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1.
Behav Genet ; 46(2): 151-69, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26392368

RESUMO

The mu1 opioid receptor gene, OPRM1, has long been a high-priority candidate for human genetic studies of addiction. Because of its potential functional significance, the non-synonymous variant rs1799971 (A118G, Asn40Asp) in OPRM1 has been extensively studied, yet its role in addiction has remained unclear, with conflicting association findings. To resolve the question of what effect, if any, rs1799971 has on substance dependence risk, we conducted collaborative meta-analyses of 25 datasets with over 28,000 European-ancestry subjects. We investigated non-specific risk for "general" substance dependence, comparing cases dependent on any substance to controls who were non-dependent on all assessed substances. We also examined five specific substance dependence diagnoses: DSM-IV alcohol, opioid, cannabis, and cocaine dependence, and nicotine dependence defined by the proxy of heavy/light smoking (cigarettes-per-day >20 vs. ≤ 10). The G allele showed a modest protective effect on general substance dependence (OR = 0.90, 95% C.I. [0.83-0.97], p value = 0.0095, N = 16,908). We observed similar effects for each individual substance, although these were not statistically significant, likely because of reduced sample sizes. We conclude that rs1799971 contributes to mechanisms of addiction liability that are shared across different addictive substances. This project highlights the benefits of examining addictive behaviors collectively and the power of collaborative data sharing and meta-analyses.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Receptores Opioides mu/genética , Transtornos Relacionados ao Uso de Substâncias/genética , População Branca/genética , Adolescente , Adulto , Alelos , Estudos de Casos e Controles , Criança , Estudos de Coortes , Frequência do Gene/genética , Humanos , Masculino , Tamanho da Amostra
2.
Cells ; 13(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38607072

RESUMO

The field cancerization theory is an important paradigm in head and neck carcinoma as its oncological repercussions affect treatment outcomes in diverse ways. The aim of this study is to assess the possible interconnection between peritumor mucosa and the process of tumor neoangiogenesis. Sixty patients with advanced laryngeal carcinoma were enrolled in this study. The majority of patients express a canonical HIF-upregulated proangiogenic signature with almost complete predominancy of HIF-1α overexpression and normal expression levels of the HIF-2α isoform. Remarkably, more than 60% of the whole cohort also exhibited an HIF-upregulated proangiogenic signature in the peritumoral benign mucosa. Additionally, the latter subgroup had a distinctly shifted phenotype towards HIF-2α upregulation compared to the one in tumor tissue, i.e., a tendency towards an HIF switch is observed in contrast to the dominated by HIF-1α tumor phenotype. ETS-1 displays stable and identical significant overexpression in both the proangiogenic phenotypes present in tumor and peritumoral mucosa. In the current study, we report for the first time the existence of an abnormal proangiogenic expression profile present in the peritumoral mucosa in advanced laryngeal carcinoma when compared to paired distant laryngeal mucosa. Moreover, we describe a specific phenotype of this proangiogenic signature that is significantly different from the one present in tumor tissue as we delineate both phenotypes, quantitively and qualitatively. This finding is cancer heterogeneity, per se, which extends beyond the "classical" borders of the malignancy, and it is proof of a strong interconnection between field cancerization and one of the classical hallmarks of cancer-the process of tumor neoangiogenesis.


Assuntos
Carcinoma , Neoplasias Laríngeas , Humanos , Neoplasias Laríngeas/genética , Neovascularização Patológica/genética , Mucosa , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
3.
Sci Rep ; 12(1): 17051, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224266

