Association between cytokine gene polymorphisms and cervical cancer in a Chinese population

Vaginal Microbiota and HPV in Latin America: A Narrative Review

With the expansion of human microbiome studies in the last 15 years, we have realized the immense implications of microbes in human health. The human holobiont is now accepted, given the commensal relationships with bacteria, fungi, parasites, viruses, and human cells. The cervicovaginal microbiota is a specific case within the human microbiome where diversity is lower to maintain a chemical barrier of protection against infections. This narrative review focuses on the vaginal microbiome. It summarizes key findings on how native bacteria protect women from disease or predispose them to damaging inflammatory processes with an emphasis on the role of HPV infections in Latin America, one of the world's regions with the highest cervical cancer prevalence.

Small secretory proteins of immune cells can modulate gynecological cancers

Small secretory proteins of immune cells are mostly Cytokines, which include chemokines, interleukins, interferons, lymphokines and tumor necrosis factors but not hormones or growth factors. These secretory proteins are the molecular messengers and primarily involved in autocrine, paracrine and endocrine signaling as immunomodulating agents. Hence, these proteins actually regulate the cells of immune system to communicate with one another to produce a synchronized, robust, still self-regulated response to a specific antigen. Chemokines are smaller secreted proteins that control overall immune cell movement and location; these chemokines are divided into 4 subgroups, namely, CXC, CC, CX3C and C according to the position of 4 conserved cysteine residues. Complete characterization of cytokines and chemokines can exploit their vast signaling networks to develop cancer treatments. These secretory proteins like IL-6, IL-10, IL-12, TNFα, CCL2, CXCL4 & CXCL8 are predominantly expressed in most of the gynecological cancers, which directly stimulate immune effector cells and stromal cells at the tumor site and augment tumor cell recognition by cytotoxic T-cells. Hence; these secretory proteins are the major regulators, which can actually modulate all kinds of gynecological cancers. Furthermore, advancements in adoptive T-cell treatment have relied on the use of multiple cytokines/chemokines to establish a highly regulated environment for anti-tumor T cell growth. A number of in vitro studies as well as animal models and clinical subjects have also shown that cytokines/chemokines have broad antitumor activity, which has been translated into a number of cancer therapy approaches. This review will focus on the foremost cytokines & chemokines involved in the majority of the gynecological malignancies and discuss their basic biology as well as clinical applications.

Genital Cytokines in HIV/Human Papillomavirus Co-Infection: A Systematic Review

Cervical cancer is the fourth cancer in incidence and the third in mortality among women worldwide. Women living with HIV have a significantly increased risk of cervical cancer. The immune response of the host is crucial to determine the course of the human papillomavirus (HPV) infection and cytokines play an important role modulating viral multiplication and concentrating the immune response in the Th1 or Th2 pattern. The aim of this study is to evaluate the available evidence on the concentration of genital cytokines and their role in HPV infection in HIV-infected women. A systematic search of the literature was performed using MEDLINE by PubMed, Embase, Cochrane, LILACS, Scopus, Science direct, and Web of Science databases on November, 2020, in which the following clusters of terms were applied: HIV infection, HPV infection, and cytokine. Initially, 728 articles were selected, but only 17 were eligible for full-text review, and among them, 9 were included in the qualitative analysis. No restriction was applied in language, publication date, or status. The most studied cytokines in the articles included in this review were interferon (IFN)-γ and interleukin (IL)-10 (six articles), tumor necrosis factor (TNF) and IL-6 (five articles), and macrophage inflammatory protein (four articles). The main findings show that there is a reduction in the number of cells expressing IFN-γ (p = .02) and TNF-α (p = .01), in the cervices of HIV-HPV co-infected women compared with those infected only by HPV. In addition, levels of IL-6 (p = .039) and IL-10 (p = .02) are increased in the cervical secretions of HIV-positive women compared to seronegative patients. Despite these findings, there is a clear need of larger studies to understand the role of these immune factors in HPV-induced cervical neoplasia of women co-infected with HIV.

Association of a genetic variant in Interleukin-10 gene with increased risk and inflammation associated with cervical cancer

BACKGROUND

Cervical-cancer is among the most commonly diagnosed cancers in women, and infection with human papillomavirus (HPV) is associated with an increased risk of cervical cancer and altered serum concentrations of inflammatory cytokines. We have explored the association between a genetic variation in the Interleukin-10 (IL-10) gene (rs1800896) and cervical cancer risk and its relationship with tissue Interferon gamma (IFN-γ), Transforming growth factor beta (TGF-β), Tumor necrosis factor alpha (TNF-α) concentrations in women with cervical cancer.

METHODS

A total of 315 women with, or without cervical cancer, were recruited into the study. DNA was extracted from cervical cells, and genotyping was undertaken using Taq-man real-time PCR. The genotype frequency and allele distribution were analyzed together with their association with pathological data. The association of the rs1800896 gene variation with tissue levels of the inflammatory cytokines was also investigated.

RESULTS

Our data showed a significant association between the A allele of the rs1800896 gene variant and the presence of cervical cancer. In particular, patients with AG/AA genotypes had an increased risk of cervical cancer with an odds ratio of 1.929 (95% confidence interval [CI]: 0.879-4.23, P < 0.001) in a recessive model, compared with the GG genotype. Also, the tissue concentrations of IFN-γ, TGF-β, and TNF-α in cervical tissues were significantly higher in women with cervical cancer (P < 0.001) and were associated with the AA genotype.

CONCLUSION

We have found an association between the polymorphism rs1800896 in the IL-10 gene and an increased risk of cervical cancer as well as a higher level of tissue inflammatory cytokines. Further investigations are necessary on the value of emerging biomarkers for the risk stratification for the management of cervical cancer patients.

IL-6 597A/G (rs1800797) and 174G/C (rs1800795) Gene Polymorphisms in the Development of Cervical Cancer in Lithuanian Women

Our study aimed to evaluate the distribution of genotypes and allele frequencies of IL-6 597A/G (rs1800797) and 174G/C (rs1800795) polymorphisms in HPV infected and uninfected healthy women and cervical cancer patients. A PCR based Multiplex HPV genotyping test kit was used for in vitro detection and differentiation of high risk HPV genotypes. Genotyping of two polymorphisms, IL-6 597A/G (rs1800797) and 174G/C (rs1800795), was performed using the KASP genotyping assay kit. Cervical cancer patients were more likely to be HPV positive than control patients. Allele C of IL-6 rs1800795 was associated with a higher risk of cervical cancer by 2.26-fold and genotype CC by 5.37-fold. Genotype CC of IL-6 rs1800795 was more frequent in the HPV positive group compared with the HPV negative group (p = 0.002). Allele G of IL-6 rs1800797 was more frequently found in women with HPV16/HPV18 compared to other HPV types (p = 0.045). Women with AA genotypes of IL-6 rs1800797 were less frequently infected with HPV16/HPV18 compared to other HPV types (p = 0.045). The major finding of the study is the significant association of C allele and CC genotype of IL-6 1800795 gene with cervical cancer in the Lithuanian population. Genotype CC of IL-6 rs1800795 has a significant association with HPV infection as well.

