126 results on '"Ayers LW"'
Search Results
2. Value of CD44 immunostaining (IHC) as a surrogate in the differentiation of MYC-positive Burkitt lymphoma (BL) and Burkitt lymphoma-like (BLL) from MYC-negative Diffuse Large B-Cell Lymphoma (DLBCL) in a resource constrained clinical setting
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Bhatia K, Mbulaiteye SM, Zhou W, Ogwang M, and Ayers LW
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 ,Infectious and parasitic diseases ,RC109-216 - Published
- 2009
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3. The effects of frozen tissue storage conditions on the integrity of RNA and protein
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Auer, H, primary, Mobley, JA, additional, Ayers, LW, additional, Bowen, J, additional, Chuaqui, RF, additional, Johnson, LA, additional, Livolsi, VA, additional, Lubensky, IA, additional, McGarvey, D, additional, Monovich, LC, additional, Moskaluk, CA, additional, Rumpel, CA, additional, Sexton, KC, additional, Washington, MK, additional, Wiles, KR, additional, Grizzle, WE, additional, and Ramirez, NC, additional
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- 2014
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4. Development and application of a real time PCR assay for detection and quantification of merkel cell virus (MCV) in archived formalin fixed paraffin embedded tissue samples of merkel cell carcinoma and other cancers
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Modali, R, primary, Goedert, J, additional, Engels, E, additional, Ayers, LW, additional, and Bhatia, K, additional
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- 2009
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5. Evaluation of Epstein-Barr virus (EBV) and human herpes virus-8 (HHV-8) in HIV-associated persistent generalized lymphadenopathy (PGL)
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Ayers, LW, primary, Dominguez, G, additional, and Bhatia, K, additional
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- 2009
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6. Value of CD44 immunostaining (IHC) as a surrogate in the differentiation of MYC-positive Burkitt lymphoma (BL) and Burkitt lymphoma-like (BLL) from MYC-negative Diffuse Large B-Cell Lymphoma (DLBCL) in a resource constrained clinical setting
- Author
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Ayers, LW, primary, Ogwang, M, additional, Zhou, W, additional, Mbulaiteye, SM, additional, and Bhatia, K, additional
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- 2009
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7. Dose-modified oral chemotherapy in the treatment of AIDS-related non-Hodgkin's lymphoma in East Africa.
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Mwanda WO, Orem J, Fu P, Banura C, Kakembo J, Onyango CA, Ness A, Reynolds S, Johnson JL, Subbiah V, Bako J, Wabinga H, Abdallah FK, Meyerson HJ, Whalen CC, Lederman MM, Black J, Ayers LW, Katongole-Mbidde E, and Remick SC
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- 2009
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8. A plea for more rationaluse of 'cold sterilization' procedures in Podiatric medicine
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Stewart Rc and Ayers Lw
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medicine.medical_specialty ,business.industry ,General surgery ,Podiatry ,Sterilization ,General Medicine ,Surgery ,Disinfection ,Plea ,Sterilization (medicine) ,medicine ,Humans ,Benzalkonium Compounds ,Drug Contamination ,business ,Disinfectants - Published
- 1977
9. Acute leprosy in Ohio during treatment of HIV-AIDS.
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Sopirala MM, Wininger DA, and Ayers LW
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- 2011
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10. Protein arginine methyltransferase 5 (PRMT5) inhibition induces lymphoma cell death through reactivation of the retinoblastoma tumor suppressor pathway and polycomb repressor complex 2 (PRC2) silencing
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Claudio Agostinelli, Saïd Sif, Robert A. Baiocchi, Leona W. Ayers, Vrajesh Karkhanis, Sookil Tae, Stefano Pileri, Gerald V. Denis, Fengting Yan, Jihyun Chung, Porsha Smith, Chung J, Karkhanis V, Tae S, Yan F, Smith P, Ayers LW, Agostinelli C, Pileri S, Denis GV, Baiocchi RA, and Sif S
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Protein-Arginine N-Methyltransferases ,Lymphoma ,Cyclin A ,Repressor ,Histone Deacetylase 2 ,macromolecular substances ,medicine.disease_cause ,Biochemistry ,Retinoblastoma Protein ,Epigenesis, Genetic ,Mice ,Cyclin D1 ,immune system diseases ,hemic and lymphatic diseases ,Cell Line, Tumor ,medicine ,Tumor Cells, Cultured ,Animals ,Humans ,Protein Methyltransferases ,Genes, Retinoblastoma ,Promoter Regions, Genetic ,Molecular Biology ,neoplasms ,Derepression ,biology ,Cell Death ,Retinoblastoma-Like Protein p130 ,Protein arginine methyltransferase 5 ,Lymphoma, Non-Hodgkin ,Retinoblastoma protein ,Polycomb Repressive Complex 2 ,Molecular Bases of Disease ,Cell Biology ,BCL10 ,Gene Knockdown Techniques ,biology.protein ,Cancer research ,Carcinogenesis ,Signal Transduction - Abstract
Epigenetic regulation mediated by lysine- and arginine-specific enzymes plays an essential role in tumorigenesis, and enhanced expression of the type II protein arginine methyltransferase PRMT5 as well as the polycomb repressor complex PRC2 has been associated with increased cell proliferation and survival. Here, we show that PRMT5 is overexpressed in three different types of non-Hodgkin lymphoma cell lines and clinical samples as well as in mouse primary lymphoma cells and that it up-regulates PRC2 expression through inactivation of the retinoblastoma proteins RB1 and RBL2. Although PRMT5 epigenetically controls RBL2 expression, it indirectly promotes RB1 phosphorylation through enhanced cyclin D1 expression. Furthermore, we demonstrate that PRMT5 knockdown in non-Hodgkin lymphoma cell lines and mouse primary lymphoma cells leads to RBL2 derepression and RB1 reactivation, which in turn inhibit PRC2 expression and trigger derepression of its CASP10, DAP1, HOXA5, and HRK pro-apoptotic target genes. We also show that reduced PRMT5 expression leads to cyclin D1 transcriptional repression via loss of TP53K372 methylation, which results in decreased BCL3 expression and enhanced recruitment of NF-κB p52-HDAC1 repressor complexes to the cyclin D1 promoter. These findings indicate that PRMT5 is a master epigenetic regulator that governs expression of its own target genes and those regulated by PRC2 and that its inhibition could offer a promising therapeutic strategy for lymphoma patients.
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- 2013
11. Plasma metabolites in childhood Burkitt lymphoma cases and cancer-free controls in Uganda.
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Huang J, Nabalende H, Camargo MC, Lovett J, Otim I, Legason ID, Ogwang MD, Kerchan P, Kinyera T, Ayers LW, Bhatia K, Goedert JJ, Reynolds SJ, Crompton PD, Moore SC, Moaddel R, Albanes D, and Mbulaiteye SM
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- Humans, Child, Uganda epidemiology, Male, Case-Control Studies, Metabolome, Female, Burkitt Lymphoma blood, Burkitt Lymphoma metabolism, Metabolomics methods
- Abstract
Introduction: Burkitt lymphoma (BL) is an aggressive non-Hodgkin lymphoma associated with Plasmodium falciparum and Epstein-Barr virus, both of which affect metabolic pathways. The metabolomic patterns of BL is unknown., Materials and Methods: We measured 627 metabolites in pre-chemotherapy treatment plasma samples from 25 male children (6-11 years) with BL and 25 cancer-free area- and age-frequency-matched male controls from the Epidemiology of Burkitt Lymphoma in East African Children and Minors study in Uganda using liquid chromatography-tandem mass spectrometry. Unconditional, age-adjusted logistic regression analysis was used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs) for the BL association with 1-standard deviation increase in the log-metabolite concentration, adjusting for multiple comparisons using false discovery rate (FDR) thresholds and Bonferroni correction., Results: Compared to controls, levels for 42 metabolite concentrations differed in BL cases (FDR < 0.001), including triacylglyceride (18:0_38:6), alpha-aminobutyric acid (AABA), ceramide (d18:1/20:0), phosphatidylcholine ae C40:6 and phosphatidylcholine C38:6 as the top signals associated with BL (ORs = 6.9 to 14.7, P < 2.4✕10
- 4 ). Two metabolites (triacylglyceride (18:0_38:6) and AABA) selected using stepwise logistic regression discriminated BL cases from controls with an area under the curve of 0.97 (95% CI: 0.94, 1.00)., Conclusion: Our findings warrant further examination of plasma metabolites as potential biomarkers for BL risk/diagnosis., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)- Published
- 2024
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12. Human leukocyte antigen-DQA1*04:01 and rs2040406 variants are associated with elevated risk of childhood Burkitt lymphoma.
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Liu Z, Luo Y, Kirimunda S, Verboom M, Onabajo OO, Gouveia MH, Ogwang MD, Kerchan P, Reynolds SJ, Tenge CN, Were PA, Kuremu RT, Wekesa WN, Masalu N, Kawira E, Kinyera T, Otim I, Legason ID, Nabalende H, Dhudha H, Ayers LW, Bhatia K, Goedert JJ, Cole N, Luo W, Liu J, Manning M, Hicks B, Prokunina-Olsson L, Chagaluka G, Johnston WT, Mutalima N, Borgstein E, Liomba GN, Kamiza S, Mkandawire N, Mitambo C, Molyneux EM, Newton R, Hsing AW, Mensah JE, Adjei AA, Hutchinson A, Carrington M, Yeager M, Blasczyk R, Chanock SJ, Raychaudhuri S, and Mbulaiteye SM
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- Child, Humans, Herpesvirus 4, Human genetics, HLA-DQ alpha-Chains genetics, Burkitt Lymphoma genetics, Epstein-Barr Virus Infections complications, Epstein-Barr Virus Infections genetics
- Abstract
Burkitt lymphoma (BL) is responsible for many childhood cancers in sub-Saharan Africa, where it is linked to recurrent or chronic infection by Epstein-Barr virus or Plasmodium falciparum. However, whether human leukocyte antigen (HLA) polymorphisms, which regulate immune response, are associated with BL has not been well investigated, which limits our understanding of BL etiology. Here we investigate this association among 4,645 children aged 0-15 years, 800 with BL, enrolled in Uganda, Tanzania, Kenya, and Malawi. HLA alleles are imputed with accuracy >90% for HLA class I and 85-89% for class II alleles. BL risk is elevated with HLA-DQA1*04:01 (adjusted odds ratio [OR] = 1.61, 95% confidence interval [CI] = 1.32-1.97, P = 3.71 × 10
-6 ), with rs2040406(G) in HLA-DQA1 region (OR = 1.43, 95% CI = 1.26-1.63, P = 4.62 × 10-8 ), and with amino acid Gln at position 53 versus other variants in HLA-DQA1 (OR = 1.36, P = 2.06 × 10-6 ). The associations with HLA-DQA1*04:01 (OR = 1.29, P = 0.03) and rs2040406(G) (OR = 1.68, P = 0.019) persist in mutually adjusted models. The higher risk rs2040406(G) variant for BL is associated with decreased HLA-DQB1 expression in eQTLs in EBV transformed lymphocytes. Our results support the role of HLA variation in the etiology of BL and suggest that a promising area of research might be understanding the link between HLA variation and EBV control., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)- Published
- 2024
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13. Sickle cell allele HBB-rs334(T) is associated with decreased risk of childhood Burkitt lymphoma in East Africa.
