Cancers breast

A study of the relationship between dietary factors and breast tumor characteristics was carried out in premenopausal women (Touillaud et al., 2005). Tumors were characterized in terms of their estrogen receptor (ER) status. Tumors with ER-positive status, as compared to ER-negative, are known to respond to the proliferative effect of estrogen, and are more likely to react to endocrine therapy. In the study, a low intake of boron (0.8 mg/day) was associated with a lower risk of ER-negative tumors as compared to a higher intake (1.03 mg/day). A similar relationship was observed with phytochemicals, such as phytosterols and kaempferol. Although these data are preliminary, they suggest that the effect of boron is confounded by the presence of phytosterols that are known to interfere with the entero-hepatic circulation of steroids, steroid hormones, and cholesterol (Samman et al, 2004). 

There is an extensive literature on the association between fat intake and the risk of breast cancer. Many animal studies showed that diets high in fat are associated with an increased incidence of chemically induced tumor development. However, these associations may be due to the effect of total energy intake. The study of Ip et al. (1990), designed specifically to determine the effect of fat, independent of energy intake, showed that  

High intake of total fat is correlated with an increased incidence of breast cancer in international comparative studies. In addition to the usual factors that confound associations between dietary fat and cancer in this type of study, countries with a high fat intake also have a lower age at menarche, later age at first birth, lower parity and higher post-menopausal body weight, which are risk factors for breast cancer (Willett, 2001b Kushi and Giovannucci, 2002). 

The 14-year follow-up of the Nurses Health Study, the largest of the prospective studies with 2,956 cases, also found no evidence of association between total or type of fat and breast cancer risk (Holmes et al., 1999a). Further, no survival advantage was found for a low-fat diet or diets containing a particular fat type after diagnosis of breast cancer in this cohort of nurses (Holmes et al., 1999b). 

Opposing effects of certain individual fatty acids could have influenced the lack of a relationship between dietary fat and fat type with the risk of breast cancer. Well-conducted animal studies suggest that linoleic acid promotes development of mammary tumors, whereas saturated, monounsatu-rated, and trans fatty acids have little or no effect. In many cases, w-3 polyunsaturated fatty acids suppress tumor development. Conjugated linoleic acid (CLA) is the most potent anti-cancer fatty acid in that amounts of 1% or less of dietary fat can substantially inhibit the development of mammary tumors (Ip, 1997). 

Nevertheless, at this time there is no persuasive evidence from epidemiological studies that any individual fatty acid is associated with the risk of breast cancer (Willett, 1997). A pooled analysis of nine prospective studies showed no association between the intake of various dairy products and the risk of breast cancer (Missmer et al., 2002). However, in epidemiological studies there is often a high degree of correlation between individual fatty acids in the diet. This reduces the ability to detect an independent association between a single acid and cancer risk. Furthermore, dietary assessment during an epidemiological study may not reflect an individual s diet at the time of cancer initiation, which in the case of breast cancer may be in early life. 

Tamoxifen (Novaldex) entered a clinical trial at the Christie Hospital in Manchester in 1971 and rapidly became the treatment of choice for post-menopausal patients with breast cancer. Not surprisingly, response rates are typically twice as good for patients with tumours that have oestrogen 

Although it is too early to tell whether the aromatase inhibitors like anastrozole and letrozole will eventually replace the anti-oestrogens like 

The principles and potential clinical applications of SELDI-TOF-MS and microarray techniques have been reviewed with respect to screening, diagnosis, prediction of aggressiveness, response to treatment, and toxicity [75]. 

In a study aiming to establish quality control for NAF analysis, rigidly controlled experimental conditions were repeated 36 times. Algorithms were developed for the quantification of 700 analyte peaks (—18,000 time points) at low masses [81]. 

A comparative study of tissues (obtained using LCM) from primary breast cancer with and without axillary lymph node metastasis was carried out with SELDI-TOF-MS and analyzed using ANOVA and multivariate logistic regression. 

Two metal-binding polypeptides (4871 and 8596 Da) were identified as significant risk factors [82], 

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C. It is a cytotoxic agent used in the treatment of neoplastic disease, e.g. breast cancer. 

Fluorouracil is one component of a mixture of three drugs used in breast cancer chemotherapy What is its stmcture" ... 

Many human diseases are caused when certain proteins are either over- or underexpressed. Eor example, breast cancer can be induced by overexpressing certain cellular oncogenes within mammary tissue. To study the disease, researchers produce a line of transgenic mice that synthesize an abnormal amount of the same protein. This leads to symptoms of the disease in mice that are similar to what is found in humans. A protein can be overexpressed by inserting a DNA constmct with a strong promotor. Conversely, underexpression of a protein can be achieved by inserting a DNA constmct that makes antisense RNA. This latter blocks protein synthesis because the antisense RNA binds and inactivates the sense mRNA that codes for the protein. Once a line of mice is developed, treatments are studied in mice before these therapies are appHed to humans. 

Meg estrolAceta.te. This compound is used outside the United States as an oral contraceptive. In the United States, it is used for the paUiative treatment of breast cancer and endometrial cancer, or as an adjunct to other therapies. Its use has been associated with an increased appetite and food intake and has been evaluated in the treatment of anorexia and cachexia (107). 

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... 

For the purposes of this article, antiestrogens are compounds that counteract the biological activity of estrogens at the receptor level. In the late 1970s, there were no steroidal antiestrogens in widespread clinical use. Clomiphene [911 -45-5]( ) and tamoxifen/7(954(9-25 -/7(9) were nonsteroidal antiestrogens that had been employed for the treatment of female infertility and breast cancer, respectively. 

WS-7528 [132147-69-4][VI] a nonsteroidal estrogen, is an isoflavone which has been isolated from Streptomjces sp. No. 7528 and is an estrogen agonist. It inhibits [3ff]-estradiol binding to its receptor in rat uterine cytosol at an inhibitor for 50% of the rats tested (IC q) concentration of 5.7 nM. It also induces the growth of estrogen-dependent human breast cancer cell line MCE-7 (7). 

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... 

R)-3-Eth5i-3(4-pyridyl)piperidine-2,6-dione (197), useful in the treatment of certain breast cancers, is a 20-fold more potent aromatase inhibitor... 

Another example is the use of Tc-sestamibi, approved for use in the evaluation of coronary artery disease and myocardial infarction, in patients with breast cancer. Use in breast cancer is under investigation by a number of physicians. The data are not yet sufficient to determine the efficacy of this agent in this setting. Its safety, of course, has already been demonstrated as part of its initial evaluation for heart disease. 

Whereas epidermal growth factor (EGF) enhances the radiosensitivity of human squamous ceU carcinoma cells in vitro (197), addition of EGF to hormone-deprived MCE-7 breast cancer cells prior to irradiation results ia iacreased radioresistance (198). An anti-EGE-receptor monoclonal antibody blocks the abiUty of EGE to enhance growth and radioresistance. Tumor cells, the growth of which is stimulated by EGE, appear to be protected those where growth is iohibited are sensitized (198). 

USP (Megace) testolactone USP [968-93 ] C19H24O3 300.40 (61) or endrome-trium breast cancer hyper-calcemia common side effects of steroids fluid retention ... 

Lentaron) gosetelin USP [65807-02-5] C59Hg4NigOi4 1269.43 (63) postmenopausal breast cancer prostatic carcinoma bone pain common... 

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