Polymorphisms of the Interleukin 6 gene contribute to cervical cancer susceptibility in Eastern Chinese women

Comprehensive investigating of MMR gene in hepatocellular carcinoma with chronic hepatitis B virus infection in Han Chinese population

Hepatocellular carcinoma associated with chronic hepatitis B virus infection seriously affects human health. Present studies suggest that genetic susceptibility plays an important role in the mechanism of cancer development. Therefore, this study focused on single nucleotide polymorphisms (SNPs) of MMR genes associated with HBV-HCC. Five groups of participants were included in this study, which were healthy control group (HC), spontaneous clearance (SC), chronic hepatitis B group (CHB), HBV-related liver cirrhosis group (LC) and HBV-related hepatocellular carcinoma group (HBV-HCC). A total of 3128 participants met the inclusion and exclusion criteria for this study. 20 polymorphic loci on MSH2, MSH3 and MSH6 were selected for genotyping. There were four case-control studies, which were HC vs. HCC, SC vs. HCC, CHB vs. HCC and LC vs. HCC. We used Hardy-Weinberg equilibrium test, unconditional logistic regression, haplotype analysis, and gene-gene interaction for genetic analysis. Ultimately, after excluding confounding factors such as age, gender, smoking and drinking, 12 polymorphisms were found to be associated with genetic susceptibility to HCC. Haplotype analysis showed the risk haplotype GTTT (rs1805355_G, rs3776968_T, rs1428030_C, rs181747_C) was more frequent in the HCC group compared with the HC group. The GMDR analysis showed that the best interaction model was the three-factor model of MSH2-rs1981928, MSH3-rs26779 and MSH6-rs2348244 in SC vs. HCC group (P=0.001). In addition, we found multiplicative or additive interactions between genes in our selected SNPs. These findings provide new ideas to further explore the etiology and pathogenesis of HCC. We have attempted to explain the molecular mechanisms by which certain SNPs (MSH2-rs4952887, MSH3-rs26779, MSH3-rs181747 and MSH3-rs32950) affect genetic susceptibility to HCC from the perspectives of eQTL, TFBS, cell cycle and so on. We also explained the results of haplotypes and gene-gene interactions. These findings provide new ideas to further explore the etiology and pathogenesis of HCC.

Prioritization and Meta-analysis of regulatory SNPs identified IL6, TGFB1, TLR9 and MMP7 as significantly associated with cervical cancer

Cervical cancer is a leading women cancer globally with respect to both incidence and mortality. Its increased risk has been linked with HPV infection and genetic variations like single nucleotide polymorphisms (SNPs). Although, studies have been published which evaluates the effect of SNPs in a few candidate genes, however the role of number of regulatory SNPs (rSNPs) in cervical cancer is not available. As literature evidence has shown that non-coding rSNPs are related with increasing cervical cancer risk, we undertook this study to prioritize the important rSNPs and elucidate their role. A search was conducted in PubMed up to December 2020, which led to the identification of 263 articles and 969 SNPs in the non-coding region. These 969 SNPs were analysed through rSNPBase and RegulomeDB, leading to identification of 105 rSNPs. Afterwards, a regulatory module was constructed using protein-protein interaction data and a hub of highly interacting 23 target genes (corresponding to 34 rSNPs) was identified using MCODE. To further understand the mechanism of action of the 34 rSNPs, their transcription factor information with respect to cervical cancer was retrieved. To evaluate the pooled effect of these prioritized polymorphisms in cervical cancer patients, a meta-analysis was performed on 10,537 cases and 11,252 controls from 30 studies corresponding to 8 rSNPs. It led to identification of polymorphisms in IL6 (rs2069837), TGFB1 (rs1800469), TLR9 (rs187084) and MMP7 (rs11568818) which are significantly (p < 0.05) associated with increased cervical cancer risk at the population level. Overall, the study demonstrates that rSNPs targeting immune and inflammatory genes (IL1B, IL6, IL10, IL18, TGFB1, CCR5, CD40, TLR9, and MMP7) are associated with cervical cancer.

An intron SNP rs2069837 in IL-6 is associated with osteonecrosis of the femoral head development

Background

Genetic polymorphisms play a crucial role in the development of osteonecrosis of the femoral head (ONFH). This study mainly explored the association of IL-6 variants and ONFH susceptibility among the Chinese Han population.

Methods

Two variants (rs2069837, and rs13306435) in the IL-6 gene were identified and genotyped from 566 patients with ONFH and 566 healthy controls. The associations between IL-6 polymorphisms and ONFH susceptibility were assessed using odds ratio (OR) and 95% confidence interval (95% CI) via logistic regression. The potential function of these two variants was predicted by the HaploReg online database.

Results

The results of the overall analysis revealed that IL-6 rs2069837 was correlated with decreased risk of ONFH among the Chinese Han population (p < 0.05). In stratified analysis, rs2069837 also reduced the susceptibility to ONFH in older people (> 51 years), males, nonsmokers, and nondrinkers (p < 0.05). However, no associations between rs13306435 and ONFH susceptibility were observed (p > 0.05).

Conclusions

To sum up, we suggested that rs2069837 G>A polymorphism in the IL-6 gene was significantly associated with a decreased risk of ONFH among the Chinese Hans. These findings underscored the crucial role of IL-6 rs2069837 in the occurrence of ONFH.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-021-01142-3.