The Impact of Interferon-γ (IFN-γ) and IFN-γ-Inducible Protein 10 (IP-10) Genes' Polymorphism on Risk of Hepatitis C Virus-Related Liver Cirrhosis

Background: Today there is increasing evidence concerning the association between individual genetic polymorphisms within proinflammatory cytokines and chronic hepatitis C (CHC) severity. It has been demonstrated that polymorphisms in some genes may significantly predict HCV infected patients' susceptibility to developing liver cirrhosis or their responsiveness to the treatment.Aim: We investigated the influence of single nucleotide polymorphisms (SNPs) in Interferon (IFN-γ) and Interferon Gamma-Inducible Protein 10 (IP-10) genes on cirrhosis risk in HCV-infected patients and their association with response to various direct-acting antiviral drugs (DAAs).Methods: IFN-γ (+874T/A, +2109A/G) and IP-10 (-135G/A, -1447A/G) genotypes were determined in 175 CHC Egyptian HCV patients (69 liver cirrhotic and 106 non-cirrhotic patients) using either single-stranded polymorphism polymerase chain reaction (SSP-PCR) or Restriction fragment length-PCR (RFLP-PCR) methods.Results: IFN-γ + 874 TA, IP-10 - 135AA, and IP-10 - 1447AA and IP-10 - 1447GG genotypes are increased in patients developing liver cirrhosis compared to non-cirrhotic ones. Although, no statistical significance in their distribution was demonstrated, indicating the lack of association between these SNPs and liver cirrhosis susceptibility in HCV-infected patients. Haplotypes analysis between different loci on all selected genes showed a significant increase in AGGA and TAGA and a significant decrease in TGGA haplotypes in cirrhotic patients. Genotype frequencies at loci -135 and -1447 of IP-10 appeared to be in complete Linkage disequilibrium (LD) (D' = 0.999, r² = 0.689).Conclusion: Our data support the concept that IFN-γ and IP-10 gene polymorphisms are not predictors of disease progression among Egyptian patients with HCV infection.

Role of ganglioside biosynthesis genetic polymorphism in cervical cancer development

Cervical cancer is the most common gynaecological cancer in women. Cell mediated immunity plays a significant role in the progression or regression of neoplastic cervical lesions caused by human papilloma virus infection. Engagement of antigen-specific T cell receptors is a prerequisite for T cell activation. The initial events of T cell activation involve the movement of the T cell receptor into specialised microdomains known as lipid rafts. Gangliosides play an active role in the formation, stabilisation and biological functions of lipid rafts. This study aims to determine whether polymorphisms in the genes involved in the biosynthesis of gangliosides represent risk a factor for cervical cancer.Taqman methods for single nucleotide polymorphism genotyping was used. All subjects carried the homozygous wild-type genotypes for all analysed genes (CC for gene B4GALT5, AA for gene ST3GAL5, AA for gene ST8SIA1 and CC for gene B4GALNT1). A χ2 test showed significant differences in genotype failure for B4GALT5 rs138960078 (χ2 = 32.02, df = 1, p = .001) and genotype failure for B4GALNT1 rs144643461 (χ2 = 41.03, df = 1, p = .001) between cervical cancer group and control group. Genotype failures were significantly more frequent in the cervical cancer group. Unknown adjacent SNPs to rs138960078 in gene B4GALT5 and rs144643461 in gene B4GALNT1 could be associated with cervical cancer development.IMPACT STATEMENTWhat is already known on this subject? Individual genetic factors play an important role in the pathogenesis of disease. In recent years, the different SNPs and their potential effects on CC risk have been extensively studied. A large number of single nucleotide genetic variants associated with cervical cancer have been identified.What do the results of this study add? Our results suggest the presence of unknown adjacent SNPs to rs138960078 in gene B4GALT5 and rs144643461 in gene B4GALNT1 that could be associated with cervical cancer development.What are the implications of these findings for clinical practice and/or further research? Better understanding of causal-consequence relationship between ganglioside biosynthesis and TCR mediated activation with consequently cervical cancer development is needed. Our research opens a new possibilities for identification of polymorphisms in the genes involved in the biosynthesis of gangliosides which can be a risk factor for cervical cancer development.

Broad-Spectrum Preclinical Antitumor Activity of Chrysin: Current Trends and Future Perspectives

Pharmacological profile of phytochemicals has attracted much attention to their use in disease therapy. Since cancer is a major problem for public health with high mortality and morbidity worldwide, experiments have focused on revealing the anti-tumor activity of natural products. Flavonoids comprise a large family of natural products with different categories. Chrysin is a hydroxylated flavonoid belonging to the flavone category. Chrysin has demonstrated great potential in treating different disorders, due to possessing biological and therapeutic activities, such as antioxidant, anti-inflammatory, hepatoprotective, neuroprotective, etc. Over recent years, the anti-tumor activity of chrysin has been investigated, and in the present review, we provide a mechanistic discussion of the inhibitory effect of chrysin on proliferation and invasion of different cancer cells. Molecular pathways, such as Notch1, microRNAs, signal transducer and activator of transcription 3 (STAT3), nuclear factor-kappaB (NF-κB), PI3K/Akt, MAPK, etc., as targets of chrysin are discussed. The efficiency of chrysin in promoting anti-tumor activity of chemotherapeutic agents and suppressing drug resistance is described. Moreover, poor bioavailability, as one of the drawbacks of chrysin, is improved using various nanocarriers, such as micelles, polymeric nanoparticles, etc. This updated review will provide a direction for further studies in evaluating the anti-tumor activity of chrysin.