RESUMO

Laryngeal carcinoma is still a worldwide burden that has shown no significant improvement during the last few decades regarding definitive treatment strategies. The lack of suitable biomarkers for personalized treatment protocols and delineating field cancerization prevents further progress in clinical outcomes. In the light of this perspective, MicroRNAs could be promising biomarkers both in terms of diagnostic and prognostic value. The aim of this prospective study is to find strong prognostic microRNA biomarkers for advanced laryngeal carcinoma and molecular signatures of field cancerization. Sixty patients were enrolled and four samples were collected from each patient: tumor surface and depth, peritumor normal mucosa, and control distant laryngeal mucosa. Initially, a global microRNA profile was conducted in twelve patients from the whole cohort and subsequently, we validated a selected group of 12 microRNAs with RT-qPCR. The follow-up period was 24 months (SD ± 13 months). Microarray expression profile revealed 59 dysregulated microRNAs. The validated expression levels of miR-93-5p (χ2(2) = 4.68, log-rank p = 0.03), miR-144-3p (χ2(2) = 4.53, log-rank p = 0.03) and miR-210-3p (χ2(2) = 4.53, log-rank p = 0.03) in tumor samples exhibited strong association with recurrence-free survival as higher expression levels of these genes predict worse outcome. Tumor suppressor genes miR-144-3p (mean rank 1.58 vs 2.14 vs 2.29, p = 0.000) and miR-145-5p (mean rank 1.57 vs 2.15 vs 2.28, p = 0.000) were significantly dysregulated in peritumor mucosa with a pattern of expression consistent with paired tumor samples thus revealing a signature of field cancerization in laryngeal carcinoma. Additionally, miR-1260b, miR-21-3p, miR-31-3p and miR-31-5p were strongly associated with tumor grade. Our study reports the first global microRNA profile specifically in advanced laryngeal carcinoma that includes survival analysis and investigates the molecular signature of field cancerization. We report two strong biomarkers of field cancerization and three predictors for recurrence in advance stage laryngeal cancer.


Assuntos
Carcinoma , Neoplasias Laríngeas , MicroRNAs , Biomarcadores Tumorais/genética , Carcinoma/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Prognóstico , Estudos Prospectivos
4.
Folia Med (Plovdiv) ; 62(2): 244-252, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32666764

RESUMO

Laryngeal squamous cell carcinoma is a common malignancy in men. Bulgaria is one of the countries in Europe with the highest incidence and mortality rates of the aggressive, severe disease of laryngeal cancer. Proven etiological factors are the abuse of tobacco and alcohol beverages. Despite the progress of technologies of multimodal medical treatment, survival rates have not reached satisfactory levels. Over the last few decades, scientific and clinical research data have led to a growing interest in exploring potential biomarkers. In the last years, non-coding RNAs have become promising biomarkers. They are important key regulators in both normal and tumour specific biological processes as well as in the response to environmental factors and treatment, including chemo- and radiotherapy. Studies have shown ectopic expression of a number of ncRNAs in laryngeal cancer. Published data provide evidence of the lncRNAs and miRNAs that could help us better understand complex carcinogenesis in laryngeal cancer and would provide reliable diagnostic, prognostic and predictive biomarkers.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Laríngeas/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Bulgária/epidemiologia , Humanos , Incidência , Neoplasias Laríngeas/epidemiologia , Neoplasias Laríngeas/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo
5.
Cancer Epidemiol Biomarkers Prev ; 29(9): 1731-1738, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32581112

RESUMO

BACKGROUND: A polygenic hazard score (PHS), the weighted sum of 54 SNP genotypes, was previously validated for association with clinically significant prostate cancer and for improved prostate cancer screening accuracy. Here, we assess the potential impact of PHS-informed screening. METHODS: United Kingdom population incidence data (Cancer Research United Kingdom) and data from the Cluster Randomized Trial of PSA Testing for Prostate Cancer were combined to estimate age-specific clinically significant prostate cancer incidence (Gleason score ≥7, stage T3-T4, PSA ≥10, or nodal/distant metastases). Using HRs estimated from the ProtecT prostate cancer trial, age-specific incidence rates were calculated for various PHS risk percentiles. Risk-equivalent age, when someone with a given PHS percentile has prostate cancer risk equivalent to an average 50-year-old man (50-year-standard risk), was derived from PHS and incidence data. Positive predictive value (PPV) of PSA testing for clinically significant prostate cancer was calculated using PHS-adjusted age groups. RESULTS: The expected age at diagnosis of clinically significant prostate cancer differs by 19 years between the 1st and 99th PHS percentiles: men with PHS in the 1st and 99th percentiles reach the 50-year-standard risk level at ages 60 and 41, respectively. PPV of PSA was higher for men with higher PHS-adjusted age. CONCLUSIONS: PHS provides individualized estimates of risk-equivalent age for clinically significant prostate cancer. Screening initiation could be adjusted by a man's PHS. IMPACT: Personalized genetic risk assessments could inform prostate cancer screening decisions.


