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1.
Nat Commun ; 13(1): 449, 2022 02 01.
Article in English | MEDLINE | ID: mdl-35105882

ABSTRACT

Genetic and non-genetic factors contribute to breast cancer development. An epigenome-based signature capturing these components in easily accessible samples could identify women at risk. Here, we analyse the DNA methylome in 2,818 cervical, 357 and 227 matched buccal and blood samples respectively, and 42 breast tissue samples from women with and without breast cancer. Utilising cervical liquid-based cytology samples, we develop the DNA methylation-based Women's risk IDentification for Breast Cancer index (WID-BC-index) that identifies women with breast cancer with an AUROC (Area Under the Receiver Operator Characteristic) of 0.84 (95% CI: 0.80-0.88) and 0.81 (95% CI: 0.76-0.86) in internal and external validation sets, respectively. CpGs at progesterone receptor binding sites hypomethylated in normal breast tissue of women with breast cancer or in BRCA mutation carriers are also hypomethylated in cervical samples of women with poor prognostic breast cancer. Our data indicate that a systemic epigenetic programming defect is highly prevalent in women who develop breast cancer. Further studies validating the WID-BC-index may enable clinical implementation for monitoring breast cancer risk.


Subject(s)
Breast Neoplasms/genetics , DNA Methylation , Epigenomics/methods , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Breast/cytology , Breast/metabolism , Breast Neoplasms/metabolism , Cervix Uteri/cytology , Cervix Uteri/metabolism , CpG Islands , Epigenome , Epithelial Cells/metabolism , Female , Humans , Mutation , Prognosis , ROC Curve
2.
Lancet Oncol ; 20(8): 1171-1182, 2019 08.
Article in English | MEDLINE | ID: mdl-31300207

ABSTRACT

BACKGROUND: Various factors-including age, family history, inflammation, reproductive factors, and tubal ligation-modulate the risk of ovarian cancer. In this study, our aim was to establish whether women with, or at risk of developing, ovarian cancer have an imbalanced cervicovaginal microbiome. METHODS: We did a case-control study in two sets of women aged 18-87 years in the Czech Republic, Germany, Italy, Norway, and the UK. The ovarian cancer set comprised women with epithelial ovarian cancer and controls (both healthy controls and those diagnosed with benign gynaecological conditions). The BRCA set comprised women with a BRCA1 mutation but without ovarian cancer and controls who were wild type for BRCA1 and BRCA2 (both healthy controls and those with benign gynaecological conditions). Cervicovaginal samples were gathered from all participants with the ThinPrep system and then underwent 16S rRNA gene sequencing. For each sample, we calculated the proportion of lactobacilli species (ie, Lactobacillus crispatus, Lactobacillus iners, Lactobacillus gasseri, and Lactobacillus jensenii), which are essential for the generation of a protective low vaginal pH, in the cervicovaginal microbiota. We grouped samples into those in which lactobacilli accounted for at least 50% of the species present (community type L) and those in which lactobacilli accounted for less than 50% of the species present (community type O). We assessed the adjusted association between BRCA1 status and ovarian cancer status and cervicovaginal microbiota community type, using a logistic regression model with a bias reduction method. FINDINGS: Participants were recruited between Jan 2, 2016, and July 21, 2018. The ovarian cancer set (n=360) comprised 176 women with epithelial ovarian cancer, 115 healthy controls and 69 controls with benign gynaecological conditions. The BRCA set (n=220) included 109 women with BRCA1 mutations, 97 healthy controls wild type for BRCA1 and BRCA2 and 14 controls with a benign gynaecological condition wild type for BRCA1 and BRCA2. On the basis of two-dimensional density plots, receiver-operating characteristic curve analysis, and age thresholds used previously, we divided the cohort into those younger than 50 years and those aged 50 years or older. In the ovarian cancer set, women aged 50 years or older had a higher prevalence of community type O microbiota (81 [61%] of 133 ovarian cancer cases and 84 [59%] of 142 healthy controls) than those younger than 50 years (23 [53%] of 43 cases and 12 [29%] of 42 controls). In the ovarian cancer set, women younger than 50 years with ovarian cancer had a significantly higher prevalence of community type O microbiota than did age-matched controls under a logistic regression model with bias correction (odds ratio [OR] 2·80 [95% CI 1·17-6·94]; p=0·020). In the BRCA set, women with BRCA1 mutations younger than 50 years were also more likely to have community type O microbiota than age-matched controls (OR 2·79 [95% CI 1·25-6·68]; p=0·012), after adjustment for pregnancy (ever). This risk was increased further if more than one first-degree family member was affected by any cancer (OR 5·26 [95% CI 1·83-15·30]; p=0·0022). In both sets, we noted that the younger the participants, the stronger the association between community type O microbiota and ovarian cancer or BRCA1 mutation status (eg, OR for community type O for cases aged <40 years in the ovarian cancer set 7·00 [95% CI 1·27-51·44], p=0·025; OR for community type O for BRCA1 mutation carriers aged <35 years in the BRCA set 4·40 [1·14-24·36], p=0·031). INTERPRETATION: The presence of ovarian cancer, or factors known to affect risk for the disease (ie, age and BRCA1 germline mutations), were significantly associated with having a community type O cervicovaginal microbiota. Whether re-instatement of a community type L microbiome by using, for example, vaginal suppositories containing live lactobacilli, would alter the microbiomial composition higher up in the female genital tract and in the fallopian tubes (the site of origin of high-grade serous ovarian cancer), and whether such changes could translate into a reduced incidence of ovarian cancer, needs to be investigated. FUNDING: EU Horizon 2020 Research and Innovation Programme, EU Horizon 2020 European Research Council Programme, and The Eve Appeal.


