Although the C3435T polymorphism does not appear to be associated with other types of glioma, we cannot rule out that this MDR1 polymorphism may be associated with glioblastoma among men.
Brain vessels extracted from tissue sections of nonmalignant human brain and glioblastoma tumors by laser capture microdissection microscopy and analyzed by real-time polymerase chain reaction showed higher expression of ABCG2 relative to ABCB1/MDR1 and ABCC1/MRP1.
CD133, a putative stem cell marker in normal tissue and malignant brain tumors, enhances multidrug resistant gene 1 (MDR1) expression following chemotherapy in adult malignant glioblastomas.
Disappointing results in chemotherapy of glioblastomas resulting from multi-drug resistance (MDR) prompted us to investigate the influence of cytokine gene transfer in glioblastoma cells on the expression of P-glycoprotein and on chemosensitivity of transduced cells.
DTA0100 mitotic arrest properties were investigated in two multi-drug resistant cancer cell lines with P-glycoprotein overexpression (colorectal carcinoma and glioblastoma).
Here, we examined the role of the multidrug resistance (mdr) mechanism in the chemo-resistance of these tumors, using a twofold approach: (i) by assessing a possible mdr phenotype before and after chronic drug exposure of glioma cells in vitro, and (ii) by assessing the modulation of expression of the mdr-associated P-glycoprotein (Pgp) using radiotherapy and serial cycles of chemotherapy in human glioblastoma patients in vivo.
In conclusion, continuous PTX treatment caused the over-expression of P-gp and acquisition of MDR in colon cancer and glioblastoma cell lines, while some mechanisms of MDR and tumor progression such as GSH detoxification system and VEGF secretion were suppressed.
In conclusion, in patients with GBM receiving RCT with TMZ, no correlation with survival was found for the SNV:s 1236C>T, 2677G>T/A, and 3435C>T of ABCB1.
In the ANDnet, we furthermore identified potential glioma suppressor genes ACCN3 and ACCN4 linked to the NBPF1 neuroblastoma breakpoint family, as well as numerous ABC transporter genes (ABCA1, ABCB1) suggesting drug resistance of glioblastoma tumors.
In the present study, MDR1 P-gp was immunodetected by Western blot analysis in 60 human brain tumors, including meningiomas, schwannomas, low-grade gliomas (astrocytomas, pilocytic astrocytomas) and high-grade gliomas (anaplastic astrocytomas, glioblastomas and anaplastic oligodendrogliomas).
In this report, we show that the mdm2 (murine double minute 2) gene induced the expression of the mdr1 gene and P-gp in human glioblastoma U87-MG cells, which did not express the MDM2 protein or P-gp.
In this study, the activity of three new sulfocoumarins was evaluated in three sensitive and corresponding multidrug resistant cancer cell lines with increased P-glycoprotein expression (non-small cell lung carcinoma, colorectal carcinoma and glioblastoma).
No induction of mdr1 was observed in some early astrocytoma or glioblastoma cell cultures even after administration of high concentrations of the drugs ACNU and VM26, often used in glioma therapy.
NQO may be a priority target of glioblastoma chemotherapy suitable for biochemical nature of the cells, and expression analysis of NQO1, alpha-TUB, beta-TUB, MGMT, MDR1 and GSTpi may help to seek a truly active drug against glioblastomas.
Prognostic significance of the immunohistochemical expression of O6-methylguanine-DNA methyltransferase, P-glycoprotein, and multidrug resistance protein-1 in glioblastomas.
The aim of the present investigations was to reduce the expression of P-gp in the human glioblastoma cell line U-87 MG and in the human endothelial cell line HUV-ECC.
The efficacy of PI3K-mTOR inhibition was established using orthotopic allograft and genetically engineered spontaneous glioblastoma mouse models.<b>Results:</b> The mTOR inhibitors rapamycin and AZD8055 are substrates of ABCB1, whereas the dual PI3K/mTOR inhibitor NVP-BEZ235 and the PI3K inhibitor ZSTK474 are not.