immunodeficiency virus (HIV), alcohol consumption per capita, Type 2 Diabetes mellitus (T2DM), overweight and obesity were extracted from peer-reviewed publications or WHO databases for different developed countries. As potential other risk-modifying factors, purchase power parity (PPP)-adjusted gross domestic product (GDP) per capita and health expenditure per capita were assessed. As an environmental 'hygiene factor', we also assessed the effect of the prevalence of Helicobacter pylori. Only countries with a PPP-adjusted GDP greater than $20 000 and valid information for at least 8 risk modifiers were included. Univariate and multivariate analyses were utilised to quantify the contribution to the variability in liver-related mortality.

RESULTS

The proportion of chronic liver diseases (CLD)-related mortality ranged from 0.73-2.40% [mean 1.56%, 95% CI (1.43-1.69)] of all deaths. Univariately, CLD-related mortality was significantly associated with Hepatitis B prevalence, alcohol consumption, PPP-adjusted GDP (all P < 0.05) and potentially H. pylori prevalence (P = 0.055). Other investigated factors, including hepatitis C, did not yield significance. Backward elimination suggested hepatitis B, alcohol consumption and PPP-adjusted GDP as risk factors (explaining 66.3% of the variability).

CONCLUSION

Hepatitis B infection, alcohol consumption and GDP, but not hepatitis C or other factors, explain most of the variance of liver-related mortality.

Dietary fatty acids and risk of hepatocellular carcinoma in the Singapore Chinese health study

BACKGROUND & AIM

Lipidomic signature of lipid metabolism suggests that omega-6 polyunsaturated fatty acids (PUFA) may play a role in oncogenesis of hepatocellular carcinoma (HCC). Hence, we examined the association between dietary fatty acids and risk of HCC.

METHODS

We used data from the Singapore Chinese Health Study, a population-based prospective cohort of 63 257 Chinese men and women aged 45-74 years enrolled between 1993 and 1998. Information on current diet assessed via a validated semi-quantitative food frequency questionnaire, medical history and lifestyle factors were obtained through in-person interview, and incidence of HCC recorded through 31 Dec 2010. We also examined the association between dietary fatty acids and HCC risk using a case-control set of 92 cases and 274 controls with available serological biomarkers of chronic infections with hepatitis B virus (HBV) and hepatitis C virus (HCV) nested within this cohort.

RESULTS

Among the dietary fat components examined, which included saturated, monounsaturated, omega-3 and omega-6 PUFA, only omega-6 PUFA intake displayed a dose-dependent, positive association with HCC risk (p for trend = 0.02). Compared to the lowest quartile, the hazard ratio for the highest quartile intake was 1.49 [(95% confidence interval (CI):1.08-2.07)]. In the nested case-control study, only among individuals negative for serology markers of chronic infection with HBV or HCV, those who consumed above median levels of dietary omega-6 PUFA had increased HCC risk (odds ratio = 4.36, 95% CI = 1.59-11.94) compared to those with lower intake.

CONCLUSION

Dietary omega-6 PUFA may be implicated in the risk of non-viral hepatitis related HCC.

Hepatocellular carcinoma and lifestyles

The majority of hepatocellular carcinoma occurs over pre-existing chronic liver diseases that share cirrhosis as an endpoint. In the last decade, a strong association between lifestyle and hepatocellular carcinoma has become evident. Abundance of energy-rich food and sedentary lifestyles have caused metabolic conditions such as obesity and diabetes mellitus to become global epidemics. Obesity and diabetes mellitus are both tightly linked to non-alcoholic fatty liver disease and also increase hepatocellular carcinoma risk independent of cirrhosis. Emerging data suggest that physical activity not only counteracts obesity, diabetes mellitus and non-alcoholic fatty liver disease, but also reduces cancer risk. Physical activity exerts significant anticancer effects in the absence of metabolic disorders. Here, we present a systematic review on lifestyles and hepatocellular carcinoma.

Factors affecting the recurrence and survival of hepatocellular carcinoma after hepatectomy: a retrospective study of 601 Chinese patients

OBJECTIVE

Indications for resection of hepatocellular carcinoma (HCC) remain controversial. This study aimed to identify prognostic factors that affect overall survival (OS) and disease-free survival (DFS) in patients with HCC after hepatectomy.

METHODS

From 2004 to 2010, 601 patients with HCC who underwent resection were enrolled. Factors stratified into the host, biochemical, surgical treatment and tumor-related features in terms of recurrence and overall survival were analyzed. Prognostic factors were evaluated by univariate and multivariate analyses, with Kaplan-Meier survival analyses and Cox proportional hazard model.

RESULTS

The overall survival rates of 1-, 3- and 5- year were 79, 62, and 54 %, and the corresponding DFS rates were 51, 38 and 31 %, respectively. In a multivariate analysis, Child-Pugh, serum AFP level, ALT level, time for hepatic resection, tumor differentiation, maximum size of tumors, local necrosis, portal vein tumor thrombus, and TNM Stage were correlated significantly with patients' OS. Gender (P = 0.046), cigarette smoking (P = 0.007), serum AFP level (P = 0.001), GGT level (P = 0.002), maximum size of tumors (P = 0.009), liver cirrhosis (P = 0.025), portal vein tumor thrombus (P = 0.022), microvascular tumor thrombus (P = 0.007) and TNM Stage (P = 0.001) were significantly affected DFS.

CONCLUSION

Preoperative AFP level, maximum size of tumors, portal vein tumor thrombus and TNM Stage were revealed as important prognostic factors for OS and DFS through follow-up of a relatively large cohort of Chinese HCC patients.

