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Lin SH, Wang Y, Hartley SW, Karyadi DM, Lee OW, Zhu B, Zhou W, Brown DW, Beilstein-Wedel E, Hazra R, Kacanek D, Chadwick EG, Marsit CJ, Poirier MC, Brummel SS, Chanock SJ, Engels EA, Machiela MJ. In-utero exposure to zidovudine-containing antiretroviral therapy and clonal hematopoiesis in HIV-exposed uninfected newborns. AIDS 2021; 35:1525-1535. [PMID: 33756513 PMCID: PMC8286286 DOI: 10.1097/qad.0000000000002894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Zidovudine (ZDV) has been extensively used in pregnant women to prevent vertical transmission of HIV but few studies have evaluated potential mutagenic effects of ZDV during fetal development. DESIGN Our study investigated clonal hematopoiesis in HIV-exposed uninfected (HEU) newborns, 94 of whom were ZDV-exposed and 91 antiretroviral therapy (ART)-unexposed and matched for potential confounding factors. METHODS Utilizing high depth sequencing and genotyping arrays, we comprehensively examined blood samples collected during the first week after birth for potential clonal hematopoiesis associated with fetal ZDV exposure, including clonal single nucleotide variants (SNVs), small insertions and deletions (indels), and large structural copy number or copy neutral alterations. RESULTS We observed no statistically significant difference in the number of SNVs and indels per person in ZDV-exposed children (adjusted ratio [95% confidence interval, CI] for expected number of mutations = 0.79 [0.50--1.22], P = 0.3), and no difference in the number of large structural alterations. Mutations in common clonal hematopoiesis driver genes were not found in the study population. Mutational signature analyses on SNVs detected no novel signatures unique to the ZDV-exposed children and the mutational profiles were similar between the two groups. CONCLUSION Our results suggest that clonal hematopoiesis at levels detectable in our study is not strongly influenced by in-utero ZDV exposure; however, additional follow-up studies are needed to further evaluate the safety and potential long-term impacts of in-utero ZDV exposure in HEU children as well as better investigate genomic aberrations occurring late in pregnancy.
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Affiliation(s)
- Shu-Hong Lin
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Youjin Wang
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Stephen W Hartley
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Danielle M Karyadi
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Olivia W Lee
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Bin Zhu
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Weiyin Zhou
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
- Cancer Genomics Research Laboratory, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Derek W Brown
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Erin Beilstein-Wedel
- Center for Biostatistics in AIDS Research, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Rohan Hazra
- Maternal and Pediatric Infectious Disease Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | - Deborah Kacanek
- Center for Biostatistics in AIDS Research, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Ellen G Chadwick
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Carmen J Marsit
- Departments of Environmental Health and Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Miriam C Poirier
- Carcinogen-DNA Interactions Section, Laboratory of Cancer Biology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Sean S Brummel
- Center for Biostatistics in AIDS Research, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Stephen J Chanock
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Eric A Engels
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
| | - Mitchell J Machiela
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville
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Liu Y, Park ES, Gibbons AT, Shide ED, Divi RL, Woodward RA, Poirier MC. Mitochondrial compromise in 3-year old patas monkeys exposed in utero to human-equivalent antiretroviral therapies. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2016; 57:526-34. [PMID: 27452341 PMCID: PMC4980240 DOI: 10.1002/em.22033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 06/21/2016] [Indexed: 05/25/2023]
Abstract
Antiretroviral (ARV) drug therapy, given during pregnancy for prevention of mother-to-child transmission of human immunodeficiency virus 1 (HIV-1), induces fetal mitochondrial dysfunction in some children. However, the persistence/reversibility of that dysfunction is unclear. Here we have followed Erythrocebus patas (patas) monkey offspring for up to 3 years of age (similar in development to a 15-year old human) after exposure of the dams to human-equivalent in utero ARV exposure protocols. Pregnant patas dams (3-5/exposure group) were given ARV drug combinations that included zidovudine (AZT)/lamivudine (3TC)/abacavir (ABC), or AZT/3TC/nevirapine (NVP), for the last 10 weeks (50%) of gestation. Infants kept for 1 and 3 years also received drug for the first 6 weeks of life. In offpsring at birth, 1 and 3 years of age mitochondrial morphology, examined by electron microscopy (EM), was compromised compared to the unexposed controls. Mitochondrial DNA (mtDNA), measured by hybrid capture chemiluminescence assay (HCCA) was depleted in hearts of patas exposed to AZT/3TC/NVP at all ages (P < 0.05), but not in those exposed to AZT/3TC/ABC at any age. Compared to unexposed controls, mitochondrial reserve capacity oxygen consumption rate (OCR by Seahorse) in cultured bone marrow mesenchymal fibroblasts from 3-year-old patas offspring was ∼50% reduced in AZT/3TC/ABC-exposed patas (P < 0.01), but not in AZT/3TC/NVP-exposed patas. Overall the data show that 3-year-old patas sustain persistent mitochondrial dysfunction as a result of perinatal ARV drug exposure. Environ. Mol. Mutagen. 57:526-534, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Yongmin Liu
