TGF-beta1 genotypes in cirrhosis: relationship with the occurrence of liver cancer

Association of TGF-β1 Polymorphism and TGF-β1 Levels With Chronic Hepatitis C and Cirrhosis: A Systematic Review and Meta-Analysis

Despite the extensive research conducted on the relationship between transforming growth factor-beta 1 (TGF-β1) polymorphisms and levels and the onset and development of liver disease, there are still certain gaps that need to be addressed. To address these gaps and provide a comprehensive overview of the current knowledge, this review aimed to identify relevant published research on TGF-β1/TGF-β1 polymorphism, TGF-β1/TGF-β1 levels, and their associations with cirrhosis and hepatitis C. The synthesis of available data was performed to further enhance our understanding in this area. Adopting the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, a search strategy was implemented across several online databases to search for relevant articles as per the defined selection criterion. Eight studies were selected after the completion of the search strategy. Of the eight studies, five revealed a considerably high level of TGF-β1 in patients who had hepatitis C virus (HCV) and liver cirrhosis caused by hepatocellular carcinoma (HCC). The forest plot analysis showed a statistically significant impact of TGF-β1 polymorphism and levels on the incidence of hepatic cirrhosis and hepatitis C, with an odds ratio (OR) of 0.65 and a risk ratio (RR) of 0.76. The heterogeneity test showed a high level of heterogeneity at 94% and 95% for OR and RR, respectively, but the overall effect was significant with P < 0.01 for both measures. According to the results obtained, the authors concluded that TGF-β1 polymorphism and its associated levels should be taken into account while developing preventive and therapeutic approaches for hepatic cirrhosis and hepatitis C.

Gene polymorphisms of inflammatory factors in liver cirrhosis

Introduction: Studies on the association between gene polymorphisms of various inflammatory factors and liver cirrhosis have been inconsistent. The purpose of this study was to comprehensively summarize the available evidence on the association between gene polymorphisms of inflammatory factors and liver cirrhosis through a systematic review. Methods: We searched databases of PubMed, EMBASE, Web of Science, and the Cochrane Library for relevant articles published from building databases to 25 September 2022. A systematic review and meta-analysis were performed to investigate the association between gene polymorphisms of various inflammatory factors and liver cirrhosis. Odds ratios (OR) and 95% confidence intervals (CI) were used to assess the strength of association. Results: A total of 43 articles were included in the systematic review and of them, 22 articles were included in the meta-analysis. The gene polymorphisms of IL-10-1082 GA + AA vs. GG (OR = 1.43, 95% CI = 1.12-1.83), IL-10-1082 AA vs. GG (OR = 2.03, 95% CI = 1.36-3.02), IL-18 -137 GG vs. CC (OR = 3.84, 95% CI = 1.29-11.40), TGF-β1 -509 T vs. C (OR = 2.52, 95% CI = 1.42-4.48), and IFN-γ +874 T vs. A (OR = 1.98, 95% CI = 1.32-2.98) were associated with liver cirrhosis significantly and no association was observed in other gene polymorphisms included in the meta-analysis. The review of inflammatory factors gene polymorphisms that were only reported by a single study indicated 19 gene polymorphisms were risk factors and 4 gene polymorphisms were protective factors for liver cirrhosis, while the association between other 27 gene polymorphisms and liver cirrhosis were not statistically significant. Discussion: This study suggests that IL-10 -1082G/A, IL-18 -137G/C, TGF-β1 -509T/C, and IFN-γ +874T/A were potentially associated with the risk of liver cirrhosis susceptibility. These findings may provide comprehensive evidence for genetic susceptibility and immunogenetic pathology of liver cirrhosis.

TGF-β1 rs1800469 gene polymorphism in the development of cirrhosis & hepatocellular carcinoma in Pakistani HCV patients

Hepatocellular carcinoma (HCC) has been increasing among Pakistani males. Aim: The main objective of this study was to evaluate the role of TGF-β-1 gene polymorphism as a risk factor in chronic hepatitis C virus (HCV) infected HCC patients in Pakistan. Patients & methods: A total of 286 subjects were recruited into three different groups (Group I: 96 healthy controls, Group II: 96 HCV, Group III: 94 HCC). Results: A significant increase in genotype and allele frequencies of TGF-β-1 gene was observed in HCC, HCV with OR = 1.9; 95% CI: 1.275–2.871; p > 0.05, OR = 1.6; 95% CI: 1.12–2.51; p > 0.05 and OR = 1.7; 95% CI: 1.036–1.923; p > 0.05. Conclusion: A higher frequency of the TT genotype and T allele of the TGF-β-1 gene is observed in Pakistani HCV and HCC patients.

Association between host TNF-α, TGF-β1, p53 polymorphisms, HBV X gene mutation, HBV viral load and the progression of HBV-associated chronic liver disease in Indonesian patients

In developing countries, including Indonesia, there is a high mortality rate associated with the progression of hepatitis B virus (HBV)-associated chronic liver disease (CLD). The pathogenesis of HBV infection is influenced by viral and host factors. To determine potential associations between these factors, host single nucleotide polymorphisms (SNPs) on TNF-α, TGF-β1 and p53, HBV X gene mutation and HBV viral load were investigated in patients with HBV-associated CLD in Surabaya, Indonesia. Sera were collected from 87 CLD patients with HBV infection. TNF-α, TGF-β1 and p53 SNPs were genotyped by PCR restriction fragment length polymorphism. The HBV X gene was sequenced and compared with reference strains to determine mutations and the viral load was measured using reverse transcription-quantitative PCR. In Indonesian patients, no association between TNF-α, TGF-β1 and p53 SNPs and CLD or X gene mutation were identified. A total of 23% (20/87) of samples had HBV X gene mutations, including ten substitution types, one deletion and one insertion. Multinomial regression analysis revealed that the K130M/V131I mutations were correlated with CLD progression (OR, 7.629; 95% CI, 1.578-36.884). Significant differences in viral load were found in HBV-infected patients who had X gene mutations, such as R87W/G, I127L/T/N/S and K130M/V131I mutations (P<0.05). The presence of K130M and V131I mutations may be predictive for the progression of HBV-associated CLD in Indonesia.