HDAC1 and HDAC2 independently predict mortality in hepatocellular carcinoma by a competing risk regression model in a Southeast Asian population

Histone deacetylases (HDACs) are enzymes involved in transcriptional repression. We aimed to examine the significance of HDAC1 and HDAC2 gene expression in the prediction of recurrence and survival in 156 patients with hepatocellular carcinoma (HCC) among a South East Asian population who underwent curative surgical resection in Singapore. We found that HDAC1 and HDAC2 were upregulated in the majority of HCC tissues. The presence of HDAC1 in tumor tissues was correlated with poor tumor differentiation. Notably, HDAC1 expression in adjacent non-tumor hepatic tissues was correlated with the presence of satellite nodules and multiple lesions, suggesting that HDAC1 upregulation within the field of HCC may contribute to tumor spread. Using competing risk regression analysis, we found that increased cancer-specific mortality was significantly associated with HDAC2 expression. Mortality was also increased with high HDAC1 expression. In the liver cancer cell lines, HEP3B, HEPG2, PLC5, and a colorectal cancer cell line, HCT116, the combined knockdown of HDAC1 and HDAC2 increased cell death and reduced cell proliferation as well as colony formation. In contrast, knockdown of either HDAC1 or HDAC2 alone had minimal effects on cell death and proliferation. Taken together, our study suggests that both HDAC1 and HDAC2 exert pro-survival effects in HCC cells, and the combination of isoform-specific HDAC inhibitors against both HDACs may be effective in targeting HCC to reduce mortality.

Hepatocellular Carcinoma in Patients with a Sustained Response to Anti-Hepatitis C Therapy

Hepatocellular carcinoma (HCC) is a common, life-threatening complication of longstanding infection with the hepatitis C virus (HCV), likely a consequence of the direct oncogenic activity of the virus cooperating with liver cell inflammation in transforming the liver into a mitogenic and mutagenic environment. The achievement of a sustained virological response (SVR) to interferon-based therapies has been shown to benefit the course of hepatitis C in terms of reduced rates of liver-related complications and mortality from all causes. Interestingly, while achievement of an SVR is associated with a negligible risk of developing clinical decompensation over the years, the risk of HCC is not fully abrogated following HCV clearance, but it remains the dominant complication in all SVR populations. The factors accounting for such a residual risk of HCC in SVR patients are not fully understood, yet the persistence of the subverted architecture of the liver, diabetes and alcohol abuse are likely culprits. In the end, the risk of developing an HCC in SVR patients is attenuated by 75% compared to non-responders or untreated patients, whereas responders who develop an HCC may be stratified in different categories of HCC risk by a score based on the same demographic and liver disease-based variables, such as those that predict liver cancer in viremic patients. All in all, this prevents full understanding of those factors that drive HCC risk once HCV has been eradicated. Here, we critically review current understanding of HCC in SVR patients focusing on factors that predict residual risk of HCC among these patients and providing a glimpse of the expected benefits of new anti-HCV regimens based on direct antiviral agents.

Alcohol consumption and liver cancer risk: a meta-analysis

PURPOSE

Alcohol is a confirmed risk factor of liver cancer. Yet, its dose-response function and synergistic effects with other risk factors remain unclear.

METHODS

We performed a meta-analysis on publications up to May 2014. A total of 112 publications were identified. The meta-relative risk (mRR) and the dose-response trend were calculated. Tests for heterogeneity, publication bias, and sensitivity analyses were performed. The synergy index (SI) was recorded or calculated, whenever possible.

RESULTS

Compared to individuals who never drank or drank at very low frequencies, the mRR for ever drinkers was 1.29 (95% confidence interval, CI 1.16-1.42) and 1.46 (95% CI 1.27-1.65) for case-control studies, and 1.07 (95% CI 0.87-1.27) for cohort studies. Being a current drinker was associated with an increased liver cancer risk in case-control studies (mRR = 1.55, 95% CI 0.38-2.73), but not in cohort studies (mRR = 0.86, 95% CI 0.74-0.97). The dose-response relation between alcohol and liver cancer was apparent with RR = 1.08 (95% CI 1.04-1.11) for 12 g/day (~1 drink), 1.54 (95% CI 1.36-1.74) for 50 g/day, 2.14 (95% CI 1.74-2.62) for 75 g/day, 3.21 (95% CI 2.34-4.40) for 100 g/day, and 5.20 (95% CI 3.25-8.29) for 125 g/day of alcohol consumption. There were synergistic effects of alcohol consumption with hepatitis (S = 2.14, 95% CI 1.31-2.98) and with diabetes (S = 3.57, 95% CI 2.29-4.84) on the risk of liver cancer, although this may be subject to publication bias.

CONCLUSION

Overall, one alcoholic drink per day (~12 g/day) may be associated with a 1.1 times higher liver cancer risk. Further studies on the synergistic effects of alcohol consumption and other major risk factors are warranted.

Risk factors for hepatocellular carcinoma in Caucasian patients with non-viral cirrhosis: the importance of prior obesity

BACKGROUND & AIMS

In patients with cirrhosis, the risk of hepatocellular carcinoma (HCC) depends upon age, gender and the etiology of liver disease. Few studies are available in Caucasian patients with alcoholic or metabolic cirrhosis without viral hepatitis.

METHODS

Cross-sectional clinical data from 905 HCV- and HBV-negative Caucasian patients with alcoholic or metabolic cirrhosis were prospectively collected in four French centres. The risk factors for HCC were identified by logistic regression analysis in the whole population and in a nested case-control study.

