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Despite advancements in treatment options, the overall cure and survival rates for non-small cell lung cancers (NSCLC) remain low. While small-molecule inhibitors of epigenetic regulators have recently emerged as promising cancer therapeutics, their application in patients with NSCLC is limited. To exploit epigenetic regulators as novel therapeutic targets in NSCLC, we performed pooled epigenome-wide CRISPR knockout screens in vitro and in vivo and identified the histone chaperone nucleophosmin 1 (Npm1) as a potential therapeutic target. Genetic ablation of Npm1 significantly attenuated tumor progression in vitro and in vivo. Furthermore, KRAS-mutant cancer cells were more addicted to NPM1 expression. Genetic ablation of Npm1 rewired the balance of metabolism in cancer cells from predominant aerobic glycolysis to oxidative phosphorylation and reduced the population of tumor-propagating cells. Overall, our results support NPM1 as a therapeutic vulnerability in NSCLC. SIGNIFICANCE: Epigenome-wide CRISPR knockout screens identify NPM1 as a novel metabolic vulnerability and demonstrate that targeting NPM1 is a new therapeutic opportunity for patients with NSCLC.
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Carcinoma Pulmonar de Células não Pequenas , Técnicas Genéticas , Neoplasias Pulmonares , Proteínas Nucleares/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Epigênese Genética , Xenoenxertos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Proteínas Nucleares/genética , NucleofosminaRESUMO
Drug-tolerant "persister" tumor cells underlie emergence of drug-resistant clones and contribute to relapse and disease progression. Here we report that resistance to the BCL-2 targeting drug ABT-199 in models of mantle cell lymphoma and double-hit lymphoma evolves from outgrowth of persister clones displaying loss of 18q21 amplicons that harbor BCL2. Further, persister status is generated via adaptive super-enhancer remodeling that reprograms transcription and offers opportunities for overcoming ABT-199 resistance. Notably, pharmacoproteomic and pharmacogenomic screens revealed that persisters are vulnerable to inhibition of the transcriptional machinery and especially to inhibition of cyclin-dependent kinase 7 (CDK7), which is essential for the transcriptional reprogramming that drives and sustains ABT-199 resistance. Thus, transcription-targeting agents offer new approaches to disable drug resistance in B-cell lymphomas.
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High-grade serous ovarian cancer is characterized by extensive copy number alterations, among which the amplification of MYC oncogene occurs in nearly half of tumors. We demonstrate that ovarian cancer cells highly depend on MYC for maintaining their oncogenic growth, indicating MYC as a therapeutic target for this difficult-to-treat malignancy. However, targeting MYC directly has proven difficult. We screen small molecules targeting transcriptional and epigenetic regulation, and find that THZ1 - a chemical inhibiting CDK7, CDK12, and CDK13 - markedly downregulates MYC. Notably, abolishing MYC expression cannot be achieved by targeting CDK7 alone, but requires the combined inhibition of CDK7, CDK12, and CDK13. In 11 patient-derived xenografts models derived from heavily pre-treated ovarian cancer patients, administration of THZ1 induces significant tumor growth inhibition with concurrent abrogation of MYC expression. Our study indicates that targeting these transcriptional CDKs with agents such as THZ1 may be an effective approach for MYC-dependent ovarian malignancies.
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Antineoplásicos/metabolismo , Proteína Quinase CDC2/antagonistas & inibidores , Quinases Ciclina-Dependentes/antagonistas & inibidores , Neoplasias Ovarianas/patologia , Fenilenodiaminas/metabolismo , Proteínas Proto-Oncogênicas c-myc/biossíntese , Pirimidinas/metabolismo , Animais , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação para Baixo , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/metabolismo , Feminino , Xenoenxertos , Humanos , Camundongos SCID , Transplante de Neoplasias , Neoplasias Ovarianas/tratamento farmacológico , Fenilenodiaminas/administração & dosagem , Pirimidinas/administração & dosagem , Resultado do Tratamento , Quinase Ativadora de Quinase Dependente de CiclinaRESUMO
The addressable pocket of a protein is often not functionally relevant in disease. This is true for the multidomain, bromodomain-containing transcriptional regulator TRIM24. TRIM24 has been posited as a dependency in numerous cancers, yet potent and selective ligands for the TRIM24 bromodomain do not exert effective anti-proliferative responses. We therefore repositioned these probes as targeting features for heterobifunctional protein degraders. Recruitment of the VHL E3 ubiquitin ligase by dTRIM24 elicits potent and selective degradation of TRIM24. Using dTRIM24 to probe TRIM24 function, we characterize the dynamic genome-wide consequences of TRIM24 loss on chromatin localization and gene control. Further, we identify TRIM24 as a novel dependency in acute leukemia. Pairwise study of TRIM24 degradation versus bromodomain inhibition reveals enhanced anti-proliferative response from degradation. We offer dTRIM24 as a chemical probe of an emerging cancer dependency, and establish a path forward for numerous selective yet ineffectual ligands for proteins of therapeutic interest.
