In conclusion, this study demonstrates that concomitant TMZ together with radiation therapy increases GSM-patient survival independent of MGMT promoter methylation.
The O6-methylguanine-DNA methyltransferase promoter methylation studies were significantly more frequent in the GBMs than GSMs (80.1% vs. 44.7%, P < 0.001).
A study of clinico-pathological parameters and O⁶-methylguanine DNA methyltransferase (MGMT) promoter methylation status in the prognostication of gliosarcoma.
A study of clinico-pathological parameters and O⁶-methylguanine DNA methyltransferase (MGMT) promoter methylation status in the prognostication of gliosarcoma.
In the present study, we determined the status of MGMT using methylation-specific polymerase chain reaction (PCR) and immunohistochemistry on paraffin-embedded specimens in 12 human gliosarcomas, and these results were then related to overall survival (OS) and response to alkylating agents.
In the present study, we determined the status of MGMT using methylation-specific polymerase chain reaction (PCR) and immunohistochemistry on paraffin-embedded specimens in 12 human gliosarcomas, and these results were then related to overall survival (OS) and response to alkylating agents.
<b>Objective:</b> Gliosarcoma (GSC), a rare malignant brain tumor, is considered as a variant of isocitrate dehydrogenase 1 wild type (IDH1-WT) glioblastoma (GBM).
We provide the first comprehensive genome-wide genetic alternation profiling of GS, which suggests novel prognostic subgroups in GS patients based on their TP53 mutation status and provides new insight in the pathogenesis and targeted treatment of GS.
We identified a subset of tumors (n = 18, 8.8% of high-grade gliomas) exhibiting moderate-to-strong immunoreactivity that enriched for the IDH-wild-type glioblastoma variants gliosarcoma (n = 10) and the newly described epithelioid glioblastoma (n = 4).
Abnormalities identified by immunohistochemistry included p21 immunonegativity (60%, 25%, 93%), which was most frequent in TE-GBM (P = .008), strong nuclear p53 staining (29%, 29%, 41%), strong membranous staining for epidermal growth factor receptor (EGFR) (21%, 63%, 19%), which was most frequent in E-GBM (P = .03), and an increased frequency of p27 immunonegativity in gliosarcomas (15% negative, 85% focal) compared with tumors without sarcoma (38% strongly positive) (P = .009).
Single-strand conformation polymorphism followed by direct DNA sequencing revealed p53 mutations in five of 19 gliosarcomas (26%) and PTEN mutations in seven cases (37%).
As mutations of the p53 tumor suppressor gene represent an early event in the development of gliomas, we attempted to determine whether both components of gliosarcomas share identical alterations of the p53 gene.
Abnormalities identified by immunohistochemistry included p21 immunonegativity (60%, 25%, 93%), which was most frequent in TE-GBM (P = .008), strong nuclear p53 staining (29%, 29%, 41%), strong membranous staining for epidermal growth factor receptor (EGFR) (21%, 63%, 19%), which was most frequent in E-GBM (P = .03), and an increased frequency of p27 immunonegativity in gliosarcomas (15% negative, 85% focal) compared with tumors without sarcoma (38% strongly positive) (P = .009).
The aim of this study was to evaluate the effect of VEGF-A expression on tumor growth, perfusion, and chemotherapeutic efficacy in orthotopic 9L gliosarcomas.
Both genes are induced in biologically and genetically heterogenous glioblastoma cell lines (LN-229, LN-Z308, U87MG, T98G), whereas, in gliosarcoma cells (D247MG), only the VEGF gene is induced.