Effect of cytokine genotypes on the hepatitis B virus-hepatocellular carcinoma association

Relationships between tumour necrosis factor-α, interleukin-12B and interleukin-10 gene polymorphisms and hepatitis B in Chinese Han haemodialysis patients

AIM

To investigate the possible association of gene polymorphisms of tumour necrosis factor (TNF)-α (-238 and -308), interleukin (IL)-10 (-592 and -819) and 3' untranslated region (3'UTR) of the IL12B (-1188) and hepatitis B in Chinese Han haemodialysis (HD) patients.

METHODS

The genotyping of TNF-α -238 and -308, IL-10 -592 and -819 and 3'UTR of the IL12B were performed by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method.

RESULTS

The TNF-α-238 A allele, the IL12B 3'UTR C/C, C/A genotypes were associated with decreased susceptibility to hepatitis B viral infection (P = 0.047, P = 0.003 and P = 0.001 respectively). The frequencies of IL-10-592 A/A genotype, IL-10-819 T/T genotype were lower in the HBV persistence group (P = 0.029 and P = 0.019) than those in the virus clearance group.

CONCLUSIONS

TNF-α and IL12B 3'UTR gene polymorphisms may be associated with HBV susceptibility and IL-10 gene polymorphisms may be related to the HBV persistence infection in Chinese Han HD patients.

The interleukin-10-1082 promoter polymorphism and cancer risk: a meta-analysis

Interleukin-10 (IL-10) is a multifunctional cytokine with both immunosuppressive and anti-angiogenic properties and play an important role in the pathogenesis of cancer. IL-10-1082A>G polymorphism is the most extensively studied polymorphism in the IL-10 gene in cancer susceptibility. To date, a number of case-control studies were conducted to investigate the association between IL-10-1082A>G polymorphism and cancer risk in humans. However, the association between the IL-10-1082A>G polymorphism and cancer risk is still ambiguous. In an effort to solve this controversy, we performed a meta-analysis based on 61 case-control studies, including 14,499 cancer cases and 16,967 controls. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. In the stratified analyses by specific cancer type, increased risk was found in lung cancer (OR = 3.16, 95% CI = 1.16-8.63 for GA versus AA; OR = 2.07, 95% CI = 1.16-3.70 for GG versus AA; OR = 3.17, 95% CI = 1.31-7.68 for GA/GG versus AA) and non-Hodgkin's lymphoma (OR = 1.18, 95% CI = 1.02-1.36 for GA versus AA; OR = 1.17, 95% CI = 1.02-1.35 for GA/GG versus AA). The meta-analysis also indicated that the variant genotypes were associated with a moderately increased risk in Asians in all genetic models (OR = 1.80, 95% CI = 1.17-2.76 for GA versus AA; OR = 3.32, 95% CI = 1.62-6.82 for GG versus AA; OR = 1.67, 95% CI = 1.07-2.60 for GA/GG versus AA; OR= 2.93, 95% CI = 1.43-6.03 for GG versus AA/GA). The meta-analysis suggested that the IL-10-1082A>G polymorphism was associated with increased risk of cancer in Asians and lung cancer and non-Hodgkin's lymphoma. To draw comprehensive and true conclusions, more researches with larger numbers of worldwide participants are needed to examine associations between IL-10-1082A>G polymorphism and cancer risk.

Hepatocellular carcinoma and other liver disease among Greenlanders chronically infected with hepatitis B virus: a population-based study

BACKGROUND

In Greenland, the prevalence of hepatitis B surface antigen carriers, reflecting chronic hepatitis B virus (HBV) infection, is 5%-10%. However, the incidence of cirrhosis and hepatocellular carcinoma in this population has been reported to be low. We investigated this discrepancy in a large population-based cohort study.

METHODS

In total, 8879 Greenlanders (16% of the population) were recruited for population-based surveys performed from May 5 to July 7, 1987, and from November 1 to November 21, 1998, with follow-up until March 31, 2010. HBV status was based on serological testing, supplemented by data from all available HBV registries in Greenland to determine changes in HBV status over time. Information on morbidity and mortality was obtained from the Patient Discharge Registry, the Cancer Registry, and the Central Registration System. Sex, age, ethnicity, and period-adjusted incidence rate ratios (IRRs) were estimated using Poisson regression. World standardized rates were derived from these and World Health Organization data.

