The interleukin-8 (-251A/T) polymorphism is associated with increased risk for oral squamous cell carcinoma

The role of neck adipose tissue in lymph node metastasis of head and neck cancer

Previous studies indicated that adipose tissue significantly influences cancer invasion and lymphatic metastasis. However, the impact of neck adipose tissue (NAT) on lymph node metastasis associated with head and neck cancer remains ambiguous. Here, we systematically assess the classification and measurement criteria of NAT and evaluate the association of adipose tissue and cancer-associated adipocytes with head and neck cancer. We delve into the potential mechanisms by which NAT facilitate cervical lymph node metastasis in head and neck cancer, particularly through the secretion of adipokines such as leptin, adiponectin, and Interleukin-6. Our aim is to elucidate the role of NAT in the progression and metastasis of head and neck cancer, offering new insights into prevention and treatment.

Evaluation of interleukin 8 polymorphisms (-251T/A and +781C/T) in patients with hepatocellular carcinoma: a meta-analysis

Aim of the study

We reported the association between interleukin 8 (IL-8) polymorphisms (-251T/A and +781C/T) and hepatocellular carcinoma (HCC) risk in a meta-analysis.

Material and methods

Scopus, PubMed, Web of Science, and Cochrane Library databases were searched until 21 November 2020. The analyses were performed by RevMan 5.3 software using odds ratios (ORs) and 95% confidence intervals (CIs). Also, the analysis of publication bias was performed by CMA 2.0 software.

Results

Searching databases/sources, five articles including ten studies were entered into the meta-analysis. The pooled ORs for -251T/A polymorphism were 1.07 (p = 0.55), 1.04 (p = 0.75), 1.31 (p = 0.24), 1.24 (p = 0.31), and 1.85 (p = 0.29) for allele, homozygote, heterozygote, recessive and dominant models, respectively. With regards to +781C/T polymorphism, the pooled ORs were 0.74 (p = 0.07), 0.53 (p = 0.03), 0.83 (p = 0.41), 0.75 (p = 0.19), and 0.57 (p = 0.02) for allele, homozygote, heterozygote, recessive, and dominant models, respectively.

Conclusions

The findings of the meta-analysis showed a lack of significant association between IL-8 (-251T/A) polymorphism and the HCC risk, whereas the TT genotype of IL-8 (+781C/T) polymorphism had a protective role in HCC.

Identification of diagnostic and prognostic lncRNA biomarkers in oral squamous carcinoma by integrated analysis and machine learning

BACKGROUND

Patients with oral squamous carcinoma (OSCC) present difficulty in precise diagnosis and poor prognosis.

OBJECTIVE

We aimed to identify the diagnostic and prognostic indicators in OSCC and provide basis for molecular mechanism investigation of OSCC.

METHODS

We collected sequencing data and clinical data from TCGA database and screened the differentially expressed mRNAs (DEmRNAs) and lncRNAs (DElncRNAs) in OSCC. Machine learning and modeling were performed to identify the optimal diagnostic markers. In order to determine lncRNAs with prognostic value, survival analysis was performed through combing the expression profiles with the clinical data. Finally, co-expressed DEmRNAs of lncRNAs were identified by interacted network construction and functional annotated by GO and KEGG analysis.

RESULTS

A total of 1114 (345 up- and 769 down-regulated) DEmRNAs and 156 (86 up- and 70 down-regulated) DElncRNAs were obtained in OSCC. Following the machine learning and modeling, 15 lncRNAs were identified to be the optimal diagnostic indicators of OSCC. Among them, FOXD2.AS1 was significantly associated with survival rate of patients with OSCC. In addition, Focal adhesion and ECM-receptor interaction pathways were found to be involved in OSCC.

CONCLUSIONS

FOXD2.AS1 might be a prognostic marker for OSCC and our study may provide more information to the further study in OSCC.

Association study indicates combined effect of interleukin-10 and angiotensin-converting enzyme in basal cell carcinoma development

Cytokines involved in inflammatory and immune response have been associated with risk for development of basal cell carcinoma (BCC). In this study, three functional DNA polymorphisms affecting gene expression were investigated in 54 BCC patients and 111 healthy controls: interleukin-1b (IL-1b) +3953C/T, interleukin-10 (IL-10) - 1082G/A and angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphisms. Significant increase of the variant alleles was observed in IL-10 - 1082G (P = 0.019) and in ACE D (P = 0.003) in BCC patients in comparison to controls. Multivariate logistic regression models evaluated the contribution of homozygous and heterozygous variant polymorphisms to the risk for BCC development. The studied polymorphisms influencing the expression of IL-10 and ACE genes were recognized as potential predictive factors for BCC. These findings suggest a possible molecular mechanism leading to BCC development that is likely to involve the activation of angiotensin receptors in combination with increased plasma levels of IL-10 in patients.

Association between the Interleukin-10 -1082 G/A polymorphism and risk of hepatocellular carcinoma

BACKGROUND

Inconsistent results have been reported from studies investigating the relationship of the interleukin-10 (IL-10) -1082 G/A polymorphism and the susceptibility of hepatocellular carcinoma (HCC). Therefore, a thorough literature review of relatedstudies was performed in this meta-analysis to examine the association of the interleukin-10(IL-10) -1082 G/A polymorphism with HCC susceptibility.

METHODS

Electronic databases were searched for literature on the relationship between interleukin-10(IL-10) -1082 G/A polymorphism and the risk of HCC in accordance with the inclusion and exclusion criteria. The selected studies were analyzed using the Stata 12.0 software. Finally, the strength of the associations was evaluated using the odds ratio (OR) and 95% confidence intervals (95% CI).

RESULTS

A total of six case-control studies were enrolled into the current meta-analysis, which included a total of 911 patients and 1889 control subjects. Our data revealed no association between the IL-10 -1082 G/A polymorphism and the risk of HCC (GG vs AA:OR=0.84, 95%CI=0.57-1.25; AG vs AA:OR=0.85, 95%CI=0.70-1.05; Dominant model: OR=0.85, 95%CI=0.70-1.03; and Recessive model: OR=0.92, 95%CI = 0.64-1.32). Similarly, no association was found in sub-group analysis based on ethnicity.

CONCLUSION

The results of our study suggest no association between IL-10 -1082 G/A polymorphism and the risk of HCC.

Association of polymorphisms in IL-8, MMP-1 and MMP-13 with the risk and prognosis of oral and oropharyngeal squamous cell carcinoma

OBJECTIVE

This study investigated the risk and prognostic value of single nucleotide polymorphisms (SNP) inIL-8, MMP-1 and MMP-13 in oral and oropharyngeal squamous cell carcinomas (SCCs).

DESIGN

SNPs rs2227532 and rs4073 inIL-8, rs2071230 and rs470558 in MMP-1, and rs2252070 in MMP-13 were genotyped in 125 oral and oropharyngeal SCC patients and 130 healthy controls, using TaqMan allelic discrimination assays. Multiple logistic regression models were used to explore the association between SNPs and cancer development, as well as SNP-SNP interaction and gene-environmental factor (GxE) interaction. Univariate and multivariate methods were applied for survival analyses.

RESULTS

With exception of rs2227532, all the SNPs were in Hardy-Weinberg equilibrium in the control. No associations between rs4073 in IL-8 and rs2071230 and rs470558 in MMP-1 were observed, but rs2252070 in MMP-13, in the dominant model, was associated in a protective manner to oral and oropharyngeal SCC (OR: 0.20, 95% CI: 0.06-0.71, p = 0.007). All SNPs interact significantly with cigarette smoking and alcohol consumption on susceptibility to oral and oropharyngeal SCC, but they showed no influence on survival of the patients.

