IL-8-251A>T polymorphism is associated with breast cancer risk: a meta-analysis

Identification of immune-related mechanisms of cetuximab induced skin toxicity in colorectal cancer patients

Skin rash is a well-known predictive marker of the response to cetuximab (Cmab) in metastatic colorectal cancer (mCRC). However, the mechanism of skin rash development is not well understood. Following exposure to EGFR-targeted therapies, changes in IL-8 levels have been reported. The aim of this study was to evaluate the association between skin rash and inflammatory cytokine levels, including IL-8. Between 2014 and 2017, we prospectively enrolled 38 mCRC patients who underwent chemotherapy with either Cmab or bevacizumab (Bmab) at two hospitals. We performed multiplex cytokine ELISA with 20 inflammatory cytokines including E-selectin, GM-CSF, IFN-alpha, IFN-γ, IL-1 alpha, IL-1 beta, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-17A, IP-10, MCP-1, MIP-1 alpha, MIP-1 beta, P-selectin, sICAM-1, and TNF-alpha at baseline before cycle 1, 24 h after cycle 1, before cycle 2 (= 14 d), and before cycle 3 (= 28 d). Cytokine levels were compared using ANOVA after log-transformation. IL-8 genotypes in 30 patients treated with Cmab were determined using the polymerase chain reaction restriction fragment length polymorphism technique. Depending on the RAS mutational status, 30 and eight patients were treated with Cmab and Bmab-based chemotherapy, respectively. Skin rash developed in 23 (76.6%) of the 30 patients treated with Cmab plus FOLFIRI, after cycle 1. Only the mean log-transformed serum IL-8 level in patients with skin toxicity was statistically lower (2.83 ± 0.15) than in patients who did not experience skin toxicity (3.65 ± 0.27) and received Bmab (3.10 ± 0.26) (ANOVA test, p value = 0.0341). In addition, IL-8 polymorphism did not affect IL-8 levels, skin toxicity, or tumor response in Cmab treated patients. This study suggests that the inflammatory cytokine levels might be affected by Cmab exposure and are associated with the development of skin rash in mCRC patients. Further studies are warranted to evaluate this interaction in Cmab treated patients.

Associations of TLR4 and IL-8 genes polymorphisms with age-related macular degeneration (AMD): a systematic review and meta-analysis

BACKGROUND

The results of different studies have indicated the possible associations of TLR4 and IL-8 genes polymorphisms with Age-related Macular Degeneration (AMD). A meta-analysis study was designed to evaluate the possible associations of TLR4 (rs4986790/c.896A>G and rs4986791/ c.1196 C > T) and IL-8 (rs4073/c.251A>T and rs2227306/c.781 C > T) genes polymorphisms with AMD.

METHOD

A systematic literature search was carried out in PubMed, Embase, Web of Science, and Scopus databases to identify relevant publications. Pooled Odds Ratio (OR) with 95% Confidence Interval (CI) was used to evaluate the power of association.

RESULTS

A total of 12 case-control studies with 4804 AMD patients and 4422 healthy controls were included in this meta-analysis. The analysis of genotypic and allelic models demonstrated significant associations between IL-8 c.781 C > T (CC vs. TT+TC: OR = 0.62 [0.48-0.81], P < .01; CC vs. TC: OR = 0.65 [0.48-0.89], P < .01; TT vs. CC: OR = 1.64 [1.04-2.57], P = .03; and C vs. T: OR = 0.71 [0.65-0.79], P < .01) and risk of AMD, which all of them passed Bonferroni correction for multiple testing (P-value≤0.01), except for TT vs. CC model. In addition, we found associations under the genotypic model of TLR4 c.896A>G (AA vs. AG+GG: OR = 0.73 [0.55-0.97], P = .03; and AA vs. AG: OR = 0.71 [0.53-0.95], P = .02) although after Bonferroni correction (P'-value<0.02) none of these associations remained significant. However, the data from this meta-analysis declined the associations of TLR4 c.1196 C > T and IL-8 c.251A>T polymorphisms with AMD.