RESULTS

The 650 chronically HBV-infected persons had higher rates of hepatocellular carcinoma (adjusted IRR = 8.70; 95% CI = 2.06 to 36.7), liver disease (adjusted IRR = 5.73, 95% CI = 3.52 to 9.34), and all-cause mortality (adjusted IRR = 1.47; 95% CI = 1.21 to 1.79) than the 5160 HBV-negative persons. However, the world standardized incidence rates of hepatocellular carcinoma (38.5 cancers per 100 000 person-years) and cirrhosis (24 cases per 100 000 person-years) among chronically HBV-infected persons were low compared with results from population-based studies from countries with low, intermediate, and high rates of endemic HBV infection.

CONCLUSION

The relatively low incidence of hepatocellular carcinoma and other HBV-related morbidity among chronic HBV-infected persons in Greenland suggest a more benign course of HBV among the Greenlandic Inuit than in populations in other parts of the world.

Gene-gene interactions between interleukin-12A and interleukin-12B with the risk of brain tumor

Emerging evidence from preclinical and clinical studies has shown that interleukin-12 (IL-12) has some effectiveness against endogenously arising brain tumor. The aim of this study was to investigate interactions of IL-12A and IL-12B polymorphisms on the risk of brain tumor. We analyzed IL-12A rs2243115 and IL-12B rs3212227 polymorphisms in 170 patients with brain tumor and 222 healthy controls in a Chinese population using a polymerase chain reaction-restriction fragment length polymorphism assay and DNA sequencing method. Individuals carrying a G allele of IL-12A rs2243115 had a significantly higher risk of developing brain tumor compared with those carrying a T allele (odds ratio [OR]=2.01, 95% confidence interval [CI], 1.17-3.45). After stratification analysis according to tumor types, a similarly higher risk was detected in patients with glioma (OR=2.56, 95% CI, 1.25-5.21). When gene-gene interactions were examined, carriers at both loci rs2243115 TG/GG and rs3212227 AC/CC had a 2.62-fold increased risk of glioma compared with those with rs2243115 TT and rs3212227 AC/CC genotypes (OR=2.62, 95% CI, 1.05-6.50). This study provides evidence that IL-12A rs2243115 may be associated with the risk of brain tumor. Additionally, gene-gene interactions of IL-12A rs2243115 and IL-12B rs3212227 may contribute to brain tumor susceptibility.

Development of a Listeria monocytogenes-based vaccine against hepatocellular carcinoma

Live attenuated Listeria monocytogenes (LM) is a promising bacterial vector able to induce a T-cell response to tumor-associated antigens and demonstrates great potential for use in vaccine development. A novel recombinant LM-based vaccine (Lmdd (LM ΔdalΔdat)-MPFG (multiple peptide fusing genes)) was developed with the ability to express and secrete hepatocellular carcinoma (HCC)-related tumor-associated antigens fragments due to the insertion of hepatitis B virus (HBV)-X protein (HBx)-derived epitopes HBx(52-60) and HBx(140-148), the universal T-helper epitope, alpha-fetoprotein (AFP) epitope AFP(158-166), and melanoma antigen gene (MAGE)-3(271-279) into the HBV core protein. Following immunization with the Lmdd-MPFG vaccine, macrophages exhibited uptake of the bacteria; the vaccine was then nearly cleared 3 days after the first administration. It disappeared even more quickly following subsequent vaccinations. However, recombinant Lmdd-MPFG allowed for the full development of an antitumor response towards the human leukocyte antigen (HLA)-A0201 epitopes of MPFG. Each epitope stimulated an augmented T-cell proliferation and enhanced the supernatant level of interferon (IFN)-γ in vitro. In addition, IFN-γ-producing CD8(+) T cells as well as in vivo cytolytic activity were significantly increased in HLA-A2 transgenic mice. Additionally, the Lmdd-MPFG developed a strong antitumor response, as indicated by the significant resistance of immunized mice to MPFG-positive Hepa1-6 cell challenge in both a prophylactic and therapeutic setting. Tumor regression was accompanied by an enhanced cytotoxic T lymphocyte response and a decrease of regulatory T cells in the tumor. Collectively, these results suggest that utilizing attenuated LM as a vaccine vector, able to carry the MPFG gene, presents a potentially feasible strategy for prevention of HCC.