CONCLUSIONS

Our results show that rs2252070 inMMP-13 may confer protection effect against oral and oropharyngeal SCC. In addition, the combined effects of IL-8 (rs4073), MMP-1 (rs2071230 and rs470558) and MMP-13 (rs2252070) with environmental carcinogens, such as tobacco and alcohol, are related to increased risk for oral and oropharyngeal SCC development.

Role of polymorphisms in genes that encode cytokines and Helicobacter pylori virulence factors in gastric carcinogenesis

The Helicobacter pylori (H. pylori) infection is a determinant factor in gastric cancer (GC) development. However, the infection outcomes are variable and depend on both host and bacterial characteristics. Some host cytokines such as interleukin (IL)-1β, IL-1Ra, IL-8, IL-10 and tumor necrosis factor-α play important roles in the host immune system response to the pathogen, in the development of gastric mucosal lesions and in cell malignant transformation. Therefore, these host factors are crucial in neoplastic processes. Certain polymorphisms in genes that encode these cytokines have been associated with an increased risk of GC. On the other hand, various virulence factors found in distinct H. pylori bacterial strains, including cytotoxin-associated antigen A, vacuolating cytotoxin, duodenal ulcer promoting gene A protein, outer inflammatory protein and blood group antigen binding adhesin, have been associated with the pathogenesis of different gastric diseases. The virulent factors mentioned above allow the successful infection by the bacterium and play crucial roles in gastric mucosa lesions, including malignant transformation. Moreover, the role of host polymorphisms and bacterial virulence factors in gastric carcinogenesis seems to vary among different countries and populations. The identification of host and bacterium factors that are associated with an increased risk of GC development may be useful in determining the prognosis of infection in patients, what could help in clinical decision-making and in providing of an optimized clinical approach.

Polymorphisms of TNF-α -308 G/A and IL-8 -251 T/A Genes Associated with Urothelial Carcinoma: A Case-Control Study

Cigarette smoking and exposure to environmental tobacco smoke are well-known risk factors for urothelial carcinoma (UC). We conducted a hospital-based case-control study involving 287 UC cases and 574 cancer-free controls to investigate the joint effects of cigarette smoking and polymorphisms of inflammatory genes on UC risk. Tumor necrosis factor alpha (TNF-α) -308 G/A and interleukin-8 (IL-8) -251 T/A polymorphisms were determined using a polymerase chain reaction-restriction fragment length polymorphism method. People who had ever smoked and those who were exposed to environmental tobacco smoke had significantly increased UC odds ratios (ORs) of 1.65 and 1.68, respectively. Participants who had smoked more than 18 pack-years had a significantly increased UC OR of 2.64. People who had ever smoked and who carried the A/A genotype of the TNF-α -308 G/A polymorphism had a significantly higher UC OR (10.25) compared to people who had never smoked and who carried the G/G or G/A genotype. In addition, people who had ever smoked and who carried the IL-8 -251 T/T genotype had a significantly increased UC OR (3.08) compared to people who had never smoked and who carried the T/A or A/A genotype. In a combined analysis of three major risk factors (cumulative cigarette smoking, the TNF-α -308 A/A genotype, and the IL-8 -251 T/T genotype), subjects with any one, any two, and all three risk factors experienced significantly increased UC ORs of 1.55, 2.89, and 3.77, respectively, compared to individuals with none of the risk factors. Conclusions. Our results indicate that the combined effects of cumulative cigarette exposure and the TNF-α -308 A/A genotype and/or the IL-8 -251 T/T genotype on UC OR showed a significant dose-response relationship.

Association between polymorphisms in selected inflammatory response genes and the risk of prostate cancer

Inflammation represents an important event which facilitates prostate carcinogenesis. Genetic variations in inflammatory response genes could affect the level and function of the protein products, resulting in the differential prostate cancer risk among carriers of different variants. This study attempted to investigate the association of IL-4 rs2243250, IL-6 rs10499563, IL-8 rs4073, as well as NFKBIA rs2233406 and rs3138053 polymorphisms with prostate cancer risk in the Chinese population. Genotyping of the polymorphisms was performed by using polymerase chain reaction-restriction fragment length polymorphism technique on 439 prostate cancer patients and 524 controls, and the association of each polymorphic genotype with prostate cancer risk was evaluated by using logistic regression analysis based on allele, heterozygous, and homozygous comparison models, with adjustment to age and smoking status. We showed that the C allele of IL-4 rs2243250 polymorphism could increase prostate cancer risk (heterozygous comparison model: odds ratio [OR] =1.434, 95% confidence interval [CI] =1.092–1.881, P=0.009; homozygous comparison model: OR =2.301, 95% CI =1.402–3.775, P=0.001; allele comparison model: OR =1.509, 95% CI =1.228–1.853, P<0.001). On the other hand, the C allele of rs10499563 polymorphism could decrease prostate cancer risk (heterozygous comparison model: OR =0.694, 95% CI =0.525–0.918, P=0.010; homozygous comparison model: OR =0.499, 95% CI =0.269–0.926, P=0.028; allele comparison model: OR =0.692, 95% CI =0.553–0.867, P=0.001). No association was observed for the other polymorphisms. In conclusion, IL-4 rs2243250 and IL-6 rs10499563 polymorphisms could serve as potential predictive biomarkers for prostate cancer risk in the Chinese population.

IL-8 and VEGFR-2 polymorphisms modulate long-term functional response to intravitreal ranibizumab in exudative age-related macular degeneration

AIM

To investigate possible associations between VEGFR-2 and IL-8 gene SNPs and 1-year response to intravitreal ranibizumab for exudative age-related macular degeneration.

MATERIALS & METHODS

Sixty-four eyes underwent a loading phase of three monthly intravitreal injections of ranibizumab 0.5 mg/0.05 ml followed by Pro Re Nata retreatment. VEGFR-2 rs2071559 (-604 A/G) and IL-8 rs4073 (-251 A/T) were analyzed.

RESULTS

Ranibizumab was significantly more effective as measured by visual acuity in patients harboring the IL-8 rs4073 TT genotype (p = 0.045), whereas patients carrying the VEGFR-2 rs2071559 CC genotype revealed better functional response as measured by mean retinal sensitivity (p = 0.034).

CONCLUSION

IL-8 rs4073 and VEGFR-2 rs2071559 genotypes may represent important molecular determinants to modulate final outcomes in neovascular age-related macular degeneration patients.

Association between interleukin 8 -251 A/T and +781 C/T polymorphisms and osteosarcoma risk in Chinese population: a case-control study

Interleukin-8 (IL-8) is an angiogenic chemokine that plays a potent role in both development and progression of many human malignancies. However, there are no data about the role of IL-8 polymorphism in development of osteosarcoma. A hospital-based case-control study was conducted among 190 patients with osteosarcoma and 190 healthy controls to investigate the possible association between the IL-8 -251 A/T and +781 C/T polymorphisms, respectively, and the risk of osteosarcoma. Significant differences of genotype distribution were observed between osteosarcoma cases and controls at the IL-8 -251T/A genotypes. Compared with the IL-8 -251T/A homozygote TT, the heterozygous TA genotype was associated with significantly increased risk for osteosarcoma (odds ratio (OR) = 2.16, 95 % confidence interval (CI) = (1.38-4.52), P = 0.021); the AA genotype was associated with increased risk for osteosarcoma (OR = 1.94, 95 % CI = 1.31-3.83, P = 0.018). TA and AA combined variants were associated with increased risk for osteosarcoma compared with the TT genotype (OR = 1.72, 95 % CI = 1.45-4.41, P = 0.023). Moreover, the genotype AA of IL-8 -251T/A carried a higher risk of osteosarcoma metastasis and later Enneking stages, compared with the TT genotype. However, the genotype and allele frequencies of IL-8 +781 C/T polymorphisms in osteosarcoma patients were not significantly different from controls. Our results showed that the IL-8 -251 A/T genotype was associated with increased risk for development and metastasis of osteosarcoma in Chinese Han population.

