Huang Bei, Starostik Petr, Kühl Joachim, Tonn Jörg C, Roggendorf Wolfgang
Department of Neuropathology, Institute of Pathology, Julius Maximilians Universität Würzburg, Josef-Schneider-Str. 2, 97080 Würzburg, Germany.
Acta Neuropathol. 2002 Apr;103(4):415-20. doi: 10.1007/s00401-001-0479-3. Epub 2002 Jan 17.
Ependymomas are glial tumors of the brain and spinal cord. The most frequent genetic change in sporadic ependymomas is monosomy 22, suggesting the presence of an ependymoma tumor suppressor gene on chromosome 22. Thirty-three pairs of matched normal and tumor specimens from ependymoma patients were genotyped using 12 polymorphic microsatellite markers spanning the long arm of chromosome 22. Allelic deletion was found in 12 of 33 tumors (36.4%). Eight tumors showed partial deletions and 4 tumors exhibited loss of the entire arm of 22q. We identified two common regions of deletion: one at 22q11.21-12.2 flanked by markers D22S420 and D22S300, and a second candidate region at 22q13.1-13.3 between D22S274 and D22S1149. The size of each region was 21.1 and 2.4 cM, respectively. Thus, our results suggest that one or more tumor suppressor genes associated with ependymoma may be present on chromosome 22. Comparison of these results with clinicopathological data indicate that allelic losses on 22q tend to occur more frequently in intracranial anaplastic ependymomas in children and intraspinal ependymomas in adults.
室管膜瘤是发生于脑和脊髓的神经胶质瘤。散发性室管膜瘤最常见的基因改变是22号染色体单体性，提示22号染色体上存在室管膜瘤肿瘤抑制基因。利用跨越22号染色体长臂的12个多态性微卫星标记，对33例室管膜瘤患者的配对正常和肿瘤标本进行基因分型。33个肿瘤中有12个（36.4%）发现等位基因缺失。8个肿瘤显示部分缺失，4个肿瘤表现为22q整条臂缺失。我们确定了两个常见的缺失区域：一个位于22q11.21 - 12.2，两侧为标记D22S420和D22S300；另一个候选区域位于22q13.1 - 13.3，在D22S274和D22S1149之间。每个区域的大小分别为21.1和2.4厘摩。因此，我们的结果提示22号染色体上可能存在一个或多个与室管膜瘤相关的肿瘤抑制基因。将这些结果与临床病理数据进行比较表明，22q等位基因缺失在儿童颅内间变性室管膜瘤和成人脊髓内室管膜瘤中更常发生。
