HLA class II polymorphisms as prognostic biomarkers for right and left-sided colon cancer.

BACKGROUND: Colon cancer (CC) is one of the most common malignancies worldwide. Characterization of new prognostic biomarkers for right-sided CC (RCC) and left-sided CC (LCC) may contribute to improving early detection. An association of human leukocyte antigens class II (HLA-II) with the predisposition to CC was suggested. AIM OF THE STUDY: We evaluated the association of DRB1 and DQB1 with the risk of LCC and RCC. PATIENTS AND METHODS: Our study comprised 93 CC patients and 100 healthy controls. Genotyping of HLA class II alleles were performed by the Polymerase Chain Reaction Sequence-Specific Primers (PCR-SSP). RESULTS: DRB1*03 was positively associated with CC. In contrast, DRB1*11, DRB1*13, DQB1*03, and DQB1*05 were negatively linked to CC. Haplotype analysis revealed that DRB1*04-DQB1*04 and DRB1*09-DQB1*02 were positive, while DRB1*01-DQB1*05, DRB1*04-DQB1*03, DRB1*07-DQB1*02, DRB1*11-DQB1*03, DRB1*11-DQB1*05, and DRB1*13-DQB1*06 were negatively associated with CC. For sigmoid CC, DRB1*13, DRB1*11, and DQB1*05 were negative, while DRB1*04-DQB1*02, and DRB1*07-DQB1*03 were positively associated. DRB1*03 and DRB1*04-DQB1*04 were positive, while DRB1*11 and DQB1*03 were negatively linked to RCC. According to the LCC, DRB1*07, DRB1*11, DQB1*03, DQB1*05, and DRB1*07-DQB1*02 were negative. In contrast, DRB1*09-DQB1*02 was positively associated with LCC. Stratified analysis revealed that DRB1*11 is associated with higher risk of metastasis in CC and sigmoid CC, and tolerance to treatment in RCC. DQB1*03 was associated with lymph-node invasion in CC. CONCLUSION: DRB1 and DQB1 polymorphisms could be used as future biomarkers for the early detection of subjects at a higher risk of developing RCC and LCC, metastasis in sigmoid CC, and tolerance to treatment in RCC.

Decreased risk of ovarian cancer associated with rs9898876 sex hormone-binding globulin gene variant.

BACKGROUND: Ovarian cancer (OC) is one of the most common gynecologic cancers,with significant morbidity and mortality. The risk of OC is influenced by hormone status, of which sex hormone-binding globulin (SHBG), which influences the serum availability of steroid sex hormones, is implicated in the pathogenesis and evolution of OC. The aim of this study is to evaluate the involvement of common SHBG gene variants in OC susceptibility and evolution. MATERIALS: A case control study including 71 OC patients and 74 cancer-free controls, who were genotyped for rs9898876, rs13894, rs1799941 and rs6257 SHBG SNP. Genotyping was done by the allelic discrimination method, using VIC- and FAM-labeled primers. RESULTS: The minor allele frequencies of rs9898876, rs13894, rs1799941 and rs6257 SHBG SNP was comparable between OC cases and control women, implying no significant associations of the tested variants and overall OC risk. Taking homozygous wild-type genotype as reference (OR = 1.00), heterozygous rs9898876 (G/T), and minor allele-carrying genotypes [G/T + T/T] were associated with reduced risk of OC. While rs9898876 heterozygosity (G/T) was predictive of OC occurrence, no significant association of the remaining three tested SNPs was noted with altered risk of OC. Irrespective of FIGO staging, the four tested SHBG SNPs were not associated with the clinical progression of OC. CONCLUSIONS: In conclusion, SHBG rs9898876 is associated with a decreased risk of OC, and thus constitutes a potential diagnostic biomarker of OC.