RESULTS

The etiology of cirrhosis was alcoholic (48%), metabolic (7%) or mixed (45%). Patients were predominantly male (80%), mean age 62 years old and 31% had HCC. Mean body mass index (BMI) was 27 ± 5 and 30% were obese at inclusion. The maximum BMI reached throughout life was 31 ± 6 and 63% had been obese. Ninety percent of the population had daily alcohol consumption, 73% were smokers. Hepatocellular carcinoma was independently related to male gender (P < 0.0001), older age (P < 0.0001), past obesity (P = 0.007), diabetes (P = 0.037), abnormal levels of transaminases (P < 0.0001) and tobacco consumption (P = 0.007). The case-control study (200 HCC cases matched with 400 non-HCC cases for gender, age and Child-Pugh score) confirmed past obesity, tobacco and abnormal levels of transaminases.

CONCLUSIONS

Beside diabetes, male gender and age, a past history of obesity, but not an existing overweight, as well as exposure to tobacco and elevated transaminases were three risk factors which could improve the strategy for HCC screening in Caucasian cirrhotic patients without hepatitis B or C.

Combined effects of six cytokine gene polymorphisms and SNP-SNP interactions on hepatocellular carcinoma risk in Southern Guangxi, China

Cytokine gene single nucleotide polymorphisms (SNPs) are involved in the genesis and progression of hepatocellular carcinoma (HCC). We hypothesized that combined effects of cytokine gene SNPs and SNP-SNP interactions are associated with HCC risk. Six SNPs in cytokine genes (IL-2, IFN-γ, IL-1β, IL-6, and IL-10) were genotyped in a study of 720 Chinese HCC cases and 784 cancer-free controls. Although none of these SNPs individually had a significant effect on the risk of HCC, we found that the combined effects of these six SNPs may contribute to HCC risk (OR=1.821, 95% CI=1.078-3.075). This risk was pronounced among smokers, drinkers, and hepatitis B virus carriers. A SNP-SNP interaction between IL-2-330 and IFN-γ-1615 was associated with an increased HCC risk (OR=1.078, 95% CI=1.022-1.136). In conclusion, combined effects of SNPs and SNP-SNP interactions in cytokine genes may contribute to HCC risk.

The evolving epidemiology of hepatocellular carcinoma: a global perspective

Primary liver cancer, the majority of which are hepatocellular carcinomas, is now the second leading cause of cancer death worldwide. Hepatocellular carcinoma is a unique cancer that typically arises in the setting of chronic liver disease at a rate dependent upon the complex interplay between the host, disease and environmental factors. Infection with chronic hepatitis B or C virus is currently the dominant risk factor worldwide. However, changing lifestyle and environmental factors in western countries plus rising neonatal hepatitis B vaccination rates and decreasing exposure to dietary aflatoxins in developing countries are driving an evolution of the epidemiology of this cancer. An understanding of this change is crucial in combating the rising incidence currently being seen in western regions and will underpin the efforts to reduce the mortality rates associated with this cancer.

Diagnosis and treatment of hepatocellular carcinoma: An update

Hepatocellular carcinoma (HCC) is one of the most common malignancies leading to high mortality rates in the general population; in cirrhotic patients, it is the primary cause of death. The diagnosis is usually delayed in spite of at-risk population screening recommendations, i.e., patients infected with hepatitis B or C virus. Hepatocarcinogenesis hinges on a great number of genetic and molecular abnormalities that lead to tumor angiogenesis and foster their dissemination potential. The diagnosis is mainly based on imaging studies such as computed tomography and magnetic resonance, in which lesions present a characteristic classical pattern of early arterial enhancement followed by contrast medium “washout” in late venous phase. On occasion, when imaging studies are not conclusive, biopsy of the lesion must be performed to establish the diagnosis. The Barcelona Clinic Liver Cancer staging method is the most frequently used worldwide and recommended by the international guidelines of HCC management. Currently available treatments include tumor resection, liver transplant, sorafenib and loco-regional therapies (alcoholization, radiofrequency ablation, chemoembolization). The prognosis of hepatocarcinoma is determined according to the lesion’s stage and in cirrhotic patients, on residual liver function. Curative treatments, such as liver transplant, are sought in patients diagnosed in early stages; patients in more advanced stages, were not greatly benefitted by chemotherapy in terms of survival until the advent of target molecules such as sorafenib.

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

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

Cigarette smoking increases risk of early morbidity after hepatic resection in patients with hepatocellular carcinoma

AIMS

Cigarette smoking is an important risk factor for the development of postoperative pulmonary complications after major surgical procedures. The objective of this study was to investigate whether preoperative smoking has any impact on early morbidity after liver resection for hepatocellular carcinoma (HCC).

METHODS

Data of 425 consecutive patients undergoing partial hepatectomy for HCC was retrospectively reviewed. Smoking and drinking habits, biochemical tests, tumor status, operation data, and any postoperative complications occurring before discharge from the hospital were documented. The risk factors promoting postoperative complications were analyzed by univariate and multivariate methods.

RESULTS

The overall morbidity rate was 40% (170 of 425). 166 patients were current smokers (39%). By multivariate analysis, liver cirrhosis (Risk Ratio (RR) 4.0, 95% confidence interval (CI) 2.0-8.0), smoking status (RR 3.0, 95% CI 1.7-5.1), PY of smoking (RR 1.3, 95% CI 1.1-1.9), preoperative platelet count (RR 1.6, 95% CI 1.4-2.0) and major hepatectomy (RR 1.4, 95% CI 1.1-1.8) were independent risk factors of postoperative morbidity (all p < 0.05). Liver failure, bile leakage, intractable ascites, chest and wound infection were more frequently occurred in smokers than non-smokers. Current smokers had higher postoperative morbidity than non- & former smokers in patients with normal liver and those with liver cirrhosis (p = 0.047 and p < 0.001, respectively).

CONCLUSIONS

Cigarette smoking is an independent risk factor for the development of liver-related and infectious complications in patients undergoing partial hepatectomy for HCC, especially in those with liver cirrhosis.

