Expression of p53 and p21 in Primary Glioblastomas.

摘要: BACKGROUND AND PURPOSE: : Primary glioblastomas (GBMs) are highly radioresistant, and in contrast to secondary GBMs, they bear wild-type (wt) p53 protein, which is stabilized a proportion of these tumors. Therefore, it was investigated vivo whether expression has prognostic value patients undergoing radiochemotherapy. Additionally, the authors tried identify, vitro, subgroups primary GBM with different susceptibilities irradiation, on basis their p21 responses ionizing radiation. MATERIAL METHODS: Tumor tissue samples from 31 suffering combined radiochemotherapy topotecan were investigated. The percentage cells expressing protein determined immunohistochemically. cultures eleven GBMs established expressions evaluated before irradiation 10 Gy at 2 8 h after irradiation. measured by Western analysis mRNA reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: p53-positive within tumor specimens obtained ranged 0% 28%, median being 4.3%. No significant correlation disease-free survival or overall found. In detected seven GBM. After decrease seen six cultures. Half (two four) without basal showed an increase Basal overexpression cultures; four out led expression. all cell lines (five eleven) initially showing absent expression, induced Despite responses, G1 arrest not detectable any CONCLUSION: does correlate outcome content per se appear be helpful factor for prognosis-adapted therapy By contrast, vitro show independent pathways failure seems due functional defect pathway, either because unidentified downstream p21.