Analysis of association between MALAT1 haplotype and the severity of normal-tension glaucoma (NTG)

MALAT1, which is disorderly expressed in the growth, invasion, migration and cancer cell apoptosis, was shown to be associated with normal-tension glaucoma (NTG), a type of optic neuropathy. The haplotype in MALAT1 affects its expression and is correlated with human diseases like normal-tension glaucoma (NTG). However, the underlying detailed mechanism remains unclear. In this study, we aimed to analyse the association between MALAT1 haplotype and the severity of NTG in a molecular level. Quantitative real-time PCR, ELISA and luciferase assays were performed to establish the underlying signalling pathways. RNFL thickness, RA and C/D ratio were calculated for NTG patients. Accordingly, GGGT haplotype was demonstrated to be associated with a decreased risk of NTG. The MALAT1 level in serum of NTG patients carrying GGGT haplotype was significantly decreased compared with NTG patients carrying other haplotypes, along with elevated miR-1 expression and diminished IL-6 expression. NTG patients carrying GGGT haplotype had thicker RNFL and RA, but a smaller C/D ratio. Sequence analysis found potential target sites of miR-1 on MALAT1 and IL-6, and luciferase assay confirmed the inhibitory effect of miR-1 on MALAT1 and IL-6 expression. Meanwhile, MALAT1 also down-regulated miR-1 expression and consequently up-regulated IL-6 expression. This study presented evidence for a regulatory network containing MALAT1, miR-1 and IL-6, and further demonstrated the effect of MALAT1 haplotype on the risk and severity of NTG.

Polymorphisms of the Highly Expressed IL-6 Gene in the Papillary Thyroid Cancer Susceptibility Among Chinese

BACKGROUND

Papillary thyroid cancer (PTC) is the cardinal histologic type of thyroid cancer, which is the most prevalent kind of endocrine malignancy. The expression of IL-6 is found higher in thyroid carcinoma (THCA) samples than paired normal tissues based on The Cancer Genome Atlas (TCGA) and Genotype-Tissue expression (GTEx) database. In this study, we aimed to investigate the association between interleukin-6 (IL-6) polymorphisms and the PTC risk.

METHODS

A case-control study was designed using the following data: 241 PTC patients and 463 healthy controls. Five single nucleotide polymorphisms (SNPs) in IL-6 were selected and genotyped using Agena MassARRAY technology.

RESULTS

Our results revealed that SNP rs1800796 was associated with an increased PTC risk in co-dominant model (p = 0.042) and dominant model (p = 0.027). Rs1524107 was also a risk factor for PTC susceptibility in co-dominant model (p = 0.003), dominant model (p = 0.002) and log-additive model (p = 0.044). Moreover, rs2066992 significantly increased the PTC risk in co-dominant model and dominant model (p = 0.011, p = 0.009, respectively). Additionally, rs2069837 variant elevated the PTC risk based on dominant model (p = 0.041). In silico analysis, GTEx results for rs1800796, rs1524107 and rs2066992 variants are known to be associated with IL-6 gene expression. Using HaploReg, we found rs1800796, rs1524107 and rs2066992 in LD with functional importance.

CONCLUSION

Our study indicates that IL-6 variants may be a risk factor involved in the pathogenesis and development of PTC.

Association of Polymorphisms in Cytokine genes with susceptibility to Precancerous Lesions and Cervical Cancer: A systematic review with meta-analysis

Objectives: This study investigated the relationship between single-nucleotide polymorphisms (SNPs) in cytokine genes and the susceptibility to Squamous Intraepithelial Lesions (SIL), cervical cancer and HPV infection through a systematic review with meta-analysis. To verify the effect of SNPs, we also analyzed the transcription factor binding affinity using bioinformatics tools.Methods: Seven electronic databases (MEDLINE, Scielo, BIREME, PubMed, Scopus, Web of Science and Science Direct) were searched for case-control studies.Results: A total of 35 relevant case-control studies were meta-analyzed, including 7 cytokine genes and 15 SNPs. SNPs in IL-17A (rs2275913, rs3748067); IL-17 F (rs763780); IL-12A (rs568408); IL-12B (rs3212227); TNFA (rs1800629, rs361525); IL-1B (rs16944); IL-6 (rs1800795); IL-10 (rs1800896) genes were associated with increased risk for cervical cancer. No association was observed between meta-analyzed polymorphisms and SIL. Additional bioinformatics analysis suggested a possible transcriptional regulation pathway of the TNFA and IL-10 genes through the MZF1 (TNFA -308 G > A and IL-10 - 1082A>G) and ZNF263 (TNFA -238 G > A) transcription factors binding.Conclusion: Overall, 10 SNPs in cytokine genes were associated with increased risk for cervical cancer. Therefore, in our meta-analysis, these SNPs demonstrated to be potential biomarkers for predicting or identifying cases of high risk for SIL and cervical cancer.

Association between HER2 and IL-6 genes polymorphisms and clinicopathological characteristics of breast cancer: significant role of genetic variability in specific breast cancer subtype

Clinical implications of single nucleotide polymorphisms (SNPs) in breast cancer have been explored to determine the impact of SNP in modulating the pathogenesis of breast cancer. This study aimed to evaluate the association between HER2 (rs2517956) and (IL-6) (rs1800795 and rs2069837) and clinicopathological characteristics in HER2-positive and HER2-negative breast cancer in Tunisian women. A retrospective cohort study included 273 patients. Genomic DNA was extracted from peripheral blood samples, and genotyping of selected SNP was performed by PCR-RFLP assays. Statistical analysis was then carried out to assess genotypic frequencies and genetic association in relation to breast cancer subtypes. SHEsis software was applied to IL-6 haplotypic structure analysis. The distribution of genotype frequencies of rs2517956, rs1800795 and rs2069837 showed no statistically difference between HER2-positive and HER2-negative breast cancer. HER2 (rs2517956) was associated with tumor size (p = 0.01) and age at diagnosis (p = 0.02) in HER2-negative breast cancers, but no significant association was observed in HER2-positive breast cancer. For IL-6 gene, none of the clinicopathological parameters were associated with rs1800795 and rs2069837 in both breast cancer subtypes (p > 0.05). SHEsis analysis revealed a high linkage disequilibrium between rs1800795 and rs2069837; differences in the distribution of IL-6 two loci haplotypes were statistically negative between HER2-positive and HER2-negative breast cancer (p = 0.20) which confirmed no association with HER2 overexpression. This study demonstrates that rs2517956 is associated with clinicopathological characteristics in HER2-negative breast cancer, which could have a differential prognostic role compared to HER2-positive breast cancer.

