IL-10 and IL-28B gene variants as predictors of sustained response to peginterferon and ribavirin therapy in chronic HCV infection.

OBJECTIVES: Interleukin-10 (IL-10) plays an important role in the immunity to hepatitis C virus (HCV). Insofar as IL-10 variants are associated with altered levels of IL-10, previous studies that examined the association of IL-10 polymorphisms with the susceptibility to and progression of chronic HCV, and response to anti-viral treatment were inconsistent. We investigated the association between common IL-10 variants in the intron and the promotor region with HCV and associated features. METHODS: Study subjects comprised 120 patients infected with HCV-1b, and treated with Peg-IFN/RBV. Genotyping of six IL-10 promoter variants in the intron region (rs1878672, rs1554286, rs1518111) and promotor region (rs1800872, rs1800871, rs1800896) were done by real-time PCR. RESULTS: Compared to G/G, carriage of IL-10 rs1800896 (-1082A/G) A/A genotype was more frequent in patients with sustained virological response (SVR). The decline in viral load over the first 12weeks of treatment was more pronounced in rs1800896 A/A genotype carriers, compared to G/G genotype carriers, and was irrespective of the treatment dosage. Carriage of rs1800896 A/A genotype was positively associated with improvement in viral load decline, which was simultaneous, with and without carriage of the common favourable IL-28B variant. Carriage of both IL-10 rs1800896 G/G and IL-28B non-favourable genotype was associated with twice the risk of getting slow decline of viral load during treatment. Haploview analysis identified ACGCTA and CCGCTG haplotypes to be linked with excellent PegIFN/RBV cure rate, and complete HCV eradication. On the other hand, ACGCTG and CCGCTA haplotypes were associated with resistance to PegIFN/RBV treatment. CONCLUSION: IL-10 rs1800896 variant markedly influences the clinical outcome of HCV infection, and is a determinant of the response to HCV treatment.

Single nucleotide polymorphism of transforming growth factor-ß1 and interleukin-6 as risk factors for ovarian cancer.

INTRODUCTION: We investigated the association between common variants in TGF-ß1, IL-6 and the risk of ovarian cancer (OC) in Tunisian patients and control women. MATERIAL METHODS AND RESULTS: Study subjects comprised 71 OC cases and 74 control women. Genotyping of TGF-ß1 and IL-6 SNPs was done by real-time PCR. No differences were noted in the minor allele frequencies of the three TGF-ß1 SNPs between OC patients and controls. However, marked differences in the distribution of TGF-ß1 rs1800469 genotypes were seen between OC cases and controls (p < 0.001), with TGF-ß1 rs1800469 heterozygous (C/T) genotype being negatively associated with OC (OR [95% CI] = 0.24 [0.15-0.58]). The allelic and genotypic distributions at IL-6 polymorphisms showed a positive association between minor allele (G) at IL-6 rs1880242 variant (p = 0.0275; R [95% CI] = 1.88 [1.03-3.46]) and the occurrence of OC. In fact, the presence of T allele [G/T + T/T] decrease the risk of OC (p = 0.021; OR [95% CI] = 0.38 [0.17-0.88]). In addition, the Haploview analysis demonstrated high linkage disequilibrium (LD) between IL-6 SNPs and eight-locus haplotype analysis identified that GGAGGGGA and GGAGGGTA haplotypes are positively associated with OC risk. A negative association was shown between IL-6 haplotype (TGGGCCTA) and OC occurrence. CONCLUSIONS: Our results suggest that TGF-ß1 rs1800469, IL-6 rs1880242 variants and IL-6 haplotype (TGGGCCTA) have protective roles of OC risk. IL-6 haplotypes (GGAGGGGA and GGAGGGTA) increase OC susceptibility among Tunisian women.

Common variants in IL-1RN, IL-1ß and TNF-α and the risk of ovarian cancer: a case control study.

AIM OF THE STUDY: Several studies implicated altered inflammatory response in the susceptibility to ovarian cancer, and polymorphisms in inflammatory cytokines were shown to play an important role in the development of malignancies, including ovarian cancer (OC). Here we investigated the relationship between polymorphisms in IL-1ß (-511C>T), IL-1RN VNTR, TNF-α (-308G>A), and TNF RII (-322 VNTR) and OC risk in Tunisian women. METHODS AND RESULTS: Study subjects comprised 62 OC patients and 126 healthy women. Genotyping was done from genomic DNA obtained from blood simple by PCR. Positive association between IL-1RN (-VNTR) A1 allele (p = 0.0069; OR = 2.04; 95% CI:1.17-3.58) and OC risk, while negative association was seen with the A3 allele (P = 0.0034; OR = 0.09; 95% CI: 0.00-0.64), suggesting a protective role by the A3 allele. For IL-1ß (-511C>T), homozygous C/C genotype was associated with significantly increased risk of OC (p = 0.0002; OR = 4.14; 95% CI: 1.77-9.76), while heterozygote C/T genotype was linked with reduced risk of OC (p = 0.0033; OR = 0.40; 95% CI: 0.20-0.78). Furthermore, TNF-α -308A allele was significantly associated with heightened risk of OC (p = 0.016; OR = 1.70; 95% CI: 1.08-2.69), and homozygote G/G genotype was associated with decreased risk of OC (p = 0.0018; OR = 0.25; 95% CI: 0.09-0.66). In contrast, TNFRII (-322 VNTR) polymorphism was not associated with altered OC risk in the studied group. CONCLUSIONS: The significant association between IL-1RN VNTR, IL1-ß (-511), TNF-α (-308) and OC susceptibility in Tunisian women confirms a role for altered inflammatory response in ovarian cancer pathogenesis.