HBV and HIV/HBV Infected Patients Have Distinct Immune Exhaustion and Apoptotic Serum Biomarker Profiles

Background:

Hepatitis B virus (HBV) infection is a leading cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma worldwide. Due to their shared routes of transmission, approximately 10% of HIV-infected patients worldwide are chronically coinfected with HBV. Additionally, liver disease has become a major cause of morbidity and mortality in HBV/HIV coinfected patients due to prolonged survival with the success of antiretroviral therapy. The relationship between immune exhaustion markers (PD-1/PD-L1) and apoptotic markers such as Fas/FasL, TGFβ1, TNF-α, and Th1/Th2 cytokines are not clearly delineated in HBV/HIV coinfection.

Methods:

Levels of soluble Fas/FasL, TGFβ1, TNF-α, and sPD-1/sPD-L1 as well as Th1 and Th2 cytokines were evaluated in the sera of HBV-monoinfected (n = 30) and HBV/HIV-coinfected (n = 15) patients and compared to levels in healthy controls (n = 20).

Results:

HBV-monoinfected patients had significantly lower levels of the anti-inflammatory cytokine IL-4 (P < 0.05) and higher levels of apoptotic markers sFas, sFasL, and TGFβ-1 (P < 0.001) compared to healthy controls. Coinfection with HIV was associated with higher levels of sFas, TNF-α, and sPD-L1 (P < 0.005), and higher levels of the pro-inflammatory cytokines IL-6, IL-8, and IL-12p70 (P < 0.05) compared to healthy controls. Patients with HBV infection had a unique biomarker clustering profile comprised of IFN-γ, IL12p70, IL-10, IL-6, and TNF-α that was distinct from the profile of the healthy controls, and the unique HIV/HBV profile comprised GM-CSF, IL-4, IL-2, IFN-γ, IL12p70, IL-7, IL-10, and IL-1β. In HBV monoinfection a significant correlation between sFasL and PD1(r = 0.46, P = < 0.05) and between sFas and PDL1 (r = 0.48, P = <0.01) was observed.

Conclusion:

HBV-infected and HBV/HIV-coinfected patients have unique apoptosis and inflammatory biomarker profiles that distinguish them from each other and healthy controls. The utilization of those unique biomarker profiles for monitoring disease progression or identifying individuals who may benefit from novel immunotherapies such as anti-PD-L1 or anti-PD-1 checkpoint inhibitors appears promising and warrants further investigation.

Enhanced circulating transforming growth factor beta 1 is causally associated with an increased risk of hepatocellular carcinoma: a mendelian randomization meta-analysis

The aim of this study was to test the causal association between circulating transforming growth factor beta 1 (protein: TGF-β1 and coding gene: TGFB1) and hepatocellular carcinoma by choosing TGFB1 gene C-509T polymorphism as an instrument in a Mendelian randomization (MR) meta-analysis. Ten English articles were identified for analysis. Two authors independently assessed each article and abstracted relevant data. Odds ratio (OR) and weighted mean difference (WMD) with 95% confidence interval (CI) were synthesized under a random-effects model. Overall, the association of C-509T polymorphism with hepatocellular carcinoma was negative, but its association with circulating TGF-β1 was statistically significant, with a higher concentration observed in carriers of the -509TT genotype (WMD, 95% CI, P: 1.72, 0.67–2.78, 0.001) and -509TT/-509TC genotypes (WMD, 95% CI, P: 0.98, 0.43–1.53, < 0.001). In subgroup analysis, C-509T polymorphism was significantly associated with hepatocellular carcinoma in population-based studies under homozygous-genotype (OR, 95% CI, P: 1.74, 1.08–2.80, 0.023) and dominant (OR, 95% CI, P: 1.48, 1.01–2.17, 0.047) models. Further MR analysis indicated that per unit increase in circulating TGF-β1 was significantly associated with a 38% (95% CI: 1.03–4.65) and 49% (95% CI: 1.01–6.06) increased risk of hepatocellular carcinoma under homozygous-genotype and dominant models, respectively. Conclusively, based on a MR meta-analysis, our findings suggest that enhanced circulating TGF-β1 is causally associated with an increased risk of hepatocellular carcinoma.

Transforming growth factor-β1 gene polymorphisms with liver cirrhosis risk: A meta-analysis

Although several epidemiological studies have investigated the association of transforming growth factor-β1 (TGF-ß1) gene polymorphisms with the susceptibility to liver cirrhosis (LC), controversial results exist. Consequently, we performed a meta-analysis to accurately evaluate the relationship of TGF-ß1-509C/T and codon 10T/C polymorphisms with the risk of LC introduced by chronic hepatitis B/V virus (HBV/HCV) infection. A total of 9 case-control studies, involving 985 LC patients and 909 controls, were recruited for meta-analysis. The results suggested a significant association between the -509C/T polymorphism and LC risk in the total population. Stratification by ethnicity revealed similar associations in Egyptian and Caucasian populations, but not in Asian populations. Subgroup analyses by different etiologies also showed similar associations in HCV-induced LC, but not in HBV-induced LC. However, the overall data failed to show a significant association between codon 10T/C polymorphism and the risk of LC in the study. We concluded that TGF-ß1-509C/T polymorphism was significantly associated with LC susceptibility, while the codon 10T/C polymorphism seemed to have a limited role in predicting the occurrence of LC induced by HBV/HCV infection.