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Proteínas de Transporte/química , Células 3T3 , Animais , Linhagem Celular Tumoral , Proliferação de Células , Cristalografia por Raios X , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Leucemia Mieloide Aguda/metabolismo , Ligantes , Células MCF-7 , Camundongos , Mutagênese , Proteínas Nucleares/química , Complexo de Endopeptidases do Proteassoma/química , Ligação Proteica , Domínios Proteicos , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição/químicaRESUMO
To date, no consistent oncogenic driver mutations have been identified in most adult soft tissue sarcomas; these tumors are thus generally insensitive to existing targeted therapies. Here we investigated alternate mechanisms underlying sarcomagenesis to identify potential therapeutic interventions. Undifferentiated pleomorphic sarcoma (UPS) is an aggressive tumor frequently found in skeletal muscle where deregulation of the Hippo pathway and aberrant stabilization of its transcriptional effector yes-associated protein 1 (YAP1) increases proliferation and tumorigenesis. However, the downstream mechanisms driving this deregulation are incompletely understood. Using autochthonous mouse models and whole genome analyses, we found that YAP1 was constitutively active in some sarcomas due to epigenetic silencing of its inhibitor angiomotin (AMOT). Epigenetic modulators vorinostat and JQ1 restored AMOT expression and wild-type Hippo pathway signaling, which induced a muscle differentiation program and inhibited sarcomagenesis. YAP1 promoted sarcomagenesis by inhibiting expression of ubiquitin-specific peptidase 31 (USP31), a newly identified upstream negative regulator of NFκB signaling. Combined treatment with epigenetic modulators effectively restored USP31 expression, resulting in decreased NFκB activity. Our findings highlight a key underlying molecular mechanism in UPS and demonstrate the potential impact of an epigenetic approach to sarcoma treatment.Significance: A new link between Hippo pathway signaling, NFκB, and epigenetic reprogramming is highlighted and has the potential for therapeutic intervention in soft tissue sarcomas. Cancer Res; 78(10); 2705-20. ©2018 AACR.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Transformação Celular Neoplásica/patologia , NF-kappa B/metabolismo , Fosfoproteínas/metabolismo , Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Proteases Específicas de Ubiquitina/antagonistas & inibidores , Proteases Específicas de Ubiquitina/biossíntese , Angiomotinas , Animais , Antineoplásicos/farmacologia , Azepinas/farmacologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Via de Sinalização Hippo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Camundongos Transgênicos , Proteínas dos Microfilamentos/genética , Músculo Esquelético/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Sarcoma/genética , Transdução de Sinais/genética , Neoplasias de Tecidos Moles/genética , Fatores de Transcrição , Triazóis/farmacologia , Vorinostat/farmacologia , Proteínas de Sinalização YAPRESUMO
The release of paused RNA polymerase II into productive elongation is highly regulated, especially at genes that affect human development and disease. To exert control over this rate-limiting step, we designed sequence-specific synthetic transcription elongation factors (Syn-TEFs). These molecules are composed of programmable DNA-binding ligands flexibly tethered to a small molecule that engages the transcription elongation machinery. By limiting activity to targeted loci, Syn-TEFs convert constituent modules from broad-spectrum inhibitors of transcription into gene-specific stimulators. Here we present Syn-TEF1, a molecule that actively enables transcription across repressive GAA repeats that silence frataxin expression in Friedreich's ataxia, a terminal neurodegenerative disease with no effective therapy. The modular design of Syn-TEF1 defines a general framework for developing a class of molecules that license transcription elongation at targeted genomic loci.