Western influenced lifestyle and Kv2.1 association as predicted biomarkers for Tunisian colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is the third most diagnosed malignancy worldwide. The global burden is expected to increase along with ongoing westernized behaviors and lifestyle. The etiology of CRC remains elusive and most likely combines environmental and genetic factors. The Kv2.1 potassium channel encoded by KCNB1 plays a collection of roles in malignancy of cancer and may be a key factor of CRC susceptibility. Our study provides baseline association between Tunisian CRC and interactions between KCNB1 variants and lifestyle factors. METHODS: A case-control study involving 300 CRC patients, and 300 controls was conducted Patients were carefully phenotyped and followed till the end of study. KCNB1 genotyping was confirmed by Sanger sequencing. Bivariate and multivariable logistic regression analyses were used to assess the clinical status, lifestyle and study polymorphisms association with CRC. RESULTS: We noted significant gender association with CRC occurrence. Moreover, CRC risk increases with high meat and fat consumption, alcohol use and physical activity (PA). Carriage of rs1051296 A/G and both rs11468831 ins/del and del/del genotypes (p < 0.001) were significantly associated with CRC risk. Analysis according to gender reveals correlation of rs1051295 A/G, rs11468831 non ins/ins (p = 0.01) with CRC susceptibility regardless of patients' gender while rs3331 T/C (p = 0.012) was associated with females. Stratification study according to malignancy site; Rectal Cancer (RC) and Colon Cancer (CC), reveals increasing RC risk by gender and high meat and fat consumption, alcohol use and PA. However, additional association with high brine consumption was noted for CC. The rs1051295 A/G (p = 0.01) was associated with RC risk. Increased CC risk was associated with carriage of rs1051295 A/G, rs11168831 (del/del) and (ins/del) genotypes. CONCLUSION: The risk of CRC increases with modifiable factors by Western influences on Tunisian lifestyle such as alcohol use, high fat consumption and possibly inadequate intake of vegetables. In addition, KCNB1 polymorphisms also markedly influence CRC susceptibility. Our study establishes key elements of a baseline characterization of clinical state, Western influenced lifestyle and KCNB1 variants associated with Tunisian CRC.

Identification of novel advanced glycation end products receptor gene variants associated with colorectal cancer in Tunisians: A case-control study.

A central role for advanced glycation end products (AGE) and their receptor (RAGE) in the pathogenesis of multiple cancer types, including colorectal cancer (CRC) was reported. We investigated the association between CRC and rs2853807, rs77170610, rs184003, rs1035798, rs2070600, rs1800684, rs1800624, and rs1800625 RAGE gene (AGER) polymorphic variants. Study subjects comprised 293 CRC patients [186 colon cancer (CC) and 107 rectal cancer (RC)] patients), and 264 age-, gender-, BMI-, and ethnicity-matched controls. Minor allele frequency (MAF) of rs77170610 and rs1800625 were significantly lower, while MAF of rs1035798 was significantly higher in CRC patients compared to control subjects, which was associated with reduced and increased risk of CRC, respectively; MAF of the remaining variants was comparable between CRC patients and controls. Significant difference in the distribution of rs2853807 and rs77170610 genotypes was seen between CRC patients and controls, with both variants associated with decreased risk of CRC. Comparison of the distribution of minor allele-carrying genotypes in CC and RC patient subgroups revealed lack of significant difference in the distribution of these genotypes between the patient subgroups. In view of the lack of LD between rs2853807 and rs77170610 with other variants, six-locus (rs184003, rs1035798, rs2070600, rs1800684, rs1800624, rs1800625) haplotypes were constructed. Haplotype analysis did not identify any specific 6-locus AGER haplotype associated with CRC. In conclusion, AGER gene rs2853807 and rs77170610 variants rs77170610 are associated with altered risk of CRC in Tunisians, but with no discrimination between CC and RC types.

Interleukin-17A polymorphisms predict the response and development of tolerance to FOLFOX chemotherapy in colorectal cancer treatment.

