The Breast Cancer Prevention Trial: evaluating tamoxifen's efficacy in preventing breast cancer

Effects of neoadjuvant therapies on genetic regulation of targeted pathways in ER+ primary ductal breast carcinoma: A meta-analysis of microarray datasets

Breast cancer arises as a result of multiple interactions between environmental and genetic factors. Conventionally, breast cancer is treated based on histopathological and clinical features. DNA technologies like the human genome microarray are now partially integrated into clinical practice and are used for developing new "personalized medicines" and "pharmacogenetics" for improving the efficiency and safety of cancer medications. We investigated the effects of four established therapies-for ER+ ductal breast cancer-on the differential gene expression. The therapies included single agent tamoxifen, two-agent docetaxel and capecitabine, or combined three-agents CAF (cyclophosphamide, doxorubicin, and fluorouracil) and CMF (cyclophosphamide, methotrexate, and fluorouracil). Genevestigator 8.1.0 was used to compare five datasets from patients with infiltrating ductal carcinoma, untreated or treated with selected drugs, to those from the healthy control. We identified 74 differentially expressed genes involved in three pathways, i.e., apoptosis (extrinsic and intrinsic), oxidative signaling, and PI3K/Akt signaling. The treatments affected the expression of apoptotic genes (TNFRSF10B [TRAIL], FAS, CASP3/6/7/8, PMAIP1 [NOXA], BNIP3L, BNIP3, BCL2A1, and BCL2), the oxidative stress-related genes (NOX4, XDH, MAOA, GSR, GPX3, and SOD3), and the PI3K/Akt pathway gene (ERBB2 [HER2]). Breast cancer treatments are complex with varying drug responses and efficacy among patients. This necessitates identifying novel biomarkers for predicting the drug response, using available data and new technologies. GSR, NOX4, CASP3, and ERBB2 are potential biomarkers for predicting the treatment response in primary ER+ ductal breast carcinoma.

The role of community advisory boards: involving communities in the informed consent process

Ethical research involving human subjects mandates that individual informed consent be obtained from research participants or from surrogates when participants are not able to consent for themselves. The existing requirements for informed consent assume that all study participants have personal autonomy; fully comprehend the purpose, risks, and benefits of the research; and volunteer for projects that disclose all relevant information. Yet contemporary examples of lapses in the individual informed consent process have been reported. The authors propose the use of community advisory boards, which can facilitate research by providing advice about the informed consent process and the design and implementation of research protocols. These activities could help reduce the number of individual informed consent lapses, benefiting study participants and the scientific integrity of the research in question.

Indole-3-carbinol is a negative regulator of estrogen receptor-alpha signaling in human tumor cells

Estrogen, via its binding to the estrogen receptor (ER), plays an important role in breast cancer cell proliferation and tumor development. Indole-3-carbinol (I3C), a compound occurring naturally in cruciferous vegetables, exhibits a potent antitumor activity via its regulation of estrogen activity and metabolism. This study was designed to determine the effect of I3C on the potential to inhibit the ER-alpha. Using a reporter gene driven by the estrogen receptor, I3C (10-125 micromol/L) significantly repressed the 17ss-estradiol (E2)-activated ER-alpha signaling in a dose-dependent manner. I3C and breast cancer susceptibility gene 1 (BRCA1) synergistically inhibited transcriptional activity of ER-alpha. Moreover, I3C down-regulated the expression of the estrogen-responsive genes, pS2 and cathepsin-D, and up-regulated BRCA1. The inhibitory effects of I3C did not contribute to its cytotoxic effects because these activities were observed at less than toxic concentrations. These results further suggest that antitumor activities of I3C are associated not only with its regulation of estrogen activity and metabolism, but also its modulation of ER transcription activity.

Diphenyl quinolines and isoquinolines: synthesis and primary biological evaluation

The synthesis of a series of 35 substituted 3,4-diphenyl quinolines and isoquinolines is described. The majority of these molecules differ from all other triphenylethylene based antiestrogens by a different spatial location of the aminoalkyl side chain. The binding affinity of the most representative molecules (8, 9, 19, 20, 21, 23 and 25), including analogues 8 and 21 without the side chain, for the estrogen receptor alpha (ER) was determined. The ability of these molecules to induce the progesterone receptor was also studied. Antiproliferative activity was evaluated on MCF-7 human breast cancer cells, while intrinsic cytotoxic/cytostatic properties resulting from interaction with other targets than ER were assayed on L1210 murine leukemia cells. Introduction of an aminoalkylamino side chain at carbon 2 confers strong cytotoxic properties to diphenylquinolines 9 and 10 as well as pure antiestrogenic activities. However, cytotoxicity is so high with respect to antiestrogenicity that the latter was clearly observable only in one case (9b). The structure of compound 9b was determined by X-ray crystallography. Molecular modeling of its docking within the hormone-binding domain of the receptor was subsequently undertaken. According to our results, the design of molecules with the side chain bound to the ethylene part of the triphenyl ethylene skeleton might generate compounds of potential pharmacological interest.

Factors implicated in the decision whether or not to join the tamoxifen trial in women at high familial risk of breast cancer

Why, given similar medical circumstances-high familial risk of breast cancer-will some women elect to join a trial of drugs designed to reduce that risk but others choose not to take part? The aim of this study was to identify measurable differences between women who elect to join a placebo-controlled, double-blind randomised trial of the drug tamoxifen and women who elect not to join. One hundred and six women attending a breast care clinic completed questionnaires covering demographic details, health locus of control, perception of risk and adequacy of medical communication. All were eligible for inclusion in the tamoxifen trial. Only half (n=53) of the sample elected to join, the other half (n=53) declined. Those who declined the trial were significantly more aware of lifestyle factors thought to influence the development of cancers-diet, exercise and oestrogen-prolonging activities (p<0.001), and they also appeared to find the information given by the hospital about tamoxifen harder to understand than did the group who had joined the trial (p=0.01). They could think of significantly fewer positive reasons for joining (p<0.001) and were significantly younger (p=0.001). Participants in both groups significantly overestimated the relative risks of breast cancer. The average estimation of risk for women aged 30 with a family history of breast cancer was 22 times higher than that given by their consultant. This gives rise to considerable concerns about the information underpinning informed consent.

Possible respect of patient quality of life--without reducing survival expectancy--in breast cancer treatment

The treatment of breast cancer by some doctors in all countries and all in some does not concern itself with quality of life considerations. Partial breast cancer surgery is possible in cases of neither voluminous nor central tumors, and surgery can also be partial after pre-surgical chemotherapy reduction. The apoptotic test for cytostatic choice should assist in obviating toxicities which are minor for the physician, i.e., alopecia, cardiac lesion, etc, but which are major for the patient. Cytostatics will be useless in treatment if they are not apoptogenic. Hormonal treatment may, when there are estrogen receptors involved, be advantageously combined with chemotherapy. In estrogen receptors absence, growth factor receptors should be considered, as there is a possible indication of somatostatin analogs (instead of hormones, which are useless). Quality of life is mainly determined by the partial character of the surgery, hence by the volume and localization of the tumor. Cancer screening allows diagnosis when tumors are smaller as opposed to those which are the object of spontaneous diagnosis. We even propose screening of dysplasias and their biological treatment between 40 and 50 years--hormonal if the specific cells carry hormone receptors, and based on somatostatin analogs if they carry growth factor receptors.