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1.
PLoS Genet ; 15(3): e1008027, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30849090

RESUMEN

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.


Asunto(s)
Linfoma de Burkitt/genética , Flujo Génico , Malaria Falciparum/genética , Selección Genética , Adolescente , África del Sur del Sahara , Anciano , Linfoma de Burkitt/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Enfermedades Endémicas , Femenino , Genética de Población , Estudio de Asociación del Genoma Completo , Ghana/epidemiología , Migración Humana , Humanos , Incidencia , Lactante , Recién Nacido , Malaria Falciparum/epidemiología , Masculino , Persona de Mediana Edad , Modelos Genéticos , ATPasas Transportadoras de Calcio de la Membrana Plasmática/genética , Polimorfismo de Nucleótido Simple , Uganda/epidemiología
2.
Int J Cancer ; 147(10): 2669-2676, 2020 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-32350862

RESUMEN

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.


Asunto(s)
Obesidad Abdominal/epidemiología , Neoplasias de la Próstata/epidemiología , Anciano , Índice de Masa Corporal , Estudios de Casos y Controles , Ghana/epidemiología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Neoplasias de la Próstata/patología , Circunferencia de la Cintura , Relación Cintura-Cadera
3.
Occup Environ Med ; 76(2): 71-77, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30530485

RESUMEN

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.


Asunto(s)
Ocupaciones/estadística & datos numéricos , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/etiología , Anciano , Estudios de Casos y Controles , Ghana/epidemiología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Personal Militar , Administración de Personal , Factores de Riesgo
4.
Am J Epidemiol ; 186(12): 1352-1361, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28633309

RESUMEN

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.


Asunto(s)
Fusión Génica , Neoplasias de la Próstata/etnología , Neoplasias de la Próstata/genética , Serina Endopeptidasas/genética , Anciano , Comorbilidad , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Prevalencia , Neoplasias de la Próstata/patología , Grupos Raciales/estadística & datos numéricos , Regulador Transcripcional ERG/genética
5.
Hum Mol Genet ; 24(19): 5603-18, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26162851

RESUMEN

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.


Asunto(s)
Pueblo Asiatico/genética , Población Negra/genética , Hispánicos o Latinos/genética , Polimorfismo de Nucleótido Simple , Neoplasias de la Próstata/genética , Población Blanca/genética , Mapeo Cromosómico/métodos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Desequilibrio de Ligamiento , Masculino , Anotación de Secuencia Molecular , Neoplasias de la Próstata/etnología , Sitios de Carácter Cuantitativo
6.
Breast J ; 21(6): 627-33, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26547900

RESUMEN

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.


Asunto(s)
Carcinoma Ductal de Mama/secundario , Hospitales de Enseñanza , Neoplasias de la Mama Triple Negativas/patología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/etnología , Femenino , Ghana , Humanos , Metástasis Linfática , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Receptor ErbB-2/análisis , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Neoplasias de la Mama Triple Negativas/química , Neoplasias de la Mama Triple Negativas/etnología , Carga Tumoral
7.
Prostate ; 74(6): 579-89, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24783269

RESUMEN

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.


Asunto(s)
Población Negra/genética , Cromosomas Humanos Par 8 , Predisposición Genética a la Enfermedad , Neoplasias de la Próstata/genética , Frecuencia de los Genes , Sitios Genéticos , Estudio de Asociación del Genoma Completo , Genotipo , Haplotipos , Humanos , Desequilibrio de Ligamiento , Masculino , Polimorfismo de Nucleótido Simple
8.
Hum Genet ; 133(5): 509-21, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24185611

RESUMEN

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.


Asunto(s)
Estudio de Asociación del Genoma Completo , Neoplasias de la Próstata/genética , África Occidental , Anciano , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad
9.
J Urol ; 192(3): 730-5, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24747091

RESUMEN

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.


Asunto(s)
Población Negra , Neoplasias de la Próstata/epidemiología , Negro o Afroamericano , Anciano , Ghana , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Antígeno Prostático Específico
10.
JCO Glob Oncol ; 10: e2300403, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38870437

RESUMEN

PURPOSE: Prostate cancer disproportionately affects men of African descent, yet their representation in tissue-based studies is limited. This multinational, multicenter pilot study aims to establish the groundwork for collaborative research on prostate cancer in sub-Saharan Africa. METHODS: The Men of African Descent and Carcinoma of the Prostate network formed a pathologist working group representing eight institutions in five African countries. Formalin-fixed paraffin-embedded prostate tissue specimens were collected from Senegal, Nigeria, and Ghana. Histology slides were produced and digitally scanned. A central genitourinary pathologist (P.L.) and eight African general pathologists reviewed anonymized digital whole-slide images for International Society of Urological Pathology grade groups and other pathologic parameters. Discrepancies were re-evaluated, and consensus grading was assigned. A virtual training seminar on prostate cancer grading was followed by a second assessment on a subcohort of the same tissue set. RESULTS: Of 134 tissue blocks, 133 had evaluable tissue; 13 lacked cancer evidence, and four were of insufficient quality. Post-training, interobserver agreement for grade groups improved to 56%, with a median Cohen's quadratic weighted kappa of 0.83 (mean, 0.74), compared with an initial 46% agreement and a quadratic weighted kappa of 0.77. Interobserver agreement between African pathologist groups was 40%, with a quadratic weighted kappa of 0.66 (95% CI, 0.51 to 0.76). African pathologists tended to overgrade (36%) more frequently than undergrade (18%) compared with the reference genitourinary pathologist. Interobserver variability tended to worsen with a decrease in tissue quality. CONCLUSION: Tissue-based studies on prostate cancer in men of African descent are essential for a better understanding of this common disease. Standardized tissue handling protocols are crucial to ensure good tissue quality and data. The use of digital slide imaging can enhance collaboration among pathologists in multinational, multicenter studies.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/patología , África del Sur del Sahara , Proyectos Piloto , Clasificación del Tumor
11.
Nat Commun ; 14(1): 4322, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37468456

