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1.
bioRxiv ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38293167

RESUMO

Androgenetic alopecia is a highly heritable trait. However, much of our understanding about the genetics of male pattern baldness comes from individuals of European descent. Here, we examined a novel dataset comprising 2,136 men from Ghana, Nigeria, Senegal, and South Africa that were genotyped using a custom array. We first tested how genetic predictions of baldness generalize from Europe to Africa, finding that polygenic scores from European GWAS yielded AUC statistics that ranged from 0.513 to 0.546, indicating that genetic predictions of baldness in African populations performed notably worse than in European populations. Subsequently, we conducted the first African GWAS of androgenetic alopecia, focusing on self-reported baldness patterns at age 45. After correcting for present age, population structure, and study site, we identified 266 moderately significant associations, 51 of which were independent (p-value < 10-5, r2 < 0.2). Most baldness associations were autosomal, and the X chromosomes does not appear to have a large impact on baldness in African men. Finally, we examined the evolutionary causes of continental differences in genetic architecture. Although Neanderthal alleles have previously been associated with skin and hair phenotypes, we did not find evidence that European-ascertained baldness hits were enriched for signatures of ancient introgression. Most loci that are associated with androgenetic alopecia are evolving neutrally. However, multiple baldness-associated SNPs near the EDA2R and AR genes have large allele frequency differences between continents. Collectively, our findings illustrate how evolutionary history contributes to the limited portability of genetic predictions across ancestries.

2.
medRxiv ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37961155

RESUMO

We conducted a multi-ancestry genome-wide association study of prostate-specific antigen (PSA) levels in 296,754 men (211,342 European ancestry; 58,236 African ancestry; 23,546 Hispanic/Latino; 3,630 Asian ancestry; 96.5% of participants were from the Million Veteran Program). We identified 318 independent genome-wide significant (p≤5e-8) variants, 184 of which were novel. Most demonstrated evidence of replication in an independent cohort (n=95,768). Meta-analyzing discovery and replication (n=392,522) identified 447 variants, of which a further 111 were novel. Out-of-sample variance in PSA explained by our new polygenic risk score reached 16.9% (95% CI=16.1%-17.8%) in European ancestry, 9.5% (95% CI=7.0%-12.2%) in African ancestry, 18.6% (95% CI=15.8%-21.4%) in Hispanic/Latino, and 15.3% (95% CI=12.7%-18.1%) in Asian ancestry, and lower for higher age. Our study highlights how including proportionally more participants from underrepresented populations improves genetic prediction of PSA levels, with potential to personalize prostate cancer screening.

3.
Dis Markers ; 2022: 1686991, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246565

RESUMO

Introduction: Prostate cancer is one of the most commonly diagnosed cancers in men. Prostate-specific antigen (PSA) has been the biomarker of choice for screening and diagnosis of prostate cancer. However, inefficiencies exist with its diagnostic capabilities. This study thus evaluated the diagnostic and prognostic potential of urinary PCA3 as an alternative biomarker for prostate cancer in the Ghanaian population. Methods: A hospital-based cross-sectional study was conducted at the Urology Department of the 37 Military Hospital, Accra, Ghana. A total of 237 participants aged 40 years and above with any form of suspected prostate disorder were recruited into the study after written informed consent was obtained. Total serum PSA levels was measured using the electrochemiluminescence method and transrectal ultrasound-guided systematic core needle biopsies were obtained from each study participant. Receiver operating characteristic curve (ROC) analysis was used to evaluate the diagnostic accuracies of serum PSA, DRE, and PCA3 as diagnostic tools for prostate cancer. These three diagnostic tools were also evaluated in various combinations to ascertain the combinations with the best diagnostic accuracy. Results: Prostate cancer was diagnosed in 26.6% of the participants. Benign prostate hyperplasia and prostatitis were diagnosed in 48.5% and 24.9% participants, respectively. DRE had a sensitivity of 93.7% and a specificity of 12.1%. PSA had a sensitivity of 92.1% and a specificity of 16.1%. PCA3 had a sensitivity of 57.1% and a specificity of 85.6% and showed a better accuracy (AUC = 83.0) compared to PSA (AUC = 60.0) and DRE (AUC = 65.0) as individual diagnostic tools. The combination of DRE+PCA3 score had the best diagnostic accuracy (AUC = 0.80) with a sensitivity and specificity of 60.3% and 80.5%, respectively. Conclusion: The urinary PCA3 assay showed a better diagnostic performance compared to serum PSA and DRE. PCA3 as a stand-alone and in combination with DRE could be a suitable complimentary marker in diagnosis and management of prostate cancer.


