Breast cancer hormone dependency

Post-menopausal breast cancers yield splendidly to treatment with oestrogens, whereas a common type of pre-menopausal breast cancer is actually stimulated by them and, in addition, can convert androgens to oestrogens (Brule et al,y 1973). However, about one third of pre-meno-pausal breast cancers are dependent on a pituitary hormone, prolactin. 

Noncontraceptive Uses of Progestins. Progestins have other therapeutic uses aside from contraception. Hormone-dependent tumors and cysts involving reproductive tissues respond to progestins. Megestrol acetate and MPA are the two most commonly used progestins to treat breast cancer... 

A stmcturally related series of phenyfiiydrazones resulted ia the selection of compound A-007 [2675-35-6] (DEKK-TEC)(37) for the treatment of hormone-dependent tumors. A-007 is an antiestrogen that, ia contrast to tamoxifen, demonstrated inhibitory activity both ia the presence and absence of estradiol ia ZR-75-1 estrogen-dependent human breast cancer cells, and afforded more protection than tamoxifen ia the 7,12-dimethylbenz[i7]anthracene... 

Breast Cancer. Many studies have observed low incidences of hormone-dependent cancers, particularly breast cancer, in Asian countries compared with Western countries and it is becoming increasingly accepted that dietary factors play an important role. Although breast cancer can occur in either males or females, only about 1 % of all cases occur in men, and male breast cancer is a rare disease in all parts of the world." Although there appear to be some similar risk factors for breast cancer in males and females, there is no indication in the literature that diet is either a risk or a protective factor for male breast cancer. The development of breast cancer is known to be highly dependent on the hormones associated with female reproductive functions, while established genetic factors have been... 

Breast cancer is cancer of the breast tissues. The major part of this cancer in women is dependent on the female sex hormones for their growth. An estrogen antagonist can therefore be used in the treatment of breast cancer to limit the growth of the tumor. 

Although clinical deficiency disease is rare, there is evidence that a significant proportion of the population have marginal vitamin Bg status. Moderate deficiency results in abnormalities of tryptophan and methionine metabolism. Increased sensitivity to steroid hormone action may be important in the development of hormone-dependent cancer of the breast, uterus, and prostate, and vitamin Bg status may affect the prognosis. 

Breast cancer is one of the most common forms of cancer affecting women and, in Western countries, the incidence is rising. The risk of breast cancer increases markedly with age, although a decrease in the rate occurs after the menopause, suggesting that development is hormone-dependent. To date, a number of hormone-related risk factors have been identified (Bingham et al, 1998). Countries such as Japan have relatively low rates of breast cancer, which have been associated with consumption of a diet high in soy foods. Currently, however, the data from epidemiological studies is inconclusive. 

In order to get recent advances on the effects of phytoestrogens on hormonal-dependent diseases as well as on human supplementation trials, it might be useful to refer to http //www.venus-ca.org/ (EU-funded project on dietary exposure to phytoestrogens and related compounds and effects on skeletal tissues) http //www.phytos.org (EU-funded project on the prevention of osteoporosis by nutritional phytoestrogens) http //www.phytoprevent.org (EU-funded project on the role of phytoestrogens in the prevention of breast and prostate cancer) and http //www.nutrition.tum.de/isoheart.htm (EU-funded project on cardiovascular health of postmenopausal women). 

Cytotoxic chemotherapy is eventually required in most patients with metastatic breast cancer. Patients with hormone-receptor-negative tumors require chemotherapy as initial therapy of symptomatic metastases. Patients who respond initially to hormonal manipulations eventually cease to respond and go on to require chemotherapy. The median duration of response is 5 to 12 months, but some patients will have an excellent response to an initial course of chemotherapy and may live 5 to 10 years or longer without evidence of disease. In general, median survival of patients after treatment with commonly used drug combinations for metastatic breast cancer is 14 to 33 months. The median time to response has ranged from 2 to 3 months in most studies, but this period depends in large part on the site of measurable disease. The median time to appearance of response is between 3 and 6 weeks in patients whose disease is primarily in the skin and lymph nodes, 6 to 9 weeks in patients with metastatic lung involvement, 15 weeks in patients with hepatic involvement, and nearly 18 weeks in patients with bone involvement. Thus it is often the case that an immediate response to therapy is not... 

Pasqualini JR, Chetrite G, Nguyen BL, Maoloche C, Delalonde M, Talbi M, Feinstein MC, Blacker C, Botella J and Paris J (1995) Estrone sulfate-sulfatase and 17/3-hidroxis teroid dehydrogenase activities a hypothesis for their role in the evolution of human breast cancer from hormone-dependence to hormone-independence. J Steroid Biochem Mol Biol 53 407... 

The SERMs that belong to the benzopyrans group form a large group of drugs (Fig. 2.5), several of which are at early stages of clinical development for the treatment of hormone-dependent breast cancer and endometrial cancer. 

EM-800 (SCH-57050) and its active metabolite EM-652 (acolbifene, SCH-57068), are highly potent antiestrogens in human breast and uterine cancer cells in vitro as well as in vivo in nude mice and are currently undergoing clinical trials in the treatment of hormone-dependent breast cancer and endometrial cancer (Labrie et al 1999). Acolbifene shows a higher capacity of binding to... 

Veronesi U, Maisonneuve P, Rotmenz N et al. (2002b) Italian randomised trial among women with hysterectomy tamoxifen and hormone dependent breast cancer in high-risk women. J Natl Cancer Inst 94 160-165... 

The increasing clinical importance of tamoxifen in the 1980s prompted development of drugs that indirectly target the estrogen receptor, for example the aromatase inhibitor anastrozole (ARIMIDEX ), a selective inhibitor of estrogen biosynthesis [28]. Progress in treatment of hormone-dependent prostate cancer followed advances in breast cancer, with demonstration that... 

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