Molecular Links between Alcohol and Tobacco Induced DNA Damage, Gene Polymorphisms and Patho-physiological Consequences: A Systematic Review of Hepatic Carcinogenesis

Chronic alcohol and tobacco abuse plays a crucial role in the development of different liver associated disorders. Intake promotes the generation of reactive oxygen species within hepatic cells exposing their DNA to continuous oxidative stress which finally leads to DNA damage. However in response to such damage an entangled protective repair machinery comprising different repair proteins like ATM, ATR, H2AX, MRN complex becomes activated. Under abnormal conditions the excessive reactive oxygen species generation results in genetic predisposition of various genes (as ADH, ALDH, CYP2E1, GSTT1, GSTP1 and GSTM1) involved in xenobiotic metabolic pathways, associated with susceptibility to different liver related diseases such as fibrosis, cirrhosis and hepatocellular carcinoma. There is increasing evidence that the inflammatory process is inherently associated with many different cancer types, including hepatocellular carcinomas. The generated reactive oxygen species can also activate or repress epigenetic elements such as chromatin remodeling, non-coding RNAs (micro-RNAs), DNA (de) methylation and histone modification that affect gene expression, hence leading to various disorders. The present review provides comprehensive knowledge of different molecular mechanisms involved in gene polymorphism and their possible association with alcohol and tobacco consumption. The article also showcases the necessity of identifying novel diagnostic biomarkers for early cancer risk assessment among alcohol and tobacco users.

Hepatocellular carcinoma epidemiology

Primary liver cancer (namely hepatocellular carcinoma, HCC) is worldwide the fifth most common cancer in men and the seventh one in women, and it represents the third most frequent cause of cancer death. HCC rates are particularly high in eastern/south-eastern Asia and in Africa, intermediate in Southern Europe, and low in most high-income countries. Persistent infections by HBV or HCV are the main recognized risk factors for HCC. Aflatoxin exposure is also an important risk factor for HCC development in Africa and eastern Asia. In high-income countries heavy alcohol drinking, tobacco smoking, overweight, diabetes, familial/genetic factors, and selected dietary aspects, have a relevant role. Updated geographic patterns and time trends in mortality from HCC in Europe, USA, Japan, and Australia are provided in the present review, together with an overview of relevant etiologic factors for HCC and main measures for the prevention of this neoplasm.

Serum albumin level is a notable profiling factor for non-B, non-C hepatitis virus-related hepatocellular carcinoma: A data-mining analysis

AIM

Various factors are underlying for the onset of non-B, non-C hepatitis virus-related hepatocellular carcinoma (NBNC-HCC). We aimed to investigate the independent risk factors and profiles associated with NBNC-HCC using a data-mining technique.

METHODS

We conducted a case-control study and enrolled 223 NBNC-HCC patients and 669 controls from a health checkup database (n = 176 886). Multivariate analysis, random forest analysis and a decision-tree algorithm were employed to examine the independent risk factors, factors distinguishing between the case and control groups, and to identify profiles for the incidence of NBNC-HCC, respectively.

RESULTS

In multivariate analysis, besides γ-glutamyltransferase (GGT) levels and the Brinkman index, albumin level was an independent negative risk factor for the incidence of NBNC-HCC (odds ratio = 0.67; 95% confidence interval = 0.60-0.70; P < 0.0001). In random forest analysis, serum albumin level was the highest-ranked variable for distinguishing between the case and control groups (98 variable importance). A decision-tree algorithm was created for albumin and GGT levels, the aspartate aminotransferase-to-platelet ratio index (APRI) and the Brinkman index. The serum albumin level was selected as the initial split variable, and 82.5% of the subjects with albumin levels of less than 4.01 g/dL were found to have NBNC-HCC.

CONCLUSION

Data-mining analysis revealed that serum albumin level is an independent risk factor and the most distinguishable factor associated with the incidence of NBNC-HCC. Furthermore, we created an NBNC-HCC profile consisting of albumin and GGT levels, the APRI and the Brinkman index. This profile could be used in the screening strategy for NBNC-HCC.

Coffee, alcohol and other beverages in relation to cirrhosis mortality: the Singapore Chinese Health Study

Limited experimental and epidemiologic data suggest that coffee may reduce hepatic damage in chronic liver disease. The association between consumption of coffee and other beverages and risk of cirrhosis mortality was evaluated in the Singapore Chinese Health Study. This is a prospective population-based cohort of 63,275 middle-aged and older Chinese subjects who provided data on diet, lifestyle, and medical histories through in-person interviews using a structured questionnaire at enrollment between 1993 and 1998. Mortality from cirrhosis in the cohort was ascertained through linkage analysis with nationwide death registry. After a mean follow-up of 14.7 years, 114 subjects died from cirrhosis; 33 of them from viral hepatitis B (29%), two from hepatitis C (2%), and 14 from alcohol-related cirrhosis (12%). Compared to nondrinkers, daily alcohol drinkers had a strong dose-dependent positive association between amount of alcohol and risk of cirrhosis mortality. Conversely, there was a strong dose-dependent inverse association between coffee intake and risk of nonviral hepatitis-related cirrhosis mortality (P for trend = 0.014). Compared to non-daily coffee drinkers, those who drank two or more cups per day had a 66% reduction in mortality risk (hazard ratio [HR] = 0.34, 95% confidence interval [CI] = 0.14-0.81). However, coffee intake was not associated with hepatitis B-related cirrhosis mortality. The inverse relationship between caffeine intake and nonviral hepatitis-related cirrhosis mortality became null after adjustment for coffee drinking. The consumption of black tea, green tea, fruit juices, or soft drinks was not associated with risk of cirrhosis death.