RESUMEN

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.


Asunto(s)
Ácidos Grasos Omega-3 , Neoplasias de la Próstata , Ácidos Grasos trans , Masculino , Humanos , Estados Unidos/epidemiología , Ghana/epidemiología , Ácido Graso Desaturasas/genética , Ácidos Grasos , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/genética , Polimorfismo de Nucleótido Simple
12.
Eur Urol ; 84(1): 13-21, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36872133

RESUMEN

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.


Asunto(s)
Predisposición Genética a la Enfermedad , Neoplasias de la Próstata , Masculino , Humanos , Estudio de Asociación del Genoma Completo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/epidemiología , Factores de Riesgo , Población Negra/genética
13.
Nat Commun ; 14(1): 8081, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057307

RESUMEN

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.


Asunto(s)
Linfoma de Burkitt , Masculino , Niño , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/patología , Ghana , Aberraciones Cromosómicas , Leucocitos/patología , Inmunoglobulinas/genética , Translocación Genética
14.
Nat Commun ; 13(1): 1759, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35365620

RESUMEN

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.


Asunto(s)
Neoplasias de la Próstata , Proteómica , Negro o Afroamericano , Población Negra/genética , Ghana , Humanos , Masculino , Neoplasias de la Próstata/patología
15.
Am J Hematol ; 86(7): 554-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21674575

RESUMEN

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.


Asunto(s)
Hipergammaglobulinemia/sangre , Hipergammaglobulinemia/epidemiología , Inmunoglobulina G/sangre , Adulto , Anciano , Ghana/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante
16.
Virol J ; 7: 336, 2010 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-21092196

RESUMEN

BACKGROUND: Several studies have suggested that elevated serum alanine aminotransferase (ALT) and asparte aminotransferase (AST) may be markers of hepatitis E virus (HEV) infection. Thus, individuals with elevated ALT and AST may have ongoing subclinical infection of HEV. We estimated the prevalence of anti-HEV antibodies and serum ALT and AST levels among persons who work with pigs in Accra, Ghana. RESULTS: Three hundred and fifty- persons who work with pigs provided blood samples for unlinked anonymous testing for the presence of antibodies to HEV, ALT and AST levels. The median age of participants was 32.85±11.38 years (range 15-70 years). HEV seroprevelance was 34.84%. Anti-HEV IgG was detected in 19.26% while anti-HEV IgM was detected in 15.58% of the persons who tested positive. On multivariate analysis, the independent determinants of HEV infection were, being employed on the farm for less than six months [odds ratio (OR) 8.96; 95% confidence interval (95% CI) 5.43-14.80], having piped water in the household and/or on the farm (OR 13.33; 95% CI 5.23-33.93) and consumption of alcohol (OR 4.91: 95% CI 2.65-9.10). Levels>3× the expected maximum were found for both ALT and AST among individuals who tested positive for anti-HEV IgG (ALT, 210.17±11.64 U/L; AST, 127.18±11.12 U/L) and anti-HEV IgM (ALT, 200.97±10.76 U/L; AST, 120.00±15.96 U/L). CONCLUSION: Consistent with similar studies worldwide, the results of our studies revealed a high prevalence of HEV infection, ALT and AST values in pig handlers.


Asunto(s)
Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Anticuerpos Antihepatitis/sangre , Hepatitis E/epidemiología , Exposición Profesional , Adolescente , Adulto , Distribución por Edad , Anciano , Agricultura , Animales , Ghana/epidemiología , Hepatitis E/patología , Virus de la Hepatitis E/inmunología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Estudios Seroepidemiológicos , Porcinos , Adulto Joven
17.
JCO Glob Oncol ; 6: 610-616, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32302237

RESUMEN

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.


