The antiandrogen flutamide inhibits growth of mcf-7 human breast-cancer cell-line

The role of androgens in experimental rodent mammary carcinogenesis

Breast cancer is currently the most frequent, fatal cancer of women in western countries. While estrogens have a widely understood involvement in breast cancer, a significant but not yet fully understood role for androgens has also been suggested. The principal androgen, testosterone, is the obligate steroidal precursor of estradiol, but can equally be metabolized into dihydrotestosterone, a more potent, pure androgen. Both androgens exert their distinctive biological effects via the androgen receptor, which is coexpressed with estrogen receptor alpha in 80 to 90% of breast cancers. The hormonal control of breast development and pathology has been examined experimentally through the use of animal models, notably mice and rats. This review summarizes the data from experimental rodent models on the effects of androgens in experimental breast cancer, aiming to address the importance of androgens and the androgen receptor in the origins and pathogenesis of breast cancers, as well as to discuss potential biomarker and therapeutic opportunities arising from novel insights based on the experimental research.

Prediction of cancer drugs by chemical-chemical interactions

Cancer, which is a leading cause of death worldwide, places a big burden on health-care system. In this study, an order-prediction model was built to predict a series of cancer drug indications based on chemical-chemical interactions. According to the confidence scores of their interactions, the order from the most likely cancer to the least one was obtained for each query drug. The 1(st) order prediction accuracy of the training dataset was 55.93%, evaluated by Jackknife test, while it was 55.56% and 59.09% on a validation test dataset and an independent test dataset, respectively. The proposed method outperformed a popular method based on molecular descriptors. Moreover, it was verified that some drugs were effective to the 'wrong' predicted indications, indicating that some 'wrong' drug indications were actually correct indications. Encouraged by the promising results, the method may become a useful tool to the prediction of drugs indications.

Inhibitory effect of hydroxyflutamide plus tamoxifen on oestradiol-induced growth of MCF-7 breast cancer cells

The antiandrogen flutamide has been reported to exert antiproliferative actions on breast cancer both in vitro and in vivo. Here we study the action of its active metabolite hydroxyflutamide on the oestradiol-induced growth of MCF-7 breast cancer cells. The results show that the antiandrogen inhibits the cell growth. Moreover hydroxyflutamide adds its antiproliferative effect to the action of the antioestrogen tamoxifen. The inhibitory effect is dose-dependent and it is unaffected by tamoxifen concentrations up to levels able to block oestrogen receptors completely. Dihydrotestosterone experiments parallel those on hydroxyflutamide. When the two substances are administered together, neither antagonistic nor additive effects are appreciable. Data are consistent with an androgen-like action of hydroxyflutamide on breast cancer cells. The antiproliferative effect of hydroxyflutamide, without virilizing side-effects, suggests that it is worth exploring its possible employment together with antioestrogens in the treatment of breast cancer patients.

Growth inhibition of DMBA-induced rat mammary carcinomas by the antiandrogen flutamide

Antiandrogens have sporadically been reported to exert antitumor activities in both pre- and post-menopausal breast cancer. To explore the possibility of using the pure antiandrogen flutamide (FLU) in breast cancer therapy, rats bearing DMBA-induced mammary tumors were treated with FLU, dihydrotestosterone (DHT), or FLU plus DHT. FLU was administered orally, at doses comparable to those used in the treatment of prostate cancer patients. FLU-treated animals had a significantly smaller average tumor area than controls from day 11 up to the end of the experiment (day 20). A similar reduction of tumor growth was observed in rats given DHT and in those treated with DHT plus FLU. Plasma levels of LH, FSH, P, 17-OH P, E2 and DHEA measured at the end of experiment did not differ between treated animals and controls. Results demonstrate that the antiandrogen FLU and the full androgen DHT exert similar inhibitory effects on the growth of dimethylbenz(a)anthracene (DMBA)-induced rat mammary tumors. Moreover, data show that plasma steroids levels are unaffected by FLU treatment. This finding rules out any antitumor effect dependent on the reduction of adrenal and gonadal steroidosynthesis, and makes it appear more likely that androgen receptors are involved in the antiproliferative effect of FLU.