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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 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.

Pregnancy is associated with increased levels of soluble (s) human leukocyte antigen (HLA)-G molecules, while during abortion these molecules are decreased. To date, little is known about the role of sHLA-G isoforms during abortion. In this study, we investigated the levels of total sHLA-G and its isoforms: HLA-G1 (membrane shedded isoform) and alternative spliced HLA-G5 in plasma samples obtained from 55 women who had experienced spontaneous abortion, 108 pregnant healthy women and 56 non pregnant healthy women. We found that pregnant women exhibited higher amounts of sHLA-G compared to either non pregnant women or women with abortion. Among women who had experienced spontaneous abortion, women with recurrent abortions (RSA) had lower sHLA-G than women with only one abortion. In particular, RSA women were characterized by the absence of sHLA-G1 isoform, suggesting a possible implication in abortion event.

Aims Several evidences suggest the association between the evolution of coronary artery disease (CAD) and the development of coronary syndrome that is often associated with disrupted plaque and partial or complete thrombosis of the related artery. Because of the inflammatory nature of CAD, we investigated the human leukocyte antigen (HLA)-G, HLA-E, and HLA-F genetic polymorphisms within CAD patients and evaluated their potential association with this disease in Tunisian population. Methods Different polymorphisms in HLA-G (14-bp Insertion/Deletion, +3142C/G), HLA-E (HLA-E*01:01/01:03 A/G), HLA-F (HLA-F*01:02 T/C, 01:03 C/T, 01:04 A/C) genes were typed using different laboratory techniques in a cohort of 89 CAD patients and 84 controls. Results A significant association was reported between the HLA-G +3142 G allele (OR = 1.64, 95% CI = 1.05–2.56, p = 0.02) and increased risk of CAD. No association was found for the other studied polymorphisms. When we considered the haplotypes, we found TDELCA and TDELGG haplotypes associated to CAD with p = 0.008 and p = 0.030, respectively, suggesting the potential interaction between HLA-G and HLA-E genes. Conclusions Our findings indicated that the HLA-G +3142C/G polymorphism and TDELCA and TDELGG haplotypes can harbour a reliable diagnosis value for the risk of CAD development suggesting that HLA-G, -E and -F molecules might be involved in the pathogenesis of the disease. However, further studies are necessary to confirm our results.

Chronic hepatitis B virus (HBV) infection occurs in association to a deregulation of immune system. Human leukocyte antigen E (HLA-E) is an immune-tolerant nonclassical HLA class I molecule that could be involved in HBV progression. To measure soluble (s) HLA-E in patients with chronic HBV hepatitis (CHB). We tested the potential association of HLA-E*01:01/01:03 A > G gene polymorphism to CHB. Our cohort consisted of 93 Tunisian CHB patients (stratified in CHB with high HBV DNA levels and CHB with low HBV DNA levels) and 245 healthy donors. Plasma sHLA-E was determined using enzyme-linked immunosorbent assay (ELISA). Genotyping was performed using polymerase chain reaction sequence-specific primer. No association between HLA-E*01:01/01:03 A > G polymorphism and HBV DNA levels in CHB patients was found. G/G genotype is less frequent in CHB patients without significance. sHLA-E is significantly enhanced in CHB patients compared with healthy controls (P = 0.0017). Stratification according to HBV DNA levels showed that CHB patients with low HBV DNA levels have higher sHLA-E levels compared with CHB patients with high HBV DNA levels. CHB patients with G/G genotype have enhanced sHLA-E levels compared with other genotypes (P = 0.037). This significant difference is maintained only for CHB women concerning G/G genotypes (P = 0.042). Finally, we reported enhanced sHLA-E in CHB patients with advanced stages of fibrosis (P = 0.032). We demonstrate, for the first time, the association of sHLA-E to CHB. Owing to the positive correlation of HLA-E*01:01/01:03 A > G polymorphism and the association of sHLA-E to advanced fibrosis stages, HLA-E could be a powerful predictor for CHB progression. Further investigations will be required to substantiate HLA-E role as a putative clinical biomarker of CHB.

Human leukocyte antigen (HLA)-F has been involved in immune regulation of infectious diseases. However, the role of HLA-F polymorphisms in hepatitis B infection outcomes remains unclear. Here, we aimed to determine HLA-F polymorphism implication in chronic HBV. Genotype analysis was performed for three single nucleotide polymorphisms (SNPs) of HLA-F and one SNP of HLA-E using PCR-SSP, in 252 Tunisian patients with chronic HBV infection stratified according to their HBV DNA levels (140 patients with low HBV DNA levels

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.