Development of gene polymorphisms in meditators of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide, the morbidity of which closely correlates with diversity of ethnicity, minority, family and location. Its histology spans from simple steatosis, to nonalcoholic steatohepatitis, which ultimately results in fibrosis, cirrhosis and hepatocellular carcinoma. The accelerating prevalence of NAFLD is due to an incremental incidence of metabolic syndrome that is distinguished by dyslipidemia, glucose impairment, obesity, excessive oxidative stress and adipocytokine impairment. Additionally, the pathogenesis of NAFLD is thought to be a multifactorial and complicated disease associated with lifestyle habits, nutritional factors and genetics. However, the pathogenesis and underlying mechanism in the development of NAFLD caused by genetics remains unclear. People have been increasingly emphasizing on the relationship between NAFLD and gene polymorphisms in recent years, with the aim of having a comprehensive elucidation of associated gene polymorphisms influencing the pathogenesis of the disease. In the current article, the authors attempted to critically summarize the most recently identified gene polymorphisms from the facets of glucose metabolism, fatty acid metabolism, oxidative stress and related cytokines in NAFLD that contribute to promoting the progression of the disease.

The Synergistic Effect of TNFα -308 G/A and TGFβ1 -509 C/T Polymorphisms on Hepatic Fibrosis Progression in Hepatitis C Virus Genotype 4 Patients

Tumor necrosis factor-alpha (TNFα) and transforming growth factor-beta (TGFβ1) cytokines are highly implicated in liver fibrosis. Polymorphisms in these cytokines affect their expression, secretion, and activity. This study aimed to evaluate the influence of TNFα -308 G/A and TGFβ1 -509 C/T polymorphism on hepatic fibrosis progression in Egyptian patients with hepatitis C virus (HCV) genotype 4. Genotyping of TNFα -308 G/A and TGFβ1 -509 C/T was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in 122 subjects (50 healthy controls and 72 HCV patients). Also, serum TNFα and TGFβ1 levels were detected by enzyme-linked immunosorbent assay (ELISA). The genotyping results of early (F0-F1, n = 36) and late (F2-F4, n = 36) HCV fibrosis patients showed that late fibrosis patients had higher TNFα -308 AA genotype and TGFβ1 -509 TT genotype than early fibrosis patients (p = 0.016, 0.028, respectively). Moreover, the TNFα and TGFβ1 serum levels were significantly higher in HCV patients with TNFα A containing genotypes (GA+AA) (p = 0.004) and patients with TGFβ1 T containing genotypes (CT+TT) (p = 0.001), respectively. The combined unfavorable TNFα (GA/AA) and TGFβ1 (CT/TT) genotypes were highly associated with abnormal liver function parameters and were significantly higher in high activity (A2-A3) and late fibrosis (F2-F4) HCV patients (p = 0.023, 0.029). The multivariate analysis results confirmed that the combined TNFα-308 (AA) and TGFβ1 -509 (TT) unfavorable genotypes increased the risk of hepatic fibrosis progression by 6.4-fold than combined favorable genotypes (odds ratio: 6.417, 95% confidence interval [1.490-27.641], p = 0.013). In conclusion, both TNFα -308 G/A and TGFβ1 -509 C/T polymorphisms synergistically influence the hepatic fibrosis progression and can be used as potential biomarkers to predict hepatic disease progression in chronic hepatitis C patients.

No association between TGF-β1 polymorphisms and risk of nasopharyngeal carcinoma in a large North African case-control study

Background

Genetic susceptibility plays a key role in the development of nasopharyngeal carcinoma (NPC) and in fact the disease presents with an unusually high incidence in certain regions of the world like North Africa. We investigated the association between polymorphism of the Transforming growth factor-β1 (TGF-β1) and risk of NPC in North Africa. TGF-β1 is a multifunctional cytokine that acts as both a tumor suppressor and a stimulator of cancer development; it has been shown to influence risk of numerous other carcinomas including lung, breast and prostate cancer.

Methods

TGF-β1 polymorphisms C-509T and T869C were studied in a large North African sample of 384 NPC cases and 361 controls, matched for age, sex and urban or rural residence in childhood. Genotypes were determined using polymerase chain reaction–restriction fragment length polymorphism.

Results

No association was observed between individual single nucleotide polymorphisms or their haplotypes and NPC susceptibility (for TGF-β1 C-509T: OR = 0.74; 95 % CI 0.46 − 1.18; for TGF-β1 T869C: OR = 0.86; 95 % CI 0.56 − 1.31), even when the samples were stratified by age, gender and TNM stage.

Conclusion

Contrary to what has been observed in Asian samples, in our North African sample, the TGF-β1 C-509T and T869C polymorphisms did not substantially influence NPC susceptibility.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-016-0337-8) contains supplementary material, which is available to authorized users.