Association of IL-12B rs3212227 and IL-6 rs1800795 Polymorphisms with Susceptibility to Cervical Cancer: A Systematic Review and Meta-Analysis

Background:

Primary studies have shown that the IL-12B rs3212227 and IL-6 rs1800795 polymorphisms are associated with an increased risk of cervical cancer. However, conflicting results warrant a meta-analysis to obtain more precise estimates.

Methods:

A comprehensive literate search on PubMed, Web of Science, Scopus, CNKI, and SciELO was performed to collect all eligible studies up to November 10, 2019. The pooled odds ratios (OR) and 95% confidence intervals (CI) were used to calculate the risk. This meta-analysis was carried out by utilizing CMA software.

Results:

A total of eleven case-control studies including four studies on IL-12B rs3212227 and seven studies on IL-6rs1800795 were selected. Pooled ORs revealed that the IL-6 rs1800795 polymorphism was significantly associated with an increased risk of cervical cancer (C vs. G: OR = 1.294, 95% CI 1.071-1.564, p= 0.007; CC vs. GG: OR = 1.633, 95% CI 1.059-2.520, p= 0.027; CC+CG vs. GG: OR = 1.312, 95% CI 1.048-1.643, p= 0.018; and CC vs. CG+GG: OR = 1.592, 95% CI 1.268-1.999, p≤0.001), but not IL-12B rs3212227 polymorphism. Stratified analysis by ethnicity revealed that both IL-12B rs3212227 and IL-6 rs1800795 polymorphisms were associated with risk of cervical cancer in Asian women.

Conclusions:

Our pooled data revealed that the IL-12B rs3212227 and IL-6 rs1800795 polymorphisms may be used to identify individuals at high risk of cervical cancer in Asian women.

Genetic polymorphisms of interleukin-6 influence the development of hepatitis B virus-related liver cirrhosis in the Han Chinese population

BACKGROUND

Interleukin-6 (IL-6) plays an important role in chronic inflammation. Thus, we aimed to investigate the effects of IL-6 polymorphisms on predicting the progression of hepatitis B virus (HBV)-r elated liver cirrhosis.

METHODS

A cross-sectional study was conducted to analyse IL-6 polymorphisms and serum levels of IL-6 in HBV-infected patients at different clinical phases and in healthy controls. IL-6 polymorphisms were detected by the TaqMan PCR method, and plasma IL-6 levels were assessed by ELISA.

RESULTS

Our analysis included 182 chronic hepatitis B (CHB) patients, 190 HBV-infected liver cirrhosis cases, 125 inactive HBsAg carriers, and 246 healthy controls. Seven SNPs in IL-6 including rs10499563, rs17147230, rs1800796, rs2069837, rs1524107, rs2066992, and rs2069852 were analysed. In a haplotype analysis between HBV-infected liver cirrhosis cases and CHB patients, inactive HBV carriers or healthy controls, haplotype CT in block 1 and haplotype GGCGG in block 2 were associated with liver cirrhosis (P <0.05). Moreover, the genotype or allele frequencies were significantly different in IL-6 rs10499563 and rs2069837 when HBV-infected liver cirrhosis patients were compared with CHB patients, inactive HBV carriers or healthy controls. A further study found that compared with that in the healthy controls, inactive HBV carriers or CHB patients, plasma IL-6 was elevated in HBV-infected liver cirrhosis patients.

CONCLUSION

In conclusion, the IL-6 rs10499563 and rs2069837 polymorphisms are associated with incidence of liver cirrhosis may through their effects on IL-6 expression and these two single nucleotide polymorphisms can be used as potential prognostic markers of HBV-related liver cirrhosis.

Takayasu arteritis risk locus in IL6 represses the anti-inflammatory gene GPNMB through chromatin looping and recruiting MEF2-HDAC complex

OBJECTIVE

Previous work has revealed a genetic association between Takayasu arteritis and a non-coding genetic variant in an enhancer region within IL6 (rs2069837 A/G). The risk allele in this variant (allele A) has a protective effect against chronic viral infection and cancer. The goal of this study was to characterise the functional consequences of this disease-associated risk locus.

METHODS

A combination of experimental and bioinformatics tools were used to mechanistically understand the effects of the disease-associated genetic locus in IL6. These included electrophoretic mobility shift assay, DNA affinity precipitation assays followed by mass spectrometry and western blotting, luciferase reporter assays and chromosome conformation capture (3C) to identify chromatin looping in the IL6 locus. Both cell lines and peripheral blood primary monocyte-derived macrophages were used.

RESULTS

We identified the monocyte/macrophage anti-inflammatory gene GPNMB,~520 kb from IL6, as a target gene regulated by rs2069837. We revealed preferential recruitment of myocyte enhancer factor 2-histone deacetylase (MEF2-HDAC) repressive complex to the Takayasu arteritis risk allele. Further, we demonstrated suppression of GPNMB expression in monocyte-derived macrophages from healthy individuals with AA compared with AG genotype, which was reversed by histone deacetylase inhibition. Our data show that the risk allele in rs2069837 represses the expression of GPNMB by recruiting MEF2-HDAC complex, enabled through a long-range intrachromatin looping. Suppression of this anti-inflammatory gene might mediate increased susceptibility in Takayasu arteritis and enhance protective immune responses in chronic infection and cancer.

CONCLUSIONS

Takayasu arteritis risk locus in IL6 might increase disease susceptibility by suppression of the anti-inflammatory gene GPNMB through chromatin looping and recruitment of MEF2-HDAC epigenetic repressive complex. Our data highlight long-range chromatin interactions in functional genomic and epigenomic studies in autoimmunity.