Assuntos
Cromatina/metabolismo , Ataxia de Friedreich/genética , Proteínas de Ligação ao Ferro/genética , Ativação Transcricional , Fatores de Elongação da Transcrição/síntese química , Fatores de Elongação da Transcrição/metabolismo , Inativação Gênica , Humanos , RNA Polimerase II/metabolismo , Transcrição Gênica , FrataxinaRESUMO
AIM: To compare the accuracy of the nine selected algorithms for predicting warfarin dose with 586 Han Chinese patients. MATERIALS & METHODS: Genotyping of VKORC1 1639G>A, CYP2C9*2 and CYP2C9*3 variants was performed. Both the mean absolute error and ideal estimation value were used for comparison. RESULTS: The top three performers were from East Asians. The algorithms from Caucasians generally performed better in the medium-dose subgroup (>3 and <7 mg/day), while the algorithms from East Asians generally performed better in the low-dose subgroup (≤ 3 mg/day). None of the algorithms performed well in the high-dose subgroup (≥ 7 mg/day). CONCLUSION: Algorithms built for specific ethnic groups and preassigned-dose groups are suggested for better prediction.
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Algoritmos , Anticoagulantes/farmacocinética , Farmacogenética/estatística & dados numéricos , Varfarina/farmacocinética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Povo Asiático , Citocromo P-450 CYP2C9/genética , Etnicidade , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Medicina de Precisão , Reprodutibilidade dos Testes , Vitamina K Epóxido Redutases/genética , Varfarina/administração & dosagem , Varfarina/uso terapêutico , População Branca , Adulto JovemRESUMO
BACKGROUND AND OBJECTIVE: Survival of patients with pancreatic adenocarcinoma is limited and few prognostic factors are known. We conducted a two-stage genome-wide association study (GWAS) to identify germline variants associated with survival in patients with pancreatic adenocarcinoma. METHODS: We analysed overall survival in relation to single nucleotide polymorphisms (SNPs) among 1005 patients from two large GWAS datasets, PanScan I and ChinaPC. Cox proportional hazards regression was used in an additive genetic model with adjustment for age, sex, clinical stage and the top four principal components of population stratification. The first stage included 642 cases of European ancestry (PanScan), from which the top SNPs (p≤10(-5)) were advanced to a joint analysis with 363 additional patients from China (ChinaPC). RESULTS: In the first stage of cases of European descent, the top-ranked loci were at chromosomes 11p15.4, 18p11.21 and 1p36.13, tagged by rs12362504 (p=1.63×10(-7)), rs981621 (p=1.65×10(-7)) and rs16861827 (p=3.75×10(-7)), respectively. 131 SNPs with p≤10(-5) were advanced to a joint analysis with cases from the ChinaPC study. In the joint analysis, the top-ranked SNP was rs10500715 (minor allele frequency, 0.37; p=1.72×10(-7)) on chromosome 11p15.4, which is intronic to the SET binding factor 2 (SBF2) gene. The HR (95% CI) for death was 0.74 (0.66 to 0.84) in PanScan I, 0.79 (0.65 to 0.97) in ChinaPC and 0.76 (0.68 to 0.84) in the joint analysis. CONCLUSIONS: Germline genetic variation in the SBF2 locus was associated with overall survival in patients with pancreatic adenocarcinoma of European and Asian ancestry. This association should be investigated in additional large patient cohorts.
