Troglitazone reduces glyoxalase i protein expression in glioma and potentiates the effects of chemotherapeutic agents

Despite resistance of most gliomas to chemotherapy,approximately 2/3 of oligodendrogliomas show sensitivity to such agents. this sensitivity has been associated with deletions on chromosome 1p alone or in combination with 19q. higher expression of the enzyme glyoxalase i has been found in oligodendrogliomas with chromosome 1p intact compared to those with a deletion. higher expression of this enzyme is also associated with tumor chemoresistance in other cancers. the present study tested whether the drug troglitazone would make a glioma cell line more sensitive to chemotherapeutic agents. this drug was chosen because it has been shown to decrease glyoxalase i enzyme activity in cells. treatment with troglitazone decreased expression of glyoxalase i,and potentiated cell death when used in combination with chemotherapeutic agents. this decrease in glyoxalase i protein may be one mechanism by which this potentiation occurs,and troglitazone may be a candidate for use in glioma therapy. © 2010 jeffrey helgager et al.