Relationship between gene polymorphisms of two cytokine genes (TNF-α and IL-6) and occurring of lung cancers in the ethnic group Han of China

Interleukin polymorphisms and protein levels associated with lung cancer susceptibility and phenotypes

BACKGROUND

We conducted a comprehensive analysis to explore whether multiple interleukin (IL), IL-1β, IL-4, IL-6, IL-8 and IL-10, polymorphisms and IL proteins (IL-6, IL-10) relate to lung cancer (LC) susceptibility or clinical characteristics.

METHODS

We performed the standard meta-analysis procedures according to PRISMA. The odds ratio (OR) and mean difference (MD) were used for analysis.

RESULTS

We investigated 11 variants from 43 articles, and found that IL-1β rs16944 (p = 0.04) and IL-10 rs1800872 (p = 0.003) decreased while IL-10 rs1800896 (p = 0.007) increased LC risks. We also found that IL-1β rs1143627 decreased NSCLC risks (p = 0.03). The heterozygotes and homozygotes contributed differently. In addition, another 15 articles were involved to explore the relationship between IL proteins and LC. We found that LC patients accounted for higher serum IL-6 of 16.60 pg/mL (p < 0.00001) and higher serum IL-10 of 3.47 pg/mL (p = 0.02) than that of controls. Furthermore, IIIA-Ⅳ LC patients tended to have higher proportion of positive IL-6 staining in lung tumor tissue in contrast with IA-IIB patients by TNM stage (p = 0.0002).

CONCLUSIONS

Four variants from IL-1β and IL-10, and serum IL-6 and IL-10 levels are associated with LC risks.

Statistical meta-analysis to investigate the association between the Interleukin-6 (IL-6) gene polymorphisms and cancer risk

A good number of genome-wide association studies (GWAS), including meta-analyses, reported that single nucleotide polymorphisms (SNPs) of the IL-6 gene are significantly associated with various types of cancer risks, though some other studies reported insignificant association with cancers, in the literature. These contradictory results may be due to variations in sample sizes and/or deficiency of statistical modeling. Therefore, an attempt is made to provide a more comprehensive understanding of the association between the IL-6 gene SNPs (rs1800795, rs1800796, rs1800797) and different cancer risks, giving the weight on a large sample size, including different cancer types and appropriate statistical modeling with the meta-dataset. In order to attain a more reliable consensus decision about the association between the IL-6 gene polymorphisms and different cancer risks, in this study, we performed a multi-case statistical meta-analysis based on the collected information of 118 GWAS studies comprising of 50053 cases and 65204 control samples. Results from this Meta-analysis indicated a significant association (p-value < 0.05) of the IL-6 gene rs1800796 polymorphism with an overall increased cancer risk. The subgroup analysis data based on cancer types exhibited significant association (p-value < 0.05) of the rs1800795 polymorphism with an overall increased risk of cervical, liver and prostate cancers; the rs1800796 polymorphism with lung, prostate and stomach cancers; and the rs1800797 polymorphism with cervical cancer. The subgroup analysis of ethnicity data showed a significant association (p-value < 0.05) of an overall cancer risk with the rs1800795 polymorphism for the African and Asian populations, the rs1800796 polymorphism for the Asian only and the rs1800797 polymorphism in the African population. Comparative discussion showed that our multi-case meta-analyses received more support than any previously reported individual meta-analysis about the association between the IL-6 gene polymorphisms and cancer risks. Results from this study, more confidently showed that the IL-6 gene SNPs (rs1800795, rs1800796 and rs1800797) in humans are associated with increased cancer risks. Therefore, these three polymorphisms of the IL-6 gene have the potential to be evaluated as a population based rapid, low-cost PCR prognostic biomarkers for different types of cancers diagnosis and research.

Interaction of tobacco chewing and smoking habit with interleukin 6 promoter polymorphism in oral precancerous lesions and oral cancer

OBJECTIVE

Our study aims to determine the influence of smoking or tobacco chewing and the association of Interleukin 6 (IL-6) polymorphism, where G is substituted by A at the position - 596 (IL-6 - 596 G/A) and substitution of G by cytosine (C) at position - 572 (IL-6 - 572 G/C) on the susceptibility of precancerous oral lesions and oral cancer.

MATERIALS AND METHODS

The participants consisted of 250 subjects among which 75 were suffering from oral cancer, 75 subjects with precancerous oral lesions and 100 were healthy controls. Single-nucleotide polymorphism study (SNP) was done by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP).

