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1.
Nat Commun ; 14(1): 8081, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057307

RESUMO

In high-income countries, mosaic chromosomal alterations in peripheral blood leukocytes are associated with an elevated risk of adverse health outcomes, including hematologic malignancies. We investigate mosaic chromosomal alterations in sub-Saharan Africa among 931 children with Burkitt lymphoma, an aggressive lymphoma commonly characterized by immunoglobulin-MYC chromosomal rearrangements, 3822 Burkitt lymphoma-free children, and 674 cancer-free men from Ghana. We find autosomal and X chromosome mosaic chromosomal alterations in 3.4% and 1.7% of Burkitt lymphoma-free children, and 8.4% and 3.7% of children with Burkitt lymphoma (P-values = 5.7×10-11 and 3.74×10-2, respectively). Autosomal mosaic chromosomal alterations are detected in 14.0% of Ghanaian men and increase with age. Mosaic chromosomal alterations in Burkitt lymphoma cases include gains on chromosomes 1q and 8, the latter spanning MYC, while mosaic chromosomal alterations in Burkitt lymphoma-free children include copy-neutral loss of heterozygosity on chromosomes 10, 14, and 16. Our results highlight mosaic chromosomal alterations in sub-Saharan African populations as a promising area of research.


Assuntos
Linfoma de Burkitt , Masculino , Criança , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Gana , Aberrações Cromossômicas , Leucócitos/patologia , Imunoglobulinas/genética , Translocação Genética
2.
Nat Commun ; 14(1): 4322, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468456

RESUMO

The association between fatty acids and prostate cancer remains poorly explored in African-descent populations. Here, we analyze 24 circulating fatty acids in 2934 men, including 1431 prostate cancer cases and 1503 population controls from Ghana and the United States, using CLIA-certified mass spectrometry-based assays. We investigate their associations with population groups (Ghanaian, African American, European American men), lifestyle factors, the fatty acid desaturase (FADS) genetic locus, and prostate cancer. Blood levels of circulating fatty acids vary significantly between the three population groups, particularly trans, omega-3 and omega-6 fatty acids. FADS1/2 germline genetic variants and lifestyle factors explain some of the variation in fatty acid levels, with the FADS1/2 locus showing population-specific associations, suggesting differences in their control by germline genetic factors. All trans fatty acids, namely elaidic, palmitelaidic, and linoelaidic acids, associated with an increase in the odds of developing prostate cancer, independent of ancestry, geographic location, or potential confounders.


Assuntos
Ácidos Graxos Ômega-3 , Neoplasias da Próstata , Ácidos Graxos trans , Masculino , Humanos , Estados Unidos/epidemiologia , Gana/epidemiologia , Ácidos Graxos Dessaturases/genética , Ácidos Graxos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética , Polimorfismo de Nucleotídeo Único
3.
Eur Urol ; 84(1): 13-21, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36872133

RESUMO

BACKGROUND: Genetic factors play an important role in prostate cancer (PCa) susceptibility. OBJECTIVE: To discover common genetic variants contributing to the risk of PCa in men of African ancestry. DESIGN, SETTING, AND PARTICIPANTS: We conducted a meta-analysis of ten genome-wide association studies consisting of 19378 cases and 61620 controls of African ancestry. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Common genotyped and imputed variants were tested for their association with PCa risk. Novel susceptibility loci were identified and incorporated into a multiancestry polygenic risk score (PRS). The PRS was evaluated for associations with PCa risk and disease aggressiveness. RESULTS AND LIMITATIONS: Nine novel susceptibility loci for PCa were identified, of which seven were only found or substantially more common in men of African ancestry, including an African-specific stop-gain variant in the prostate-specific gene anoctamin 7 (ANO7). A multiancestry PRS of 278 risk variants conferred strong associations with PCa risk in African ancestry studies (odds ratios [ORs] >3 and >5 for men in the top PRS decile and percentile, respectively). More importantly, compared with men in the 40-60% PRS category, men in the top PRS decile had a significantly higher risk of aggressive PCa (OR = 1.23, 95% confidence interval = 1.10-1.38, p = 4.4 × 10-4). CONCLUSIONS: This study demonstrates the importance of large-scale genetic studies in men of African ancestry for a better understanding of PCa susceptibility in this high-risk population and suggests a potential clinical utility of PRS in differentiating between the risks of developing aggressive and nonaggressive disease in men of African ancestry. PATIENT SUMMARY: In this large genetic study in men of African ancestry, we discovered nine novel prostate cancer (PCa) risk variants. We also showed that a multiancestry polygenic risk score was effective in stratifying PCa risk, and was able to differentiate risk of aggressive and nonaggressive disease.


