Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
Nat Commun ; 13(1): 449, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35105882

RESUMO

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.


Assuntos
Neoplasias da Mama/genética , Metilação de DNA , Epigenômica/métodos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Mama/citologia , Mama/metabolismo , Neoplasias da Mama/metabolismo , Colo do Útero/citologia , Colo do Útero/metabolismo , Ilhas de CpG , Epigenoma , Células Epiteliais/metabolismo , Feminino , Humanos , Mutação , Prognóstico , Curva ROC
2.
Lancet Oncol ; 20(8): 1171-1182, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31300207

RESUMO

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.


Assuntos
Carcinoma Epitelial do Ovário/microbiologia , Colo do Útero/microbiologia , Neoplasias Ovarianas/microbiologia , Vagina/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína BRCA1/genética , Carcinoma Epitelial do Ovário/genética , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Microbiota , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética , Fatores de Risco , Adulto Jovem
3.
Eur J Cancer ; 116: 56-66, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31173963

RESUMO

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.


Assuntos
Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , DNA Tumoral Circulante/genética , Neoplasias Hepáticas/genética , Idoso , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Sensibilidade e Especificidade
4.
Transl Res ; 183: 137-154, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28056336

RESUMO

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.


Assuntos
Biomarcadores Tumorais/sangue , DNA de Neoplasias/sangue , Neoplasias Gastrointestinais/sangue , Neoplasias Gastrointestinais/genética , Humanos
5.
Chem Sci ; 4(8): 3110-3117, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26682036

RESUMO

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.

6.
J Inherit Metab Dis ; 34(3): 671-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21445611

RESUMO

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 .


Assuntos
Fumarato Hidratase/química , Fumarato Hidratase/genética , Erros Inatos do Metabolismo/etiologia , Domínio Catalítico/genética , Cristalografia por Raios X , Fumarato Hidratase/deficiência , Humanos , Erros Inatos do Metabolismo/genética , Doenças Mitocondriais/etiologia , Doenças Mitocondriais/genética , Modelos Moleculares , Proteínas Mutantes/química , Mutação/fisiologia , Conformação Proteica , Dobramento de Proteína , Relação Estrutura-Atividade
7.
Proc Natl Acad Sci U S A ; 103(24): 9148-53, 2006 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-16757563

RESUMO

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.


Assuntos
Portador Sadio , Hepatite B Crônica , Proteínas de Membrana/genética , Família Multigênica , Receptores de Interferon/genética , Receptores de Interleucina/genética , Carcinoma Hepatocelular/virologia , Linhagem Celular , Gâmbia , Marcadores Genéticos , Predisposição Genética para Doença , Genótipo , Hepatite B Crônica/genética , Hepatite B Crônica/imunologia , Humanos , Desequilíbrio de Ligação , Neoplasias Hepáticas/virologia , Proteínas de Membrana/metabolismo , Polimorfismo Genético , Receptor de Interferon alfa e beta , Receptores de Citocinas , Receptores de Interferon/metabolismo , Receptores de Interleucina/metabolismo , Receptores de Interleucina-10 , Análise de Sequência de DNA , Fator de Necrose Tumoral alfa/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA