Sure U, Rüedi D, Tachibana O, Yonekawa Y, Ohgaki H, Kleihues P, Hegi M E
Institute of Neuropathology, University Hospital Zurich, Switzerland.
J Neuropathol Exp Neurol. 1997 Jul;56(7):782-9.
Glioblastoma multiforme is a rare neoplasm in children and is often located infratentorially, particularly in the brainstem: Pediatric glioblastomas arise frequently (here 60%) outside the cerebral hemispheres. We investigated 20 pediatric glioblastomas for mutational inactivation of the p53 tumor suppressor gene, loss of p16 protein expression and overexpression of the epidermal growth factor receptor (EGFR). Mutations in the p53 gene were identified in 5/20 (25%) glioblastomas, 4 of which occurred in primary glioblastomas with a clinical history of less than 4 months and neither clinical nor histologic evidence of a less malignant precursor lesion. Loss of p16 expression was detected in 11/18 (61%) glioblastomas. Overexpression of the EGFR was infrequent (2/19, 11%) and included 1 tumor with a p53 mutation. Of 4 secondary glioblastomas that progressed from histologically diagnosed lower grade tumors, one contained a p53 mutation. Our results are at variance with similar studies in adult patients in which primary and secondary glioblastomas are characterized by EGFR overexpression and p53 mutations, respectively, suggesting that the evolution of pediatric glioblastomas follows different genetic pathways.
多形性胶质母细胞瘤在儿童中是一种罕见的肿瘤，常位于幕下，尤其是在脑干：小儿胶质母细胞瘤常（此处为60%）发生于大脑半球以外。我们研究了20例小儿胶质母细胞瘤的p53肿瘤抑制基因突变失活、p16蛋白表达缺失及表皮生长因子受体（EGFR）过表达情况。在5/20（25%）的胶质母细胞瘤中发现了p53基因的突变，其中4例发生在临床病史少于4个月的原发性胶质母细胞瘤中，且无低级别恶性前体病变的临床及组织学证据。在11/18（61%）的胶质母细胞瘤中检测到p16表达缺失。EGFR过表达不常见（2/19，11%），其中1例肿瘤存在p53突变。在4例由组织学诊断的低级别肿瘤进展而来的继发性胶质母细胞瘤中，1例含有p53突变。我们的结果与成人患者的类似研究不同，在成人患者中，原发性和继发性胶质母细胞瘤分别以EGFR过表达和p53突变为特征，这表明小儿胶质母细胞瘤的发生发展遵循不同的遗传途径。