Subject(s)
Carcinoma, Ovarian Epithelial/microbiology , Cervix Uteri/microbiology , Ovarian Neoplasms/microbiology , Vagina/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , BRCA1 Protein/genetics , Carcinoma, Ovarian Epithelial/genetics , Case-Control Studies , Female , Genetic Predisposition to Disease , Humans , Microbiota , Middle Aged , Ovarian Neoplasms/genetics , Risk Factors , Young Adult
3.
Eur J Cancer ; 116: 56-66, 2019 07.
Article in English | MEDLINE | ID: mdl-31173963

ABSTRACT

BACKGROUND: Hepatocellular carcinoma (HCC) is increasing globally. Prognostic biomarkers are urgently needed to guide treatment and reduce mortality. Tumour-derived circulating cell-free DNA (ctDNA) is a novel, minimally invasive means of determining genetic alterations in cancer. We evaluate the accuracy of ctDNA as a biomarker in HCC. METHODS: Plasma cell-free DNA, matched germline DNA and HCC tissue DNA were isolated from patients with HCC (n = 51) and liver cirrhosis (n = 10). Targeted, multiplex polymerase chain reaction ultra-deep sequencing was performed using a liver cancer-specific primer panel for genes ARID1A, ARID2, AXIN1, ATM, CTNNB1, HNF1A and TP53. Concordance of mutations in plasma ctDNA and HCC tissue DNA was determined, and associations with clinical outcomes were analysed. RESULTS: Plasma cell-free DNA was detected in all samples. Lower plasma cell-free DNA levels were seen in Barcelona Clinic Liver Cancer (BCLC A compared with BCLC stage B/C/D (median concentration 122.89 ng/mL versus 168.21 ng/mL, p = 0.041). 29 mutations in the eight genes (21 unique mutations) were detected in 18/51 patients (35%), median 1.5 mutations per patient (interquartile range 1-2). Mutations were most frequently detected in ARID1A (11.7%), followed by CTNNB1 (7.8%) and TP53 (7.8%). In patients with matched tissue DNA, all mutations detected in plasma ctDNA detected were confirmed in HCC DNA; however, 71% of patients had mutations identified in HCC tissue DNA that were not detected in matched ctDNA. CONCLUSION: ctDNA is quantifiable across all HCC stages and allows detection of mutations in key driver genes of hepatic carcinogenesis. This study demonstrates high specificity but low sensitivity of plasma ctDNA for detecting mutations in matched HCC tissue.


Subject(s)
Biomarkers, Tumor/blood , Biomarkers, Tumor/genetics , Carcinoma, Hepatocellular/genetics , Circulating Tumor DNA/genetics , Liver Neoplasms/genetics , Aged , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/pathology , Female , Humans , Liver Neoplasms/blood , Liver Neoplasms/pathology , Male , Middle Aged , Mutation , Sensitivity and Specificity
4.
Immunol Res ; 67(1): 123-133, 2019 02.
Article in English | MEDLINE | ID: mdl-30402710

ABSTRACT

Previous studies showed that interleukin (IL)-28B gene polymorphisms were associated with hepatitis C Virus (HCV) infection and treatment outcomes. We tested whether single-nucleotide polymorphisms (SNPs) in IL-28A and IL-28B are associated with HCV infection among Egyptians with HCV genotype 4 infections. We enrolled 144 chronic HCV patients, 72 spontaneously resolved HCV subjects, and 69 healthy controls. Four SNPs in IL-28A and IL-28B genes (IL-28A.rs12980602, IL-28B.rs12979860, IL-28B.rs8099917, and IL-28B.rs8103142) were genotyped. The most frequent IL-28B haplotype "TCT" was significantly more frequent in HCV-infected subjects than in HCV negative subjects (62.2% vs. 48.6%, respectively; p = 0.005). The frequency of IL-28A.rs12980602 "T" allele was significantly higher than the "C" allele in healthy controls compared to HCV-infected subjects (p < 0.001) with the "TT" genotype significantly higher in healthy controls compared to HCV-infected subjects (p < 0.001) with no association with viral load (p = 0.11) among chronically infected subjects. The results, also, confirmed the previous role of IL-28B SNPs in predicting HCV infection outcome. Importantly, IL-28B.rs8099917 "TT" genotype was significantly associated with low viral load in HCV-infected subjects, while the remaining three SNPs did not. The three IL-28B SNPs were in linkage disequilibrium (D' > 0.68; r2 > 0.43) for all comparisons in HCV patients, while there was no linkage disequilibrium of IL-28A polymorphisms and the three IL-28B SNPs. In conclusion, IL-28A.rs12980602 and IL-28B.rs8103142 TT genotype could be protective against HCV infection. Also, IL-28B.rs12979860, IL-28B.rs8099917, and IL-28B.rs8103142 SNPs predicted the outcome of HCV infection among genotype-4-infected Egyptians. Moreover, IL-28B.rs8099917 SNP affected the viral load in chronic HCV patients.