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Adenocarcinoma/genética , Biomarcadores Tumorais/genética , Estudo de Associação Genômica Ampla , Neoplasias Pancreáticas/genética , Polimorfismo de Nucleotídeo Único , Proteínas Tirosina Fosfatases não Receptoras/genética , Adenocarcinoma/etnologia , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , China , Europa (Continente) , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Neoplasias Pancreáticas/etnologia , Neoplasias Pancreáticas/mortalidade , Análise de Componente Principal , Modelos de Riscos Proporcionais , Taxa de Sobrevida , População BrancaRESUMO
Matrix metalloproteases are key regulatory molecules in the breakdown of extracellular matrix and in inflammatory processes. Matrix metalloproteinase-1 (MMP-1) can significantly enhance muscle regeneration by promoting the formation of myofibers and degenerating the fibrous tissue. Herein, we prepared novel MMP-1-loaded poly(lactide-co-glycolide-co-caprolactone) (PLGA-PCL) nanoparticles (NPs) capable of sustained release of MMP-1. We established quadratic equations as mathematical models and employed rotatable central composite design and response surface methodology to optimize the preparation procedure of the NPs. Then, characterization of the optimized NPs with respect to particle size distribution, particle morphology, drug encapsulation efficiency, MMP-1 activity assay and in vitro release of MMP-1 from NPs was carried out. The results of mathematical modeling show that the optimal conditions for the preparation of MMP-1-loaded NPs were as follows: 7 min for the duration time of homogenization, 4.5 krpm for the agitation speed of homogenization and 0.4 for the volume ratio of organic solvent phase to external aqueous phase. The entrapment efficiency and the average particle size of the NPs were 38.75 ± 4.74% and 322.7 ± 18.1 nm, respectively. Further scanning electron microscopy image shows that the NPs have a smooth and spherical surface, with mean particle size around 300 nm. The MMP-1 activity assay and in vitro drug release profile of NPs indicated that the bioactivity of the enzyme can be reserved where the encapsulation allows prolonged release of MMP-1 over 60 days. Taken together, we reported here novel PLGA-PCL NPs for sustained release of MMP-1, which may provide an ideal MMP-1 delivery approach for tissue reconstruction therapy.
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ABO blood type has been associated with risk and survival for several malignancies; however, data for an association with breast cancer are inconsistent. Our study population consisted of Nurses' Health Study participants with self-reported serologic blood type and/or ABO genotype. Using Cox proportional hazards regression, we examined the association between serologic blood type and incident breast cancer among 67,697 women, including 3,107 cases. In addition, we examined the association with ABO genotype in a nested case-control study of 1,138 invasive breast cancer cases and 1,090 matched controls. Finally, we evaluated the association between serologic blood type and survival among 2,036 participants with breast cancer. No clear association was seen between serologic blood type or ABO genotype and risk of total breast cancer, invasive breast cancer or breast cancer subtypes. Compared to women with blood type O, the age-adjusted incidence rate ratios for serologic blood type and total breast cancer were 1.06 (95% CI, 0.98-1.15) for type A, 1.06 (95% CI, 0.93-1.22) for AB and 1.08 (95% CI, 0.96-1.20) for B. In genetic analyses, odds ratios for invasive breast cancer were 1.05 (95% CI, 0.87-1.27) for A/O, 1.21 (95% CI, 0.86-1.69) for A/A, 0.84 (95% CI, 0.56-1.26) for A/B, 0.84 (95% CI, 0.63-1.13) for B/O and 1.17 (95% CI, 0.35-3.86) for B/B, compared to O/O. No significant association was noted between blood type and overall or breast cancer-specific mortality. Our results suggest no association between ABO blood group and breast cancer risk or survival.
Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Neoplasias da Mama/sangue , Neoplasias da Mama/epidemiologia , Adulto , Idoso , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Fatores de RiscoRESUMO
BACKGROUND: Recently, a pathway-based approach has been developed to evaluate the cumulative contribution of the functionally related genes for genome-wide association studies (GWASs), which may help utilize GWAS data to a greater extent. METHODS: In this study, we applied this approach for the GWAS of basal cell carcinoma (BCC) of the skin. We first conducted the BCC GWAS among 1,797 BCC cases and 5,197 controls in Caucasians with 740,760 genotyped SNPs. 115,688 SNPs were grouped into gene transcripts within 20 kb in distance and then into 174 Kyoto Encyclopedia of Genes and Genomes pathways, 205 BioCarta pathways, as well as two positive control gene sets (pigmentation gene set and BCC risk gene set). The association of each pathway with BCC risk was evaluated using the weighted Kolmogorov-Smirnov test. One thousand permutations were conducted to assess the significance. RESULTS: Both of the positive control gene sets reached pathway p-values<0.05. Four other pathways were also significantly associated with BCC risk: the heparan sulfate biosynthesis pathway (p â=â 0.007, false discovery rate, FDR â=â 0.35), the mCalpain pathway (p â=â 0.002, FDR â=â 0.12), the Rho cell motility signaling pathway (p â=â 0.011, FDR â=â 0.30), and the nitric oxide pathway (p â=â 0.022, FDR â=â 0.42). CONCLUSION: We identified four pathways associated with BCC risk, which may offer new insights into the etiology of BCC upon further validation, and this approach may help identify potential biological pathways that might be missed by the standard GWAS approach.
