Sakano Shigeru, Matsumoto Hiroaki, Yamamoto Yoshiaki, Kawai Yoshihisa, Eguchi Satoshi, Ohmi Chietaka, Matsuyama Hideyasu, Naito Katsusuke
Department of Urology, Yamaguchi University School of Medicine, Ube, Japan.
Pathobiology. 2006;73(6):295-303. doi: 10.1159/000099124.
DNA repair enzymes play a vital role in protecting the genome from carcinogens, several of which can cause mutations in the TP53 gene in bladder cancer. Some single nucleotide polymorphisms (SNPs) in DNA repair genes reportedly modulate the repair capacity. This study aimed to clarify the effect of these functional SNPs on the alteration of p53 in muscle-invasive bladder cancer.
We investigated the association between SNPs in xeroderma pigmentosum complementation groups C (XPC), D and G and X-ray repair cross-complementing group 1 and 3 genes, and p53 expression and allelic imbalance at the TP53 locus in Japanese patients with muscle-invasive bladder cancer. p53 expression and the allelic imbalance were evaluated using immunohistochemistry and a microsatellite marker, respectively.
Positive p53 expression was significantly less frequent in patients with the CC genotype of the XPC gene than in those with the AA or AC genotype (p = 0.0005). C alleles of the XPC gene were also less frequent in patients with positive p53 expression (p = 0.01).
Our results suggested that the XPC polymorphism might affect p53 alteration and the molecular pathway defined by the p53 alteration in the development of muscle-invasive bladder cancer.
DNA修复酶在保护基因组免受致癌物侵害方面起着至关重要的作用,其中几种致癌物可导致膀胱癌中TP53基因发生突变。据报道,DNA修复基因中的一些单核苷酸多态性(SNP)可调节修复能力。本研究旨在阐明这些功能性SNP对肌层浸润性膀胱癌中p53改变的影响。
我们调查了日本肌层浸润性膀胱癌患者中着色性干皮病互补组C(XPC)、D和G以及X射线修复交叉互补组1和3基因中的SNP与p53表达及TP53基因座上等位基因失衡之间的关联。分别使用免疫组织化学和微卫星标记评估p53表达和等位基因失衡。
XPC基因CC基因型患者中p53阳性表达的频率显著低于AA或AC基因型患者(p = 0.0005)。p53阳性表达患者中XPC基因的C等位基因频率也较低(p = 0.01)。
我们的结果表明,XPC基因多态性可能影响p53改变以及肌层浸润性膀胱癌发生发展过程中由p53改变所定义的分子途径。