title: Prognostic factors in malignant glioma: influence of the overexpression of oncogene and tumor-suppressor gene products on survival.
abstract: Despite the use of multimodal therapy, higher-grade glioma is still uniformly fatal in the adult population. There is a considerable difference between the length of survival in each given patient, even within the same tumor type and malignancy grade group, suggesting that there are factors that might differentially influence outcome. To identify such factors, 107 patients with anaplastic or malignant glioma were retrospectively investigated. Clinical parameters and paraclinical data on the p53, mdm2, and EGFR genes at the DNA or protein level were evaluated by univariate analysis and Cox proportional hazards regression modeling. Kaplan-Meier survival estimation demonstrated that immunohistochemical positivity for mdm2 protein in patients with anaplastic astrocytoma or with glioblastoma multiforme was associated with a shorter survival time (p = 0.02). P53 gene mutations and immunopositivity for the epidermal growth factor receptor (EGFR) protein were not significantly related to poor prognosis. The Cox proportional hazards model revealed immunohistochemical positivity for p53, mdm2, or for both of them, the presence of postoperative irradiation, and the extent of surgical resection of tumor to be variables significantly associated with prolonged survival. EGFR overexpression, age over 60 years, and Karnofsky performance score below 40 points did not significantly shorten survival time. In conclusion, the present study identified immunohistochemically detected mdm2-protein overexpression as a statistically significant negative prognostic parameter in patients bearing anaplastic or malignant glioma. Association analysis of variables revealed a possible correlation between mdm2 and p53, which is also consistent with the biological interaction mode of both proteins in vivo.
authors.affiliation: Department of Neurosurgery, Faculty of Medicine, Martin-Luther-University Halle-Wittenberg, Germany.
authors.forename: N G
authors.initials: NG
authors.lastname: Rainov
authors.forename: K U
authors.initials: KU
authors.lastname: Dobberstein
authors.forename: H
authors.initials: H
authors.lastname: Bahn
authors.forename: H J
authors.initials: HJ
authors.lastname: Holzhausen
authors.forename: C
authors.initials: C
authors.lastname: Lautenschläger
authors.forename: V
authors.initials: V
authors.lastname: Heidecke
authors.forename: W
authors.initials: W
authors.lastname: Burkert
mesh_terms: D000704:Analysis of Variance; D066246:ErbB Receptors / Q000032:analysis; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D016147:Genes, Tumor Suppressor; D016158:Genes, p53; D005909:Glioblastoma / Q000235:genetics* / Q000401:mortality; D006801:Humans; D007150:Immunohistochemistry; D009154:Mutation; D009857:Oncogenes; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate
chemical_list: D066246:ErbB Receptors