- Carcinogen-DNA Interactions Section, Laboratory of Cancer Biology and Genetics, CCR, National Cancer Institute, NIH, Bethesda, MD
| | - Eunwoo Shim Park
- Carcinogen-DNA Interactions Section, Laboratory of Cancer Biology and Genetics, CCR, National Cancer Institute, NIH, Bethesda, MD
| | - Alexander T. Gibbons
- Carcinogen-DNA Interactions Section, Laboratory of Cancer Biology and Genetics, CCR, National Cancer Institute, NIH, Bethesda, MD
| | - Eric D. Shide
- Carcinogen-DNA Interactions Section, Laboratory of Cancer Biology and Genetics, CCR, National Cancer Institute, NIH, Bethesda, MD
| | - Rao L. Divi
- Methods and Technologies Branch, DCPC, National Cancer Institute, NIH, Bethesda, MD
| | | | - Miriam C. Poirier
- Carcinogen-DNA Interactions Section, Laboratory of Cancer Biology and Genetics, CCR, National Cancer Institute, NIH, Bethesda, MD
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3
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Snowdin JW, Hsiung CH, Kesterson DG, Kamath VG, McKee EE. Effects of Zidovudine Treatment on Heart mRNA Expression and Mitochondrial DNA Copy Number Associated with Alterations in Deoxynucleoside Triphosphate Composition in a Neonatal Rat Model. Antimicrob Agents Chemother 2015; 59:6328-36. [PMID: 26248377 PMCID: PMC4576025 DOI: 10.1128/aac.01180-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 07/21/2015] [Indexed: 01/22/2023] Open
Abstract
The prevention of mother-to-child transmission (MTCT) of HIV is a crucial component in HIV therapy. Nucleoside reverse transcriptase inhibitors (NRTIs), primarily 3'-azido-3'-thymidine (AZT [zidovudine]), have been used to treat both mothers and neonates. While AZT is being replaced with less toxic drugs in treating mothers in MTCT prevention, it is still commonly used to treat neonates. Problems related to mitochondrial toxicity and potential mutagenesis associated with AZT treatment have been reported in treated cohorts. Yet little is known concerning the metabolism and potential toxicity of AZT on embryonic and neonatal tissues, especially considering that the enzymes of nucleoside metabolism change dramatically as many tissues convert from hyperplastic to hypertrophic growth during this period. AZT is known to inhibit thymidine phosphorylation and potentially alter deoxynucleoside triphosphate (dNTP) pools in adults. This study examines the effects of AZT on dNTP pools, mRNA expression of deoxynucleoside/deoxynucleotide metabolic enzymes, and mitochondrial DNA levels in a neonatal rat model. Results show that AZT treatment dramatically altered dNTP pools in the first 7 days of life after birth, which normalized to age-matched controls in the second and third weeks. Additionally, AZT treatment dramatically increased the mRNA levels of many enzymes involved in deoxynucleotide synthesis and mitochondrial biogenesis during the first week of life, which normalized to age-matched controls by the third week. These results were correlated with depletion of mitochondrial DNA noted in the second week. Taken together, results demonstrated that AZT treatment has a powerful effect on the deoxynucleotide synthesis pathways that may be associated with toxicity and mutagenesis.
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Affiliation(s)
- Jacob W Snowdin
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, Michigan, USA
| | - Chia-Heng Hsiung
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, Michigan, USA
| | - Daniel G Kesterson
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, Michigan, USA
| | - Vasudeva G Kamath
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, Michigan, USA
| | - Edward E McKee
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, Michigan, USA
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4
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Demir M, Laywell ED. Neurotoxic effects of AZT on developing and adult neurogenesis. Front Neurosci 2015; 9:93. [PMID: 25852464 PMCID: PMC4367529 DOI: 10.3389/fnins.2015.00093] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 03/05/2015] [Indexed: 11/18/2022] Open
Abstract
Azidothymidine (AZT) is a synthetic, chain-terminating nucleoside analog used to treat HIV-1 infection. While AZT is not actively transported across the blood brain barrier, it does accumulate at high levels in cerebrospinal fluid, and subsequently diffuses into the overlying parenchyma. Due to the close anatomical proximity of the neurogenic niches to the ventricular system, we hypothesize that diffusion from CSF exposes neural stem/progenitor cells and their progeny to biologically relevant levels of AZT sufficient to perturb normal cell functions. We employed in vitro and in vivo models of mouse neurogenesis in order to assess the effects of AZT on developing and adult neurogenesis. Using in vitro assays we show that AZT reduces the population expansion potential of neural stem/progenitor cells by inducing senescence. Additionally, in a model of in vitro neurogenesis AZT severely attenuates neuroblast production. These effects are mirrored in vivo by clinically-relevant animal models. We show that in utero AZT exposure perturbs both population expansion and neurogenesis among neural stem/progenitor cells. Additionally, a short-term AZT regimen in adult mice suppresses subependymal zone neurogenesis. These data reveal novel negative effects of AZT on neural stem cell biology. Given that the sequelae of HIV infection often include neurologic deficits—subsumed under AIDS Dementia Complex (Brew, 1999)—it is important to determine to what extent AZT negatively affects neurological function in ways that contribute to, or exacerbate, ADC in order to avoid attributing iatrogenic drug effects to the underlying disease process, and thereby skewing the risk/benefit analysis of AZT therapy.