Subject(s)
Genotype , Hepacivirus/physiology , Hepatitis C/genetics , Interferons/genetics , Interleukins/genetics , Adult , Egypt , Female , Gene Frequency , Genetic Association Studies , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide , Young Adult
5.
Methods Mol Biol ; 1586: 337-344, 2017.
Article in English | MEDLINE | ID: mdl-28470616

ABSTRACT

Site-specific biotinylation of proteins is often the method of choice to enable efficient immobilization of a protein on a surface without interfering with protein folding. The tight interaction of biotin and streptavidin is frequently used to immobilize an antigen during phage display selections of binders. Here we describe a method of in vivo biotinylation of proteins during expression in E. coli, by tagging the protein with the short biotin acceptor peptide sequence, Avi tag, and co-expression of the E. coli biotin ligase (BirA) resulting in precise biotinylation of a specific lysine residue in the tag.


Subject(s)
Antigens/chemistry , Antigens/genetics , Escherichia coli/genetics , Immobilized Proteins/chemistry , Immobilized Proteins/genetics , Animals , Biotin/chemistry , Biotinylation , Carbon-Nitrogen Ligases/chemistry , Carbon-Nitrogen Ligases/genetics , Cloning, Molecular/methods , Escherichia coli/chemistry , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Gene Expression , Genetic Vectors/genetics , Humans , Repressor Proteins/chemistry , Repressor Proteins/genetics , Streptavidin/chemistry
6.
Psychiatr Genet ; 27(3): 110-115, 2017 06.
Article in English | MEDLINE | ID: mdl-28346242

ABSTRACT

Associations between the γ-aminobutyric acid type-A receptors (GABAA) and alcohol dependence risk have been reported, although the receptor subunit driving the association is unclear. Recent work in mice has highlighted a possible role for variants in the Gabr ß1 subunit (Gabrß1) in alcohol dependence risk, although this gene does not contain any common nonsynonymous variants in humans. However, the GABAA receptor is a heteropentamer so multiple potential variants within the gene complex could generate the alcohol dependence phenotype. The association between GABRß1 variants and alcohol dependence risk was explored in a British and Irish population of alcohol-dependent cases (n=450) and ancestrally-matched controls screened to exclude current or historical alcohol misuse (n=555). Twelve common single nucleotide polymorphisms (SNPs) and a rare nonsynonymous variant, rs41311286, were directly genotyped; imputation was then performed across the whole gene. No allelic association was observed between alcohol dependence risk and any of the directly genotyped or imputed SNPs. However, post-hoc testing for genotypic association identified five common intronic SNPs that showed modest evidence for association after correction for multiple testing; two, rs76112682 and rs141719901, were in complete linkage disequilibrium [Pcorrected=0.02, odds ratio (95% confidence interval)=5.9 (1.7-2.06)]. These findings provide limited support for an association between GABRß1 and the risk for developing alcohol dependence; further testing in expanded cohorts may be warranted.


Subject(s)
Alcoholism/genetics , GA-Binding Protein Transcription Factor/genetics , Adult , Aged , Aged, 80 and over , Alleles , Female , GA-Binding Protein Transcription Factor/metabolism , Gene Frequency , Genetic Association Studies , Genetic Predisposition to Disease , Genetic Variation , Haplotypes , Humans , Linkage Disequilibrium , Male , Middle Aged , Polymorphism, Single Nucleotide , White People/genetics
7.
Transl Res ; 183: 137-154, 2017 05.
Article in English | MEDLINE | ID: mdl-28056336

ABSTRACT

Circulating cell-free DNA (cfDNA) is DNA released from necrotic or apoptotic cells into the bloodstream. While both healthy cells and cancer cells release cfDNA, tumors are associated with higher levels of tumor-derived circulating cell-free DNA (ctDNA) detectable in blood. Absolute levels of ctDNA and its genetic mutations and epigenetic changes show promise as potentially useful biomarkers of tumor biology, progression, and response to therapy. Moreover, studies have demonstrated the discriminative accuracy of ctDNA levels for diagnosis of gastrointestinal cancer compared with benign inflammatory diseases. Therefore, ctDNA detected in blood offers a minimally invasive and easily repeated "liquid biopsy" of cancer, facilitating real-time dynamic analysis of tumor behavior that could revolutionize both clinical and research practices in oncology. In this review, we provide a critical summary of the evidence for the utility of ctDNA as a diagnostic and prognostic biomarker in gastrointestinal malignancies.