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Carcinoma Basocelular/genética , Genoma Humano , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , Transdução de Sinais , Neoplasias Cutâneas/genética , Estudos de Casos e Controles , Humanos , Fenótipo , Fatores de RiscoRESUMO
BACKGROUND: Personalized health-care promises tailored health-care solutions to individual patients based on their genetic background and/or environmental exposure history. To date, disease prediction has been based on a few environmental factors and/or single nucleotide polymorphisms (SNPs), while complex diseases are usually affected by many genetic and environmental factors with each factor contributing a small portion to the outcome. We hypothesized that the use of random forests classifiers to select SNPs would result in an improved predictive model of asthma exacerbations. We tested this hypothesis in a population of childhood asthmatics. METHODS: In this study, using emergency room visits or hospitalizations as the definition of a severe asthma exacerbation, we first identified a list of top Genome Wide Association Study (GWAS) SNPs ranked by Random Forests (RF) importance score for the CAMP (Childhood Asthma Management Program) population of 127 exacerbation cases and 290 non-exacerbation controls. We predict severe asthma exacerbations using the top 10 to 320 SNPs together with age, sex, pre-bronchodilator FEV1 percentage predicted, and treatment group. RESULTS: Testing in an independent set of the CAMP population shows that severe asthma exacerbations can be predicted with an Area Under the Curve (AUC)=0.66 with 160-320 SNPs in comparison to an AUC score of 0.57 with 10 SNPs. Using the clinical traits alone yielded AUC score of 0.54, suggesting the phenotype is affected by genetic as well as environmental factors. CONCLUSIONS: Our study shows that a random forests algorithm can effectively extract and use the information contained in a small number of samples. Random forests, and other machine learning tools, can be used with GWAS studies to integrate large numbers of predictors simultaneously.
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Inteligência Artificial , Asma/diagnóstico , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Algoritmos , Área Sob a Curva , Asma/genética , Criança , Humanos , Valor Preditivo dos TestesRESUMO
We conducted a genome-wide association study on cutaneous basal cell carcinoma (BCC) among 2045 cases and 6013 controls of European ancestry, with follow-up replication in 1426 cases and 4845 controls. A non-synonymous SNP in the MC1R gene (rs1805007 encoding Arg151Cys substitution), a previously well-documented pigmentation gene, showed the strongest association with BCC risk in the discovery set (rs1805007[T]: OR (95% CI) for combined discovery set and replication set [1.55 (1.45-1.66); P= 4.3 × 10(-17)]. We identified that an SNP rs12210050 at 6p25 near the EXOC2 gene was associated with an increased risk of BCC [rs12210050[T]: combined OR (95% CI), 1.24 (1.17-1.31); P= 9.9 × 10(-10)]. In the locus on 13q32 near the UBAC2 gene encoding ubiquitin-associated domain-containing protein 2, we also identified a variant conferring susceptibility to BCC [rs7335046 [G]; combined OR (95% CI), 1.26 (1.18-1.34); P= 2.9 × 10(-8)]. We further evaluated the associations of these two novel SNPs (rs12210050 and rs7335046) with squamous cell carcinoma (SCC) risk as well as melanoma risk. We found that both variants, rs12210050[T] [OR (95% CI), 1.35 (1.16-1.57); P= 7.6 × 10(-5)] and rs7335046 [G] [OR (95% CI), 1.21 (1.02-1.44); P= 0.03], were associated with an increased risk of SCC. These two variants were not associated with melanoma risk. We conclude that 6p25 and 13q32 are novel loci conferring susceptibility to non-melanoma skin cancer.