Interleukin 10 gene -1082A/G polymorphism is associated with osteosarcoma risk and poor outcomes in the Chinese population

Interleukin-10 (IL-10) is a multifunctional cytokine that participates in the development and progression of various malignant tumors. However, data regarding the role of IL-10 polymorphisms in osteosarcoma development are not available. A case-control study was conducted in 260 patients with osteosarcoma and 260 healthy controls to investigate the possible association between IL-10 polymorphisms and the risk of osteosarcoma. Our results indicate the IL-10 -1082A/G (rs1800896) polymorphism is significantly associated with an increased risk of osteosarcoma in all genetic models (AG vs. AA, odds ratio (OR) = 1.56; 95 % confidence interval (CI) = 1.28-2.32, P = 0.017; GG vs. AA, OR = 1.62, 95 % CI 1.24-2.61, P = 0.013; AG + GG vs. CC, OR = 1.76, 95 % CI = 1.31-3.01, P = 0.019). However, the genotype and allele frequencies of IL-10 -819C/T (rs1800871) and -592A/C (rs1800872) polymorphisms in osteosarcoma patients did not significantly differ from controls. Further analyses revealed that the IL-10 -1082A/G (rs1800896) genotypes were associated with advanced tumor stages and metastasis in osteosarcoma patients. Additionally, a statistically significant association between the IL-10 -1082A/G (rs1800896) genotype and poor survival in osteosarcoma patients was observed. Our results demonstrate that the IL-10 -1082A/G (rs1800896) genotype is associated with an increased susceptibility and worse outcome for osteosarcoma patients in the Chinese Han population.

Potential role of differentially expressed lncRNAs in the pathogenesis of oral squamous cell carcinoma

Long non-coding RNAs (lncRNAs) have recently attracted more attention about the role in a broad range of biological processes and complex cancers. We aimed to identify differentially expressed lncRNAs that play an important role in the pathogenesis of oral squamous cell carcinoma (OSCC). Microarray data GSE25099 consisting of 57 samples from patients with OSCC and 22 normal samples were downloaded from Gene Expression Omnibus database. Differentially expressed genes (DEGs) and lncRNAs were identified between OSCC samples and control using samr package in R and noncoder software. Co-expression network was constructed for lncRNAs and candidate target DEGs, followed by functional and pathway enrichment analysis using the Database for Annotation, Visualization and Integrated Discovery online tool. OSCC-related genes were screened by Genetic-Association-DB-Database analysis, and then protein-protein interaction (PPI) network construction of OSCC-related and co-expressed genes. Bioinformatic analysis revealed that there were 998 DEGs and 160 differentially expressed lncRNAs between OSCC and normal control. We found LOC100130547, FTH1P3, PDIA3F and GTF2IRD2P1 targeted most of DEGs. Predicted targets-related functional annotation showed significant changes in inflammation-related functions and Toll-like receptor signaling pathway. By further conducting PPI network with lncRNA co-expressed DEGs, we found that OSCC-associated genes including MMP1 (matrix metallopeptidase), MMP3, MMP9, PLAU (plasminogen activator, urokinase) and IL8 (interleukin 8) were targeted by FTH1P3, PDIA3F and GTF2IRD2P1. Our results indicate that lncRNAs FTH1P3, PDIA3F and GTF2IRD2P1 may responsible for progression and metastasis of OSCC via targeting MMP1, MMP3, MMP9, PLAU and IL8 which are key regulators of tumorigenesis.

The role of interleukin-6 and interleukin-8 gene polymorphisms in non-alcoholic steatohepatitis

BACKGROUND

Genetic polymorphisms may play role in the pathophysiology of nonalcoholic steatohepatitis (NASH).

OBJECTIVES

We purposed to assess the role of interleukin 6 (IL 6) and interleukin 8 (IL 8) gene polymorphisms in the pathogenesis of NASH.

PATIENTS AND METHODS

Consecutive patients with biopsy proven NASH and age- and gender-matched healthy individuals with normal liver function tests and normal ultrasonography were enrolled in the study. Histopathological findings were recorded according to nonalcoholic fatty liver disease activity score (NAS). Patients were classified according to fibrosis scores as fibrosis score < 2 (mild fibrosis group) and fibrosis score ≥ 2 (significant fibrosis group). Blood samples were collected and genomic DNA isolation kit was used to evaluate genetic polymorphisms.

RESULTS

Of thirty-eight patients, 27 (71%) were in mild fibrosis group and 11 (29%) in significant fibrosis group. Thirty-eight age- and gender-matched healthy controls were enrolled in the study. The frequencies of genotypes G/C and G/G of IL 6 among the NASH group and healthy controls were 39.5% and 60.5% vs. 53.6% and 46.4%, respectively (P = 0.32). The frequencies of the genotypes of IL 8 among the NASH group were 47.2%, 44.6%, and 8.2% for T/T, A/T, and A/A, and in healthy controls were 50%, 28.6% and 21.4%, respectively, (P = 0.568). The differences between IL 8 gene T/A and T/T genotypes were not significant statistically (P > 0.05). However, the frequency of A/A genotype in significant fibrosis group was higher than the mild fibrosis group (P = 0.0016). The differences of -251 A/T polymorphism in the IL 8 and -174 C/G polymorphism in the IL 6 were not statistically significant between fibrosis groups (P > 0.05).

CONCLUSIONS

IL6 and IL8 gene polymorphisms have no role in NASH pathogenesis and liver fibrosis process, but presence of the A/A genotype in the IL8 gene is associated with disease progression.

Association of IL-8-251A>T polymorphisms with oral cancer risk: evidences from a meta-analysis

The findings of associations between interleukin-8 (IL-8) polymorphisms and risk of oral cancer are controversial. We conducted a meta-analysis on the basis of data from all published studies to provide evidence of the current understanding of the genetic association with oral cancer. Eligible studies were identified by means of an electronic search of PubMed, Elsevier, ScienceDirect, EMBASE, EBSCO, and CBM databases for studies published up to March 2013. In accordance with the inclusion and exclusion criteria, a total of six eligible studies were included in the pooled analyses. In the overall analysis, we did not observe any significant associations between the IL-8-251A>T polymorphism and oral cancer risk under any of the genetic models (all P > 0.05). In the stratified analysis by ethnicity, Caucasian individuals with genotype AA had a higher risk of oral cancer under the dominant model (OR = 1.35, 95 % CI 1.09-1.67, P = 0.006). This meta-analysis indicated that the IL-8-251A>T polymorphism was not associated with the susceptibility of oral cancer, while individuals in the Caucasian population with genotype AA had a higher risk of oral cancer under the dominant model.