Background The human leukocyte antigen (HLA)-G and HLA-E, non classical HLA class I molecules, have been highly implicated in immune tolerance. HLA-G and HLA-E molecules were proposed as putative markers of several advanced cancers. As a step towards a better understanding of ovarian carcinoma, we evaluated the expression of both HLA-G and HLA-E molecules and explored their prognostic implication. Methods HLA-G and HLA-E expression were studied by immunohistochemistry on ovarian carcinoma tissues. This expression was semi-quantitatively scored into four expression groups and correlated to clinicopathological parameters and patients’ survival. Results HLA-G and HLA-E have been found to be highly expressed in ovarian carcinoma tissues (Respectively, 72.4% and 96.8%). They are frequently co-expressed. Univariate and multivariate analysis revealed that a positive HLA-G expression status in tumor tissue is a promising candidate parameter to predict disease recurrence in addition to the disease status in Tunisian patients with ovarian carcinoma. Moreover, the elevated HLA-E expression was associated with serous ovarian carcinoma subtype as well as with advanced stages of ovarian carcinoma. Conclusion HLA-G and HLA-E are highly represented in ovarian carcinoma suggesting a potential association with progressive disease mechanism. HLA-G and HLA-E molecules might be new candidates’ markers for ovarian carcinoma progression.

Hepatitis B virus (HBV) infection is a global health problem. The mechanisms of immune tolerance in HBV infection are still unclear. The host immune response plays a critical role in determining the outcome of HBV infection. Human leucocyte antigen-G (HLA-G) is involved in immunotolerogenic process and infectious diseases. This study aimed to explore the implication of soluble HLA-G (sHLA-G) and its isoforms in HBV infection. Total sHLA-G (including shedding HLA-G1 and HLA-G5) was analysed by ELISA in 95 chronic HBV patients, 83 spontaneously resolvers and 100 healthy controls (HC). To explore the presence of sHLA-G dimers, we performed an immunoprecipitation and a Western blot analysis on positive samples for sHLA-G in ELISA. The serum levels of sHLA-G were significantly increased in patients with chronic HBV patients compared to spontaneously resolvers and HC (P

International audience; 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.

The aim of this study was to evaluate the association between the HLA-G 14-bp deletion/insertion (Del/Ins) polymorphism and soluble (s) HLA-G production in patients with Crohn’s disease (CD). We analyzed also the sHLA-G molecules by ELISA and western blot in plasma samples. Among unselected patients, the 14-bp Del/Ins polymorphism was not significantly associated with increased CD risk neither for alleles (P = 0.371) nor for genotypes (P = 0.625). However, a significant association was reported between the 14-bp Del/Ins polymorphism and CD, in particular in young-onset CD patients for alleles [P = 0.020, odds ratio (OR) = 2.438, 95% confidence interval (CI): 1.13–5.25] but not with adult-onset CD patients. A significant association was reported concerning the genotype Ins/Ins for young-onset CD patients (P = 0.029, OR = 3.257, 95% CI: 1.08–9.77). We observed also a significant increase in sHLA-G measured by ELISA in CD patients compared to controls (P = 0.002). The 14-bp Del/Del and 14-bp Del/Ins genotypes are the high HLA-G producers. Among sHLA-Gpositive patients, 43% of subjects present dimers of HLA-G. The presence of dimers seems to be related to the advanced stages of the disease. The 14-bp Del/Ins polymorphism is associated with an increased risk of CD particularly in young-onset CD patients and controls sHLA-G plasma levels. Dimers of sHLA-G are frequent in advanced disease stages. The above findings indicate that the genetic 14-bp Del/Ins polymorphism in exon 8 of the HLA-G gene is associated with the risk of CD and suggest a role for sHLA-G as a prognostic marker for progressive disease.

Identification of an HLA-G 14-bp Insertion/Deletion (Ins/Del) polymorphism at the 3' untranslated region of HLA-G revealed its importance in HLA-G mRNA stability and HLA-G protein level variation. We evaluated the association between the HLA-G 14-bp Ins/Del polymorphism in patients with chronic Hepatitis B virus (HBV) infection in a case-control study. Genomic DNA was extracted from 263 patients with chronic HBV hepatitis and 246 control subjects and was examined for the HLA-G 14-bp Ins/Del polymorphism by PCR. The polymorphic variants were genotyped in chronic HBV seropositive cases stratified according to HBV DNA levels, fibrosis stages and in a control population. There was no statistical significant association between the 14-bp Ins/Del polymorphism and increased susceptibility to HBV infection neither for alleles (P = 0.09) nor for genotypes (P = 0.18). The stratification of HBV patients based on HBV DNA levels revealed an association between the 14-bp Ins/Del polymorphism and an enhanced HBV activity with high HBV DNA levels. In particular, the Ins allele was significantly associated with high HBV DNA levels (P = 0.0024, OR = 1.71, 95% CI 1.2-2.4). The genotype Ins/Ins was associated with a 2.5-fold (95% CI, 1.29-4.88) increased risk of susceptibility to high HBV replication compared with the Del/Del and Ins/Del genotypes. This susceptibility is linked to the presence of two Ins alleles. No association was observed between the 14-bp Ins/Del polymorphism and fibrosis stage of HBV infection. We observed an association between the 14-bp Ins/Del polymorphism and high HBV replication characterized by high HBV DNA levels in chronic HBV patients. These results suggest a potential prognostic value for disease outcome evaluation.