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Hong HG, Gouveia MH, Ogwang MD, Kerchan P, Reynolds SJ, Tenge CN, Were PA, Kuremu RT, Wekesa WN, Masalu N, Kawira E, Kinyera T, Wang X, Zhou J, Leal TP, Otim I, Legason ID, Nabalende H, Dhudha H, Mumia M, Baker FS, Okusolubo T, Ayers LW, Bhatia K, Goedert JJ, Woo J, Manning M, Cole N, Luo W, Hicks B, Chagaluka G, Johnston WT, Mutalima N, Borgstein E, Liomba GN, Kamiza S, Mkandawire N, Mitambo C, Molyneux EM, Newton R, Hutchinson A, Yeager M, Adeyemo AA, Thein SL, Rotimi CN, Chanock SJ, Prokunina-Olsson L, and Mbulaiteye SM
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- Humans, Africa, Eastern, Alleles, Nectins metabolism, Burkitt Lymphoma epidemiology, Burkitt Lymphoma genetics, Malaria, Malaria, Falciparum epidemiology, Malaria, Falciparum genetics, Malaria, Falciparum complications, Sickle Cell Trait epidemiology, Sickle Cell Trait genetics, Sickle Cell Trait complications
- Abstract
Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that significantly contributes to childhood cancer burden in sub-Saharan Africa. Plasmodium falciparum, which causes malaria, is geographically associated with BL, but the evidence remains insufficient for causal inference. Inference could be strengthened by demonstrating that mendelian genes known to protect against malaria-such as the sickle cell trait variant, HBB-rs334(T)-also protect against BL. We investigated this hypothesis among 800 BL cases and 3845 controls in four East African countries using genome-scan data to detect polymorphisms in 22 genes known to affect malaria risk. We fit generalized linear mixed models to estimate odds ratios (OR) and 95% confidence intervals (95% CI), controlling for age, sex, country, and ancestry. The ORs of the loci with BL and P. falciparum infection among controls were correlated (Spearman's ρ = 0.37, p = .039). HBB-rs334(T) was associated with lower P. falciparum infection risk among controls (OR = 0.752, 95% CI 0.628-0.9; p = .00189) and BL risk (OR = 0.687, 95% CI 0.533-0.885; p = .0037). ABO-rs8176703(T) was associated with decreased risk of BL (OR = 0.591, 95% CI 0.379-0.992; p = .00271), but not of P. falciparum infection. Our results increase support for the etiological correlation between P. falciparum and BL risk., (© 2023 Wiley Periodicals LLC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)
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- 2024
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14. Mosaic chromosomal alterations in peripheral blood leukocytes of children in sub-Saharan Africa.
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Zhou W, Fischer A, Ogwang MD, Luo W, Kerchan P, Reynolds SJ, Tenge CN, Were PA, Kuremu RT, Wekesa WN, Masalu N, Kawira E, Kinyera T, Otim I, Legason ID, Nabalende H, Ayers LW, Bhatia K, Goedert JJ, Gouveia MH, Cole N, Hicks B, Jones K, Hummel M, Schlesner M, Chagaluka G, Mutalima N, Borgstein E, Liomba GN, Kamiza S, Mkandawire N, Mitambo C, Molyneux EM, Newton R, Glaser S, Kretzmer H, Manning M, Hutchinson A, Hsing AW, Tettey Y, Adjei AA, Chanock SJ, Siebert R, Yeager M, Prokunina-Olsson L, Machiela MJ, and Mbulaiteye SM
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- Male, Child, Humans, Ghana, Chromosome Aberrations, Leukocytes pathology, Immunoglobulins genetics, Translocation, Genetic, Burkitt Lymphoma genetics, Burkitt Lymphoma pathology
- Abstract
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., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)- Published
- 2023
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15. The emergence of SARS-CoV-2 lineages and associated saliva antibody responses among asymptomatic individuals in a large university community.
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Merling MR, Williams A, Mahfooz NS, Ruane-Foster M, Smith J, Jahnes J, Ayers LW, Bazan JA, Norris A, Norris Turner A, Oglesbee M, Faith SA, Quam MB, and Robinson RT
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- Aged, Humans, SARS-CoV-2, Saliva, Universities, Breakthrough Infections, Immunoglobulin A, Immunoglobulin G, Immunoglobulin M, Antibody Formation, COVID-19 epidemiology
- Abstract
SARS-CoV-2 (CoV2) infected, asymptomatic individuals are an important contributor to COVID transmission. CoV2-specific immunoglobulin (Ig)-as generated by the immune system following infection or vaccination-has helped limit CoV2 transmission from asymptomatic individuals to susceptible populations (e.g. elderly). Here, we describe the relationships between COVID incidence and CoV2 lineage, viral load, saliva Ig levels (CoV2-specific IgM, IgA and IgG), and ACE2 binding inhibition capacity in asymptomatic individuals between January 2021 and May 2022. These data were generated as part of a large university COVID monitoring program in Ohio, United States of America, and demonstrate that COVID incidence among asymptomatic individuals occurred in waves which mirrored those in surrounding regions, with saliva CoV2 viral loads becoming progressively higher in our community until vaccine mandates were established. Among the unvaccinated, infection with each CoV2 lineage (pre-Omicron) resulted in saliva Spike-specific IgM, IgA, and IgG responses, the latter increasing significantly post-infection and being more pronounced than N-specific IgG responses. Vaccination resulted in significantly higher Spike-specific IgG levels compared to unvaccinated infected individuals, and uninfected vaccinees' saliva was more capable of inhibiting Spike function. Vaccinees with breakthrough Delta infections had Spike-specific IgG levels comparable to those of uninfected vaccinees; however, their ability to inhibit Spike binding was diminished. These data are consistent with COVID vaccines having achieved hoped-for effects in our community, including the generation of mucosal antibodies that inhibit Spike and lower community viral loads, and suggest breakthrough Delta infections were not due to an absence of vaccine-elicited Ig, but instead limited Spike binding activity in the face of high community viral loads., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Merling et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2023
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16. Burkitt lymphoma risk shows geographic and temporal associations with Plasmodium falciparum infections in Uganda, Tanzania, and Kenya.
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Broen K, Dickens J, Trangucci R, Ogwang MD, Tenge CN, Masalu N, Reynolds SJ, Kawira E, Kerchan P, Were PA, Kuremu RT, Wekesa WN, Kinyera T, Otim I, Legason ID, Nabalende H, Buller ID, Ayers LW, Bhatia K, Biggar RJ, Goedert JJ, Wilson ML, Mbulaiteye SM, and Zelner J
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- Humans, Plasmodium falciparum, Case-Control Studies, Uganda epidemiology, Kenya epidemiology, Tanzania epidemiology, Cross-Sectional Studies, Burkitt Lymphoma epidemiology, Burkitt Lymphoma genetics, Malaria, Falciparum complications, Malaria, Falciparum epidemiology, Malaria, Falciparum parasitology, Malaria epidemiology
- Abstract
Endemic Burkitt lymphoma (eBL) is a pediatric cancer coendemic with malaria in sub-Saharan Africa, suggesting an etiological link between them. However, previous cross-sectional studies of limited geographic areas have not found a convincing association. We used spatially detailed data from the Epidemiology of Burkitt Lymphoma in East African Children and Minors (EMBLEM) study to assess this relationship. EMBLEM is a case-control study of eBL from 2010 through 2016 in six regions of Kenya, Uganda, and Tanzania. To measure the intensity of exposure to the malaria parasite, Plasmodium falciparum , among children in these regions, we used high-resolution spatial data from the Malaria Atlas Project to estimate the annual number of P. falciparum infections from 2000 through 2016 for each of 49 districts within the study region. Cumulative P. falciparum exposure, calculated as the sum of annual infections by birth cohort, varied widely, with a median of 47 estimated infections per child by age 10, ranging from 4 to 315 infections. eBL incidence increased 39% for each 100 additional lifetime P. falciparum infections (95% CI: 6.10 to 81.04%) with the risk peaking among children aged 5 to 11 and declining thereafter. Alternative models using estimated annual P. falciparum infections 0 to 10 y before eBL onset were inconclusive, suggesting that eBL risk is a function of cumulative rather than recent cross-sectional exposure. Our findings provide population-level evidence that eBL is a phenotype related to heavy lifetime exposure to P. falciparum malaria and support emphasizing the link between malaria and eBL.
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- 2023
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17. Accuracy of whole slide image based image analysis is adversely affected by preanalytical factors such as stained tissue slide and paraffin block age.
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Shaker N, Sardana R, Hamasaki S, Nohle DG, Ayers LW, and Parwani AV
- Abstract
Background: Personalized medicine and accurate quantification of tumor and biomarker expression have become the cornerstone of cancer diagnostics. This requires Quality Control (QC) of research tissue samples to confirm adequate targeted tumor tissue sampling. Digitalization of stained tissue slides offer a precious way to archive, preserve, and retrieve necessary information when needed. This study is aimed to assess the most significant pre-analytic and analytic factors that might contribute to the efficacy of obtaining accurate whole slide images (WSIs) interpretation. Various studies are needed to identifysuch factors to allow for appropriate AI application and adequate tumor area/percentage quantification., Methods: Hematoxylene and Eosine (H&E) satined WSIs collected from tissue specimens provided by the Cooperative Human Tissue Network (CHTN) Midwestern Division (CHTNMWD) were analyzed. Tissue specimens were processed, fixed, stained, and scanned contemporaneously (within 1 month). Two cohorts of malignant, colorectal cancer, 20X WSI (ScanscopeXT, Leica Biosystems, Illinois), were assembled. The study identified a "recent cohort" that included 76 WSIs created on 2018 or later. "Aged cohort" included 73 WSIs from specimens procured in the period of (2012-2014). Twenty recent WSIs of adenocarcinoma cases were used to construct WSIs analysis algorithms (VIS, Visiopharm A/S, Denmark) using machine learning to produce morphometric maps and calculate tissue and tumor areas., Results: Algorithmic analysis of 69 WSIs from rescanned aged slides vs. that of contemporaneous WSIs concluded 18 (28%) similar finding in tumor areas (within 10%), 56 (82%) had identicaltissue areas, and 54 (79%) had similar tumor percentages., Conclusion: WSIs of aged H&E slides and stained paraffin block re-cuts produce different tumor quantification compared to those of original scanned sslides most likely due to pre-analytical factors. The difference in tumor area detected between original and rescanned WSIs trended upward in the period between 2012 and 2014. Less tumor area was detected as the slides age. Recut and H&E-stained tissues from stored paraffin blocks may detect more tumor due to excess eosinophilia. These results highlights the value of documenting archives of H&E WSIs collected at the procurement time. Such images provide a superior archive over glass slides and Formalin-Fixed Paraffin-Embedded (FFPE) blocks and contribute betterg to WSIs analysis application., (© 2022 The Authors.)
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- 2022
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18. Epstein-Barr Virus in Burkitt Lymphoma in Africa Reveals a Limited Set of Whole Genome and LMP-1 Sequence Patterns: Analysis of Archival Datasets and Field Samples From Uganda, Tanzania, and Kenya.
