Association of HLA-G 3'UTR polymorphisms and haplotypes with colorectal cancer susceptibility and prognosis.

Human leukocyte antigen (HLA)-G has been considered as an immune modulator in several types of cancers. Its genetic polymorphisms may potentially affect the risk of developing colorectal cancer (CRC). The overall purpose of this study was to analyze the implication of HLA-G 3'untranslated region (3'UTR) polymorphisms particularly 14 pb insertion/deletion (Ins/Del; rs371194629) and + 3142C/G (rs1063320) in CRC susceptibility and progression. A comparative analysis between patients (N = 233) and controls (N = 241) demonstrated that Del allele (Odds Ratios (OR) = 1.41, 95% CI = 1.091-1.819, p = 0.008), the homozygous Del/Del genotype (OR = 1.80, 95% CI = 1.205-2.664, p = 0.003) and the codominant C/G genotype (OR = 1.59, 95% CI = 1.106-2.272, p = 0.013) were associated to CRC risk. As expected, the DelG haplotype was associated with CRC susceptibility (OR = 1.47, 95% CI = 1.068-2.012, p = 0.018). Assessment of patients' survival by Kaplan-Meier analysis indicated that the Del allele and the homozygous Del/Del genotype were associated with reduced event free survival (EFS) (Respectively, p = 0.009 and p = 0.05). Interestingly, the Del allele and the homozygous Del/Del genotype have been revealed as independent prognostic factors for poor EFS in patients with CRC. Additionally, haplotypes analysis revealed that DelG haplotype was linked with significant increase in CRC risk (log-rank; EFS: p = 0.02). Inversely, the InsC haplotype was associated with a significant reduced CRC risk (log-rank; Overall survival (OS): p < 10-6; EFS: p = 0.01). Multivariate Cox regression analysis revealed that the InsC haplotype was independently associated with significantly longer EFS (p = 0.021, HR = 0.636, 95% CI = 0.433-0.935). These findings support the implication of HLA-G polymorphisms in the CRC susceptibility suggesting HLA-G as a potent prognostic and predictive indicator for CRC. Insight into mechanisms underlying HLA-G polymorphisms could allow for the development of targeted care for CRC patients according to their genetic profile.

Prognostic significance of high circulating sHLA-G in ovarian carcinoma.

HLA-G is a non-classical major histocompatibility complex class Ib molecule. Its expression has been described in various cancer types, including ovarian cancer. HLA-G molecule has been implicated in immune escape and in progression of ovarian tumor cells. Our goal was to assess if total soluble (s)HLA-G molecules or HLA-G5 and sHLA-G1 isoforms could be considered as circulating ovarian tumor biomarkers, we measured the concentration of these molecules in ovarian carcinoma patients stratified according with their clinicopathological parameters. sHLA-G, sHLA-G1 and HLA-G5 concentrations were dosed in plasma samples by sandwich-ELISA. The sHLA-G dimerization was analyzed after immunoprecipitation and SDS-PAGE migration. Total sHLA-G and sHLA-G1 levels were significantly represented in plasma of ovarian carcinoma patients compared to healthy controls. sHLA-G1 isoform concentration was highly represented in ovarian carcinoma compared to HLA-G5 isoforms. Additionally, high sHLA-G molecules have been found in aged patients, as well as in patients with advanced stages, and those with metastatic lymph nodes and those with distant metastasis. Elsewhere, sHLA-G monomers were highly represented in ovarian carcinoma patients compared to controls. sHLA-G plasmatic protein was highly represented in ovarian carcinoma. In effect, HLA-G might be considered as a new checkpoint molecule that could be used to assess progression and recurrence of the disease, thus placing it as a potential biomarker for advanced and complicated ovarian carcinoma.

Interleukin IL-1B gene polymorphism in Tunisian patients with chronic hepatitis B infection: Association with replication levels.