Assuntos
Neoplasias da Próstata/genética , Idoso , Detecção Precoce de Câncer , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Controle da População
6.
Folia Med (Plovdiv) ; 61(3): 458-461, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32337934

RESUMO

THE AIM: of the present study was to reveal the characteristics of an. MATERIALS AND METHODS: Susceptibility testing, conjugation experiments, isoelectric focusing, PCR and sequencing were carrying out. RESULTS: Of 176. CONCLUSIONS: To the best of our knowledge this is the first report of DHA-1 producing isolate in Bulgaria. The emergence of DHA-1 producing.


Assuntos
Cefalosporinase/biossíntese , Enterobacter cloacae/isolamento & purificação , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/metabolismo , Humanos , Pessoa de Meia-Idade
7.
Pathol Oncol Res ; 21(2): 413-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25149524

RESUMO

Laryngeal squamous cell carcinoma (LSCC) is the second most common tumour of the head and neck. It is characterized by frequent aberrations in two cell-cycle regulators--CDKN2A and TP53. However, LSCC has been often studied as a part of the group of head and neck cancers and not as an individual entity. In the current study we aimed to examine mutation status of CDKN2A and TP53 genes in 108 LSCC patients. DNA was extracted from fresh-frozen tumour tissues; exons 1-3 of CDKN2A and exons 5-8 of TP53 were screened for mutations by direct sequencing. Genetic aberrations in CDKN2A were found in 16 (14.2%) and those in TP53--in 56/108 (51.9%) tumours. Seven mutations (two insertions, three deletions, one missense and one silent) detected in CDKN2A were not described previously. Also, we found seven novel deletions and a novel indel in TP53. No significant associations with clinical features were found. However, TP53 mutations were predominantly observed in smokers with advanced stage tumours. Screening for genetic aberrations in a defined group of LSCC contributes to the knowledge about laryngeal carcinogenesis. Further investigations are required to confirm the observed trends in associations with clinical features.


Assuntos
Carcinoma de Células Escamosas/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias Laríngeas/genética , Mutação/genética , Proteína Supressora de Tumor p53/genética , Carcinoma de Células Escamosas/diagnóstico , DNA de Neoplasias/genética , Feminino , Genes Neoplásicos/genética , Neoplasias de Cabeça e Pescoço/genética , Humanos , Neoplasias Laríngeas/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sequência de DNA
8.
Cancer Epidemiol Biomarkers Prev ; 24(11): 1796-800, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26307654

RESUMO

BACKGROUND: Unnecessary intervention and overtreatment of indolent disease are common challenges in clinical management of prostate cancer. Improved tools to distinguish lethal from indolent disease are critical. METHODS: We performed a genome-wide survival analysis of cause-specific death in 24,023 prostate cancer patients (3,513 disease-specific deaths) from the PRACTICAL and BPC3 consortia. Top findings were assessed for replication in a Norwegian cohort (CONOR). RESULTS: We observed no significant association between genetic variants and prostate cancer survival. CONCLUSIONS: Common genetic variants with large impact on prostate cancer survival were not observed in this study. IMPACT: Future studies should be designed for identification of rare variants with large effect sizes or common variants with small effect sizes.


Assuntos
Neoplasias da Próstata/mortalidade , Estudo de Associação Genômica Ampla , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/genética , Análise de Sobrevida
9.
Cancer Epidemiol Biomarkers Prev ; 24(7): 1121-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25837820

RESUMO

BACKGROUND: Genome-wide association studies have identified multiple genetic variants associated with prostate cancer risk which explain a substantial proportion of familial relative risk. These variants can be used to stratify individuals by their risk of prostate cancer. METHODS: We genotyped 25 prostate cancer susceptibility loci in 40,414 individuals and derived a polygenic risk score (PRS). We estimated empirical odds ratios (OR) for prostate cancer associated with different risk strata defined by PRS and derived age-specific absolute risks of developing prostate cancer by PRS stratum and family history. RESULTS: The prostate cancer risk for men in the top 1% of the PRS distribution was 30.6 (95% CI, 16.4-57.3) fold compared with men in the bottom 1%, and 4.2 (95% CI, 3.2-5.5) fold compared with the median risk. The absolute risk of prostate cancer by age of 85 years was 65.8% for a man with family history in the top 1% of the PRS distribution, compared with 3.7% for a man in the bottom 1%. The PRS was only weakly correlated with serum PSA level (correlation = 0.09). CONCLUSIONS: Risk profiling can identify men at substantially increased or reduced risk of prostate cancer. The effect size, measured by OR per unit PRS, was higher in men at younger ages and in men with family history of prostate cancer. Incorporating additional newly identified loci into a PRS should improve the predictive value of risk profiles. IMPACT: We demonstrate that the risk profiling based on SNPs can identify men at substantially increased or reduced risk that could have useful implications for targeted prevention and screening programs.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias da Próstata/genética , Medição de Risco , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Variação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco
10.
Psychiatr Genet ; 14(2): 101-6, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15167697

