Association between genetic variants of TLR2, TLR4, TLR9 and schizophrenia.

BACKGROUND AND STUDY AIM: Schizophrenia (SZ) is a multifactorial disorder involving complex interactions between genetic and environmental factors, where immune dysfunction plays a key etiopathogenic role. In order to explore the control of innate immune responses in SZ, we aimed to investigate the potential association between twelve TLR2, TLR4 and TLR9 variants (TLR2: rs4696480T>A, rs3804099T>C, rs3804100T>C; TLR4: rs1927914G>A, rs10759932T>C, rs4986790A>G, rs4986791T>C, rs11536889G>C, rs11536891T>C; TLR9: rs187084A>G, rs352139T>C and rs352140C>T) and SZ susceptibility in a Tunisian population. PATIENTS AND METHODS: This study included 150 patients and 201 healthy controls with no history of psychiatric illness. Genotyping was done using a TaqMan SNP genotyping assay. We also assessed a haplotype analysis for TLR2, TLR4 and TLR9 variants with SZ using Haploview 4.2 Software. RESULTS: We found that the AA genotype of the TLR2 rs4696480T>A variant was significantly associated with an increased risk of SZ (46% vs. 31%, P=4.7×10-3, OR=1.87 and 95% CI [1.18-2.97]). The frequency of the TA genotype was significantly higher in the control group than in SZ patients (27% vs. 43%, P=2.1×10-3) and may be associated with protection against SZ (OR=0.49 and 95% CI [0.30-0.80]). Whereas, the TLR9 rs187084-GG genotype was higher in the control group compared to patients (16% vs. 5%, P=1.6×10-3) and would present protection against SZ (OR=0.28, CI=[0.10-0.68]). The ACT haplotype of the TLR2 and the ACC haplotype of the TLR9 gene were identified as a risk haplotypes for SZ (P=0.04, OR=9.30, 95% CI=[1.11-77.71]; P=3×10-4, OR=6.05, 95% CI=[2.29-15.98], respectively). CONCLUSION: The results indicate that TLR2 and TLR9 genetic diversity may play a role in genetic vulnerability to SZ. However, including more patients and evaluation of TLR2 and TLR9 expression are recommended.

High-Sensitive c-Reactive Protein Levels in Euthymic Bipolar Patients: Case-Control Study.

Bipolar disorder is a chronic, disabling disease that is characterized by the recurrence of thymic episodes. The role of the immune-inflammatory system in the etiopathogenesis of this affection arouses the interest of research. The aim of this work was to determine the plasma levels of the high sensitivity C reactive protein (hs-CRP) in patients with bipolar disorder in remission phase by comparing them to a control group.A case-control cross-sectional study was conducted from 56 subjects with bipolar disorder in clinical remission, and 56 volunteers and healthy control subjects.Mean plasma hs-CRP was significantly higher in patients with bipolar disorder than control subjects. In bipolar patients, a hs-CRP elevation was significantly associated with the disease severity item mean score.Through this study, bipolar disorder appears to be associated with a state of chronic inflammation. This should lead to randomized controlled trials evaluating the value of anti-inflammatory drugs in the management of bipolar disorder.

The Impact of HLA-G 3'UTR Polymorphisms in Breast Cancer in a Tunisian Population.

Human leukocyte antigens G and E (HLA-G and HLA-E) are nonclassical major histocompatibility complex (MHC) class I molecules. These molecules play an important role in immune surveillance by inhibiting natural killer and cytotoxic T cells responsible for immune escape. The expression of HLA-G and HLA-E has been associated with several diseases including tumor. The main objective of the study is to evaluate the impact of three HLA-G 3'UTR potential polymorphisms: +3187 A > G (rs9380142), +3142 G > C (rs1063320), +2960 14-base pair (bp) Insertion/Deletion (Ins/Del) (rs66554220), and the HLA-E*01:01/01:03 A > G (rs1264457) polymorphism in Tunisian breast cancer population. A total of 355 patients and 381 controls were genotyping for HLA-G and HLA-E polymorphisms using a Taq Man assay. +3142 C allele and +3142 C/C genotype were significantly associated with increased risk of breast cancer (p = 0.00002; OR = 1.58; 95% CI = 27-1.97) (49% versus 35%; p = 0.0001; OR = 1.79; 95% CI = 1.32-2.44). In addition, Del allele and the homozygous state for Del/Del genotype confer a risk for breast cancer (52% versus 45%, p = 0.006; OR = 1.33, 95% CI = 1.08-1.64) (28% versus 22%, p = 0.039; OR = 1.43, 95% CI = 0.90-2.25). However, no statistical significant differences were reported for HLA-G + 3187 A > G and HLA-E variations and breast cancer in a Tunisian population. The found results indicate that HLA-G may play an important role in the breast cancer.

Role of p53 Codon72 SNP in breast cancer risk and anthracycline resistance.