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Carcinoma Basocelular/genética , Carcinoma de Células Escamosas/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Cutâneas/genética , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , População Branca/genética , Adulto JovemRESUMO
We conducted a genome-wide association study on the number of melanocytic nevi reported by 9136 individuals of European ancestry, with follow-up replication in 3581 individuals. We identified the nidogen 1 (NID1) gene on 1q42 associated with nevus count (two linked single nucleotide polymorphisms with r(2) > 0.9: rs3768080 A allele associated with reduced count, P = 6.5 × 10(-8); and rs10754833 T allele associated with reduced count, P = 1.5 × 10(-7)). We further determined that the rs10754833 [T] was associated with a decreased melanoma risk in 2368 melanoma cases and 7432 controls [for CT genotype: odds ratio (OR) = 0.86, 95% confidence interval (CI) = 0.75-0.99, P = 0.04; for TT genotype: OR = 0.84, 95% CI = 0.71-0.98, P = 0.03]. Expression level of the NID1 locus was 2-fold higher for the rs10754833 T allele carriers than that with the CC genotype (P = 0.017) in the 87 HapMap CEU cell lines. The NID1 gene is a biologically plausible locus for nevogenesis and melanoma development, with decreased expression levels of NID1 in benign nevi (P = 3.5 × 10(-6)) and in primary melanoma (P = 4.6 × 10(-4)) compared with the normal skin.
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Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Melanoma/genética , Glicoproteínas de Membrana/genética , Nevo Pigmentado/genética , Risco , Neoplasias Cutâneas/genética , Adulto , Idoso , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
BACKGROUND: Subjects with non-O ABO blood group alleles have increased risk of pancreatic cancer. Glycosyltransferase activity is greater for the A(1) versus A(2) variant, whereas O01 and O02 variants are nonfunctioning. We hypothesized: 1) A(1) allele would confer greater risk than A(2) allele, 2) protective effect of the O allele would be equivalent for O01 and O02 variants, 3) secretor phenotype would modify the association with risk. METHODS: We determined ABO variants and secretor phenotype from single nucleotide polymorphisms in ABO and FUT2 genes in 1,533 cases and 1,582 controls from 12 prospective cohort studies. Adjusted odds ratios (OR) for pancreatic cancer were calculated using logistic regression. RESULTS: An increased risk was observed in participants with A(1) but not A(2) alleles. Compared with subjects with genotype O/O, genotypes A(2)/O, A(2)/A(1), A(1)/O, and A(1)/A(1) had ORs of 0.96 (95% CI, 0.72-1.26), 1.46 (95% CI, 0.98-2.17), 1.48 (95% CI, 1.23-1.78), and 1.71 (95% CI, 1.18-2.47). Risk was similar for O01 and O02 variant O alleles. Compared with O01/O01, the ORs for each additional allele of O02, A(1), and A(2) were 1.00 (95% CI, 0.87-1.14), 1.38 (95% CI, 1.20-1.58), and 0.96 (95% CI, 0.77-1.20); P, O01 versus O02 = 0.94, A(1) versus A(2) = 0.004. Secretor phenotype was not an effect modifier (P-interaction = 0.63). CONCLUSIONS: Among participants in a large prospective cohort consortium, ABO allele subtypes corresponding to increased glycosyltransferase activity were associated with increased pancreatic cancer risk. IMPACT: These data support the hypothesis that ABO glycosyltransferase activity influences pancreatic cancer risk rather than actions of other nearby genes on chromosome 9q34.