RESUMO

Several studies provide suggestive evidence of a susceptibility locus for bipolar disorder at chromosome 21q22-23. In an attempt to replicate these findings, we have analyzed linkage to 11 polymorphic markers from this region in 18 Bulgarian pedigrees with affective disorder. Two-point linkage analysis under assumption of homogeneity and a dominant model with reduced penetrance produced modest positive values for some of the markers tested under a 'narrow' phenotype definition, including bipolar I and II, and schizoaffective disorder. The maximum two-point score (lod=1.76, theta=0.00) was at marker D21S1919. Non-parametric linkage analysis under the same phenotype model, yielded positive NPLall values (P<0.05) over the region between markers D21S211 and D21S416, with a peak at D21S1252 (NPL Zall=2.32, P=0.0003). The multipoint lod score (GENEHUNTER) reached a suggestive value for linkage (lod=2.10) also at marker D21S1252. The results under a recessive model were completely negative. These data add to the evidence for the existence of a susceptibility locus for bipolar affective disorder on chromosome 21q22.


Assuntos
Transtorno Bipolar/genética , Cromossomos Humanos Par 21/genética , Predisposição Genética para Doença/genética , Bulgária , Canadá , Mapeamento Cromossômico , Feminino , Humanos , Judeus , Escore Lod , Masculino , Modelos Genéticos , Linhagem , Estados Unidos
11.
Otol Neurotol ; 35(8): 1361-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24691507

RESUMO

OBJECTIVE: To compare the audiologic outcome after cochlear implantation between 2 groups of patients with congenital nonsyndromic sensorineural hearing loss. STUDY DESIGN: Retrospective cohort study. SETTING: Department of Otorhinolaryngology, University hospital (tertiary referral center). PATIENTS: From a bigger pool of implanted patients, 2 groups, each numbering 30 were enrolled. The patients from the first group were diagnosed with a Connexin 26 mutation (GJB2), whereas all of the patients from the second cohort were with a wild type genotype. Both groups were age matched, 1 to 7 years old at the age of implantation, with diagnosed congenital nonsyndromic sensorineural hearing loss. MAIN OUTCOME MEASURES: Both groups were evaluated with the help evaluation of auditory responses to speech/EARS/test battery - LiP test (Listening Progress Profile), MTP tests 3,6,12 (Monosyllabic-Trochee-Polysyllabic Test), GASP test (Glendonald Auditory Screening Procedure), and others. Follow-up period was at least 36 months. RESULTS: Mean test scores were compared at the 1st, 6th, 12th, 24th, and 36th month. LiP outcome was significantly better (p < 0.05) for the GJB2-related cohort for the whole follow-up period except at the first month. MTP3, 6, and 12 tests displayed the same statistically significant outcome in favor of the first group. In the open-set test GASP, the difference was apparent: 1.22, 2.40, 5.59, and 7.40 mean scores at the 6th, 12th, 24, and 36th months for the first cohort versus 0.00, 0.07, 0.81, and 1.74 for the GJB2-unrelated patients. CONCLUSION: The results from our study suggest that children with GJB2-related deafness show better auditory performance after cochlear implantation than age-matched children with GJB2-nonrelated sensorineural hearing loss.