Polymorphic variants in IL-17A gene were differentially associated with colorectal cancer (CRC) susceptibility but their link with response and toxicity to CRC treatment have not yet been evaluated. We investigated association between seven IL-17A variants with the response and toxicity to CRC treatment in 294 patients with CRC. IL-17A genotyping was done by real-time PCR. MAF of rs3748067 was significantly higher in CRC cases resistant to FOLFOX treatment (R+) than non resistant (R-). Significantly higher rs3804513 MAF was noted in R+ versus R- colon cancer (CC). Higher rs2275913 and rs10484879, and reduced rs3804513 MAF were seen in rectal cancer (RC) tolerant to FOLFOX (T+) compared to (T-) patients. Strong association of rs3819025, rs3804513, and rs7747909 was found with tolerance to RC treatment. rs3748067 was associated with FOLFOX tolerance in CC but not RC. Significant higher frequency of AGGCAGG and GAGCAGG haplotypes was seen among R + CC, thus assigning non-favorable nature to these haplotypes. Higher and lower frequencies of GAGTAAG and AGGCTGA haplotypes, respectively, were observed in T + RC, thereby assigning FOLFOX-tolerant and non-tolerant nature to these haplotypes. The obtained results suggest that IL-17A variants and haplotypes may be a target for future management of CRC treatment.

Increased risks between TLR2 (-196 to -174 ins/del) and TLR3 1377C>T variants and head and neck cancers in Tunisia.

INTRODUCTION: Previous studies have highlighted the importance of polymorphisms of toll-like receptors (TLRs) in the pathogenesis of certain cancers, including head and neck cancers (HNC). AIM OF THE STUDY: The aim of this study was to evaluate the association of TLR2 (-196 to -174 ins/del) and TLR3 (1377 C>T) as potential risk factors for HNC in Tunisians. MATERIAL AND METHODS: A case-control study including 246 HNC patients (174 nasopharyngeal carcinoma - NPC and 72 laryngeal cancer - LC) and 250 healthy controls. Genotyping was done by using PCR and PCR-RFLP methods. RESULTS: Higher minor allele frequencies of TLR2 (-196 to -174 ins/del) and TLR3 1377 C>T polymorphisms were seen in HNC, NPC, and LC compared to controls. In addition, higher increased HNC, NPC, and LC risk was associated with TLR2 ins/del and TLR2 del/del genotypes (p < 0.0001). Positive association with HNC, NPC, and LC risk was seen with TLR2 del-containing genotypes (ins/del + del/del) (p < 0.0001). The T/T genotype of TLR3 is associated with HNC, NPC, and LC susceptibility (p < 0.0001). Positive association with HNC and NPC risk was seen with TLR3 T allele carriers (C/T + T/T) (p < 0.0001). Increased frequency of T-ins, C-del, and T-del haplotypes was revealed in HNC and NPC cases than healthy controls; however, T-del was significantly higher in LC cases. CONCLUSIONS: Our results demonstrate an increased risk of HNC, NPC, and LC with TLR2 ins/del, TLR2 del/del, and TLR3 T/T genotypes. And positive association with T-ins, C-del, and T-del haplotypes with HNC and NPC and T-del haplotype with LC.

Transforming growth factor beta 1 polymorphisms and haplotypes associated with breast cancer susceptibility: A case-control study in Tunisian women.

Variable association of transforming growth factor beta 1 (TGFß1) in breast cancer (BC) pathogenesis was documented, and the contribution of specific TGFB1 polymorphisms to the progression of BC and associated features remains poorly understood. We investigated the contribution of TGFB1 rs1800469, rs1800470, rs1800471, and rs1800472 variants and 4-locus TGFB1 haplotypes on BC susceptibility, and pathological presentation of BC subtypes. Study subjects comprised 430 female BC cases, and 498 cancer-free control women. BC-associated pathological parameters were also evaluated for correlation with TGFB1 variants. Results obtained showed that the minor allele frequency (MAF) of rs1800471 (+74G>C) was higher seen in BC cases than in control subjects, and was associated with increased risk of BC. Significant differences in rs1800471 and rs1800469 (-509C>T) genotype distribution were noted between BC cases and controls, which persisted after controlling for key covariates. TGFB1 rs1800472 was positively, while rs1800470 was negatively associated with triple negativity, while rs1800470 positively correlated with menarche, but negatively with tumor size and molecular type, and rs1800469 correlated positively with menstrual irregularity, distant metastasis, nodal status, and hormonotherapy. Heterogeneity in LD pattern was noted between the tested TGFB1 variants. Four-locus (rs1800472-rs1800471-rs1800470-rs1800469) Haploview analysis identified haplotype TGCT to be negatively associated, and haplotypes CGTT and CCCC to be positively associated with BC. This association of CGTT and CCCC, but not TGCT, with BC remained significant after controlling for key covariates. In conclusion, TGFB1 alleles and specific genotypes, and 4-locus TGFB1 haplotypes influence BC susceptibility, suggesting dual association imparted by specific SNP, consistent with dual role for TGFB1 in BC pathogenesis.