TGF-β1 gene - 509C > T promoter polymorphism modulates TGF-β1 levels in hepatitis E patients

Elevated levels of transforming growth factor-β1 (TGF-β1) and its positive correlation with Foxp3 expression in hepatitis E patients have indicated involvement of TGF-β1 in hepatitis E pathogenesis. The current study determined polymorphisms in TGF-β1 gene, plasma TGF-β1 levels and T effector (Teff) cell proliferation and explored their association in a case control study. Polymorphisms in three selected sites (- 509C > T, + 869T > C and + 915G > C) of TGF-β1 gene by PCR & restriction fragment length polymorphism methods, plasma TGF-β1 quantitation by ELISA and Teff (CD4 + CD25 -) cell proliferation by CFSE method were carried out in 277 hepatitis E patients (HE) with self-limiting infection and 233 ethnically matched healthy controls (HCs) from western India. Frequency of CT genotype of - 509C > T site was significantly higher in hepatitis E patients compared to healthy controls (p = 0.017; OR 1.53, 95% CI 1.07-2.17). Plasma TGF-β1 levels were significantly higher in HE compared to HCs. TGF-β1 level of patient group having CT genotype of - 509C > T site was significantly higher compared to those having CC or TT genotypes. Teff cell proliferation was negatively correlated with plasma TGF-β1 levels in HE patients (r = - 0.568; p = 0.014). Influence of TGF-β1 promoter (- 509C > T) polymorphism on plasma TGF-β1 levels and inverse correlation of Teff cell proliferation with plasma TGF-β1 levels in self-limiting hepatitis E patients suggest key role of TGF-β1 in augmentation of reported T regulatory cell mediated pathogenesis in hepatitis E.

Th1/Th2 cytokines and their genotypes as predictors of hepatitis B virus related hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the predominant type of primary liver cancer, is one of the most serious life-threatening malignancies, worldwide. In majority of the cases, HCC develops after prolonged and persistent chronic liver disease. hepatitis B virus (HBV) or HCV infection is prominent etiological factors, attributing to this condition. It has been well documented that HBV, being the inducer of chronic inflammation, is the main causative agent in causing HCC, particularly in Asian countries. The HBV infection leads to a wide range of clinical symptoms from carrier state to malignancy. Cytokines being immune-modulatory molecules, are the key mediators in the defense mechanism against viral infection. In this regard, this review will detail the substantial role of key Th1: interleukin 1 (IL-1), IL-2, IL-12, tumor necrosis factor-α, interferon-γ; Th2: IL-4, IL-10 and non Th1/Th2: IL-6, transforming growth factor-β1 cytokines genotypes in analyzing the variability in the clinical manifestations in an HBV-afflicted individual, which might finally, culminates into HCC. Since cytokine production is regulated genetically, the cytokine promoter region single-nucleotide polymorphisms induced changes, greatly affects the cytokine production, thus resulting into differential outcome of immune balance.

Role of transforming growth factor-β1 in serum and - 509 C>T promoter gene polymorphism in development of liver cirrhosis in Egyptian patients

Objectives

Liver cirrhosis is a condition in which the liver slowly deteriorates and malfunctions due to chronic injury. HCV is one of the major causes of liver fibrosis and ultimate progression to cirrhosis. Transforming growth factor-beta1 (TGF-β1), one of the three isoforms of TGF-β, is a pleiotrophic cytokine that regulates the proliferation and differentiation of cells, embryonic development, wound healing and angiogenesis. This study aimed to evaluate the role of serum TGF-β1 and − 509 C>T promoter gene polymorphism in the development of liver cirrhosis.

Design and methods

Besides routine liver profiles, serum TGF-β1 was measured in 40 liver cirrhosis patients and 40 controls using ELISA technique. TGF-β1 − 509 C>T promoter gene polymorphism was detected using PCR-RFLP technique.

Results

TGF-β1 − 509 CT and TT genotype frequencies were significantly higher in the cirrhotic group (52.5%, 25%; respectively) than control group (10%, 7.5%; respectively); OR = 16.238 (95% CI 5.391–48.914, p < 0.05). The − 509 T allele carriers are more prone to develop liver cirrhosis than − 509 C allele carriers; OR = 7.359 (95% CI 3.325–16.288, p < 0.05). Serum TGF-β1 was significantly higher in cirrhotic group (11.79 ± 1.45 ng/ml) than control group (8.67 ± 1.23 ng/ml); p < 0.05. Also serum TGF-β1 was significantly higher in TT genotype than CT and CC genotypes (p < 0.05). A significant positive correlation was observed between serum TGF-β1 and alkaline phosphatase (r = 0.559, p < 0.05); AST (r = 0.573, p < 0.05). A significant negative correlation was observed between serum TGF-β1 and albumin (r = − 0.331, p < 0.05).

Conclusion

There is an association between serum TGF-β1, − 509 CT and TT genotypes of TGF-β1 gene and the higher risk for liver cirrhosis development of liver cirrhosis.

Establishment of a rat model of alcoholic liver fibrosis and detection of hepatic expression of Smad7/TGF-β

AIM: To develop a suitable rat model of alcoholic liver fibrosis, which is easily available and low in cost with a high success rate, and to detect the alteration of expression of genes involved in the pathogenesis of alcoholic liver disease.

METHODS: Rats were raised individually in respective cages and were fed ad libitum. Rats were divided into two groups: a normal control group and an experimental group. The normal control group was given a normal diet with alcohol-free water. The experimental group was further divided into three subgroups, namely, a normal diet subgroup, a high fat diet subgroup and a limited high fat diet subgroup. Commercially available Chinese spirit was diluted into different concentrations (6%, 9%, 12%, 20%) using distilled water and used as the source of alcohol consumption for rats in the experimental group. Rats in the experimental group were fed distilled water containing 6% (v/v) alcohol at the beginning of the experiment, and the concentration of alcohol was gradually increased to 20% within 4 wk. Ultimately, water containing 20% alcohol was maintained towards the end of the study. At the end of the experiment, livers of rats were dissected for histological studies whereas serum samples were taken to detect the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The mRNA and protein expression of transforming growth factor β1 (TGF-β1) and Smad7 in liver tissues was detected by real-time PCR and Western blot, respectively.