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Sistema ABO de Grupos Sanguíneos/genética , Predisposição Genética para Doença , Neoplasias Pancreáticas/genética , Alelos , Estudos de Coortes , Estudo de Associação Genômica Ampla , Genótipo , Glicosiltransferases/genética , Humanos , Razão de Chances , Fenótipo , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Genome-wide association studies of human gene expression promise to identify functional regulatory genetic variation that contributes to phenotypic diversity. However, it is unclear how useful this approach will be for the identification of disease-susceptibility variants. We generated gene expression profiles for 22 184 mRNA transcripts using RNA derived from peripheral blood CD4+ lymphocytes, and genome-wide genotype data for 516 512 autosomal markers in 200 subjects. We screened for cis-acting variants by testing variants mapping within 50 kb of expressed transcripts for association with transcript abundance using generalized linear models. Significant associations were identified for 1585 genes at a false discovery rate of 0.05 (corresponding to P-values ranging from 1 × 10(-91) to 7 × 10(-4)). Importantly, we identified evidence of regulatory variation for 119 previously mapped disease genes, including 24 examples where the variant with the strongest evidence of disease-association demonstrates strong association with specific transcript abundance. The prevalence of cis-acting variants among disease-associated genes was 63% higher than the genome-wide rate in our data set (P = 6.41 × 10(-6)), and although many of the implicated loci were associated with immune-related diseases (including asthma, connective tissue disorders and inflammatory bowel disease), associations with genes implicated in non-immune-related diseases including lipid profiles, anthropomorphic measurements, cancer and neurologic disease were also observed. Genetic variants that confer inter-individual differences in gene expression represent an important subset of variants that contribute to disease susceptibility. Population-based integrative genetic approaches can help identify such variation and enhance our understanding of the genetic basis of complex traits.
Assuntos
Linfócitos T CD4-Positivos , Marcadores Genéticos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Asma/genética , Expressão Gênica , Perfilação da Expressão Gênica , Teste de Complementação Genética , Doenças Genéticas Inatas , Predisposição Genética para Doença , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Fenótipo , Característica Quantitativa Herdável , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Alveolarization depends on circulating glucocorticoid (GC), retinoid (RA), and vitamin D (VitD). Bronchopulmonary dysplasia, a leading cause of neonatal morbidity, is associated with arrested alveolarization. In hyperoxia-exposed rats displaying features of bronchopulmonary dysplasia, reduced levels of late gestation lung 1 (Lgl1) normalize during recovery. We show that GC (100 nM) stimulates (7- to 115-fold) and VitD (100 microM) suppresses (twofold) Lgl1 expression. RA (all-trans/9-cis, 10 microM) effects are biphasic. From postnatal days 7-10, RA was stimulatory (twofold) at 24 h, after which effects were inhibitory (3- to 15-fold). Lgl1 promoter-luciferase reporter assays confirmed that these agents operated at the transcriptional level. Interestingly, the individual inhibitory effects of VitD and RA on GC induction of Lgl1 were abrogated when both agents were present, suggesting that steric hindrance may influence promoter accessibility. Analysis of the proximity (<50 base pairs) of binding sites for overlapping VitD and RA receptors to that of the GC receptor identified 81% of promoters in 66 genes (including Lgl1) important in human lung development compared with 48% in a random set of 1000 genes. Complex integration of the effects of GC, RA, and VitD on gene expression in the postnatal lung is likely to contribute to the timely advance of alveolarization without attendant inflammation.
Assuntos
Antineoplásicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas/metabolismo , Alvéolos Pulmonares/fisiologia , Esteroides/farmacologia , Tretinoína/farmacologia , Vitamina D/farmacologia , Animais , Sítios de Ligação , Linhagem Celular , Feminino , Fibroblastos/citologia , Fibroblastos/fisiologia , Humanos , Gravidez , Regiões Promotoras Genéticas , Proteínas/genética , Alvéolos Pulmonares/citologia , Ratos , Ratos Sprague-Dawley , Transcrição GênicaRESUMO
Expression QTL mapping by integrating genome-wide gene expression and genotype data is a promising approach to identifying functional genetic variation, but is hampered by the large number of multiple comparisons inherent in such studies. A novel approach to addressing multiple testing problems in genome-wide family-based association studies is screening candidate markers using heritability or conditional power. We apply these methods in settings in which microarray gene expression data are used as phenotypes, screening for SNPs near the expressed genes. We perform association analyses for phenotypes using a univariate approach. We also perform simulations on trios with large numbers of causal SNPs to determine the optimal number of markers to use in a screen. We demonstrate that our family-based screening approach performs well in the analysis of integrative genomic datasets and that screening using either heritability or conditional power produces similar, though not identical, results.