Interleukin-10 gene polymorphisms and hepatocellular carcinoma susceptibility: A meta-analysis

AIM: To assess the association between Interleukin-10 (IL-10) gene IL-10-1082 (G/A), IL-10-592(C/A), IL-10-819 (T/C) polymorphisms and hepatocellular carcinoma (HCC) susceptibility.

METHODS: Two investigators independently searched the Medline, Embase, China National Knowledge Infrastructure, and Chinese Biomedicine Database. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) for IL-10 polymorphisms and HCC were calculated in a fixed-effects model (the Mantel-Haenszel method) and a random-effects model (the DerSimonian and Laird method) when appropriate.

RESULTS: This meta-analysis included seven eligible studies, which included 1012 HCC cases and 2308 controls. Overall, IL-10-1082 G/A polymorphism was not associated with the risk of HCC (AA vs AG + GG, OR = 1.11, 95% CI = 0.90-1.37). When stratifying for ethnicity, the results were similar (Asian, OR = 1.12, 95% CI = 0.87-1.44; non-Asian, OR = 1.10, 95% CI = 0.75-1.60). In the overall analysis, the IL-10 polymorphism at position -592 (C/A) was identified as a genetic risk factor for HCC among Asians; patients carrying the IL-10-592*C allele had an increased risk of HCC (OR = 1.29, 95% CI = 1.12-1.49). No association was observed between the IL-10-819 T/C polymorphism and HCC susceptibility (TT vs TC + CC, OR = 1.02, 95% CI = 0.79-1.32).

CONCLUSION: This meta-analysis suggests that IL-10-592 A/C polymorphism may be associated with HCC among Asians. IL-10-1082 G/A and IL-10-819 T/C polymorphisms were not detected to be related to the risk for HCC.

Aromatase (CYP19) promoter gene polymorphism and risk of nonviral hepatitis-related hepatocellular carcinoma

BACKGROUND

Experimental studies suggest that sex hormones may induce or promote the development of hepatocellular carcinoma (HCC). Androgens are converted to estrogens by the CYP19 gene product, aromatase. Hepatic aromatase level and activity have been shown to be markedly elevated in HCC. Aromatase expression in liver tumors is driven by a promoter upstream of CYP19 exon I.6.

METHODS

First, the authors identified an A/C polymorphism in the exon I.6 promoter of the CYP19 gene. To determine whether allelic variants in the CYP19 I.6 promoter differ in their ability to drive gene expression, we carried out an in vitro reporter gene assay. Then, the authors studied the association between this polymorphism and HCC risk in 2 complementary case-control studies: 1 in high-risk southern Guangxi, China, and another in low-risk US non-Asians of Los Angeles County.

RESULTS

Transcriptional activity was 60% higher for promoter vectors carrying the rs10459592 C allele compared with those carrying an A allele (P = .007). In both study populations, among subjects negative for at-risk serologic markers of hepatitis B or C, there was a dose-dependent association between number of high activity C allele and risk of HCC (P(trend) = .014). Risk of HCC was significantly higher (odds ratio [OR], 2.25; 95% confidence interval (CI), 1.18-4.31) in subjects homozygous for the C allele compared with those homozygous for the A allele.

CONCLUSIONS

This study provides epidemiologic evidence for the role of hepatic aromatization of androgen into estrogen in the development of nonviral hepatitis-related HCC.

Coffee consumption and reduced risk of hepatocellular carcinoma: findings from the Singapore Chinese Health Study

BACKGROUND

Coffee consumption has been associated with reduced markers of hepatic cell damage, reduced risk of chronic liver disease, and cirrhosis across a variety of populations. Data on the association between coffee consumption and risk of hepatocellular carcinoma (HCC), especially in high-risk populations, are sparse.

METHODS

This study examines the relationship between coffee and caffeine consumption, and the risk of developing HCC within the Singapore Chinese Health Study, a prospective cohort of 63,257 middle-aged and older Chinese men and women, a relatively high-risk population for HCC. Baseline data on coffee consumption and other dietary and lifestyle factors were collected through in-person interviews at enrollment between 1993 and 1998.