Assuntos
Predisposição Genética para Doença , Neoplasias da Próstata , Masculino , Humanos , Estudo de Associação Genômica Ampla , Neoplasias da Próstata/genética , Neoplasias da Próstata/epidemiologia , Fatores de Risco , População Negra/genética
4.
Nat Commun ; 13(1): 1759, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365620

RESUMO

There is evidence that tumor immunobiology and immunotherapy response may differ between African American and European American prostate cancer patients. Here, we determine if men of African descent harbor a unique systemic immune-oncological signature and measure 82 circulating proteins in almost 3000 Ghanaian, African American, and European American men. Protein signatures for suppression of tumor immunity and chemotaxis are elevated in men of West African ancestry. Importantly, the suppression of tumor immunity protein signature associates with metastatic and lethal prostate cancer, pointing to clinical importance. Moreover, two markers, pleiotrophin and TNFRSF9, predict poor disease survival specifically among African American men. These findings indicate that immune-oncology marker profiles differ between men of African and European descent. These differences may contribute to the disproportionate burden of lethal prostate cancer in men of African ancestry. The elevated peripheral suppression of tumor immunity may have important implication for guidance of cancer therapy which could particularly benefit African American patients.


Assuntos
Neoplasias da Próstata , Proteômica , Negro ou Afro-Americano , População Negra/genética , Gana , Humanos , Masculino , Neoplasias da Próstata/patologia
5.
Int J Cancer ; 147(10): 2669-2676, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32350862

RESUMO

Obesity has been associated with an increased risk of advanced prostate cancer. However, most studies have been conducted among North American and European populations. Prostate cancer mortality appears elevated in West Africa, yet risk factors for prostate cancer in this region are unknown. We thus examined the relationship between obesity and prostate cancer using a case-control study conducted in Accra, Ghana in 2004 to 2012. Cases and controls were drawn from a population-based sample of 1037 men screened for prostate cancer, yielding 73 cases and 964 controls. An additional 493 incident cases were recruited from the Korle-Bu Teaching Hospital. Anthropometric measurements were taken at enrollment. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR) and prostate cancer, adjusting for potential confounders. The mean BMI was 25.1 kg/m2 for cases and 24.3 kg/m2 for controls. After adjustment, men with BMI ≥ 30 kg/m2 had an increased risk of prostate cancer relative to men with BMI < 25 kg/m2 (OR 1.86, 95% CI 1.11-3.13). Elevated WC (OR 1.76, 95% CI 1.24-2.51) and WHR (OR 1.46, 95% CI 0.99-2.16) were also associated with prostate cancer. Associations were not modified by smoking status and were evident for low- and high-grade disease. These findings indicate that overall and abdominal obesity are positively associated with prostate cancer among men in Ghana, implicating obesity as a potentially modifiable risk factor for prostate cancer in this region.


Assuntos
Obesidade Abdominal/epidemiologia , Neoplasias da Próstata/epidemiologia , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Gana/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias da Próstata/patologia , Circunferência da Cintura , Relação Cintura-Quadril
6.
JCO Glob Oncol ; 6: 610-616, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32302237