Subject(s)
Biomarkers, Tumor/blood , DNA, Neoplasm/blood , Gastrointestinal Neoplasms/blood , Gastrointestinal Neoplasms/genetics , Humans
8.
Hepatol Int ; 9(2): 251-7, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25788203

ABSTRACT

BACKGROUND/PURPOSE: Single-nucleotide polymorphisms (SNPs) around the interferon lambda 3 (IFNL3; also known as interleukin 28B; IL28B) gene are associated with spontaneous hepatitis C virus (HCV) clearance. Interferon lambda 4 (IFNL4).ss469415590, in linkage disequilibrium (LD) with IFNL3.rs12979860 among the Caucasian population, has recently been identified as a potential functional variant. Our objective was to assess the LD between IFNL3.rs12979860 and IFNL4.ss469415590 and to compare their effect on the outcome of HCV infection among Egyptians, mainly infected with HCV genotype 4. METHODS: One-hundred and eighty-five Egyptian HCV patients (77 spontaneous resolvers and 108 chronic subjects), and 122 healthy controls were genotyped for both IL28B.rs12979860 and IFNL4.ss469415590. Logistic regression models including factors with univariate association with the outcome of infection were calculated for each genetic marker. The LD was also calculated for the 122 healthy controls. RESULTS: The CC genotype of IFNL3.rs12979860 was more frequent among individuals with HCV spontaneous resolution than among those with chronic infection (57 vs. 27%; adjusted OR 3.84; 95% CI 2.02-7.30; p < 0.0001). Also, the TT/TT genotype of IFNL4.ss469415590 was more frequent among individuals with spontaneous resolution (49 vs. 20%; adjusted OR 4.17; 95% CI 2.12-8.19; p < 0.0001). Both markers were in LD (D' = 0.96; r (2) = 0.84). CONCLUSION: The IFNL3.rs12979860 and IFNL4.ss469415590 variants have comparable effects on spontaneous resolution of HCV among Egyptians, for whom both markers are closely linked.


Subject(s)
Black People/genetics , Hepatitis C, Chronic/genetics , Interleukins/genetics , Linkage Disequilibrium , Adult , Egypt , Female , Genotype , Hepacivirus/genetics , Humans , Interferons , Male , Middle Aged , Polymorphism, Single Nucleotide , Remission, Spontaneous , Viral Load/genetics , Young Adult
9.
BMC Med Genet ; 15: 104, 2014 Oct 05.
Article in English | MEDLINE | ID: mdl-25287681

ABSTRACT

BACKGROUND: Variants of the interferon-lambda3 (IFNL3) gene have been associated with both spontaneous and treatment induced clearance of HCV infection. Attempts to link polymorphisms of the IFNL3 gene with variation in the level of IFNL3 expression have been inconclusive. This is partially due to the difficulty to design assays distinguishing IFNL3 from IFNL2. METHODS: In this study an allele specific real-time PCR (RT-PCR) assay was developed which allows the relative quantification of the two IFNL3 transcripts in cells heterozygous for SNP IFNL3.rs4803217 in the 3'UTR of the IFNL3 gene. This SNP is in strong linkage disequilibrium (LD) with the predictive marker rs12979860. RESULTS: Raji cells showed two-fold increased levels of IFNL3.rs4803217 C-allele expression. In peripheral blood mononuclear cells (PBMCs) of eight uninfected donors, two donors showed increased IFNL3.rs4803217 C-allele expression. CONCLUSION: This indicates that allele specific differences in IFNL3 expression vary between individuals and might contribute to the variety of outcomes in HCV infected patients.


Subject(s)
Hepatitis C/genetics , Interleukins/genetics , RNA, Messenger/analysis , Real-Time Polymerase Chain Reaction/methods , Alleles , Cell Line , Hepatitis C/drug therapy , Hepatitis C/immunology , Humans , Interferons , Interleukins/metabolism , Leukocytes, Mononuclear/metabolism , Polymorphism, Single Nucleotide , Sensitivity and Specificity
10.
Nat Commun ; 4: 2816, 2013.
Article in English | MEDLINE | ID: mdl-24281383

ABSTRACT

Alcohol dependence is a common, complex and debilitating disorder with genetic and environmental influences. Here we show that alcohol consumption increases following mutations to the γ-aminobutyric acidA receptor (GABAAR) ß1 subunit gene (Gabrb1). Using N-ethyl-N-nitrosourea mutagenesis on an alcohol-averse background (F1 BALB/cAnN x C3H/HeH), we develop a mouse model exhibiting strong heritable preference for ethanol resulting from a dominant mutation (L285R) in Gabrb1. The mutation causes spontaneous GABA ion channel opening and increases GABA sensitivity of recombinant GABAARs, coupled to increased tonic currents in the nucleus accumbens, a region long-associated with alcohol reward. Mutant mice work harder to obtain ethanol, and are more sensitive to alcohol intoxication. Another spontaneous mutation (P228H) in Gabrb1 also causes high ethanol consumption accompanied by spontaneous GABA ion channel opening and increased accumbal tonic current. Our results provide a new and important link between GABAAR function and increased alcohol consumption that could underlie some forms of alcohol abuse.


