Human CD9 (TSPAN29/MRP-1), a close homolog of tsp2A, was found to be expressed in glioma cell lines A172 and U343MG as well as in the majority of glioblastoma samples (16/22, 73 %).
In conclusion, after Etoposide intervention glioblastoma stem-like cells showed a stronger resistance to apoptosis and death, and the anti-apoptotic gene livinbeta was more related with the high survival rate and MRP1 appeared to be more related with transporting chemotherapeutics out of glioblastoma stem-like cells.
Univariate analysis of collected data demonstrated that the expressions of O(6)-MGMT and MRP-1 detected by immunohistochemistry, in addition to the consistent factors, including preoperative Karnofsky performance scale (KPS), radical surgery, and tumor location and extension, were significant prognostic factors for the overall survival (OS) of patients with glioblastoma, who received nimustine (ACNU)-based chemotherapy in association with surgery and radiotherapy.
The properties of glioblastoma and astrocytoma stem-like cells on anti-apoptotic and MRP genes are: anti-apoptotic gene livin and survivin are elevated in CSCs but are the most increased in just differentiated CSCs; MRP1 gene is significantly increased and MRP3 is decreased in CSCs, but when differentiating the MRP3 gene starts a remarkable increase in CSCs; the expression of anti-apoptotic and MRP genes shows no differences between the CSCs isolated from glioblastoma and astrocytoma tissues.
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.
Furthermore, our results that exhibit protein expression of MRP1 and MRP3 and gene expression of MRP4 and MRP5 in these 2 glioblastoma cell lines suggest new mechanisms that could lead to a MDR phenotype of tumour cells in patients with glioblastoma multiforme.