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Affiliation(s)
- Meryem Demir
- Department of Anatomy and Cell Biology, College of Medicine, University of Florida Gainesville, FL, USA
| | - Eric D Laywell
- Department of Biomedical Sciences, College of Medicine, Florida State University Tallahassee, FL, USA
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5
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Pediatric Human Immunodeficiency Virus infection and cancer in the Highly Active Antiretroviral Treatment (HAART) era. Cancer Lett 2014; 347:38-45. [DOI: 10.1016/j.canlet.2014.02.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/13/2014] [Accepted: 02/03/2014] [Indexed: 12/18/2022]
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6
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Olivero OA, Torres LR, Gorjifard S, Momot D, Marrogi E, Divi RL, Liu Y, Woodward RA, Sowers MJ, Poirier MC. Perinatal exposure of patas monkeys to antiretroviral nucleoside reverse-transcriptase inhibitors induces genotoxicity persistent for up to 3 years of age. J Infect Dis 2013; 208:244-8. [PMID: 23559463 DOI: 10.1093/infdis/jit146] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Erythrocebus patas (patas) monkeys were used to model antiretroviral (ARV) drug in human immunodeficiency virus type 1-infected pregnant women. METHODS Pregnant patas dams were given human-equivalent doses of ARVs daily during 50% of gestation. Mesenchymal cells, cultured from bone marrow of patas offspring obtained at birth and at 1 and 3 years of age, were examined for genotoxicity, including centrosomal amplification, micronuclei, and micronuclei containing whole chromosomes. RESULTS Compared with controls, statistically significant increases (P < .05) in centrosomal amplification, micronuclei, and micronuclei containing whole chromosomes were found in mesenchymal cells from most groups of offspring at the 3 time points. CONCLUSIONS Transplacental nucleoside reverse-transcriptase inhibitor exposures induced fetal genotoxicity that was persistent for 3 years.
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Affiliation(s)
- Ofelia A Olivero
- Carcinogen-DNA Interactions Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD 20892-4255, USA
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7
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Comparative analysis of genetic toxicity of antiretroviral combinations in somatic cells of Drosophila melanogaster. Food Chem Toxicol 2013; 53:299-309. [DOI: 10.1016/j.fct.2012.12.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 11/19/2012] [Accepted: 12/04/2012] [Indexed: 12/11/2022]
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8
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Campos PB, Sartore RC, Ramalho BL, Costa ES, Rehen SK. Cycle arrest and aneuploidy induced by zidovudine in murine embryonic stem cells. Mutagenesis 2012; 27:431-6. [DOI: 10.1093/mutage/ger093] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
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9
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Krishnan S, Schouten JT, Jacobson DL, Benson CA, Collier AC, Koletar SL, Santana J, Sattler FR, Mitsuyasu R. Incidence of non-AIDS-defining cancer in antiretroviral treatment-naïve subjects after antiretroviral treatment initiation: an ACTG longitudinal linked randomized trials analysis. Oncology 2011; 80:42-9. [PMID: 21606663 PMCID: PMC3121543 DOI: 10.1159/000328032] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 01/24/2011] [Indexed: 01/16/2023]
Abstract
BACKGROUND Prospective data on factors associated with the non-AIDS-defining cancer (NADC) incidence in HIV-infected individuals are limited. METHODS We examined the NADC incidence in 3,158 antiretroviral treatment (ART)-naïve subjects after ART initiation in AIDS Clinical Trials Group trials; extended follow-up was available for 2,122 subjects. Poisson regression was used to examine the associations between covariates and incident NADC. RESULTS At ART initiation, subjects (median age 37 years) were 40% non-Hispanic whites, and 82% were male; 23% had CD4+ T cell count ≤ 50 cells/mm³ and 25% had CD4 >350 cells/mm³. Median follow-up was 3.8 years. Among 64 incident NADCs, the most common were 8 anal cancers, 8 basal cell carcinomas, 8 Hodgkin's disease, and 6 lung cancers. In univariate models, age, smoking and recent (time-updated) CD4 were associated with incident NADC. There was no association between initial ART drug class (protease inhibitor, nucleoside reverse transcriptase inhibitor and nonnucleoside reverse transcriptase inhibitor) and NADC. After adjusting for age, race and sex: smoking [relative risk = 2.12 (95% CI = 1.1-4.08)] and recent CD4 (≤ 50 cells/mm³: 3.58, 1.22-10.45; 51-200 cells/mm³: 2.54, 1.30-5.0; 201-350 cells/mm³: 2.37, 1.32-4.26 vs. >350 cells/mm³) were associated with NADC. CONCLUSION Smoking and lower recent CD4 levels, but not initial ART drug class, were associated with NADC. Strategies for maintaining higher CD4 cell counts and successful smoking cessation may reduce the NADC incidence in the HIV-infected population.