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Liao HM, Liu H, Chin PJ, Li B, Hung GC, Tsai S, Otim I, Legason ID, Ogwang MD, Reynolds SJ, Kerchan P, Tenge CN, Were PA, Kuremu RT, Wekesa WN, Masalu N, Kawira E, Ayers LW, Pfeiffer RM, Bhatia K, Goedert JJ, Lo SC, and Mbulaiteye SM
- Abstract
Epstein-Barr virus (EBV) is associated with endemic Burkitt lymphoma (eBL), but the contribution of EBV variants is ill-defined. Studies of EBV whole genome sequences (WGS) have identified phylogroups that appear to be distinct for Asian versus non-Asian EBV, but samples from BL or Africa, where EBV was first discovered, are under-represented. We conducted a phylogenetic analysis of EBV WGS and LMP-1 sequences obtained primarily from BL patients in Africa and representative non-African EBV from other conditions or regions using data from GenBank, Sequence Read Archive, or Genomic Data Commons for the Burkitt Lymphoma Genome Sequencing Project (BLGSP) to generate data to support the use of a simpler biomarker of geographic or phenotypic associations. We also investigated LMP-1 patterns in 414 eBL cases and 414 geographically matched controls in the Epidemiology of Burkitt Lymphoma in East African children and minors (EMBLEM) study using LMP-1 PCR and Sanger sequencing. Phylogenetic analysis revealed distinct genetic patterns of African versus Asian EBV sequences. We identified 281 single nucleotide variations (SNVs) in LMP-1 promoter and coding region, which formed 12 unique patterns (A to L). Nine patterns (A, AB, C, D, F, I, J, K and L) predominated in African EBV, of which four were found in 92% of BL samples (A, AB, D, and H). Predominant patterns were B and G in Asia and H in Europe. EBV positivity in peripheral blood was detected in 95.6% of EMBLEM eBL cases versus 79.2% of the healthy controls (odds ratio [OR] =3.83; 95% confidence interval 2.06-7.14). LMP-1 was successfully sequenced in 66.7% of the EBV DNA positive cases but in 29.6% of the controls (ORs ranging 5-11 for different patterns). Four LMP-1 patterns (A, AB, D, and K) were detected in 63.1% of the cases versus 27.1% controls (ORs ranges: 5.58-11.4). Dual strain EBV infections were identified in WGS and PCR-Sanger data. In conclusion, EBV from Africa is phylogenetically separate from EBV in Asia. Genetic diversity in LMP-1 formed 12 patterns, which showed promising geographic and phenotypic associations. Presence of multiple strain infection should be considered in efforts to refine or improve EBV markers of ancestry or phenotype., Lay Summary: Epstein-Barr virus (EBV) infection, a ubiquitous infection, contributes to the etiology of both Burkitt Lymphoma (BL) and nasopharyngeal carcinoma, yet their global distributions vary geographically with no overlap. Genomic variation in EBV is suspected to play a role in the geographical patterns of these EBV-associated cancers, but relatively few EBV samples from BL have been comprehensively studied. We sought to compare phylogenetic patterns of EBV genomes obtained from BL samples in Africa and from tumor and non-tumor samples from elsewhere. We concluded that EBV obtained from BL in Africa is genetically separate from EBV in Asia. Through comprehensive analysis of nucleotide variations in EBV's LMP-1 gene, we describe 12 LMP-1 patterns, two of which (B and G) were found mostly in Asia. Four LMP-1 patterns (A, AB, D, and F) accounted for 92% of EBVs sequenced from BL in Africa. Our results identified extensive diversity of EBV, but BL in Africa was associated with a limited number of variants identified, which were different from those identified in Asia. Further research is needed to optimize the use of PCR and sequencing to study LMP-1 diversity for classification of EBV variants and for use in epidemiologic studies to characterize geographic and/or phenotypic associations of EBV variants with EBV-associated malignancies, including eBL., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Liao, Liu, Chin, Li, Hung, Tsai, Otim, Legason, Ogwang, Reynolds, Kerchan, Tenge, Were, Kuremu, Wekesa, Masalu, Kawira, Ayers, Pfeiffer, Bhatia, Goedert, Lo and Mbulaiteye.)
- Published
- 2022
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19. COVID-19 Pandemic Impact on Cooperative Human Tissue Network Midwestern Division Service to Investigators.
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Mandt RL, Nohle DG, Sardana R, Couce ME, Ayers LW, and Parwani AV
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- Humans, SARS-CoV-2, COVID-19, Pandemics
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- 2021
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20. Inverse association of falciparum positivity with endemic Burkitt lymphoma is robust in analyses adjusting for pre-enrollment malaria in the EMBLEM case-control study.
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Peprah S, Ogwang MD, Kerchan P, Reynolds SJ, Tenge CN, Were PA, Kuremu RT, Wekesa WN, Masalu N, Kawira E, Otim I, Legason ID, Ayers LW, Bhatia K, Goedert JJ, Pfeiffer RM, and Mbulaiteye SM
- Abstract
Background: Falciparum and endemic Burkitt lymphoma (eBL) are co-endemic in Africa, but the malaria experience in eBL patients is unknown. A lower prevalence of falciparum has been reported in eBL patients, but those results are anecdotally attributed to pre-enrollment anti-malaria treatment., Methods: We studied 677 eBL patients and 2920 community controls aged 0-15 years enrolled in six regions in Uganda, Tanzania, and Kenya during 2010-2016. Falciparum was diagnosed using thick blood film microscopy (TFM) and antigen-capture rapid diagnostic tests (RDTs). Guardians of the children answered a 40-item structured questionnaire about their child's pre-enrollment lifetime malaria history and treatment, demographics, socioeconomics, animal exposures, fevers, and hospitalizations. We utilized exploratory factor analysis to reduce the 40 questionnaire variables into six factors, including Inpatient malaria and Outpatient malaria factors that were surrogates of pre-enrollment anti-malaria treatment. The six factors accounted for 83-90% of the variance in the questionnaire data. We calculated odds ratios and 95% confidence intervals (OR 95% CI) of association of eBL with falciparum positivity, defined as positive both on TFM or RDTs, or only RDTs (indicative of recent infection) or TFM (indicative of current falciparum infection) versus no infection, using multivariable logistic regression, controlling for group of age (0-2, 3-5, 6-8, 9-11 and 12-15 years), sex, and study site and the afore-mentioned pre-enrollment factors., Results: The prevalence of falciparum infection was 25.6% in the eBL cases and 45.7% in community controls (aOR = 0.43, 95% CI: 0.40, 0.47; P < 0.0001). The results were similar for recent falciparum infection (6.9% versus 13.5%, aOR = 0.44, 95% CI: 0.38, 0.50; P < 0.0001) and current falciparum infection (18.7% versus 32.1%, aOR = 0.47, 95% CI: 0.43, 0.51; P < 0.0001). These aORs for any, recent and current falciparum infection did not change when we adjusted for pre-enrollment factors (aORs = 0.46, =0.44, and = 0.51, respectively) were significantly lower in stratified analysis for any infection in children < 5 years (aOR = 0.46; 95% CI: 0.29, 0.75) or ≥ 10 years (aOR = 0.47; 95% CI: 0.32, 0.71)., Conclusion: Our study results reduce support for pre-enrollment antimalaria treatment as a sole explanation for the observed lower falciparum prevalence in eBL cases and open a space to consider alternative immunology-based hypotheses.
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- 2021
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21. Author Correction to: Endemic Burkitt lymphoma in second-degree relatives in Northern Uganda: in-depth genome-wide analysis suggests clues about genetic susceptibility.
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Gouveia MH, Otim I, Ogwang MD, Wang M, Zhu B, Cole N, Luo W, Hicks B, Jones K, Oehl-Huber K, Ayers LW, Pittaluga S, Legason ID, Nabalende H, Kerchan P, Kinyera T, Kawira E, Brubaker G, Levin AG, Guertler L, Kim J, Stewart DR, Adde M, Magrath I, Bergen AW, Reynolds SJ, Yeager M, Bhatia K, Adeyemo AA, Prokunina-Olsson L, Dean M, Shriner D, Rotimi CN, Chanock S, Siebert R, and Mbulaiteye SM
- Published
- 2021
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22. Endemic Burkitt Lymphoma in second-degree relatives in Northern Uganda: in-depth genome-wide analysis suggests clues about genetic susceptibility.
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Gouveia MH, Otim I, Ogwang MD, Wang M, Zhu B, Cole N, Luo W, Hicks B, Jones K, Oehl-Huber K, Ayers LW, Pittaluga S, Legason ID, Nabalende H, Kerchan P, Kinyera T, Kawira E, Brubaker G, Levin AG, Guertler L, Kim J, Stewart DR, Adde M, Magrath I, Bergen AW, Reynolds SJ, Yeager M, Bhatia K, Adeyemo AA, Prokunina-Olsson L, Dean M, Shriner D, Rotimi CN, Chanock S, Siebert R, and Mbulaiteye SM
- Subjects
- Endemic Diseases, Genetic Predisposition to Disease, Genome-Wide Association Study, Geography, Humans, Uganda epidemiology, Exome Sequencing, Burkitt Lymphoma epidemiology, Burkitt Lymphoma etiology, Family
- Published
- 2021
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23. Mean platelet counts are relatively decreased with malaria but relatively increased with endemic Burkitt Lymphoma in Uganda, Tanzania, and Kenya.
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Peprah S, Ogwang MD, Kerchan P, Reynolds SJ, Tenge CN, Were PA, Kuremu RT, Wekesa WN, Masalu N, Kawira E, Kinyera T, Otim I, Legason ID, Nabalende H, Dhudha H, Mumia M, Ayers LW, Biggar RJ, Bhatia K, Goedert JJ, and Mbulaiteye SM
- Subjects
- Adolescent, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Kenya, Male, Platelet Count, Tanzania, Uganda, Burkitt Lymphoma blood, Malaria blood
- Abstract
Platelet counts are decreased in Plasmodium falciparum malaria, which is aetiologically linked with endemic Burkitt lymphoma (eBL). However, the pattern of platelet counts in eBL cases is unknown. We studied platelet counts in 582 eBL cases and 2 248 controls enrolled in a case-control study in Uganda, Tanzania and Kenya (2010-2016). Mean platelet counts in controls or eBL cases with or without malaria-infection in controls versus eBLcases were compared using Student's t-test. Odds ratios (ORs) and two-sided 95% confidence intervals (95% CIs) were estimated using multiple logistic regression, controlling for age, sex, haemoglobin and white blood cell counts. Platelets were decreased with malaria infection in the controls [263 vs. 339 × 10
9 platelets/l, P < 0·0001; adjusted OR (aOR) = 3·42, 95% CI: 2·79-4·18] and eBL cases (314 vs. 367 × 109 platelets/l, P-value = 0·002; aOR = 2·36, 95% CI: 1·49-3·73). Unexpectedly, platelets were elevated in eBL cases versus controls in overall analyses (mean: 353 vs. 307 × 109 platelets/l, P < 0·0001; aOR = 1·41; 95% CI: 1·12-1·77), and when restricted to malaria-positive (mean 314 vs. 263 × 109 platelets/l, P < 0·0001; OR = 2·26; 95% CI: 1·56-3·27) or malaria-negative (mean 367 vs. 339 × 109 platelets/l, P < 0·001; OR = 1·46; 95% CI: 1·17-1·83) subjects. Platelets were decreased with malaria infection in controls and eBL cases but elevated with eBL., (© 2020 British Society for Haematology and John Wiley & Sons Ltd.)- Published
- 2020
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24. Endemic Burkitt lymphoma: a complication of asymptomatic malaria in sub-Saharan Africa based on published literature and primary data from Uganda, Tanzania, and Kenya.