RESUMO

PURPOSE: In a review of cancer incidence across continents (GLOBOCAN 2012), data sources from Ghana were classified as Frequencies, the lowest classification for inclusion, signifying the worst data quality for inclusion in the analysis. Recognizing this deficiency, the establishment of a population-based cancer registry was proposed as part of a broader cancer control plan. METHODS: The registry was examined under the following headings: policy, data source, and administrative structure; external support and training; and definition of geographic coverage. RESULTS: The registry was set up based on the Ghana policy document on the strategy for cancer control. The paradigm shift ensured subscription to one data collection software (CanReg 5) in the country. The current approach consists of trained registrars based in the registry who conduct active data abstraction at the departments and units of the hospital and pathologic services. To ensure good governance, an administrative structure was created, including an advisory board, a technical committee, and registry staff. External support for the establishment of the Accra Cancer Registry has come mainly from Stanford University and the African Cancer Registry Network, in collaboration with the University of Ghana. Unlike previous attempts, this registry has a well-defined population made up of nine municipal districts. CONCLUSION: The Accra Cancer Registry was established as a result of the lessons learned from failed previous attempts and aim to provide a model for setting up other cancer registries in Ghana. It will eventually be the focal point where all the national data can be collated.


Assuntos
Atenção à Saúde , Neoplasias , Sistema de Registros , Países em Desenvolvimento , Gana/epidemiologia , Humanos , Incidência , Neoplasias/epidemiologia
7.
PLoS Genet ; 15(3): e1008027, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30849090

RESUMO

Populations in sub-Saharan Africa have historically been exposed to intense selection from chronic infection with falciparum malaria. Interestingly, populations with the highest malaria intensity can be identified by the increased occurrence of endemic Burkitt Lymphoma (eBL), a pediatric cancer that affects populations with intense malaria exposure, in the so called "eBL belt" in sub-Saharan Africa. However, the effects of intense malaria exposure and sub-Saharan populations' genetic histories remain poorly explored. To determine if historical migrations and intense malaria exposure have shaped the genetic composition of the eBL belt populations, we genotyped ~4.3 million SNPs in 1,708 individuals from Ghana and Northern Uganda, located on opposite sides of eBL belt and with ≥ 7 months/year of intense malaria exposure and published evidence of high incidence of BL. Among 35 Ghanaian tribes, we showed a predominantly West-Central African ancestry and genomic footprints of gene flow from Gambian and East African populations. In Uganda, the North West population showed a predominantly Nilotic ancestry, and the North Central population was a mixture of Nilotic and Southern Bantu ancestry, while the Southwest Ugandan population showed a predominant Southern Bantu ancestry. Our results support the hypothesis of diverse ancestral origins of the Ugandan, Kenyan and Tanzanian Great Lakes African populations, reflecting a confluence of Nilotic, Cushitic and Bantu migrations in the last 3000 years. Natural selection analyses suggest, for the first time, a strong positive selection signal in the ATP2B4 gene (rs10900588) in Northern Ugandan populations. These findings provide important baseline genomic data to facilitate disease association studies, including of eBL, in eBL belt populations.


Assuntos
Linfoma de Burkitt/genética , Fluxo Gênico , Malária Falciparum/genética , Seleção Genética , Adolescente , África Subsaariana , Idoso , Linfoma de Burkitt/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Doenças Endêmicas , Feminino , Genética Populacional , Estudo de Associação Genômica Ampla , Gana/epidemiologia , Migração Humana , Humanos , Incidência , Lactente , Recém-Nascido , Malária Falciparum/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Polimorfismo de Nucleotídeo Único , Uganda/epidemiologia
8.
Occup Environ Med ; 76(2): 71-77, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30530485

RESUMO

OBJECTIVES: Established prostate cancer (PCa) risk factors include age, family history of PCa and African ancestry. Studies, mostly among highly screened, predominantly European ancestral populations, suggest that employment in certain occupations (eg, farming, military) may also have an increased risk for PCa. Here, we evaluated the association between usual adult occupation and PCa risk in Ghanaian men, a population with historically low rates of PCa screening. METHODS: The Ghana Prostate Study is a case-control study of PCa that was conducted from 2004 to 2012 in 749 cases and 964 controls. In-person interviews were conducted to collect information from participants, including longest held job. Industrial hygienists classified job titles into occupational categories. Unconditional logistic regression was used to calculate ORs and 95% CIs for the association between longest held job and PCa risk (overall, aggressive (Gleason≥7)), controlling for potential confounders. RESULTS: Risk was increased among men in management (overall PCa OR=2.2, 95% CI 1.4 to 3.2; aggressive PCa OR=2.2, 95% CI 1.3 to 3.5) and military occupations (overall PCa OR=3.4, 95% CI 1.7 to 7.0; aggressive PCa OR=3.5, 95% CI 1.5 to 8.3). Risks were also elevated for management and military-specific jobs based on 3-digit level Standard Occupational Classification definitions. Sensitivity analyses accounting for access to medical care did not show significant differences. CONCLUSIONS: Our study provides some evidence for increased risk of PCa among men in management and military occupations, which is consistent with the published literature. Additional research is needed to clarify the drivers of the associations between these occupations and PCa.