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Affiliation(s)
- Supriya Krishnan
- Center for Biostatistics in AIDS Research, Harvard School of Public Health, Boston, Mass., USA
| | - Jeffrey T. Schouten
- Department of Surgery, University of Washington School of Medicine, Seattle, Wash., USA
| | - Denise L. Jacobson
- Center for Biostatistics in AIDS Research, Harvard School of Public Health, Boston, Mass., USA
| | - Constance A. Benson
- Division of Infectious Diseases, University of California, San Diego, Calif., USA
| | - Ann C. Collier
- University of Washington School of Medicine and Harborview Medical Center, Seattle, Wash., USA
| | - Susan L. Koletar
- Division of Infectious Diseases, Ohio State University, Columbus, Ohio, USA
| | - Jorge Santana
- University of Puerto Rico, School of Medicine, Puerto Rico, P.R., USA
| | | | - Ronald Mitsuyasu
- Center for Clinical AIDS Research and Education, University of California, Los Angeles, Calif., USA
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10
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Wu Q, Beland FA, Chang CW, Fang JL. XPC is essential for nucleotide excision repair of zidovudine-induced DNA damage in human hepatoma cells. Toxicol Appl Pharmacol 2010; 251:155-62. [PMID: 21192964 DOI: 10.1016/j.taap.2010.12.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 12/14/2010] [Accepted: 12/16/2010] [Indexed: 12/18/2022]
Abstract
Zidovudine (3'-azido-3'-dexoythymidine, AZT), a nucleoside reverse transcriptase inhibitor, can be incorporated into DNA and cause DNA damage. The mechanisms underlying the repair of AZT-induced DNA damage are unknown. To investigate the pathways involved in the recognition and repair of AZT-induced DNA damage, human hepatoma HepG2 cells were incubated with AZT for 2 weeks and the expression of DNA damage signaling pathways was determined using a pathway-based real-time PCR array. Compared to control cultures, damaged DNA binding and nucleotide excision repair (NER) pathways showed significantly increased gene expression. Further analysis indicated that AZT treatment increased the expression of genes associated with NER, including XPC, XPA, RPA1, GTF2H1, and ERCC1. Western blot analysis demonstrated that the protein levels of XPC and GTF2H1 were also significantly up-regulated. To explore further the function of XPC in the repair of AZT-induced DNA damage, XPC expression was stably knocked down by 71% using short hairpin RNA interference. In the XPC knocked-down cells, 100 μM AZT treatment significantly increased [³H]AZT incorporation into DNA, decreased the total number of viable cells, increased the release of lactate dehydrogenase, induced apoptosis, and caused a more extensive G2/M cell cycle arrest when compared to non-transfected HepG2 cells or HepG2 cells transfected with a scrambled short hairpin RNA sequence. Overall, these data indicate that XPC plays an essential role in the NER repair of AZT-induced DNA damage.
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Affiliation(s)
- Qiangen Wu
- Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079, USA
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11
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Inhibition of NF-κB activation sensitizes U937 cells to 3'-azido-3'-deoxythymidine induced apoptosis. Cell Death Dis 2010; 1:e81. [PMID: 21368854 PMCID: PMC3035897 DOI: 10.1038/cddis.2010.58] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In this study, we investigated molecular mechanisms underlying low susceptibility to apoptosis induced by the nucleoside analog azidothymidine (AZT) and the role of nuclear factor-κB (NF-κB) activation in these phenomena. A preliminary screening in different cell lines indicated U937 monocytic cell line as suitable to this purpose. Treatment of U937 cells even with suprapharmacological concentrations of AZT induced only moderate levels of apoptosis. Surprisingly, SuperArray analysis showed that AZT induced the transcriptional activity of both pro- and anti-apoptotic genes. Interestingly, moreover, several genes upregulated by AZT were NF-κB related. In fact, AZT, after an initial inhibition of NF-κB activation with respect to control, induced a transient, but consistent, increase in NF-κB-binding activity. Inhibition of NF-κB activation in U937 cells, stably transfected with a dominant-negative IκBα or by pharmacological treatment, sensitized them to apoptosis induced by AZT and impaired the upregulation of anti-apoptotic genes in response to AZT treatment, with respect to control cells. These results indicate that NF-κB activation by AZT has a role in protecting target cells from apoptotic cell death, improving our understanding of the toxicology and the therapeutic usage of this drug.