Association Between MALAT1 and THRIL Polymorphisms and Precancerous Cervical Lesions

BACKGROUND

The occurrence of cervical cancer is a complex process, for which human papillomavirus (HPV) infection is a risk factor, although not all women infected with HPV will develop the disease. Knockout of mammalian lung metastasis associated transcript 1 (MALAT1) is associated with increased risk for several cancer types, whereas the long non-coding RNA (lncRNA) THRIL is essential for induction of tumor necrosis factor-α expression, which plays important roles in HPV infection.

MATERIALS AND METHODS

To investigate the effects of polymorphisms in the lncRNAs MALAT1 and THRIL on the susceptibility to precancerous cervical lesions, 12 single nucleotide polymorphisms (SNPs) were analyzed from 164 cervical precancerous lesion cases and 428 controls. Gene-gene and gene-environment interactions and haplotype associations were also evaluated.

RESULTS

We found a significantly decreased risk of precancerous cervical lesions for the THRIL rs7133268 AG genotype (odds ratio adjusted = 0.63, 95% confidence interval: 0.42-0.94, p = 0.025). Multifactor dimensionality reduction analysis identified a significant two-locus interaction model involved in HPV infection and THRIL rs7133268 (training balanced accuracy = 0.6957, testing balanced accuracy = 0.6948, cross-validation consistency = 10/10, p = 0.0046). Other SNPs, including the two identified for MALAT1, were not significantly related to the risk of precancerous cervical lesions.

CONCLUSION

Our results suggest that the rs7133268 polymorphism of the lncRNA THRIL gene can reduce the genetic susceptibility of precancerous cervical lesions and in turn reduce the risk of HPV infection.

Associations of potentially functional variants in IL-6, JAKs and STAT3 with gastric cancer risk in an eastern Chinese population

The interleukin-6 (IL-6)/JAK/STAT3 signaling pathway plays a central role in inflammation-mediated cancers, including gastric cancer (GCa). We evaluated associations between 10 potentially functional single nucleotide polymorphisms (SNPs) of four essential genes in the pathway and GCa risk in a study of 1,125 GCa cases and 1,221 cancer-free controls. We found that a significant higher GCa risk was associated with IL-6 rs2069837G variant genotypes [adjusted odds ratios (OR) = 1.33; 95% confidence interval (CI) = 1.12-1.59 for AG + GG vs. AA)] and JAK1 rs2230587A variant genotypes (adjusted OR = 1.20; 95% CI = 1.02-1.43 for GA + AA vs. GG). We also found that a significant decreased GCa risk was associated with STAT3 rs1053004G variant genotypes (adjusted OR = 0.84; 95% CI = 0.71-0.99 for AG + GG vs. AA). The combined analysis of IL-6 rs2069837G and JAK1 rs2230587A variant risk genotypes revealed that individuals with one-or-two risk genotypes exhibited an increased risk for GCa (adjusted OR = 1.34; 95% CI = 1.13-1.59). Genotypes and mRNA expression correlation analysis using the data from the HapMap 3 database provided further support for the observed risk associations. Larger studies are warranted to validate these findings.

Exposure to Traffic-Related Air Pollution and Serum Inflammatory Cytokines in Children

BACKGROUND

Long-term exposure to ambient air pollution can lead to adverse health effects in children; however, underlying biological mechanisms are not fully understood.

OBJECTIVES

We evaluated the effect of air pollution exposure during different time periods on mRNA expression as well as circulating levels of inflammatory cytokines in children.

METHODS

We measured a panel of 10 inflammatory markers in peripheral blood samples from 670 8-y-old children in the Barn/Child, Allergy, Milieu, Stockholm, Epidemiology (BAMSE) birth cohort. Outdoor concentrations of nitrogen dioxide (NO₂) and particulate matter (PM) with aerodynamic diameter <10 μm (PM₁₀) from road traffic were estimated for residential, daycare, and school addresses using dispersion modeling. Time-weighted average exposures during infancy and at biosampling were linked to serum cytokine levels using linear regression analysis. Furthermore, gene expression data from 16-year-olds in BAMSE (n=238) were used to evaluate links between air pollution exposure and expression of genes coding for the studied inflammatory markers.

RESULTS

A 10 μg/m³ increase of NO₂ exposure during infancy was associated with a 13.6% (95% confidence interval (CI): 0.8; 28.1%) increase in interleukin-6 (IL-6) levels, as well as with a 27.8% (95% CI: 4.6, 56.2%) increase in IL-10 levels, the latter limited to children with asthma. However, no clear associations were observed for current exposure. Results were similar using PM₁₀, which showed a high correlation with NO₂. The functional analysis identified several differentially expressed genes in response to air pollution exposure during infancy, including IL10, IL13, and TNF;.

CONCLUSION

Our results indicate alterations in systemic inflammatory markers in 8-y-old children in relation to early-life exposure to traffic-related air pollution. https://doi.org/10.1289/EHP460.

Multiple functional SNPs in differentially expressed genes modify risk and survival of non-small cell lung cancer in Chinese female non-smokers

DNA genotype can affect gene expression, and gene expression can influence the onset and progression of diseases. Here we conducted a comprehensive study, we integrated analysis of gene expression profile and single nucleotide polymorphism (SNP) microarray data in order to scan out the critical genetic changes that participate in the onset and development of non-small cell lung cancer (NSCLC). Gene expression profile datasets were downloaded from the GEO database. Firstly, differentially expressed genes (DEGs) between NSCLC samples and adjacent normal samples were identified. Next, by STRING database, protein-protein interaction (PPI) network was constructed. At the same time, hub genes in PPI network were identified. Then, some functional SNPs in hub genes that may affect gene expression have been annotated. Finally, we carried a study to explore the relationship between functional SNPs and NSCLC risk and overall survival in Chinese female non-smokers. A total of 488 DEGs were identified in our study. There are 29 proteins with a higher degree of connectivity in the PPI network, including FOS, IL6 and MMP9. By using database annotation, we got 8 candidate functional SNPs that may affect the expression level of hub proteins. In the case-control study, we found that rs4754-T allele, rs959173-C allele and rs2239144-G allele were the protective allele of NSCLC risk. In dominant model, rs4754-CT+TT genotype were associated with a shorter survival time. In general, our study provides a novel research direction in the field of multi-omic data integration, and helps us find some critical genetic changes in disease.