Subject(s)
Alcohol Drinking/genetics , Receptors, GABA-A/genetics , Alcohol-Related Disorders/genetics , Animals , Female , Genes, Dominant , HEK293 Cells , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C3H , Nucleus Accumbens/physiology , Point Mutation , Receptors, GABA-A/metabolism
11.
Chem Sci ; 4(8): 3110-3117, 2013 Aug 01.
Article in English | MEDLINE | ID: mdl-26682036

ABSTRACT

2-Oxoglutarate and iron dependent oxygenases are therapeutic targets for human diseases. Using a representative 2OG oxygenase panel, we compare the inhibitory activities of 5-carboxy-8-hydroxyquinoline (IOX1) and 4-carboxy-8-hydroxyquinoline (4C8HQ) with that of two other commonly used 2OG oxygenase inhibitors, N-oxalylglycine (NOG) and 2,4-pyridinedicarboxylic acid (2,4-PDCA). The results reveal that IOX1 has a broad spectrum of activity, as demonstrated by the inhibition of transcription factor hydroxylases, representatives of all 2OG dependent histone demethylase subfamilies, nucleic acid demethylases and γ-butyrobetaine hydroxylase. Cellular assays show that, unlike NOG and 2,4-PDCA, IOX1 is active against both cytosolic and nuclear 2OG oxygenases without ester derivatisation. Unexpectedly, crystallographic studies on these oxygenases demonstrate that IOX1, but not 4C8HQ, can cause translocation of the active site metal, revealing a rare example of protein ligand-induced metal movement.

12.
Dev Sci ; 15(4): 506-15, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22709400

ABSTRACT

In striking contrast to adults, in children sleep following training a motor task did not induce the expected (offline) gain in motor skill performance in previous studies. Children normally perform at distinctly lower levels than adults. Moreover, evidence in adults suggests that sleep dependent offline gains in skill essentially depend on the pre-sleep level of performance. Against this background, we asked whether improving children's performance on a motor sequence learning task by extended training to levels approaching those of adults would enable sleep-associated gains in motor skill in this age group also. Children (4-6 years) and adults (18-35 years) performed on the motor sequence learning task (button-box task) before and after ~2-hour retention intervals including either sleep (midday nap) or wakefulness. Whereas one group of children and adults, respectively, received the standard amount of 10 blocks of training before retention intervals of sleep or wakefulness, a further group of children received an extended training on 30 blocks (distributed across 3 days). A further group of adults received a restricted training on only two blocks before the retention intervals. Children after standard training reached lowest performance levels, whereas in adults performance after standard training was highest. Children with extended training and adults after reduced training reached intermediate performance levels. Only at these intermediate performance levels did sleep induce significant gains in motor sequence skill, whereas performance did not benefit from sleep in the low-performing children or in the high-performing adults. Spindle counts in the post-training nap were correlated with performance gains at retrieval only in the adults benefitting from sleep. We conclude that, across age groups, sleep induces the most robust gain in motor skill at an intermediate pre-sleep performance level. In low-performing children sleep-dependent improvements in skill may be revealed only after enhancing the pre-sleep performance level by extended training.


Subject(s)
Learning/physiology , Memory/physiology , Sleep/physiology , Wakefulness/physiology , Adult , Child , Child, Preschool , Female , Humans , Male , Motor Skills/physiology , Polysomnography , Retention, Psychology/physiology , Task Performance and Analysis , Time Factors , Young Adult
13.
Gastroenterology ; 141(1): 320-5, 325.e1-2, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21600205

ABSTRACT

BACKGROUND & AIMS: Polymorphisms in the interleukin-28B (IL28B) gene are associated with outcomes from infection with hepatitis C virus (HCV). However, the role of these polymorphisms in protecting injection drug users who are at high risk for HCV infection but do not have detectable antibodies against HCV or HCV RNA (exposed uninfected) has not been demonstrated. We investigated whether these individuals have the IL28B genotype rs12979860-CC, which protects some individuals against HCV infection. METHODS: Seventy-four exposed uninfected individuals, 89 spontaneous resolvers, and 234 chronically infected individuals were genotyped to determine single nucleotide polymorphisms at IL28B.rs12979860. RESULTS: Exposed, uninfected individuals had a significantly lower frequency of the protective genotype (rs12979860-CC) than anti-HCV-positive spontaneous resolvers (41.9% vs 69.7%, respectively; P=.0005; odds ratio [OR], 0.31; 95% confidence interval [CI]: 0.16-0.60) but a similar frequency to patients who were chronically infected (41.9% vs 43.6%, respectively; P=ns). However, exposed, uninfected individuals had a significantly higher frequency of homozygosity for killer cell immunoglobulin-like receptor 2DL3:group 1 HLA-C (KIR2DL3:HLA-C1) than those with chronic infection (31.1% vs 13.3%, respectively; P=.0008; OR, 2.95; 95% CI: 1.59-5.49). For patients who spontaneously resolved infection, IL28B and KIR:HLA protected, independently, against chronic HCV infection, based on logistic regression and synergy analyses (synergy factor, 1.3; 95% CI: 0.37-4.75; P synergy=.6). CONCLUSIONS: IL28B and KIR2DL3:HLA-C1 are independently associated with spontaneous resolution of viremia following HCV exposure. Resistance to HCV infection in exposed uninfected cases is associated with homozygosity for KIR2DL3:HLA-C1 but not the single nucleotide polymorphism IL28B.rs12979860. Uninfected individuals are therefore a distinct population from patients who spontaneously resolve HCV infection. Distinct, nonsynergistic innate immune mechanisms can determine outcomes of HCV exposure.