Association of TNF-a (rs361525 and rs1800629) with susceptibility to cervical intraepithelial lesion and cervical carcinoma in women from Republic of North Macedonia

Cervical cancer (CCa) is one of the most common malign diseases in women associated with human papillomavirus (HPV). The virus is an initiating factor, but not sufficient for the development of cervical intraepithelial lesions (CIN) and CCa. The disease might be a result of the influence of host's genetic factors and polymorphisms in inflammatory-related genes that modify the immune response to HPV and attribute to cancer susceptibility. We carried out a study to determine the association between TNF-a-238G/A and TNF-a-308 G/T polymorphisms with HPV-positive CIN and CCa in women living in the Republic of North Macedonia. Using multiplex SNaPshot analysis for single nucleotide polymorphisms (SNPs), we analysed the genotype and allele distributions of TNF-a-238G/A and TNF-a-308 G/T in 134 cases (HPV-positive and histologically confirmed CIN and CCa) and in 113 controls (cytological and HPV-negative women). For further analysis, the case group was stratified in three subgroups (all cases: CINs+ CCa- group; CIN2+ -group and CIN1- group). Data analysed using the odds ratio (OR) and chi-square test showed the frequency of AA genotypes and A alleles are not significantly higher in cases compared to the controls for both SNPs: AA of TNF-a-238 (0.7% versus 0%) and TNF-a-308 (1.5% versus 0.9%) as well as A allelic frequency (3.0% versus 1.7%) and (13.1% versus 10.6), respectively. The comparison of the case's subgroups with the control group did not show a statistically significant difference. Compared to controls, TNF-a-238G/A and TNF-a-308 G/T are not associated with the risk of HPV associated CIN or CCa in the studied women.

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.

Polymorphisms in IL-1A are associated with endometrial cancer susceptibility among Chinese Han population: A case-control study

Endometrial cancer (EC) is one of the most common malignant tumours of the female genital tract, and it has become a serious malignant disease of the female genital tract in China. Existing researches have revealed the association between polymorphisms of IL-1A and several gynaecological diseases. In this research, we analysed the association between IL-1A gene polymorphisms and endometrial cancer susceptibility in Chinese female population. A total of 81 patients and 198 healthy people were selected. Odds ratio (OR) and 95% confidence intervals (CIs) were calculated using unconditional logistic regression. Genetic models and analyses showed that IL-1A rs3783550 TT and rs3783546 CC increased the risk of endometrial cancer under the recessive model, respectively (rs3783550: OR = 2.80, 95%CI: 1.32-5.92, p = .008; rs3783546: OR = 2.79, 95%CI: 1.32-5.89, p = .008). In the recessive model, we also found that both IL-1A rs1609682 and IL-1A rs3783521 increased the risk of endometrial cancer, respectively (rs1609682: OR = 2.79, 95%CI: 1.32-5.89, p = .0081; rs3783521: OR = 2.80, 95%CI: 1.32-5.92, p = .008). Haplotype analysis was performed that did not reveal any significant results. In summary, IL-1A rs3783550, rs3783546, rs1609682 and rs3783521 polymorphisms may be associated with an increased risk of endometrial cancer in Chinese female populations.

Genetic Susceptibility for Cervical Cancer in African Populations: What Are the Host Genetic Drivers?

Human papillomavirus (HPV) is an essential but not a sufficient cervical cancer etiological factor. Cancer promoters, such as host genetic mutations, significantly modulate therapeutic responses and susceptibility. In cervical cancer, of interest have been viral clearing genes and HPV oncoprotein targets, for which conflicting data have been reported among different populations. This expert analysis evaluates cervical cancer genetic susceptibility biomarkers studied in African populations. Notably, the past decade has seen Africa as a hotbed of biomarker and precision medicine innovations, thus potentially informing worldwide biomarker development strategies. We conducted a critical literature search in PubMed/MEDLINE, Google Scholar, and Scopus databases for case-control studies reporting on cervical cancer genetic polymorphisms among Africans. We found that seven African countries conducted cervical cancer molecular epidemiology studies in one of Casp8, p53, CCR2, FASL, HLA, IL10, TGF-beta, and TNF-alpha genes. This analysis reveals a remarkable gap in cervical cancer molecular epidemiology among Africans, whereas cervical cancer continues to disproportionately have an impact on African populations. Genome-wide association, whole exome- and whole-genome sequencing studies confirmed the contribution of candidate genes in cervical cancer. With such advances and omics technologies, the role of genetic susceptibility biomarkers can be exploited to develop novel interventions to improve current screening, diagnostic and prognostic methods worldwide. Exploring these genetic variations is crucial because African populations are genetically diverse and some variants or their combined effects are yet to be discovered and translated into tangible clinical applications. Thus, translational medicine and flourishing system sciences in Africa warrant further emphasis in the coming decade.

Polymorphisms in the TGFB1 signal peptide influence human papillomavirus infection and development of cervical lesions

The main purpose was to assess the effect of c.29C>T and c.74G>C polymorphisms in the TGFB1 signal peptide on HPV infection and development of cervical lesions. Cervical swabs and blood samples were obtained from 349 outpatient women, along with socio-demographic and sexual behavioral data. The study population was stratified by absence or presence of HPV DNA, as tested by PCR, as well as by lesion grade. TGFB1 signal peptide polymorphisms were genotyped using PCR-restriction fragment length polymorphism. HPV DNA was detected in 172 (49.3%) patients. c.74GC and the combined c.29CC+CT/c.74GC genotype were more frequent in infected patients (35.1 and 15.7%) than in uninfected women (6.2 and 14.7%). Accordingly, these genotypes were associated with a higher risk of HPV infection, with odds ratio and 95% confidence interval of 2.81 and 1.35-5.86 (P = 0.004) for c.74GC and 3.14 and 1.42-6.94 (P = 0.004) for the combined genotype, respectively. High-grade lesions were also 2.48 times more likely to occur in c.29CC patients than in c.29TT patients, with a 95% confidence interval of 1.01-6.08 (P = 0.047). The data demonstrate that c.74G>C and c.29C>T polymorphisms are significantly associated with risk of HPV infection and high-grade squamous intraepithelial lesions, respectively. Thus, TGFB1 signal peptide polymorphisms are potential susceptibility markers.

