We present data showing that some foods preserved in lacquer-coated cans and the liquid in them may acquire estrogenic activity. Hormonal activity was measured using the E-screen bioassay. The biological activity of vegetables packed in cans was a result of plastic monomers used in manufacturing the containers. The plastic monomer bisphenol-A, identified by mass spectrometry, was found as a contaminant not only in the liquid of the preserved vegetables but also in water autoclaved in the cans. The amount of bisphenol-A in the extracts accounted for all the hormonal activity measured. Although the presence of other xenoestrogens cannot be ruled out, it is apparent that all estrogenic activity in these cans was due to bisphenol-A leached from the lacquer coating. The use of plastic in food-packaging materials may require closer scrutiny to determine whether epoxy resins and polycarbonates contribute to human exposure to xenoestrogens.ImagesFigure 1.Figure 2. AFigure 2. BFigure 3. AFigure 3. BFigure 4.Figure 5. AFigure 5. BFigure 6.
We found an increased risk for breast cancer in the leaner women, especially in the leaner postmenopausal subgroup, related to the TEXB-alpha. The pesticides aldrin and lindane are also individually associated with risk.
The chemical structure of hydroxylated diphenylalkanes or bisphenols consists of two phenolic rings joined together through a bridging carbon. This class of endocrine disruptors that mimic estrogens is widely used in industry, particularly in plastics. Bisphenol F, bisphenol A, fluorine-containing bisphenol A (bisphenol AF), and other diphenylalkanes were found to be estrogenic in a bioassay with MCF7 human breast cancer cells in culture (E-SCREEN assay). Bisphenols promoted cell proliferation and increased the synthesis and secretion of cell type-specific proteins. When ranked by proliferative potency, the longer the alkyl substituent at the bridging carbon, the lower the concentration needed for maximal cell yield; the most active compound contained two propyl chains at the bridging carbon. Bisphenols with two hydroxyl groups in the para position and an angular configuration are suitable for appropriate hydrogen bonding to the acceptor site of the estrogen receptor. Our data suggest that estrogenicity is influenced not only by the length of the substituents at the bridging carbon but also by their nature. Because diphenylalkane derivatives are widespread and their production and use are increasing, potential exposure of humans to estrogenic bisphenols is becoming a significant issue. The hazardous effects of inadvertent exposure to bisphenol-releasing chemicals in professional workers and the general populations therefore deserve investigation.ImagesFigure 1Figure 2Figure 3Figure 4
Reporting of the outcome of radiotherapy is not satisfactory without a description of the treatment-related side effects. The purposes of this paper were: (1) to evaluate the frequency and the severity of collateral skin reactions in a group of breast cancer patients; (2) to report the acute reactions using some current scoring systems and to compare the application of them, and (3) to investigate the variation between intra- and interobservers using these different scales. We studied 108 breast cancer patients who, after surgical treatment, received adjuvant radiotherapy. Clinical skin evaluation was always performed by the same radiotherapist the last day of treatment, and the collateral radiation effects were photographed at that moment to facilitate later evaluations by another two expert doctors. Normal tissue damage was scored according to the Radiation Therapy Oncology Group/The European Organisation for Research, and Treatment of Cancer/ (RTOG/EORTC), the Danish, the European, and the Biomed2 side-effect scales. The most frequent acute complications found were erythema (91.7%), dry desquamation (29.6%) and moist desquamation (35.2%). The reactions were classified as severe in 13.9, 23, 18.5 and 13% of the patients with each of the different systems used, respectively. The concordance between the scoring of radiation-induced side effects on the skin assessed by direct observation of the patients or by examination of the photographic document was sufficient. This is a warrant of accuracy in the evaluation of acute normal tissue lesions. Our results allow us to state the advantage of the RTOG system over the others in terms of evaluating the acute effects produced by radiotherapy of women with breast cancer.
The aim of the present study was to investigate the association between gene hypermethylation and main clinicopathological features of breast cancer, including diagnosis and treatment response. A sensitive SYBR green methylation-specific PCR technique was used to analyze the utility of circulating DNA with CpG island hypermethylation of ESR1, APC, RARB, 14-3-3-sigma and E-cad gene promoter regions as breast cancer biomarkers. Analyses were conducted of preoperative sera from 106 women with breast cancer, 34 with benign breast disease and 74 with no evidence of breast disease and of post-treatment sera from 60 of the breast cancer patients. Mean serum values of methylated ESR1 and 14-3-3-sigma gene promoters significantly differed between breast cancer patients and healthy controls (p = 0.0112 for ESR1 and p = 0.0047 for 14-3-3-sigma). When their results were combined, it was found that hypermethylation of these two genes differentiated between breast cancer patients and healthy controls (p < 0.0001) with a sensitivity of 81% (95% confidence interval: 72-88%) and specificity of 88% (95% CI: 78-94%). Presence of methylated ESR1 in serum of breast cancer patients was associated with the ER negative phenotype (p = 0.0179). Serum hypermethylation at ESR1 and 14-3-3-sigma loci was observed in cancer patients, in situ carcinoma and benign breast disease. No significant differences in methylated ERS1 or 14-3-3-sigma values were observed between pre-surgery and post-treatment measurements. Preliminary clinical applications of this approach have revealed several shortcomings, including a frequent presence of methylated 14-3-3-sigma in sera from women with breast benign disease. These findings cast some doubts on the utility for early cancer diagnosis of highly sensitive techniques to identify hypermethylation of specific gene promoters in DNA extracted from serum. Although numerous issues remain to be resolved, the quantitative measurement of circulating methylated DNA remains a promising tool for cancer risk assessment.
For routine maintenance, cells were grown in Dulbecco's modification of Eagle's medium (DME) supplemented with 5% fetal bovine serum (FBS; PAA Labor und Forschungs Ges, MBH, Linz, Austria) in an atmosphere of 5% C02/95% air under saturating humidity at 37°C, except for MCF7 cells BB104, which were routinely maintained in 10% charcoal dextran-treated human serum (CDHS)-supplemented phenol red-free DME medium, prepared as described below.Plasma-derived human serum was prepared from expired plasma by adding calcium chloride to a final concentration of 30 mM to facilitate clot formation. Sex steroids were removed from serum by charcoal-dextran stripping (6).Cellproliferation experiments. We used MCF7 cells in the E-screen test according to a technique slightly modified from that originally described by Soto et al. (5). Briefly, cells were trypsinized and plated in 24-well plates (Limbro, McLean, Virginia) at an initial concentration of 10,000 cells per well in 5% FBS in DME. BB104 cells were seeded in 10% CDHS supplemented medium. The cells were allowed to attach for 24 hr, then 10% CDHS-supplemented phenol red-free DME was substituted for the seeding medium. A range of concentrations of the test compound were added, and the assay was stopped after 144 hr by removing the medium from wells, fixing the cells, and staining them with sulforhodamine-B (SRB).The fixation and staining technique was modified from that described by Skehan et al. (9). Briefly, cells were treated with cold 10% trichloracetic acid and incubated at 4°C for 30 min. Then the cells were washed five times with tap water and left to dry. The fixed cells were stained for 10 min with
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