Biochemical Strategies to Increase Leukemia Response

提高白血病反应的生化策略

• 批准号: 6948173
• 负责人: VARSHA GANDHI
• 金额: $ 26.43万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-15 至 2007-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6948173
• 关键词: CD95 molecule; DNA replication; acute myelogenous leukemia; adenosine triphosphate; antileukemic agent; apoptosis; cell cycle; clinical research; combination cancer therapy; cytochrome c; cytotoxicity; drug interactions; drug metabolism; drug screening /evaluation; flow cytometry; human subject; human therapy evaluation; membrane potentials; mitochondrial membrane; neoplastic cell; nucleoside analog; oxidative phosphorylation; pharmacokinetics; polymerase chain reaction; ribonucleotide reductase

DESCRIPTION (provided by applicant): This proposal is an extension of CA57629 that has been focused on understanding the metabolism, mechanism of action, and interaction of nucleoside analogs. With the success rate of analogs in leukemias, several laboratories including ours have investigated the mechanisms of cell death by these agents. The steps include formation of triphosphate of the analog, incorporation into replicating DNA, inhibition of ribonucleotide reductase (with newer analogs) and finally inhibition of DNA synthesis. Continued inhibition of DNA synthesis proceeds to cell death through apoptosis. When tested in cell lines, which are actively cycling and replicating DNA, such scenario seems to be in place. However, when one tries to validate this process during therapy, the outcome is conflicting and intriguing. The biology of leukemia cells in the body is very different from cell lines in culture. Leukemia cells in peripheral blood are generally non- or slow- cycling and with a very small percent of cells in S-phase (0-5%). Nonetheless after 5-days of effective nucleoside analog therapy, there is a massive cytoreduction (1 to 3-log decrease). Our hypothesis is built around these premises to suggest that in addition to conventional S-phase mediated pathway, there may he additional pathways that result in non-S-phase cell death during therapy. To test this hypothesis, we want to pursue three specific aims that are focused toward different mode of cell death by analogs. First, we plan to define the elements of cell death caused by conventional DNA synthesis inhibition pathway during therapy. Using nelarabine and clofarabine, two of the most successful new nucleoside analogs in the clinic, we plan to investigate the role of cellular pharmacokinetics and cellular pharmacodynamics in cell death. These parameters will be compared with clinical response to these therapies. Second, we plan to identify mitochondria induced cell death of leukemia cells during therapy. Nucleoside analogs may affect mitochondria directly and/or indirectly to induce cell death in circulating leukemia cells during therapy. Direct effect such as mitochondrial respiratory function involving ATP synthase, adenosine nucleotide translocator (ANT), and early decrease in mitochondnal membrane potential will be accessed to elucidate the role of mitochondria induced apoptosis. Indirect effect will include release of cytochrome c, and late effect on membrane potential. Finally, we will investigate the role of receptor-mediated cell death of leukemia cells during therapy. Following our lead in cell lines that analog incorporation results in induction of fas ligand followed by fas-mediated cell death of non-Sphase population, we plan to pursue the role of fas in cell death during therapy. We feel that knowledge gained through these aims will assist us in designing optimal therapy of leukemia with nucleoside analogs.

