Women's experiences of risk-stratified breast cancer screening in the MyPeBS trial: a qualitative comparative study across two European countries.

OBJECTIVE: Risk-stratification should improve the benefits-to-harms ratio for breast screening, whereby higher-risk women receive additional screening and low-risk women are screened less. This study investigated the effects of healthcare context by comparing how women in England and France experienced risk-based breast screening. METHODS AND MEASURES: Fifty-two women were purposively sampled from participants who underwent risk-based screening in the MyPeBS trial. Women received objectively-derived 5-year breast cancer risk estimates (low = < 1%, average = 1-1.66%, high = ≥ 1.67 to <6%, very-high-risk = ≥ 6%). This determined future trial-related screening schedules and prevention options. Semi-structured interviews were transcribed for thematic framework analysis. RESULTS: Two overarching themes were produced: the importance of supported risk communication and accessibility of risk management. Overall, risk-based breast screening was viewed positively. However, trial procedures, especially in risk estimate provision, differed across sites. Women at increased risk were more reassured when appointments were with specialist healthcare professionals (HCP). When absent, this resulted in reduced satisfaction with risk communication and greater uncertainty about its personal relevance. Low-risk women's views on extended mammogram schedules seemed linked to how health services are organised differently. CONCLUSIONS: Context is an important consideration regarding acceptability of healthcare innovations such as risk-stratified screening: it should not be assumed that findings from one country apply universally.

Phytoestrogen-rich diets modulate expression of Brca1 and Brca2 tumor suppressor genes in mammary glands of female Wistar rats.

Phytoestrogens are natural compounds with anticancer, proliferation, differentiation, and chemopreventive effects, for which several mechanisms have been proposed. In the present study, modulation of Brca1 and Brca2 expression by different phytoestrogen-rich diets has been investigated in ovariectomized Wistar rats. Two hundred mammary glands were harvested in three independent experiments. Brca1 and Brca2 mRNAs were quantified by real-time quantitative reverse transcription-PCR, and their proteins by immunohistochemistry. The first experiment compared the influence of different phytoestrogens [flax-seed, isoflavones (IFs), or rutin]. A 10% increase in Brca1 mRNA expression was shown after flax-seed consumption, whereas no variation was noted for Brca2 mRNA, nor for Brca1 and Brca2 proteins. In the second experiment, two soy IFs sources (Novasoy or Soylife) were given at different concentrations to the animals. Only Brca2 mRNA was increased and only at high doses. Finally, the effect of IFs was compared with that of estradiol. An increase in mRNA for both genes was noted after estradiol treatment and with the highest dose of IFs. In conclusion, our results show that IFs, given in the diet at different doses, are able to increase Brca1 and Brca2 mRNA in ovariectomized female Wistar rat. However, no variation in Brca1 or Brca2 protein expression was demonstrated, whatever the experimental conditions were.

Expression of BRCA1 and BRCA2 in male breast cancers and gynecomastias.

BRCA1 and BRCA2 breast cancer susceptibility genes are responsible for most of the hereditary breast cancers. Mutations in BRCA1 account for up to 40-50% of families with hereditary breast cancer only. Mutations in BRCA2 are linked to the other half of inherited breast cancer families and also to male breast cancer. On the contrary, no sporadic breast tumors have been shown to harbor mutations in BRCA1 and BRCA2 genes. It seems that altered expressions of BRCA1 and BRCA2 genes may contribute to breast cancer development. Moreover, BRCA1 and BRCA2 expressions are regulated in human breast cancer cell lines by estrogen. We addressed the issue of BRCA1 and BRCA2 expression in male breast cancers and gynecomastias. We investigated the presence of BRCA1 and BRCA2 proteins in male breast specimens by immunohistochemical analysis with a panel of antibodies elicited against BRCA1 and BRCA2. The specificity of each antibody has been verified by Western blotting in cell lines from different origins. The characterization of 6 anti-BRCA1 antibodies revealed a BRCA1 200-kDa protein detected in breast cell lines (MDA-MB 231, HBL 100, T-47D and MCF7) or in an acute leukemia (MOLT 4), known to overexpress BRCA1. All 5 anti-BRCA2 antibodies detected a BRCA2 384-kDa protein in the HBL100 and MCF7 breast cell lines. By immunohistochemistry, we found nuclear, perinuclear, endoplasmic reticulum, Golgi vesicle, secretion and apical cytoplasmic stainings in gynecomastias and sporadic and hereditary male breast cancers, for BRCA1 and BRCA2 protein expressions. We report an extensive expression of BRCA1 and BRCA2 proteins in different compartments of the mammary gland cells in male breast carcinomas and gynecomastias. This is consistent with the estrogen-dependent expression of BRCA1 and BRCA2 in human breast cells.