Genetic variants in IL-6 and IL-10 genes and susceptibility to hepatocellular carcinoma in HCV infected patients.

BACKGROUND: Hepatitis C virus (HCV) infection is the major cause of hepatocellular carcinoma (HCC), a common primary liver malignancy, and the third leading cause of cancer-related death. The HCC risk increases with the severity of liver inflammation, and the clinical course of HCV infection depends on a balance between pro- and anti-inflammatory cytokines. The former includes interleukin (IL)-6, while the latter includes IL-10. However, the exact pathogenic mechanisms underlying IL-6 and IL-10 effects remain unclear. METHODS: The present study evaluated 174 chronic HCV Tunisian patients. Polymorphisms of IL-6 (rs1880242, rs1474847, rs2069840, rs1800797, rs1800796, rs2069845, rs2069827, rs1474348, rs1800795), and IL-10 (rs1800896, rs1800871, rs1800872, rs1554286, rs1878672, rs1518111) were determined by real-time PCR. RESULTS: Notable differences between chronic HCV-infected patients and HCC patients were observed for the three IL-10 SNPs; rs1800871 (-819T/C), rs1800872 (-592A/C), and rs1878672. Carriage of IL-6 rs1800796 G/G genotype, IL-6 rs1474358 C-allele, and IL-6 rs1800797 A-allele was more frequent in chronic HCV-infected patients than in HCC patients. On the other hand, IL-6 rs1474358 GG genotype had a favourable factor for HCC establishment. CONCLUSION: IL-10 and IL-6 SNPs markedly influence the clinical outcomes of HCV infection. These SNPs could be used as biomarkers for early detection and molecular therapy for preventing HCC, and prognostic factors for predicting the clinical outcomes of HCC.

Are HLA DQB1 alleles correlated with breast cancer histopronostic parameters in Tunisia?

BACKGROUND: Tumor cells express surface structures different from normal cells. These structures may be recognized by the immune system, which ensure anti-tumoral surveillance. Antigenic presentation requires HLA molecules role. Since, these molecules are encoded by a high polymorphic system, immune response can be modulated according to HLA genotype. So, HLA polymorphism could be correlated with tumor escape from anti-tumor immunosurveillance. AIM: We have aimed to search for possible associations between HLA DQB1 alleles and the histoprognostical parameters in breast cancer in the Tunisian population. METHODS: DQB1 alleles were determined by PCR-SSO molecular typing in 100 healthy matched and unrelated Tunisian female and 87 Tunisian women with breast cancer. RESULTS: Allelic distribution between the two studied groups showed no significant associations between this locus and the occurrence, the EE grade and the lymph node invasion of breast cancer in the Tunisian population. CONCLUSION: This result may be explained by the fact that cancer is a multifactoral disease due to several interacting factors that might change from one population to another.

Islands inside an island: reproductive isolates on Jerba island.

Jerba Island, located in South Eastern Tunisia, is inhabited by four ethnic groups: Berbers, Arabs, sub-Saharans, and Jews. All live in distinct areas, although the Arabs are also distributed all over the island. The first Arab settlement was founded in the 7th century A.D., so co-existence with Berbers has lasted for more than a millennium. Religious and cultural differences have represented an obstacle to the intermixing of these groups, and among both Arabs and Berbers marriages usually occur between members from the same extended family. Using new mtDNA data and previously described Y-chromosome STR-defined haplotypes, we tested whether this reported inbreeding would be reflected in the differentiation between Berber and Arab communities. Concerning mtDNA, the Berber group presented a greater Eurasian contribution (87%), and, surprisingly, no U6 haplotypes were found; in contrast, the Arabs showed a larger contribution of sub-Saharan lineages (24%) and the U6 haplogroup amounted to 10%. Another source of evidence for the reproductive isolation of the two groups was revealed through the analysis of haplotype matching (both mtDNA and Y-chromosome), showing that matching probabilities between them is of the same order of magnitude of that observed when contrasting samples from different European countries.

Y-chromosomal STR haplotypes in three ethnic groups and one cosmopolitan population from Tunisia.

The 11 Y-chromosomal short tandem repeats (STRs) included in the Promega Corporation PowerPlex Y System (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438 and DYS439) were typed in three ethnic groups ("Andalusians", Berber and Arab) and one cosmopolitan population (Tunis) from Tunisia, summing up 247 individuals, and 139 different haplotypes. Focusing the analysis on the seven Y-STRs of the YHRD Minimal Haplotype Core (DYS385 excepted), "Andalusians" showed no differences from the Cosmopolitan and the Arab samples previously published (our Arab sample presented an extremely low haplotype diversity), but were different from the Berbers. The Berbers from Tunisia were not different from those from Morocco.

Distribution of Y chromosome lineages in Jerba island population.

We have analysed Y chromosome polymorphism on six STR markers (DYS19, DYS389I, DYS390, DYS391, DYS392, and DYS393) and eight classical UEP markers (SRY10831a, YAP, SRY4064, M2, 92R7, M9, SRY2627 and 12f2) in three distinct ethnical, linguistic and cultural groups of Jerba island (Berbers, Arabs and a Jerban group of Sub-Saharan origin). Fst genetic distance and principal co-ordinate analysis based on STR haplotype frequencies, showed a genetic differentiation between the three Jerban groups and a genetic relationship between Jerban Berbers and Mozabites (a well defined Berber group in Algeria). Compound use of UEP and STR markers have increased discriminatory capacity. The detection of the most common haplotype (H9) in both Berbers and Mozabites may be useful in forensic special cases.