CONCLUSION

This study demonstrates the protective effect of coffee on nonviral hepatitis-related cirrhosis mortality, and provides further impetus to evaluate coffee as a potential therapeutic agent in patients with cirrhosis.

Prognosis of patients with hepatocellular carcinoma and hypersplenism after surgery: a single-center experience from the People's Republic of China

PURPOSE

As prognosis of patients with hepatocellular carcinoma (HCC) and hypersplenism is rarely reported, this study examined prognostic factors for patients who underwent surgery for this condition.

PATIENTS AND METHODS

This study retrospectively analyzed prognostic factors in 181 consecutive HCC patients using univariate and multivariate analyses, as well as subgroup analyses for disease-free survival (DFS) and overall survival (OS) of two groups: one group who received splenectomies (Sp) and one group who did not (non-Sp).

RESULTS

1, 3, and 5 year OS rates were 88.4%, 67.1%, and 52.8%, respectively; corresponding DFS rates were 67.0%, 43.8%, and 31.6%, respectively. Age ≥55 years old, cigarette smoking, tumor size ≥5 cm, microvascular invasion, and Child-Pugh grade B (versus A) correlated significantly with OS (P<0.05). Interestingly, in patients with tumor lymph node metastasis (TNM) stage I disease, DFS of the Sp-group (median DFS, 24.1 months; n=34) was significantly lower than that of the non-Sp group (median DFS, 62.1 months; n=74), P=0.034; whereas at TNM stage II, OS of the Sp-group (median OS, 79.1 months; n=21) was significantly better than that of the non-Sp group (median OS, 23.3 months; n=30), P=0.018.

CONCLUSION

Hepatectomy without concomitant splenectomy can contribute to improved DFS of TNM stage I HCC patients with hypersplenism, whereas simultaneous hepatectomy and splenectomy can prolong OS for patients at TNM stage II.

Expression of aldo-keto reductase family 1 member b10 in the early stages of human hepatocarcinogenesis

Aldo-keto reductase family 1, member B10 (AKR1B10), a cancer-related oxidoreductase, is expressed in well-differentiated hepatocellular carcinomas (HCCs). However, AKR1B10 levels are minimal in normal liver tissues (NLs), similar to the 70-kilodalton heat shock protein (HSP70) and glypican-3. Moreover, the role of AKR1B10 in chronic hepatitis or cirrhosis, which are considered preneoplastic conditions for HCC, has not been fully elucidated. The aim of this study was to evaluate the expression of AKR1B10, HSP70, and glypican-3 in 61 HCC tissue samples compared to corresponding non-tumorous liver tissues (NTs), comprising 42 chronic hepatitis and 19 cirrhosis cases to clarify the significance of molecular changes at the preneoplastic stages of HCC. Immunohistochemical analysis demonstrated that the median expression levels of AKR1B10 were higher in HCCs than in NTs (p < 0.001) and higher in NTs than NLs (p < 0.001) with 54.8%, 2.1%, and 0.3% expression in HCCs, NTs, and NLs, respectively. HSP70 and glypican-3 were expressed in HCCs, but minimally in NTs and NLs with no significant difference between expression in NTs and NLs. Furthermore, a multivariate analysis identified an association between hepatic steatosis and AKR1B10 expression in NTs (p = 0.020). Of the three protein expressed in well-differentiated HCCs, only AKR1B10 was upregulated in preneoplastic conditions, and a steatosis-related factor might influence its expression.

Alcohol and liver cancer: a systematic review and meta-analysis of prospective studies

Despite several studies support a positive association between heavy alcohol consumption and liver cancer risk, a consistent dose-risk relationship has not yet been established. We carried out a systematic review and a meta-analysis of the association between alcohol intake and liver cancer occurrence, following the Meta-analysis Of Observational Studies in Epidemiology guidelines. We searched for cohort and nested case-control studies on the general population published before April 2013, using PubMed and EMBASE. Summary meta-analytic relative risks (RRs) were estimated using random-effect models. We included 16 articles (19 cohorts) for a total of 4445 incident cases and 5550 deaths from liver cancer. Compared with non-drinking, the pooled RRs were 0.91 (95% confidence interval, CI, 0.81-1.02) for moderate drinking (< 3 drinks per day) and 1.16 (95% CI, 1.01-1.34) for heavy drinking (≥ 3 drinks per day), with significant heterogeneity among studies. The dose-risk curve suggested a linear relationship with increasing alcohol intake in drinkers, with estimated excess risk of 46% for 50 g of ethanol per day and 66% for 100 g per day. This systematic review suggests a moderate detrimental role of consumption of 3 or more alcoholic drinks per day on liver cancer, and a lack of association with moderate drinking. Our results have to be taken with due caution on account of the possible limitations of the original studies included in the meta-analysis.

The magnitude of the association between smoking and the risk of developing cancer in Brazil: a multicenter study

OBJECTIVES

To estimate the magnitude of association and identify the aetiological fraction (AF) attributable to smoking in the development of different types of cancers in Brazil.

SETTING

We conducted a case-control study, including 231 102 patients registered in the Cancer Hospital Registries (CHR) in the period from 1998 to 2011.

PARTICIPANTS

A total of 204 131 cancer cases relating to 30 topographies were compared with 26 971 cases of non-melanoma skin cancer.

PRIMARY AND SECONDARY OUTCOME MEASURES

Smoking exposure was considered at the time of hospital registration. We calculated OR, unadjusted and adjusted for gender, age and alcohol consumption, with 95% CIs.