RESULTS

IL-6 - 596 G/A SNP revealed genotypes, GG, and GA in subjects with precancerous oral lesions and oral cancer, and AA genotype was not found in any subject. IL-6 - 596 G/A was strongly associated with oral precancerous lesions but not with oral cancer. The present study reports that smokers carrying GA for IL-6 - 596 G/A were at several folds higher risk of developing oral precancerous lesions. Smokers with GC and CC for IL-6 - 572 G/C were at higher risk of developing oral precancerous lesions. No significant interaction was observed between these habits and IL-6 - 596 G/A and IL-6 - 572 G/C SNP with oral cancer.

CONCLUSION

The interaction of variant A allele of IL-6 - 596 G/A and C allele of IL-6 - 572 G/C polymorphism with smoking and increases the risk of oral precancerous lesions. Tobacco chewing was not related with IL-6 - 596 G/A or IL-6 - 572 G/C in oral precancerous lesions or oral cancer.

CLINICAL RELEVANCE

The study will help to determine the susceptibility of individuals with smoking or chewing habits to the development of oral precancerous lesion and oral cancer by monitoring the IL-6 SNPs which can be used as a biomarker for risk determination.

Associations of interleukin-6 gene polymorphisms with cancer risk: Evidence based on 49,408 cancer cases and 61,790 controls

Many molecular epidemiologic studies have shown that interleukin-6 (IL-6) polymorphisms are significantly associated with susceptibility for various cancers. However, the conclusions of these studies are inconsistent. The purpose of the present study was to explore the association between three common IL-6 loci (rs1800795, rs1800796, and rs1800797) and the risk for various cancers. We systematically searched the PubMed, Web of Science, Wanfang and China national knowledge infrastructure (CNKI) databases for relevant publications and obtained 108 eligible studies, involving 49,408 cancer patients and 61,790 cancer-free controls. Odds ratio (OR), 95% confidence interval (CI), and false positive reporting probability (FPRP) were used to evaluate cancer risk. All statistical analyses were performed using the R software meta package. We observed a non-significant association between rs1800795 and overall cancer risk, while rs1800797 was found to have a false positive association with overall risk of cancer. Subgroup analyses of rs1800797 also suggested non-significant association and rs1800795 played a protective role in liver cancer. Rs1800796 was found to be associated with overall cancer risk, particularly in Asian patients and those with prostate cancer. These findings provide evidence that IL-6 polymorphisms may affect cancer risk.

Genetic polymorphisms of IL-6 promoter in cancer susceptibility and prognosis: a meta-analysis

IL-6 is critical for tumorigenesis. However, previous studies on the association of IL-6 promoter polymorphisms with predisposition to different cancer types are somewhat contradictory. Therefore, we performed this meta-analysis regarding the relationship between IL-6 promoter single nucleotide polymorphisms and cancer susceptibility and prognosis. Up to April 2017, 97 original publications were identified covering three IL-6 promoter SNPs. Our results showed statistically significant association between IL-6 promoter and cancer risk and prognosis. Subgroup analysis indicated that rs1800795 was significantly associated with increased risk of cervical cancer, colorectal cancer, breast cancer, prostate cancer, lung cancer, glioma, non-Hodgkin’s lymphoma and Hodgkin’s lymphoma but not gastric cancer and multiple myeloma. Furthermore, rs1800796 was significantly associated with increased risk of lung cancer, prostate cancer and colorectal cancer but not gastric cancer. Additionally, rs1800797 was significantly association with breast cancer, non-Hodgkin’s lymphoma, B-cell lymphoma and diffuse large B-cell lymphoma but not gastric cancer. Simultaneously, rs1800795 and rs1800796 were associated with a significantly higher risk of cancer in Asia and Caucasian, rs1800797 was associated with a significantly risk of cancer in Caucasian but not in Asia. Furthermore, IL-6 promoter polymorphisms were significantly associated with the prognosis of cancer. Considering these promising results, IL-6 promoter including rs1800795, rs1800796 and rs1800797 may be a tumor marker for cancer therapy.

Association of TNFα-308, IFNγ+874, and IL10-1082 gene polymorphisms and the risk of non-small cell lung cancer in the population of the South Indian state of Telangana

BACKGROUND

Cytokine-mediated inflammation is important in the pathogenesis of non-small cell lung cancer (NSCLC). Genetic polymorphisms in cytokine genes and their association with lung cancer in the Indian population have not been reported.

METHODS

For the first time, we analyzed genetic polymorphisms of TNFα ^-308, IFNγ ⁺⁸⁷⁴, and IL10 ^-1082 genes in 246 NSCLC patients and 250 healthy controls in the South Indian population from Telangana using ARMS PCR.