The correlation between TNF-α-308 gene polymorphism and susceptibility to cervical cancer

Tumor necrosis factor-α (TNF-α) is closely related to the occurrence of human cancers. Cervical cancer seriously affects female health. Therefore, our study aimed to investigate the correlation between the polymorphism of TNF-α-308 gene and susceptibility to cervical cancer. Whole blood was collected from 142 patients with cervical cancer and 150 healthy controls. PCR-RFLP was used to detect the polymorphism of TNF-α-308 and the correlation between polymorphism of TNF-α-308 and the susceptibility to cervical cancer was analyzed. The three genotypes of TNF-α-308 were GG, GA and AA, and the distributions of genotypes of TNF-α-308 were consistent with Hardy-Weinberg equilibrium in both cervical cancer group and control group. There were no significant differences in genotype and allele frequency between cervical cancer group and healthy control group (P>0.05). A/A genotype increased the risk of cervical cancer by 1.46 times with 95% confidence interval of 0.32-6.67. Different genotypes were not associated with tumor type (P>0.05). Different genotypes are correlated with cervical cancer TNM stages, tumor differentiation and lymph node metastasis. Proportion of GA+AA genotype in TNM stage III+IV group, low differentiation group and lymph node metastasis group were 28.1, 29.0 and 29.8%, respectively, which were significantly higher than those in stage I+II group, moderate/high differentiation group and non-lymph node metastasis group (P<0.05). The results suggested that TNF-α-308 gene polymorphism is associated with the degree of malignancy of cervical cancer. Female patients with A allele have higher malignant degree of cervical cancer.

Significant association between interleukin-10 gene polymorphisms and cervical cancer risk: a meta-analysis

Previous studies have suggested that interleukin-10 (IL-10) polymorphisms may be associated with an increased risk of developing cervical cancer. However, the published results on this subject matter are controversial. The aim of this study was to conduct a meta-analysis of published reports to more precisely investigate the relationship between IL-10 polymorphisms and cervical cancer risk. Five online databases (PubMed, Embase, Web of SCI, CNKI and Wanfang) were searched, and seventeen articles with sufficient quantitative information were included in our meta-analysis. The odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the association between IL-10 polymorphisms and cervical cancer risk. Publication bias, sensitivity and cumulative analyses were also performed to support our findings. Overall, there was a significant association between the IL-10 -1082A > G polymorphism and cervical cancer risk observed in the total population (G vs. A: OR = 1.60, 95% CI = 1.12–2.29, P = 0.01, I² = 92.3%; AG vs. AA: OR = 1.34, 95% CI = 1.04-1.74, P = 0.03, I² = 65.9%; AG + GG vs. AA: OR = 1.58, 95% CI = 1.11–2.25, P = 0.01, I² = 84.4%), and the same results were obtained in the subgroup analysis. Moreover, the IL-10 -819 T > C polymorphism exhibited a significant, protective effect against cervical cancer. In summary, our meta-analysis suggests that IL-10 polymorphisms may play a variety of roles in regard to cervical cancer risk, especially in Asians.

Genetic Predisposition to Cervical Cancer and the Association With XRCC1 and TGFB1 Polymorphisms

Objective

Cervical carcinoma (CC), a multifactorial cancer, is assumed to have a host genetic predisposition component that modulates its susceptibility in various populations. We investigated the association between CC risk in Saudi women and 6 single-nucleotide polymorphisms (SNPs) in hypothesis-driven candidate genes.

Methods

A total of 545 females were included, comprising 232 CC patients and 313 age-/sex-matched control subjects. Six SNPs (CDKN1A C31A, ATM G1853A, HDM2 T309G, TGFB1 T10C, XRCC1 G399A, and XRCC3 C241T) were genotyped by direct sequencing.

Results

Of the 6 SNPs studied, TGFB1 T10C (odds ratio, 0.74; 95% confidence interval, 0.57–0.94) and XRCC1 G399A (odds ratio, 1.45; 95% confidence interval, 1.11–1.90) displayed different frequencies in cancer patients and control subjects and showed statistically significant association in univariate (P = 0.017, P = 0.005, respectively) analysis. The Cochran-Armitage trend test had confirmed the results (P = 0.027 and P = 0.006, respectively), indicating an ordering in the effect of the risk alleles in CC patients. The 2 SNPs, TGFB1 T10C and XRCC1 G399A, showed also degrees of deviation from Hardy-Weinberg equilibrium in cancer patients (P = 0.001 and P = 0.083, respectively) but not in the control subjects. Furthermore, correction for multiple testing using multivariate logistic regression to assess the joint effect of all SNPs has sustained significant statistical association (P = 0.025 and P = 0.009, respectively).

Conclusions

TGFB1 T10C and XRCC1 G399A SNPs were associated with CC risk in univariate and multivariate analysis and displayed allele-dosage effects and coselection in cancer patients. Patients harboring the majority allele TGFB1 T10 (Leu) or the variant allele XRCC1 399A (Gln) have approximately 1.5-fold increased risk to develop CC. Host SNPs genotyping may provide relevant biomarkers for CC risk assessment in personalized preventive medicine.

Association of three promoter polymorphisms in interleukin-10 gene with cancer susceptibility in the Chinese population: a meta-analysis

Numerous studies have examined the associations of three promoter polymorphisms (-1082A/G, -819T/C and -592A/C) in IL-10 gene with cancer susceptibility in the Chinese population, but the results remain inconclusive. To gain a more precise estimation of this potential association, we conducted the current meta-analysis based on 53 articles, including 26 studies with 4,901 cases and 6,426 controls for the -1082A/G polymorphism, 33 studies with 6,717 cases and 8,550 controls for the -819T/C polymorphism, and 42 studies with 9,934 cases and 13,169 controls for the -592A/C polymorphism. Pooled results indicated that the three promoter polymorphisms in IL-10 gene were significantly associated with an increased overall cancer risk in the Chinese population. Stratification analysis showed that the association was more pronounced for hepatocellular carcinoma and low quality studies for the -1082A/G polymorphism, lung cancer and oral cancer for the -819T/C polymorphism. However, the -592A/C polymorphism was associated with a statistically significant increased risk for lung cancer, oral cancer, hospital-based studies and low quality studies, but a decreased risk for colorectal cancer. We further investigated the significant results using the false-positive report probability (FPRP) test. Interestingly, FPRP test results revealed that only IL-10 -1082A/G polymorphism was truly associated with an increased overall cancer risk. In the subgroup analysis, only the low quality studies, lung cancer and colorectal cancer remained significant at the prior level of 0.1. Although this association needs further confirmation by considering large studies, this meta-analysis suggested an association between IL-10 gene polymorphisms and cancer risk in the Chinese population.

Note of clarification of data in the paper entitled "Interferon gamma +874 T/A polymorphism increases the risk of cervical cancer: evidence from a meta-analysis"

We read with great interest the paper entitled "Interferon gamma +874 T/A polymorphism increases the risk of cervical cancer: evidence from a meta-analysis" published online by Sun et al. Their results suggest that interferon gamma ( IFNG) gene +874 T/A polymorphism might contribute to women's susceptibility to cervical cancer. They also found that IFNG +874 T/A polymorphism is associated with increased cervical cancer risk in Asian female population. The result is encouraging. Nevertheless, several key issues are worth noticing. We re-evaluate the association between IFNG +874 T/A polymorphism and cervical cancer risk by performing an updated meta-analysis based on 2777 cases and 2542 controls of 11 studies. We found that IFNG +874 T/A polymorphism was not significantly associated with cervical cancer risk in overall population. We also observed that the polymorphism was associated with enhanced cervical cancer risk in Asian population and was relevant to increased squamous cell cervical cancer risk.