Assuntos
Ocupações/estatística & dados numéricos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/etiologia , Idoso , Estudos de Casos e Controles , Gana/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Militares , Gestão de Recursos Humanos , Fatores de Risco
9.
J Natl Cancer Inst ; 109(8)2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29117387

RESUMO

Prostate cancer incidence is 1.6-fold higher in African Americans than in other populations. The risk factors that drive this disparity are unknown and potentially consist of social, environmental, and genetic influences. To investigate the genetic basis of prostate cancer in men of African ancestry, we performed a genome-wide association meta-analysis using two-sided statistical tests in 10 202 case subjects and 10 810 control subjects. We identified novel signals on chromosomes 13q34 and 22q12, with the risk-associated alleles found only in men of African ancestry (13q34: rs75823044, risk allele frequency = 2.2%, odds ratio [OR] = 1.55, 95% confidence interval [CI] = 1.37 to 1.76, P = 6.10 × 10-12; 22q12.1: rs78554043, risk allele frequency = 1.5%, OR = 1.62, 95% CI = 1.39 to 1.89, P = 7.50 × 10-10). At 13q34, the signal is located 5' of the gene IRS2 and 3' of a long noncoding RNA, while at 22q12 the candidate functional allele is a missense variant in the CHEK2 gene. These findings provide further support for the role of ancestry-specific germline variation in contributing to population differences in prostate cancer risk.


Assuntos
População Negra/genética , Loci Gênicos , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/genética , Estudos de Casos e Controles , Quinase do Ponto de Checagem 2/genética , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 22 , Frequência do Gene , Estudo de Associação Genômica Ampla , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Masculino
10.
Am J Epidemiol ; 186(12): 1352-1361, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28633309

RESUMO

The prevalence of fusions of the transmembrane protease, serine 2, gene (TMPRSS2) with the erythroblast transformation-specific-related gene (ERG), or TMPRSS2:ERG, in prostate cancer varies by race. However, such somatic aberration and its association with prognostic factors have neither been studied in a West African population nor been systematically reviewed in the context of racial differences. We used immunohistochemistry to assess oncoprotein encoded by the ERG gene as the established surrogate of ERG fusion genes among 262 prostate cancer biopsies from the Ghana Prostate Study (2004-2006). Poisson regression with robust variance estimation provided prevalence ratios and 95% confidence intervals of ERG expression in relation to patient characteristics. We found that 47 of 262 (18%) prostate cancers were ERG-positive, and being negative for ERG staining was associated with higher Gleason score. We further conducted a systematic review and meta-analysis of TMPRSS2:ERG fusions in relation to race, Gleason score, and tumor stage, combining results from Ghana with 40 additional studies. Meta-analysis showed the prevalence of TMPRSS2:ERG fusions in prostate cancer to be highest in men of European descent (49%), followed by men of Asian (27%) and then African (25%) descent. The lower prevalence of TMPRSS2:ERG fusions in men of African descent implies that alternative genomic mechanisms might explain the disproportionately high prostate cancer burden in such populations.


Assuntos
Fusão Gênica , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/genética , Serina Endopeptidases/genética , Idoso , Comorbidade , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prevalência , Neoplasias da Próstata/patologia , Grupos Raciais/estatística & dados numéricos , Regulador Transcricional ERG/genética
11.
Nat Commun ; 7: 10979, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27052111

RESUMO

Although genome-wide association studies have identified over 100 risk loci that explain ∼33% of familial risk for prostate cancer (PrCa), their functional effects on risk remain largely unknown. Here we use genotype data from 59,089 men of European and African American ancestries combined with cell-type-specific epigenetic data to build a genomic atlas of single-nucleotide polymorphism (SNP) heritability in PrCa. We find significant differences in heritability between variants in prostate-relevant epigenetic marks defined in normal versus tumour tissue as well as between tissue and cell lines. The majority of SNP heritability lies in regions marked by H3k27 acetylation in prostate adenoc7arcinoma cell line (LNCaP) or by DNaseI hypersensitive sites in cancer cell lines. We find a high degree of similarity between European and African American ancestries suggesting a similar genetic architecture from common variation underlying PrCa risk. Our findings showcase the power of integrating functional annotation with genetic data to understand the genetic basis of PrCa.