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Redmond LS, Ogwang MD, Kerchan P, Reynolds SJ, Tenge CN, Were PA, Kuremu RT, Masalu N, Kawira E, Otim I, Legason ID, Dhudha H, Ayers LW, Bhatia K, Goedert JJ, and Mbulaiteye SM
- Subjects
- Adolescent, Asymptomatic Infections epidemiology, Burkitt Lymphoma parasitology, Case-Control Studies, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Kenya epidemiology, Malaria, Falciparum complications, Malaria, Falciparum parasitology, Male, Plasmodium falciparum physiology, Prevalence, Tanzania epidemiology, Uganda epidemiology, Burkitt Lymphoma epidemiology, Malaria, Falciparum epidemiology
- Abstract
Background: Endemic Burkitt lymphoma (eBL) is an aggressive B cell non-Hodgkin lymphoma associated with antigenic stimulation from Plasmodium falciparum malaria. Whether eBL risk is related to malaria parasite density is unknown. To address this issue, children with eBL, asymptomatic and clinical malaria, as a surrogate of malaria parasite density, were assessed., Methods: Malaria-related laboratory results (parasite density, haemoglobin, platelet count, and white cell count [WBC]) count) were compiled for 4019 eBL cases and 80,532 subjects evaluated for asymptomatic malaria or clinical malaria (severe malaria anaemia, hyperparasitaemia, cerebral malaria, malaria prostration, moderate malaria, and mild malaria) in 21 representative studies published in Africa (mostly East Africa) and 850 eBL cases and 2878 controls with primary data from the Epidemiology of Burkitt Lymphoma in East African Children and Minors (EMBLEM) case-control study in Uganda, Tanzania, and Kenya. The average values of malaria-related laboratory results were computed by condition and trends across single-year age groups were assessed using regression and spline models., Results: Overall, malaria infection or malaria was diagnosed in 37,089 of children compiled from the literature. Children with eBL and asymptomatic parasitaemia/antigenaemia, but not those with clinical malaria, were closest in their mean age (age 7.1-7.2 vs. 7.4-9.8 years), haemoglobin level (10.0-10.4 vs. 11.7-12.3 g/dL), malaria parasite density (2800 vs. 1827-7780 parasites/µL), platelet count (347,000-353,000 vs. 244,000-306,000 platelets/µL), and WBC count (8180-8890 vs. 7100-7410 cells/µL). Parasite density in these two groups peaked between four to five years, then decreased steadily thereafter; conversely, haemoglobin showed a corresponding increase with age. Children with clinical malaria were markedly different: all had an average age below 5 years, had dramatically elevated parasite density (13,905-869,000 parasites/µL) and dramatically decreased platelet count (< 159,000 platelets/µL) and haemoglobin (< 7 g/dL)., Conclusions: eBL and asymptomatic parasitaemia/antigenaemia, but not clinical malaria, were the most similar conditions with respect to mean age and malaria-related laboratory results. These results suggest that children with asymptomatic parasitaemia/antigenaemia may be the population at risk of eBL.
- Published
- 2020
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25. Variation in the Human Leukocyte Antigen system and risk for endemic Burkitt lymphoma in northern Uganda.
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Kirimunda S, Verboom M, Otim I, Ssennono M, Legason ID, Nabalende H, Ogwang MD, Kerchan P, Kinyera T, Mwebaza I, Joloba M, Ayers LW, Reynolds SJ, Bhatia K, Onabajo OO, Hallensleben M, Biggar RJ, Prokunina-Olsson L, Goedert JJ, Blasczyk R, and Mbulaiteye SM
- Subjects
- Adolescent, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Male, Risk Factors, Uganda, Burkitt Lymphoma blood, HLA Antigens metabolism
- Abstract
Endemic Burkitt lymphoma (eBL) is an aggressive childhood B-cell lymphoma associated with Plasmodium falciparum (Pf) malaria and Epstein-Barr virus (EBV) infections. Variation in the Human Leukocyte Antigen (HLA) system is suspected to play a role, but assessments using less accurate serology-based HLA typing techniques in small studies yielded conflicting results. We studied 200 eBL cases and 400 controls aged 0-15 years enrolled in northern Uganda and typed by accurate high-resolution HLA sequencing methods. HLA results were analyzed at one- or two-field resolution. Odds ratios and 95% confidence intervals (aOR, 95% CI) for eBL risk associated with common HLA alleles versus alleles that were rare (<1%) or differed by <2% between the cases and controls as the reference category, were estimated using multiple logistic regression adjusting for age, sex, microgeography, region, malaria positivity and treatment history, and genetic variants associated with eBL. Compared to the controls, eBL cases had a lower frequency of HLA-A*02 (aOR = 0·59, 95% CI 0·38-0·91), HLA-B*41 (aOR = 0·36, 95% CI 0·13-1·00), and HLA-B*58 alleles (aOR = 0·59, 95% CI 0·36-0·97). eBL cases had a lower frequency of HLA-DPB1 homozygosity (aOR = 0·57, 95% CI 0·40-0·82) but a higher frequency of HLA-DQA1 homozygosity (aOR = 2·19, 95% CI 1·42-3·37). Our results suggest that variation in HLA may be associated with eBL risk., (© 2020 British Society for Haematology and John Wiley & Sons Ltd.)
- Published
- 2020
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26. Risk factors for Burkitt lymphoma in East African children and minors: A case-control study in malaria-endemic regions in Uganda, Tanzania and Kenya.
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Peprah S, Ogwang MD, Kerchan P, Reynolds SJ, Tenge CN, Were PA, Kuremu RT, Wekesa WN, Sumba PO, Masalu N, Kawira E, Magatti J, Kinyera T, Otim I, Legason ID, Nabalende H, Dhudha H, Ally H, Genga IO, Mumia M, Ayers LW, Pfeiffer RM, Biggar RJ, Bhatia K, Goedert JJ, and Mbulaiteye SM
- Subjects
- Adolescent, Burkitt Lymphoma etiology, Case-Control Studies, Child, Child, Preschool, Female, HIV Seropositivity complications, Humans, Infant, Infant, Newborn, Kenya epidemiology, Malaria complications, Malaria diagnosis, Male, Prevalence, Risk Factors, Surveys and Questionnaires statistics & numerical data, Tanzania epidemiology, Uganda epidemiology, Burkitt Lymphoma epidemiology, Endemic Diseases statistics & numerical data, HIV Seropositivity epidemiology, Malaria epidemiology, Socioeconomic Factors
- Abstract
Endemic Burkitt lymphoma (eBL) is the most common childhood cancer in sub-Saharan African countries, however, few epidemiologic studies have been undertaken and none attempted enrolling cases from multiple countries. We therefore conducted a population-based case-control study of eBL in children aged 0-15 years old in six regions in Northern Uganda, Northern Tanzania and Western Kenya, enrolling 862 suspected cases and 2,934 population controls (response rates 98.5-100%), and processing ~40,000 vials of samples using standardized protocols. Risk factor questionnaires were administered, and malaria period prevalence was measured using rapid diagnostic tests (RDTs). A total of 80.9% of the recruited cases were diagnosed as eBL; 61.4% confirmed by histology. Associations with eBL risk were computed using logistic regression models adjusted for relevant confounders. Associations common in at least two countries were emphasized. eBL risk was decreased with higher maternal income and paternal education and elevated with history of inpatient malaria treatment >12 months before enrollment. Reporting malaria-attributed fever up to 6 months before enrollment and malaria-RDT positivity at enrollment were associated with decreased eBL risk. Conversely, reporting exposure to mass malaria suppression programs (e.g., indoor residual insecticide) was associated with elevated risk. HIV seropositivity was associated with elevated eBL risk, but the relative impact was small. The study shows that it is feasible to conduct networked, multisite population-based studies of eBL in Africa. eBL was inversely associated with socioeconomic status, positively associated with inpatient malaria treatment 12 months ago and with living in areas targeted for malaria suppression, which support a role of malaria in eBL., (© 2019 UICC.)
- Published
- 2020
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27. Genome-wide discovery of somatic coding and noncoding mutations in pediatric endemic and sporadic Burkitt lymphoma.
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Grande BM, Gerhard DS, Jiang A, Griner NB, Abramson JS, Alexander TB, Allen H, Ayers LW, Bethony JM, Bhatia K, Bowen J, Casper C, Choi JK, Culibrk L, Davidsen TM, Dyer MA, Gastier-Foster JM, Gesuwan P, Greiner TC, Gross TG, Hanf B, Harris NL, He Y, Irvin JD, Jaffe ES, Jones SJM, Kerchan P, Knoetze N, Leal FE, Lichtenberg TM, Ma Y, Martin JP, Martin MR, Mbulaiteye SM, Mullighan CG, Mungall AJ, Namirembe C, Novik K, Noy A, Ogwang MD, Omoding A, Orem J, Reynolds SJ, Rushton CK, Sandlund JT, Schmitz R, Taylor C, Wilson WH, Wright GW, Zhao EY, Marra MA, Morin RD, and Staudt LM
- Subjects
- Adolescent, Adult, Burkitt Lymphoma pathology, Burkitt Lymphoma virology, Child, Child, Preschool, Cohort Studies, Cytidine Deaminase genetics, Epstein-Barr Virus Infections genetics, Epstein-Barr Virus Infections virology, Female, Follow-Up Studies, Herpesvirus 4, Human isolation & purification, Humans, Infant, Infant, Newborn, Male, Phenotype, Prognosis, Young Adult, Biomarkers, Tumor genetics, Burkitt Lymphoma genetics, Epstein-Barr Virus Infections complications, Genes, Immunoglobulin, Genome, Human, Mutation, Transcriptome
- Abstract
Although generally curable with intensive chemotherapy in resource-rich settings, Burkitt lymphoma (BL) remains a deadly disease in older patients and in sub-Saharan Africa. Epstein-Barr virus (EBV) positivity is a feature in more than 90% of cases in malaria-endemic regions, and up to 30% elsewhere. However, the molecular features of BL have not been comprehensively evaluated when taking into account tumor EBV status or geographic origin. Through an integrative analysis of whole-genome and transcriptome data, we show a striking genome-wide increase in aberrant somatic hypermutation in EBV-positive tumors, supporting a link between EBV and activation-induced cytidine deaminase (AICDA) activity. In addition to identifying novel candidate BL genes such as SIN3A , USP7 , and CHD8 , we demonstrate that EBV-positive tumors had significantly fewer driver mutations, especially among genes with roles in apoptosis. We also found immunoglobulin variable region genes that were disproportionally used to encode clonal B-cell receptors (BCRs) in the tumors. These include IGHV4-34, known to produce autoreactive antibodies, and IGKV3-20, a feature described in other B-cell malignancies but not yet in BL. Our results suggest that tumor EBV status defines a specific BL phenotype irrespective of geographic origin, with particular molecular properties and distinct pathogenic mechanisms. The novel mutation patterns identified here imply rational use of DNA-damaging chemotherapy in some patients with BL and targeted agents such as the CDK4/6 inhibitor palbociclib in others, whereas the importance of BCR signaling in BL strengthens the potential benefit of inhibitors for PI3K, Syk, and Src family kinases among these patients., (© 2019 by The American Society of Hematology.)
- Published
- 2019
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28. Associations between IgG reactivity to Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) antigens and Burkitt lymphoma in Ghana and Uganda case-control studies.
