Suzuki S O, Iwaki T
Department of Neuropathology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Mod Pathol. 2000 May;13(5):548-53. doi: 10.1038/modpathol.3880095.
Ependymomas rarely show p53 gene alteration, and the tumorigenic mechanism of ependymomas still remains to be elucidated. We investigated the amplification and overexpression of mdm2 gene, whose product (MDM2) is considered to be one of the major cellular regulators of p53-mediated growth control, in 26 specimens of ependymomas obtained from 20 patients. The majority of the ependymomatous samples (96%) showed at least focal immunopositivity for MDM2; however, only 8% of the samples were immunopositive for p53. mdm2 gene amplification was detected in 35% of the samples by differential polymerase chain reaction, all of which overexpressed MDM2. These results suggest that the amplification and/or overexpression of mdm2 may be one of the major molecular events occurring in the tumorigenesis of ependymomas.
室管膜瘤很少出现p53基因改变，其致瘤机制仍有待阐明。我们研究了mdm2基因的扩增和过表达情况，其产物（MDM2）被认为是p53介导的生长调控的主要细胞调节因子之一，研究对象为从20例患者获取的26例室管膜瘤标本。大多数室管膜瘤样本（96%）至少对MDM2呈局灶性免疫阳性；然而，只有8%的样本对p53呈免疫阳性。通过差异聚合酶链反应在35%的样本中检测到mdm2基因扩增，所有这些样本均过表达MDM2。这些结果表明，mdm2的扩增和/或过表达可能是室管膜瘤发生过程中发生的主要分子事件之一。
