Ellagic [correction of ellagica] acid inhibits arylamine N-acetyltransferase activity and DNA adduct formation in human bladder tumor cell lines (T24 and TSGH 8301).
The fact that vitamin C (ascorbic acid) exhibits a protective effect in certain types of cancer is well documented. Our previous studies demonstrated that human bladder tumor cell line (T24) has N-acetyltransferase (NAT) activity in cytosols and intact cells. The present studies examined the inhibition of arylamine NAT activity and carcinogen (2-aminofluorene)-DNA adduct formation by ellagic acid (EA) in human bladder tumor cell lines (T24 and TSGH 8301). Two assay systems were performed, one with cellular cytosols (9,000 g supernatant), the other with intact bladder tumor cell suspensions. NAT activity and 2-aminofluorene-DNA adduct formation in T24 and TSGH 8301 cells was inhibited by EA in a dose-dependent manner in both systems, i.e.. the greater the concentration of EA in the reaction the greater the inhibition of NAT activity (dose- and time-course dependent effects). The data also indicated that EA decreased the apparent Km and Vmax of NAT enzymes from T24 and TSGH 8301 cells in cytosols. NAT activity and 2-aminofluorene-DNA adducts in T24 is higher than in TSGH 8301. This report is the first to demonstrate that EA affects human bladder tumor cell NAT activity.
Lin
S S
SS
Department of Radiological Technology, Chungtai Institute of Health Sciences and Technology, Taichung, Taiwan, Republic of China.
Hung
C F
CF
Tyan
Y S
YS
Yang
C C
CC
Hsia
T C
TC
Yang
M D
MD
Chung
J G
JG
D015073:2-Acetylaminofluorene / Q000031:analogs & derivatives* / Q000378:metabolism; D010129:4-Aminobenzoic Acid / Q000378:metabolism; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D001191:Arylamine N-Acetyltransferase / Q000037:antagonists & inhibitors*; D018736:DNA Adducts / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004610:Ellagic Acid / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005419:Flavonoids; D006801:Humans; D010636:Phenols / Q000494:pharmacology*; D011108:Polymers / Q000494:pharmacology*; D059808:Polyphenols; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism; D001749:Urinary Bladder Neoplasms
D000972:Antineoplastic Agents, Phytogenic; D018736:DNA Adducts; D004791:Enzyme Inhibitors; D005419:Flavonoids; D010636:Phenols; D011108:Polymers; D059808:Polyphenols; D004610:Ellagic Acid; D015073:2-Acetylaminofluorene; D001191:Arylamine N-Acetyltransferase; D010129:4-Aminobenzoic Acid