- Author
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Derkach A, Otim I, Pfeiffer RM, Onabajo OO, Legason ID, Nabalende H, Ogwang MD, Kerchan P, Talisuna AO, Ayers LW, Reynolds SJ, Nkrumah F, Neequaye J, Bhatia K, Theander TG, Prokunina-Olsson L, Turner L, Goedert JJ, Lavstsen T, and Mbulaiteye SM
- Subjects
- Adolescent, Antibodies, Protozoan metabolism, Binding Sites, Burkitt Lymphoma immunology, Case-Control Studies, Child, Child, Preschool, Female, Ghana, Humans, Infant, Infant, Newborn, Logistic Models, Male, Odds Ratio, Plasmodium falciparum immunology, Protozoan Proteins chemistry, Uganda, Burkitt Lymphoma parasitology, Immunoglobulin G metabolism, Malaria, Falciparum immunology, Plasmodium falciparum metabolism, Protozoan Proteins immunology
- Abstract
Background: Endemic Burkitt lymphoma (eBL) is an aggressive childhood B-cell lymphoma linked to Plasmodium falciparum (Pf) malaria in sub-Saharan Africa. We investigated antibody reactivity to several human receptor-binding domains of the Pf erythrocyte membrane protein 1 (PfEMP1) that play a key role in malaria pathogenesis and are targets of acquired immunity to malaria., Methods: Serum/plasma IgG antibody reactivity was measured to 22 Pf antigens, including 18 to PfEMP1 CIDR domains between cases and controls from two populations (149 eBL cases and 150 controls from Ghana and 194 eBL cases and 600 controls from Uganda). Adjusted odds ratios (aORs) for case-control associations were estimated by logistic regression., Findings: There was stronger reactivity to the severe malaria associated CIDRα1 domains than other CIDR domains both in cases and controls. eBL cases reacted to fewer antigens than controls (Ghana: p = 0·001; Uganda: p = 0·03), with statistically significant lower ORs associated with reactivity to 13+ antigens in Ghana (aOR 0·39, 95% CI 0·24-0·63; p
heterogeneity = 0·00011) and Uganda (aOR 0·60, 95% CI 0.41-0·88; pheterogeneity = 0·008). eBL was inversely associated with reactivity, coded as quartiles, to group A variant CIDRδ1 (ptrend = 0·035) in Ghana and group B CD36-binding variants CIDRα2·2 (ptrend = 0·006) and CIDRα2·4 (ptrend = 0·033) in Uganda, and positively associated with reactivity to SERA5 in Ghana (ptrend = 0·017) and Uganda (ptrend = 0·007) and group A CIDRα1·5 variant in Uganda only (ptrend = 0·034)., Interpretation: eBL cases reacted to fewer antigens than controls using samples from two populations, Ghana and Uganda. Attenuated humoral immunity to Pf EMP1 may contribute to susceptibility to low-grade malaria and eBL risk., Funding: Intramural Research Program, National Cancer Institute and National Institute of Allergy and Infectious Diseases, National Institutes of Health, Department of Health and Human Services., (Published by Elsevier B.V.)- Published
- 2019
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29. Acceptable Weight Ranges for Research Tissue Procurement and Biorepositories, 2015-2017.
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Nohle DG, Mandt RL, Couce ME, Parwani AV, and Ayers LW
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- Female, Humans, Male, Organ Size, Tissue and Organ Procurement standards, United States, Tissue Banks standards, Tissue Banks supply & distribution, Tissue and Organ Procurement methods
- Abstract
Background: The Cooperative Human Tissue Network, Midwestern Division, is a National Cancer Institute-funded program that provides quality research biospecimens to qualified investigators. Consented human tissues are procured according to researcher specifications for weight (size) and preservation type; weights of samples in significant demand and limited supply are negotiated. Weights of procured tissues are entered into a dedicated biospecimen database. This study seeks to provide guidance for acceptable tissue weights for researchers. Methods: Tissue weights by year and anatomic site were retrieved from the database for primary malignant tissues. The total number of tissues included was 5141. Statistical evaluation of data included the number of tissues for each year, anatomic site as well as minimum, maximum, average weights, standard deviation, and standard error. Anatomic sites with few tissues were excluded. Results: "Stock price" type graphs were constructed to show an average as "volume" with both full weight ranges and range that accommodated 80% of tissues. Average weight and number of sample trends varied by anatomic site. Tissues fell into four weight groups; 10 and 90 percentile boundaries were calculated for each. Smallest average research tissue weights for middle 80% were recorded for prostate and oropharynx (140 mg). Second weight group included tonsil, thyroid, breast, oral cavity, larynx, pancreas, salivary gland, skin, tongue, lung, and parotid (265 mg). The third group included stomach, cervix, colon, esophagus, endometrium, bone, brain, bladder, small bowel, uterus, liver, kidney lymph node, adrenal, and ovary (513 mg). The fourth and heaviest weight group included soft tissue tumors and spleen (1201 mg). Conclusions: Since tissue weights are not usually included in recommendations for research tissue procurement or for frozen tissues stored in biorepositories, we offer this data as a practical guide to researcher acceptable tissue weights for selected sites based on a 3-year researcher request and acceptance history.
- Published
- 2018
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30. Mast Cell Activation and KSHV Infection in Kaposi Sarcoma.
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Ayers LW, Barbachano-Guerrero A, McAllister SC, Ritchie JA, Asiago-Reddy E, Bartlett LC, Cesarman E, Wang D, Rochford R, Martin JN, and King CA
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers, Cytokines metabolism, Disease Susceptibility, Female, Humans, Immunohistochemistry, Male, Mast Cells metabolism, Methylhistamines metabolism, Middle Aged, Models, Biological, Sarcoma, Kaposi metabolism, Sarcoma, Kaposi pathology, Skin metabolism, Skin pathology, Tryptases metabolism, Herpesviridae Infections complications, Herpesviridae Infections virology, Herpesvirus 8, Human, Mast Cells immunology, Sarcoma, Kaposi etiology
- Abstract
Purpose: Kaposi sarcoma (KS) is a vascular tumor initiated by infection of endothelial cells (ECs) with KS-associated herpesvirus (KSHV). KS is dependent on sustained proinflammatory signals provided by intralesional leukocytes and continued infection of new ECs. However, the sources of these cytokines and infectious virus within lesions are not fully understood. Here, mast cells (MCs) are identified as proinflammatory cells within KS lesions that are permissive for, and activated by, infection with KSHV. Experimental Design: Three validated MC lines were used to assess permissivity of MCs to infection with KSHV and to evaluate MCs activation following infection. Biopsies from 31 AIDS-KS cases and 11 AIDS controls were evaluated by IHC for the presence of MCs in KS lesions and assessment of MC activation state and infection with KSHV. Plasma samples from 26 AIDS-KS, 13 classic KS, and 13 healthy adults were evaluated for levels of MC granule contents tryptase and histamine. Results: In culture, MCs supported latent and lytic KSHV infection, and infection-induced MC degranulation. Within KS lesions, MCs were closely associated with spindle cells. Furthermore, MC activation was extensive within patients with KS, reflected by elevated circulating levels of tryptase and a histamine metabolite. One patient with clinical signs of extensive MC activation was treated with antagonists of MC proinflammatory mediators, which resulted in a rapid and durable regression of AIDS-KS lesions. Conclusions: Using complimentary in vitro and in vivo studies we identify MCs as a potential long-lived reservoir for KSHV and a source of proinflammatory mediators within the KS lesional microenvironment. In addition, we identify MC antagonists as a promising novel therapeutic approach for KS. Clin Cancer Res; 24(20); 5085-97. ©2018 AACR ., (©2018 American Association for Cancer Research.)
- Published
- 2018
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31. Evaluating the Causal Link Between Malaria Infection and Endemic Burkitt Lymphoma in Northern Uganda: A Mendelian Randomization Study.
- Author
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Legason ID, Pfeiffer RM, Udquim KI, Bergen AW, Gouveia MH, Kirimunda S, Otim I, Karlins E, Kerchan P, Nabalende H, Bayanjargal A, Emmanuel B, Kagwa P, Talisuna AO, Bhatia K, Yeager M, Biggar RJ, Ayers LW, Reynolds SJ, Goedert JJ, Ogwang MD, Fraumeni JF Jr, Prokunina-Olsson L, and Mbulaiteye SM
- Subjects
- Adolescent, Burkitt Lymphoma complications, Burkitt Lymphoma epidemiology, Burkitt Lymphoma parasitology, Child, Child, Preschool, Female, Genetic Association Studies, Genotype, Humans, Infant, Infant, Newborn, Malaria, Falciparum complications, Malaria, Falciparum epidemiology, Malaria, Falciparum parasitology, Male, Plasmodium falciparum pathogenicity, Uganda epidemiology, Burkitt Lymphoma genetics, Genetic Predisposition to Disease, Malaria, Falciparum genetics, Mendelian Randomization Analysis
- Abstract
Background: Plasmodium falciparum (Pf) malaria infection is suspected to cause endemic Burkitt Lymphoma (eBL), but the evidence remains unsettled. An inverse relationship between sickle cell trait (SCT) and eBL, which supports that between malaria and eBL, has been reported before, but in small studies with low power. We investigated this hypothesis in children in a population-based study in northern Uganda using Mendelian Randomization., Methods: Malaria-related polymorphisms (SCT, IL10, IL1A, CD36, SEMA3C, and IFNAR1) were genotyped in 202 eBL cases and 624 controls enrolled during 2010-2015. We modeled associations between genotypes and eBL or malaria using logistic regression., Findings: SCT was associated with decreased risk of eBL (adjusted odds ratio [OR] 0·37, 95% CI 0·21-0·66; p=0·0003). Decreased risk of eBL was associated with IL10 rs1800896-CT (OR 0·73, 95% CI 0·50-1·07) and -CC genotypes (OR 0·53, 95% CI 0·29-0·95, p
trend =0·019); IL1A rs2856838-AG (OR 0·56, 95% CI 0·39-0·81) and -AA genotype (OR 0·50, 95% CI 0·28-1·01, ptrend =0·0016); and SEMA3C rs4461841-CT or -CC genotypes (OR 0·57, 95% CI 0·35-0·93, p=0·0193). SCT and IL10 rs1800896, IL1A rs2856838, but not SEMA3C rs4461841, polymorphisms were associated with decreased risk of malaria in the controls., Interpretation: Our results support a causal effect of malaria infection on eBL., (Published by Elsevier B.V.)- Published
- 2017
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32. Burkitt lymphoma expresses oncofetal chondroitin sulfate without being a reservoir for placental malaria sequestration.
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Agerbaek MØ, Pereira MA, Clausen TM, Pehrson C, Oo HZ, Spliid C, Rich JR, Fung V, Nkrumah F, Neequaye J, Biggar RJ, Reynolds SJ, Tosato G, Pullarkat ST, Ayers LW, Theander TG, Daugaard M, Bhatia K, Nielsen MA, Mbulaiteye SM, and Salanti A
- Subjects
- Adolescent, Antibodies, Protozoan blood, Antigens, Protozoan immunology, Burkitt Lymphoma parasitology, Cell Line, Tumor, Child, Child, Preschool, Erythrocytes parasitology, Female, Humans, Immunoglobulin G metabolism, Malaria, Falciparum complications, Male, Plasmodium falciparum immunology, Pregnancy, Proteoglycans metabolism, Recombinant Proteins metabolism, Antigens, Neoplasm metabolism, Burkitt Lymphoma metabolism, Chondroitin Sulfates metabolism, Malaria, Falciparum metabolism, Placenta metabolism, Placenta parasitology
- Abstract
Burkitt lymphoma (BL) is a malignant disease, which is frequently found in areas with holoendemic Plasmodium falciparum malaria. We have previously found that the VAR2CSA protein is present on malaria-infected erythrocytes and facilitates a highly specific binding to the placenta. ofCS is absent in other non-malignant tissues and thus VAR2CSA generally facilitates parasite sequestration and accumulation in pregnant women. In this study, we show that the specific receptor for VAR2CSA, the oncofetal chondroitin sulfate (ofCS), is likewise present in BL tissue and cell lines. We therefore explored whether ofCS in BL could act as anchor site for VAR2CSA-expressing infected erythrocytes. In contrast to the placenta, we found no evidence of in vivo sequestering of infected erythrocytes in the BL tissue. Furthermore, we found VAR2CSA-specific antibody titers in children with endemic BL to be lower than in control children from the same malaria endemic region. The abundant presence of ofCS in BL tissue and the absence of ofCS in non-malignant tissue encouraged us to examine whether recombinant VAR2CSA could be used to target BL. We confirmed the binding of VAR2CSA to BL-derived cells and showed that a VAR2CSA drug conjugate efficiently killed the BL-derived cell lines in vitro. These results identify ofCS as a novel therapeutic BL target and highlight how VAR2CSA could be used as a tool for the discovery of novel approaches for directing BL therapy., (© 2016 UICC.)
- Published
- 2017
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33. Changes in dam and pup behavior following repeated postnatal exposure to a predator odor (TMT): A preliminary investigation in Long-Evans rats.
