Silencing of the p53R2 gene by RNA interference inhibits growth and enhances 5-fluorouracil sensitivity of oral cancer cells
Silencing of the p53R2 gene by RNA interference inhibits growth and enhances 5-fluorouracil sensitivity of oral cancer cells
复制标题
DOI：
10.1016/j.canlet.2004.10.019
复制
发表时间：
2005-06-01
期刊：
影响因子：
9.7
通讯作者：
Mizuno, A
中科院分区：
文献类型：
--
作者：
Yanamoto, S;Iwamoto, T;Mizuno, A
p53 R2基因编码核糖核苷酸还原酶（RR）小亚基2同源物，并由几种激活p53的应激信号（如DNA损伤剂）诱导。p53 R2基因产物导致细胞核中脱氧核苷酸三磷酸（dNTP）库的增加，这有助于DNA修复和合成。我们推测p53 R2将是一个很好的肿瘤基因治疗的分子靶点。在这项研究中，测试了三种人口腔癌细胞系（SAS、HSC-4和Ca 9 -22）、一种人乳腺癌细胞系MCF-7和一种正常人成纤维细胞系NHDF。我们用高度特异性的转录后抑制RNA干扰（RNAi）技术沉默了p53 R2的表达。采用逆转录-聚合酶链反应（RT-PCR）和Western blotting检测p53 R2的表达。通过3-（4，5-二甲基噻唑-2-基）-2，5-二苯基溴化四氮唑（MTT）测定评价对抗癌剂的敏感性。p53 R2的表达与p53突变状态无关。p53 R2高表达的癌细胞对5-FU耐药率高。RNAi介导的p53 R2减少选择性抑制癌细胞系的生长并增强化疗敏感性，但在正常成纤维细胞中不存在。这些结果表明，p53 R2的基础转录可能与抗癌药物的敏感性。此外，我们评估了p53 R2将是一个很好的分子靶点的可能性，并报告了针对p53 R2的RNAi可能用于口腔癌基因治疗。(c)2004爱思唯尔爱尔兰有限公司保留所有权利。
The p53R2 gene encodes the ribonucleotide reductase (RR) small subunit 2 homologue, and is induced by several stress signals activating p53, such as DNA-damaging agents. The p53R2 gene product causes an increase in the deoxynucleotide triphosphate (dNTP) pool in the nucleus, which facilitates DNA repair and synthesis. We hypothesized that p53R2 would be a good molecular target for cancer gene therapy. In this study, three human oral cancer cell lines (SAS, HSC-4 and Ca9-22), a human breast cancer cell line MCF-7, and a normal human fibroblast cell line NHDF were tested. We silenced the expression of p53R2 with the highly specific post-transcriptional suppression of RNA interference (RNAi). We investigated p53R2 expression with the reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. The sensitivity to anticancer agents was evaluated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression of p53R2 showed no association with the mutational status of p53. The cancer cell lines with higher p53R2 expression were more resistant to 5-FU. RNAi-mediated p53R2 reduction selectivity inhibited growth and enhanced chemosensitivity in cancer cell lines but not in normal fibroblasts. These results suggest that basal transcription of p53R2 could be associated with the sensitivity to anticancer agents. Moreover, we assessed the possibility that p53R2 would be a good molecular target, and report that RNAi targeting of p53R2 could be useful for oral cancer gene therapy. (c) 2004 Elsevier Ireland Ltd. All rights reserved.