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.

Single nucleotide polymorphisms in microRNA genes are associated with cervical cancer susceptibility in a population from Xinjiang Uygur

The goal of this study was to explore the correlation between single nucleotide polymorphisms (SNPs) and susceptibility to cervical cancer (CC) in a population from Xinjiang Uygur. Participating were 247 patients with CC and 285 healthy women. Fourteen SNPs in nine miRNA genes were selected. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using unconditional logistic regression analysis. Multivariate logistic regression analysis was used to assess the correlation of SNPs with CC. The minor allele "C" of rs300574 in SPRY1 was associated with an increased risk of CC based on analysis of the allele, codominant, recessive and log-additive models, but an opposite result was found with the over-dominant model. The minor allele "C" of rs1042725 in HMGA2 was associated with an increased risk of CC in the allele, dominant and log-additive models. In clinical stage III/IVCC patients, rs4728 in SPRY2 was associated with decreased risk. Finally, rs3744935 in BCL2 was associated with CC in the allele and codominant models. In sum, we have detected associations between four SNPs, rs300574 (SPRY1), rs3744935 (BCL2), rs1042725 (HMGA2), and rs4728 (SPRY2), and CC risk in women from Xinjiang Uygur.

Influence of IL-6, IL-8, and TGF-β1 gene polymorphisms on the risk of human papillomavirus-infection in women from Pernambuco, Brazil

Human papillomavirus (HPV) infections are strongly associated with the development of cervical intraepithelial neoplasias and invasive cervical cancer. Polymorphisms in cytokine-encoding genes and behavioural cofactors could play an important role in protecting an individual against viral infections and cancer. Here, we investigated whether IL-6 -174 G>C, IL-8 +396 G>T, and TGF-β1 +869 G>C and +915 G>C polymorphisms were associated with susceptibility to HPV infection in women from north-east (Pernambuco) Brazil. We analysed 108 healthy uninfected women (HC) and 108 HPV-positive women with cervical lesions. Genetic polymorphisms were assessed using Sanger sequencing and polymerase chain reaction-restriction fragment length polymorphism. Comparison of the distribution of the genotypic and allelic frequencies of the IL-18 +396 T>G polymorphism between HPV infected woman an uninfected controls showed that the GG genotype and G allele were both more frequent in the HC group, and were associated with protection from HPV infection (p = 0.0015; OR = 0.29 CI95% = 0.13-0.61; p = 0.0005; OR = 0.45 CI95% 0.29-0.7, respectively). Individuals from the control group could have previously had HPV infection that was spontaneously eliminated; however, it was undetectable at the time of sample collection. Based on our findings, we hypothesize that the IL-8 +396 G>T polymorphism could interfere with susceptibility to HPV infection, by modulating the ability of immune system to fight the virus.

Transforming growth factor-β1 in carcinogenesis, progression, and therapy in cervical cancer

Transforming growth factor β1 (TGF-β1) is a multifunctional cytokine that plays important roles in cervical tumor formation, invasion, progression, and metastasis. TGF-β1 functions as a tumor inhibitor in precancerous lesions and early stage cancers of cervix whereas as a tumor promoter in later stage. This switch from a tumor inhibitor to a tumor promoter might be due to various alterations in TGF-β signaling pathway, such as mutations or loss of expression of TGF-β receptors and SMAD proteins. Additionally, the oncoproteins of human papillomaviruses have been shown to stimulate TGF-β1 expression, which in turn suppresses host immune surveillance. Thus, in addition to driving tumor cell migration and metastasis, TGF-β1 is believed to play a key role in promoting human papillomavirus infection by weakening host immune defense. In this article, we will discuss the role of TGF-β1 in the expression, carcinogenesis, progression, and therapy in cervical cancers. A better understanding of this cytokine in cervical carcinogenesis is essential for critical evaluation of this cytokine as a potential prognostic marker and therapeutic target.

Circulating interleukin-10 levels and human papilloma virus and Epstein-Barr virus-associated cancers: evidence from a Mendelian randomization meta-analysis based on 11,170 subjects

Recent studies have showed interleukin 10 (IL-10) is a critical cytokine that determines antiviral immune response and is related to virus-associated cancers. However, whether genetically elevated circulating IL-10 levels are associated with the risk of human papilloma virus and Epstein–Barr virus-associated cancers (HEACs) is still unclear. Mendelian randomization method was implemented to meta-analyze available observational studies by employing IL-10 three variants (−592C>A, −819C>T, and −1082A>G) as instruments. A total of 24 articles encompassing 11,170 subjects were ultimately eligible for the meta-analysis. Overall, there was a significant association between IL-10 promoter variant −1082A>G and HEACs under allelic and dominant models (both P<0.01). Subgroup analysis by cancer type indicated that the risk estimate of −1082A>G was significant for nasopharyngeal cancer under allelic, homozygous genotypic and dominant models (all P<0.001). Moreover by ethnicity, carriers of −1082G allele had a 74% increased risk for nasopharyngeal cancer in Asians under dominant model (odds ratio [OR] =1.737; 95% confidence interval [CI]: 1.280–2.358; P<0.001). In further Mendelian randomization analysis, the predicted OR for 10 pg/mL increment in IL-10 levels was 1.14 (95% CI: 1.01–16.99) in HEACs. Our findings provided strong evidence for a critical role of genetically elevated circulating IL-10 levels in the development of HEACs, especially in Asian population and for nasopharyngeal cancer.