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Humanos , Masculino , Antígenos de Neoplasias , Biomarcadores Tumorais , Biópsia , Estudos Transversais , Gana , Próstata/patologia , Neoplasias da Próstata/patologia
4.
Genome Biol ; 23(1): 194, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100952

RESUMO

BACKGROUND: Genome-wide association studies do not always replicate well across populations, limiting the generalizability of polygenic risk scores (PRS). Despite higher incidence and mortality rates of prostate cancer in men of African descent, much of what is known about cancer genetics comes from populations of European descent. To understand how well genetic predictions perform in different populations, we evaluated test characteristics of PRS from three previous studies using data from the UK Biobank and a novel dataset of 1298 prostate cancer cases and 1333 controls from Ghana, Nigeria, Senegal, and South Africa. RESULTS: Allele frequency differences cause predicted risks of prostate cancer to vary across populations. However, natural selection is not the primary driver of these differences. Comparing continental datasets, we find that polygenic predictions of case vs. control status are more effective for European individuals (AUC 0.608-0.707, OR 2.37-5.71) than for African individuals (AUC 0.502-0.585, OR 0.95-2.01). Furthermore, PRS that leverage information from African Americans yield modest AUC and odds ratio improvements for sub-Saharan African individuals. These improvements were larger for West Africans than for South Africans. Finally, we find that existing PRS are largely unable to predict whether African individuals develop aggressive forms of prostate cancer, as specified by higher tumor stages or Gleason scores. CONCLUSIONS: Genetic predictions of prostate cancer perform poorly if the study sample does not match the ancestry of the original GWAS. PRS built from European GWAS may be inadequate for application in non-European populations and perpetuate existing health disparities.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias da Próstata , África Subsaariana/epidemiologia , Predisposição Genética para Doença , Humanos , Masculino , Neoplasias da Próstata/genética , Fatores de Risco
5.
Elife ; 112022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35801699

RESUMO

Background: We recently developed a multi-ancestry polygenic risk score (PRS) that effectively stratifies prostate cancer risk across populations. In this study, we validated the performance of the PRS in the multi-ancestry Million Veteran Program and additional independent studies. Methods: Within each ancestry population, the association of PRS with prostate cancer risk was evaluated separately in each case-control study and then combined in a fixed-effects inverse-variance-weighted meta-analysis. We further assessed the effect modification by age and estimated the age-specific absolute risk of prostate cancer for each ancestry population. Results: The PRS was evaluated in 31,925 cases and 490,507 controls, including men from European (22,049 cases, 414,249 controls), African (8794 cases, 55,657 controls), and Hispanic (1082 cases, 20,601 controls) populations. Comparing men in the top decile (90-100% of the PRS) to the average 40-60% PRS category, the prostate cancer odds ratio (OR) was 3.8-fold in European ancestry men (95% CI = 3.62-3.96), 2.8-fold in African ancestry men (95% CI = 2.59-3.03), and 3.2-fold in Hispanic men (95% CI = 2.64-3.92). The PRS did not discriminate risk of aggressive versus nonaggressive prostate cancer. However, the OR diminished with advancing age (European ancestry men in the top decile: ≤55 years, OR = 7.11; 55-60 years, OR = 4.26; >70 years, OR = 2.79). Men in the top PRS decile reached 5% absolute prostate cancer risk ~10 years younger than men in the 40-60% PRS category. Conclusions: Our findings validate the multi-ancestry PRS as an effective prostate cancer risk stratification tool across populations. A clinical study of PRS is warranted to determine whether the PRS could be used for risk-stratified screening and early detection. Funding: This work was supported by the National Cancer Institute at the National Institutes of Health (grant numbers U19 CA214253 to C.A.H., U01 CA257328 to C.A.H., U19 CA148537 to C.A.H., R01 CA165862 to C.A.H., K99 CA246063 to B.F.D, and T32CA229110 to F.C), the Prostate Cancer Foundation (grants 21YOUN11 to B.F.D. and 20CHAS03 to C.A.H.), the Achievement Rewards for College Scientists Foundation Los Angeles Founder Chapter to B.F.D, and the Million Veteran Program-MVP017. This research has been conducted using the UK Biobank Resource under application number 42195. This research is based on data from the Million Veteran Program, Office of Research and Development, and the Veterans Health Administration. This publication does not represent the views of the Department of Veteran Affairs or the United States Government.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias da Próstata , Fatores Etários , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética , Fatores de Risco , Estados Unidos/epidemiologia
6.
Cancer Causes Control ; 33(2): 223-239, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34783926