Differential expressions of BRCA1 and BRCA2 in infantile gynecomastia.

BRCA1 and BRCA2 breast cancer susceptibility genes are responsible for most of the hereditary breast cancers. No or very few sporadic breast tumors have been shown to harbor mutations in the coding sequence of BRCA1 or BRCA2. In contrast to normal breast epithelial cells, BRCA1 mRNA levels in tumors appeared to be down-regulated by methylation, while BRCA2 showed significant overexpression in sporadic breast cancers. We report herein an infantile gynecomastia in a two-year-old boy, studied by immunohistochemistry of anti-BRCA1 and anti-BRCA2 antibodies. We demonstrated that BRCA1 proteins, like BRCA2, are widely expressed in the nuclei of epithelial cells surrounding the lumen of the ducts in infantile gynecomastia. The intensive nuclear staining of both proteins in the mammary tissues means that BRCA1 and BRCA2 proteins are largely expressed in infantile gynecomastia.

Effects of the phytoestrogens genistein and daidzein on BRCA2 tumor suppressor gene expression in breast cell lines.

A high intake of isoflavones is associated with a reduction of breast cancer among Japanese women. The aim of this study was to quantify BRCA2 tumor suppressor gene expression after treatment of cells with the phytoestrogens daidzein and genistein, the main compounds of soy. The effects of 5 microg/ml genistein and 20 microg/ml daidzein on BRCA2 expression were studied in two human mammary tumor cell lines, MCF7 and MDA-MB-231, and one normal human breast epithelial cell line, MCF10a. BRCA2 mRNA was evaluated by quantitative real time RT-PCR and the amount of BRCA2 protein was measured by affinity chromatography. With Genistein, we observed a 60% increase of BRCA2 mRNA in MDA-MB-231 and MCF10a, which are, respectively, estrogen receptors alpha-/beta+ and alpha-/beta-, and no variation in MCF7, which is ERalpha+/beta+. Dairzein had no effect on BRCA2 mRNA expression. The level of BRCA2 protein with both food components also remained unchanged in all three cell lines. This suggests regulation of BRCA2 between the mRNA and protein levels. Treatment with actinomycin D and cycloheximide demonstrated that the increase in BRCA2 mRNA was not blocked by cycloheximide, indicating that de novo protein synthesis was required in MDA-MB-23, although de novo synthesis was not required in MCF10a for the genistein. With actinomycin D, genistein had a positive effect on the transcriptional level of BRCA2 mRNA in MDA-MB-231 and MCF10a. The use of an anti-estrogen suggested that the action of daidzein and genistein might not be mediated through the ER.

Differential effects of n-3 and n-6 polyunsaturated fatty acids on BRCA1 and BRCA2 gene expression in breast cell lines.

Current evidence strongly supports a role for the breast tumour suppressor genes, BRCA1 and BRCA2, in both normal development and carcinogenesis. In vitro observations reported that BRCA1 and BRCA2 are expressed in a cell cycle-dependent manner. Interestingly, differences in the actions of n-3 and n-6 polyunsaturated fatty acids have been observed: while the n-3 polyunsaturated fatty acids have been described to reduce pathological cell growth, the n-6 polyunsaturated fatty acids have been found to induce tumour proliferation. Here, we examined the expression of BRCA1 and BRCA2 in breast cell lines after treatment with polyunsaturated fatty acids. Real-time quantitative polymerase chain reaction determinations conclusively demonstrated increases in BRCA1 and BRCA2 mRNA expressions in MCF7 and MDA-MB 231 tumour cell lines after treatment with n-3 polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid), but no variation was noticed with the n-6 polyunsaturated fatty acid (arachidonic acid). On the other hand, no variation of the expression of BRCA1 and BRCA2 mRNA was detected in MCF10a normal breast cell line treated by polyunsaturated fatty acids. The level of BRCA1 and BRCA2 proteins quantified by affinity chromatography remained unchanged in tumour (MCF7, MDA-MB 231) and normal (MCF10a) breast cell lines. We suggest the presence of a possible transcriptional or post-transcriptional regulation of BRCA1 and BRCA2 after n-3 polyunsaturated fatty acid treatment in breast tumour cells.