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Ayers LW, Asok A, Blaze J, Roth TL, and Rosen JB
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- Animals, Animals, Newborn, Butyric Acid, Female, Male, Rats, Rats, Long-Evans, Thiazoles, Water, Behavior, Animal physiology, Cues, Fear physiology, Freezing Reaction, Cataleptic physiology, Maternal Behavior physiology, Odorants, Vocalization, Animal physiology
- Abstract
The present study investigated whether repeated early postnatal exposure to the predator odor 2,5-dihydro-2,4,5-trimethylthiazoline (TMT) alters behavioral responses to the stimulus later in life, at postnatal day (PN30). Long-Evans rat pups with their mothers were exposed for 20 min daily to TMT, water, or a noxious odor, butyric acid (BTA), during the first three weeks of life. Mothers exposed to TMT displayed more crouching and nursing behavior than those exposed to BTA, and TMT exposed pups emitted more ultrasonic vocalizations than BTA exposed pups. At PN30, rats were tested for freezing to TMT, water, or BTA. Rats exposed to TMT during the postnatal period displayed less freezing to TMT than rats exposed postnatally to water or BTA. Our data indicate that early-life experience with a predator cue has a significant impact on later fear responses to that same cue, highlighting the programming capacity of the postnatal environment on the development of behavior., (© 2015 Wiley Periodicals, Inc.)
- Published
- 2016
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34. EBV-Positive Grey Zone Lymphoma in an HIV Infected Man from Kampala, Uganda: Case Report.
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Tumwine LK, Orem J, and Ayers LW
- Abstract
Aim: We describe the clinical, histopathological and immunophenotypic characteristics of an HIV-infected adult man on antiretroviral therapy who presented with an EBV-positive grey zone lymphoma., Case Presentation: A 56-year-old HIV infected man from Uganda presented with a four month history of progressive abdominal swelling and B-symptoms. He was on highly active antiretroviral therapy (HAART) and cotrimoxazole. He was afebrile (36.9°C), severely wasted (BMI 14.8), and mildly anaemic. On physical examination, he had a 15 by 8 cm mass in the hypogastrium and umbilical region. The total white cell count was 8.3×10
3 /μL; neutrophils, 5.72×103 /μL; haemoglobin 11.1g/dL, platelets 528×103 /μL, LDH 197 IU/L and CD4 367/μL. Abdominal ultrasound and CT scan showed a tumour involving the mesentery, jejunum and mid ileum. At laparotomy, a biopsy was taken, fixed, processed and stained with Haematoxylin & Eosin (H & E). Histopathology demonstrated large pleomorphic cells admixed with inflammatory smaller cells, Reed-Sternberg-like cell variants and frequent abnormal mitoses. Biomarkers CD20, PAX5, CD30 were positive but ALK negative (immunohistochemistry and strong EBER positivity in situ hybridization. The patient improved on modified CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) therapy., Discussion: The tumour had features intermediate between mediastinal large B cell lymphoma and classical Hodgkin lymphoma., Conclusion: We present a case of EBV-positive grey zone lymphoma in an HIV-infected man on HAART therapy diagnosed and treated in a resource constrained medical setting. The histological features are unusual and represent a low incidence lymphoma that is recognized by mixed features reminiscent of Hodgkin's lymphoma and mediastinal large B-cell lymphoma.- Published
- 2014
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35. Developing clinical strength-of-evidence approach to define HIV-associated malignancies for cancer registration in Kenya.
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Korir A, Mauti N, Moats P, Gurka MJ, Mutuma G, Metheny C, Mwamba PM, Oyiro PO, Fisher M, Ayers LW, Rochford R, Mwanda WO, and Remick SC
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Child, Evidence-Based Practice, Female, HIV Infections epidemiology, Humans, Kenya epidemiology, Male, Middle Aged, Pilot Projects, Prevalence, Registries, Sarcoma, Kaposi epidemiology, Uterine Cervical Neoplasms epidemiology, Young Adult, HIV Infections complications, Sarcoma, Kaposi virology, Uterine Cervical Neoplasms virology
- Abstract
Background: Sub-Saharan Africa cancer registries are beset by an increasing cancer burden further exacerbated by the AIDS epidemic where there are limited capabilities for cancer-AIDS match co-registration. We undertook a pilot study based on a "strength-of-evidence" approach using clinical data that is abstracted at the time of cancer registration for purposes of linking cancer diagnosis to AIDS diagnosis., Methods/findings: The standard Nairobi Cancer Registry form was modified for registrars to abstract the following clinical data from medical records regarding HIV infection/AIDS in a hierarchal approach at time of cancer registration from highest-to-lowest strength-of-evidence: 1) documentation of positive HIV serology; 2) antiretroviral drug prescription; 3) CD4+ lymphocyte count; and 4) WHO HIV clinical stage or immune suppression syndrome (ISS), which is Kenyan terminology for AIDS. Between August 1 and October 31, 2011 a total of 1,200 cancer cases were registered. Of these, 171 cases (14.3%) met clinical strength-of-evidence criteria for association with HIV infection/AIDS; 69% (118 cases were tumor types with known HIV association - Kaposi's sarcoma, cervical cancer, non-Hodgkin's and Hodgkin's lymphoma, and conjunctiva carcinoma) and 31% (53) were consistent with non-AIDS defining cancers. Verifiable positive HIV serology was identified in 47 (27%) cases for an absolute seroprevalence rate of 4% among the cancer registered cases with an upper boundary of 14% among those meeting at least one of strength-of-evidence criteria., Conclusions/significance: This pilot demonstration of a hierarchal, clinical strength-of-evidence approach for cancer-AIDS registration in Kenya establishes feasibility, is readily adaptable, pragmatic, and does not require additional resources for critically under staffed cancer registries. Cancer is an emerging public health challenge, and African nations need to develop well designed population-based studies in order to better define the impact and spectrum of malignant disease in the backdrop of HIV infection.
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- 2014
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36. EPSTEIN -BARR VIRUS ASSOCIATION WITH MALIGNANT LYMPHOMA SUBGROUPS IN ZARIA, NIGERIA.
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Iliyasu Y, Ayers LW, Liman AA, Waziri GD, and Shehu SM
- Abstract
Epstein-Barr virus (EBV) is said to infect more than 90% of humans worldwide with latent infection for life. A recognized carcinogen, EBV is linked to malignant lymphoma (ML) subtypes of Burkitt's lymphoma (BL), plasmablastic lymphoma, diffuse large cell lymphoma (DLBCL) and Hodgkin's lymphoma (HL). We report the association of EBV with ML in a segment of our patient population. Paraffin blocks from the archives of ABUTH, Zaria were used to construct tissue microarray sections stained using 30 monoclonal antibodies for common Non-Hodgkin's lymphoma/ Hodgkin's lymphoma antigen and chromogenic in situ hybridization (CISH) for EBV-encoded RNA were done. Fewer associations of ML with EBV were found than reported from elsewhere in Africa.
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- 2014
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37. Protein arginine methyltransferase 5 (PRMT5) inhibition induces lymphoma cell death through reactivation of the retinoblastoma tumor suppressor pathway and polycomb repressor complex 2 (PRC2) silencing.
- Author
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Chung J, Karkhanis V, Tae S, Yan F, Smith P, Ayers LW, Agostinelli C, Pileri S, Denis GV, Baiocchi RA, and Sif S
- Subjects
- Animals, Cell Death, Cell Line, Tumor, Cyclin D1 metabolism, Epigenesis, Genetic, Gene Knockdown Techniques, Genes, Retinoblastoma, Histone Deacetylase 2 genetics, Histone Deacetylase 2 metabolism, Humans, Lymphoma pathology, Lymphoma, Non-Hodgkin genetics, Lymphoma, Non-Hodgkin metabolism, Lymphoma, Non-Hodgkin pathology, Mice, Polycomb Repressive Complex 2 antagonists & inhibitors, Promoter Regions, Genetic, Retinoblastoma-Like Protein p130 genetics, Retinoblastoma-Like Protein p130 metabolism, Signal Transduction, Tumor Cells, Cultured, Lymphoma genetics, Lymphoma metabolism, Polycomb Repressive Complex 2 genetics, Protein Methyltransferases antagonists & inhibitors, Protein Methyltransferases genetics, Protein-Arginine N-Methyltransferases antagonists & inhibitors, Protein-Arginine N-Methyltransferases genetics, Retinoblastoma Protein metabolism
- Abstract
Epigenetic regulation mediated by lysine- and arginine-specific enzymes plays an essential role in tumorigenesis, and enhanced expression of the type II protein arginine methyltransferase PRMT5 as well as the polycomb repressor complex PRC2 has been associated with increased cell proliferation and survival. Here, we show that PRMT5 is overexpressed in three different types of non-Hodgkin lymphoma cell lines and clinical samples as well as in mouse primary lymphoma cells and that it up-regulates PRC2 expression through inactivation of the retinoblastoma proteins RB1 and RBL2. Although PRMT5 epigenetically controls RBL2 expression, it indirectly promotes RB1 phosphorylation through enhanced cyclin D1 expression. Furthermore, we demonstrate that PRMT5 knockdown in non-Hodgkin lymphoma cell lines and mouse primary lymphoma cells leads to RBL2 derepression and RB1 reactivation, which in turn inhibit PRC2 expression and trigger derepression of its CASP10, DAP1, HOXA5, and HRK pro-apoptotic target genes. We also show that reduced PRMT5 expression leads to cyclin D1 transcriptional repression via loss of TP53K372 methylation, which results in decreased BCL3 expression and enhanced recruitment of NF-κB p52-HDAC1 repressor complexes to the cyclin D1 promoter. These findings indicate that PRMT5 is a master epigenetic regulator that governs expression of its own target genes and those regulated by PRC2 and that its inhibition could offer a promising therapeutic strategy for lymphoma patients.
- Published
- 2013
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38. MicroRNA-31 predicts the presence of lymph node metastases and survival in patients with lung adenocarcinoma.
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Meng W, Ye Z, Cui R, Perry J, Dedousi-Huebner V, Huebner A, Wang Y, Li B, Volinia S, Nakanishi H, Kim T, Suh SS, Ayers LW, Ross P, Croce CM, Chakravarti A, Jin VX, and Lautenschlaeger T
- Subjects
- Adenocarcinoma mortality, Adenocarcinoma of Lung, Aged, Aged, 80 and over, Cell Line, Tumor, DNA Methylation, Female, Gene Expression, Gene Expression Profiling, Genetic Vectors genetics, Humans, Lentivirus genetics, Lung Neoplasms mortality, Lymphatic Metastasis, Male, Middle Aged, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3 metabolism, Neoplasm Staging, Prognosis, Promoter Regions, Genetic, Reproducibility of Results, Risk Factors, Signal Transduction, Adenocarcinoma genetics, Adenocarcinoma pathology, Lung Neoplasms genetics, Lung Neoplasms pathology, Lymph Nodes pathology, MicroRNAs genetics
- Abstract
Purpose: We conducted genome-wide miRNA-sequencing (miRNA-seq) in primary cancer tissue from patients of lung adenocarcinoma to identify markers for the presence of lymph node metastasis., Experimental Design: Markers for lymph node metastasis identified by sequencing were validated in a separate cohort using quantitative PCR. After additional validation in the The Cancer Genome Atlas (TCGA) dataset, functional characterization studies were conducted in vitro., Results: MiR-31 was upregulated in lung adenocarcinoma tissues from patients with lymph node metastases compared with those without lymph node metastases. We confirmed miR-31 to be upregulated in lymph node-positive patients in a separate patient cohort (P = 0.009, t test), and to be expressed at higher levels in adenocarcinoma tissue than in matched normal adjacent lung tissues (P < 0.0001, paired t test). MiR-31 was then validated as a marker for lymph node metastasis in an external validation cohort of 233 lung adenocarcinoma cases of the TCGA (P = 0.031, t test). In vitro functional assays showed that miR-31 increases cell migration, invasion, and proliferation in an ERK1/2 signaling-dependent manner. Notably, miR-31 was a significant predictor of survival in a multivariate cox regression model even when controlling for cancer staging. Exploratory in silico analysis showed that low expression of miR-31 is associated with excellent survival for T2N0 patients., Conclusions: We applied miRNA-seq to study microRNomes in lung adenocarcinoma tissue samples for the first time and potentially identified a miRNA predicting the presence of lymph node metastasis and survival outcomes in patients of lung adenocarcinoma., (©2013 AACR.)