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12
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Walker DM, Kajon AE, Torres SM, Carter MM, McCash CL, Swenberg JA, Upton PB, Hardy AW, Olivero OA, Shearer GM, Poirier MC, Walker VE. WR1065 mitigates AZT-ddI-induced mutagenesis and inhibits viral replication. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2009; 50:460-72. [PMID: 19334055 PMCID: PMC3197270 DOI: 10.1002/em.20482] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The success of nucleoside reverse transcriptase inhibitors (NRTIs) in treating HIV-1 infection and reducing mother-to-child transmission of the virus during pregnancy is accompanied by evidence that NRTIs cause long-term health risks for cancer and mitochondrial disease. Thus, agents that mitigate toxicities of the current combination drug therapies are needed. Previous work had shown that the NRTI-drug pair zidovudine (AZT)-didanosine (ddI) was highly cytotoxic and mutagenic; thus, we conducted preliminary studies to investigate the ability of the active moiety of amifostine, WR1065, to protect against the deleterious effects of this NRTI-drug pair. In TK6 cells exposed to 100 muM AZT-ddI (equimolar) for 3 days with or without 150 muM WR1065, WR1065 enhanced long-term cell survival and significantly reduced AZT-ddI-induced mutations. Follow-up studies were conducted to determine if coexposure to AZT and WR1065 abrogated the antiretroviral efficacy of AZT. In human T-cell blasts infected with HIV-1 in culture, inhibition of p24 protein production was observed in cells treated with 10 muM AZT in the absence or presence of 5-1,000 muM WR1065. Surprisingly, WR1065 alone exhibited dose-related inhibition of HIV-1 p24 protein production. WR1065 also had antiviral efficacy against three species of adenovirus and influenza A and B. Intracellular levels of unbound WR1065 were measured following in vitro/in vivo drug exposure. These pilot study results indicate that WR1065, at low intracellular levels, has cytoprotective and antimutagenic activities against the most mutagenic pair of NRTIs and has broad spectrum antiviral effects. These findings suggest that the activities have a possible common mode of action that merits further investigation.
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Affiliation(s)
- Dale M. Walker
- BioMosaics, Inc., Burlington, Vermont
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Adriana E. Kajon
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Salina M. Torres
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
- College of Pharmacy, University of New Mexico, Albuquerque, New Mexico
| | - Meghan M. Carter
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | | | - James A. Swenberg
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Patricia B. Upton
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Andrew W. Hardy
- AMRV, CCR, National Cancer Institute, NIH, Bethesda, Maryland
| | - Ofelia A. Olivero
- CDI Section, LCBG, CCR, National Cancer Institute, NIH, Bethesda, Maryland
| | - Gene M. Shearer
- AMRV, CCR, National Cancer Institute, NIH, Bethesda, Maryland
| | - Miriam C. Poirier
- CDI Section, LCBG, CCR, National Cancer Institute, NIH, Bethesda, Maryland
| | - Vernon E. Walker
- BioMosaics, Inc., Burlington, Vermont
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
- College of Pharmacy, University of New Mexico, Albuquerque, New Mexico
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13
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Bliss-Holtz J. Defunct gadgets and changing times. ISSUES IN COMPREHENSIVE PEDIATRIC NURSING 2009; 32:1-3. [PMID: 19263289 DOI: 10.1080/01460860802637692] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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14
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Torres SM, Walker DM, McCash CL, Carter MM, Ming J, Cordova EM, Pons RM, Cook DL, Seilkop SK, Copeland WC, Walker VE. Mutational analysis of the mitochondrial tRNA genes and flanking regions in umbilical cord tissue from uninfected infants receiving AZT-based therapies for prophylaxis of HIV-1. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2009; 50:10-26. [PMID: 19031409 PMCID: PMC3191876 DOI: 10.1002/em.20433] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A sensitive vertical denaturing gradient gel electrophoresis (DGGE) method, using 13 unipolar psoralen-clamped PCR primer pairs, was developed for detecting sequence variants in the 22 tRNA genes and flanking regions (together spanning approximately 21%) of the human mitochondrial genome. A study was conducted to determine (i) if mitochondrial DNA (mtDNA) polymorphisms and/or mutations were detectable in healthy newborns and (ii) if prepartum 3'-azido-2',3'-dideoxythymidine (AZT) based HIV-1 prophylaxis was associated with significant increases in mtDNA mutations and changes in the degree of heteroplasmy of sequence variants in uninfected infants born to HIV-1-infected mothers. DGGE analysis of umbilical cord tissue (where vascular endothelium and smooth muscle cells are the major source of mtDNA) showed that mtDNA sequence variants were significantly elevated by threefold in AZT-treated infants compared with unexposed controls (P < 0.001), with 24 changes observed in 19/52 (37%) treated newborns (averaging 0.46 changes/subject) versus only eight changes found in 7/55 (13%) unexposed newborns (averaging 0.15 changes/subject). Six distinct sequence variants occurring in unexposed controls were predominately synonymous and homoplasmic, representing previously reported polymorphisms. Uninfected infants exposed to a combination of AZT and 2',3'-dideoxy-3'-thiacytidine and "maternal HIV-1" had a significant shift in the spectrum of mutations (P = 0.04) driven by increases in nonsynonymous heteroplasmic sequence variants at polymorphic sites (10 distinct variants) and novel sites (four distinct variants). While the weight of evidence suggests that prepartum AZT-based prophylaxis produces mtDNA mutations, additional research is needed to determine the degree to which fetal responses to maternal HIV-1 infection, in the absence of antiretroviral treatment, contribute to prenatal mtDNA mutagenesis.