Association of interleukin-8 gene polymorphisms with the risk of hepatocellular carcinoma

Interleukin-8 (IL8) polymorphisms have been implicated in several cancers, but their roles in the pathogenesis of hepatocellular carcinoma (HCC) are largely unknown. The present study was designed to explore the association between IL8 polymorphism and the risk of HCC in a Chinese population. Four single nucleotide polymorphisms (SNPs) of the IL8 gene -251A/T, +781C/T, -353A/T and +678T/C were analyzed in 205 HCC patients and 208 healthy controls in a Chinese population. Serum levels of IL8 were detected in HCC patients and healthy controls. The association between IL8 polymorphisms and HCC risk was measured using the adjusted odds ratios (OR) and their 95% confidence intervals (CI) from multiple logistic regression analysis. Haplotype analysis and gene-environment interaction analysis was also performed. The serum level of IL8 was significantly higher in HCC patients compared with healthy controls (P < 0.001). After adjusting for confounding factors, no significant associations were found between -251A/T, +781C/T, -353A/T and +678T/C and HCC risk (all P > 0.05). Haplotype analysis showed that A(251)-C(781)-A(353)-C(678) conferred decreased risk of HCC onset (adjusted OR 0.31, 95% CI 0.13-0.77). No significant interaction effects were found between the four SNPs and HBV infection, cirrhosis, gender smoking and alcohol consumption (all P > 0.05). No association between -251A/T, +781C/T, -353A/T and +678T/C of the IL8 gene and the risk of HCC was found in this Chinese population, and the SNPs did not display any interaction with several environmental factors with regard to HCC risk. However, it appears that A(251)-C(781)-A(353)-C(678) is perhaps a protective haplotype for HCC.

Association of duffy blood group gene polymorphisms with IL8 gene in chronic periodontitis

The antigens of the Duffy blood group system (DARC) act as a receptor for the interleukin IL-8. IL-8 plays an important role in the pathogenesis of chronic periodontitis due to its chemotactic properties on neutrophils. The aim of this study was to investigate a possible association of Duffy blood group gene polymorphisms with the -353T>A, -845T>C and -738T>A SNPs of the IL8 gene in chronic periodontitis. One hundred and twenty-four individuals with chronic periodontitis and 187 controls were enrolled. DNA was extracted using the salting-out method. The Duffy genotypes and IL8 gene promoter polymorphisms were investigated by PCR-RFLP. Statistical analyses were conducted using the Chi square test with Yates correction or Fisher's Exact Test, and the possibility of associations were evaluated by odds ratio with a 95% confidence interval. When analyzed separately, for the Duffy blood group system, differences in the genotype and allele frequencies were not observed between all the groups analyzed; and, in nonsmokers, the -845C allele (3.6% vs. 0.4%), -845TC genotype (7.3% vs. 0.7%) and the CTA haplotype (3.6% vs. 0.4%) were positively associated with chronic periodontitis. For the first time to our knowledge, the polymorphisms of erythroid DARC plus IL8 -353T>A SNPs were associated with chronic periodontitis in Brazilian individuals. In Afro-Brazilians patients, the FY*02N.01 with IL8 -353A SNP was associated with protection to chronic periodontitis.

Polymorphism of inflammatory genes and arsenic methylation capacity are associated with urothelial carcinoma

Chronic exposure to arsenic can generate reactive oxidative species, which can induce certain proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-8 (IL-8). TNF-α, IL-6 and IL-8 have been shown to be involved in the development and progression of various cancers, including bladder cancer. This study aimed to investigate the joint effect of the polymorphism of TNF-α -308 G/A, IL-6 -174 G/C, IL-8 -251 T/A and urinary arsenic profiles on urothelial carcinoma (UC) risk. This study evaluated 300 pathologically-confirmed cases of UC and 594 cancer-free controls. Urinary arsenic species were detected using high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. The polymorphism of TNF-α -308 G/A, IL-6 -174 G/C and IL-8 -251 T/A was determined using polymerase chain reaction-restriction fragment length polymorphism. The joint effects on UC risk were estimated by odds ratios and 95% confidence intervals using unconditional logistic regression. We found that the TNF-α -308 A/A and IL-8 -251 T/T polymorphisms were significantly associated with UC. Moreover, significant dose-response joint effect of TNF-α -308 A/A or IL-8 -251 T/T genotypes and arsenic methylation indices were seen to affect UC risk. The present results also showed a significant increase in UC risk in subjects with the IL-8 -251 T/T genotype for each SD increase in urinary total arsenic and MMA%. In contrast, a significant decrease in UC risk was found in subjects who carried the IL-8 -251 T/T genotype for each SD increase in DMA%.

Association between -251A>T polymorphism in the interleukin-8 gene and oral cancer risk: a meta-analysis

BACKGROUND

Emerging evidence showed that the most common functional polymorphism (-251A>T, rs4073) in the promoter region of the interleukin-8 (IL-8) gene is involved in the regulation of the activities of interleukin-8, thus increasing an individual's susceptibility to oral cancer; but individually published results are inconclusive. The aim of this meta-analysis was to investigate the associations between IL-8 -251A>T polymorphism and oral cancer risk.

METHODS

The PubMed, Embase, Web of Science and CBM databases were searched for all articles published up to October 1st, 2012 that addressed IL-8 -251A>T polymorphism and oral cancer risk. Statistical analyses were performed using STATA 12.0 software. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations.

RESULTS

Six case-control studies were included with a total of 1324 oral cancer cases and 1879 healthy controls. When all available studies were pooled into the meta-analysis, the results showed that the AA and AT genotypes of IL-8 -251A>T polymorphism were associated with increased risk of oral cancer (OR=1.23, 95% CI: 1.03-1.46, P=0.025; OR=1.25, 95% CI: 1.07-1.47, P=0.006; respectively). In the subgroup analysis by ethnicity, significant associations were observed between the AA and AT genotypes of IL-8 -251A>T polymorphism and increased risk of oral cancer among Caucasian populations (OR=1.40, 95% CI: 1.14-1.72, P=0.001; OR=1.29, 95% CI: 1.06-1.57, P=0.011; respectively). However, no statistically significant associations were found between IL-8 -251A>T polymorphism and oral cancer risk among Asian populations.

CONCLUSIONS

Results from the current meta-analysis indicate that the AA and AT genotypes of IL-8 -251A>T polymorphism might increase the risk of oral cancer, especially among Caucasian populations.

Risk modification of colorectal cancer susceptibility by interleukin-8 -251T>A polymorphism in Malaysians

AIM: To investigate the allele and genotype frequencies and associated risk of interleukin (IL)-8 -251T>A polymorphism on colorectal cancer (CRC) susceptibility risk.

METHODS: Peripheral blood samples of 255 normal controls and 255 clinically and histopathologically confirmed CRC patients were genotyped for IL-8 -251T>A polymorphism employing allele-specific polymerase chain reaction. The relative association of variant allele and genotypes with CRC susceptibility risk was determined by calculating the odds ratios (ORs). Corresponding χ² tests on the CRC patients and controls were carried out and 95% confidence intervals (CIs) were determined using Fisher’s exact test. The allele frequencies and its risk association were calculated using FAMHAP, haplotype association analysis software.

RESULTS: On comparing the frequencies of genotypes of patients and controls, the homozygous variant AA was significantly higher in CRC patients (P = 0.002) compared to controls. Investigation on the association of the polymorphic genotypes with CRC susceptibility risk, showed that the homozygous variant IL-8 -251AA had a significantly increased risk with OR 3.600 (95% CI: 1.550-8.481, P = 0.001). In the case of allele frequencies, variant allele A of IL-8 -251 showed a significantly increased risk of CRC predisposition with OR 1.32 (95% CI: 1.03-1.69, P = 0.003).

