Cells lacking CIP1/WAF1 genes exhibit preferential sensitivity to cisplatin and nitrogen mustard
Cells lacking CIP1/WAF1 genes exhibit preferential sensitivity to cisplatin and nitrogen mustard
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DOI：
10.1038/sj.onc.1201052
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发表时间：
1997-05-08
期刊：
影响因子：
8
通讯作者：
OConnor, PM
中科院分区：
文献类型：
--
作者：
Fan, SJ;Chang, JK;OConnor, PM
我们先前已经表明，p53破坏使某些癌细胞类型对顺铂（CDDP）敏感（Fan等人，1995年）。在本研究中，我们研究了p53下游效应子p21的作用，（CIP 1/WAF 1）（p21），在该致敏中，在具有完整与破坏的p21基因的人结肠癌HCT-116细胞和鼠胚胎成纤维细胞（MEF）中进行研究。为了比较，还通过稳定转染人乳头瘤病毒16型E6基因制备了缺乏p53功能的HCT-116细胞。发现HCT-116/E6细胞比对照转染子对CDDP和另一种DNA交联剂氮芥（HN 2）更敏感。p21基因被破坏的HCT-116细胞也表现出比亲本HCT-116细胞更高的CDDP和HN 2敏感性。与此相反，HCT-116细胞暴露于电离辐射，阿霉素，紫杉醇或长春新碱的克隆存活不受p53或p21破坏。HCT-116/p21（-/-）细胞对CDDP和HN 2的敏感性不限于HCT-116细胞背景，因为来自p21敲除小鼠的MEF也对这些DNA交联剂更敏感。对这种增强的敏感性的可能原因的调查显示，缺乏p53或p21功能的HCT-116细胞表现出修复转染到细胞中的顺铂损伤的CAT报告质粒的能力降低。另外，我们发现HCT-116/p21（-/-）细胞比亲本细胞更容易受到HN 2诱导的细胞周期延迟。我们的研究结果表明，p21中断优先敏感至少某些细胞类型的DNA交联剂。
We have previously shown that p53 disruption sensitizes certain cancer cell types to cisplatin (CDDP) (Fan et al., 1995). In the present study we investigated the role of the p53 downstream effector, p21(CIP1/WAF1) (p21), in this sensitization, Studies were performed in human colon cancer HCT-116 cells and murine embryonic fibroblasts (MEF) with intact versus disrupted p21 genes, For comparison, HCT-116 cells lacking p53 function were also prepared through stable transfection with the human papillomavirus type-16 E6 gene. HCT-116/E6 cells were found to be more sensitive than control transfectants to CDDP and another DNA crosslinking agent, nitrogen mustard (HN2). HCT-116 cells with disrupted p21 genes also exhibited greater CDDP and HN2-sensitivity than parental HCT-116 cells. In contrast, the clonogenic survival of HCT-116 cells exposed to ionizing radiation, adriamycin, taxol or vincristine was not affected by p53 or p21 disruption. Sensitization of HCT-116/p21(-/-) cells to CDDP and HN2 was not limited to the HCT-116 cell background since MEF from p21 knockout mice were also more sensitive to these DNA crosslinking agents. Investigations into a possible cause of this enhanced sensitivity revealed that HCT-116 cells lacking p53 or p21 function exhibited a reduced ability to repair cisplatin-damaged CAT-reporter plasmids transfected into the cells. In addition, we found that HCT-116/p21(-/-) cells were much more susceptible to HN2-induced cell cycle delay than parental cells. Our results suggest that p21 disruption preferentially sensitizes at least some cell types to DNA crosslinking agents.