RESUMO

PURPOSE: African men are disproportionately affected by prostate cancer (PCa). Given the increasing prevalence of obesity in Africa, and its association with aggressive PCa in other populations, we examined the relationship of overall and central obesity with risks of total and aggressive PCa among African men. METHODS: Between 2016 and 2020, we recruited 2,200 PCa cases and 1,985 age-matched controls into a multi-center, hospital-based case-control study in Senegal, Ghana, Nigeria, and South Africa. Participants completed an epidemiologic questionnaire, and anthropometric factors were measured at clinic visit. Multivariable logistic regression was used to examine associations of overall and central obesity with PCa risk, measured by body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR), respectively. RESULTS: Among controls 16.4% were obese (BMI ≥ 30 kg/m2), 26% and 90% had WC > 97 cm and WHR > 0.9, respectively. Cases with aggressive PCa had lower BMI/obesity in comparison to both controls and cases with less aggressive PCa, suggesting weight loss related to cancer. Overall obesity (odds ratio: OR = 1.38, 95% CI 0.99-1.93), and central obesity (WC > 97 cm: OR = 1.60, 95% CI 1.10-2.33; and WHtR > 0.59: OR = 1.68, 95% CI 1.24-2.29) were positively associated with D'Amico intermediate-risk PCa, but not with risks of total or high-risk PCa. Associations were more pronounced in West versus South Africa, but these differences were not statistically significant. DISCUSSION: The high prevalence of overall and central obesity in African men and their association with intermediate-risk PCa represent an emerging public health concern in Africa. Large cohort studies are needed to better clarify the role of obesity and PCa in various African populations.


Assuntos
Obesidade Abdominal , Neoplasias da Próstata , Índice de Massa Corporal , Estudos de Casos e Controles , Humanos , Masculino , Obesidade/complicações , Obesidade/epidemiologia , Obesidade Abdominal/complicações , Obesidade Abdominal/epidemiologia , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/etiologia , Fatores de Risco , Circunferência da Cintura , Relação Cintura-Quadril
7.
Pan Afr Med J ; 36: 251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014247

RESUMO

INTRODUCTION: there is a high incidence of prostate cancer among men of African descent. The disease tends to occur at an early age with a tendency to be aggressive. The objective was to determine the practice of urologists in the West African sub-region regarding treatment of localized prostate cancer, the use of nomograms and their perception of the usefulness of nomograms. METHODS: this was a cross-sectional study that involved urologists practicing in the West African sub-region attending urology and surgery conferences of the "Société Internationale d´Urologie", West African college of surgeons and the Ghana association of urological surgeons. A structured questionnaire was used that sort to ascertain the treatment modalities used for localized prostate cancer and the use of nomograms in the sub-region. The study period spanned the years 2018 and 2019. RESULTS: fifty-six urologists practicing in eleven West African countries responded. Fifty percent had been in practice for less than 5 years. Sixty eight percent (38/56) had been involved in the treatment of localized prostate cancer. Radical prostatectomy was widely available and the treatment modality most used 94.7% (36/38). Nomograms was used by 57.9% of them (22/38) with the Partin tables being the most commonly used nomogram (34.2%). No Locally developed nomogram for treatment of localized prostate cancer was identified. CONCLUSION: radical prostatectomy is the commonest treatment modality used for the management of localized prostate cancer in the West Africa sub-region. Majority of the urologists used nomograms with the Partin tables being the most used.


