Detection of estrogen receptor in formalin-fixed and paraffin-embedded breast carcinoma: correlation with histological patterns.

The authors studied the expression of estrogen receptor (ER) in tissues of breast carcinomas which were previously fixed in formalin and paraffin-embedded. The ER expression was correlated with several histological findings, namely grade of differentiation, tumor necrosis, desmoplasia, lymphocytic infiltration and elastosis. The ER was detected in tissues using the avidin-biotin immunoperoxidase technique associated with the H222 monoclonal antibody from Abbott. All 39 biopsies were of infiltrating ductal carcinoma of breast and 16 of them expressed ER. The statistical analysis showed that the expression of ER was correlated with histological findings of good prognosis as well differentiated carcinomas, no tumor necrosis, absence or mild lymphocytic infiltration around the tumor cells and severe elastosis.

Acellular dermal tissue study: an ultrastructural evaluation of human and porcine derived tissues in a rat model

The purpose of this study was to evaluate the host response of a human and a porcine derived acellular dermal tissue (ADT) implanted in the subcutaneous tissue of a rat model. Two subcutaneous pockets were surgically created along the dorsal midline of 25 rats (5 rats/group). The human ADT was placed superiorly and the porcine ADT, inferiorly. The animals were sacrificed at 07, 15, 30, 60 and 180 postoperative days (PO) and the ADTs and surrounding soft tissues were assessed for ultrastructural evaluation by transmission electron microscopy. The ultrastructural findings were similar in both materials. Normal collagen and elastic fibers bundles were observed during all experimental moments, as well as macrophages presenting cytoplasmic enlargements digesting cellular portions after 15 PO. From 30 until 180 PO, vacuolar structures filled with an amorphous, electron-transparent substance, were present inside and outside the fibroblasts. Both human and porcine ADT showed similar pattern of ultrastructural response when implanted in the subcutaneous tissue of rats. The porcine ADT appears as a good alternative to be used as a biomaterial.

A comparison of human and porcine acellular dermal tissues in the subcutaneous space of a rat model

The study compared the host response to a human and a porcine acellular dermal tissue implanted in the subcutaneous space of a rat model. The human and porcine acellular grafts were surgically implanted in the subcutaneous tissue of rats (5 rats/group) and the materials were evaluated at 7, 15, 30, 60 and 180 postoperative days (PO). The histological immune response was quantified using a digital image analysis system, which evaluated the number of vessels present in the implants and in the surrounding soft tissue, the area of inflammatory cell infiltration in the grafts, the width of the capsular formation present around the tissues and the area of implants absorbed. The data were submitted to statistical analysis. Light microscopy showed mononuclear cellular infiltration, the presence of a capsular formation surrounding the grafts and the presence of vacuolar structures (optically empty spaces) inside the implants. The image analysis comparing both materials showed significant inflammatory cells in the human graft at 15 and 30 PO, thicker capsular formation in the porcine tissue at 60 PO, increased number of vessels inside the implants and in the surrounding tissues in the porcine graft and a similar absorption pattern in both materials at 180 PO. The histological findings showed that both tissues were well-tolerated when implanted in the subcutaneous tissue of rats, allowing us to consider the porcine acellular dermal graft as a provisional alternative material for reconstructive plastic surgery. Copyright © 2005 Taylor & Francis LLC.

Genomic and phenotypic profiles of two Brazilian breast cancer cell lines derived from primary human tumors

Breast cancer is the most common type of cancer among women worldwide. Research using breast cancer cell lines derived from primary tumors may provide valuable additional knowledge regarding this type of cancer. Therefore, the aim of this study was to investigate the phenotypic profiles of MACL-1 and MGSO-3, the only Brazilian breast cancer cell lines available for comparative studies. We evaluated the presence of hormone receptors, proliferation, differentiation and stem cell markers, using immunohistochemical staining of the primary tumor, cultured cells and xenografts implanted in immunodeficient mice. We also investigated the ability of the cell lines to form colonies and copy number alterations by array comparative genomic hybridization. Histopathological analysis showed that the invasive primary tumor from which the MACL-1 cell line was derived, was a luminal A subtype carcinoma, while the ductal carcinoma in situ (DCIS) that gave rise to the MGSO-3 cell line was a HER2 subtype tumor, both showing different proliferation levels. The cell lines and the tumor xenografts in mice preserved their high proliferative potential, but did not maintain the expression of the other markers assessed. This shift in expression may be due to the selection of an 'establishment' phenotype in vitro. Whole-genome DNA evaluation showed a large amount of copy number alterations (CNAs) in the two cell lines. These findings render MACL-1 and MGSO-3 the first characterized Brazilian breast cancer cell lines to be potentially used for comparative research. © 2013 Spandidos Publications Ltd. All rights reserved.

