Decreased nuclear matrix DNA topoisomerase II in human leukemia cells resistant to VM-26 and m-AMSA.
Decreased nuclear matrix DNA topoisomerase II in human leukemia cells resistant to VM-26 and m-AMSA.
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对 VM-26 和 m-AMSA 耐药的人白血病细胞中核基质 DNA 拓扑异构酶 II 减少。
DOI：
10.1021/bi00469a028
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发表时间：
1990
期刊：
影响因子：
2.9
通讯作者：
Beck,WT
中科院分区：
文献类型：
--
作者：
Fernandes,DJ;Danks,MK;Beck,WT
选择对VM-26 （CEM/VM-1）具有抗性的CEM白血病细胞对各种其他DNA拓扑异构酶II抑制剂具有交叉抗性，但对长春花生物碱没有交叉抗性。由于DNA拓扑异构酶II是核基质的主要蛋白质，我们想知道核基质拓扑异构酶II的改变是否在这种形式的多药耐药中很重要。用5 pM VM-26或3 m-AMSA预处理药物敏感CEM细胞2小时，与散装DNA相比，新复制DNA在核基质上的特异性活性分别降低了75%和50%。然而，VM-26和m-AMSA均不影响从耐药CEM/VM-1细胞核基质中分离的新生DNA的相对特异性活性。与亲代CEM细胞相比，CEM/VM-1细胞的核基质制备中dna拓扑异构酶II的十烷化和解结活性分别降低了6倍和7倍。Westernblot分析显示，与CEM细胞相比，CEM/VM-1细胞的核基质中免疫反应性拓扑异构酶II的数量减少了3.2倍，但这些细胞系的细胞核非基质（1.5 M盐溶性）部分的酶含量没有显著差异。将基质分离过程中使用的NaCl浓度从0.2 M增加到1.8 M，导致CEM/VM-1基质中拓扑异构酶II的比活性逐渐降低，但CEM细胞中没有，这表明酶与基质的结合在抗性细胞中发生了改变。这些数据支持了对VM-26和m-AMSA的抗性与核基质拓扑异构酶II活性降低直接相关的假设。在CEM/VM-1细胞中，VM-26或m-AMSA与核基质拓扑异构酶II的相互作用明显减弱。人类肿瘤细胞选择对一种天然产物药物产生耐药性，往往导致对其他结构和细胞毒性机制不同的天然产物药物产生耐药性。这种类型的耐药性发生在体外和体内[参见Beck（1987）、Endicott和Ling（1989）以及van der Bliek和Borst(1989)]，被称为耐多药耐药。例如，在选择对长春花生物碱具有抗性的细胞中，已经证明了对表观叶绿素毒素和DNA嵌入剂的交叉抗性（Beck, 1984）。最广泛表征的MDR （Pgp-MDR）形式与稳态药物水平降低和p-糖蛋白表达增加有关，p-糖蛋白是导致表型的因素（Bradley等，1988;Pastan & Gottesman, 1988）。
CEM leukemia cells selected for resistance to VM-26 (CEM/VM-1) are cross-resistant to various other DNA topoisomerase II inhibitors but not toVinca alkaloids. Since DNA topoisomerase II is a major protein of the nuclear matrix, we asked if alterations in nuclear matrix topoisomerase II might be important in this form of multidrug resistance. Pretreatment of drug-sensitive CEM cells for 2 h with either 5 pM VM-26 or 3 m-AMSA reduced the specific activity of newly replicated DNA on the nuclear matrix by 75 and 50%, respectively, relative to that of the bulk DNA. However, neither VM-26 nor m-AMSA affected the relative specific activity of nascent DNA isolated from the nuclear matrices of drug-resistant CEM/VM-1 cells. The decatenating and unknotting activities ofDNA topoisomerase II were 6-and 7-fold lower, respectively, in the nuclear matrix preparations from the CEM/VM-1 cells compared to parental CEM cells. Westernblot analysisrevealed that the amount of immunoreactive topoisomerase II in the nuclear matrices of the CEM/VM-1 cells was decreased 3.2-fold relative to that in CEM cells, but there was no significant difference inthe amount of enzyme present in the nonmatrix (1.5 M salt soluble) fractions of nuclei from these cell lines. Increasing the NaCl concentration used in the matrix isolationprocedure from 0.2 to 1.8 M resulted in a progressive decrease in the specific activity of topoisomerase II in matrices of CEM/VM-1 but not CEM cells, which suggested that the association of the enzyme with the matrix is altered in the resistant cells. These data support the hypothesis that resistance to VM-26 and m-AMSA is directly related to the decreased activity of nuclear matrix topoisomerase II. In CEM/VM-1 cells the interaction of either VM-26 or m-AMSA with nuclear matrix topoisomerase II is specifically diminished.Selection of human tumor cells for resistance to one natural product drug frequently results in resistance to other natural product drugs that are dissimilar in structure and apparent mechanism of cytotoxicity. This type of resistance occurs in vitro and in vivo [reviewed in Beck (1987), Endicott and Ling (1989) and van der Bliek and Borst (1989)] and is termed MDR. 1 For example, cross-resistance to the epipodophyllotoxins and DNA intercalating agents has been demonstrated in cells selected for resistance to the Vinca alkaloids (Beck, 1984). The most extensively characterizedform of MDR (Pgp-MDR) is associated with decreased steady-statedrug levels and increased expression of an integral plasma mem-brane glycoprotein, P-glycoprotein, which is responsible for the phenotype (Bradley et al., 1988; Pastan & Gottesman, 1988).
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长春花生物碱耐药性的细胞药理学及其规避。
DOI：
10.1016/0065-2571(84)90015-3
发表时间：
1984
期刊：
Advances in enzyme regulation
影响因子：
--
作者：
Beck,WT
通讯作者：
Beck,WT
4-(9-吖啶基氨基)-甲磺酰-间苯胺和伽马射线诱导的 DNA-蛋白质交联的比较。
影响因子：
11.2
作者：
Chiu,SM;Xue,LY;Friedman,LR;Oleinick,NL
通讯作者：
Oleinick,NL
影响因子：
11.2
作者：
Bonnie S. Glisson;Radhey S. Gupta;Radhey S. Gupta;S. Smallwood-Kentro;S. Smallwood-Kentro;W. Ross
通讯作者：
Bonnie S. Glisson;Radhey S. Gupta;Radhey S. Gupta;S. Smallwood-Kentro;S. Smallwood-Kentro;W. Ross
超螺旋环和真核 DNA 复制
影响因子：
64.5
作者：
B. Vogelstein;D. Pardoll;D. S. Coffey
通讯作者：
D. S. Coffey
影响因子：
64.8
作者：
W. Nelson;Leroy F. Liu;D. S. Coffey
通讯作者：
W. Nelson;Leroy F. Liu;D. S. Coffey