Cervical Carcinogenesis and Immune Response Gene Polymorphisms: A Review

The local immune response is considered a key determinant in cervical carcinogenesis after persistent infection with oncogenic, high-risk human papillomavirus (HPV) infections. Genetic variation in various immune response genes has been shown to influence risk of developing cervical cancer, as well as progression and survival among cervical cancer patients. We reviewed the literature on associations of immunogenetic single nucleotide polymorphism, allele, genotype, and haplotype distributions with risk and progression of cervical cancer. Studies on HLA and KIR gene polymorphisms were excluded due to the abundance on literature on that subject. We show that multiple genes and loci are associated with variation in risk of cervical cancer. Rather than one single gene being responsible for cervical carcinogenesis, we postulate that variations in the different immune response genes lead to subtle differences in the effectiveness of the antiviral and antitumour immune responses, ultimately leading to differences in risk of developing cervical cancer and progressive disease after HPV infection.

Relationships between Common and Novel Interleukin-6 Gene Polymorphisms and Risk of Cervical Cancer: a Case-Control Study

We investigated the association between six common and novel interleukin-6 (IL-6) polymorphisms with the risk of cervical cancer (CC) among Tunisians. Study subjects comprised 112 CC cases and 164 control women. Genotyping of IL-6 rs2069845, rs2069840, rs1474348, rs1800795, rs1800797, rs2069827 variants was done by real-time PCR, with defined clusters. The allelic and genotypic distributions of the tested IL-6 SNPs were comparable between CC patients and control women. Stratification according to FIGO staging revealed that rs1800795 homozygous major allele genotype (P = 0.033; OR =0.49(0.25-0.95)) and major allele (P = 0.037; OR = 0.57 (0.33-0.97)) were protective of CC. Moreover, carriage of rs1474348 major allele was also protective of CC (P = 0.014; OR = 0.53(0.32-0.88)), while higher rs1474348 minor allele frequency was seen in CC patients with early FIGO stage (P = 0.044; OR = 0.39 (0.15-1.00)), thus implicating rs1474348 in CC evolution and progression of angiogenesis. Haploview analysis demonstrated high linkage disequilibrium (LD) between rs2069845, rs2069840, rs1474348 and rs1800795, and 6-locus haplotype analysis identified GACCCA haplotype to be positively associated with increased CC, while GAGGGG haplotype was negatively associated with CC, thus suggesting a protective role for this haplotype in CC. Furthermore, there was a significant association between the incidence of CC and the use hormonal contraception (P = 0.047; OR = 1.97 (0.94-4.13)) and smoking (P < 0.001; OR = 7.12 (2.97-17.04)). The IL-6 variants rs1800795 and rs1474348, and haplotypes GACCCA and GAGGGG, along with use of hormonal contraceptives and smoking, are major risk factors of CC susceptibility and evolution among Tunisian women.

Risk allelic load in Th2 and Th3 cytokines genes as biomarker of susceptibility to HPV-16 positive cervical cancer: a case control study

Background

Alterations in the host cellular immune response allow persistent infections with High-Risk Human Papillomavirus (HR-HPV) and development of premalignant cervical lesions and cervical cancer (CC). Variations of immunosuppressive cytokine levels in cervix are associated with the natural history of CC. To assess the potential role of genetic host immunity and cytokines serum levels in the risk of developing CC, we conducted a case–control study paired by age.

Methods

Peripheral blood samples from patients with CC (n = 200) and hospital controls (n = 200), were used to evaluate nine biallelic SNPs of six cytokine genes of the adaptive immune system by allelic discrimination and cytokines serum levels by ELISA.

Results

After analyzing the SNP association by multivariate logistic regression adjusted by age, CC history and smoking history, three Th2 cytokines (IL-4, IL-6 and IL-10) and one Th3 (TGFB1) cytokine were significantly associated with CC. Individuals with at least one copy of the following risk alleles: T of SNP (−590C > T IL-4), C of SNP (−573G > C IL-6), A of SNP (−592C > A IL-10), T of SNP (−819C > T IL-10) and T of SNP (−509C > T TGFB1), had an adjusted odds ratio (OR) of 2.08 (95 % CI 1.475–2.934, p = 0.0001), an OR of 1.70 (95 % CI 1.208–2.404, p = 0.002), an OR of 1.87 (95 % CI 1.332–2.630, p = 0.0001), an OR of 1.67 (95 % CI 1.192–2.353, p = 0.003) and an OR of 1.91 (95 % CI 1.354–2.701, p = 0.0001), respectively, for CC. The burden of carrying two or more of these risk alleles was found to have an additive effect on the risk of CC (p trend = 0.0001). Finally, the serum levels of Th2 and Th3 cytokines were higher in CC cases than the controls; whereas IFNG levels, a Th1 cytokine, were higher in controls than CC cases.

Conclusion

The significant associations of five SNPs with CC indicate that these polymorphisms are potential candidates for predicting the risk of development of CC, representing a risk allelic load for CC and can be used as a biomarker of susceptibility to this disease.

Prognostic Impact of IL6 Genetic Variants in Patients with Metastatic Colorectal Cancer Treated with Bevacizumab-Based Chemotherapy

PURPOSE

The IL6/STAT3 axis promotes inflammation, angiogenesis, and cancer. The effect of genetic variants within this pathway on benefit from antiangiogenic cancer therapy is unknown. We tested whether SNPs in genes involved in IL6/STAT3 signaling can predict efficacy of bevacizumab-based chemotherapy in metastatic colorectal cancer (mCRC) patients.