Association of single nucleotide polymorphisms in tumor necrosis factor-alpha with cervical cancer susceptibility

Tumor necrosis factor-alpha (TNF-α) polymorphisms have been reported to play an important role in the development of cervical cancer. But the results remain inconclusive. We performed this study to provide a comprehensive assessment of the association by means of a meta-analysis in which all published studies were included. The studies investigating the associations between cervical cancer risk and TNF-α polymorphisms were identified through PubMed, Embase, CNKI, and Chinese BioMedical Literature Database. OR and 95% CI (odds ratio and 95% confidence interval) were calculated using either the fixed or random effects model to assess the associations. We eventually included eighteen case-control studies of SNP -308 G>A and nine studies of SNP -238 G>A. Meta-analysis of the former polymorphism suggested significantly increased risk of cervical cancer associated with the A allele (OR 1.19, 95% CI 1.02-1.38). Subgroup analysis according to ethnicity showed similar results in Caucasians (A vs. G: OR 1.25, 95% CI 1.02-1.54; AA vs. GG: OR 1.47, 95% CI 1.04-2.08; AA vs. GA+GG: OR 1.47, 95% CI 1.04-2.08). For SNP -238 G>A, a protective association was observed in overall comparisons (A vs. G: OR 0.64, 95% CI 0.51-0.80; AA+GA vs. GG: OR 0.62, 95% CI 0.49-0.79) and subgroup analysis of Caucasians (A vs. G: OR 0.67, 95% CI 0.53-0.83; AA+GA vs. GG: OR 0.65, 95% CI 0.51-0.82). Our meta-analysis indicates that TNF-α polymorphisms may confer susceptibility to cervical cancer in an ethic-specific fashion.

Distribution of allelic and genotypic frequencies of IL1A, IL4, NFKB1 and PAR1 variants in Native American, African, European and Brazilian populations

BACKGROUND

The inflammatory response plays a key role at different stages of cancer development. Allelic variants of the interleukin 1A (IL1A), interleukin 4 (IL4), nuclear factor kappa B1 (NFKB1) and protease-activated receptor 1 (PAR1) genes may influence not only the inflammatory response but also susceptibility to cancer development. Among major ethnic or continental groups, these polymorphic variants present different allelic frequencies. In admixed populations, such as the Brazilian population, data on distribution of these polymorphisms are limited. Here, we collected samples of cancer-free individuals from the north, northeast, midwest, south and southeast regions of Brazil and from the three main groups that gave rise to the Brazilian population: Native Americans from the Brazilian Amazon, Africans and Europeans. We describe the allelic distributions of four IL1A (rs3783553), IL4 (rs79071878), NFKB1 (rs28362491) and PAR1 (rs11267092) gene polymorphisms, which the literature describes as polymorphisms with a risk of cancer or worse prognosis for cancer.

RESULTS

The genotypic distribution of the four polymorphisms was statistically distinct between Native Americans, Africans and Europeans. For the allelic frequency of these polymorphisms, the Native American population was the most distinct among the three parental populations, and it included the greatest number of alleles with a risk of cancer or worse prognosis for cancer. The PAR1 gene polymorphism allelic distribution was similar among all Brazilian regions. For the other three markers, the northern region population was statistically distinct from other Brazilian region populations.

CONCLUSION

The IL1A, IL4, NFKB1 and PAR1 gene polymorphism allelic distributions are homogeneous among the regional Brazilian populations, except for the northern region, which significantly differs from the other four Brazilian regions. Among the parental populations, the Native American population exhibited a higher incidence of alleles with risk of cancer or worse prognosis for cancer, which can indicate greater susceptibility to this disease. These genetic data may be useful for future studies on the association between these polymorphisms and cancer in the investigated populations.

Climatic droplet keratopathy: an old disease in new clothes

Climatic droplet keratopathy (CDK) is an acquired and potentially handicapping cornea degenerative disease that is highly prevalent in certain rural communities around the world. It predominantly affects males over their forties. It has many other names such as Bietti's band-shaped nodular dystrophy, Labrador keratopathy, spheroidal degeneration, chronic actinic keratopathy, oil droplet degeneration, elastoid degeneration and keratinoid corneal degeneration. CDK is characterized by the haziness and opalescence of the cornea's most anterior layers which go through three stages with increasing severity. Globular deposits of different sizes may be histopathologically observed under the corneal epithelium by means of light and electron microscopy. The coalescence and increased volume of these spherules may cause the disruption of Bowman's membrane and the elevation and thinning of the corneal epithelium. The exact aetiology and pathogenesis of CDK are unknown, but they are possibly multifactorial. The only treatment in CDK advanced cases is a corneal transplantation, which in different impoverished regions of the world is not an available option. Many years ago, the clinical and histological aspects of this disease were described in several articles. This review highlights new scientific evidence of the expanding knowledge on CDK's pathogenesis which will open the prospect for new therapeutic interventions.

Association Study of Single-Nucleotide Polymorphisms of STAT2/STAT3/IFN-γ Genes in Cervical Cancer in Southern Chinese Han Women

OBJECTIVE

Interferon-γ (IFN-γ) and signal transducers and activators of transcription (STATs) each play an important role in carcinogenesis associated with viral infection. Cervical cancer is almost invariably associated with infection by human papillomavirus (HPV), and previous studies suggested that dysregulation of the signal pathway involved in IFN-γ and STATs is associated. Our objective was to evaluate the association of SNPs in STAT2, STAT3, and IFN-γ with cervical cancer susceptibility in Chinese Han women in Hunan province.

MATERIALS AND METHODS

Genomic DNA was extracted from peripheral blood samples of 234 cervical cancer patients and 216 healthy female controls. STAT2 and STAT3 genotyping was performed using polymerase chain reaction-restriction enzyme (PCR-RE) analysis. IFN-γ genotyping was detected by PCR-amplification of specific allele (PASA).

RESULTS

For STAT2 rs2066807 polymorphisms, there was no significant difference of genotype distribution (P=0.827) and allele frequencies (P=0.830, OR=1.09, 95% CI: 0.51-2.31) between cases and controls. For STAT3 rs957970 polymorphisms, there was no significant difference of genotype distribution (P=0.455) and allele frequencies (P=0.560, OR=0.92, 95% CI: 0.71-1.20) between cases and controls. For IFN-γ +874A/T polymorphisms, there was no significant difference of genotype distribution (P=0.652) and allele frequencies (P=0.527, OR=1.12, 95% CI: 0.79-1.59) between cases and controls.

CONCLUSION

These results suggest that polymorphisms in STAT2, STAT3 and IFN-γ genes are not likely to be strong predictors of cervical cancer in Han women in southern China.