Assuntos
Negro ou Afro-Americano , Epigênese Genética , Predisposição Genética para Doença , Padrões de Herança , Neoplasias da Próstata/genética , População Branca , Acetilação , Atlas como Assunto , Linhagem Celular Tumoral , Loci Gênicos , Estudo de Associação Genômica Ampla , Histonas/genética , Histonas/metabolismo , Humanos , Desequilíbrio de Ligação , Masculino , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/patologia
12.
J Natl Cancer Inst ; 108(7)2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26823525

RESUMO

The 8q24 region harbors multiple risk variants for distinct cancers, including >8 for prostate cancer. In this study, we conducted fine mapping of the 8q24 risk region (127.8-128.8Mb) in search of novel associations with common and rare variation in 4853 prostate cancer case patients and 4678 control subjects of African ancestry. All statistical tests were two-sided. We identified three independent associations at P values of less than 5.00×10(-8), all of which were replicated in studies from Ghana and Uganda (combined sample = 5869 case patients, 5615 control subjects; rs114798100: risk allele frequency [RAF] = 0.04, per-allele odds ratio [OR] = 2.31, 95% confidence interval [CI] = 2.04 to 2.61, P = 2.38×10(-40); rs72725879: RAF = 0.33, OR = 1.37, 95% CI = 1.30 to 1.45, P = 3.04×10(-27); and rs111906932: RAF = 0.03, OR = 1.79, 95% CI = 1.53 to 2.08, P = 1.39×10(-13)). Risk variants rs114798100 and rs111906923 are only found in men of African ancestry, with rs111906923 representing a novel association signal. The three variants are located within or near a number of prostate cancer-associated long noncoding RNAs (lncRNAs), including PRNCR1, PCAT1, and PCAT2. These findings highlight ancestry-specific risk variation and implicate prostate-specific lncRNAs at the 8q24 prostate cancer susceptibility region.


Assuntos
Negro ou Afro-Americano/genética , Cromossomos Humanos Par 8 , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , RNA Longo não Codificante/genética , Estados Unidos/epidemiologia
13.
Breast J ; 21(6): 627-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26547900

RESUMO

Breast cancers that have negative or extremely low expression of estrogen receptor and progesterone receptor and non-amplification of human epidermal growth factor receptor-2 (HER2)/neu are termed triple-negative breast cancer (TNBC). The majority of TNBC tumors belong to the biologically aggressive basal subtype, and they cannot be managed with targeted endocrine or anti-HER2/neu agents. In western, high resource environments, risk factors for TNBC include younger age at diagnosis and hereditary susceptibility. Women of African ancestry in the United States and in continental Africa have higher frequencies of TNBC, prompting speculation that this risk may have an inherited basis and may at least partially explain breast cancer survival disparities related to racial/ethnic identity. Efforts to document and confirm the breast cancer burden of continental Africa have been hampered by the limited availability of registry and immunohistochemistry resources. Our goal was to evaluate the breast cancers diagnosed in one of the largest health care facilities in western Africa, and to compare the frequencies as well as risk factors for TNBC versus non-TNBC in this large referral tertiary hospital. The Korle Bu Teaching Hospital is affiliated with the University of Ghana and is located in Accra, the capital of Ghana. We conducted an institutional, Department of Pathology-based review of the breast cancer cases seen at this facility for the 2010 calendar year, and for which histopathologic specimens were available. The overall study population of 223 breast cancer cases had a median age of 52.4 years, and most had palpable tumors larger than 5 cm in diameter. More than half were TNBC (130; 58.3%). We observed similar age-specific frequencies, distribution of stage at diagnosis and tumor grade among cases of TNBC compared to cases of non-TNBC. Ghanaian breast cancer patients tend to have an advanced stage distribution and relatively younger age at diagnosis compared to Caucasian Americans and African Americans. The triple-negative molecular marker pattern was the most common subtype of breast cancer seen among this sample of Ghanaian women, regardless of age, tumor grade, or stage of diagnosis. Research into the molecular pathogenesis of TNBC may help elucidate the reasons for its increased prevalence among women with African ancestry.