EXPERIMENTAL DESIGN

Associations between potentially functional IL6 (rs2069837 and rs1800795) and STAT3 (rs744166 and rs4796793) SNPs and clinical outcomes [progression-free survival (PFS), overall survival, and tumor response rate] were evaluated in mCRC patients receiving first-line FOLFIRI plus bevacizumab in two randomized phase III trials: TRIBE (n = 223, training cohort) and FIRE-3 (n = 288, validation cohort). Patients receiving FOLFIRI plus cetuximab in FIRE-3 (n = 264) served as a control cohort. The interaction between genotype and primary tumor location with clinical outcomes was examined. Genomic DNA isolated from whole blood or tumor tissue was analyzed by PCR-based direct sequencing.

RESULTS

Patients with an IL6 rs2069837 G allele treated with FOLFIRI plus bevacizumab had an inferior PFS than those with the A/A genotype in TRIBE [9.4 vs. 11.1 months; HR = 1.53; 95% confidence interval (CI), 1.12-2.10; P = 0.004] and FIRE-3 (8.8 vs. 10.9 months; HR = 1.40; 95% CI, 1.06-1.85; P = 0.015). These associations were confirmed in multivariable analyses and were not seen in the control cohort. In subgroup analysis, the effect of IL6 rs2069837 on PFS was present only in patients with left-sided cancers, but the test for interaction was not significant.

CONCLUSIONS

IL6 rs2069837 genotype is a clinically relevant prognostic factor in mCRC patients treated with first-line bevacizumab-based chemotherapy. Clin Cancer Res; 22(13); 3218-26. ©2016 AACR.

Network Topologies Decoding Cervical Cancer

According to the GLOBOCAN statistics, cervical cancer is one of the leading causes of death among women worldwide. It is found to be gradually increasing in the younger population, specifically in the developing countries. We analyzed the protein-protein interaction networks of the uterine cervix cells for the normal and disease states. It was found that the disease network was less random than the normal one, providing an insight into the change in complexity of the underlying network in disease state. The study also portrayed that, the disease state has faster signal processing as the diameter of the underlying network was very close to its corresponding random control. This may be a reason for the normal cells to change into malignant state. Further, the analysis revealed VEGFA and IL-6 proteins as the distinctly high degree nodes in the disease network, which are known to manifest a major contribution in promoting cervical cancer. Our analysis, being time proficient and cost effective, provides a direction for developing novel drugs, therapeutic targets and biomarkers by identifying specific interaction patterns, that have structural importance.

Stratification analysis and case-control study of relationships between interleukin-6 gene polymorphisms and cervical cancer risk in a Chinese population

Interleukin-6 (IL-6), a central proinflammatory cytokine, maintains immune homeostasis and also plays important roles in cervical cancer. Therefore, we aimed to evaluate any associations of IL-6 gene polymorphisms at positions -174 and -572 with predisposition to cervical cancer in a Chinese population. The present hospital- based case-control study comprised 518 patients with cervical cancer and 518 healthy controls. Polymorphisms of the IL-6 gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Patients with cervical cancer had a significantly higher frequency of the IL-6 -174 CC genotype [odds ratio (OR) =1.52, 95% confidence interval (CI) = 1.06-2.19; p=0.02], IL-6 -572 CC genotype (OR =1.91, 95% CI = 1.16-3.13; p=0.01) and IL-6 -174 C allele (OR =1.21, 95% CI = 1.02-1.44; p=0.03) compared to healthy controls. When stratifying by the FIGO stage, patients with III-IV cervical cancer had a significantly higher frequency of IL-6 -174 CC genotype (OR =1.64, 95% CI =1.04-2.61; p=0.04). The CC genotypes of the IL-6 gene polymorphisms at positions -174 and -572 may confer a high risk of cervical cancer. Additional studies with detailed human papillomavirus (HPV) infection data are warranted to validate our findings.

Polymorphisms in the kinesin-like factor 1 B gene and risk of epithelial ovarian cancer in Eastern Chinese women

The kinesin-like factor 1 B (KIF1B) gene plays an important role in the process of apoptosis and the transformation and progression of malignant cells. Genetic variations in KIF1B may contribute to risk of epithelial ovarian cancer (EOC). In this study of 1,324 EOC patients and 1,386 cancer-free female controls, we investigated associations between two potentially functional single nucleotide polymorphisms in KIF1B and EOC risk by the conditional logistic regression analysis. General linear regression model was used to evaluate the correlation between the number of variant alleles and KIF1B mRNA expression levels. We found that the rs17401966 variant AG/GG genotypes were significantly associated with a decreased risk of EOC (adjusted odds ratio (OR) = 0.81, 95 % confidence interval (CI) = 0.68-0.97), compared with the AA genotype, but no associations were observed for rs1002076. Women who carried both rs17401966 AG/GG and rs1002076 AG/AA genotypes of KIF1B had a 0.82-fold decreased risk (adjusted 95 % CI = 0.69-0.97), compared with others. Additionally, there was no evidence of possible interactions between about-mentioned co-variants. Further genotype-phenotype correlation analysis indicated that the number of rs17401966 variant G allele was significantly associated with KIF1B mRNA expression levels (P for GLM = 0.003 and 0.001 in all and Chinese subjects, respectively), with GG carriers having the lowest level of KIF1B mRNA expression. Taken together, the rs17401966 polymorphism likely regulates KIF1B mRNA expression and thus may be associated with EOC risk in Eastern Chinese women. Larger, independent studies are warranted to validate our findings.

