Department of Pharmacology
DNA; *DNA Glycosylases; Drug Resistance; Ethylnitrosourea; Glioma; N-Glycosyl Hydrolases; Tumor Cells, Cultured
Genetics and Genomics | Medical Pharmacology | Pharmacology
Extracts of a glial cell line (SF-126) which is sensitive to the cytotoxic effect of the haloethylnitrosoureas and of a cell line (SF-188) which is resistant to these agents have been tested for their ability to release methylated bases from a DNA substrate which has been modified with [3H]dimethyl sulfate. In comparison with the sensitive cell line, extracts from the resistant cell line have 2-3-fold higher enzymatic activity. High performance liquid chromatography profiles of the bases which are released by these extracts show that the activity is specific for 3-methyladenine, suggesting that the resistant cells contain elevated levels of 3-methyladenine DNA glycosylase. Previous studies have shown that these cells also contain elevated levels of O6-alkylguanine-DNA alkyl-transferase, suggesting that both enzyme activities may be involved in the resistance of this cell line to the haloethylnitrosoureas.
Cancer Res. 1991 Mar 1;51(5):1568-70.
Matijasevic, Zdenka; Bodell, William J.; and Ludlum, David B., "3-Methyladenine DNA glycosylase activity in a glial cell line sensitive to the haloethylnitrosoureas in comparison with a resistant cell line" (1991). Open Access Articles. 375.