Expression of multidrug-resistance P-glycoprotein (MDR1) in human brain tumors

✍ Scribed by Michel Demeule; Daniel Shedid; Édith Beaulieu; Rolando F. Del Maestro; Albert Moghrabi; Pierre B. Ghosn; Robert Moumdjian; France Berthelet; Richard Béliveau

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: French
• Weight: 129 KB
• Volume: 93
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.1306

✦ Synopsis

Multidrug resistance (MDR) is associated with the expression of P-glycoprotein (P-gp), an ATP-dependent transporter which expels anti-cancer drugs from cells. 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). Most samples from primary tumors expressed P-gp at the same levels as normal brain tissue except for schwannomas, in which levels were reduced by 65%, and meningiomas, in which levels were more than 10-fold higher in 7 of 10 samples. P-gp levels were 70% and 95% lower in brain metastases from melanomas and lung adenocarcinomas, respectively, than in normal brain tissue. These results indicate that the majority of primary brain tumors express MDR1 P-gp and that its high expression levels in meningiomas may be a marker for this type of brain tumor.