Assuntos
Implante Coclear , Conexinas/genética , Perda Auditiva Neurossensorial/cirurgia , Criança , Pré-Escolar , Estudos de Coortes , Conexina 26 , Surdez/genética , Surdez/cirurgia , Feminino , Genótipo , Perda Auditiva Neurossensorial/genética , Humanos , Lactente , Masculino , Mutação , Estudos Retrospectivos , Resultado do Tratamento
12.
Head Neck ; 36(8): 1103-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23804521

RESUMO

BACKGROUND: Laryngeal squamous cell carcinoma (laryngeal SCC) is a frequently occurring cancer of the head and neck area. Epigenetic changes of tumor-related genes contribute to its genesis and progression. METHODS: We assessed promoter methylation status of the selected genes (CDKN2A, MGMT, MLH1, and DAPK) using methylation-sensitive high resolution melting (MS-HRM) in 100 patients with laryngeal SCC and studied the correlations with clinical characteristics. RESULTS: The prevalence of promoter methylation in MGMT, CDKN2A, MLH1, and DAPK was 59 of 97 (60.8%), 46 of 97 (47.4%), 45 of 97 (46.4%), and 41 of 97 patients (42.3%), respectively. Significantly increased methylation of CDKN2A was observed in heavy smokers. Epigenetic inactivation of CDKN2A and MLH1 were found to be associated with lymph node involvement. An inverse correlation was present between MLH1 methylation and alcohol consumption. CONCLUSION: Our results strongly suggest that deregulation of p16-associated, and MLH1-associated pathways, because of promoter hypermethylation, is associated with increased cancer cell migration, tumor invasiveness, and, thus, aggressive phenotype.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Carcinoma de Células Escamosas/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Proteínas Quinases Associadas com Morte Celular/genética , Neoplasias Laríngeas/genética , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Bulgária , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Prevalência , Regiões Promotoras Genéticas
13.
Drug Alcohol Depend ; 117(1): 62-5, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21277709

RESUMO

The µ-opioid receptor is the primary site of action of most opioids. The 118A>G (rs1799971) polymorphism in exon 1 of the µ-opioid receptor gene (OPRM1) leads to an Asn40Asp amino acid change that affects a putative N-glycosylation site. It has been widely investigated for association with alcohol and drug dependence and pain sensitivity, with mixed results. The aim of the current study was to examine whether this polymorphism was associated with heroin dependence in a large Bulgarian cohort of 1842 active users and 1451 population controls. SNP genotyping was done using Real-Time PCR TaqMan technology. Association analyses were conducted, separately for Roma and non-Roma participants. Our results suggest that there is no direct effect of 118A>G genotype on the risk for heroin dependence among active heroin users.


Assuntos
Dependência de Heroína/genética , Receptores Opioides mu/genética , Adulto , Alelos , Analgésicos Opioides/metabolismo , Bulgária/epidemiologia , Bulgária/etnologia , Estudos de Casos e Controles , Éxons , Feminino , Genótipo , Dependência de Heroína/fisiopatologia , Humanos , Masculino , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Receptores Opioides mu/fisiologia , Fatores de Risco , Romênia/etnologia
14.
DNA Cell Biol ; 28(1): 9-12, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18834326

RESUMO

Endometrial cancer (EC) is the most common malignancy of the female reproductive system in the industrialized world. Similar to other common diseases, gene variations are believed to be able to alter an individual's predisposition to developing the disease. The CHEK2 gene encodes a tumor suppressor that takes part in various cell processes, including cell cycle regulation, DNA repair, and apoptosis. The polymorphic variant Ile157Thr in exon 3 of the gene has been demonstrated to enhance the risk of several types of cancer and at the same time to reduce the risk for developing other cancer types. To study the significance of CHEK2 I157T for EC, we have genotyped 268 patients and 449 female controls. We found carriers of I157T more often among controls than we did among patients (2.45% vs. 1.75%), but the difference was not statistically significant. Case-only analysis revealed that the variant is overrepresented in patients diagnosed at 75 or more years of age (9.09%, p = 0.05) and in those with deep myometrial invasion (3.85%, p = 0.06). The highest frequency was observed in patients with both the aforementioned characteristics (20%, p = 0.01). Tumors of I157T carriers showed endometrioid, clear cell, and mucinous morphology, which suggested that the variant may not be restricted to a certain histotype of the disease and could even be overrepresented in rare ones. This study is the first to explore the association between germline CHEK2 I157T and EC. It suggests the need for further large-scale evaluation of the role this variant plays in endometrial carcinogenesis.


Assuntos
Neoplasias do Endométrio/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas Serina-Treonina Quinases/genética , Adulto , Idade de Início , Idoso , Bulgária , Quinase do Ponto de Checagem 2 , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Feminino , Genótipo , Heterozigoto , Humanos , Menopausa , Pessoa de Meia-Idade , Invasividade Neoplásica/genética
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