- Published
- 2013
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39. Freezing to the predator odor 2,4,5 dihydro 2,5 trimethylthiazoline (TMT) is disrupted by olfactory bulb removal but not trigeminal deafferentation.
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Ayers LW, Asok A, Heyward FD, and Rosen JB
- Subjects
- Animals, Butyric Acid pharmacology, Denervation, Fear physiology, Male, Motor Activity drug effects, Predatory Behavior, Psychomotor Performance drug effects, Psychomotor Performance physiology, Rats, Rats, Sprague-Dawley, Behavior, Animal physiology, Freezing Reaction, Cataleptic drug effects, Neurons, Afferent physiology, Odorants, Olfactory Bulb physiology, Thiazoles pharmacology, Trigeminal Nerve physiology
- Abstract
2,4,5 dihydro 2,5 trimethylthiazoline (TMT) is a synthesized component of red fox anal secretions that reliably elicits defensive behaviors in rats and mice. TMT differs from other predator odors because it is a single molecule, it can be synthesized in large quantities, and the dose for exposure is highly controllable in an experimental setting. TMT has become a popular tool for studying the brain mechanisms that mediate innate fear behavior to olfactory stimuli. However, this view of TMT as a biologically relevant olfactory stimulus has been challenged by suggestions that the odor elicits fear behavior due to its irritating properties, presumably working through a nociceptive mechanism. To address this criticism our lab measured freezing behavior in rats during exposures to 2 odors (TMT and butyric acid) and H2O (no odor control) following either surgical transection of the trigeminal nerves or ablation of the olfactory bulbs. Our findings (Experiment 1) indicate that freezing behavior to TMT requires an intact olfactory system, as indicated by the loss of freezing following olfactory bulb removal. Experiment 2 revealed that rats with trigeminal nerve transection freeze normally to TMT, suggesting the olfactory system mediates this behavior to TMT. A replication of Experiment 1 that included contextual fear conditioning revealed that the decreased freezing behavior was not due to an inability of olfactory bulb ablated rats to freeze (Experiment 3). Taken together, these findings support TMT's role as an ecologically relevant predator odor useful in experiments of unconditioned fear that is mediated via olfaction and not nociception., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
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40. Immediate early gene and neuropeptide expression following exposure to the predator odor 2,5-dihydro-2,4,5-trimethylthiazoline (TMT).
- Author
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Asok A, Ayers LW, Awoyemi B, Schulkin J, and Rosen JB
- Subjects
- Animals, Behavior, Animal, Brain metabolism, Male, Neuropeptides metabolism, Proto-Oncogene Proteins c-fos metabolism, Rats, Rats, Sprague-Dawley, Brain drug effects, Fear drug effects, Genes, Immediate-Early drug effects, Neuropeptides drug effects, Thiazoles pharmacology
- Abstract
The immediate early gene c-fos and a number of neuropeptides have been widely used to help delineate the neural circuitry of innate fear to predator odors. The present study used in situ hybridization techniques to examine the expression of the immediate early gene transcription factors c-fos and egr-1, and the neuropeptides corticotropin-releasing hormone (crh) and enkephalin (enk) following exposure to the predator odor 2,5-dihydro-2,4,5-trimethylthiazoline (TMT). Rats were exposed to water (H2O), TMT, or the irritating odor butyric acid (BA) and freezing was used to measure fear behavior. Changes in gene expression were analyzed in the medial prefrontal cortex (mPFC), the bed nucleus of the stria terminalis (BNST), paraventricular nucleus of the hypothalamus (PVN), and central nucleus of the amygdala (CeA). Animals froze more to TMT than BA and H2O, and more to BA than H2O. Compared to H2O and BA, c-fos and egr-1 were elevated within the BNST, PVN, and CeA in rats exposed to TMT, but not the mPFC. Crh was also elevated in rats exposed to TMT within the CeA and PVN, but not the BNST or mPFC. Enk was elevated within the PVN in TMT and BA exposed rats compared to H2O exposure. These data indicate that exposure to the predator odor TMT induces similar expression patterns for c-fos and egr-1, but different patterns for crh and enk, with partial overlap of the immediate-early genes and neuropeptides within specific brain regions., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
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41. Comparison of microRNA deep sequencing of matched formalin-fixed paraffin-embedded and fresh frozen cancer tissues.
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Meng W, McElroy JP, Volinia S, Palatini J, Warner S, Ayers LW, Palanichamy K, Chakravarti A, and Lautenschlaeger T
- Subjects
- Adult, Aged, Female, Humans, In Vitro Techniques, Male, Middle Aged, Cryopreservation methods, Formaldehyde chemistry, Gene Expression Profiling methods, High-Throughput Nucleotide Sequencing methods, MicroRNAs genetics, Paraffin Embedding methods, Tissue Fixation methods
- Abstract
MicroRNAs regulate several aspects of tumorigenesis and cancer progression. Most cancer tissues are archived formalin-fixed and paraffin-embedded (FFPE). While microRNAs are a more stable form of RNA thought to withstand FFPE-processing and degradation there is only limited evidence for the latter assumption. We examined whether microRNA profiling can be successfully conducted on FFPE cancer tissues using SOLiD ligation based sequencing. Tissue storage times (2-9 years) appeared to not affect the number of detected microRNAs in FFPE samples compared to matched frozen samples (paired t-test p>0.7). Correlations of microRNA expression values were very high across microRNAs in a given sample (Pearson's r = 0.71-0.95). Higher variance of expression values among samples was associated with higher correlation coefficients between FFPE and frozen tissues. One of the FFPE samples in this study was degraded for unknown reasons with a peak read length of 17 nucleotides compared to 21 in all other samples. The number of detected microRNAs in this sample was within the range of microRNAs detected in all other samples. Ligation-based microRNA deep sequencing on FFPE cancer tissues is feasible and RNA degradation to the degree observed in our study appears to not affect the number of microRNAs that can be quantified.
- Published
- 2013
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42. Increased myocardial prevalence of C-reactive protein in human coronary heart disease: direct effects on microvessel density and endothelial cell survival.
- Author
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Joshi MS, Tong L, Cook AC, Schanbacher BL, Huang H, Han B, Ayers LW, and Bauer JA
- Subjects
- Adult, Antioxidants pharmacology, Apoptosis drug effects, C-Reactive Protein pharmacology, Cell Survival drug effects, Cells, Cultured, Coronary Disease metabolism, Coronary Vessels metabolism, Endothelium, Vascular metabolism, Human Umbilical Vein Endothelial Cells drug effects, Human Umbilical Vein Endothelial Cells pathology, Humans, Image Processing, Computer-Assisted, Microvessels metabolism, Myocardium metabolism, C-Reactive Protein metabolism, Coronary Disease pathology, Coronary Vessels pathology, Endothelium, Vascular pathology, Microvessels pathology, Myocardium pathology
- Abstract
Background: Elevated plasma C-reactive protein (CRP) is a biomarker of cardiovascular diseases (CVDs), but its potential roles as a participant of the disease process are not well defined. Although early endothelial cell injury and dysfunction are recognized events in CVD, the initiating events are not well established. Here we investigated the local myocardial CRP levels and cardiac microvessel densities in control and CVD tissue samples. Using in vitro methodologies, we investigated the direct effects of CRP on human endothelial cells., Methods: Cardiac specimens were collected at autopsy within 4 h of death and were classified as normal controls or documented evidence of CVD. The regional prevalence of CRP and the cardiac microvessels (<40 μm) were investigated using immunohistochemistry. For in vitro experiments, human umbilical vein endothelial cells were incubated with CRP. Intracellular oxidant levels were assessed using 2',7'-dichlorofluorescein diacetate fluorescence microscopy, and cell survival was concurrently determined. Effects of chemical antioxidants on endothelial cell survival were also tested., Results: Myocardial CRP levels were elevated in CVD specimens. This was associated with reduced cardiac microvessels, and this rarefaction was inversely correlated to adjacent myocardial CRP prevalence. CRP caused concentration-dependent increases in oxidant production and cell apoptosis., Conclusions: These findings provide evidence supporting myocardial CRP as a locally produced inflammatory marker and as a potential participant in endothelial toxicity and microvascular rarefaction., (Copyright © 2012 Elsevier Inc. All rights reserved.)
- Published
- 2012
- Full Text
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43. Oxytocin reduces background anxiety in a fear-potentiated startle paradigm: peripheral vs central administration.
- Author
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Ayers LW, Missig G, Schulkin J, and Rosen JB
- Subjects
- Acoustic Stimulation methods, Animals, Anxiety metabolism, Anxiety psychology, Fear physiology, Fear psychology, Infusions, Intraventricular, Infusions, Subcutaneous, Male, Rats, Rats, Sprague-Dawley, Reflex, Startle physiology, Anxiety drug therapy, Fear drug effects, Oxytocin administration & dosage, Reflex, Startle drug effects
- Abstract
Oxytocin is known to have anti-anxiety and anti-stress effects. Using a fear-potentiated startle paradigm in rats, we previously demonstrated that subcutaneously administered oxytocin suppressed acoustic startle following fear conditioning compared with startle before fear conditioning (termed background anxiety), but did not have an effect on cue-specific fear-potentiated startle. The findings suggest oxytocin reduces background anxiety, an anxious state not directly related to cue-specific fear, but sustained beyond the immediate threat. The goal of the present study was to compare the effects of centrally and peripherally administered oxytocin on background anxiety and cue-specific fear. Male rats were given oxytocin either subcutaneously (SC) or intracerebroventricularly (ICV) into the lateral ventricles before fear-potentiated startle testing. Oxytocin doses of 0.01 and 0.1 μg/kg SC reduced background anxiety. ICV administration of oxytocin at doses from 0.002 to 20 μg oxytocin had no effect on background anxiety or cue-specific fear-potentiated startle. The 20 μg ICV dose of oxytocin did reduce acoustic startle in non-fear conditioned rats. These studies indicate that oxytocin is potent and effective in reducing background anxiety when delivered peripherally, but not when delivered into the cerebroventricular system. Oxytocin given systemically may have anti-anxiety properties that are particularly germane to the hypervigilance and exaggerated startle typically seen in many anxiety and mental health disorder patients.
- Published
- 2011
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44. Impact of the HIV epidemic and Anti-Retroviral Treatment policy on lymphoma incidence and subtypes seen in the Western Cape of South Africa, 2002-2009: preliminary findings of the Tygerberg Lymphoma Study Group.