Asunto(s)
Atención a la Salud , Neoplasias , Sistema de Registros , Países en Desarrollo , Ghana/epidemiología , Humanos , Incidencia , Neoplasias/epidemiología
18.
Virol J ; 6: 108, 2009 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-19619291

RESUMEN

BACKGROUND: Hepatitis E virus (HEV) is highly endemic in several African countries with high mortality rate among pregnant women. The prevalence of antibodies to HEV in Ghana is not known. Therefore we evaluated the prevalence of anti-HEV IgG and anti-HEV IgM among pregnant women seen between the months of January and May, 2008 at the Obstetrics and Gynaecology Department, Korle-Bu Teaching Hospital, Accra, Ghana. RESULTS: One hundred and fifty-seven women provided blood samples for unlinked anonymous testing for the presence of antibodies to HEV. The median age of participants was 28.89 +/- 5.76 years (range 13-42 years). Of the 157 women tested, HEV seroprevelance was 28.66% (45/157). Among the seropositive women, 64.40% (29/45) tested positive for anti-HEV IgM while 35.60% (16/45) tested positive to HEV IgG antibodies. HEV seroprevalence was highest (46.15%) among women 21-25 years of age, followed by 42.82% in = 20 year group, then 36.84% in = 36 year group. Of the 157 women, 75.79% and 22.92% were in their third and second trimesters of pregnancy, respectively. Anti-HEV antibodies detected in women in their third trimester of pregnancy (30.25%) was significantly higher, P < 0.05, than in women in their second trimester of pregnancy (25.0%). CONCLUSION: Consistent with similar studies worldwide, the results of our studies revealed a high prevalence of HEV infection in pregnant women.


Asunto(s)
Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E/epidemiología , Complicaciones Infecciosas del Embarazo/epidemiología , Adolescente , Adulto , Factores de Edad , Femenino , Ghana/epidemiología , Anticuerpos Antihepatitis/sangre , Virus de la Hepatitis E/inmunología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Embarazo , Estudios Seroepidemiológicos , Adulto Joven
19.
Jpn J Infect Dis ; 62(4): 265-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19628902

RESUMEN

Reports from studies conducted in several countries indicate a high incidence of bacterial contamination of donor blood. The prevalence of bacterial contamination of blood and its products in Ghana is not known. This study was conducted to determine the prevalence of bacterial contamination of blood and its products at the three major blood transfusion centers in the Greater Accra Region of Ghana. Stored whole blood and its products were cultured on different media, and isolates were identified using standard biochemical and bacteriological methods. The susceptibility of the isolates to selected antimicrobial agents was also determined by the disc diffusion method. The overall prevalence rate was 9% (28/303; whole blood, 13% [24/192]; plasma, 3% [2/79]; platelet, 9% [2/22]). The Gram-positive bacteria isolated were coagulase-negative Staphylococcus, S. aureus, and Bacillus spp., and the Gram-negative organisms were Yersinia enterocolitica, Citrobacter freundii, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The Gram-positive bacteria were sensitive to cloxacillin, erythromycin, tetracycline, and gentamicin but resistant to penicillin, ampicillin, cefuroxime, and cotrimoxazole, while the Gram-negative bacteria were sensitive to amikacin and gentamicin but resistant to chloramphenicol, tetracycline, ampicillin, cefuroxime, cefotaxime (except Y. enterocolitica), and cotrimoxazole. Our results suggest that bacterial contamination of blood and its products is prevalent in Ghana.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Conservación de la Sangre , Sangre/microbiología , Contaminación de Medicamentos , Ghana , Humanos , Pruebas de Sensibilidad Microbiana , Prevalencia
20.
Mol Biochem Parasitol ; 162(2): 172-6, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18848585

RESUMEN

The severity of malaria is multi-factorial. It is associated with parasite-induced alteration in pro-inflammatory and anti-inflammatory cytokine and chemokine levels in host serum and cerebrospinal fluid. It is also associated with sequestration and cytoadherence of parasitized erythrocytes (pRBCs) in post-capillary venules and blood-brain barrier (BBB) dysfunction. The role of these factors in development of vascular injury and tissue damage in malaria patients is unclear. While some studies indicate a requirement for pRBC adhesion to vascular endothelial cells (ECs) in brain capillaries to induce apoptosis and BBB damage, others show no role of apoptosis resulting from adhesion of pRBC to EC. In the present study, the hypothesis that soluble factors from Plasmodium falciparum-infected erythrocytes induce apoptosis in human brain vascular endothelial (HBVEC) and neuroglia cells (cellular components of the BBB) was tested. Apoptotic effects of parasitized (pRBC) and non-parasitized erythrocyte (RBC) conditioned medium on HBVEC and neuroglia cells were determined in vitro by evaluating nuclear DNA fragmentation (TUNEL assay) in cultured cells. Soluble factors from P. falciparum-infected erythrocytes in conditioned medium induced extensive DNA fragmentation in both cell lines, albeit to a greater extent in HBVEC than neuroglia, indicating that extended exposure to high levels of these soluble factors in serum may be associated with vascular, neuronal and tissue injury in malaria patients.


Asunto(s)
Apoptosis , Encéfalo/citología , Endotelio Vascular/citología , Eritrocitos/parasitología , Neuroglía/citología , Plasmodium falciparum/metabolismo , Plasmodium falciparum/patogenicidad , Animales , Barrera Hematoencefálica/metabolismo , Encéfalo/irrigación sanguínea , Encéfalo/metabolismo , Células Cultivadas , Células Endoteliales/metabolismo , Células Endoteliales/parasitología , Humanos , Neuroglía/metabolismo , Neuroglía/parasitología
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