RESULTS

IFNγ⁺⁸⁷⁴ A/T and IL10^-1082 G/G gene polymorphisms were found to be significantly associated with NSCLC with 1.56- and 1.68-fold disease risk, respectively. There was no association between the risk of NSCLC and TNFα^-308 polymorphism. Gene polymorphisms stratified according to smoking revealed that IFNγ⁺⁸⁷⁴ A/T polymorphisms in smokers increased the disease risk by 2.91 fold. IL10^-1082 G/G polymorphisms showed 2-fold increased risk among patients who were smokers when compared to the controls. However, there was no association between TNFα^-308, IFNγ⁺⁸⁷⁴, and IL10^-1082 gene polymorphism and the stage of the NSCLC patients. The overall risk associated with the combination of these polymorphisms indicated that the TNFα^-308 G/A + IFNγ⁺⁸⁷⁴ A/T + IL10^-1082 G/G genotype increased the risk by 1.5 fold.

CONCLUSIONS

The results of our study indicate an association between cytokine gene polymorphisms and the risk of NSCLC in an Indian population.

Association of interleukin-6 genetic polymorphisms with risk of OSCC in Indian population

Purpose

Interleukin-6 (IL-6) encodes a cytokine protein, which causes inflammation, maintains immune homeostasis and plays an essential role in oral pathogenesis. The aim of this study was to evaluate the association between IL-6 (− 174 and − 572) G/C promoter gene polymorphisms and risk of OSCC among Indians.

Methods

Single nucleotide polymorphism in IL-6 genes was genotyped in OSCC patients and healthy controls by PCR-RFLP method. Genotype and allele frequencies were analyzed by chi-square test and strength of associations by odds ratio with 95% confidence intervals.

Results

Frequency distribution of IL-6 (− 174) G/C gene polymorphism was significantly associated with OSCC patients in comparison to healthy controls (OR: 0.541, CI: 0.356–0.822; p: 0.004. However, frequency of IL-6 (− 572) G/C gene polymorphism was not significantly associated with OSCC patients (p > 0.05).

Conclusion

The genotype GC and allele C of IL-6 (− 174) G/C gene polymorphism play a significant role in OSCC susceptibility.

•

We first demonstrate the IL-6 polymorphism in OSCC patients in Indian population.

•

We obtained the SNP of IL-6 (-174) is increase the risk of OSCC.

•

We also obtained the SNP of IL-6 (-572) and risk of OSCC

•

We evaluate the correlation of these IL-6 polymorphisms and progression of OSCC.

•

We identified the environmental factors and gene interactions with pathogenesis of OSCC.

Meta-analysis of the associations between TNF-α or IL-6 gene polymorphisms and susceptibility to lung cancer

BACKGROUND

Several studies have indicated an association between tumor necrosis factor-alpha (TNF-α) or interleukin (IL)-6 gene polymorphisms and lung cancer risk. However, the conclusions remain controversial.

METHODS

An English literature screening about case-control trials with regard to TNF-α (-308G/A) or IL-6 (174G/C) polymorphisms and lung cancer susceptibility was performed on PubMed, EMBASE, and EBSCO until November 2012. The pooled odds ratio (OR) and 95% confidence intervals (CI) were calculated using STATA 11.0. Sensitivity analysis was performed by sequential omission of individual studies. Publication bias was evaluated by Egger's linear regression test and funnel plots.

RESULTS

Eight eligible studies, including 1,690 patients and 1,974 controls, were identified in this meta-analysis. Compared with the control, no significant association was revealed between TNF-α-308G/A (GG + GC vs. CC: OR = 1.10, 95% CI: 0.73 to 1.64; GG vs. GC + CC: OR = 1.02, 95% CI: 0.81 to 1.27; GC vs. CC: OR = 1.13, 95% CI: 0.73 to 1.77; GG vs. CC: OR = 1.04, 95% CI: 0.80 to 1.36; G vs. C: OR = 1.03, 95% CI: 0.90 to 1.18) or IL-6 174G/C (GG + GC vs. CC: OR = 1.10, 95% CI: 0.73 to 1.64; GG vs. GC + CC: OR = 1.02, 95% CI: 0.81 to 1.27; GC vs. CC: OR = 1.13, 95% CI: 0.73 to 1.77; GG vs. CC: OR = 1.04, 95% CI: 0.80 to 1.36; G vs. C: OR = 1.03, 95% CI: 0.90 to 1.18) and lung cancer risk. The pooled OR remained unchanged after removing the maximum-weight study and no publication bias was observed.