Approaches based on association studies have proven useful in identifying genetic predictors for many diseases, including susceptibility to chronic hepatitis B. In this study we were interested by the IL-1B genetic variants that have been involved in the immune response and we analyzed their role in the susceptibility to develop chronic hepatitis B in the Tunisian population. IL-1B is a potent proinflammatory cytokine that plays an important role in inflammation of the liver. Polymorphic gene IL-1 (-511, +3954) was analyzed in a total of 476 individuals: 236 patients with chronic hepatitis B from different cities of Tunisia recruited in Pasteur Institute between January 2017 and December 2018 and 240 controls. Genomic DNA was obtained using the standard salting-out method and genotyping was performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism. For -511C>T polymorphism a significant association was found between patients and controls when comparing the genotypic (P = 0.007; χ2 = 9.74 and odds ratio [OR] = 0.60; confidence interval [CI] = 0.41-0.89) and allelic (P = 0.001; χ2 = 10.60) frequencies. When the viral load was taken into account a highly significant difference was found (P = 9 × 10-4 ; χ2 = 10.89). For +3954C>T polymorphism a significant association was found between patients and controls when comparing genotypic (P = 0.0058; χ2 = 7.60 and OR = 1.67; CI = 1.14-2.46) and allelic (P = 0.0029; χ2 = 8.81) frequencies. T allele can be used as a strong marker for hepatitis B virus disease for both polymorphisms.

Increased plasmatic soluble HLA-G levels in endometrial cancer.

Human Leukocyte Antigen-G (HLA-G) is known as an immune suppressive molecule; it interacts with several immune cells and inhibits their functions. HLA-G molecule is highly represented in pathological conditions including malignant transformation. To the best of our knowledge this is the first study that focuses on the expression of soluble HLA-G (sHLA-G) in endometrial cancer (EC). We aimed at exploring sHLA-G plasma levels and its prognostic value in EC. We examined total sHLA-G expression as well as the sHLA-G1 and HLA-G5 isoforms expression in plasma samples from 40 patients with EC and 45 healthy controls by a specific sandwich ELISA. Immunoprecipitation and Coomassie blue staining were performed to explore the presence of plasmatic sHLA-G monomers and dimers. sHLA-G plasma level was significantly enhanced in patients with EC compared to healthy controls (p = 0.028). Additionally, HLA-G5 molecules were highly represented than sHLA-G1 molecules in EC, at the borderline of significance (p = 0.061). Interestingly, sHLA-G has been shown to be increased in early stages (Stages I and II) as well as in high grade EC (Grade 3) that is associated with rapid spread of the disease (p = 0.057). sHLA-G positive EC plasma were majorly in monomeric form (75%). Clinically, all the HLA-G dimers were detected in early stages and in high grade of EC. Our data strengthen the implication of HLA-G molecules in EC etiology and especially in progression.

Association of HLA-G +3142 C>G polymorphism and breast cancer in Tunisian population.

HLA-G is highly expressed in cancer. Also, it is associated to its progression. Here, we explored the relationship between two HLA-G polymorphisms with breast cancer (BC) and tried to make a correlation with sHLA-G levels. We genotyped 104 patients with BC and 83 controls (CTRL) for HLA-G 14-bp insertion/deletion (Ins/Del) and HLA-G +3142 C>G polymorphisms. The mutations were identified with PCR and PCR-RFLP. The sHLA-G dosage was performed on plasma samples by a specific ELISA. A significant association with BC was found concerning the G allele in the +3142 C>G polymorphism (p = 0.0004). The G/G genotype is the protective genotype (1 % in BC patients vs. 13.1 % in CTRL, OR 0.065, 95 % CI 0.008-0.523). No statistically significant differences were observed for the 14-bp Ins/Del polymorphism between BC patients and controls frequencies. The protection by G/G genotype of +3142 C>G polymorphism is maintained in young patients (<50 years, p = 0.0006) and in early-diagnosed BC patients (<50 years, p = 0.0033). In addition, an association was found between the haplotypes inferred by both HLA-G polymorphisms and BC susceptibility. Indeed, the (DelG) haplotype is found as the protective haplotype against BC (OR 0.269, 95 % CI 0.081-0.895, p = 0.023). The ELISA dosage of sHLA-G revealed increased levels in BC compared to CTRL (p < 0.0001). We demonstrated also that sHLA-G is closely associated with advanced stages of BC without significance. sHLA-G is increased in TNM IV and SBR III subgroups. It is also enhanced in patients with a tumor size over 20 mm and in triple-negative patients. Taken together, our findings demonstrate, for the first time, the association of HLA-G +3142 C>G polymorphism with BC susceptibility in Tunisian population. Our results revealed also a potential implication of sHLA-G in advanced stages of BC.