Assuntos
Nomogramas , Prostatectomia/estatística & dados numéricos , Neoplasias da Próstata/terapia , Urologistas/estatística & dados numéricos , África Ocidental , Estudos Transversais , Humanos , Masculino , Inquéritos e Questionários
8.
Cancer Res ; 80(13): 2956-2966, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32393663

RESUMO

Although prostate cancer is the leading cause of cancer mortality for African men, the vast majority of known disease associations have been detected in European study cohorts. Furthermore, most genome-wide association studies have used genotyping arrays that are hindered by SNP ascertainment bias. To overcome these disparities in genomic medicine, the Men of African Descent and Carcinoma of the Prostate (MADCaP) Network has developed a genotyping array that is optimized for African populations. The MADCaP Array contains more than 1.5 million markers and an imputation backbone that successfully tags over 94% of common genetic variants in African populations. This array also has a high density of markers in genomic regions associated with cancer susceptibility, including 8q24. We assessed the effectiveness of the MADCaP Array by genotyping 399 prostate cancer cases and 403 controls from seven urban study sites in sub-Saharan Africa. Samples from Ghana and Nigeria clustered together, whereas samples from Senegal and South Africa yielded distinct ancestry clusters. Using the MADCaP array, we identified cancer-associated loci that have large allele frequency differences across African populations. Polygenic risk scores for prostate cancer were higher in Nigeria than in Senegal. In summary, individual and population-level differences in prostate cancer risk were revealed using a novel genotyping array. SIGNIFICANCE: This study presents an Africa-specific genotyping array, which enables investigators to identify novel disease associations and to fine-map genetic loci that are associated with prostate and other cancers.


Assuntos
População Negra/genética , Predisposição Genética para Doença , Neoplasias/epidemiologia , Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética , Estudos de Casos e Controles , Estudos de Coortes , Loci Gênicos , Genética Populacional , Estudo de Associação Genômica Ampla , Humanos , Masculino , Neoplasias/classificação , Neoplasias da Próstata/classificação , Fatores de Risco , África do Sul/epidemiologia
9.
Ghana Med J ; 53(4): 304-307, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32116343

RESUMO

OBJECTIVE: The purpose of this study was to determine the indications and complications of intracorporeal lithotripsy in our institution. METHODS: Retrospective study carried out at the urology unit of the 37 Military Hospital between 2012-2015. 42 patients had intracorporeal lithotripsy out of 359 patients who had surgery within the period. Records of all patients who had intracorporeal lithotripsy between December 2012 to December 2015 were collected and analysed. An endourology log sheet was used to record data of patient's name, age, sex, indication for operation, location of stone, intraoperative complications, type of instruments/materials used, stone analysis and follow-up dates. All patients between the ages of six months to seventy years presenting with urinary stones diseases within the period were included, whilst patients with urinary stone disease who were managed with open surgery were excluded.Ethical clearance was obtained from the 37 Military Hospital institutional review board. RESULTS: Lithotripsy constituted 42/359(11.7%) of the methods used in the surgical cases done within the period.The commonest age of presentation was between 31-40 years (26.2%), with a male to female ratio of 2:1. The commonest indications for lithotripsy were pain (92.8%) and hydronephrosis (61.9%). Ureteric stones are more common (50%), followed by renal stones (45%) with the commonest site being the proximal ureter. The commonest procedure was ureteroscopy. Ureteral mucosal injury (5/43) (11.62%), was the commonest intraoperative complication. Postoperative complications were reno-cutaneous fistula (1/43) (2.32%), severe bleeding (1/43) (2.32%) haematuria (4/43) (9.30%). CONCLUSION: Pain was the commonest indication for intra-corporeal lithotripsy (92.8%) and also the commonest post-operative complication (9.30%). FUNDING: None declared.