Interferon gamma +874 T/A polymorphism increases the risk of cervical cancer: evidence from a meta-analysis

Data from previous studies about the association between interferon gamma (IFN-γ) +874 T/A (rs2430561) polymorphism and cervical cancer risk offer controversial results. To obtain a more dependable conclusion, this meta-analysis was performed. We selected eight articles including nine case-control studies with 1,116 cases and 1,290 controls, odds ratios (OR) with 95 % confidence intervals (CI) were used to assess the strength of the association. Subgroup analysis was carried out by ethnicity, source of controls, genotyping methods, and score of quality assessment. Our meta-analysis indicated that the IFN-γ (+874 T/A) polymorphism significantly increased the risk of cervical cancer in the codominant model (TA vs. TT: OR = 1.471, 95 % CI = 1.137-1.903, P = 0.003, I (2) % = 0.0, P Q  = 0.785) and the dominant model (TA + AA vs. TT: OR = 1.399, 95 % CI = 1.097-1.784, P = 0.007, I (2) % = 0.0, P Q  = 0.486) in the overall population. Stratified analysis by ethnicity indicated a significantly increased risk of cervical cancer in Asians in the codominant model (TA vs. TT: OR = 1.494, 95 % CI = 1.069-2.087, P = 0.019, I (2) % = 0.0, P Q  = 0.440) and the dominant model (OR = 1.455, 95 % CI = 1.062-1.993, P = 0.019, I (2) % = 42.9, P Q  = 0.154). Thus, the IFN-γ (+874 T/A) polymorphism is likely to increase the risk of cervical cancer. Because of the limited studies and sample sizes included in our meta-analysis, further well-designed and large-scale studies are demanded to confirm our results.

Association of IL-10 GTC haplotype with serum level and HPV infection in the development of cervical carcinoma

AIM

Cervical cancer is the most common gynecological malignancy in the developing countries like India. In addition to human papillomavirus (HPV) infection, host genetic factors play an important role in viral persistence and neoplastic growth. IL-10, a multifunctional cytokine, plays an active role to promote tumor growth in the presence of HPV. The present study aims to find out the impact of IL-10 promoter polymorphisms at -1082A/G (rs1800896), -819C/T (rs1800872), and -592C/A (rs1800871) sites along with IL-10 production and HPV infection in the progression of cervical cancer.

METHODS

We have genotyped a total of 506 subjects, 256 cases (208 cervical cancer + 48 precancer), and 250 healthy controls by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method followed by sequencing. IL-10 serum concentration was measured by enzyme-linked immunosorbent assay.

RESULTS

The frequency of IL-10 -592 variant genotype (AA) was found significantly reduced in cases as compare to controls while -1082 variant genotype (GG) was found ~4-fold higher risk of cervical cancer (p = <0.0001, OR = 3.667, 95% CI = 2.329-5.773). On construction of haplotypes, GTC haplotype was emerged as a major risk haplotype while ACA haplotype was seemed as a marker for precancerous lesions. IL-10 serum concentration was observed higher in HPV-infected precancer and cancer cases. GTC haplotype was found to be coupled with higher serum concentration of IL-10 and HPV infection.

CONCLUSION

IL-10 polymorphisms play a role in cervical cancer development and that GTC haplotype, which is closely related to its serum concentration, maybe a useful biomarker for HPV-mediated cervical cancer.

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.

Interleukin-10 gene –1082 G/A polymorphism in cervical cancer and cervical intraepithelial neoplasia: Meta-analysis

Objectives

To assess the association between polymorphism in the interleukin (IL)-10 promoter region of 1082 G/A and the risk of cervical cancer and/or cervical intraepithelial neoplasia (CIN), using meta-analysis.

Methods

The electronic literature databases PubMed®, Embase®, Web of Science, CBMdisc and CNKI were searched for relevant studies. The strength of association between IL-10 gene −1082 G/A polymorphism and cervical cancer and/or CIN was measured using pooled odds ratios with 95% confidence intervals in four genetic models: allelic model (A allele versus G allele); additive model (A/A versus G/G); recessive model (A/A versus G/A+G/G); dominant model (A/A+G/A versus G/G).

Results

Eight studies involving 1983 cases and 1618 controls were identified and included in the meta-analysis. No significant associations were found between IL-10 gene −1082 G/A polymorphism and cervical cancer and/or CIN in any of the genetic models.

Conclusions

IL-10 gene −1082 G/A polymorphism does not appear to be associated with the risk of cervical cancer and/or CIN.

Association of an insertion/deletion polymorphism in IL1A 3'-UTR with risk for cervical carcinoma in Chinese Han Women

Emerging evidence has demonstrated that polymorphisms of interleukin-1 (IL-1) may be involved in human tumorigenesis by regulating the production of this cytokine. Previous studies have investigated the association between two genetic variants (rs3783553 and rs17561) of IL1A and many diseases. The present study was conducted to evaluate whether these two variants are associated with cervical carcinoma (CC). These two polymorphisms were genotyped in 319 CC patients and 424 healthy controls by polymerase chain reaction polyacrylamide gel electrophoresis (PCR-PAGE) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Significantly reduced CC risk was observed to be associated with the insertion allele of rs3783553 (P=0.014, OR=0.71, 95% CI=0.57-0.88). Stratification analysis based on different certain clinical features showed that patients with the heterozygous genotype were associated with a reduced predisposition advancing to clinical stage II-III or developing non-squamous cell carcinoma. Furthermore, patients with the insertion homozygous genotype were also associated with a reduced risk to have a poor tumor differentiation. No significant association was observed between rs17561 and CC. The present study provided evidence that the rs3783553 in IL1A 3'-UTR is inversely associated with CC risk, suggesting an important role IL-1α may play in cervical carcinogenesis.

Lack of association between interferon gamma +874 T/A polymorphism and cancer risk: an updated meta-analysis

Interferon gamma (IFN-γ) is a potent proinflammatory cytokine which plays a pivotal role in the antiviral, antiproliferative, and antitumor activities. A T-to-A transition at the position +874 of human IFN-γ gene (IFNG) has been reported to influence the secretion of IFN-γ and affect cancer susceptibility. However, results from published studies on the association between IFNG +874 T/A polymorphism and cancer risk are inconclusive or even controversial. In order to derive a more precise estimation of the association, a meta-analysis of 38 eligible studies including 5,630 cases and 6,096 controls was conducted with odds ratio (OR) and its corresponding 95 % confidence interval (95 % CI). Overall, no significant association was detected in allelic model (A allele vs. T allele-OR = 0.96, 95 % CI, 0.86-1.08), homozygote comparison (AA vs. TT-OR = 0.97, 95 % CI, 0.79-1.21), heterozygote comparison (AT vs. TT-OR = 1.03, 95 % CI, 0.87-1.23), dominant model (AA + AT vs. TT-OR = 1.00, 95 % CI, 0.87-1.15), nor recessive model (AA vs. AT + TT-OR = 0.93, 95 % CI, 0.78-1.12). Further subgroup analyses based on ethnicity, cancer types, and Hardy-Weinberg equilibrium status failed to demonstrate any significant relationship except in African population under recessive model (AA vs. AT + TT-OR = 0.68, 95 % CI, 0.47-0.97). In conclusion, the current meta-analysis suggested that IFNG +874 T/A polymorphism may not contribute to cancer susceptibility, and further well-designed studies with large sample size are warranted to validate our conclusion.