CONCLUSIONS

The study raises the possibility of no correlation between the polymorphisms of the two genes and lung cancer susceptibility. However, further researches with large-sample or subgroup analyses are necessary to validate the conclusions.

Lack of association between a functional polymorphism (rs1800796) in the interleukin-6 gene promoter and lung cancer

Background

A number of studies have examined the association between interleukin-6 (IL-6) rs1800796 polymorphism and risk of lung cancer but revealed inconsistent results. The aim of this study was to clarify the association between IL-6 rs1800796 polymorphism and risk of lung cancer.

Methods

Literature databases including PubMed, Embase and CNKI were searched up to January 2014. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) under co-dominant model, dominant model and recessive model were estimated using random-effects model.

Results

A total of seven studies, including 2691 lung cancer cases and 3067 controls, were included in the meta-analysis. The results suggested that IL-6 rs1800796 polymorphism was not associated with risk of lung cancer under homogeneous co-dominant model (OR = 1.06, 95%CI = 0.73-1.54), heterogeneous co-dominant model (OR = 1.24, 95%CI = 0.96-1.60), dominant model (OR = 1.23, 95%CI = 0.95-1.58) and recessive model (OR = 0.96, 95%CI = 0.70-1.32). The association was still not significant in either never-smokers (OR = 1.19, 95%CI = 0.95-1.48) or ever-smokers (OR = 1.73, 95%CI = 0.89-3.36).

Conclusion

The present meta-analysis suggested that there was no association between IL-6 rs1800796 polymorphism and lung cancer, which was independent of smoking status.

Virtual Slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1060061508127855

Lack of association between -174G>C and -634C>G polymorphisms in interleukin-6 promoter region and lung cancer risk: a meta-analysis

Evidence suggested that the -174G>C and -634C>G polymorphisms in interleukin-6 (IL6) promoter region may modulate risk of lung cancer; however, the conclusion was still inconclusive. Therefore, we performed this meta-analysis to determine the association between IL6 -174G>C and -634C>G polymorphisms and lung cancer risk. The association strength was measured by odds ratios (ORs) and 95% confidence intervals (CI). Egger's test and Begg's test were performed to detect potential publication bias. By searching PubMed, EMBASE and China National Knowledge Infrastructure, we included 16 eligible studies in this meta-analysis, involving 6,202 lung cancer cases and 7,067 controls. Five studies about -174G>C polymorphism and 11 studies about -634C>G polymorphism were analyzed. By pooling eligible studies, we found no significant association of -174G>C with lung cancer risk (C vs. G: OR = 1.029; 95% CI, 0.957-1.106; heterogeneity, P = 0.478) and no statistic association of -634C > G with lung cancer susceptibility (G vs. C: OR = 1.050; 95% CI, 0.893-1.235; Heterogeneity, P < 0.001). No significant publication bias was observed. In conclusion, we found that -634C>G and -174G>C polymorphisms in IL6 promoter region were not associated with lung cancer risk.

Interleukin-6 -634C/G polymorphism is associated with lung cancer risk: a meta-analysis

Several studies have examined the associations of polymorphisms in interleukin-6 (IL6) with lung cancer (LC) risk. However, the results were conflicting. Thus, a meta-analysis was conducted to determine the relationship between IL6 polymorphisms and LC risk. Databases including PubMed, EMBASE, Wanfang, and China National Knowledge Infrastructure (CNKI) were searched. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. Thirteen studies were included in this meta-analysis. Overall, a significant association between IL6 -634C/G polymorphism and LC susceptibility was observed for GG + CG vs. CC (OR = 1.33, 95% CI 1.20-1.47, P < 0.00001). This polymorphism was also significantly associated with LC risk in Asians (OR = 1.33, 95% CI 1.20-1.47, P < 0.00001), female patients (OR = 1.30, 95% CI 1.11-1.52, P = 0.0009), male patients (OR = 1.25, 95% CI 1.03-1.52, P = 0.02), non-small cell lung cancer patients (OR = 1.21, 95% CI 1.03-1.41, P = 0.02), small cell lung cancer patients (OR = 1.91, 95% CI 1.23-2.97, P = 0.004), smokers (OR = 1.42, 95% CI 1.21-1.65, P < 0.0001), and non-smokers (OR = 1.32, 95% CI 1.13-1.53, P = 0.0003), respectively. No significant result was found for IL6 -174C/G polymorphism. This meta-analysis suggested that IL6 -634C/G polymorphism was a risk factor for LC.