RESULTS: No pathological changes were observed in the liver of rats in the normal control group. However, rats in the experimental group demonstrated histopathological changes such as fatty change, inflammation as well as fibrosis. The histopathological changes were most severe in the subgroup fed a limited high fat diet, followed by those fed a high fat diet. Fatty changes were observed in the liver of rats in the experimental subgroup fed a normal diet. A small amount of collagen fibrils, inflammation and a more severe fatty change were found in the liver of rats fed a high fat diet. Bundles of closely packed collagen fibrils, inflammation, and fatty change were observed in rats fed a limited high fat diet. Serum levels of AST and ALT were higher in the experimental group compared to the normal control group. The subgroup fed a normal diet had lower levels of AST and ALT compared to the other two subgroups, although no significant difference was seen between subgroups fed a high fat diet and a limited high fat diet. Protein expression of TGF-β1 and Smad7 was positively correlated with their mRNA levels, respectively. TGF-β1 expression level in the normal control group was lower compared to the three experimental subgroups, and the level was positively correlated with the severity of hepatic pathological changes. Smad7 expression was shown to be higher in the normal control group compared to the experimental subgroups. However, there was no correlation between the level of Smad7 and hepatic pathological changes.

CONCLUSION: Feeding a limited high fat diet with alcohol ad libitum in rats is a convenient, low cost method for developing an animal model of alcoholic liver disease with a high rate of success. Inability of Smad7 to inhibit the TGF-β1 pathway contributes to the development of alcoholic liver fibrosis.

Lack of Association Between Transforming Growth Factor Beta 1 -509C/T and +915G/C Polymorphisms and Chronic Hepatitis B in Iranian Patients

BACKGROUND

Chronic hepatitis B is one of the world's major health concerns [corrected]. The etiological agent of this infection is hepatitis B virus (HBV), which can evade the immune system response. Transforming growth factor beta 1 (TGF-β1) can act against HBV by suppressing the viral replication. The TGF-β1 also plays an important role in preventing liver damage in chronically HBV infected patients.

OBJECTIVES

In this study, the association of TGF-β1 +915G/C and -509C/T gene polymorphisms with chronic hepatitis B was evaluated in Iranian patients.

MATERIALS AND METHODS

A population-based case-control study was conducted in Taleghani Hospital, Tehran. A number of 220 patients with chronic hepatitis B and the same number of healthy control subjects were designated the case and the control groups. The PCR-Restriction Fragment Length Polymorphism Method (PCR-RFLP) method was used for genotyping both polymorphisms. Ten percent of the control samples were sequenced to confirm the results.

RESULTS

No statically significant differences in genotype distribution and allele frequency were observed for both polymorphisms between healthy controls and patients with chronic hepatitis B.

CONCLUSIONS

There was no association between TGF-β1 -509C/T and +915G/C polymorphisms with chronic hepatitis B and it seems that these changes do not play a significant role in increasing the risk of chronic infection in Iranian patients [corrected].

Association between TGFB1 915G/C polymorphism and susceptibility to chronic hepatitis C virus infection: A meta-analysis

The human transforming growth factor-β1 (TGF-β1) gene, namely TGFB1, contains several single-nucleotide polymorphisms (SNPs) and some of the polymorphic variants were shown to affect the TGF-β1 protein levels. A number of studies reported the association between 915G/C polymorphism and susceptibility to chronic hepatitis C virus (HCV) infection. However, the results were inconsistent. This meta-analysis was conducted to assess the association of TGFB1 915G/C polymorphism with susceptibility to chronic HCV infection. PubMed, ISI Web of Knowledge, ScienceDirect and Google Scholar databases were systematically searched up to August, 2013 to identify relevant studies. The pooled odds ratios (ORs) with their corresponding 95% confidence intervals (95% CIs) were calculated in 5 genetic comparison models (C vs. G, CC vs. GG, GC vs. GG, CC vs. GG+GC and CC+GC vs. GG). The Galbraith plot and subgroup analyses based on ethnicity, genotyping methods, sample size and fibrosis were performed to investigate possible sources of heterogeneity. A sensitivity analysis and assessment of publication bias were also conducted. Finally, 8 eligible case-control studies on TGFB1 915G/C polymorphism, including a total of 910 cases and 632 controls, were included in this meta-analysis. Overall, there was no evidence of any gene-disease association obtained from the subgroup analyses. Therefore, this meta-analysis demonstrated that there is no association between TGFB1 915G/C polymorphisms and susceptibility to chronic HCV infection.