Release of B cell-activating factor of the TNF family in bronchoalveolar lavage from Behçet's disease with pulmonary involvement.

Pulmonary artery aneurysms, arterial and venous thrombosis, pulmonary infarction, recurrent pneumonia, bronchiolitis obliterans organized pneumonia, and pleurisy are the main features of pulmonary involvement in Behçet's disease. The objective of this study was to investigate the production of B cell-activating factor of the TNF family (BAFF), an important regulator of B-cell survival and immunoglobulin class-switch recombination, in bronchoalveolar lavage (BAL) fluid from BD patients having pulmonary manifestation. Bronchoalveolar lavage (BAL) was performed in 15 BD patients with pulmonary manifestation and 18 BAL from healthy controls. Concentrations of B cell-active cytokines, including BAFF, IL-6, and IL-13, were measured by using specific ELISA and cytometric bead array assays. Levels of BAFF protein were significantly increased in BAL fluid from active BD [109 +/- 21.78 pg/mL] compared with those oh healthy controls [4.83 +/- 1.75 pg/mL; P<0.0001]. In the BAL fluid, BAFF levels were significantly correlated with absolute numbers of total cells [r = 0.823; P<0.0001], lymphocytes [r = 0.709; P<0.0001], neutrophils [r = 0.809; P<0.0001] and macrophages [r = 0.742; P<0.0001]. Normalization to albumin indicated that BAFF production occurred locally in the airways. BAFF levels were also significantly correlated with the other B cell-activating cytokines IL-6 [r = 0.882, P<0.001] and IL-13 [r = 0.659, P<0.001].The antigen-induced production of BAFF in the lung of active BD with pulmonary manifestations might contribute to immunoglobulin synthesis by B cells. The cells residing in the lung might affect each other through BAFF.

Association of vascular endothelial growth factor polymorphisms with asthma in Tunisian children.

BACKGROUND: Previous studies demonstrated that the vascular endothelial growth factor (VEGF) was being implicated in the airways inflammation and remodeling process in patients with asthma. AIMS: We explored the relationship of three polymorphisms in the VEGF gene with asthma in both case control and family studies. METHODS: We Genotyped a total of 210 children with asthma, 224 unrelated controls and 160 parents for the +936 C >T (rs3025039), -634 G > C (rs2010963) and -2549 -2567 del 18 of the VEGF promoter region. The Mutations were identified with polymerase chain reaction followed by restriction fragment length polymorphism (RFLP) analysis for the +936 C > T, and -634 G > C polymorphisms. RESULTS: Of the three polymorphisms studied, a borderline association with asthma was found for the G allele in the -634 G > C polymorphism (p = 0.059). No Statistically significant differences were observed for both +936 C > T, and -2549 -2567 del 18 polymorphisms between asthmatic patients and controls, considering either allelic or genotypic frequencies. The distribution of genotypes according to the severity status revealed a significant differences for the +936 C > T, and -2549 -2567 del 18 polymorphisms. In addition, association was found with the haplotypes inferred by the three polymorphisms and asthma susceptibility. CONCLUSION: We suggest that VEGF Gene polymorphisms can be implicated in asthma.

Association between RANTES polymorphisms and asthma severity among Tunisian children.