CONCLUSION

The current meta-analysis study suggested that IL-8 c.781 C > T polymorphism is associated with susceptibility to AMD.

[Association between interleukin-8 rs4073 polymorphisms and susceptibility to neonatal sepsis]

OBJECTIVE

To study the association between interleukin-8 (IL-8) rs4073 polymorphisms and susceptibility to sepsis in full-term neonates through a prospective study.

METHODS

A total of 50 neonates who were diagnosed with sepsis based on positive blood culture from January to December 2017 were enrolled as the sepsis group. Fifty neonates who had clinical symptoms and negative blood culture were enrolled as the clinical sepsis group. Fifty neonates without infection were enrolled as the control group. Sequencing was used to detect the polymorphisms of IL-8 rs4073. The three groups were compared in terms of the frequencies of genotypes and alleles. A multivariate logistic regression analysis was used to investigate the association of IL-8 rs4073 genotypes with sepsis in full-term neonates.

RESULTS

There were significant differences in the frequencies of genotypes and alleles at IL-8 rs4073 among the three groups (P<0.05). The logistic regression analysis showed that a low gestational age and TT genotype at IL-8 rs4073 were risk factors for the pathogenesis of sepsis in neonates (P<0.05).

CONCLUSIONS

The full-term neonates with TT genotype at IL-8 rs4073 may be susceptible to sepsis.

Association of IL-8 gene promoter -251 A/T and IL-18 gene promoter -137 G/C polymorphisms with head and neck cancer risk: a comprehensive meta-analysis

Purpose

No consensus exists on the impact of polymorphisms in cytokines (such as interleukin IL-8 and IL-18) on cancer risk; moreover, there is very little evidence regarding head and neck cancer (HNC).

Methods

Thus, a meta-analysis including 22 studies with 4731 cases and 8736 controls was conducted to evaluate this association. The summary odds ratio (OR) and corresponding 95% confidence intervals (CIs) for C-X-C motif chemokine ligand 8 (CXCL8, which encodes IL-8) and IL-18 polymorphisms and HNC risk were estimated.

Results

The results showed a significantly increased risk of HNC susceptibility for IL18 −137 G/C in five genetic models, but, interestingly, no significant association was found for the CXCL8 −251 A/T polymorphism. When stratified by cancer type, an increased risk of nasopharyngeal cancer was found for both −137 G/C and −251A/T. When the studies were stratified by ethnicity and genotyping method, there were significant associations between Asian populations and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) studies for −137 G/C, and African populations for −251 A/T in some genetic models. A positive association was also found between the population-based groups in some models for −137 G/C; conversely, significantly decreased risk was found among the −251 A/T hospital-based group. Meta-regression was also conducted. The publication year, control source, and cancer type contributed to CXCL8 −251 A/T heterogeneity; however, no factors were found that contributed to IL-18 −137 G/C heterogeneity. Marginal significance was found in the recessive model for IL-18 −137 G/C by Egger’s test, whereas no publication bias was detected for CXCL8 −251 A/T.

Conclusions

The results indicate that the IL-18 −137 G/C polymorphism is associated with HNC risk, especially nasopharyngeal cancer, in Asian populations and, when using PCR-RFLP, CXCL8 −251 A/T polymorphisms play a complex role in HNC development.

Investigation of association between IL-8 serum levels and IL8 polymorphisms in Chinese patients with sepsis

OBJECTIVE

To assess the clinical relevance of IL8 gene polymorphisms in patients with sepsis and its association with systemic IL-8 levels.

METHODS

PCR and DNA sequencing were used to examine the polymorphism of IL8 in 152 patients with sepsis and in 199 healthy volunteers in China. The distribution frequencies of the genotype and allele were compared among different groups. The serum IL-8 was measured by ELISA and analyzed in relation to polymorphisms of IL8.