Subject(s)
Hepatitis C, Chronic/genetics , Hepatitis C, Chronic/prevention & control , Hepatitis C/genetics , Hepatitis C/prevention & control , Immunity, Innate/genetics , Interleukins/genetics , Polymorphism, Single Nucleotide , Substance Abuse, Intravenous/complications , Adult , Disease Progression , Female , Gene Frequency , Genetic Predisposition to Disease , HLA-C Antigens/genetics , Hepacivirus/genetics , Hepacivirus/immunology , Hepatitis C/diagnosis , Hepatitis C/immunology , Hepatitis C Antibodies/blood , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/immunology , Humans , Interferons , Logistic Models , Male , Middle Aged , Odds Ratio , Phenotype , RNA, Viral/blood , Receptors, KIR2DL3/genetics , Remission, Spontaneous , Risk Assessment , Risk Factors , United Kingdom , Viral Load
14.
J Inherit Metab Dis ; 34(3): 671-6, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21445611

ABSTRACT

Fumarate hydratase catalyzes the stereospecific hydration across the olefinic double bond in fumarate leading to L-malate. The enzyme is expressed in mitochondrial and cytosolic compartments, and participates in the Krebs cycle in mitochondria, as well as in regulation of cytosolic fumarate levels. Fumarate hydratase deficiency is an autosomal recessive trait presenting as metabolic disorder with severe encephalopathy, seizures and poor neurological outcome. Heterozygous mutations are associated with a predisposition to cutaneous and uterine leiomyomas and to renal cancer. The crystal structure of human fumarate hydratase shows that mutations can be grouped into two distinct classes either affecting structural integrity of the core enzyme architecture, or are localized around the enzyme active site. An interactive version of this manuscript (which may contain additional mutations appended after acceptance of this manuscript) may be found on the SSIEM website at: http://www.ssiem.org/resources/structures/FH .


Subject(s)
Fumarate Hydratase/chemistry , Fumarate Hydratase/genetics , Metabolism, Inborn Errors/etiology , Catalytic Domain/genetics , Crystallography, X-Ray , Fumarate Hydratase/deficiency , Humans , Metabolism, Inborn Errors/genetics , Mitochondrial Diseases/etiology , Mitochondrial Diseases/genetics , Models, Molecular , Mutant Proteins/chemistry , Mutation/physiology , Protein Conformation , Protein Folding , Structure-Activity Relationship
15.
Hepatology ; 51(4): 1168-75, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20077564

ABSTRACT

UNLABELLED: Natural killer cells are a key component in the immune control of viral infections. Their functions are controlled by inhibitory receptors for major histocompatability complex (MHC) class I, including the killer cell immunoglobulin-like receptors (KIR). KIR2DL3 in combination with its cognate human leukocyte antigen (HLA)-C ligand has been shown to be associated with spontaneous resolution of viremia following hepatitis C virus (HCV) infection. In order to determine if this gene combination is advantageous across all potential outcomes following HCV exposure, we studied individuals with apparent resistance to HCV infection who remain seronegative and aviremic despite long-term injection drug use and also individuals chronically infected with HCV who successfully clear HCV with treatment. Homozygosity for KIR2DL3 in combination with group 1 HLA-C allotypes was more frequent in exposed seronegative aviremic individuals as compared to those with chronic HCV (25.0% versus 9.7%, P = 0.003, odds ratio [OR] = 3.1, 95% confidence interval [CI] = 1.3-7.1) in a model similar to that found for those spontaneously resolving HCV. In individuals undergoing treatment for HCV, those with KIR2DL3 and group 1 HLA-C were more likely to make a sustained virological response (SVR) (P = 0.013, OR = 2.3, 95% CI = 1.1-4.5). KIR and HLA-C protection in both treatment response and spontaneously resolving HCV was validated at the allelic level, in which KIR2DL3-HLA-Cw*03 was associated with SVR (P = 0.004, OR = 3.4, 95% CI = 1.5-8.7) and KIR2DL3/KIR2DL3-HLA-Cw*03 was associated with spontaneous resolution of HCV infection (P = 0.01, OR = 2.3, 95% CI = 1.2-4.4). CONCLUSION: KIR and HLA-C genes are consistently beneficial determinants in the outcome of HCV infection. This advantage extends to the allelic level for both gene families.