RESULTS

After adjustment, the risk of developing cancer associated with smoking was very high (piriform sinus, bronchi and lung, larynx, hypopharynx, oropharynx and oral cavity), high (oesophagus and bladder), moderate (anus and anal canal stomach, nasal cavity, middle ear and paranasal sinuses, pancreas, nasopharynx, other parts of the biliary tract and kidney and low (liver, gall)). There was no association between smoking and cancers of the central nervous system and myeloid leukaemia. For thyroid cancer there was a decreased risk of developing the disease. The AF was higher than 50% for hypopharynx, larynx, bronchi and lung, oropharynx, oral cavity and oesophagus cancers.

CONCLUSIONS

This study confirms a high risk of developing cancer of the hypopharynx, bronchi and lung, larynx, oropharynx and oral cavity, oesophagus and bladder cancer among smokers and establishes the AF attributable to smoking in the development of different types of cancer in Brazil.

Tobacco smoking, epilepsy, and seizures

Tobacco smoking is considered the greatest risk factor for death caused by noncommunicable diseases. In contrast to extensive research on the association between tobacco smoking and diseases such as heart attack, stroke, and cancers, studies on the association between tobacco smoking and seizures or epilepsy are insufficient. The exact roles tobacco smoking and nicotine use play in seizures or epilepsy have not been well reviewed. We reviewed available literature and found that 1) there are vast differences between tobacco smoke and nicotine based on their components and their effects on seizures or epilepsy; 2) the seizure risk in acute active tobacco smokers, women who smoke during pregnancy, electronic cigarette smokers, and the role of smoking in sudden unexplained/unexpected death in epilepsy remain unclear; 3) seizure risks are higher in acute secondhand smokers, chronic active smokers, and babies whose mothers smoke; 4) tobacco smoke protects against seizures in animal models whereas nicotine exerts mixed effects in animals; and 5) tobacco smoking agents can be noneffective, proconvulsant, or anticonvulsant. Finally, the opportunities for future research on this topic is discussed.

Impact of cigarette smoking on outcome of hepatocellular carcinoma after surgery in patients with hepatitis B

BACKGROUND AND OBJECTIVES

Cigarette smoking is a potential risk factor for hepatocellular carcinoma (HCC) initiation, partially through interaction with hepatitis B virus (HBV). We examined the hypothesis that cigarette smoking might be associated with HBV-related HCC recurrence and patient survival after curative surgery.

PATIENTS AND METHODS

Data of 302 patients with HBV infection who had undergone curative resection for HCC were prospectively collected from 2008 to 2011. Smoking status and smoking quantity (pack-years, PY) were asked at admission. Factors affecting recurrence-free survival (RFS) were examined. RFS and liver-specific mortality (LSM) stratified by risk factors were compared with log-rank test.

RESULTS

109 were current smokers. Current smokers were not different from non-smokers in tumor burden and surgical procedure. Univariate and multivariate analysis identified that heavy smoking (PY ≥ 20) was the most significant factor associated with HBV-related HCC recurrence after curative surgical resection (p = 0.001), followed by anti-HBV treatment (p<0.01), current smoking (p = 0.028), surgical margin <1 cm (p = 0.048) and blood transfusion >600 ml (p = 0.028). The median RFS in non-smokers, ex-smokers and current smokers was 34 months, 24 months and 26 months, respectively (p = 0.033). Current smokers had significantly worse RFS rate and increased 5-year cumulative LSM than non-smokers (p = 0.024, and p<0.001, respectively). Heavy smokers had significantly worse RFS than non- and light smokers (0

CONCLUSIONS

Smoking history and quantity appears to be risk factors for HBV-related HCC recurrence and LSM of patients after surgery. For smokers, continued smoking postoperatively might accelerate tumor recurrence and patient death. Therefore, smoking abstinence should be strongly recommended to patients pre- and postoperatively.

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MESH Headings

• Carcinoma, Hepatocellular/complications
• Carcinoma, Hepatocellular/physiopathology
• Carcinoma, Hepatocellular/surgery
• Female
• Hepatitis B/complications
• Humans
• Liver Neoplasms/complications
• Liver Neoplasms/physiopathology
• Liver Neoplasms/surgery
• Male
• Middle Aged
• Prognosis
• Recurrence
• Smoking/physiopathology
• Nicotiana

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Grants Collapse

Affiliation(s)

Xu-Feng Zhang Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
Tao Wei Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
Xue-Min Liu Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
Chang Liu Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
Yi Lv Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China

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Factors predicting survival after post-transplant hepatocellular carcinoma recurrence

BACKGROUND

Although factors associated with an increased risk of recurrence after liver transplantation for hepatocellular carcinoma (HCC) have been extensively studied, the history of patients with a post-transplant recurrence is poorly known.

METHODS

Patients experiencing a post-transplant HCC recurrence from 1996 to 2011 in two transplant programs were included. Demographic, transplant, and post-recurrence variables were assessed.

RESULTS

Thirty patients experienced an HCC recurrence-22 men and 8 women with a mean age of 55 ± 6 years. Sixteen (53 %) were outside the Milan criteria at the time of transplantation. Most recurrences (60 %) appeared within the first 18 months after transplantation, ranging between 1.7 and 109 months (median 14.2 months). Mean post-recurrence survival was 33 ± 31 months. On univariate analysis, total tumor volume (TTV; p = 0.047), microvascular invasion (p = 0.011), and time from transplant to recurrence (p = 0.001) predicted post-recurrence survival. On multivariate analysis, both time from transplant to recurrence (p = 0.001) and history of rejection (p = 0.043), but not the location of the recurrence or the type of recurrence treatment, predicted post-recurrence survival.

CONCLUSION

This study suggests that patients with early post-transplant HCC recurrence have worse outcomes. Those with a history of graft rejection have better survivals, possibly due to more active anti-cancer immunity.