Assuntos
Carcinoma Ductal de Mama/secundário , Hospitais de Ensino , Neoplasias de Mama Triplo Negativas/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/etnologia , Feminino , Gana , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Neoplasias de Mama Triplo Negativas/química , Neoplasias de Mama Triplo Negativas/etnologia , Carga Tumoral
14.
Hum Mol Genet ; 24(19): 5603-18, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26162851

RESUMO

Interpretation of biological mechanisms underlying genetic risk associations for prostate cancer is complicated by the relatively large number of risk variants (n = 100) and the thousands of surrogate SNPs in linkage disequilibrium. Here, we combined three distinct approaches: multiethnic fine-mapping, putative functional annotation (based upon epigenetic data and genome-encoded features), and expression quantitative trait loci (eQTL) analyses, in an attempt to reduce this complexity. We examined 67 risk regions using genotyping and imputation-based fine-mapping in populations of European (cases/controls: 8600/6946), African (cases/controls: 5327/5136), Japanese (cases/controls: 2563/4391) and Latino (cases/controls: 1034/1046) ancestry. Markers at 55 regions passed a region-specific significance threshold (P-value cutoff range: 3.9 × 10(-4)-5.6 × 10(-3)) and in 30 regions we identified markers that were more significantly associated with risk than the previously reported variants in the multiethnic sample. Novel secondary signals (P < 5.0 × 10(-6)) were also detected in two regions (rs13062436/3q21 and rs17181170/3p12). Among 666 variants in the 55 regions with P-values within one order of magnitude of the most-associated marker, 193 variants (29%) in 48 regions overlapped with epigenetic or other putative functional marks. In 11 of the 55 regions, cis-eQTLs were detected with nearby genes. For 12 of the 55 regions (22%), the most significant region-specific, prostate-cancer associated variant represented the strongest candidate functional variant based on our annotations; the number of regions increased to 20 (36%) and 27 (49%) when examining the 2 and 3 most significantly associated variants in each region, respectively. These results have prioritized subsets of candidate variants for downstream functional evaluation.


Assuntos
Povo Asiático/genética , População Negra/genética , Hispânico ou Latino/genética , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/genética , População Branca/genética , Mapeamento Cromossômico/métodos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Anotação de Sequência Molecular , Neoplasias da Próstata/etnologia , Locos de Características Quantitativas
15.
Prostate ; 74(6): 579-89, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24783269

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have identified that a ∼1 M region centromeric to the MYC oncogene on chromosome 8q24.21 harbors at least five independent loci associated with prostate cancer risk and additional loci associated with cancers of breast, colon, bladder, and chronic lymphocytic leukemia (CLL). Because GWAS identify genetic markers that may be indirectly associated with disease, fine-mapping based on sequence analysis provides important insights into patterns of linkage disequilibrium (LD) and is critical in defining the optimal variants to nominate for biological follow-up. METHODS: To catalog variation in individuals of African ancestry, we resequenced a region (250 kb; chr8:128,050, 768­128, 300,801, hg19) containing several prostate cancer susceptibility loci as well as a locus associated with CLL. Our samples included 78 individuals from Ghana and 47 of African-Americans from Johns Hopkins University. RESULTS: After quality control metrics were applied to next-generation sequence data, 1,838 SNPs were identified. Of these, 285 were novel and not yet reported in any public database. Using genotypes derived from sequencing, we refined the LD and recombination hotspots within the region and determined a set of tag SNPs to be used in future fine-mapping studies. Based on LD, we annotated putative risk loci and their surrogates using ENCODE data, which should help guide laboratory studies. CONCLUSIONS: In comparison to the 1000 Genome Project data, we have identified additional variants that could be important in establishing priorities for future functional work designed to explain the biological basis of associations between SNPs and both prostate cancer and CLL.