Subject(s)
HLA-C Antigens/physiology , Hepatitis C/immunology , Receptors, KIR2DL3/physiology , Adult , Female , HLA-C Antigens/genetics , Humans , Male , Middle Aged , Receptors, KIR2DL3/genetics
16.
J Gastroenterol Hepatol ; 23(9): 1403-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18005014

ABSTRACT

BACKGROUND AND AIM: Tissue injury leads to activation of coagulation and generation of thrombin. Inhibition of thrombin receptor protease-activated receptor 1 (PAR-1) has been shown to reduce liver fibrosis in animals. This study aimed to evaluate the effect of PAR-1 gene polymorphism on rate of liver fibrosis (RF) in chronic hepatitis C. METHODS: Polymorphisms studied: C > T transition 1426 bp upstream of translation start site (-1426C/T), 13 bp repeat of preceding -506 5'-CGGCCGCGGGAAG-3' sequence (-506I/D), and A > T transversion in intervening sequence (IVS) 14 bp upstream of exon-2 start site (IVS-14A/T). A total of 287 European and 90 Brazilian patients were studied. RESULTS: 1426C/T polymorphism: There was a trend to higher RF in patients with the TT genotype (P = 0.06) and an association between genotype CC and slow fibrosis (P = 0.03) in Europeans. In males, RF was significantly higher in those with the TT genotype compared to CT (P = 0.003) and CC (P = 0.007). There was a significant association between TT and fast fibrosis (P = 0.04). This was confirmed in an independent cohort of Brazilians where RF was higher in TT than in CC (P = 0.03). Analysis of -506I/D showed no difference in RF and distribution of slow/fast fibrosis among different genotypes in both populations. Analysis of IVS-14A/T showed no difference between genotypes. CONCLUSION: In conclusion, these findings suggest that PAR-1 receptor polymorphisms influence the progression of liver fibrosis.


Subject(s)
Hepatitis C, Chronic/genetics , Liver Cirrhosis/genetics , Polymorphism, Genetic , Receptor, PAR-1/genetics , Adult , Brazil , Disease Progression , Europe , Exons , Female , Genetic Predisposition to Disease , Hepacivirus/genetics , Hepatitis C, Chronic/complications , Humans , Liver Cirrhosis/virology , Logistic Models , Male , Odds Ratio , Regulatory Sequences, Nucleic Acid , Risk Assessment , Risk Factors , Young Adult
17.
Liver Int ; 27(8): 1134-43, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17845543

ABSTRACT

BACKGROUND: Two receptor chains, IL-10RA and IL-10RB, are known to mediate the functions of interleukin-10 (IL-10), which has been shown to be involved in the progression of persistent hepatitis C virus (HCV) infection. Little information is available on the role of host genetic variation in IL-10 receptor genes and outcome of HCV infection. IL-22, an IL-10 homologue, shares the IL-10RB receptor chain with IL-10 and has antiviral properties. We investigated the possible role of polymorphisms in the IL-10RA and IL-22 genes in hepatitis C disease pathogenesis. METHODS: This study population consisted of 631 HCV patients, recruited from several hepatology clinics across Europe. We genotyped four single-nucleotide polymorphisms (SNPs) in the IL-10RA and six SNPs in the IL-22 gene by ligation detection reaction or restriction fragment length polymorphism. Outcome of HCV infection was assessed according to viral clearance, treatment response, severity of fibrosis and overall inflammation. CONCLUSIONS: Variation in IL-10RA appeared to be correlated with response to treatment and inflammation. Two SNPs in IL-22 affected treatment response and viral clearance respectively. We furthermore report on allele and haplotype frequencies and linkage disequilibrium for IL-10RA and IL-22. Our results indicate that genetic variation in these genes may play a modulatory role in the outcome of hepatitis C infection.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C/drug therapy , Interleukin-10 Receptor alpha Subunit/genetics , Interleukins/genetics , Polymorphism, Single Nucleotide , Adult , Case-Control Studies , DNA Mutational Analysis , Europe , Female , Gene Frequency , Haplotypes , Hepatitis C/genetics , Humans , Linkage Disequilibrium , Male , Treatment Outcome , Interleukin-22
18.
Proc Natl Acad Sci U S A ; 103(24): 9148-53, 2006 Jun 13.
Article in English | MEDLINE | ID: mdl-16757563

ABSTRACT

Persistent hepatitis B virus infection is a major risk factor for hepatocellular carcinoma, the most frequent cancer in some developing countries. Up to 95% of those infected at birth and 15% of those infected after the neonatal period fail to clear hepatitis B virus, together resulting in approximately 350 million persistent carriers worldwide. Via a whole genome scan in Gambian families, we have identified a major susceptibility locus as a cluster of class II cytokine receptor genes on chromosome 21q22. Coding changes in two of these genes, the type I IFN receptor gene, IFN-AR2, and the IL-10RB gene that encodes a receptor chain for IL-10-related cytokines including the IFN-lambdas, are associated with viral clearance (haplotype P value = 0.0003), and in vitro assays support functional roles for these variants in receptor signaling.