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Affiliation(s)
- Salina M. Torres
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Dale M. Walker
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
- BioMosaics, Inc., Burlington, Vermont
| | | | - Meghan M. Carter
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Jessica Ming
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | | | - Rachel M. Pons
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Dennis L. Cook
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | | | - William C. Copeland
- Laboratory of Molecular Genetics, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina
| | - Vernon E. Walker
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico
- BioMosaics, Inc., Burlington, Vermont
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15
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Matteucci C, Minutolo A, Balestrieri E, Ascolani A, Grelli S, Macchi B, Mastino A. Effector caspase activation, in the absence of a conspicuous apoptosis induction, in mononuclear cells treated with azidothymidine. Pharmacol Res 2008; 59:125-33. [PMID: 19073261 DOI: 10.1016/j.phrs.2008.11.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 11/06/2008] [Accepted: 11/19/2008] [Indexed: 12/12/2022]
Abstract
In the present study we focused our attention on the effect of AZT, at pharmacological and suprapharmacological concentrations, on some apoptosis-related key events and, particularly, on caspase activation in fresh human peripheral blood mononuclear cells (PBMCs). The main results can be summarized as follows: (i) AZT induced a strong, dose-dependent antiproliferative effect in mitogen-stimulated PBMCs, but low levels of cytotoxicity. in comparison with 5FU; (ii) low levels of cytotoxicity were coupled with a poor increase of apoptosis after AZT treatment in PBMCs; (iii) despite low levels of apoptosis, remarkable signs of both initiator and effector caspase enhanced expression with respect to control were detected by immunoblot analysis in AZT-treated PBMCs; (iv) enhanced caspase expression was associated with an increased expression of both anti-apoptotic Bcl-2 and pro-apoptotic Fas and p53 proteins, as detected by flow cytometry analysis; (v) combination treatment in vitro with AZT and anti-Fas significantly increased apoptosis in PBMCs with respect to single treatments. Overall, these results suggest that AZT treatment activates a complex, and apparently contrasting apoptosis-related signaling activity in PBMCs and that additional events are necessary to disrupt the balance induced by AZT towards apoptosis, on these cells.
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Affiliation(s)
- Claudia Matteucci
- Department of Experimental Medicine and Biochemical Sciences, University of Rome "Tor Vergata", Rome, Italy
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16
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Vikram A, Tripathi D, Pawar A, Ramarao P, Jena G. Pre-bled-young-rats in genotoxicity testing: A model for peripheral blood micronucleus assay. Regul Toxicol Pharmacol 2008; 52:147-57. [DOI: 10.1016/j.yrtph.2008.07.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2008] [Revised: 07/09/2008] [Accepted: 07/23/2008] [Indexed: 11/25/2022]
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Incidence of cancer in children perinatally exposed to nucleoside reverse transcriptase inhibitors. AIDS 2008; 22:2165-77. [PMID: 18832880 DOI: 10.1097/qad.0b013e328311d18b] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
CONTEXT Long-term studies of tolerance to perinatal exposure to antiretroviral nucleoside reverse transcriptase inhibitors are required, in view of the potential genotoxicity of some of these molecules. OBJECTIVE To evaluate the incidence of cancers in uninfected children born to HIV-infected mothers. METHOD Cancers were detected in a nationwide prospective cohort of children born to HIV-infected mothers by standardized questionnaire during the prospective follow-up period of 2 years; thereafter, they were detected by spontaneous pharmacovigilance declaration and by crosschecking data with the national registries of childhood cancer. Standardized incidence ratio for incidence comparisons with general population. RESULTS Ten cases of cancer were detected among the 9127 exposed HIV-uninfected children (median age: 5.4 years, 53 052 person-years of follow-up). The overall incidence did not differ significantly from that expected for the general population: 10 cases observed versus 8.9 and 9.6 expected depending on whether 1990-1999 or 2000-2004 national rates were used as reference [standardized incidence ratio of 1.1 (0.3-1.5) and 1.0 (0.5-1.9)]. Five cases of central nervous system cancer were observed (standardized incidence ratio of 3.1 [1.0-7.2] P = 0.05 and 2.4 [0.8-5.6], P = 0.12). The relative risk of cancer for children exposed to didanosine-lamivudine combination was higher than that for zidovudine monotherapy [hazard ratio: 13.6 (2.5-73.9)]. CONCLUSION This study did not evidence an overall increase in cancer risk in nucleoside reverse transcriptase inhibitor exposed children until 5 years of age. Results suggesting associations with specific nucleoside reverse transcriptase inhibitor combinations need further investigations. A longer surveillance, including differential analysis of the different cancer sites and various nucleoside reverse transcriptase inhibitors administered is warranted.