CONCLUSION: Variant allele and genotype of IL-8 (-251T>A) was significantly associated with CRC susceptibility risk and could be considered as a high-risk variant for CRC predisposition.

Disease severity in patients infected with Leishmania mexicana relates to IL-1β

Leishmania mexicana can cause both localized (LCL) and diffuse (DCL) cutaneous leishmaniasis, yet little is known about factors regulating disease severity in these patients. We analyzed if the disease was associated with single nucleotide polymorphisms (SNPs) in IL-1β (−511), CXCL8 (−251) and/or the inhibitor IL-1RA (+2018) in 58 Mexican mestizo patients with LCL, 6 with DCL and 123 control cases. Additionally, we analyzed the in vitro production of IL-1β by monocytes, the expression of this cytokine in sera of these patients, as well as the tissue distribution of IL-1β and the number of parasites in lesions of LCL and DCL patients. Our results show a significant difference in the distribution of IL-1β (−511 C/T) genotypes between patients and controls (heterozygous OR), with respect to the reference group CC, which was estimated with a value of 3.23, 95% CI = (1.2, 8.7) and p-value = 0.0167), indicating that IL-1β (−511 C/T) represents a variable influencing the risk to develop the disease in patients infected with Leishmania mexicana. Additionally, an increased in vitro production of IL-1β by monocytes and an increased serum expression of the cytokine correlated with the severity of the disease, since it was significantly higher in DCL patients heavily infected with Leishmania mexicana. The distribution of IL-1β in lesions also varied according to the number of parasites harbored in the tissues: in heavily infected LCL patients and in all DCL patients, the cytokine was scattered diffusely throughout the lesion. In contrast, in LCL patients with lower numbers of parasites in the lesions, IL-1β was confined to the cells. These data suggest that IL-1β possibly is a key player determining the severity of the disease in DCL patients. The analysis of polymorphisms in CXCL8 and IL-1RA showed no differences between patients with different disease severities or between patients and controls.

Leishmania mexicana is an intracellular parasite that causes two polarly opposed diseases: One is a self-limited disease, characterized by ulcerative lesions associated with a low infectious load, as found in patients with localized cutaneous leishmaniasis (LCL). And the other pole is characterized by a progressive disease where abundant parasites spread uncontrollably throughout the skin inside heavily infected phagocytic cells, as occurs in patients with diffuse cutaneous leishmaniasis (DCL). The cause of this severe form of the disease is unknown, although the early encounter between the parasite and the inflammatory response of the host possibly plays a decisive role in the disease outcome. We here show that polymorphism in the gene encoding IL-1β (−511 C/T) represents a variable influencing the risk to develop the disease for patients infected with Leishmania mexicana. In vitro experiments showed that monocytes of DCL patients secreted significantly higher levels of the proinflammatory cytokine IL-1β as compared to LCL patients. DCL patients also had augmented levels of IL-1β in serum, and the cytokine was diffusely distributed throughout lesions, which was correlated with the numbers of parasites in the lesions. We propose that IL-1β possibly plays a key role in establishing the disease severity in patients infected with Leishmania mexicana.

Effects of NFKB1 and NFKBIA gene polymorphisms on susceptibility to environmental factors and the clinicopathologic development of oral cancer

BACKGROUND

Oral cancer, which is the fourth most common cancer in Taiwanese men, is associated with environmental carcinogens. The possibility that genetic predisposition in nuclear factor-kappa B (NF-κB)-signaling pathways activation is linked to the development of oral squamous cell carcinoma (OSCC) requires investigation. The current study examines associations between polymorphisms within promoter regions of NFKB1 encoding NF-κB1 and NFKBIA encoding IkappaBalpha (IκBα) with both the susceptibility to develop OSCC and the clinicopathological characteristics of the tumors.

METHODOLOGY/PRINCIPAL FINDINGS

Genetic polymorphisms of NFKB1 and NFKBIA were analyzed by a real-time polymerase chain reaction (real-time PCR) for 462 patients with oral cancer and 520 non-cancer controls. We found that NFKB1 -94 ATGG1/ATGG2, -94 ATGG2/ATGG2, and the combination of -94 ATGG1/ATGG2 and ATGG2/ATGG2 genotypes NFKBIA -826 T (CT+TT) and -881 G (AG+GG) allelic carriages, were more prevalent in OSCC patients than in non-cancer participants. Moreover, we found that NFKB1 or NFKBIA gene polymorphisms seem to be related to susceptibility to develop oral cancer linked to betel nut and tobacco consumption. Finally, patients with oral cancer who had at least one -519 T allele of the NFKBIA gene were at higher risk for developing distant metastasis (P<.05), compared with those patients CC homozygotes.

CONCLUSIONS

Our results suggest that NFKB1 -94 ATTG2, NFKBIA -826 T, and -881 G alleles are associated with oral carcinogenesis. The combination of NFKB1 or NFKBIA gene polymorphisms and environmental carcinogens appears related to an increased risk of oral cancer. More importantly, the genetic polymorphism of NFKBIA -519 might be a predictive factor for the distal metastasis of OSCC in Taiwanese.

Impact of interleukin-8 gene polymorphisms and environmental factors on oral cancer susceptibility in Taiwan

OBJECTIVES

Interleukin-8 (IL-8), which is an angiogenic chemokine with a high expression level in tumor tissues, plays important roles in developing many human malignancies including oral squamous cell carcinoma (OSCC). This study was designed to examine the association of IL-8 gene polymorphisms with the susceptibility and clinicopathological characteristics of OSCC.

METHODS

A total of 270 patients with OSCC and 350 healthy control subjects were recruited. Four single nucleotide polymorphisms (SNPs) of IL-8 genes were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) genotyping analysis.

RESULTS

Results showed that four IL-8 SNPs (-251 T/A, +781 C/T, +1633 C/T, and +2767 A/T) were not associated with oral cancer susceptibility as well as clinicopathological parameters. But among 345 smokers, IL-8 polymorphisms carriers with betel quid chewing were found to have a 17.41- to 23.14-fold risk to have oral cancer compared to IL-8 wild-type carriers without betel quid chewing. Among 262 betel quid chewers, IL-8 polymorphisms carriers with smoking have a 10.54- to 20.44-fold risk to have oral cancer compared to those who carried wild type without smoking.

CONCLUSIONS

Our results suggest that the combination of IL-8 gene polymorphisms and environmental carcinogens might be highly related to the risk of oral cancer.

Relationship of interleukin-8 gene polymorphisms with hepatocellular carcinoma susceptibility and pathological development

BACKGROUND AND OBJECTIVES

Hepatocellular carcinoma (HCC) is one of the most frequent malignant neoplasms worldwide, and the second leading cause of death from cancer in Taiwan. Interleukin-8 (IL-8) is an angiogenic chemokine with important roles in the development and progression of many human malignancies including HCC. This study investigates the effects of single-nucleotide polymorphisms (SNPs) in the IL-8 gene on the susceptibility and clinicopathological characteristics of HCC.

METHODS

One hundred thirty-one HCC patients and 340 control subjects were analyzed for four IL-8 SNPs (-251 T/A, +781 C/T, +1633 C/T, and +2767 A/T) using PCR-RFLP genotyping analysis.