RESULTS

As of 31 December 2006, 362 cohort participants had developed HCC. High levels of coffee or caffeine consumption were associated with reduced risk of HCC (p for trend < 0.05). Compared with non-drinkers of coffee, individuals who consumed three or more cups of coffee per day experienced a statistically significant 44% reduction in risk of HCC (hazard ratio 0.56, 95% confidence interval, 0.31-1.00, p = .049) after adjustment for potential confounders and tea consumption.

CONCLUSION

These data suggest that coffee consumption may reduce the risk of developing HCC in Chinese in Singapore.

Non-association of IL-12 +1188 and IFN-γ +874 polymorphisms with cytokines serum level in occult HBV infected patients

BACKGROUND/AIM

Occult hepatitis B infection (OBI) is identified as a form of hepatitis in which despite the absence of detectable HBsAg, HBV-DNA is observed in peripheral blood of patients. The main aim of this study has been to investigate the association between polymorphisms in +874 of IFN-γ and +1188 of IL-12 with their serum level in patients suffering from OBI.

MATERIALS AND METHODS

In this experimental study, plasma samples of 3700 blood donors were tested for the presence of hepatitis B surface antigen (HBsAg) and anti-HBc by ELISA. The HBsAg-/anti-HBc+ samples were selected and screened for HBV-DNA by PCR. HBV-DNA positive samples were assigned as OBI cases and ARMS-PCR techniques were performed to examine the two known polymorphisms within IL-12 and IFN-γ. In addition, the serum levels of IL-12 and IFN-γ were also determined by ELISA.

RESULTS

Results of this study demonstrated that, 352 (9.5%) out of 3700 blood samples were HBsAg-/anti-HBc+ and HBV-DNA was detected in 57/352 (16.1%) of HBsAg-/anti-HBc+ samples. Our results showed that groups showed significant difference in CC allele of +1188 region of IL-12 and no difference was observed in the other evaluated genes. Our results also showed that the alleles of +1188 region of IL-12 and alleles of +874 of IFN-γ were also not associated with serum level of cytokines.

CONCLUSION

According to the results of this study, it may be concluded that the polymorphisms in +1188 region of IL-12 and +874 region of IFN-γ would not affect the expression of both cytokines at serum level in OBI patients.

The TNF-α, IL-1B and IL-10 polymorphisms and risk for hepatocellular carcinoma: a meta-analysis

OBJECTIVE

TNF-α-308 G/A, TNF-α-238 G/A, IL-1B-31 T/C, IL-1B-511 C/T, and IL-10-1082 G/A polymorphisms have been reported to influence the risk for hepatocellular carcinoma (HCC) in many studies; however, the results still remains controversial and ambiguous. The aim of this study was to determine more precise estimations for the relationship between TNF-α, IL-1B, and IL-10 polymorphisms and the risk for HCC by meta-analysis.

METHODS

Electronic searches for all publications were conducted on associations between these variants and HCC in several databases through September 2010. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated to estimate the strength of this association in a random-effect model. Twenty studies were identified, involving 2,763 HCC patients and 4,152 controls.

RESULTS

This meta-analysis showed significant association between TNF-α-308 polymorphism and HCC (AA + GA vs. GG: OR = 1.74, 95% CI = 1.12-2.72). In Caucasian and Asian subgroups, OR values (95% CI) were 1.49 (0.58-3.82) and 1.84 (1.06-3.20), respectively. While the ORs for TNF-α-238 G/A, IL-1B-31 T/C, -511 C/T and IL-10-1082 G/A polymorphisms and HCC were 1.37 (0.95-2.00), 1.24 (0.99-1.55), 1.12 (0.66-1.88) and 0.91 (0.74-1.12), respectively. The sensitivity analysis further strengthened the overall strong positive correlations. No publication bias was observed in this study.

CONCLUSIONS

TNF-α-308 G/A polymorphism is assumed to confer a higher risk for HCC, especially in Asian population. TNF-α-238 G/A, IL-1B-31 T/C, -511 C/T, and IL-10-1082 G/A polymorphisms were not detected to be related to the risk for HCC.