Common matrix metalloproteinase-2 gene variants and altered susceptibility to breast cancer and associated features in Tunisian women.

A role for matrix metalloproteinase polymorphisms in breast cancer development and progression was proposed, but with inconclusive results. We assessed the relation of matrix metalloproteinase-2 variants with breast cancer and related phenotypes in Tunisians. This case-control retrospective study involved 430 women with breast cancer and 498 healthy controls. Genotyping of matrix metalloproteinase-2 rs243866, rs243865, rs243864, and rs2285053 was analyzed by allelic exclusion. The minor allele frequency of rs2285053 was significantly lower in women with breast cancer cases as compared to control women; minor allele frequencies of the remaining single-nucleotide polymorphisms were similar between cases and control women. The distribution of rs243865 and rs2285053 genotypes was significantly different between breast cancer patients and control subjects. This persisted when key covariates were controlled for. None of the matrix metalloproteinase-2 variants were associated with estrogen receptor positivity, progesterone receptor positivity, or with double estrogen receptor-progesterone receptor positivity in breast cancer patients. Matrix metalloproteinase-2 rs243866, rs243865, and rs243864 were positively associated with menstrual irregularity and histological type, while rs243866 and rs2285053 were negatively associated with menarche and nodal status. In addition, rs2285053 was negatively associated with triple negativity, tumor size, distance metastasis, molecular type, and chemotherapy. Haploview analysis revealed high linkage disequilibrium between matrix metalloproteinase-2 variants. Four-locus Haploview analysis identified haplotypes GCTT and GTTC to be negatively associated with breast cancer, which remained statistically after controlling for key covariates. Matrix metalloproteinase-2 alleles and genotypes, along with four-locus haplotypes, are related to reduced susceptibility to breast cancer in Tunisian women, suggesting a protective effect.

Relationships Between Ion Channels, Mitochondrial Functions and Inflammation in Human Aging.

Aging is often associated with a loss of function. We believe aging to be more an adaptation to the various, and often continuous, stressors encountered during life in order to maintain overall functionality of the systems. The maladaptation of a system during aging may increase the susceptibility to diseases. There are basic cellular functions that may influence and/or are influenced by aging. Mitochondrial function is amongst these. Their presence in almost all cell types makes of these valuable targets for interventions to slow down or even reserve signs of aging. In this review, the role of mitochondria and essential physiological regulators of mitochondria and cellular functions, ion channels, will be discussed in the context of human aging. The origins of inflamm-aging, associated with poor clinical outcomes, will be linked to mitochondria and ion channel biology.

Association of common IL-10 promoter gene variants with the susceptibility to head and neck cancer in Tunisia

Background/aim: We investigated the association of three IL-10 promoter single-nucleotide polymorphisms and altered IL-10 plasma levels with the risk of head and neck cancer (HNC). Materials and methods: Study subjects comprised 194 HNC patients [137 nasopharyngeal cancer (NPC) and 57 laryngeal cancer (LC)], and 263 healthy controls. Genotyping of rs1800896 (-1082A>G), rs1800871 (-819C>T), and rs1800872 (-592A>C) IL-10 variants was performed by real-time PCR; IL-10 levels were measured by enzyme amplified immuno sensitivity assay (EAISA). Results: Study subjects comprised 194 HNC patients [137 nasopharyngeal cancer (NPC) and 57 laryngeal cancer (LC)], and 263 healthy controls. Genotyping of rs1800896 (-1082A>G), rs1800871 (-819C>T), and rs1800872 (-592A>C) IL-10 variants was performed by real-time PCR; IL-10 levels were measured by enzyme amplified immuno sensitivity assay (EAISA). Conclusion: Our results demonstrate that IL-10-1082, IL-10-819, and IL-10-592 variants, and haplotypes GC and GT constitute biomarkers for early detection of HNC, especially NPC subtype. IL-10 -819T/C and TA haplotype may be used as biomarkers for early detection of LC.