Effect of IL-12B, IL-2, TGF-β1, and IL-4 polymorphism and expression on hepatitis B progression

The hepatitis B virus (HBV) infection-induced chronic inflammation is considered to be the major etiological factor for HBV-related disease chronicity. Cytokines act as the key coordinators of the inflammatory responses involved in HBV disease pathogenesis. The present study assessed association among IL-12B(+1188), IL-2(-330), TGF-β1(-509), and IL-4(-590) genotypes; mRNA; and protein levels with HBV-hepatocellular carcinoma (HCC) risk in India. For this, 403 subjects (153 controls, 67 inactive HBV-carriers, 62 chronic-active HBV patients, 62 HBV-cirrhotics, and 59 HBV-HCC ssubjects) were enrolled in the study. The genotyping was carried by polymerase chain reaction (PCR)-restriction fragment length polymorphism (IL-12+1188A/C, IL-2-330T/G, and TGF-β1-509C/T), and allele specific (AS)-polymerase chain reaction (IL-4-590C/T). Enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction methods were used for assessing protein and the mRNA expression, respectively, of the mentioned cytokines. The study revealed that the IL-12B(+1188) CC genotype shared a significant positive association with hepatitis, among controls. While, in the case of IL-2(-330), both the TG and GG genotypes were not significantly associated with HCC risk. The TGF-β1(-509) TT genotype acted as a potential protective factor for cirrhosis and the HCC risk, among carriers. On the contrary, the IL-4(-590) CT genotype was found to be a vital protective factor for the development of hepatitis, among carriers. Besides, IL-12B, TGF-β1, and IL-2 seem to be majorly involved in the development of HCC, while, IL-4 might be responsible for the progression of the HBV disease till cirrhosis development. These initial findings are indicative of the vital role of genotypes and/or levels of IL-12B, IL-2, IL-4, and TGF-β1 in HBV disease chronicity in Indian population.

Association between TGF-β1 polymorphisms and hepatocellular carcinoma risk: a meta-analysis

BACKGROUND

Associations between transforming growth factor (TGF)-β1 polymorphisms and hepatocellular carcinoma (HCC) risk remained controversial. Therefore, we performed this meta-analysis to investigate these associations.

METHODS

We searched Pubmed, EMBASE, Chinese National Knowledge Infrastructure (CNKI), and Wanfang databases for studies before March 2013. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to calculate the strength of association.

RESULTS

A total of 14 studies were included in this meta-analysis. TGF-β1 +869C/T polymorphism was significantly associated with HCC risk (OR=1.74, 95% CI: 1.22-2.47, p=0.002). In addition, a significant association between -509C/T polymorphism and HCC risk was observed (OR=1.40, 95% CI: 1.15-1.70, p=0.0007). Furthermore, significant associations between these polymorphisms and HCC risk were found in Asians and population-based studies.

CONCLUSIONS

Our meta-analysis suggested that the TGF-β1 +869C/T and -509C/T polymorphisms may be risk factors for developing HCC.

Important roles played by TGF-β in hepatitis B infection

Hepatitis B virus (HBV) which includes, fulminant, acute, chronic, asymptomatic, and occult HBV infection is the most prevalent virus that leads to human liver diseases. Chronic, asymptomatic, and occult infection can induce further sever diseases such as hepatocellular carcinoma (HCC) and cirrhosis of the liver. The underlying mechanisms that allow progression of the prolonged forms of the infection and subsequent HCC or cirrhosis of the liver are yet to be clarified. However, many researchers have suggested that immunological and genetic parameters may play important roles in the etiology of hepatitis B. Transforming growth factor beta (TGF-β) is an important cytokine with dual regulatory functions in the immune system and in the responses against viral infections. However, the pathways and mechanisms controlling these are not fully understood. The crucial roles of TGF-β in the development of Th17 and T regulatory lymphocytes, the main cell types involved in autoimmunity and destructive immune related diseases, have been documented and this provides insights into TGF-β function during hepatitis infection and subsequent HCC and cirrhosis of the liver. Recent findings also confirm that TGF-β directly alters hepatocyte function during hepatitis B, hence, the aim of this review is to address the current data regarding the association and status of TGF-β with hepatitis B infection and its related disorders including HCC and cirrhosis of the liver.

Transforming growth factor beta-1 C-509T polymorphism and cancer risk: a meta-analysis of 55 case-control studies

AIM

To investigate the association of transforming growth factor-beta 1 (TGF-β1) C-509T polymorphism and susceptibility to cancer by means of meta-analysis.

METHODS

An extensive search was performed to identify eligible case-control studies investigating such a link. The strength of the association between TGF-β1 C-509T polymorphism and cancer risk was assessed by pooled odds ratios (ORs) and 95%confidence intervals (95%CIs) in fixed or random effects models.

RESULTS

55 published case-control studies with a total number of 21,639 cases and 28,460 controls were included. Overall, there was no association between TGF-β1 C-509T and cancer risk in all genetic comparison models (TT vs. CC: OR=1.01, 95%CI=0.89-1.15; T vs. C: OR=1.01, 95%CI=0.94-1.07). However, a stratified analysis by cancer type indicated -509 T allele was significantly associated with decreased risk of colorectal cancer (CRC) (TT vs. CT/CC: OR=0.85, 95%CI=0.76-0.95), especially for Caucasians (TT vs. CT/CC: OR=0.83, 95%CI=0.71-0.98) and for population-based studies (TT vs. CT/CC: OR=0.78, 95%CI=0.68- 0.89).

CONCLUSION

This meta-analysis suggested that TGF-β1 C-509T polymorphism might contribute to a decreased risk on colorectal cancer susceptibility, especially for Caucasians.