Down-regulation of microRNA-9 leads to activation of IL-6/Jak/STAT3 pathway through directly targeting IL-6 in HeLa cell

MicroRNA‐9 (miR‐9) presents to exert distinct and even opposite functions in different kinds of tumors through targeting different cellular genes. However, its role in cervical adenocarcinoma remains uncertain. Here, we report that miR‐9 is down‐regulated in cervical adenocarcinoma due to its frequent promoter‐hypermethylation and exerts its tumor suppressor role through inhibiting several novel target genes, including interleukin‐6 (IL‐6). The promoters of miR‐9 precursors (mir‐9‐1, ‐2, and ‐3) were hypermethylated in cervical adenocarcinoma tissues. Demethylation treatment of HeLa dramatically increased the expression of mature miR‐9. Both in vitro and in vivo functional experiments confirmed that miR‐9 can inhibit the proliferation, migration, and malignant transformation abilities of HeLa cells. Bioinformatics methods and array‐based RNA expression profiles were used to screen the downstream target genes of miR‐9. Dual‐luciferase reporting assay, real‐time qPCR, and ELISA or Western blot confirmed four genes (CKAP2, HSPC159, IL‐6, and TC10) to be novel direct target genes of miR‐9. Pathway annotation analysis of the differently expressed genes (DEGs) induced by ectopic miR‐9 expression revealed the enrichment in Jak/STAT3 pathway, which is one of the downstream pathways of IL‐6. Ectopic expression of miR‐9 in HeLa inhibited Jak/STAT3 signaling activity. Moreover, such effect could be partially reversed by the addition of exogenous IL‐6. In conclusion, our results here present a tumor suppressor potential of miR‐9 in cervical adenocarcinoma for the first time and suggest that miR‐9 could repress tumorigenesis through inhibiting the activity of IL‐6/Jak/STAT3 pathway. © 2015 The Authors. Molecular Carcinogenesis, published by Wiley Periodicals, Inc.

CASP7 variants modify susceptibility to cervical cancer in Chinese women

Polymorphisms in Caspase-7 (CASP7) may modulate the programmed cell death and thus contribute to cervical cancer risk. In this case-control study of 1,486 cervical cancer cases and 1,301 controls, we investigated associations between four potentially functional polymorphisms in CASP7 and cervical cancer risk and evaluated their locus-locus interaction effects on the risk. The genotype-phenotype correlation was performed by a generalized linear regression model. We found that the rs4353229 polymorphism was associated with cervical cancer risk (under a recessive model: crude OR = 1.20, 95% CI = 1.02-1.40). Compared with the TT genotype, the rs10787498GT genotype was associated with an increased cervical cancer risk (adjusted OR = 1.19, 95% CI = 1.00-1.41). Combination analysis showed that subjects with four putative risk genotypes had a 1.54-fold increased cancer risk, compared with those who carried three or less putative risk genotypes. We also observed significant locus-locus joint effects on the risk, which may be mediated by the polymorphisms regulating CASP7 mRNA expression. Subsequent multifactor dimensionality reduction and classification and regression tree analyses indicated that the CASP7 genotypes might have a locus-locus interaction effect that modulated cervical cancer risk. Out data suggest that CASP7 polymorphisms may interact to modify cervical cancer risk by a possible mechanism of regulating CASP7 mRNA expression.

Association between six genetic variants of IL-17A and IL-17F and cervical cancer risk: a case-control study

We conducted a case-control study to estimate association between six common single nucleotide polymorphisms (SNPs) and risk of cervical cancer and evaluate the interaction between IL-17 gene polymorphisms and environmental factors in cervical cancer patients. This study included 264 consecutive primary cervical cancer patients and 264 age-matched controls. The genotypes of IL-17A rs2275913, rs3748067, and rs3819025 and IL-17A rs763780, rs9382084, and rs1266828 were analyzed using polymerase chain reaction-restriction fragment length of polymorphism (PCR-RFLP) assay. By logistic regression analysis, we found that individuals with AA genotype of rs2275913 were correlated with increased risk of cervical cancer when compared with GG genotype, and the odds ratio (OR) (95 % confidence interval (CI)) for AA genotype was 2.34 (1.24-4.49). By stratified analysis, individuals with AA genotype of rs2275913 were significantly associated with increased risk of cervical cancer in HPV-16- or HPV-18-infected patients when compared with GG genotype, and the OR (95 % CI) was 4.11 (1.14-22.33). In this case-control study, we suggest that rs2275913 may play an important role in the development of cervical cancer, especially in HPV-16- or HPV-18-infected patients.

Lessons and implications from association studies and post-GWAS analyses of cervical cancer

Cervical cancer has a heritable genetic component. A large number of genetic associations with cervical cancer have been reported in hypothesis-driven candidate gene studies, but many of these results are either inconsistent or have failed to be independently replicated. Genome-wide association studies (GWAS) have identified additional susceptibility loci previously not implicated in cervical cancer development, highlighting the power of genome-wide unbiased association analyses. Post-GWAS analyses including pathway-based analysis and functional characterization of associated variants have provided new insights into the pathogenesis of cervical cancer. In this review we summarize findings from candidate gene association studies, GWAS, and post-GWAS analyses of cervical cancer. We also discuss gaps in our understanding, possible clinical implications of the findings, and lessons for studies of other complex diseases.

Association between the PARP1 Val762Ala polymorphism and cancer risk: evidence from 43 studies

BACKGROUND

Poly (ADP-ribose) polymerase-1 (PARP-1) plays critical roles in the detection and repair of damaged DNA, as well as cell proliferation and death. Numerous studies have examined the associations between PARP1 Val762Ala (rs1136410 T>C) polymorphism and cancer susceptibility; nevertheless, the findings from different research groups remain controversial.

METHODS

We searched literatures from MEDLINE, EMBASE and CBM pertaining to such associations, and then calculated pooled odds ratio (OR) and 95% confidence interval (CI) by using random-effects model. The false-positive report probability (FPRP) analysis was used to confirm the validity of significant findings. Moreover, potential effects of rs1136410 variants on PARP1 mRNA expression were analyzed for three ethnicities by combining data from HapMap (genotype) and SNPexp (mRNA expression).