IL12 polymorphisms, HBV infection and risk of hepatocellular carcinoma in a high-risk Chinese population

To investigate the association between the potentially functional polymorphisms in IL12A and IL12B, HBV infection and risk of hepatocellular carcinoma in a Chinese population, we genotyped three polymorphisms, rs568408 (3'UTR G>A), rs2243115 (5'UTR T>G) in IL12A and rs3212227 (3'UTR A>C) in IL12B in a case-control study of 869 hepatocellular carcinoma (HCC) cases and 891 cancer-free controls. We found that the IL12A rs568408 GA/AA variant genotypes were associated with a significantly increased risk of HCC (adjusted odds ratio (OR) = 1.53, 95% confidence interval (CI) = 1.17-2.00), compared with the wild-type GG homozygote. In the stratified analyses, the increased risk of HCC associated with rs568408 GA/AA was more evident in patients who were negative for HBsAg (adjusted OR = 1.71, 95% CI = 1.23-2.39). However, no significant associations between IL12A rs2243115 T/G, IL12B rs3212227 A/C and risk of HCC were observed. Our findings indicate that IL12A rs568408 may contribute to the risk of HCC and modify HCC risk associated with HBV infection.

Genetic polymorphisms in the cytokine genes and risk of hepatocellular carcinoma in low-risk non-Asians of USA

Polymorphisms in cytokine genes responsible for inflammatory and immune responses are associated with risk of hepatocellular carcinoma (HCC) in high-risk Chinese population. Similar data in low-risk populations are lacking. A population-based case-control study of HCC was conducted including 120 HCC patients and 230 matched control subjects of non-Asian residents in Los Angeles County, California. Genetic variants in the interferon gamma (IFNgamma), tumor necrosis factor-alpha (TNFalpha), interleukin-2 (IL-2), IL-4, IL-6, IL-10, IL-12 and IL-18 genes were determined by Taqman assays. The logistic regression method was used to analyze the data. For T helper (Th) 1 genes (IFNgamma, IL-6 and IL-12), relative to the putative high-activity genotypes, individual low-activity genotypes were associated with statistically non-significant increases in HCC risk. The odds ratio (OR) was 1.53 [95% confidence interval (CI) = 0.53-4.39] for three versus zero low-activity genotypes. For Th2 cytokines (IL-4 and IL-10), low- versus high-activity genotypes were associated with statistically non-significant decreases in HCC risk. The OR was 0.64 (95% CI = 0.27-1.55) for two versus zero low-activity genotypes. When the Th1 and Th2 genotypes were examined simultaneously, the highest level of risk was observed in individuals jointly possessing the highest number of low-activity Th1 genotypes and the lowest number of low-activity Th2 genotypes. There was a roughly doubling of risk between these two extreme genetic profiles, which did not reach statistical significance (OR = 1.98, 95% CI = 0.50-7.84, P = 0.08). In contrast to high-risk Chinese, Th1 and Th2 genotypes did not impact in a major way on risk of HCC in USA non-Asians.

Prospective evaluation of hepatitis B 1762(T)/1764(A) mutations on hepatocellular carcinoma development in Shanghai, China

Chronic infection with the hepatitis B virus (HBV) is the most important risk factor for hepatocellular carcinoma (HCC). However, determinants of HCC risk in infected individuals are not well understood. We prospectively evaluated the association between acquired HBV 1762(T)/1764(A) double mutations and HCC risk among 49 incident HCC cases and 97 controls with seropositive hepatitis B surface antigen at baseline from a cohort of 18,244 men in Shanghai, China, enrolled during 1986 to 1989. Compared with HBV carriers without the mutations, chronic HBV carriers with the HBV 1762(T)/1764(A) double mutations experienced an elevated risk of HCC (odds ratio, 2.47; 95% confidence interval, 1.04-5.85; P = 0.04). Risk increased with increasing copies of the double mutations; men with > or =500 copies/microL serum had an odds ratio of 14.57 (95% confidence interval, 2.41-87.98) relative to those without the double mutations (P(trend) = 0.004). Thus, the HBV 1762(T)/1764(A) double mutation is a codeterminant of HCC risk for people chronically infected with HBV.