Assuntos
Fístula Cutânea/etiologia , Cálculos Renais/terapia , Litotripsia/efeitos adversos , Hemorragia Pós-Operatória/etiologia , Cálculos Ureterais/terapia , Fístula Urinária/etiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Gana , Hematúria/etiologia , Hospitais Militares , Humanos , Hidronefrose/etiologia , Lactente , Complicações Intraoperatórias/etiologia , Cálculos Renais/complicações , Masculino , Pessoa de Meia-Idade , Mucosa/lesões , Dor/etiologia , Seleção de Pacientes , Estudos Retrospectivos , Ferida Cirúrgica/etiologia , Ureter/lesões , Cálculos Ureterais/complicações , Ureteroscopia/efeitos adversos , Adulto Jovem
10.
J Glob Oncol ; 4: 1-12, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30260756

RESUMO

PURPOSE: Health research in low- and middle-income countries can generate novel scientific knowledge and improve clinical care, fostering population health improvements to prevent premature death. Project management is a critical part of the success of this research, applying knowledge, skills, tools, and techniques to accomplish required goals. Here, we describe the development and implementation of tools to support a multifaceted study of prostate cancer in Africa, focusing on building strategic and operational capacity. METHODS: Applying a learning organizational framework, we developed and implemented a project management toolkit (PMT) that includes a management process flowchart, a cyclical center-specific schedule of activities, periodic reporting and communication, and center-specific monitoring and evaluation metrics. RESULTS: The PMT was successfully deployed during year one of the project with effective component implementation occurring through periodic cycles of dissemination and feedback to local center project managers. A specific evaluation was conducted 1 year after study initiation to obtain enrollment data, evaluate individual quality control management plans, and undertake risk log assessments and follow-up. Pilot data obtained identified areas in which centers required mentoring, strengthening, and capacity development. Strategies were implemented to improve project goals and operational capacity through local problem solving, conducting quality control checks and following compliancy with study aims. Moving forward, centers will perform quarterly evaluations and initiate strengthening measures as required. CONCLUSION: The PMT has fostered the development of both strategic and operational capacity across project centers. Investment in project management resources is essential to ensuring high-quality, impactful health research in low- and middle-income countries.


Assuntos
Carcinoma/epidemiologia , Neoplasias da Próstata/epidemiologia , População Negra , Carcinoma/patologia , Países em Desenvolvimento , Humanos , Renda , Masculino , Próstata/patologia , Neoplasias da Próstata/patologia , África do Sul/epidemiologia
11.
J Glob Oncol ; 4: 1-14, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30260755

RESUMO

PURPOSE: Cancer of the prostate (CaP) is the leading cancer among men in sub-Saharan Africa (SSA). A substantial proportion of these men with CaP are diagnosed at late (usually incurable) stages, yet little is known about the etiology of CaP in SSA. METHODS: We established the Men of African Descent and Carcinoma of the Prostate Network, which includes seven SSA centers partnering with five US centers to study the genetics and epidemiology of CaP in SSA. We developed common data elements and instruments, regulatory infrastructure, and biosample collection, processing, and shipping protocols. We tested this infrastructure by collecting epidemiologic, medical record, and genomic data from a total of 311 patients with CaP and 218 matched controls recruited at the seven SSA centers. We extracted genomic DNA from whole blood, buffy coat, or buccal swabs from 265 participants and shipped it to the Center for Inherited Disease Research (Baltimore, MD) and the Centre for Proteomics and Genomics Research (Cape Town, South Africa), where genotypes were generated using the UK Biobank Axiom Array. RESULTS: We used common instruments for data collection and entered data into the shared database. Double-entered data from pilot participants showed a 95% to 98% concordance rate, suggesting that data can be collected, entered, and stored with a high degree of accuracy. Genotypes were obtained from 95% of tested DNA samples (100% from blood-derived DNA samples) with high concordance across laboratories. CONCLUSION: We provide approaches that can produce high-quality epidemiologic and genomic data in multicenter studies of cancer in SSA.


Assuntos
Carcinoma/epidemiologia , Carcinoma/genética , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética , Baltimore , População Negra , Carcinoma/patologia , Genômica , Genótipo , Humanos , Masculino , Próstata/patologia , Neoplasias da Próstata/patologia , África do Sul/epidemiologia
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