Subject(s)
Carrier State , Hepatitis B, Chronic , Membrane Proteins/genetics , Multigene Family , Receptors, Interferon/genetics , Receptors, Interleukin/genetics , Carcinoma, Hepatocellular/virology , Cell Line , Gambia , Genetic Markers , Genetic Predisposition to Disease , Genotype , Hepatitis B, Chronic/genetics , Hepatitis B, Chronic/immunology , Humans , Linkage Disequilibrium , Liver Neoplasms/virology , Membrane Proteins/metabolism , Polymorphism, Genetic , Receptor, Interferon alpha-beta , Receptors, Cytokine , Receptors, Interferon/metabolism , Receptors, Interleukin/metabolism , Receptors, Interleukin-10 , Sequence Analysis, DNA , Tumor Necrosis Factor-alpha/metabolism
19.
J Interferon Cytokine Res ; 24(10): 585-93, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15626155

ABSTRACT

Interferon-alpha2 (IFN-alpha2) is used as standard treatment of patients with chronic hepatitis C (cHCV), but little is known about the immunomodulatory effects of this cytokine in vivo. We have studied immunologic parameters in freshly isolated peripheral blood mononuclear cells (PBMC) of 26 patients with cHCV 12 h before and 12 h after the first s.c. injection of 5-6 MU IFN-alpha2. In PBMC obtained after IFN injection, a substantial increase in IL-10 production after antigen-specific and nonspecific stimulation was observed, whereas IFN-gamma production and proliferation were significantly diminished compared with PBMC obtained before IFN injection. Patients were stratified according to single nucleotide polymorphisms (SNPs) in the interleukin-10 (IL-10) promoter, which have been associated with the response to IFN therapy. Induction of IL-10 and suppression of IFN-gamma levels were more prominent in patients with genotype CC at position -592 (n = 15) compared with patients with genotype AA/AC (n = 11). In conclusion, our data indicate that IFN-alpha2 therapy can potently enhance IL-10 and suppress IFN-gamma production of PBMC, which is, at least partially, dependent on an SNP in the IL-10 promoter. This suggests an autoregulatory role of IL-10 in IFN therapy.


Subject(s)
Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/immunology , Interferon-alpha/therapeutic use , Interleukin-10/biosynthesis , Adult , Aged , Base Sequence , DNA/genetics , Female , Genotype , Hepacivirus/genetics , Hepatitis C, Chronic/genetics , Hepatitis C, Chronic/virology , Homeostasis , Humans , In Vitro Techniques , Interferon alpha-2 , Interferon-gamma/biosynthesis , Interleukin-10/genetics , Leukocytes, Mononuclear/immunology , Male , Middle Aged , Polymorphism, Single Nucleotide , Promoter Regions, Genetic , Recombinant Proteins
20.
Immunogenetics ; 55(6): 362-9, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12942209

ABSTRACT

The natural outcome and response to treatment in hepatitis C virus (HCV) infection varies between individuals. Whereas some variation may be attributable to viral and environmental variables, it is probable that host genetic background also plays a significant role. Interleukin (IL)-10 has a key function in the regulation of cellular immune responses and in the suppression of pro-inflammatory cytokine secretion. Functional polymorphisms in the IL-10 gene have been described. We investigated the role of these polymorphisms in the outcome of HCV infection, treatment response and development of fibrosis in a case-control association study. Self-limiting infection was associated with the IL-10 (-592) AA genotype (OR=2.05; P=0.028). Persistent infection was associated with the IL-10 (-1082) GG genotype (OR=0.48; P=0.018). Sustained response to interferon therapy was associated with the IL-10 (-1082) GG genotype (OR=2.28; P=0.005) and the haplotype GCC (OR=2.27; P=0.020). The IL-10 (-1082) AA genotype and the ATA/ATA and ACC/ACC homozygous haplotypes were more frequent among patients with rapid fibrosis. Furthermore, the microsatellites IL-10.R and IL-10.G were associated with interferon response with IL-10R.2 conveying susceptibility (OR=1.80; P=0.034), and IL-10R.3 and IL-10.G13 being protective (OR=0.47; P=0.003 and OR=0.59; P=0.042, respectively). We conclude that polymorphisms in the IL-10 promoter appear to have some influence on the outcome of HCV infection, treatment and development of fibrosis.


Subject(s)
Hepatitis C/genetics , Interleukin-10/genetics , Promoter Regions, Genetic , Disease Progression , Female , Fibrosis , Haplotypes , Hepatitis C/physiopathology , Hepatitis C/therapy , Humans , Male , Polymorphism, Genetic , Treatment Outcome
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