- Author
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Abayomi EA, Somers A, Grewal R, Sissolak G, Bassa F, Maartens D, Jacobs P, Stefan C, and Ayers LW
- Subjects
- Communicable Disease Control, Epidemics, HIV Infections complications, HIV Infections diagnosis, HIV Seropositivity drug therapy, Health Policy, Humans, Incidence, Public Health, South Africa, Anti-HIV Agents therapeutic use, HIV Infections epidemiology, Lymphoma drug therapy, Lymphoma virology
- Abstract
The Tygerberg Lymphoma Study Group was constituted in 2007 to quantify the impact of HIV on the pattern and burden of lymphoma cases in the Western Cape of South Africa which currently has an HIV prevalence of 15%. South Africa has had an Anti-Retroviral Treatment (ART) policy and a roll-out plan since 2004 attaining 31% effective coverage in 2009. This study is designed to qualify and establish the impact of HIV epidemic and the ARV roll-out treatment program on the incidence of HIV Related Lymphoma (HRL). Early data document that despite the ART roll out, cases of HRL are increasing in this geographical location, now accounting for 37% of all lymphomas seen in 2009 which is an increase from 5% in 2002. This is in contrast to trends seen in developed environments following the introduction of ART. Also noted are the emergence of subtypes not previously seen in this location such as Burkitt and plasmablastic lymphomas. Burkitt lymphoma is now the commonest HRL seen in this population followed by diffuse large B-cell lymphoma subtypes. The reasons for this observed increase in HRL are not ascribable to improved diagnostic capacity as the tertiary institute in which these diagnoses are made has had significant expertise in this regard for over a decade. We ascribe this paradoxical finding to an ART treatment environment that is ineffective for a diversity of reasons, paramount of which are poor coverage, late commencement of ART and incomplete viral suppression., (Copyright © 2011. Published by Elsevier Ltd.)
- Published
- 2011
- Full Text
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45. Accuracy of Burkitt lymphoma diagnosis in constrained pathology settings: importance to epidemiology.
- Author
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Ogwang MD, Zhao W, Ayers LW, and Mbulaiteye SM
- Subjects
- Burkitt Lymphoma epidemiology, Child, Developing Countries statistics & numerical data, Female, Humans, Male, Public Health, Referral and Consultation, Reproducibility of Results, Uganda epidemiology, Burkitt Lymphoma diagnosis, Health Services Accessibility
- Abstract
Context: Burkitt lymphoma (BL) is endemic in Uganda and because of the high incidence, diagnosis is often presumed during clinical care and epidemiologic studies., Objectives: To assess the accuracy of the clinical and the local pathology diagnosis of BL as assessed by an outside pathology review diagnosis and to understand the limitations on histopathology practice in a resource-constrained setting at 1 hospital in Uganda., Design: Clinically presumed pediatric (<15 years) BL cases with biopsies and pathology reports, from 1993 to 2007, were identified at St Mary's Hospital, Lacor (Gulu, Uganda). Local histopathology procedures, hematoxylin-eosin-stained tissue sections, and formalin-fixed paraffin-embedded blocks were reviewed onsite by an outside pathologist, followed by outside study that included tissue microarray immunohistochemistry and in situ hybridization., Results: Local pathology laboratory procedures were inconsistent and suboptimal, especially for tissue fixation. There were 88 clinically presumed BL cases. Sixty-three could be reviewed by outside pathology (25 cases of lost blocks or no remaining tumor) and showed a clinical diagnostic accuracy of 75% (47 confirmed of 63), with a possible range of 62% to 85%, depending on the actual diagnosis of the 25 nonevaluable cases. There were 64 BL cases diagnosed by local pathology. Forty-five could be reviewed by outside pathology (19 cases of lost blocks or no remaining tumor) and showed a local pathology diagnostic accuracy of 82% (37 confirmed of 45), with a possible range of 58% to 88%, depending on the actual diagnosis of the 19 nonevaluable cases. Non-BL diagnoses included other non-Hodgkin lymphomas, Hodgkin lymphoma, and benign infectious lymphadenopathy., Conclusions: Accuracy of clinical diagnosis of BL was reduced by inclusion of other diseases with similar clinical presentations. Local pathology, using morphology alone, only marginally improved clinical accuracy and often could not support outside pathology review due to inadequate laboratory procedures. There is an urgent need to improve pathology services in Uganda before conducting high-quality clinical and epidemiologic studies.
- Published
- 2011
- Full Text
- View/download PDF
46. The AIDS and Cancer Specimen Resource.
- Author
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Ayers LW, Silver S, Orenstein JM, McGrath MS, and Garcia DL
- Subjects
- Humans, Acquired Immunodeficiency Syndrome, Biological Specimen Banks, Neoplasms
- Abstract
The AIDS and Cancer Specimen Resource (ACSR) is a cooperative agreement among the United States National Cancer Institute (NCI) (Office of the Director, Office of HIV and AIDS Malignancy (OHAM)) and regional US consortia, University of California, San Francisco (West Coast), George Washington University (East Coast), and The Ohio State University (Mid-Region). The ACSR's main objective is to collect, preserve, and disperse HIV-related tissues and biologic fluids along with clinical data to qualified investigators with a focus on HIV/AIDS-related malignancies. The ACSR biorepository has more than 265,000 human HIV-positive and control samples available from 39 processing types, 16 specimen types, and 52 anatomical site types. These HIV-infected biological fluids and tissues are made available to funded approved investigators at no fee. Technical support such as HIV DNA identification in tissues and tissue microarray (TMA) blocks are available to assist approved investigators. Research needs may be filled through ACSR cooperative arrangements when not met by currently banked material. Those participating with the ACSR are expected to share their research findings with the scientific community. Some 117 abstract/poster and podium reports at national and international scientific meetings and 94 publications have been contributed to the scientific literature (as of 2010). Investigators can browse the ACSR Internet site at http://acsr.ucsf.edu for biospecimens to support their scientific initiatives, including basic, translational, biomarker discovery, and molecular epidemiology studies.
- Published
- 2011
- Full Text
- View/download PDF
47. Oxytocin reduces background anxiety in a fear-potentiated startle paradigm.
- Author
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Missig G, Ayers LW, Schulkin J, and Rosen JB
- Subjects
- Acoustic Stimulation psychology, Animals, Conditioning, Classical drug effects, Cues, Disease Models, Animal, Dose-Response Relationship, Drug, Male, Oxytocin administration & dosage, Photic Stimulation methods, Rats, Rats, Sprague-Dawley, Anxiety drug therapy, Fear psychology, Oxytocin pharmacology, Reflex, Startle drug effects
- Abstract
Oxytocin reportedly decreases anxious feelings in humans and may therefore have therapeutic value for anxiety disorders, such as post-traumatic stress disorder (PTSD). As PTSD patients have exaggerated startle responses, a fear-potentiated startle paradigm in rats may have face validity as an animal model to examine the efficacy of oxytocin in treating these symptoms. Oxytocin (0, 0.01, 0.1, or 1.0 μg, subcutaneously) was given either 30 min before fear conditioning, immediately after fear conditioning, or 30 min before fear-potentiated startle testing to assess its effects on acquisition, consolidation, and expression of conditioned fear, respectively. Startle both in the presence and absence of the fear-conditioned light was significantly diminished by oxytocin when administered at acquisition, consolidation, or expression. There was no specific effect of oxytocin on light fear-potentiated startle. In an additional experiment, oxytocin had no effects on acoustic startle without previous fear conditioning. Further, in a context-conditioned test, previous light-shock fear conditioning did not increase acoustic startle during testing when the fear-conditioned light was not presented. The data suggest that oxytocin did not diminish cue-specific conditioned nor contextually conditioned fear, but reduced background anxiety. This suggests that oxytocin has unique effects of decreasing background anxiety without affecting learning and memory of a specific traumatic event. Oxytocin may have antianxiety properties that are particularly germane to the hyper-vigilance and exaggerated startle typically seen in PTSD patients.
- Published
- 2010
- Full Text
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48. Immunological detection of viral large T antigen identifies a subset of Merkel cell carcinoma tumors with higher viral abundance and better clinical outcome.
- Author
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Bhatia K, Goedert JJ, Modali R, Preiss L, and Ayers LW
- Subjects
- Carcinoma, Merkel Cell immunology, Carcinoma, Merkel Cell therapy, Carcinoma, Merkel Cell virology, Humans, Polyomavirus immunology, Treatment Outcome, Viral Load, Antigens, Viral, Tumor analysis, Carcinoma, Merkel Cell diagnosis, Polyomavirus isolation & purification
- Published
- 2010
- Full Text
- View/download PDF
49. Merkel cell carcinoma subgroups by Merkel cell polyomavirus DNA relative abundance and oncogene expression.
- Author
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Bhatia K, Goedert JJ, Modali R, Preiss L, and Ayers LW
- Subjects
- Aged, Aged, 80 and over, Carcinoma, Merkel Cell classification, Carcinoma, Merkel Cell genetics, DNA Nucleotidylexotransferase analysis, Female, Humans, Immunohistochemistry, Male, Middle Aged, Polymerase Chain Reaction, Polyomavirus genetics, Carcinoma, Merkel Cell virology, DNA, Viral analysis, Merkel Cells virology, Polyomavirus isolation & purification, Retinoblastoma Protein analysis, Tumor Suppressor Protein p53 analysis
- Abstract
Merkel cell polyomavirus (MCPyV) was recently discovered in Merkel cell carcinoma (MCC), a clinically and pathologically heterogeneous malignancy of dermal neuroendocrine cells. To investigate this heterogeneity, we developed a tissue microarray (TMA) to characterize immunohistochemical staining of candidate tumor cell proteins and a quantitative PCR assay to detect MCPyV and measure viral loads. MCPyV was detected in 19 of 23 (74%) primary MCC tumors, but 8 of these had less than 1 viral copy per 300 cells. Viral abundance of 0.06-1.2 viral copies/cell was directly related to presence of retinoblastoma gene product (pRb) and terminal deoxyribonucleotidyl transferase (TdT) by immunohistochemical staining (p < or = 0.003). Higher viral abundance tumors tended to be associated with less p53 expression, younger age at diagnosis and longer survival (p < or = 0.08). These data suggest that MCC may arise through different oncogenic pathways, including ones independent of pRb and MCPyV.
- Published
- 2010
- Full Text
- View/download PDF
50. The AIDS and Cancer Specimen Resource: role in HIV/AIDS scientific discovery.
- Author
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Ayers LW, Silver S, McGrath MS, and Orenstein JM
- Abstract
The AIDS Cancer and Specimen Resource (ACSR) supports scientific discovery in the area of HIV/AIDS-associated malignancies. The ACSR was established as a cooperative agreement between the NCI (Office of the Director, Division of Cancer Treatment and Diagnosis) and regional consortia, University of California, San Francisco (West Coast), George Washington University (East Coast) and Ohio State University (Mid-Region) to collect, preserve and disperse HIV-related tissues and biologic fluids and controls along with clinical data to qualified investigators. The available biological samples with clinical data and the application process are described on the ACSR web site. The ACSR tissue bank has more than 100,000 human HIV positive specimens that represent different processing (43), specimen (15), and anatomical site (50) types. The ACSR provides special biospecimen collections and prepares speciality items, e.g., tissue microarrays (TMA), DNA libraries. Requests have been greatest for Kaposi's sarcoma (32%) and non-Hodgkin's lymphoma (26%). Dispersed requests include 83% tissue (frozen and paraffin embedded), 18% plasma/serum and 9% other. ACSR also provides tissue microarrays of, e.g., Kaposi's sarcoma and non-Hodgkin's lymphoma, for biomarker assays and has developed collaborations with other groups that provide access to additional AIDS-related malignancy specimens. ACSR members and associates have completed 63 podium and poster presentations. Investigators have submitted 125 letters of intent requests. Discoveries using ACSR have been reported in 61 scientific publications in notable journals with an average impact factor of 7. The ACSR promotes the scientific exploration of the relationship between HIV/AIDS and malignancy by participation at national and international scientific meetings, contact with investigators who have productive research in this area and identifying, collecting, preserving, enhancing, and dispersing HIV/AIDS-related malignancy specimens to funded, approved researchers at no fee. Scientific discovery has been advanced by this unique biorepository. Investigators are encouraged to browse the ACSR Internet site for materials to enhance their own scientific initiatives.
- Published
- 2007
- Full Text
- View/download PDF
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