Human MCF-7 cells

DNA breaks in human MCF-7 cells [65], Damaging effect of menadione was probably mediated by hydroxyl radicals as it was demonstrated by ESR spin-trapping method. The analogs of menadione 2-methylmethoxynaphthoquinone and 2-chloromethylnaphtho-quinone also stimulated DNA damage through the formation of superoxide and other free radicals [66]. Similar effects have been shown for hydroquinone, catechol, benzoquinone, and benzenetriol [67,68]. 

Effect of Estradiol on Human MCF-7 Cells in vivo. Cancer Res. 44, 2654—2659 (1984). 

Chen, W.-J., Armour, S., Way, J., Chen, G., Watson, C., Irving, P., Cobb, J., Kadwell, S., Beaumont, K., Rimele, T., and Kenakin, T. P. (1997). Expression cloning and receptor pharmacology of human calcitonin receptors from MCF-7 cells and their relationship to amylin receptors. Mol. Pharmacol. 52 1164-1175. 

HSIEH c Y, SANTELL R c, HASLAM s z, HELFERICH w G (1998) Estrogenic effects of genistein on the growth of estrogen receptor-positive human breast cancer (MCF-7) cells in vitro and in vivo. Cancer Res. 58 3883-3838. 

YCUNG H J, DCERGE D R, KIMBERLY F A, ALLRED C D and HELFERICH W G (2002) Dietary genistein negates the inhibitory effect of tamoxifen on growth of estrogen-dependent human breast cancer (MCF-7) cells implanted in athymic mice. Cancer Res 62,2474-77. 

Doyle LA, Yang W, Abruzzo LV, Krog-mann T, Gao Y, Rishi AK et al. A multidrug resistance transporter from human MCF-7 breast cancer cells. Proc Natl Acad Sci USA 1998 95(26) 15665-15670. 

Miproxifene (TAT-59) is a prodrug of 4-hydroxy-tamoxifen that has been developed for tamoxifen-resistant carcinoma, but relatively little information has been published on this drug. Compared with tamoxifen, miproxifene inhibits estradiol-stimulated proliferation of MCF-7 cells at a threefold lower dose than that of tamoxifen, and of dimethyl-benzanthracene (DMBA)-induced rat mammary tumors at a dose tenfold lower than tamoxifen (Toko et al. 1990). In any event, in preclinical castrated rat models, it shows an endometrial stimulation activity that is similar to that of tamoxifen, which means it has limited potential use in the prevention or treatment of osteoporosis or cardiovascular disease (Shibata et al. 2000). Similarly, considering the preclinical findings of endometrial stimulation reported on GW5638 (Willson et al. 1997), it is likely that this new SERM belonging to the triphenylethylene family will be limited in clinical use to the treatment of advanced tamoxifen-resistant breast cancer once its efficacy is demonstrated in human clinical trials. 

When used in tumor cells, fulvestrant was initially described as a potent, competitive growth inhibitor of ER-positive, human breast cancer MCF-7 cells, whose growth is stimulated by estradiol. The compound was ineffective in tumor cell lines without ER, such as MDA-MB-231. The inhibitory effects were more pronounced with fulvestrant than with tamoxifen in the same cell line (Wakeling et al. 1991). 

In MDR cells, a significant fraction of P-gp is found associated with caveolin-rich membranes, and there is a substantial increase in the number of caveolae and caveolin-1 protein level. For example, both multidrug resistant human colon adenocarcinoma HT-29 cells and adriamycin-resistant breast adenocarcinoma MCF-7 cells display about a 12-fold increase in caveolin expression, which correlates with an approximate fivefold increase in morphologically identifiable caveolae [55], In addition, these cells exhibit increased amounts of phospholipase D and lipids such as cholesterol, glucosylceramide, and sphingomyelin [56, 57], Similarly, taxol-resistant A549 cells display both increased caveolin expression and caveolae numbers [58], While these correlations track with MDR, they do not suggest a simple mechanism for the role of... 

Radicicol (11) isolated from C. chiversii was able to deplete cellular levels of the known Hsp90 client proteins ER and IGF-IR in MCF-7 human breast cancer cells. An IC50 value of 0.03 xM was obtained for the proliferation of MCF-7 cells treated with radicicol for three days. Currently, clinical trials are in progress with a less toxic CDA derivative, allylamino-17-demethoxygeldanamycin (17-AAC) (19). ... 

Huang Y, Ray S, Reed JC, et al. Estrogen increases intracellular p26Bcl-2 to p21Bax ratios and inhibits taxol-induced apoptosis of human breast cancer MCF-7 cells. Breast Cancer Res Treat 1997 42( 1 ) 73—81. 

DFBcPh and its dihydrodiol were subjected to metabolism, and the extent of DNA binding in human breast cancer MCF-7 cells was assessed." The extent of DNA binding was then compared with that for BcPh and its dihydrodiol and the potent carcinogen BaP. The 1,4-DFBcPh series 2 (anti) DE-derived DNA adducts were also compared with those arising from intracellular oxidation of the dihydrodiol with subsequent DNA binding. These experiments showed that increased molecular distortion decreased metabolic activation to the terminal metabolites but the DE metabolites formed were the DNA-damaging species. 

Sathyamoorthy N, Wang TT. Differential effects of dietary phyto-oestrogens daidzein and equol on human breast cancer MCF-7 cells. Eur. J. Cancer 33, 2384-2389, 1997. 

Based on the same principle of modulation of drug absorption, other less known botanicals could produce similar or different effects compared to St. John s wort. Rosemary (Rosemarinus officinalis Labiatae) is a commonly used dietary botanical that has been found to have a chemopreventive effect (24). Furthermore, in drug-resistant MCF-7 human breast cancer cells expressing P-glycoprotein, methanol extracts of Rosemary at two concentrations (16.5 and 85 pg/mL) inhibited the efflux and increased intracellular accumulation of doxorubicin and vinblastine, two chemotherapeutic drugs that are known substrates of P-glycoprotein. Treatment of drug-resistant cells with the extracts also increased the cytotoxic effects of doxorubicin. On the other hand, in wild-type MCF-7 cells that do not express... 

Guilbaud, N.F., Gas, N., Dupont, M.A. Valette, A. (1990) Effects of differentiation-inducing agents on maturation of human MCF-7 breast cancer cells. J. cell. Physiol., 145, 162-172... 

Kim YA, Choi BT, Lee YT, Park DI, Rhee SH, Park KY, Choi YH. 2004. Resveratrol inhibits cell proliferation and induces apoptosis of human breast carcinoma MCF-7 cells. Oncol Rep 11 441-446. 

Yoon H, Liu RH. 2007. Effect of selected phytochemicals and apple extracts on NF-kappaB activation in human breast cancer MCF-7 cells. J Agric Food Chem 55 3167-3173. 

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