RESULTS

The final meta-analysis incorporated 43 studies, consisting of 17,351 cases and 22,401 controls. Overall, our results did not suggest significant associations between Ala variant (Ala/Ala or Ala/Val genotype) and cancer risk. However, further stratification analysis showed significantly increased risk for gastric cancer (Ala/Ala vs. Val/Val: OR = 1.56, 95% CI = 1.01-2.42, Ala/Val vs. Val/Val: OR = 1.34, 95% CI = 1.14-1.58, dominant model: OR = 1.41, 95% CI = 1.21-1.65 and Ala vs. Val: OR = 1.29, 95% CI = 1.07-1.55). On the contrary, decreased risk for brain tumor (Ala/Val vs. Val/Val: OR = 0.77, 95% CI = 0.68-0.87, dominant model: OR = 0.77, 95% CI = 0.68-0.87 and Ala vs. Val: OR = 0.82, 95% CI = 0.74-0.91). Additionally, we found that the Ala carriers had a significantly increased risk in all models for Asians. Our mRNA expression data provided further biological evidence to consolidate this finding.

CONCLUSIONS

Despite some limitations, this meta-analysis found evidence for an association between the PAPR1 Val762Ala and cancer susceptibility within gastric cancer, brain tumor and Asian subgroups.

The association of the immune response genes to human papillomavirus-related cervical disease in a Brazilian population

The genetic variability of the host contributes to the risk of human papillomavirus (HPV)-related cervical disease. Immune response genes to HPV must be investigated to define patients with the highest risk of developing malignant disease. The aim of this study was to investigate the association of polymorphic immune response genes, namely KIR, HLA class I and II, and single-nucleotide polymorphisms (SNPs) of cytokines with HPV-related cervical disease. We selected 79 non-related, admixed Brazilian women from the state of Paraná, southern region of Brazil, who were infected with high carcinogenic risk HPV and present cervical intraepithelial neoplasia grade 3 (CIN3), and 150 HPV-negative women from the same region matched for ethnicity. KIR genes were genotyped using an in-house PCR-SSP. HLA alleles were typed using a reverse sequence-specific oligonucleotide technique. SNPs of TNF −308G>A, IL6 −174G>C, IFNG +874T>A, TGFB1 +869T>C +915G>C, and IL10 −592C>A −819C>T −1082G>A were evaluated using PCR-SSP. The KIR genes were not associated with HPV, although some pairs of i(inhibitory)KIR-ligands occurred more frequently in patients, supporting a role for NK in detrimental chronic inflammatory and carcinogenesis. Some HLA haplotypes were associated with HPV. The associations of INFG and IL10 SNPs potentially reflect impaired or invalid responses in advanced lesions.

Functional variants in TNFAIP8 associated with cervical cancer susceptibility and clinical outcomes

Tumor necrosis factor-α-induced protein 8 (TNFAIP8) is an anti apoptotic and pro-oncogenic signaling molecule involved in the process of immunity, carcinogenesis and tumor progression. Single nucleotide polymorphisms (SNPs) at microRNA-binding sites may change messenger RNA target gene function, thus leading to cancer susceptibility and tumor progression. In this study of 1584 cervical cancer cases and 1394 cancer-free female controls, we investigated associations between three potentially functional SNPs in TNFAIP8 family genes and cervical cancer risk as well as platinum resistance and clinical outcomes in Eastern Chinese women. We found that the TNFAIP8-rs11064 variant GG genotype was associated with an increased risk of cervical cancer compared with AA/AG genotypes (adjusted odds ratio = 2.16, 95% confidence interval = 1.16-4.03, P = 0.015). Further in vitro and ex vivo functional experiments demonstrated that the TNFAIP8-rs11064 variant G allele weakened the binding affinity of miR-22 to the TNFAIP8 3'-untranslated region (UTR) in four cancer cell lines, resulting in increased production of the TNFAIP8 protein in the patients' cervical tissues. In the survival subset, the high TNFAIP8 protein expression was significantly associated with both resistance to cisplatin and nedaplatin, recurrence and death from cervical cancer. Taken together, in the absence of information on human papillomavirus (HPV) infection, the TNFAIP8-rs11064 SNP may function by affecting the affinity of miR-22 binding to the 3'-UTR of TNFAIP8 and regulating TNFAIP8 expression, thus contributing to cervical cancer risk. Additionally, the increased TNFAIP8 protein expression may predict platinum resistance and clinical outcomes in cervical cancer patients. Larger, prospective studies with detailed HPV infection data are warranted to validate our findings.

A pri-miR-218 variant and risk of cervical carcinoma in Chinese women

BACKGROUND

MicroRNA (miRNA)-related single nucleotide polymorphisms (SNPs) may compromise miRNA binding affinity and modify mRNA expression levels of the target genes, thus leading to cancer susceptibility. However, few studies have investigated roles of miRNA-related SNPs in the etiology of cervical carcinoma.

METHODS

In this case-control study of 1,584 cervical cancer cases and 1,394 cancer-free female controls, we investigated associations between two miR-218-related SNPs involved in the LAMB3-miR-218 pathway and the risk of cervical carcinoma in Eastern Chinese women.

RESULTS

We found that the pri-miR-218 rs11134527 variant GG genotype was significantly associated with a decreased risk of cervical carcinoma compared with AA/AG genotypes (adjusted OR=0.77, 95% CI=0.63-0.95, P=0.015). However, this association was not observed for the miR-218 binding site SNP (rs2566) on LAMB3. Using the multifactor dimensionality reduction analysis, we observed some evidence of interactions of these two SNPs with other risk factors, especially age at primiparity and menopausal status, in the risk of cervical carcinoma.

CONCLUSIONS

The pri-miR-218 rs11134527 SNP was significantly associated with the risk of cervical carcinoma in Eastern Chinese women. Larger, independent studies are warranted to validate our findings.