Assuntos
População Negra/genética , Cromossomos Humanos Par 8 , Predisposição Genética para Doença , Neoplasias da Próstata/genética , Frequência do Gene , Loci Gênicos , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Polimorfismo de Nucleotídeo Único
16.
J Urol ; 192(3): 730-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24747091

RESUMO

PURPOSE: To our knowledge the reasons for the high rates of prostate cancer in black American men are unknown. Genetic and lifestyle factors have been implicated. Better understanding of prostate cancer rates in West African men would help clarify why black American men have such high rates since the groups share genetic ancestry and yet have different lifestyles and screening practices. To estimate the prostate cancer burden in West African men we performed a population based screening study with biopsy confirmation in Ghana. MATERIALS AND METHODS: We randomly selected 1,037 healthy men 50 to 74 years old from Accra, Ghana for prostate cancer screening with prostate specific antigen testing and digital rectal examination. Men with a positive screen result (positive digital rectal examination or prostate specific antigen greater than 2.5 ng/ml) underwent transrectal ultrasound guided biopsies. RESULTS: Of the 1,037 men 154 (14.9%) had a positive digital rectal examination and 272 (26.2%) had prostate specific antigen greater than 2.5 ng/ml, including 166 with prostate specific antigen greater than 4.0 ng/ml. A total of 352 men (33.9%) had a positive screen by prostate specific antigen or digital rectal examination and 307 (87%) underwent biopsy. Of these men 73 were confirmed to have prostate cancer, yielding a 7.0% screen detected prostate cancer prevalence (65 patients), including 5.8% with prostate specific antigen greater than 4.0 ng/ml. CONCLUSIONS: In this relatively unscreened population in Africa the screen detected prostate cancer prevalence is high, suggesting a possible role of genetics in prostate cancer etiology and the disparity in prostate cancer risk between black and white American men. Further studies are needed to confirm the high prostate cancer burden in African men and the role of genetics in prostate cancer etiology.


Assuntos
População Negra , Neoplasias da Próstata/epidemiologia , Negro ou Afro-Americano , Idoso , Gana , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Antígeno Prostático Específico
17.
Hum Genet ; 133(5): 509-21, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24185611

RESUMO

Age-adjusted mortality rates for prostate cancer are higher for African-American men compared with those of European ancestry. Recent data suggest that West African men also have elevated risk for prostate cancer relative to European men. Genetic susceptibility to prostate cancer could account for part of this difference. We conducted a genome-wide association study (GWAS) of prostate cancer in West African men in the Ghana Prostate Study. Association testing was performed using multivariable logistic regression adjusted for age and genetic ancestry for 474 prostate cancer cases and 458 population-based controls on the Illumina HumanOmni-5 Quad BeadChip. The most promising association was at 10p14 within an intron of a long non-coding RNA (lncRNA RP11-543F8.2) 360 kb centromeric of GATA3 (p = 1.29E-7). In sub-analyses, SNPs at 5q31.3 were associated with high Gleason score (≥7) cancers, the strongest of which was a missense SNP in PCDHA1 (rs34575154, p = 3.66E-8), and SNPs at Xq28 (rs985081, p = 8.66E-9) and 6q21 (rs2185710, p = 5.95E-8) were associated with low Gleason score (<7) cancers. We sought to validate our findings in silico in the African Ancestry Prostate Cancer GWAS Consortium, but only one SNP, at 10p14, replicated at p < 0.05. Of the 90 prostate cancer loci reported from studies of men of European, Asian or African-American ancestry, we were able to test 81 in the Ghana Prostate Study, and 10 of these replicated at p < 0.05. Further genetic studies of prostate cancer in West African men are needed to confirm our promising susceptibility loci.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias da Próstata/genética , África Ocidental , Idoso , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade
18.
Am J Clin Pathol ; 140(1): 97-102, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23765539

RESUMO

OBJECTIVES: To evaluate breast cancer in Ghanaian women and to compare these findings with those of previous studies by using histopathologic data. METHODS: A review of all breast cancer specimens from January 2005 through December 2009 in our institution was conducted. RESULTS: Of 4,109 female breast specimens reviewed, 1,342 (32.7%) were malignant. Mean (SD) patient age was 50.3 (13.3) years, and mean size of the primary tumors was 4.5 cm. Eighteen (1.3%) specimens were malignant phyllodes tumors. Significant positive associations were found between size of the primary tumor and histologic type (P = .01), histologic grade (P = .001), nodal involvement (P < .001), and TNM stage (P < .001). CONCLUSIONS: More than 3 decades after the first publication of breast cancer in Ghanaian women, patients are still presenting with large clinically and histologically advanced invasive cancers.