描述（由申请人提供）：该提案是 CA57629 的延伸，重点是了解核苷类似物的代谢、作用机制和相互作用。随着类似物在白血病治疗中的成功率，包括我们在内的多个实验室已经研究了这些药物导致细胞死亡的机制。这些步骤包括形成类似物的三磷酸、掺入复制DNA、抑制核糖核苷酸还原酶（使用较新的类似物）以及最后抑制DNA合成。 DNA 合成的持续抑制会通过细胞凋亡导致细胞死亡。当在活跃地循环和复制 DNA 的细胞系中进行测试时，这种情况似乎就发生了。然而，当人们试图在治疗期间验证这一过程时，结果是矛盾且有趣的。体内白血病细胞的生物学特性与培养中的细胞系有很大不同。外周血中的白血病细胞通常是非循环或缓慢循环的，并且只有极少数细胞处于S期（0-5%）。尽管如此，经过 5 天有效的核苷类似物治疗后，细胞出现大量减少（减少 1 至 3 个对数）。我们的假设是围绕这些前提建立的，表明除了传统的 S 期介导途径外，可能还有其他途径导致治疗期间非 S 期细胞死亡。为了检验这一假设，我们想要追求三个具体目标，通过类似物关注不同的细胞死亡模式。首先，我们计划定义治疗期间常规DNA合成抑制途径引起的细胞死亡的要素。使用奈拉滨和氯法拉滨这两种临床上最成功的新型核苷类似物，我们计划研究细胞药代动力学和细胞药效学在细胞死亡中的作用。这些参数将与这些疗法的临床反应进行比较。其次，我们计划确定治疗期间线粒体诱导的白血病细胞的细胞死亡。核苷类似物可能直接和/或间接影响线粒体，以在治疗期间诱导循环白血病细胞的细胞死亡。将利用涉及 ATP 合成酶、腺苷核苷酸转位子 (ANT) 的线粒体呼吸功能和线粒体膜电位早期降低等直接效应来阐明线粒体诱导细胞凋亡的作用。间接影响包括细胞色素 c 的释放以及对膜电位的后期影响。最后，我们将研究治疗期间白血病细胞受体介导的细胞死亡的作用。继我们在细胞系中的领先地位之后，模拟掺入导致 fas 配体的诱导，随后由 fas 介导的非 Sphase 群体的细胞死亡，我们计划在治疗期间探究 fas 在细胞死亡中的作用。我们认为通过这些目标获得的知识将有助于我们设计核苷类似物治疗白血病的最佳疗法。

项目成果

Gemcitabine: metabolism, mechanisms of action, and self-potentiation.

• 发表时间: 1995-08
• 期刊: Seminars in oncology
• 影响因子: 4
• 作者: W. Plunkett;P. Huang;Y. Z. Xu;V. Heinemann;R. Grunewald;V. Gandhi

Incorporation of fludarabine and 1-beta-D-arabinofuranosylcytosine 5'-triphosphates by DNA polymerase alpha: affinity, interaction, and consequences.

DNA 聚合酶 α 掺入氟达拉滨和 1-β-D-阿拉伯呋喃糖基胞嘧啶 5-三磷酸：亲和力、相互作用和后果。

• 发表时间: 1997
• 期刊: Clinical cancer research : an official journal of the American Association for Cancer Research.
• 作者: Gandhi,V;Huang,P;Chapman,AJ;Chen,F;Plunkett,W
• 通讯作者: Plunkett,W

Cytotoxicity, metabolism, and mechanisms of action of 2',2'-difluorodeoxyguanosine in Chinese hamster ovary cells.

2,2-二氟脱氧鸟苷在中国仓鼠卵巢细胞中的细胞毒性、代谢和作用机制。

• 发表时间: 1995
• 期刊: Cancer research.
• 作者: Gandhi,V;Mineishi,S;Huang,P;Chapman,AJ;Yang,Y;Chen,F;Nowak,B;Chubb,S;Hertel,LW;Plunkett,W
• 通讯作者: Plunkett,W

Fludarabine for treatment of adult acute myelogenous leukemia.

氟达拉滨用于治疗成人急性髓性白血病。

• DOI: 10.3109/10428199309064255
• 发表时间: 1993
• 期刊: Leukemia & lymphoma
• 影响因子: 2.6
• 作者: Gandhi,V

Gemcitabine in hematologic malignancies.

吉西他滨治疗血液恶性肿瘤。

• DOI: 10.1097/00001622-200111000-00015
• 发表时间: 2001
• 期刊: Current opinion in oncology
• 影响因子: 3.4
• 作者: Nabhan,C;Krett,N;Gandhi,V;Rosen,S
• 通讯作者: Rosen,S