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18
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Tripathi DN, Pawar AA, Vikram A, Ramarao P, Jena GB. Use of the alkaline comet assay for the detection of transplacental genotoxins in newborn mice. Mutat Res 2008; 653:134-9. [PMID: 18468946 DOI: 10.1016/j.mrgentox.2008.03.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2007] [Revised: 02/28/2008] [Accepted: 03/12/2008] [Indexed: 11/30/2022]
Abstract
Several lines of evidence show that in utero exposure to different toxicants has greater consequences than their exposure during adult life. This may be due to involvement of critical developmental stages, physiological immaturity and the long later-life span over which disease may initiate, develop and progress. The in vivo alkaline comet (single-cell gel electrophoresis) assay has been favoured by the scientific community for the evaluation of genotoxins. The objective of this study was to demonstrate the suitability of alkaline comet assay in detecting transplacental genotoxins using newborn mice. Here, we report the successful use of the comet assay in detecting multi-organ genotoxicity of known transplacental genotoxins in newborn mice. Three well known transplacental genotoxic agents, cyclophosphamide (CP), mitomycin-C (MMC) and zidovudine (AZT) were tested in pregnant Swiss mice. These compounds were administered in the late gestational period (16-20th days of pregnancy) and the comet assay was performed with lymphocytes, bone marrow, liver and kidney cells of newborn mice. Significant DNA damage was observed in all the tissues with tested transplacental genotoxins. The results of the comet assay were confirmed by the micronucleus (MN) assay of the peripheral blood of newborn mice. The results of this study provide sufficient evidence that the comet assay can be applied successfully for the detection of transplacental genotoxins in newborn mice.
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Affiliation(s)
- D N Tripathi
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Sector-67, S.A.S. Nagar, Mohali, Punjab 160062, India
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Castro DJ, Baird WM, Pereira CB, Giovanini J, Löhr CV, Fischer KA, Yu Z, Gonzalez FJ, Krueger SK, Williams DE. Fetal mouse Cyp1b1 and transplacental carcinogenesis from maternal exposure to dibenzo(a,l)pyrene. Cancer Prev Res (Phila) 2008; 1:128-34. [PMID: 19138945 DOI: 10.1158/1940-6207.capr-07-0004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Dibenzo(a,l)pyrene (DBP) is among the most potent carcinogenic polycyclic aromatic hydrocarbons. Previously, we showed that DBP administration to pregnant mice resulted in high mortality of offspring from an aggressive T-cell lymphoma. All mice that survive to 10 months of age exhibit lung tumors with high multiplicity. Recombinant cytochrome P450 (cyp) 1b1 from mice and the homologue 1B1 in humans exhibit high activity toward the metabolic activation of DBP. Targeted disruption of the cyp1b1 gene protects against most DBP-dependent cancers. Mice heterozygous for the disrupted cyp1b1 allele were used to examine the effect of cyp1b1 gene dosage on DBP transplacental carcinogenesis. Dams were treated with 1 or 15 mg/kg of DBP or 50 mg/kg of benzo(a)pyrene. Cyp1b1-null offspring did not develop lymphoma, whereas wild-type and heterozygous siblings, born to dams given the high dose of DBP, exhibited significant mortalities between 10 and 30 weeks of age. At 10 months, all groups had lung adenomas or carcinomas [9.5%, 40.3%, 25.6%, and 100% incidences for controls, benzo(a)pyrene, 1 and 15 mg/kg DBP, respectively]. Cyp1b1 status did not alter benzo(a)pyrene-dependent carcinogenesis. At 1 mg/kg DBP, cyp1b1 status altered the incidence of lung tumors (19.0, 27.8, and 28.6% for nulls, heterozygous, and wild-type, respectively). At 15 mg/kg, tumor multiplicities in cyp1b1 wild-type (9.3) and heterozygous (9.5) offspring were nearly twice that of cyp1b1-null siblings (5.0). These data confirm that cyp1b1 bioactivation of DBP occurs in fetal target tissues, following transplacental exposure, with the thymus and lung as primary and secondary targets, respectively.