Alcohol, cofactors and the genetics of hepatocellular carcinoma

Heavy alcohol consumption, chronic infection with the hepatitis B virus (HBV) or the hepatitis C virus (HCV), tobacco smoking, and diabetes are risk factors for hepatocellular carcinoma (HCC). In the Los Angeles Non-Asian HCC Study, heavy alcohol intake was shown to exhibit synergistic effects with viral hepatitis (HBV, HCV) and diabetes in the causation of HCC among individuals with joint exposures. Although chronic infection with HBV is recognized as the most important causal factor for HCC in humans, only a minority of HBV carriers eventually develop HCC, suggesting the presence of important cofactors in HBV-related HCC. In the Guangxi/China HCC Study, a 20-fold difference in HCC risk was observed between individuals possessing the least versus the most favorable cytokine genotypes for hepatitis B viral clearance. Experimental studies have indicated an important role for one-carbon metabolism in HCC development. In both the Los Angeles and Guangxi studies, low-activity genotypes (reduced enzymatic activities) of methylenetetrahydrofolate reductase (MTHFR) and high-activity genotypes (enhanced enzymatic activities) of thymidylate synthase (TYMS), both of which discourage the misincorporation of uracil into DNA, were shown to be associated with a reduced risk for HCC.

Interleukin-2, interleukin-12, and interferon-gamma levels and risk of young adult Hodgkin lymphoma

Young adult Hodgkin lymphoma (YAHL) is associated clinically with altered immunity, including a systemic defect in cell-mediated responses. There is strong evidence of a genetic contribution to risk, so we hypothesized that heritable alterations in cytokine production associated with Th1 function may contribute to susceptibility. We identified twin pairs in whom at least one member had YAHL and measured interleukin-2 (IL-2), interleukin-12 (IL-12), and interferon-gamma (IFN-gamma) levels in PHA-stimulated peripheral blood mononuclear cell supernatant in 90 case-twins, 84 of their disease-free twins (unaffected cotwins), and 90 matched controls. Mean difference and mean percentage difference in cytokine levels between case-twins and controls, and unaffected cotwins and controls were determined using analysis of covariance. YAHL case-twins and their unaffected cotwins had IL-12 levels that were 60.6% (P=.002) and 49% (P=.04) lower than those of their matched controls, respectively. IL-2 levels were significantly higher in case-twins (P=.049), but not unaffected cotwins (P=.57), compared with controls. Differences in IFN-gamma levels were not statistically significant in either comparison. An IL-12 polymorphism known to regulate expression was associated with a 2.8-fold (P=.03) increase in YAHL risk. Thus, both case-twins and their unaffected cotwins had a decreased ability to produce IL-12, which may contribute to YAHL susceptibility.

Genetic polymorphisms in the methylenetetrahydrofolate reductase and thymidylate synthase genes and risk of hepatocellular carcinoma

Methylenetetrahydrofolate reductase (MTHFR) and thymidylate synthase (TYMS) are known to play a role in DNA methylation, synthesis, and repair. The genetic mutations in MTHFR and TYMS genes may have influences on their respective enzyme activities. Data on the association studies of the MTHFR and TYMS genetic polymorphisms and risk of hepatocellular carcinoma (HCC) are sparse. MTHFR and TYMS genotypes were determined on 365 HCC cases and 457 healthy control subjects among Hispanic and non-Hispanic whites and African-Americans in Los Angeles County, California, and among Chinese in the city of Nanning, Guangxi, China. Relative to the high-activity genotype, each low-activity genotype of MTHFR was associated with a statistically nonsignificant 30% to 50% reduction in risk of HCC. Relative to the TYMS3'UTR +6/+6 genotype, individuals with 1 or 2 copies of the deletion allele had a statistically significant 50% reduction in risk of HCC. When we examined HCC risk by the total number of mutant alleles in the 3 polymorphic loci of MTHFR/TYMS (range, 0-4), there was a monotonic decrease in risk with increasing number of mutant alleles (P for trend = 0.003). Individuals possessing the maximum number of mutant alleles (i.e., 4) had an odds ratio of 0.46 (95% confidence interval = 0.23-0.93) for HCC compared with those with no or only 1 mutant allele.

CONCLUSION

This study supports the hypothesis that reduced MTHFR activity and enhanced TYMS activity, both of which are essential elements in minimizing uracil misincorporation into DNA, may protect against the development of HCC.

Genetic polymorphisms in anti-inflammatory cytokine signaling and the prevalence of gastric precancerous lesions in Venezuela

OBJECTIVES

The aim of the study was to assess the effects of genetic polymorphisms in anti-inflammatory mediators, i.e., IL10, IL4 and IL4R on the prevalence of gastric precancerous lesions and their interactions with other environmental factors.

