Mutagenesis of Single/Combined NRTI Drugs in Human Cells

人类细胞中单一/组合 NRTI 药物的诱变

• 批准号: 6465902
• 负责人: VERNON E WALKER
• 金额: $ 37.84万
• 依托单位: LOVELACE BIOMEDICAL & ENVIRONMENTAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-04-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6465902
• 关键词: AIDS therapy; DNA damage; HIV infections; antiviral agents; cancer risk; carcinogens; cord blood; drug adverse effect; gene mutation; genetic susceptibility; lamivudine; lymphoblast; mutagens; nucleoside analog; phenotype; placental transfer; polymerase chain reaction; radioimmunoassay; reverse transcriptase inhibitors; stavudine; tissue /cell culture; zidovudine

DESCRIPTION (provided by applicant): Highly active antiretroviral therapy (HAART) has been effective at reducing the transmission of HIV from mother to infant, but the combinations of drugs used for HAART in pregnant women poses a risk for neoplasia in the infants exposed in utero to nucleoside analogue reverse transcriptase inhibitors (NRTIs). The purpose of this proposal is to determine the extent of nuclear DNA damage induced by exposure to specific NRTI's, alone or in combination, in human lymphoblastoid cells (AZH-1), and to determine the variability in the mutation susceptibility phenotype in human cord blood lymphocytes. Experiments will be performed to measure (by specific RIAs) DNA incorporation of zidovudine (AZT), lamivudine (3TC), and/or stavudine (d4T), and to measure and characterize the mutagenic response at the HPRT and APRT loci of AZH-1cells and the HPRT locus of cord blood cells (using cell cloning assays) exposed in culture to clinically important antiretroviral drugs, as single agents or combinations. This work is an extension of studies previously conducted by our group to investigate the in utero mutagenicity of perinatal exposure of infants to AZT. It was demonstrated that a direct correlation exists between the level of the AZT incorporated into DNA and the levels of mutations induced at specific loci in human cells. Second, co-exposure to AZT and a second NRTI (ddI) potentiates AZT-DNA incorporation and mutation induction in vitro. Third, NRTI therapy using AZT alone or with 3TC induces significant genotoxic and mutagenic effects in infants exposed in utero, and the increases in mutagenic responses persist for at least one year after birth. Data indicate that this increase is driven by a subset of the children, suggesting that individual susceptibility factors may influence the levels of DNA damage and mutation that results from in utero prophylaxis. AZT is also a transplacental carcinogen in exposed mice and rats. The proposed work will identify the drugs/drug combinations with the lowest mutagenic potential, will initiate studies to define the basis for the increased susceptibility to mutagenesis in a subset of AZT-3TC exposed infants, and will form the foundation for quantitative risk assessments of perinatal prophylaxis using individual NRTIs or combinations of NRTIs.

描述（由申请人提供）：高度活跃的抗逆转录病毒疗法 （Haart）一直有效地减少艾滋病毒从母亲到 婴儿，但在孕妇中用于Haart的药物的组合构成了 在子宫内暴露于核苷类似物的婴儿中肿瘤的风险 逆转录酶抑制剂（NRTIS）。该提议的目的是 确定暴露于特定的核DNA损伤的程度 在人类淋巴母细胞（AZH-1）中，单独或组合NRTI，并 确定人类突变敏感性表型的变异性 脐带血淋巴细胞。将进行实验以测量（通过特定 RIAS）ZIDOVUDINE（AZT），LAMIVUDINE（3TC）和/或Stavudine的DNA掺入 （D4T），并在HPRT和 AZH-1细胞的APRT基因座和脐带血细胞的HPRT基因座（使用细胞 克隆测定）在培养物中暴露于临床上重要的抗逆转录病毒 药物，作为单一药物或组合。这项工作是研究的扩展 以前由我们小组进行了研究的子宫内诱变性 婴儿围产期暴露于AZT。已经证明了直接 相关性存在于DNA中的AZT水平和 在人类细胞中特定基因座诱导的突变水平。第二， 对AZT和第二个NRTI（DDI）的共同曝光增强了AZT-DNA掺入 和体外突变诱导。第三，单独使用AZT或与NRTI治疗 3TC诱导暴露于婴儿的婴儿的遗传毒性和诱变作用明显 子宫，诱变反应的增加持续至少一年 出生后。数据表明，这种增加是由一个子集驱动的 儿童，表明个人的敏感性因素可能会影响 由子宫预防导致的DNA损伤和突变水平。 AZT 也是暴露的小鼠和大鼠中的移植致癌物。拟议的工作 将识别具有最低诱变潜力的药物/药物组合， 将启动研究以定义提高易感性的基础 AZT-3TC暴露婴儿的一部分中的诱变，将形成 使用围产期预防的定量风险评估基础 单个NRTI或NRTI的组合。