RESULTS

The homozygote TT genotype and T allele of rs4073 (genotype: p=0.01, allele: p=0.002), the homozygote CC genotype and C allele (genotype: p=0.03, allele: p=0.003) of rs2227306, homozygote AA genotype and A allele of re1126647 (genotype: p=0.01, allele: p=0.002) were associated with susceptibility to sepsis in males. Serum IL-8 levels were significantly increased in patients with sepsis but showed no correlation with IL8 rs4073, rs2227306 and rs1126647 polymorphisms.

CONCLUSIONS

The male population carrying the homozygote TT genotype and T allele of rs4073, the homozygote CC genotype and C allele of rs2227306 and homozygote AA genotype and A allele of rs1126647 are more susceptible to sepsis, suggesting there is a protective effect in females carrying these genotypes and alleles respectively. There was no association between rs4073, rs2227306 and rs1126647 polymorphisms and serum levels of IL-8 in patients with sepsis.

The CXCL8-CXCR1/2 pathways in cancer

Persistent infection or chronic inflammation contributes significantly to tumourigenesis and tumour progression. C-X-C motif ligand 8 (CXCL8) is a chemokine that acts as an important multifunctional cytokine to modulate tumour proliferation, invasion and migration in an autocrine or paracrine manner. Studies have suggested that CXCL8 and its cognate receptors, C-X-C chemokine receptor 1 (CXCR1) and CX-C chemokine receptor 2 (CXCR2), mediate the initiation and development of various cancers including breast cancer, prostate cancer, lung cancer, colorectal carcinoma and melanoma. CXCL8 also integrates with multiple intracellular signalling pathways to produce coordinated effects. Neovascularisation, which provides a basis for fostering tumour growth and metastasis, is now recognised as a critical function of CXCL8 in the tumour microenvironment. In this review, we summarize the biological functions and ficlinical significance of the CXCL8 signalling axis in cancer. We also propose that CXCL8 may be a potential therapeutic target for cancer treatment

Association between interleukin 8-251 T/A and +781 C/T polymorphisms and glioma risk

Background

Gliomas are aggressive tumors of the central nervous system that rely on production of growth factors for tumor progression. Interleukin 8 (IL-8) is up-regulated in gliomas to promote angiogenesis and proliferation. The aim of this study was to evaluate the association of the IL-8 -251 T/A and +781 C/T polymorphisms and glioma risk.

Methods

We enrolled 300 glioma patients and 300 age- and gender-matched healthy controls. A prospective hospital-based case–control design and logistic regression analysis were utilized. The IL-8 gene polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results

Glioma patients had a significantly higher frequency of IL-8 -251 AA genotype [odds ratio (OR) =1.91, 95 % confidence interval (CI) = 1.22, 3.00; P = 0.005] and IL-8 -251 A allele (OR =1.36, 95 % CI = 1.08, 1.70; P = 0.009) than controls. When stratified by the grade of glioma, patients with WHO IV glioma had a significantly higher frequency of IL-8 -251 AA genotype (OR =1.56, 95 % CI = 1.01, 2.39; P = 0.04).

Conclusions

To the best of our knowledge, this is the first report in the literature that the IL-8 -251 AA genotype and A allele were at a higher risk for glioma.

Association between IL-8 -251A/T and IL-10 -1082A/G genetic polymorphisms and susceptibility to colorectal cancer: A case-control study in a population in Shaanxi

AIM: To explore the association between IL-8 -251A/T and IL-10 -1082A/G polymorphisms and susceptibility to colorectal cancer (CRC) in the population in Shaanxi, China.

METHODS: A case-control study was performed to compare the distribution of genetic frequencies and genotype of IL-8 -251A/T and IL-10 -1082A/G among colorectal cancer patients (n = 102) and control healthy individuals (n = 105) using allele specific PCR (AS-PCR). The relationship between IL-8 -251A/T and IL-10 -1082A/G polymorphisms and susceptibility to colorectal cancer was explored.