TGF-β1 -509C/T (or +869T/C) polymorphism might be not associated with hepatocellular carcinoma risk

Many studies have reported the role of transforming growth factor-β1 (TGF-β1) -509C/T or +869T/C polymorphism with hepatocellular carcinoma (HCC) risk. However, these studies have yielded conflicting results. Hence, we performed this meta-analysis to investigate the association between TGF-β1 -509C/T or +869T/C polymorphism and HCC. A total of 11 studies including 2,577 HCC cases and 4,107 controls were included in the meta-analysis. Overall, TGF-β1 -509C/T (or +869T/C) polymorphism was not associated with HCC risk (homogeneous co-dominant model: OR = 1.29, 95 % CI = 0.88-1.89; heterogeneous co-dominant model: OR = 1.15, 95 % CI = 0.91-1.45; dominant model: OR = 1.14, 95 % CI = 0.87-1.48; recessive model: OR = 1.15, 95 % CI = 0.89-1.49). In the subgroup analysis, TGF-β1 -509C/T (or +869T/C) polymorphism was significantly associated with HCC risk in Caucasians under the recessive model (OR = 1.65, 95 % CI = 1.07-2.55) but not in other genetic models. In addition, we did not observe significant association in Asians under all genetic models. In conclusion, our meta-analysis indicates that TGF-β1 -509C/T (or +869T/C) polymorphism was not associated with risk of HCC, although a marginal association was found for Caucasians. However, a study with the larger sample size is needed to further evaluate gene-environment interaction on the association.

Transforming growth factor-β genetic polymorphisms on development of liver cirrhosis in a meta-analysis

Transforming growth factor-β (TGF-β) protein has been supposed to be a risk factor for liver cirrhosis; however, the associations between its genes (TGF-β -509C>T and +869T>C) and liver cirrhosis remained unclear. This study was to quantitatively analyze the correlations by using a meta-analysis. Pubmed, Embase, Wanfang databases were retrieved up to November 1st, 2011. Odds ratio (OR) and 95 % confidence interval (95 %CI) were used to demonstrate the strength of association, and P < 0.05 of Z test indicated statistical significance. Combined analyses were performed by using fixed or random-effect model, depending on between-study heterogeneity. Seven studies were for TGF-β -509C>T polymorphism, and eight studies were for +869T>C polymorphism. Combined results indicated that neither TGF-β -509C>T nor +869T>C polymorphisms were associated with risk of liver cirrhosis [OR (95 % CI): 0.79 (0.60-1.04) for CT vs. TT of -509C>T and 0.87 (0.68-1.12) for CT vs. CC of +869T>C], with no between-study heterogeneity. In addition, subgroups analyses still inferred that two polymorphisms were not associated with risk of liver cirrhosis for HBV-infected patients, Asians and for Population-based studies. This meta-analysis indicated that neither TGF-β -509C>T nor +869T>C polymorphisms were associated with risk of liver cirrhosis, regardless of HBV infection or not.

Correlation between TGF-β1-509 C>T polymorphism and risk of digestive tract cancer in a meta-analysis for 21,196 participants

The association between transforming growth factor β1 (TGF-β1)-509 C>T and risk of digestive tract cancer (DTC) remained uncertain as previous studies reported conflicting results. The aim of this study was to assess the association by using a meta-analysis. The databases of MEDLINE, EMBASE and WANGFANG (Chinese database) were retrieved, and latest update was on 2nd February, 2012. Pooled odds ratio and 95% confidence interval (OR and 95% CI) were calculated by using a fixed- or random-effect model. Ultimately, twenty nine case-control studies with 8664 cases and 12,532 controls were included in this meta-analysis. Overall, there was no association between TGF-β1-509 C>T and risk of DTC in all genetic comparison models (OR and 95% CI: 0.96 and 0.81-1.15 for TT vs. CC, 0.98 and 0.91-1.05 for T carriers vs. C carriers). When subgroup analyses were conducted according to ethnicity, types of cancer and sample size, T allele was significantly associated with decreased risk of DTC for Caucasians and for large sample-sized studies, and was associated with decreased risk of colorectal cancer (OR and 95% CI for TT vs. CC: 0.82 and 0.70-0.97 for Caucasians, 0.80 and 0.68-0.98 for large sample-sized studies, 0.78 and 0.62-0.97 for colorectal cancer). This study indicated that TGF-β1-509 C>T polymorphism was probably associated with risk of DTC, especially for Caucasians. Because of modest limitation, our findings should be confirmed by future studies.

Influence of transforming growth factor-β1 and tumor necrosis factor-α genes polymorphisms on the development of cirrhosis and hepatocellular carcinoma in chronic hepatitis C patients

BACKGROUND

Host genetic factors may affect clinical outcomes of hepatitis C virus (HCV) infection; however, the possible mechanisms remain largely unknown. This study aimed to evaluate transforming growth factor-β1 (TGF-β1)-509 and tumor necrosis factor-α (TNF-α)-308 genes polymorphisms as a risk factors for cirrhosis and hepatocellular carcinoma (HCC) in chronic hepatitis C patients.

MATERIALS AND METHODS

Two hundred and eighty HCV patients (152 patients with cirrhosis, 128 patients with HCC) and 160 controls were enrolled in the study. Polymorphisms of TGF-β1-509 and TNF-α-308 gene were determined using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Serum TGF-β1 and TNF-α were determined using ELISA.

RESULTS

TGF-β1-509 TT, TNF-α-308 AA and GA genotypes frequencies were significantly increased in cirrhotic and HCC groups. Serum TGF-β1 and TNF-α level were significantly increased in TGF-β1-509 TT and TNF-α-308 AA genotypes respectively.

CONCLUSION

TGF-β1-509 and TNF-α-308 genes polymorphisms are associated with risk of liver cirrhosis and HCC in patients with chronic HCV infection.

Association between transforming growth factor-β1 polymorphisms and hepatocellular cancer risk: A meta-analysis

AIM

  The association between transforming growth factor-β1 (TGF-β1) gene polymorphisms and hepatocellular cancer (HCC) risk has been widely reported, but results were somewhat controversial. To derive a more precise estimation of the relationship between TGF-β1 polymorphisms and HCC risk, we conducted a meta-analysis of all available studies relating the C-509T and/or T869C polymorphisms of the TGF-β1 gene to the risk of developing HCC.