Assuntos
Neoplasias da Mama/epidemiologia , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Lobular/epidemiologia , Tumor Filoide/epidemiologia , Sarcoma/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Coleta de Dados , Feminino , Gana/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Tumor Filoide/patologia , Sarcoma/patologia , Adulto Jovem
19.
BMC Res Notes ; 4: 353, 2011 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-21910900

RESUMO

BACKGROUND: There is limited data on adolescent mortality particularly from developing countries with unreliable death registration systems. This calls for the use of other sources of data to ascertain cause of adolescent mortality. The objective of this study was to describe the causes of death among Ghanaian adolescents 10 to 19 years in Accra, Ghana utilizing data from autopsies conducted in Korle Bu Teaching Hospital (KBTH). FINDINGS: Out of the 14,034 autopsies carried out from 2001 to 2003 in KBTH, 7% were among adolescents. Of the 882 deaths among adolescents analyzed, 402 (45.6%) were females. There were 365 (41.4%) deaths from communicable disease, pregnancy related conditions and nutritional disorders. Non-communicable diseases accounted for 362 (41%) cases and the rest were attributable to injuries and external causes of morbidity and mortality. Intestinal infectious diseases and lower respiratory tract infections were the most common communicable causes of death collectively accounting for 20.5% of total deaths. Death from blood diseases was the largest (8.5%) among the non-communicable conditions followed by neoplasms (7%). Males were more susceptible to injuries than females (χ2 = 13.45, p = .000). At least five out of ten specific causes of death were as a result of infections with pneumonia and typhoid being the most common. Sickle cell disease was among the top three specific causes of death. Among the females, 27 deaths (6.7%) were pregnancy related with most of them being as a result of abortion. CONCLUSIONS: The autopsy data from the Korle-Bu Teaching Hospital can serve as a useful source of information on adolescent mortality. Both communicable and non-communicable diseases accounted for most deaths highlighting the need for health care providers to avoid complacency in their management of adolescents presenting with these diseases.

20.
Am J Hematol ; 86(7): 554-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21674575

RESUMO

Chronic antigenic stimulation is associated with hypergamma-globulinemia. Higher rates of hypergamma-globulinemia in tropical populations are maintained even with migration to temperate regions. We conducted a population-based screening study to assess the prevalence and risk factors for hypergamma-globulinemia in Ghana, Africa. 917 Ghanaian males (50-74 years) underwent in-person interviews and health examinations. Serum from all persons was analyzed by electrophoresis performed on agarose gel; serum with a discrete/localized band was subjected to immunofixation. 54 persons with monoclonal proteins were excluded and 17 samples were insufficient for analysis. Using logistic regression and Chi-square statistics we analyzed patterns of hypergamma-globulinemia. Among 846 study subjects, the median γ-globulin level was 1.86 g/dL. On the basis of a U.S. reference, 616 (73%) had hypergamma-globulinemia (>1.6 g/dL) and 178 (21%) had γ-globulin levels >2.17 gm/dl. On multivariate analyses, lower education status (P = 0.0013) and never smoking (P = 0.038) were associated with increased γ-globulin levels. Self-reported history of syphilis was associated with hypergamma-globulinemia. We conclude that three quarters of this population-based adult Ghanaian male sample had hypergamma-globulinemia with γ-globulin levels >1.6 g/dL. Future studies are needed to uncover genetic and environmental underpinnings of our finding, and to define the relationship between hypergamma-globulinemia, monoclonal gammopathy of undetermined significance (MGUS), and multiple myeloma.


Assuntos
Hipergamaglobulinemia/sangue , Hipergamaglobulinemia/epidemiologia , Imunoglobulina G/sangue , Adulto , Idoso , Gana/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada
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