RESULTS: There was a significant difference in the distribution of genotype of IL-8 -251A/T between the healthy control group and CRC group (χ² = 8.278, P = 0.016). The genetic frequency of IL-8 -251A allele in CRC was 0.54 (111/204), which was significantly higher than that of the controls (0.43, 91/210) (χ² = 5.083; P = 0.024). The subjects carrying AA genotype were more likely to suffer from CRC (OR = 3.84, 95%CI: 1.44-10.23). Stratified analysis suggested that the association between the AA genotype of IL-8 -251A/T and the risk of CRC was more profound in subjects less than 55 years old and smokers. However, no difference was discovered in the distribution of genotype of IL-10 -1082A/G between the CRC group and healthy control group (χ² = 1.808, P = 0.405).

CONCLUSION: The IL-8 -251AA genotype may be a risk factor of CRC in the population in Shaanxi, and people with A allele may be more likely to suffer from CRC, especially in those less than 55 years old and smokers. No correlation is found between IL-10 -1082A/G polymorphism and the risk of CRC.

Quantitative assessment of the associations between interleukin-8 polymorphisms and periodontitis susceptibility

BACKGROUND

This review assesses the associations of interleukin-8 gene (IL-8) -251A/T (rs4073) and -845T/C (rs2227532) polymorphisms with susceptibility to periodontitis.

METHODS

Several electronic databases were searched for eligible articles. Twelve studies involving 2,233 cases and 2,655 controls were retrieved and analyzed. Odds ratios (ORs) along with 95% confidence intervals (CIs) were calculated to assess the strength of relationship between the IL-8 polymorphisms and periodontitis risk.

RESULTS

No significant association was found for IL-8 -251A/T polymorphism with periodontitis in the overall analysis and stratification by periodontitis type and smoking status. Subgroup analysis by ethnicity revealed that -251A/T T allele and TT genotype were associated with decreased risk of periodontitis in a Brazilian mixed population (T allele versus A allele: OR 0.80, 95% CI 0.68 to 0.94, Pheterogeneity = 0.30; TT versus AA: OR 0.65, 95% CI 0.46 to 0.93, Pheterogeneity = 0.39; TT versus

AA/AT

OR 0.58, 95% CI 0.35 to 0.98, Pheterogeneity = 0.01). In addition, -251A/T T allele was associated with increased periodontitis risk in Asians. Pooled estimates showed that the -845T/C polymorphism was associated with periodontitis susceptibility in overall analysis and the chronic periodontitis subgroup. In addition, marginal associations were observed between -845T/C polymorphism and periodontitis in a Brazilian mixed population. Moreover, this association was also confirmed to be significant in Brazilian non-smokers.

CONCLUSION

This meta-analysis indicated that both IL-8 -251A/T and -845T/C polymorphisms may be involved in the development of periodontitis in a Brazilian mixed population, whereas the -251A/T allele T appeared to be a risk factor for periodontitis in Asians.

Ethnic background and genetic variation in the evaluation of cancer risk: a systematic review

The clinical use of genetic variation in the evaluation of cancer risk is expanding, and thus understanding how determinants of cancer susceptibility identified in one population can be applied to another is of growing importance. However there is considerable debate on the relevance of ethnic background in clinical genetics, reflecting both the significance and complexity of genetic heritage. We address this via a systematic review of reported associations with cancer risk for 82 markers in 68 studies across six different cancer types, comparing association results between ethnic groups and examining linkage disequilibrium between risk alleles and nearby genetic loci. We find that the relevance of ethnic background depends on the question. If asked whether the association of variants with disease risk is conserved across ethnic boundaries, we find that the answer is yes, the majority of markers show insignificant variability in association with cancer risk across ethnic groups. However if the question is whether a significant association between a variant and cancer risk is likely to reproduce, the answer is no, most markers do not validate in an ethnic group other than the discovery cohort's ancestry. This lack of reproducibility is not attributable to studies being inadequately populated due to low allele frequency in other ethnic groups. Instead, differences in local genomic structure between ethnic groups are associated with the strength of association with cancer risk and therefore confound interpretation of the implied physiologic association tracked by the disease allele. This suggest that a biological association for cancer risk alleles may be broadly consistent across ethnic boundaries, but reproduction of a clinical study in another ethnic group is uncommon, in part due to confounding genomic architecture. As clinical studies are increasingly performed globally this has important implications for how cancer risk stratifiers should be studied and employed.