The role of inflammation in cervical cancer

Knowledge regarding cervical cancer and human papillomavirus is expanding rapidly. Inflammation subsequent to viral infection is a driving force that accelerates cancer development. The infiltrated immune cells and their secretory cytokines along with chemokines and growth factors greatly contribute the malignant traits of cervical cancer. A better understanding of the mechanisms related to inflammation and cancer progression in terms of pathogen survival, cancer development, progression, and metastasis will lead to innovative approach for treating cancer.

Tumor necrosis factor alpha rs1800629 polymorphism and risk of cervical lesions: a meta-analysis

Background

Tumor necrosis factor- alpha (TNF-α) is an inflammatory cytokine which may play important role on the immune response may control the progression of cervical lesions. There is a possible association between TNF-α rs1800629 G/A polymorphism and cervical lesions, but previous studies report conflicting results. We performed a meta-analysis to comprehensively assess the association between TNF-α rs1800629 polymorphism and cervical lesions risk.

Methods

Literature searches of Pubmed, Embase, Web of Science, and Wanfang databases were performed for all publications on the association between TNF-α rs1800629 polymorphism and cervical lesions through December 15, 2012. The pooled odds ratios (ORs) with their 95% confidence interval (95%CIs) were calculated to assess the strength of the association.

Results

Twenty individual case-control studies from 19 publications with a total of 4,146 cases and 4,731 controls were finally included into the meta-analysis. Overall, TNF-α rs1800629 polymorphism was significantly associated with increased risk of cervical lesions under two main genetic comparison models (For A versus G: OR 1.22, 95%CI 1.04–1.44, P = 0.017; for AA versus GG: OR 1.32, 95%CI 1.02–1.71, P = 0.034). Subgroup analysis by ethnicity further showed that there was a significant association between TNF-α rs1800629 polymorphism and increased risk of cervical lesions in Caucasians but not in Asians. Subgroup analysis by the types of cervical lesions showed that there was a significant association between TNF-α rs1800629 polymorphism and increased risk of cervical cancer (For A versus G: OR 1.24, 95%CI 1.05–1.47, P = 0.011; for AA versus GG: OR 1.31, 95%CI 1.01–1.70, P = 0.043; for AA/GA versus GG: OR 1.25, 95%CI 1.01–1.54, P = 0.039).

Conclusion

The meta-analysis suggests that TNF-α rs1800629 polymorphism is associated with increased risk of cervical lesions, especially in Caucasians.

A systemic assessment of the association between tumor necrosis factor alpha 308 G/A polymorphism and risk of cervical cancer

Tumor necrosis factor alpha (TNF-α) is a multifunctional cytokine which plays an important role in the human immune response against various pathogens, and there may be a relationship between TNF-α 308 G/A polymorphism and cervical cancer risk. We performed a meta-analysis to get a systemic assessment of the association between TNF-α 308 G/A polymorphism and cervical cancer risk. Electronic searches of PubMed, Embase, and Web of Science were performed for all publications on the association between TNF-α 308 G/A polymorphism and cervical cancer risk through October 26, 2012. The pooled odds ratios (ORs) with their 95 % confidence interval (95 % CIs) were calculated to assess the association. Fifteen studies with a total of 3,743 cervical cancer cases and 4,096 controls were finally included into the meta-analysis. Overall, TNF-α 308 G/A polymorphism was significantly associated with increased risk of cervical cancer under three main genetic comparison models (A vs. G, OR 1.20, 95 % CI 1.02-1.42, P=0.03; AA vs. GG, OR 1.31, 95 % CI 1.00-1.72, P=0.048; AA vs. GG/GA, OR 1.30, 95 % CI 1.00-1.71, P=0.05). Subgroup analysis by ethnicity further showed that there was a significant association between TNF-α 308 G/A polymorphism and increased risk of cervical cancer in Asians (AA vs. GG, OR 1.83, 95 % CI 1.05-3.20, P=0.034; AA vs. GG/GA, OR 1.84, 95 % CI 1.05-3.22, P=0.032). The meta-analysis suggests that TNF-α 308 G/A polymorphism is associated with increased risk of cervical cancer, and TNF-α 308 G/A mutant allele A is a risk factor of cervical cancer.

Interleukin 10 Polymorphisms and Cervical Cancer Risk: A Meta-Analysis

Background

A debate exists about whether interleukin 10 (IL-10) polymorphisms (IL-10−1082G/A and IL-10−592C/A) confer additional risk for cervical cancer. To derive a more precise estimation of the relationship between IL-10 polymorphisms and cervical cancer risk, we conducted a meta-analysis of all available studies relating the −1082G/A and −592C/A polymorphisms of the IL-10 gene to the risk of developing cervical cancer.

Methods

Eight studies were eligible for IL-10 −1082G/A (1498 cases and 1608 controls), and 5 studies were eligible for IL-10 −592C/A (2396 cases and 1388 controls). Pooled odds ratios (ORs) were appropriately derived from fixed-effects or random-effects models. Subgroup analyses were performed by ethnicity and Hardy-Weinberg equilibrium in the controls.

Results

In the overall analysis, no significant association between the IL-10−1082G/A polymorphism and the risk of cervical cancer was observed. In the subgroup analysis by ethnicity, IL-10 −1082A allele was associated with decreased cervical cancer susceptibility among whites (A vs G: OR, 0.39; 95% confidence interval [CI], 0.32–0.47). Studies with controls deviated from Hardy-Weinberg equilibrium showed an evident association in dominant model (GA/AA vs GG: OR, 1.73 [95% CI, 1.04–2.89]). On the other hand, with respect to −592C/A polymorphism, significantly elevated cervical cancer risk was found in the overall analysis (A vs C: OR, 1.16 [95% CI, 1.04–1.31]; AA vs CC: OR, 1.36 [95% CI, 1.00–1.84]; CA/AA vs CC: OR, 1.18 [95% CI, 1.01–1.39]; AA vs CC/CA: OR, 1.25 [95% CI, 1.01–1.55]). Stratified analysis indicated that significantly increased risks were also found among Asians in the allelic model (A vs C: OR, 1.23 [95% CI, 1.01–1.49]).

Conclusions

Interleukin 10−1082 G/A polymorphism showed no effect on cervical cancer risk in the overall analysis. The genetic polymorphism in IL-10−592C/A is a risk factor for developing cervical cancer, especially for Asians.