RESULTS

After adjusting for other confounders, results show that individuals with the IL-8 +781 T/T polymorphic genotype had a significantly lower risk of developing HCC than those with the wild-type (C/C) genotype (AOR = 0.346; 95% CI: 0.132-0.909). Multiple regression analysis showed that the presence of T/A or A/A at IL-8 -251 may indicate higher potential risk of hepatitis B infection (AOR = 2.847; 95% CI: 1.083-8.656). Additionally, these four IL-8 SNPs did not associate with liver-related clinicopathological markers in serum.

CONCLUSIONS

Genetic polymorphism at IL-8 +781 is an important factor in determining susceptibility to HCC in the Taiwanese population.

-251 T/A polymorphism of the interleukin-8 gene and cancer risk: a HuGE review and meta-analysis based on 42 case-control studies

The -251T/A (rs4073), a single nucleotide polymorphism, has been identified in the promoter region of the interleukin-8 (IL-8) gene. It's presence could influence the production of IL-8 protein by regulating the transcriptional activity of the gene. A large number of studies have been performed to evaluate the role of -251T/A polymorphism on various cancers, with inconsistent results being reported. In this paper, we summarized 13,189 cases and 16,828 controls from 42 case-control studies and attempted to assess the susceptibility of -251T/A polymorphism to cancers by a comprehensive meta-analysis. Pooled odds ratios and 95% confidence intervals were calculated by using the random-effects model. Publication bias, subgroup, and sensitivity analysis were also performed. Results showed that the carriers of the -251A allele had about a 12-21% increased risk for the reviewed cancer, in total. The carriers of -251A had an elevated risk to breast cancer, gastric cancer and nasopharyngeal cancer and a reduced risk to prostate cancer, but no evidence was found to indicate that the -251A allele predisposed its carriers to colorectal and lung cancers. When stratified separately by 'racial descent' and 'study design', it was found that the carriers of the -251A allele among the African group, Asian group and hospital-based case-control study group were at a higher risk for cancer, but not in European group and population-based case-control study. These results show that -251A allele is susceptible in the development of low-penetrance cancers.

Interleukin-8 gene promoter polymorphism (rs4073) may contribute to chronic periodontitis

BACKGROUND

The proinflammatory chemokine interleukin (IL)-8 is important in the regulation of the inflammatory response. Analyses of the single nucleotide polymorphism (SNP) reference sequence (rs) 4073 showed that the A allele upregulated IL-8 levels after stimulation with lipopolysaccharides. We investigated the association of the SNP rs4073 with chronic periodontitis.

METHODS

Genotyping was performed by a standard polymerase chain reaction-restriction fragment length polymorphism assay in 289 genomic DNA samples of healthy control subjects and patients with chronic periodontitis; analyses were adjusted by multivariate logistic regression modeling. A real-time polymerase chain reaction performance was used to detect levels of the IL-8 mRNA.

RESULTS

The analysis pointed to a statistically significant association of chronic periodontitis with the heterozygous TA genotype (P = 0.001); the results showed an increase in the frequency of the A allele in the diseased group (36% in the control group versus 48% in the periodontitis group). The higher levels of the IL-8 mRNA were found in the periodontitis group, mainly in individuals who presented the TA genotype (P = 0.03).

CONCLUSION

The SNP rs4073 was associated with chronic periodontitis in non-smoker Brazilian subjects because the frequency of the A allele was higher in the disease group than in the control group, and the TA genotype was associated with increased levels of IL-8 mRNA transcripts.

IL-8 -251A/T polymorphism is associated with decreased cancer risk among population-based studies: evidence from a meta-analysis

Growing evidence suggests that interleukin-8 (IL-8) play pivotal roles in the pathogenesis of cancer through the modulation of tumour immune response or enhanced angiogenesis. A single nucleotide polymorphism, -251A/T, has been identified in the promoter region of the IL-8 gene and has been shown to influence its production. Results from previous studies on the association of -251A/T polymorphism with different cancer types remained contradictory. To assess the effect of -251A/T of IL-8 on cancer susceptibility, we conducted a meta-analysis, up to May 2009, of 14,876 cases with different cancer types and 18,465 controls from 45 published case-control studies. Summary odds ratios and corresponding 95% confidence intervals (CIs) for IL-8 polymorphism and cancer were estimated using fixed- and random-effects models when appropriate. The AA/AT genotypes were associated with a significantly increased risk of nasopharyngeal carcinoma when compared with TT genotype (OR=1.48; 95% CI, 1.16-1.89). Moreover, significantly elevated risks were observed in 'other cancers', and also in African population when population is concerned. Interestingly, when stratified separately by population-based studies and hospital-based studies, significantly elevated risk was found among hospital-based studies (OR=1.21, 95% CI, 1.07-1.37), whereas significantly decreased risk was found among population-based studies (OR=0.90, 95% CI, 0.83-0.97). This meta-analysis shows that IL-8 -251A/T polymorphism may play a complex role in cancer development.

Potential biomarkers in saliva for oral squamous cell carcinoma

Sensitive and reliable early diagnostic markers for oral squamous cell carcinoma (OSCC) remain unavailable. Early identification of recurrence for OSCC is also a challenge. Unlike the other deep cancers, OSCC is located in oral cavity. The DNA, RNA, and protein derived from the living cancer cells and inflammatory cells then can be conveniently obtained from saliva. High-throughput genomic and proteomic approaches have been carried out to identify the potential biomarkers in body fluids such as saliva and blood for diagnosis and prognosis of OSCC. This article reviewed the recently identified biomarkers from saliva for OSCC. In addition, the biomarkers which have been correlated with OSCC tumor malignancy by molecular pathology analysis are also described. Finally, the potential biomarkers that have been demonstrated to associate with the malignant OSCC may be used for salivary screening for high-risk patients are suggested. This article may help to identify the potential biomarkers for screening and the molecular pathology analysis for high-risk patients of OSCC. Effective screening to identify high-risk patients can allow the clinician to provide the appropriate treatment without delay and to reduce the recurrence of OSCC.

IL-8 -251 T > A polymorphism is associated with bladder cancer susceptibility and outcome after BCG immunotherapy in a northern Indian cohort

BACKGROUND AND AIMS

Chemokines and transcription factor NF-kappaB play a pivotal role in development of carcinoma of the bladder (CaB). The present study was conducted to analyze the association of chemokines IL-8 -251 T>A and +678 C>T and NF-kappaB -94 (ATTG) insertion/deletion polymorphisms with the risk of CaB and outcome after bacillus Calmette-Guerin (BCG) immunotherapy in a cohort of northern India.

METHODS

Histologically confirmed 205 CaB cases and 270 controls were included. Of these, 71 patients were treated with BCG immunotherapy. Genotyping was done using allele-specific PCR methodology.

RESULTS

The variant genotype (AA) of IL-8 -251 polymorphism was associated with more than 2-fold risk of CaB (OR 2.12; p = 0.003; 95% CI 1.28-3.52). None of the other genotypes showed association with CaB risk. Subsequently, the diplotype -251A/+678T demonstrated a 1.8-fold increased risk for CaB (OR 1.84, 95% CI 1.37-2.47). Furthermore, -251 AA genotypes reduced the risk of recurrence after BCG immunotherapy (AA; HR 0.12; 95% CI 0.04-0.41). Subsequently, improved recurrence-free survival (mean recurrence-free survival for GG, GA and AA genotypes was 24, 39 and 53 months respectively). Similarly, NF-kappaB ATTG Ins/Ins genotype was at reduced risk of recurrence after BCG treatment compared to Del/Del genotype, which exhibited a 2.5-fold increased risk of recurrence in patients treated with BCG immunotherapy (HR, 2.53; 95% CI 1.00-6.36). Subsequently, mean recurrence-free survival (Ins/Ins, 41; Ins/Del, 44 and Del/Del, 10 months; log rank, 0.030).