Positive association between Interleukin-8 -251A > T polymorphism and susceptibility to gastric carcinogenesis: a meta-analysis

Backgrounds

The associations between the polymorphisms of interleukin-8 (IL-8) gene and gastric carcinogenesis have been extensively investigated in recent years. However, the results remain conflicting rather than conclusive.

Methods

A meta-analysis of 18 eligible studies was performed to evaluate the association of IL-8 -251A > T polymorphism with risk of gastric carcinogenesis. A systematic literature search of MEDLINE, Embase, and Web of Science, CNKI databases was conducted. Statistical analysis was performed by using the Revman 5.1 software and the Stata 12.0 software.

Results

Of the 293 unique studies identified using our search criteria, 18 studies fulfilled our inclusion criteria and were included in the meta-analysis. These studies cumulatively reported 5,321 cases and 6,465 controls. The combined results based on all studies showed that the IL-8 -251A > T polymorphism was associated with the risk of gastric carciongenesis (A vs. T: OR: 1.14 [1.02, 1.26], P = 0.02), especially gastric cancer (A vs. T: OR: 1.15 [1.03, 1.29], P = 0.02), but not associated with the risk of precancerous lesion (A vs. T: OR: 1.09 [0.99, 1.20], P = 0.08). Analysis stratified by ethnicity may seem that IL-8 -251A > T polymorphism was susceptible to gastric cancer in Asian population, but not in Caucasian population.

Conclusions

Our meta-analysis results provide evidence that IL-8 -251A > T polymorphism is significantly associated with increased risk of gastric carcinogenesis in Asian population, particularly in gastric cancer. Further large and well-designed studies are required to confirm this conclusion.

DNMT3B polymorphisms and cancer risk: a meta analysis of 24 case-control studies

The association between polymorphism of DNA methyltransferases 3B and cancer risk has been widely studied recently, and no consensus conclusion is available up to now. We perform a comprehensive search using the databases of Medline, ISI Web of Knowledge and Embase. The odds ratio (OR) and its 95% confidence interval (95% CI) are used to investigate the strength of the association. A total of 24 case-control studies with 15,647 individuals are included in this meta-analysis. For -149C > T (17 studies, 5229 cases and 6910 controls), no evidence indicate that individuals carrying the variant genotypes (CC + CT), relative to those carrying the wild homozygote TT genotype, have an increased risk of cancer (OR = 1.03; 95% CI = 0.84-1.26; P = 0.76). Similarly, no cancer risk is found in the subgroup analyses. For -579G > T (11 studies, 3513 cases and 3714 controls), significantly decreased risks of cancer are observed, and the ORs (95% CI) are 0.70 (0.56-0.87) for GT versus TT, 0.70 (0.57-0.85) for GG + GT versus TT and 0.76 (0.63-0.93) for G-allele versus T-allele, respectively. Subgroup analyses stratified by ethnicity and types of cancer are also performed, and results indicated that -579G > C polymorphism is associated with risk of cancer in Asians [0.68 (0.53-0.87) for GT vs. TT] but not in Europeans [0.82 (0.63-1.07) for GT vs. TT]. We also observe that the -579G is associated with decreased risk of colorectal cancer [0.49(0.38-0.62) for GT vs. TT]. More studies with larger sample size were needed to provide more precise evidence.