Independent and supra-additive effects of alcohol consumption, cigarette smoking, and metabolic syndrome on the elevation of serum liver enzyme levels

We investigated the independent and combined effects of alcohol consumption, cigarette smoking and metabolic syndrome on abnormal liver function, i.e., the elevation of serum liver enzyme levels. Participants of a Korean population-based prospective cohort aged ≥30 years without liver disease, diabetes, or cardiovascular diseases were included. Information on alcohol consumption, smoking status, and metabolic syndrome, defined as per the criteria of the Adult Treatment Panel III, were applied to evaluate their impact on serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyl transferase (GGT). Alcohol consumption, cigarette smoking and metabolic syndrome were the significant individual factors that elevated serum liver enzyme levels. Supra-additive effects of metabolic syndrome and either alcohol consumption or cigarette smoking were also identified. The combination of heavy drinking (≥24 g/day) and metabolic syndrome conferred an effect that was higher than the sum of the two individual effects (Synergic Index (SI): AST, 2.37 [1.20-4.67]; GGT, 1.91 [1.17-3.13]). Only GGT level (odds ratio 6.04 [3.68-9.94], SI 2.33 [1.24-4.41]) was significantly elevated when the effect of moderate drinking (<24 g/day) and metabolic syndrome was combined. The combined effect of any level of alcohol consumption and cigarette smoking was also supra-additive on the elevation of GGT level with SIs of 5.57 for drinking <24 g/day and smoking ≤20 pack years, 5.12 for <24 g/day and >20 pack years, 1.80 for ≥24 g/day and ≤20 pack years, 2.03 for ≥24 g/day and >20 pack years, while only the combined effect of drinking ≥24 g/day and smoking >20 pack years elevated the AST level (SI 4.55 [3.12-6.61]). The combined effect of cigarette smoking and metabolic syndrome was not supra-additive. To prevent fatty liver disease and other related diseases, a multifactorial prevention strategy that includes limited alcohol consumption, smoking cessation and rectification of adverse metabolic profiles is required.

Smoking and risk of liver cirrhosis: a population-based cohort study

OBJECTIVE

Alcohol is the most acknowledged risk factor for liver cirrhosis. Smoking is rarely considered to be a cause of liver cirrhosis even though a few studies have suggested the opposite. The aim of this study was to assess the independent effect of smoking on alcoholic liver cirrhosis and liver cirrhosis in general.

MATERIALS AND METHODS

The authors used data from the Copenhagen City Heart Study including a cohort of 9889 women and 8590 men from the Danish general population. Smoking and covariates were assessed at four consecutive examinations in 1976-78, 1981-83, 1991-94 and 2001-03. Updated measures were used in the analyses. Information on incident cases of alcoholic liver cirrhosis and liver cirrhosis was obtained from national hospital registries. Data were analyzed by means of Cox regression.

RESULTS

A total of 225 cases of alcoholic liver cirrhosis and 431 cases of liver cirrhosis occurred during follow-up. The hazard ratios (HR) of alcoholic liver cirrhosis was 3.9, 95% confidence interval (CI): 1.6, 9.4 for women and 1.6, 95% CI: 0.9, 3.0 for men smoking >10 g of tobacco per day compared with never-smokers. For liver cirrhosis, corresponding HRs were 2.2, 95% CI: 1.4, 3.4 for women and 1.4, 95% CI: 0.9, 2.2 for men. The HRs were adjusted for age, alcohol intake, education and body mass index.

CONCLUSIONS

Smoking was associated with an increased risk of liver cirrhosis independent of alcohol intake.

Genetic polymorphism of the kinesin-like protein KIF1B gene and the risk of hepatocellular carcinoma

Background

Frequent deletions of the kinesin-like protein gene 1B (KIF1B) have been reported in neural tumors. Recently, a genome-wide association study revealed an association between polymorphisms in the KIF1B gene and the risk of hepatocellular carcinoma (HCC), and several case-control studies have further investigated this relationship. However, these studies have yielded controversial results. We therefore performed a meta-analysis to derive a more precise estimation of the association between the KIF1B gene polymorphisms and HCC risk.

Methodology/Principal Finding

PubMed, EMBASE, the ISI Web of Science and the CNKI databases were systematically searched to identify relevant studies. A total of 5 studies containing 13 cohorts with 5,773 cases and 6,404 controls were included. Odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to assess the strength of the associations. Subgroup analyses were conducted based on ethnicities, sample sizes and quality scores. Overall, the G allele at rs17401966 of the KIF1B gene was associated with a significantly decreased risk for HCC (OR  = 0.81, 95%CI: 0.70–0.93; P = 0.003). Furthermore, subgroup analyses showed that the G allele at rs17401966 of the KIF1B gene significantly reduced the risk for HCC in Chinese cohorts (OR  = 0.76, 95%CI: 0.64–0.90; P = 0.002), large-sample-size cohorts (OR  = 0.80, 95%CI: 0.73–0.88, P<0.01) and high-quality cohorts (OR  = 0.78, 95%CI: 0.71–0.87, P<0.01). However, no significant associations were found in small-sample-size cohorts, studies with low-quality scores and when excluding the cohorts from the study reporting the original discovery.

Conclusion/Significance

These findings demonstrate that the presence of the G allele at rs17401966 of the KIF1B gene may decrease the risk for HCC and suggest that KIF1B may play a critical role in the development of HCC. High-quality studies with larger sample sizes and different ethnic populations will be of great value to further confirm these findings.

Diabetes mellitus and risk of hepatocellular carcinoma: findings from the Singapore Chinese Health Study

Background:

The increasing prevalence of diabetes may contribute to the rising incidence of hepatocellular carcinoma (HCC) in the US and other developed countries where HCC incidence is relatively low. Data from prospective studies on diabetes and risk of HCC in at-risk populations due to high prevalence of viral hepatitis in southeast Asia are sparse.