Association of interleukin-17A polymorphisms with the risk of colorectal cancer: A case-control study.

BACKGROUND: Interleukin (IL)-17A is proinflammatory cytokine produced by Th17 cells, which play key, but sometimes inconsistent role in autoimmunity and cancer. Polymorphic variants in IL-17A gene were differentially associated with susceptibility to cancer, including colorectal cancer (CRC). AIM: We investigated the association between six IL-17A gene variants (rs3819024, rs2275913, rs3819025, rs10484879, rs7747909, and rs3748067) with CRC susceptibility in Tunisians. SUBJECTS AND METHODS: Retrospective case-control study. Study subjects comprised 293 patients with CRC, and 268 age-, gender-, and BMI-matched healthy controls. IL-17A genotyping was done by real-time PCR, with defined clusters. RESULTS: Of the seven tested IL-17A tag-SNPs, minor allele frequency (MAF) of rs10484879 was significantly higher in CRC patients than control subjects. Heterozygous rs10484879 [OR (95% CI) = 2.63 (1.64-4.21)] was associated with higher risk, while carriage of heterozygous rs3748067 genotype was associated with reduced risk of CRC [OR (95% CI) = 0.56 (0.37-0.84)], respectively. Carriage of rs10484879 minor allele correlated with positive family history of CRC and other cancers (P = 0.002), CRC staging (P = 0.044), CRC treatment (P = 0.038), and with chemo body reaction (P = 0.001). Of the 7 IL-17A variants, 4 were in linkage disequilibrium, hence allowing for construction of 4-locus haplotypes. Varied linkage disequilibrium (LD) was noted between the even tested IL-17A variants, and further analysis was limited to only 4-locus (rs3819024-rs2275913- rs10484879-rs7747909). Haploview analysis identified the 4-locus IL-17A haplotypes AGTG (P < 0.011), and GATG (P = 0.036) to be positively associated with CRC, after controlling key covariates. CONCLUSION: IL-17A rs10484879 SNP, and IL-17A haplotypes AGGTG and GAGTG constitute independent factors of CRC susceptibility. We propose that IL-17A may be a target for future CRC immunotherapy.

TLR2 (-196 to -174 Ins/Del) and TLR3 (1377C>T) as biomarkers for nasopharyngeal cancer in Tunisia

Background/aim: We evaluated the association of TLR2 (-196 to -174 Ins/Del) and TLR3 (1377 C>T) as potential risk factors for nasopharyngeal carcinoma (NPC) in Tunisians. Material and methods: The study subjects comprised 137 NPC patients and 164 cancer-free control subjects. TLR2 genotyping was done by PCR and TLR3 genotyping was performed by PCR-RFLP. Results: Minor allele frequency (MAF) and genotypes of TLR3 (1377 C>T) were comparable between NPC patients and controls. Significantly higher MAF and TLR2-containing Del allele genotypes of TLR2 (-196 to -174 Ins/Del) were seen in NPC patients compared to controls [OR (95% CI) = 2.10 (1.43-3.08), P < 0.001 and OR (95% CI) = 2.07 (1.27-3.37), P = 0.003]. In addition, higher increased NPC risk was associated with the TLR2-Del/Del genotype [OR (95% CI) = 2.74 (1.37-5.48), P = 0.004]. An increased frequency of the Del-T haplotype was seen in NPC cases compared to controls. Conclusion: Our results demonstrate an increased risk of NPC with the TLR2-Del/Del genotype and Del-T TLR2 and TLR3 haplotype, suggesting their potential use as biomarkers to evaluate NPC risk in Tunisians.

Role of TLRs and IL-6 in the outcome of chronic hepatitis C treatment in Tunisian population.