METHODS

The study population consisted of 2,033 Venezuelan subjects known to have extremely high Helicobacter Pylori (HP) infection rates. The odds ratios (OR) and 95% confidence intervals (CI) associated with these polymorphisms were estimated by multinominal logistic regression models for gastric precursor lesions.

RESULTS

We found a 60% increase in risk of intestinal metaplasia (IM) and dysplasia combined (OR 1.62, 95% CI: 1.10-2.38) among the carriers of the IL10-1082 low activity allele. This increased risk was more pronounced for dysplasia than for IM. On the other hand, homozygotes with the low activity allele of the A398G polymorphism in the IL4R gene had a modest increase in risk of atrophic gastritis (OR = 1.52, 95% CI: 1.05-2.21), compared with homozygotes of the high activity allele. There were no statistically significant synergetic interactions between these polymorphisms and environmental risk factors (low fruit intake, high starchy vegetable intake and cigarette smoking) for these lesions.

CONCLUSION

While the results of the present study suggest roles of genetic variability in these anti-inflammatory mediators in different stages of gastric carcinogenesis, there is high likelihood that they were chance findings due to multiple comparisons.

The role of cytokines in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a frequent malignancy worldwide with a high rate of metastasis. The hepatitis B and C viruses are considered major etiological factors associated with the development of HCC, particularly as a result of their induction of chronic inflammation. There is increasing evidence that the inflammatory process is inherently associated with many different cancer types, including HCC. Specifically, this review aims to cover evidence for the potential roles of cytokines, an important component of the immune system, in promoting HCC carcinogenesis and progression. A global summary of cytokine levels, functions, polymorphisms, and therapies with regard to HCC is presented. In particular, the role of proinflammatory Th1 and anti-inflammatory Th2 cytokine imbalances in the microenvironment of HCC patients with metastasis and the possible clinical significance of these findings are addressed. Overall, multiple studies, spanning many decades, have begun to elucidate the important role of cytokines in HCC.

Separate origins of hepatitis B virus surface antigen-negative foci and hepatocellular carcinomas in transgenic HBsAg (alb/psx) mice

We have examined the development and transgene expression in liver lesions of transgenic mice bearing the hepatitis B surface antigen (HBsAg) gene of hepatitis B virus under the control of the albumin promoter (alb/psx) to study liver regeneration and hepatocellular carcinoma (HCC) associated with hepatitis B virus infection. Storage of the HBsAg in the endoplasmic reticulum precedes loss of liver cells and regenerative hyperplastic nodules that do not express HBsAg. Histological analysis indicated that HBsAg-negative foci and nodules arose from liver progenitor cells in the portal zone and lacked mRNA expression. Genomic DNA from eight of nine HBsAg-negative laser capture-excised liver foci showed loss of part of the alb/psx gene, whereas no loss of the actin gene was observed. The alb/psx DNA was intact in adjacent HBsAg-positive tissue. Sequencing of polymerase chain reaction products suggested that alterations in the HBsAg transgene in HBsAg-negative foci occurred via large-scale deletions as opposed to single-site mutations. Southern blot analysis of HCC from 2-year-old transgenic HBsAg mice, however, revealed an intact alb/psx gene. Thus, HBsAg-negative progenitor cells with deletions in the transgene appear to be responsible for compensatory regeneration of the liver, whereas HCCs arise from clonal expansion of hepatocytes with intact alb/psx transgenes.

Interleukin gene polymorphisms and breast cancer: a case control study and systematic literature review

BACKGROUND

Interleukins and cytokines play an important role in the pathogenesis of many solid cancers. Several single nucleotide polymorphisms (SNPs) identified in cytokine genes are thought to influence the expression or function of these proteins and many have been evaluated for their role in inflammatory disease and cancer predisposition. The aim of this study was to evaluate any role of specific SNPs in the interleukin genes IL1A, IL1B, IL1RN, IL4R, IL6 and IL10 in predisposition to breast cancer susceptibility and severity.

METHODS

Candidate single nucleotide polymorphisms (SNPs) in key cytokine genes were genotyped in breast cancer patients and in appropriate healthy volunteers who were similar in age, race and sex. Genotyping was performed using a high throughput allelic discrimination method. Data on clinico-pathological details and survival were collected. A systematic review of Medline English literature was done to retrieve previous studies of these polymorphisms in breast cancer.

