Reduction of DNA damage by interaction s of dietary compounds with DNA.
Poster Number
5
Format
Poster Presentation
Abstract/Artist Statement
Plant-derived dietary compounds and supplements are potential sources of chemicals that reduce cancer risk. The purpose of this study was to examine the effect of genistein, a soy-derived isoflavone, on DNA adduct formation. Cisplatin, a DNA damaging agent used in anti-cancer treatment, was selected as a model for assaying genotoxicity in vitro. Since DNA damage frequently occurs at "hotspot" sequences, we chose the human p53 gene (exon 7 - 9) as "hotspot" target DNA. Target and excess of carrier DNA were incubated with cisplatin in the presence of genistein or control chemicals overnight at 37°C in buffered saline solution. The extent of DNA damage was detected by a polymerase chain reaction (PCR) and agarose gel electrophoresis assay developed for this purpose. Reduction in the amount of a p53-specific PCR product was taken as evidence of DNA damage. Genistein was found to negatively affect cisplatin-induced DNA damage. A significant retention of band intensity was observed at 2 mM genistein. Quercetin, another plant-derived flavone had a similar effect at the same concentration. The intercalator ethidium bromide also restored band intensity, indicating intercalation could be a mechanism involved in DNA damage reduction by flavones and isoflavones.
Location
Pacific Geosciences Center
Start Date
26-4-2003 9:00 AM
End Date
26-4-2003 5:00 PM
Reduction of DNA damage by interaction s of dietary compounds with DNA.
Pacific Geosciences Center
Plant-derived dietary compounds and supplements are potential sources of chemicals that reduce cancer risk. The purpose of this study was to examine the effect of genistein, a soy-derived isoflavone, on DNA adduct formation. Cisplatin, a DNA damaging agent used in anti-cancer treatment, was selected as a model for assaying genotoxicity in vitro. Since DNA damage frequently occurs at "hotspot" sequences, we chose the human p53 gene (exon 7 - 9) as "hotspot" target DNA. Target and excess of carrier DNA were incubated with cisplatin in the presence of genistein or control chemicals overnight at 37°C in buffered saline solution. The extent of DNA damage was detected by a polymerase chain reaction (PCR) and agarose gel electrophoresis assay developed for this purpose. Reduction in the amount of a p53-specific PCR product was taken as evidence of DNA damage. Genistein was found to negatively affect cisplatin-induced DNA damage. A significant retention of band intensity was observed at 2 mM genistein. Quercetin, another plant-derived flavone had a similar effect at the same concentration. The intercalator ethidium bromide also restored band intensity, indicating intercalation could be a mechanism involved in DNA damage reduction by flavones and isoflavones.