CONCLUSIONS

Our results suggested that the IL-8 -251 T>A polymorphism may be a relevant host susceptibility factor for bladder carcinoma development and may influence outcome after BCG immunotherapy. Similarly, NF-kappaB ATTG polymorphism may also modify risk-free survival of BCG-treated patients.

Association of interleukin-8 with cachexia from patients with low-third gastric cancer

Background. Interleukin (IL)-8 has been implicated in the development of cancer cachexia. The polymorphism of IL-8 gene, which may affect the production level of IL-8, may be associated with cancer cachexia. Methods. The serum IL-8 level in our study was examined by radioimmunoassay. We also analyzed single nucleotide polymorphisms (SNPs) −251 A/T and +781 C/T of IL-8 gene, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results. The serum levels of IL-8 were significantly elevated in patients with low-third gastric cancer compared with controls, and were further up-regulated in patients with cachexia than those without (Z = −3.134, P = .002). A significantly increased frequency of +781 T allele was noted in patients with cachexia (OR = 2.247, 95% CI: 1.351–3.737, P = .002). The +781 TT genotype was observed to be associated with a significantly increased risk of cachexia (OR = 3.167, 95% CI: 1.265–7.929, P = .011), and with odds ratio of 3.033 (95% CI: 1.065–8.639, P = .038) for cachexia after adjusting for potential confounding factors. Meanwhile, haplotype analysis indicated a borderline positive association between T²⁵¹T⁷⁸¹ haplotype and cachexia as compared with the T²⁵¹C⁷⁸¹ haplotype (OR = 4.92, 95% CI: 1.00–24.28;, P = .053). Conclusions. IL-8 appears to be associated with cachexia from patients with low-third gastric cancer.

Implications of cytokine gene polymorphisms on the orchestration of the immune response: lessons learned from oral diseases

Over the past 10 years, a plethora of information concerning the influence of gene polymorphisms on cytokine expression has been made available in the literature. Significant contribution to this field has come from studies of oral diseases, one of the widest spread health problems in the world, affecting hundreds of millions worldwide. Here we will discuss the importance of studies of gene polymorphism towards the identification of susceptible groups or prognostic indicators of oral disease. Additionally, we will highlight the differences in data obtained from genetically diverse populations and review the application of cytokine gene polymorphisms studies in oral diseases in autoimmune processes and parasitic infections.

Chemokine–chemokine receptors in cancer immunotherapy

A surge in interest in the chemokine–chemokine receptor network is probably related to the expanding roles that chemokines have now been identified to play in human biology, particularly immunity. Specific tissue microenvironments express distinct chemokines and both hematopoietic and nonhematopoietic cells have receptor expression profiles that permit the coordinated trafficking and organization of cells within these specific tissues. Since the chemokine network plays critical roles in both the function of the immune system and the progression of cancer, it is an attractive target for therapeutic manipulation. This review will focus on chemokine and chemokine receptor network-related therapeutic interventions that utilize host–tumor interactions particularly involving the immune system.

Association of leptin -2548G/A and leptin receptor Q223R polymorphisms with increased risk for oral cancer

PURPOSE

We investigated the possible association of DNA polymorphisms -2548G/A and Q223R in the leptin (LEP) and leptin receptor (LEPR) genes, respectively, which both affect the amount of circulating cytokine-type hormone leptin, with risk for development of oral cancer.

METHODS

Polymerase chain reaction-based restriction analysis was performed in DNA samples of 150 patients with oral squamous cell carcinoma (OSCC) and 152 healthy control subjects of equivalent gender, age, and ethnicity (Greeks and Germans).

RESULTS

Compared to controls, the homozygous high gene expression genotype A/A of the LEP -2548G/A polymorphism was significantly increased in the subgroups of patients with advanced cancer stages (P = 0.0001; OR 9.0, 95% CI 2.62-30.89), with a positive family history of cancer (P = 0.0346; OR 3.55, 95% CI 1.15-11.01), without tobacco abuse (P = 0.0051; OR 9.69, 95% CI 1.03-91.24), and without alcohol abuse (P = 0.0472; OR 2.16, 95% CI 0.87-5.37). The homozygous low-leptin-binding genotype G/G of the LEPR Q223R polymorphism was strongly associated with an increased risk for OSCC for all patients (P = 0.0028; OR 4.11, 95% CI 1.30-12.97) as well for most of the patient subgroups.

CONCLUSIONS

The above findings are consistent with the growth-promoting role of leptin in cancer and its induction effect on angiogenesis and metastasis. This is the first study indicating the association of these LEP and LEPR gene polymorphisms with increased risk for OSCC.

Genetic association of cytokine DNA polymorphisms with head and neck cancer

Mutations in oncogenes or tumor suppressor genes, as well as environmental factors such as tobacco chewing or smoking, poor oral hygiene, ill-fitting dental appliances, infection by certain HPV types, or alcohol abuse, seem to be involved in the multifactorial process of carcinogenesis in head and neck. Recently, several genetic association studies have indicated that common DNA polymorphisms in low penetrance genes may affect the susceptibility of an individual to malignancy. Cytokines are an important group of proteins that regulate and mediate inflammation and angiogenesis. Tumor growth, invasion and metastasis are facilitated when there is a deregulation in their production. Cytokines include interleukins (ILs), tumor necrosis factors (TNFs) and certain growth factors (GFs). A number of genetic association studies have recently investigated the putative correlation between functional DNA polymorphisms in cytokine genes and head and neck carcinomas. This review discusses the findings of such studies in oral, nasopharyngeal and esophageal squamous cell carcinomas. Extensive research has indicated that functional polymorphisms affecting gene expression of IL-4,-6,-8,-10 as well as TNF-alpha are strongly associated with increased risk for oral cancer. Gene expression of TNF-alpha seems to be associated also with esophageal carcinomas, while for nasopharyngeal cancer the picture is yet unclear. It is generally believed that such genetic association studies will gradually increase our knowledge regarding the predisposed manifestation and advancement of these malignancies in the head and neck region.

A metalloproteinase-9 polymorphism which affects its expression is associated with increased risk for oral squamous cell carcinoma

AIM

In light to recently found contribution of factors associated with angiogenesis, thrombosis and inflammation to carcinogenesis, we investigated the possible association of metalloproteinase-9 (MMP-9) with increased risk of oral cancer.

METHODS

In DNA samples of 152 patients with oral squamous cell carcinoma and 162 healthy controls of comparable ethnicity, age and sex, we studied the -1562 C/T polymorphism in the MMP-9 gene promoter, which affects its transcription.

RESULTS

The detected frequency for the high expression T allele in the patients' group was significantly increased in comparison to that of the control group (22% versus 15%, respectively; P<0.05). This difference was due to the relative increase of C/T heterozygotes in the group of patients, in comparison to controls (P<0.05, 95% OR 1.92, CI 1.21-3.06). The same pattern of significance was observed between controls and the subgroups of patients with initial (I & II) stages of cancer, without positive family history of cancer or thrombophilia, with smoking and alcohol abuse habits.