Methods:

The Singapore Chinese Health Study is a prospective cohort of 63 257 middle-aged and older Chinese men and women enrolled in 1993–1998. Besides an in-person interview administered to all participants at baseline, testing of serologic markers of hepatitis B or C infections were performed on a subset of cohort subjects. After a mean follow-up of 14 years, 499 cohort participants developed HCC.

Results:

A history of diabetes at baseline was associated with a hazard ratio of 2.14 (95% confidence interval, 1.69–2.71). This statistically significant association was comparable in magnitude between men and women, and remained equally strong across strata of subjects defined by the number of years between their first clinical diagnosis of diabetes and time of enrolment in this cohort. Within a nested case-control set of cohort subjects tested for serological markers of hepatitis B or C infections, the diabetes–HCC association was found to be present mainly among those devoid of any markers.

Conclusion:

A history of diabetes at baseline is highly associated with non-viral HCC. Future studies are warranted to elucidate the biological mechanism underpinning the role of diabetes in nonviral-related hepatocarcinogenesis.

Roles of alcohol and tobacco exposure in the development of hepatocellular carcinoma

The purpose of this report is to summarize the roles of alcohol and tobacco exposure in the development of hepatocellular carcinoma (HCC). Chronic heavy alcohol exposure is a major risk factor for HCC, which is the most frequent type of liver cancer. Alcohol ingestion may initiate and or promote the development of HCC by: 1) acetaldehyde-DNA adduct formation; 2) cytochrome P4502E1-associated reactive oxygen species (ROS) generation , lipid peroxidation, p53 mutation, and conversion of pro-carcinogens to carcinogens; 3) iron accumulation that leads to ROS generation, lipid peroxidation, p53 mutation, and initiation of inflammatory cascade via nuclear factor-KappaB (NF-kB) activation; 4) glutathione depletion leading to oxidative stress; 5) s-adenosylmethionine (SAM) depletion and associated DNA hypomethylation of oncogenes ; 6) retinoic acid depletion and resultant hepatocyte proliferation via up-regulation of activator protein-1 (AP-1); 7) initiating an inflammatory cascade through increased transfer of endotoxin from intestine to liver, Kupffer cell activation via CD14/toll-like receptor-4 (TLR-4), oxidative stress, NF-kB or early growth response-1(Egr-1) activation, and generation of inflammatory cytokines and chemokines; 8) induction of liver fibrosis; and 9) decreasing the number and/or function of natural killer cells. Tobacco exposure is also a risk factor for HCC. It may contribute to the initiation and promotion of HCC due the presence of mutagenic and carcinogenic compounds as well as by causing oxidative stress due to generation of ROS and depletion of endogenous antioxidants. Simultaneous exposure to alcohol and tobacco is expected to promote the development of HCC in an additive and/or synergistic manner.

Potential for statins in the chemoprevention and management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common, treatment-resistant malignancy with a complex molecular pathogenesis. Statins are a widely used class of cholesterol-lowering drugs with potential anticancer activity. We reviewed the evidence for a role of statins in primary and secondary chemoprevention of HCC and slowing the course of otherwise incurable primary or recurrent disease. A literature search (key words: Statins, hepatocellular carcinoma) conducted to this end, retrieved 119 references. Here we summarize the history, mechanism of action and cardiovascular use of statins and highlight that statins can affect several pathways implicated in the development of HCC. In vitro and animal studies provide strong evidence for a favorable effect of statins on HCC. However, evidence in humans is conflicting. We discuss in full detail the methodological strengths and pitfalls of published data including three cohort studies suggesting that the use of statins may protect from the development of HCC and of a single trial reporting increased survival in those with advanced HCC randomized to receive statins. A remarkably hepato-safe class of drugs acting on both hepatocyte and endothelial cells, statins also have potentially beneficial effects in lowering portal hypertension. In conclusion, there is strong experimental evidence that statins are beneficial in chemopreventing and slowing the growth of HCC. However, randomized controlled trials are necessary in order to investigate the role of statins in the chemoprevention of HCC and in slowing the course of otherwise incurable disease in humans.

Roles of alcohol and tobacco exposure in the development of hepatocellular carcinoma

The purpose of this report is to summarize the roles of alcohol and tobacco exposure in the development of hepatocellular carcinoma (HCC). Chronic heavy alcohol exposure is a major risk factor for HCC, which is the most frequent type of liver cancer. Alcohol ingestion may initiate and or promote the development of HCC by: 1) acetaldehyde-DNA adduct formation; 2) cytochrome P4502E1-associated reactive oxygen species (ROS) generation , lipid peroxidation, p53 mutation, and conversion of pro-carcinogens to carcinogens; 3) iron accumulation that leads to ROS generation, lipid peroxidation, p53 mutation, and initiation of inflammatory cascade via nuclear factor-KappaB (NF-kB) activation; 4) glutathione depletion leading to oxidative stress; 5) s-adenosylmethionine (SAM) depletion and associated DNA hypomethylation of oncogenes ; 6) retinoic acid depletion and resultant hepatocyte proliferation via up-regulation of activator protein-1 (AP-1); 7) initiating an inflammatory cascade through increased transfer of endotoxin from intestine to liver, Kupffer cell activation via CD14/toll-like receptor-4 (TLR-4), oxidative stress, NF-kB or early growth response-1(Egr-1) activation, and generation of inflammatory cytokines and chemokines; 8) induction of liver fibrosis; and 9) decreasing the number and/or function of natural killer cells. Tobacco exposure is also a risk factor for HCC. It may contribute to the initiation and promotion of HCC due the presence of mutagenic and carcinogenic compounds as well as by causing oxidative stress due to generation of ROS and depletion of endogenous antioxidants. Simultaneous exposure to alcohol and tobacco is expected to promote the development of HCC in an additive and/or synergistic manner.