OBJECTIVES: TLRs are one of the most studied families of pathogen recognition receptors (PRRs) and play a pivotal role during HCV infection. The binding of ligands to TLRs on antigen presenting cells (APCs) leads to secretion of inflammatory cytokines, such as IL6, and induction of the acquired immunity response. Therefore, it has become necessarily to harness the TLRs properties' on therapeutically tools to enhance the HCV treatment response. Herein, we investigated the association between TLR3, TLR4 variants and nine IL-6 polymorphisms, and response to anti-viral treatment during HCV infection. METHODS: Study subjects comprised 120 patients infected with HCV-1b and treated with Peg-IFN/RBV. Genotyping of nine IL-6 variants were done by real -time PCR and genotyping of TLRs polymorphisms were done by RFLP-PCR. RESULTS: High frequency of TLR3 rs3775290 C/C genotype and TLR4 rs4986790 A/A genotype were noticed among patients with sustained viral response compared to Non-responder patients. The genetic association of TLR3 and TLR4 variants was evidenced by the improvement in the kinetics of viral load decline, with superiority of TLR3 compared to TLR4. Among, nine polymorphisms studied on IL-6 only rs1800796, rs2069845 and rs1880242 were associated with sustained viral response. Our study reports also that the common favourable IL-28B variant is essential for TLR-activated antiviral protection. CONCLUSION: TLR3 and TLR4 are involved in the pathogenesis of viral infections. TLR3 may be better suited than TLR4 to activate anti-viral program. Moreover, we propose that the Th2 cytokine, IL-6, constitutes a determinant of the outcome of therapy in HCV patients.

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

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

Effect of Follicle Stimulating Hormone Receptor Gene Polymorphisms in Cervical Cancer Risk.

For the first time in the word, we investigated the association between five FSHR polymorphisms with the risk of cervical cancer among Tunisians. Study subjects comprised 112 Cervical Cancer (CC) patients and 164 control women. Genotyping of FSHR rs6166, rs1007541, rs11692782, rs2055571 and rs1394205 variants was done by realtime PCR, with defined clusters. The allelic distributions of the tested FSHR SNPs were comparable between CC patients and control women. In contrast, the heterozygous genotype of rs1007541 was associated with 1.8-fold increased risk of CC. Stratification according to FIGO staging revealed that the minor allele of rs1007541 was more frequent among advanced tumor stage patients, with 11-fold increased risk of CC [P < 0.0001; OR (95 % CI) = 11.32 (7.46-17.18)]. However, no significant allelic association was revealed in the rest of analyzed FSHR SNPs. Haploview analysis showed high Linkage disequilibrium (LD) between rs2055571 and rs1394205. Haplotype analysis revealed a lack of association between cases and controls. However, analysis of CC patient subgroups demonstrated enrichment of GGTAG haplotype in early tumor stage [P = 0.025; OR (95 % CI) = 0.07 (0.01-0.70)]. The FSHR variants and haplotypes may be a genetic markers for CC susceptibility and evolution among Tunisian women.

Evaluation of Toll-Like Receptors 2/3/4/9 Gene Polymorphisms in Cervical Cancer Evolution.

Accumulative epidemiological evidence suggests that polymorphisms of Toll-like receptors signaling pathway elucidated the cellular and molecular mechanisms of human diseases whose gaining a primordial importance. The aim of our study is to identify the role of TLR 2 (-196 to -174 del), TLR 3 (1377 C>T), TLR 4 (Asp299Gly) and TLR 9 (G2848A) gene polymorphisms with the evolution of cervical cancer in Tunisian women. Blood samples were collected from histopathologically confirmed patients with cervical cancer and unrelated healthy female controls of similar ethnicity. Genotyping of the analyzed polymorphisms were done using Polymerase Chain Reaction and Restriction Fragment Length Polymorphism. For the TLR 2, Ins/Ins genotype is a protector factor [p = 0.006; OR: 0.35(0.16-0.73)] and the dominant genotype of TLR 3 increased the risk of CC in stage (III+IV); C/C versus C/T [p = 0.033; OR: 2.03(1.00-4.13)] and C/C versus C/T+T/T [p = 0.036; OR: 1.93(1.00-3.74)]. For TLR 4, the dominant genotype Asp/Asp is implicated in the occurrence of CC in stage (I+II) [p = 0.000; OR: 4.55(1.58-13.06)], [p = 0.001; OR: 3.49(1.44-8.45)] and in stage (III+IV) [p = 0.038; OR: 3.77(0.87-16.29)], [p = 0.007; OR: 5.21(1.65-16.46)] and the major allele Asp is a risk factor for the development of tumor in stage (I+II). The TLR2 Ins/Del genotype is associated with tumor evolution to stage (III+IV) [p = 0.003; OR: 3.00 (1.22-7.35)] and the genotypes Gly/Gly and Asp/Gly+Gly/Gly and Gly allele of TLR 4 are implicated in tumor evolution to the advanced stages. Further, TLR 2, TLR 3, TLR 4 and TLR 9 gene polymorphisms are implicated in the modulation of CC risk due to tobacco usage and statue of menopause among cases. Our study suggests a relationship between the incidence of the TLR2, TLR 3, TLR 4 and TLR9 mutations and the clinical progression of CC according to the FIGO classification. However, future studies with different demographic and clinical characteristics in ethnically diverse populations may provide a more comprehensive involvement of innate immunity in cervical cancer etiology in women worldwide.