CONCLUSIONS

The investigated MMP-9 polymorphism has a strong association with increased risk for developing oral cancer in a subset of the general population. These results are in accordance to previous studies of constitutive expression and secretion of MMP-9 in invasive oral carcinoma cell lines. The observation that T allele carriers have an increased risk for developing oral cancer only in initial stages, but not in advanced ones, may be due to the role of MMP-9 in the inhibition of angiogenesis by generating angiostatin from plasminogen.

Interleukin-8 promoter polymorphism -251A/T is a risk factor for age-related macular degeneration

BACKGROUND/AIMS

To determine whether four expression-related cytokine polymorphisms are associated with age-related macular degeneration (AMD).

METHODS

DNA from 478 cases with AMD and 555 normal controls was genotyped for the pro-inflammatory IL1beta -511C/T, IL6 -174C/G, IL8 -251A/T and anti-inflammatory IL10 -1082G/A cytokine polymorphisms using the 5' nuclease TaqMan(R) assay for allelic discrimination. Associations with AMD were analysed using allelic frequencies.

RESULTS

The -251A allele of the IL8 promoter gene polymorphism was more prevalent in AMD patients than controls (p = 0.037, OR = 1.21, 95% CI = 1.01 to 1.44). Adjusting for age, sex, body mass index (BMI), current smoking and past smoking status did not alter the AMD association significantly (corrected p value = 0.043, OR = 1.23, 95% CI = 1.0 to 1.50).

CONCLUSION

The pro-inflammatory homozygous IL8 -251AA genotype is an important risk factor for AMD. This may have implications for future therapy with biological agents that could target this cytokine.

Gene expression polymorphisms of interleukins-1 beta, -4, -6, -8, -10, and tumor necrosis factors-alpha, -beta: regression analysis of their effect upon oral squamous cell carcinoma

PURPOSE

Functional DNA polymorphisms affecting gene expression and serum or saliva levels of interleukins IL-1 beta,-4,-6,-8,-10 and tumor necrosis factors TNF-alpha,-beta have been associated with increased risk for the development of oral squamous cell carcinoma (OSCC). The present retrospective case-control study examines possible interactions between seven cytokine genotype polymorphisms and their combinatory effect in predicting the occurrence of OSCC in Caucasians.

METHODS

Three hundred and thirty Greeks and Germans were studied, consisting of 162 OSCC cases and 168 healthy controls of comparable age, gender, and ethnicity. A series of multivariate logistic regression models, adjusted for age and gender, was constructed in order to assess the contribution of homozygous or heterozygous variant genotypes of polymorphisms IL-1 beta (+3953C/T), IL-4 (-590C/T), IL-6 (-174G/C), IL-8 (-251A/T), IL-10 (-1082A/G), TNF-alpha (-308G/A) and TNF-beta (+252G/A) upon overall, early and advanced stages of OSCC development.

RESULTS

The contribution of TNF-alpha and IL-6 was consistent and robust in almost all models constructed. Furthermore, when the mode of inheritance of each variant allele was taken into account in a "biological" multivariate logistic regression model, four polymorphisms emerged as primary predictors for overall stages of OSCC: TNF-alpha (OR = 15.27; 95% CI = 7.30-31.96), IL-6 (OR = 8.33; 95% CI = 3.95-17.58), IL-8 (OR = 3.54; 95% CI = 1.69-7.43) and IL-10 (OR = 2.65; 95% CI = 1.28-5.46). Finally, IL-1 beta, IL-4 and TNF-beta polymorphisms were not primary predictors of OSCC development in all constructed models.

CONCLUSIONS

This study revealed the highly significant contributions of two out of seven studied cytokines (IL-6 and TNF-alpha) in the occurrence of OSCC. Based on these findings and previous reports, possible stoichiometrical interactions of cytokines leading to OSCC development are discussed.

The chemokine network. II. On how polymorphisms and alternative splicing increase the number of molecular species and configure intricate patterns of disease susceptibility

In this second review on chemokines, we focus on the polymorphisms and alternative splicings and on their consequences in disease. Because chemokines are key mediators in the pathogenesis of inflammatory, autoimmune, vascular and neoplastic disorders, a large number of studies attempting to relate particular polymorphisms of chemokines to given diseases have already been conducted, sometimes with contradictory results. Reviewing the published data, it becomes evident that some chemokine genes that are polymorphic have alleles that are found repeatedly, associated with disease of different aetiologies but sharing some aspects of pathogenesis. Among CXC chemokines, single nucleotide polymorphisms (SNPs) in the CXCL8 and CXCL12 genes stand out, as they have alleles associated with many diseases such as asthma and human immunodeficiency virus (HIV), respectively. Of CC chemokines, the stronger associations occur among alleles from SNPs in CCL2 and CCL5 genes and a number of inflammatory conditions. To understand how chemokines contribute to disease it is also necessary to take into account all the isoforms resulting from differential splicing. The first part of this review deals with polymorphisms and the second with the diversity of molecular species derived from each chemokine gene due to alternative splicing phenomena. The number of molecular species and the level of expression of each of them for every chemokine and for each functionally related group of chemokines reaches a complexity that requires new modelling algorithms akin to those proposed in systems biology approaches.

The 1040C/T polymorphism influencing thermal stability and activity of thrombin activatable fibrinolysis inhibitor is associated with risk for oral cancer

No studies thus far have investigated the contribution of thrombin activatable fibrinolysis inhibitor (TAFI) to oral oncogenesis. We studied the activity-related 1040C/T polymorphism in 150 patients with oral cancer and 138 healthy controls matched by age, gender, and ethnicity. The increased-activity T allele frequency was significantly reduced in patients compared with controls (28.7% vs. 37.0%, P < 0.05). T/T homozygotes had about half the probability of developing oral cancer (O.R. 0.39, 95%C.I. 0.13-1.14), while no significant difference was observed in C/T heterozygotes. The observed prophylactic effect of increased TAFI activity might result from reduction of plasmin and inhibition of extracellular matrix dissolution.

Genetic variation in interleukin-10 gene and risk of oral cancer

BACKGROUND

Common genetic variants in immune and inflammatory response genes can affect the risk of developing oral cancer. Interleukin-10 (IL-10) is an immunosuppressive cytokine which may facilitate development of cancer by supporting tumor escape from the immune response. Inter-individual variations in IL-10 production were genetically contributed to polymorphisms within IL-10 promoter region. We determined whether single nucleotide polymorphisms (SNPs) at positions -1082 A/G (rs1800870), -819 T/C (rs1800871) and -592 A/C (rs1800872) in the IL-10 gene promoter were involved in predisposing an individual to oral cancer.

METHODS

We analyzed 3 SNPS of IL-10 gene promoter in 280 patients with oral cancer and 300 age and sex matched controls in a Chinese population, using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy.

RESULTS

There were significant differences in the genotype and allele distribution of -1082 A/G (rs1800870) polymorphism of the IL-10 gene among cases and controls. The -1082 G alleles carriers were associated with a significantly increased risk of oral cancer compared with the non-carriers (OR=1.821, 95% CI, 1.329-2.496, P<0.001). Haplotype analysis revealed that the GCC haplotype (defined by SNPs at positions -1082, -819 and -592) of IL-10 gene conveys the highest risk for oral cancer compared with the ATA haplotype (OR=1.716; 95% CI, 1.230-2.395; P=0.001).

CONCLUSION

IL-10 gene promoter -1082 A/G (rs1800870) polymorphism, and its haplotype are significantly associated with the risk of oral cancer. Our data suggests that IL-10 gene plays an important role in the development of oral cancer.