The chemokine known as RANTES (regulated upon activation, normal T cells expressed and secreted) is an important element for the chemotaxis at the site of allergic inflammation. Many studies have made an interesting link between RANTES polymorphisms and asthma, showing that the variant in the promoter region is associated with high risk of asthma and severe airway obstruction. We conducted a case-control and family study aiming at identifying the relationship between polymorphisms (-28 C/G and -403 G/A) and haplotypes in the RANTES gene with asthma and severity. The results of the case control study suggest an association between alleles level of -28 C/G and -403 G/A promoter polymorphism (p = 0.01) (p = 0.00175) and asthma. Univariate analysis of the RANTES polymorphisms show an increased prevalence of the AC and AG haplotypes in asthmatics (p = 0.014) and (p = 0.015) respectively. Our data suggest that -28 C/G and -403 G/A polymorphisms within the RANTES promoter region play an important role in asthma predisposition and in the severity of airway obstruction.

Increased endothelin-1 levels of BAL fluid in patients with Behçet's disease.

OBJECTIVE AND BACKGROUND: Pulmonary aneurysms and thrombosis constitute a significant cause of morbidity and mortality in Behçet's disease (BD). Various factors have been studied to explore the pathogenesis of vascular involvement in BD. As endothelin (ET) is known for its potent vasoconstrictor and proinflammatory properties, we supposed that it is involved during the inflammatory process of BD pulmonary vasculitis. METHODS: To investigate the role of ET in BD, ET-1 concentrations were measured in bronchoalveolar lavage fluid (BALF) of 18 nonsmoking BD patients with pulmonary manifestations and 12 control subjects. Immunoreactivity of ET-1 was also evaluated in alveolar macrophages (AMs) cytoplasm. RESULTS: ET-1 levels in BD-BALF were significantly higher than those of controls. ET-1 levels were correlated with the number of alveolar macrophages, but not with BAL-CD4/CD8 ratio. ET-1-immunoreactivity was found mainly in AM of BD-BAL. CONCLUSIONS: Increased ET-1 production from AM is associated with pulmonary BD manifestations.

Tumor necrosis factor gene polymorphisms in Tunisian patients with Behcet's disease.

Behcet's disease (BD) is an inflammatory disorder that is mainly characterized by recurrent oral and genital ulcers, skin lesions, and uveitis. Recent reports focused on the genetic factors of susceptibility to this disease and especially the TNF in view of the major role played by this proinflammatory cytokine in the lesional process of Behcet's disease. In this report, we investigated the possible association between Behcet's disease and the TNF-alpha gene promoter polymorphisms -1031T/C, -308A/G, and the TNF-beta polymorphism +252A/G in Tunisian population. We compared the distribution of these polymorphisms between 89 BD patients and 157 healthy controls using polymerase chain reaction restriction fragment length-polymorphism (PCR-RFLP) analysis. The frequency of the TNF-alpha -1031C allele was significantly higher in Behcet's patients than in healthy controls (p = 0.015; chi(2) = 5.84; OR = 1.65; 95% CI = 1.08-2.54), whereas the frequencies of the TNF-alpha -308G and the TNF-beta +252G alleles were similar in the two compared groups. These results suggest that the variability of the TNF-alpha -1031T/C polymorphism can be associated with the susceptibility to Behcet's disease in our study group. Therefore, the TNF molecule may have an important genetically and/or functionally implication in the pathogenesis of BD in the Tunisian population.

NKT cells in the induced sputum of severe asthmatics.

To determine whether there was a specific inflammatory process in severe asthmatics, the phenotypic characteristics of induced sputum immune cells were analysed among patients with severe asthma. Twenty-two induced sputa (10 severe asthmatics) were studied. Flow cytometric analysis was performed using immune cells of the sputum and monoclonal antibodies to CD3, CD4, CD8, CD56, CD25, and TCRgammadelta. The number of NKT (CD3(+) CD56(+)) cells was significantly higher in the sputum of severe asthmatics compared with mild asthmatic and healthy control groups (P < .05). CD8(+)CD56(+) cells were the predominant subtype of the increased NKT cells in severe asthmatics. CD3(+)CD56(+)Valpha24(+), TCRgammadelta(+) CD56(+), and CD4(+)CD25(+) T cells were significantly increased in severe asthmatic patients. These results suggest that the immunopathogenesis of severe asthmatics vary between severe and mild asthmatics, and that CD8(+)CD56(+) NKT cells may play an important role in the immunopathogenesis of severe asthma.