RESULTS

None of the polymorphisms studied showed any overall predisposition to breast cancer susceptibility, severity or to time to death or occurrence of distant metastases. The results of the systematic review are summarised.

CONCLUSION

Polymorphisms within key interleukin genes (IL1A, IL1B, IL1RN, IL4R, IL6 and IL10 do not appear to play a significant overall role in breast cancer susceptibility or severity.

Prediagnostic level of serum retinol in relation to reduced risk of hepatocellular carcinoma

BACKGROUND

Retinol and its derivatives (retinoids), which have antioxidant activity and promote cell differentiation, may protect against the development of hepatocellular carcinoma (HCC) by controlling hepatocellular differentiation and reducing inflammatory responses.

METHODS

We examined prospectively the relationship between prediagnostic serum concentrations of retinol, alpha-carotene; beta-carotene; beta-cryptoxanthin; lutein; lycopene; zeaxanthin; alpha-, gamma-, and delta-tocopherols; and selenium and the risk of developing HCC among 213 patients with HCC and 1087 matched control subjects from a cohort of 18,244 men in Shanghai, China, who were monitored from 1986 through 2001. Odds ratios (ORs) and 95% confidence intervals (CIs) for men by quartile of serum concentrations of micronutrients were estimated by using logistic regression with adjustment for cigarette smoking status, alcohol intake, self-reported history of physician-diagnosed hepatitis or liver cirrhosis at recruitment, and seropositivity for hepatitis B surface antigen (HBsAg). All statistical tests were two-sided.

RESULTS

Men with high prediagnostic serum retinol levels had a lower risk of HCC than men in the lowest quartile (Q2 versus Q1, OR = 0.37, 95% CI = 0.22 to 0.61; Q3 versus Q1, OR = 0.30, 95% CI = 0.17 to 0.50; and Q4 versus Q1, OR = 0.13, 95% CI = 0.06 to 0.26; Ptrend < .001). A statistically significant interaction was observed between retinol and HBsAg seropositivity on HCC risk; HBsAg-positive men in the lowest tertile of retinol had a greater than 70-fold higher risk (OR = 72.7, 95% CI = 31.6 to 167.4) of HCC than HBsAg-negative men in the highest tertile of retinol (Pinteraction = .018). No independent effect of serum levels of alpha-carotene; beta-carotene; beta-cryptoxanthin; lutein; lycopene; zeaxanthin; alpha-, gamma-, and delta-tocopherols; or selenium on HCC risk were observed.

CONCLUSION

High prediagnostic serum level of retinol is associated with a decreased risk of HCC in this population.

Interleukin-1β gene polymorphism associated with hepatocellular carcinoma in hepatitis B virus infection

AIM: To examine the effect of interleukin-1-beta (IL-1β) promoter region C-511T and IL-1 receptor antagonist (IL-1RN) polymorphism among the patients with chronic hepatitis B virus (HBV) infection (HCC and non-HCC).

METHODS: Genomic DNA from 136 Thai patients with chronic HBV infection (HCC = 46 and non-HCC = 90) and 152 healthy individuals was genotyped for IL-1β gene polymorphism (-511) using polymerase chain reaction with sequence specific primers (PCR-SSP). The variable number of tandem repeats (VNTR) of IL-1RN gene was assessed by a PCR-based assay. The association between these genes and status of the disease was evaluated by χ² test.

RESULTS: IL-1B-511 genotype C/C was found to be significantly different in patients with HCC when compared with healthy individuals (P  = 0.036, OR = 2.29, 95%CI = 1.05-4.97) and patients without HCC (P =0.036, OR = 2.52, 95%CI=1.05-6.04). Analysis of allele frequencies of IL-1B-511 showed that IL-1B-511 C allele was also significantly increased in patients with HCC, compared to that in healthy control (P  = 0.033, OR = 1.72, 95%CI=1.04-2.84). However, no significant association in IL-1RN gene was found between the two groups.

CONCLUSION: IL-1B-511C allele, which may be associated with high IL-1B production in the liver, is a genetic marker for the development of HCC in chronic hepatitis B patients in Thai population.