Genotoxic effects of the novel mixed antiestrogen FC-1271a in comparison to tamoxifen and toremifene

@article{HellmannBlumberg2000GenotoxicEO,
  title={Genotoxic effects of the novel mixed antiestrogen FC-1271a in comparison to tamoxifen and toremifene},
  author={Utha Hellmann-Blumberg and Tracy L. Taras and Gregory T. Wurz and Michael W. DeGregorio},
  journal={Breast Cancer Research and Treatment},
  year={2000},
  volume={60},
  pages={63-70}
}
Tamoxifen has been used for the treatment of breast cancer since the 1970s, but is considered a carcinogen because it has been linked to liver cancer in rats and an increased risk of endometrial cancer in patients. In rats, DNA adducts appear to be responsible for carcinogenesis, but their contribution to carcinogenesis in humans is not clear. FC-1271a and toremifene are mixed antiestrogens similar to tamoxifen. In order to compare the genotoxicity of these different triphenylethylenes, we… 
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36 Citations
Background Citations
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Methods Citations
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Results Citations
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36 Citations

Ospemifene inhibits the growth of dimethylbenzanthracene-induced mammary tumors in Sencar mice

Formation of tamoxifen-DNA adducts in multiple organs of adult female cynomolgus monkeys dosed with tamoxifen for 30 days.

It is indicated that cynomolgus monkeys are capable of metabolizing TAM to genotoxic intermediates that form TAM-DNA adducts in multiple tissues, as well as on-line sample preparation and high-performance liquid chromatography (HPLC).

Ospemifene and 4-hydroxyospemifene effectively prevent and treat breast cancer in the MTag.Tg transgenic mouse model

Ospemifene does not seem to pose a breast cancer risk in animals and slows down cancer development and progression in the MTag.Tg model, and does not exert an estrogenic effect in the breast tissue at doses equivalent to human dosing.

Effect of Coenzyme Q10, Riboflavin and Niacin on Tamoxifen treated postmenopausal breast cancer women with special reference to blood chemistry profiles

TAM on co-administration with CoRN has a favorable impact on various blood chemistry profiles, however, large scale randomized studies over a longer time span are required to ascertain the safety and efficacy of co- Administrating antioxidants with conventional chemotherapy.

The effects of selective oestrogen receptor modulators in the uterus

It is concluded that not all oestrogens agonists are the same in this model and while oestrogenicity is needed for the development of adenomyosis additional, unidentified factors, are required.

New insights into the metabolism of tamoxifen and its role in the treatment and prevention of breast cancer

Metabolites of Tamoxifen as the Basis of Drug Development

Tamoxifen is a prodrug but it is the metabolite 4-hydroxy-N-desmethyltam Oxifen or endoxifens that has attracted pharmacogenetic interest.

The effect of dimethyl dimethoxy biphenyl dicarboxylate (DDB) against tamoxifen-induced liver injury in rats: DDB use is curative or protective.

The oral administration of DDB in a dose of 200 mg/kg body weight daily for 10 successive days resulted in alleviation of the oxidative stress status of tamoxifen-intoxicated liver injury in rats as observed by significant increments in the antioxidant enzymes.

Estrogen receptors as therapeutic targets in breast cancer.

The development of resistance to endocrine therapy remains a clinically important problem, and laboratory models based on human breast cancer cells grown as tumors in immune-compromised mice have led to important insights into this problem.

Effects of ospemifene, a novel selective estrogen-receptor modulator, on human breast tissue ex vivo

Osp inhibited proliferation and opposed E2 stimulation in normal HBT in an efficacious, but less potent way than Ral and Tam, and the ESR1 PvuII polymorphisms may influence the responsiveness of HBT to E2 and SERMs.

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