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Affiliation(s)
- David J Castro
- Department of Environmental and Molecular Toxicology, Oregon State University, ALS 1007, Corvallis, OR 97331-7301, USA
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Relevance of experimental models for investigation of genotoxicity induced by antiretroviral therapy during human pregnancy. Mutat Res 2008; 658:184-90. [PMID: 18295533 DOI: 10.1016/j.mrrev.2007.12.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 12/12/2007] [Accepted: 12/13/2007] [Indexed: 11/21/2022]
Abstract
The current incidence of human immunodeficiency virus (HIV-1)/AIDS affects around 7000 pregnant women in the United States. When given during pregnancy, the nucleoside analog 3'-azido-3'-deoxythymidine (AZT) significantly reduces maternal-fetal transmission. It has been previously shown that AZT is incorporated into DNA, where it causes mutations in the HPRT and TK genes. It also changes cell cycle gene expression, and induces S-phase arrest, micronuclei, chromosomal aberrations, sister chromatid exchanges, telomeric attrition, and other genotoxic effects in cultured cells. A predicted consequence of these events is genomic instability that together, with clastogenicity may contribute to the carcinogenic potency of AZT. Various aspects of genotoxicity are explored in this contribution seeking to understand the multiple effects of this antiretroviral agent in animal models and humans. This mini-review describes some of the experimental models used to elucidate the genotoxicity induced by antiretroviral therapy during human pregnancy. The use of diverse methods to detect biomarkers of exposure, such as an AZT-specific radioimmunoassay, micronuclei bearing intact chromosomes, and telomeric DNA attrition highlight the role of in vitro models to elucidate exposure and risk. The relevance of the in vitro models is followed by the introduction of the role of the nucleoside analogs in transplacental carcinogenesis along with the description of a transplacental perfusion model and a transplacental carcinogenesis rodent model. In a more direct clinical application the use of AZT-DNA incorporation as a biomarker of exposure, in experiments conducted in vivo in Erythrocebus patas monkeys and in humans, addresses the possibility of elucidation of potential cancer risk in those infants exposed in utero. Two relevant aspects of this contribution are the potential application of some of the models described in this mini-review, as diagnostic tools in antiretroviral-exposed populations, and the use of these models to understand the nature of the genotoxicities and minimize the undesirable side effects of the antiretroviral therapy.
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Olivero OA, Ming JM, Das S, Vazquez IL, Richardson DL, Weston A, Poirier MC. Human inter-individual variability in metabolism and genotoxic response to zidovudine. Toxicol Appl Pharmacol 2007; 228:158-64. [PMID: 18206198 DOI: 10.1016/j.taap.2007.12.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Revised: 11/16/2007] [Accepted: 12/06/2007] [Indexed: 11/16/2022]
Abstract
A mainstay of the antiretroviral drugs used for therapy of HIV-1, zidovudine (AZT) is genotoxic and becomes incorporated into DNA. Here we explored host inter-individual variability in AZT-DNA incorporation, by AZT radioimmunoassay (RIA), using 19 different strains of normal human mammary epithelial cells (NHMECs) exposed for 24 h to 200 microM AZT. Twelve of the 19 NHMEC strains showed detectable AZT-DNA incorporation levels (16 to 259 molecules of AZT/10(6) nucleotides), while 7 NHMEC strains did not show detectable AZT-DNA incorporation. In order to explore the basis for this variability, we compared the 2 NHMEC strains that showed the highest levels of AZT-DNA incorporation (H1 and H2) with 2 strains showing no detectable AZT-DNA incorporation (L1 and L2). All 4 strains had similar (> or =80%) cell survival, low levels of accumulation of cells in S-phase, and no relevant differences in response to the direct-acting mutagen bleomycin (BLM). Finally, when levels of thymidine kinase 1 (TK1), the first enzyme in the pathway for incorporation of AZT into DNA, were determined by Western blot analysis in all 19 NHMEC strains at 24 h of AZT exposure, higher TK1 protein levels were found in the 12 strains showing AZT-DNA incorporation, compared to the 7 showing no incorporation (p=0.0005, Mann-Whitney test). Furthermore, strains L1 and L2, which did not show AZT-DNA incorporation at 24 h, did have measurable incorporation by 48 and 72 h. These data suggest that variability in AZT-DNA incorporation may be modulated by inter-individual differences in the rate of induction of TK1 in response to AZT exposure.
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Affiliation(s)
- Ofelia A Olivero
- Carcinogen-DNA Interactions Section, Laboratory of Cancer Biology and Genetics, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Bethesda, MD 20892-4255, USA.
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