IL-10 gene promoter and intron polymorphisms as genetic biomarkers of cervical cancer susceptibility among Tunisians.

OBJECTIVE: We investigated the association between polymorphisms in the promoter and intron regions of the interleukin-10 (IL-10) gene with the risk of cervical cancer (CC) in Tunisian patients and control women. METHODS: Study subjects comprised 86 CC cases and 126 control women. Genotyping of IL-10 intron (rs3024491, rs3024490) and promoter (rs1800872, rs1800871, rs1800896) variants was done by real-time PCR, with defined clusters. RESULTS: The minor allele frequencies of the five tested IL-10 SNPs were not significantly different between cervical cancer cases and control women. However, significantly higher frequencies of homozygous minor allele-carriers in cases was seen for rs3024490 (P=0.023), rs1800872 (P=0.037), and rs1800871 (P=0.028). IL-10 serum levels were significantly reduced in rs3024490 T/T vs. G/G genotype carriers, and in rs1800871 T/T than C/C genotype carriers. While carriage of rs1800872 and rs3024491 minor allele was associated with reduced IL-10 secretion, this was not statistically significant. Haploview analysis demonstrated high linkage disequilibrium (LD) among the IL10 SNPs studied, and only seven haplotypes were common, capturing 98.8% of the total possible haplotypes. Reduced frequency of haplotypes GTCCA (P<0.001) and TGATG (P<0.001) was seen in cervical cancer cases than in control women, thus conferring disease protection nature to these haplotype. This association remained significant for GTCCA (Pc=0.006) and TGATG (P=0.045) after correcting for multiple comparisons. CONCLUSION: Specific IL-10 variants (rs3024490, rs1800872, and rs1800871) and haplotype (GTCCA and TGATG) may contribute to the development of cervical cancer among Tunisian women.

Interleukin-1 Gene Cluster Polymorphisms and its Haplotypes may Predict the Risk to Develop Cervical Cancer in Tunisia.

Our study aimed to evaluate the association between IL-1α (4845 G/T), IL-1ß (-511C/T) and IL-1RN (VNTR) polymorphisms and risk of cervical cancer. This case-control study investigates three polymorphisms in 130 patients and 260 controls by PCR-restriction fragment length polymorphism (RFLP). The IL-1RN (VNTR) A1/A3 genotype appear as a cervical cancer risk factor (p = 0.048; OR = 2.92; 95 % CI = 1.00-8.74), moreover, the L/2* decreased the risk (p = 0.011; OR = 0.47; 95 % CI = 0.25-0.88) and may be a protective factor against this pathology. Stratified analysis according to the FIGO stage subgroup revealed that the IL-1ß-511 T/T genotype and T allele may be a protective factors against cervical cancer development for patients with early stage (p = 0.030; OR = 0.46; 95 % CI = 0.22-0.96) (p = 0.020; OR = 0.68; 95 % CI = 0.48-0.97). However, for the patients with advanced FIGO stage, IL-1RN-VNTR L/2* genotype appear as a protective factor for this pathology (p = 0.023; OR = 0.29; 95 % CI = 0.08-0.99). The (G-T-L) haplotype showed a significant decreased frequency in cervical cancer patients as compared to controls (p = 0.032; OR = 0.53; 95 % CI = 0.29-0.95). In contrast, the (T-T-2*) combination appear a risk factor for the development of cervical cancer (p = 0.018; OR = 1.57; 95 % CI = 1.07-2.30). Our study suggested that IL1 cluster polymorphisms and haplotypes may be a genetic risk factor for cervical cancer.