METHODS

  Two investigators independently searched the MEDLINE, PubMed, Web of Science, Embase, CNKI (China National Knowledge Infrastructure) and CBM (Chinese Biomedical Literature database) for the period up to August 2011.

RESULT

  A total of nine case-control articles were identified. Five studies with 1825 cases and 2869 controls for C-509T polymorphism, and six studies with 536 cases and 1496 controls for T869C polymorphism were included. In the overall analysis, no significant association between the polymorphisms and risk of HCC was observed. Stratified analysis showed that significant association between C-509T polymorphism and HCC was present only in controls with liver disease (T vs. C: odds ratio [OR] = 0.769, 95% confidence interval [CI] = 0.661-0.895; TT vs. CC: OR = 0.570, 95% CI = 0.412-0.788; TT/TC vs. CC: OR = 0.668, 95% CI = 0.523-0.854; TT vs.

TC/CC

OR = 0.717, 95% CI = 0.550-0.934), but not in healthy controls. With respect to T869C polymorphism, only a decreased risk was found in recessive models in controls with liver disease.

CONCLUSIONS

  This meta-analysis supports that the TGF-β1 C-509T polymorphism may act in a protecting role in HCC susceptibility in populations with related liver disease.

Genome-wide association studies and genetic risk assessment of liver diseases

Genetic tests can help clinicians to diagnose rare monogenic liver diseases. For most common liver diseases, however, multiple gene variants that have small to moderate individual phenotypic effects contribute to the overall risk of disease. An individual's level of risk depends on interactions between environmental factors and a wide range of modifier genes, which are yet to be identified systematically. The latest genome-wide association studies in large cohorts of patients with gallstones, fatty liver disease, viral hepatitis, chronic cholestatic liver diseases or drug-induced liver injury have provided new insights into the pathophysiology of these illnesses and have suggested the contribution of previously unsuspected pathogenic pathways. Studies in mouse models have identified further susceptibility genes for several complex liver diseases. As a result, in the future polygenic risk scores might help to define subgroups of patients at risk of developing liver diseases who would benefit from preventative measures and/or personalized therapy. Now that whole-genome sequencing is possible, comprehensive strategies for integrating genomic data and counseling of patients need to be developed.

The genotypes of IL-1 beta and MMP-3 are associated with the prognosis of HCV-related hepatocellular carcinoma

BACKGROUND AND AIM

Cytokines and matrix metalloproteinases (MMPs) are involved in tumor growth, invasion, and remote metastasis in various cancers. Recently, functional gene polymorphisms in these cytokines and MMPs have been found, and some reports have revealed an association between these polymorphisms and the prognosis of various cancers. In this study, we examined the relationship between the gene polymorphisms of interleukin 1 beta (IL-1b), IL-1 receptor antagonist (IL-1 RN), transforming growth factor beta 1 (TGF-b1), MMP-1, MMP-3, and MMP-9 and the prognosis of hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC).

METHODS

We enrolled 92 HCV-related HCC patients in the study, and gene polymorphisms of IL-1b -31 C/T, IL-1 RN variable number of tandem repeats (VNTR), TGF-b1 +869 C/T, MMP-1 -1,607 1G/2G, MMP-3 -1,171 5A/6A, and MMP-9 -1,562 C/T were analyzed.

RESULTS

In HCC clinical features, TGF-b1 C carriers and MMP-3 5A carriers had significantly larger HCC diameters than TGF-b1 T and MMP-3 6A homozygotes. In HCC prognosis, IL-1b T homozygotes and MMP-3 5A carriers had a significantly poorer prognosis than IL-1b C carriers and MMP-3 6A homozygotes. Those with a combination of IL-1b T homozygosity and MMP-3 5A had synergistically poorer HCC prognosis.

CONCLUSION

The IL-1b -31 T allele and MMP-3 5A allele are cooperative risk factors for poor prognosis in HCC patients, suggesting that these gene polymorphisms might be potential markers for predicting the prognosis of HCC patients.

TGFbeta1 T29C polymorphism and cancer risk: a meta-analysis based on 40 case-control studies

Transforming growth factor-beta1 (TGFbeta1) plays a significant role in regulating cellular proliferation and apoptosis. The TGFbeta1 T29C polymorphism reportedly affects cancer risk, but pertinent studies offer conflicting results. We therefore performed a meta-analysis based on 40 studies from 32 publications, assessing the strength of the association using odds ratios with 95% confidence intervals. Overall, no evidence has indicated that individuals carrying CC or CT genotypes had significantly increased cancer risks, compared with TT genotype carriers [CC vs. TT: odds ratio (OR)=1.10, 95% confidence interval (95% CI)=1.00-1.21, P=0.06; CT vs. TT: OR=1.07, 95% CI=0.99-1.16, P=0.09). However, stratified analysis by cancer type and ethnicity indicated a significantly increased risk of prostate cancer (CT vs. TT: OR=1.28, 95% CI=1.01-1.61, P=0.04) and cancer in those of Asian descent (CC vs. TT: OR=1.26, 95% CI=1.03-1.53, P=0.02; CT vs. TT: OR=1.20, 95% CI=1.01-1.43, P=0.04). This association was also observed in the dominant model for prostate cancer. Although not all bias could be eliminated, this meta-analysis suggested that TGFbeta1 29C was a low-penetrant risk factor for prostate cancer and cancer in Asians. A larger single study is still required to evaluate any association with other types of cancer or in other populations.