Estradiol and catecholestradiols as possible genotoxic carcinogens.
Estradiol and other estrogens are not classified as genotoxic carcinogens, but rather as tumor promoters in the multistage process of carcinogenesis. This study is a reexamination of the carcinogenic status of estradiol and the catecholestradiols (2-OHE2 and 4-OHE2) with the recently developed bacterial assays for genotoxic carcinogens, the Chromotest. The bacterial kits revealed estradiol and catecholestradiols as biphasic and potential genotoxic carcinogens with the following SOS inducing potency values: E2 43,265 (SD 8,300); 2-OHE2 30,153 (SD 2,500), and 4-OHE2 68,939 (SD 4,500). The differences between these values are statistically highly significant (p less than 0.0005). These results were confirmed by studies on Escherichia coli, which showed an increase in cell number and a stimulation of DNA content in the presence of the estrogens. It is therefore concluded that estradiol and the catecholestradiols are possible genotoxic carcinogens which probably act as tumor inducers rather than tumor promoters.
van Aswegen
C H
CH
Wolmarans Research Laboratory, Department of Urology, University of Pretoria, South Africa.
Nieuwoudt
L B
LB
van Rensburg
H G
HG
Steyn
P L
PL
du Plessis
D J
DJ
D002273:Carcinogens; D004269:DNA, Bacterial / Q000096:biosynthesis; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D004958:Estradiol / Q000633:toxicity*; D002393:Estrogens, Catechol / Q000633:toxicity*; D009152:Mutagenicity Tests; D009153:Mutagens; D011933:Reagent Kits, Diagnostic; D013014:SOS Response, Genetics
D002273:Carcinogens; D004269:DNA, Bacterial; D002393:Estrogens, Catechol; D009153:Mutagens; D011933:Reagent Kits, Diagnostic; D004958:Estradiol