The relationship between TNF alpha gene polymorphisms (-238/-308), TNF RII VNTR (p75) and outcomes of hepatitis B virus infection in Tunisian population.

The present study was undertaken to investigate the association between Hepatitis B Virus (HBV) infection and polymorphisms of tumour necrosis factor alpha TNF-α -308 G>A, TNF-α -238 G>A and TNF RII VNTR (p75) gene promoter in a Tunisian population. Blood samples were collected from 100 Tunisian patients with HBV infection, 45 with Chronic Hepatitis (CH), 36 with Liver Cirrhosis (LC), 15 with Hepatocellular Carcinoma (HCC) and 200 healthy individuals of similar ethnicity. Genomic DNA was extracted from peripheral blood leukocytes. Genotyping of the analysed polymorphisms was performed using Amplified Refractory Mutation System-Polymerase Chain Reaction (ARMS-PCR), Restriction Fragment Length Polymorphism (RFLP) and Variable Number Tandem Repeat PCR (PCR-VNTR). The variant homozygotes -308 GG were associated with 50% decreased risk of HBV chronic infection (GG vs AA+GA; p=0.010; OR=0.50; 95%CI=0.29-0.85). However, the carriers of minor allele -308 A have higher risk (1.5 times) to develop a chronic infection than other patients (p=0.027; OR=1.46; 95%CI=1.04-2.06). The minor allele of -238 polymorphism was positively associated with virus resistance and the development of chronic infection (p=0.043; OR=1.42; 95%CI =1.01 1.99). The distribution of -308, -238 and TNF RII VNTR (p75) among the three groups differed significantly. For HCC groups, there were statistically significant differences in allele distribution in -308, -238 respectively in which A allele remains a risk factor for HBV evolution to HCC (p=0.008 and p=0.026). Haplotype analysis revealed that TNF-α (-308A; -238A) was significantly associated to HBV chronic infection and moreover to disease aggravation to HCC stage. Our findings imply that variations in the genes governing the levels of constitutive and inducible TNF-α and TNF RII might be an important risk factor, which could explain the variable outcomes of HBV infection.

Relationship of common vascular endothelial growth factor polymorphisms and haplotypes with the risk of cervical cancer in Tunisians.

OBJECTIVE: We investigated the association between common vascular endothelial growth factor (VEGF) single nucleotide polymorphisms (SNPs) and the risk of cervical cancer (CC) in Tunisian patients and control women. METHODS: Study subjects comprised 86 CC cases and 124 control women. Genotyping of VEGF rs699947, rs833061, rs1570360, rs2010963, rs25648, rs833068, rs833070, rs3025039 SNPs was done by real-time PCR. RESULTS: Higher minor allele frequencies (MAF) of rs699947 (-2578C/A) [P=0.04; OR (95% CI)=1.52 (1.02-2.29)], and rs1570360 (-1154G/A) [P=0.04; OR (95% CI)=1.58 (1.01-2.47)] were seen in CC cases compared to control women. Marked differences in the distribution of rs699947 (P=9×10(-4)) and rs1570360 (P=0.03) genotypes were seen between CC cases and control groups; the distribution of the remaining SNPs was comparable between CC cases and control women. The association of rs699947 and rs1570360 with heightened CC risk with was seen in the heterozygous, and more so in the homozygous states. Haploview analysis revealed high LD between rs699947, rs833061, rs1570360, rs2010963, rs25648, rs833068 and rs833070 but weak or no LD between rs3025039 and the other SNPs. Seven-locus (rs699947/rs833061/rs1570360/rs2010963/rs25648/rs833068/ rs833070) haploview analysis identified only CTGCCAG haplotype to be positively associated with CC [P=0.022; OR(95% CI)=1.74 (1.08-2.79)]. CONCLUSION: Specific VEGF variants (rs699947, rs1570360) and haplotype (CTGCCAG) may contribute to the development of CC among Tunisian women.