BACKGROUND/AIM: We undertook a case-control and a case-case study to examine the possible association of p53 codon72 polymorphism with the breast cancer risk and resistance to anthracycline-based chemotherapy. PATIENTS AND METHODS: Case-control study: This study enrolled 175 patients with breast cancer treated at the Salah Aziez Institute and 159 healthy Tunisian women (matched for age, ethnicity and origin), used as a control, with no clinical evidence of any neoplastic disorder. Case-Case study: 400 breast cancer patients, with invasive ductal carcinoma (IDC) treated with anthracycline based-chemotherapy. Genomic DNA was isolated from whole-blood leucocytes using the phenol-chloroform method. Anthracycline response was scored according to the World Health Organization (WHO) criteria. P53 codon72 polymorphism was genotyped using real-time polymerase chain reaction (RT-PCR) with the TaqMan method. Data were statistically analyzed using the Chi-square test. RESULTS: Clinical data revealed that among the 400 patients, one quarter was resistant to chemotherapy treatment. Genetic data revealed that the p53 Arg72Pro genotype was found to be greatly associated with breast cancer risk (p<0.001), as well as tumor site (p=0.046). However, resistance to anthracycline-based chemotherapy does not seem to be correlated with p53 codon72 polymorphism in our population. Also, the distribution of tumor size, lymph node involvement and tumor grade was not significantly different among the polymorphic variants. CONCLUSION: We conclude that p53 codon72 polymorphism is involved in susceptibility to developing breast cancer. It may be a factor of progression when breast sites are taken into account. However, there is no evidence indicating that Arg72Pro SNP may influence response to anthracycline-based chemotherapy.

[Immunogenetics of nasopharyngeal carcinoma]. / Immunogénétique du cancer du nasopharynx.

Nasopharyngeal carcinoma (NPC) is a complex multifactorial disorder involving both genetic and environmental factors. Genetic predisposition linked to the immune system has been associated with various tumors. This involves genetic diversity of the genes encoding the molecules of the immune response such as inflammation and anti-tumor surveillance. In this work, we examined the impact of the immunogenetic diversity on the risk of the NPC in different populations studied. These data show that the interindividual variability of the genetic regulation of immune processes increases the risk of NPC in individuals previously predisposed due to other risk factors (genetic / environmental). This synthesis, in addition to the predictive aspects, could provide innovative research for the development of new therapeutic approaches.

Impact of lifestyle factors and nutrients intake on occurrence of gastrointestinal cancer in Tunisian population.

This study aims to show the relationship between lifestyle and risk of colorectal and gastric cancers in Tunisian population. The food frequency survey method was used to obtain information about the dietary intake and way of life. Nutrients intake was calculated according to the food composition database. According to our results, the consumption of vegetables, fruits, fish, as well as coffee seems to be protective against digestive cancer, while the consumption of citrus and olive oil is protective against gastric cancer. Tobacco, alcohol, and tea represent a risk against gastrointestinal cancer. Highly educated people are more conscious of the crucial role of prevention. In addition, nutrients were significantly associated with colorectal and gastric cancer. The findings suggest that lifestyle is associated with a risk of gastrointestinal cancer. Moreover, higher intake of nutrients from foods was observed more in cases with colorectal and gastric cancer than controls.

Consistent high concentration of the viral microRNA BART17 in plasma samples from nasopharyngeal carcinoma patients--evidence of non-exosomal transport.

BACKGROUND: Because latent Epstein Barr (EBV)-infection is a specific characteristic of malignant nasopharyngeal carcinoma (NPC), various molecules of viral origin are obvious candidate biomarkers in this disease. In a previous study, we could show in a few clinical samples that it was possible to detect a category of EBV microRNAs called miR-BARTs in the plasma of at least a fraction of NPC patients. The first aim of the present study was to investigate the status of circulating miR-BART17-5p (one of the miR-BARTs hereafter called miR-BART17) and EBV DNA in a larger series of NPC plasma samples. The second aim was to determine whether or not circulating miR-BART17 was carried by plasma exosomes. PATIENTS AND METHODS: Plasma samples were collected from 26 NPC patients and 10 control donors, including 9 patients with non-NPC Head and Neck squamous cell carcinoma and one healthy EBV carrier. Concentrations of miR-BART17 and two cellular microRNAs (hsa-miR-16 and -146a) were assessed by real-time quantitative PCR with spike-in normalization and absolute quantification. In addition, for 2 patients, exosome distributions of miR-BART17 and miR-16 were investigated following plasma lipoprotein fractionation by isopycnic density gradient ultrcentrifugation. RESULTS: The miR-BART17 was significantly more abundant in plasma samples from NPC patients compared to non-NPC donors. Above a threshold of 506 copies/mL, detection of miR-BART17 was highly specific for NPC patients (ROC curve analysis: AUC=0.87 with true positive rate = 0.77, false positive rate = 0.10). In this relatively small series, the concentration of plasma miR-BART17 and the plasma EBV DNA load were not correlated. When plasma samples were fractionated, miR-BART17 co-purified with a protein-rich fraction but not with exosomes. CONCLUSIONS: Detection of high concentrations of plasma miR-BART17 is consistent in NPC patients. This parameter is, at least in part, independent of the viral DNA load. Circulating miR-BART17 does not co-purify with exosomes.