Expression of Clock Genes in Human Subcutaneous and Visceral Adipose Tissues

Disrupted circadian rhythms are associated with obesity and metabolic alterations, but little is known about the participation of peripheral circadian clock machinery in these processes. The aim of the present study was to analyze RNA expression of clock genes in subcutaneous (SAT) and visceral (VAT) adipose tissues of male and female subjects in AM (morning) and PM (afternoon) periods, and its interactions with body mass index (BMI). Ninety-one subjects (41 +/- 11 yrs of age) presenting a wide range of BMI (21.4 to 48.6 kg/m(2)) were included. SAT and VAT biopsies were obtained from patients undergoing abdominal surgeries. Clock genes expressions were evaluated by qRT-PCR. The only clock gene that showed higher expression (p < .0001) in SAT in comparison to VAT was PER1 of female (372%) and male (326%) subjects. Different patterns of expression between the AM and PM periods were observed, in particular REV-ERBa, which was reduced (p < .05) at the PM period in SAT and VAT of both women and men (women: similar to 53% lower; men: similar to 78% lower), whereas CLOCK expression was not altered. Relationships between clock genes were different in SAT vs. VAT. BMI was negatively correlated with SATPER1 (r = -.549; p = .001) and SATPER2 (r = -.613; p = .0001) and positively with VATCLOCK (r = .541; p = .001) and VATBMAL1 (r = .468; p = .007) only in women. These data suggest that the circadian clock machinery of adipose tissue depots differs between female and male subjects, with a sex-specific effect observed for some genes. BMI correlated with clock genes, but at this moment it is not possible to establish the cause-effect relationship. (Author correspondence: mzanquetta@gmail.com)

Expression, localization, and functional model of cholesterol transporters in lactating and nonlactating mammary tissues of murine, bovine, and human origin

Members of the ATP-binding cassette (ABC) transporters play a pivotal role in cellular lipid efflux. To identify candidate cholesterol transporters implicated in lipid homeostasis and mammary gland (MG) physiology, we compared expression and localization of ABCA1, ABCG1, and ABCA7 and their regulatory genes in mammary tissues of different species during the pregnancy-lactation cycle. Murine and bovine mammary glands (MGs) were investigated during different functional stages. The abundance of mRNAs was determined by quantitative RT-PCR. Furthermore, transporter proteins were localized in murine, bovine, and human MGs by immunohistochemistry. In the murine MG, ABCA1 mRNA abundance was elevated during nonlactating compared with lactating stages, whereas ABCA7 and ABCA1 mRNA profiles were not altered. In the bovine MG, ABCA1, ABCG1, and ABCA7 mRNAs abundances were increased during nonlactating stages compared with lactation. Furthermore, associations between mRNA levels of transporters and their regulatory genes LXRalpha, PPARgamma, and SREBPs were found. ABCA1, ABCG1, and ABCA7 proteins were localized in glandular MG epithelial cells (MEC) during lactation, whereas during nonlactating stages, depending on species, the proteins showed distinct localization patterns in MEC and adipocytes. Our results demonstrate that ABCA1, ABCG1, and ABCA7 are differentially expressed between lactation and nonlactating stages and in association with regulatory genes. Combined expression and localization data suggest that the selected cholesterol transporters are universal MG transporters involved in transport and storage of cholesterol and in lipid homeostasis of MEC. Because of the species-specific expression patterns of transporters in mammary tissue, mechanisms of cholesterol homeostasis seem to be differentially regulated between species.

Expression and localization pattern of ABCA1 in diverse human placental primary cells and tissues

The ATP-binding cassette transporter A1 (ABCA1) mediates the transport of cholesterol, phospholipids, and other lipophilic molecules across cellular membranes. Recent data provide evidence that ABCA1 plays an important role in placental function but the exact cellular sites of ABCA1 action in the placenta remain controversial. To clarify this issue, we analyzed the cellular and subcellular localization of ABCA1 with immunocytochemistry, immunofluorescence and subsequent confocal or immunofluorescence microscopy in different types of isolated primary placenta cells: cytotrophoblast cells, amnion epithelial cells, villous macrophages (Hofbauer cells), and mesenchymal cells isolated from chorionic membrane and placental villi. After 12 h of cultivation, primary cytotrophoblast cells showed intensive membrane and cytoplasmic staining for ABCA1. After 24 h, with progressive syncytium formation, ABCA1 staining intensity was markedly reduced and ABCA1 was dispersed in the cytoplasm of the forming syncytial layer. In amnion epithelial cells, placental macrophages and mesenchymal cells, ABCA1 was predominantly localized at the cell membrane and cytoplasmic compartments partially corresponding to the endoplasmic reticulum. In these cell types, the ABCA1 staining intensity was not dependent on the cultivation time. In conclusion, ABCA1 shows marked expression levels in diverse placental cell types. The multitopic localization of ABCA1 in diverse human placental cells not all directly involved in materno-fetal exchange suggests that this protein may not only participate in transplacental lipid transport but could have additional regulatory functions.

Breast cancer and human papillomavirus (HPV) infection: No evidence of a viral etiology in a group of Swiss women

There are controversial data on the meaning of viral induction of breast cancer. The aim of this study was to investigate the presence of human papillomavirus (HPV) DNA in patients with breast carcinoma and the correlation of viral infection with disease outcome. Paraffin-embedded sections from 81 patients with breast cancer were analyzed for HPV DNA by polymerase chain reaction (PCR) using the SPF1/2 primers covering about 40 different low-, intermediate- and high-risk types. We found all samples were negative for HPV DNA. Our analysis could not support a role of HPV in breast carcinoma. Controversial published data indicate a need for further, larger epidemiologic studies.

Characterization of three human sec14p-like proteins: alpha-tocopherol transport activity and expression pattern in tissues

Three closely related human sec14p-like proteins (hTAP1, 2, and 3, or SEC14L2, 3, and 4, respectively) have been described. These proteins may participate in intracellular lipid transport (phospholipids, squalene, tocopherol analogues and derivatives) or influence regulatory lipid-dependent events. Here, we show that the three recombinant hTAP proteins associate with the Golgi apparatus and mitochondria, and enhance the in vitro transport of radioactively labeled alpha-tocopherol to mitochondria in the same order of magnitude as the human alpha-tocopherol transfer protein (alpha-TTP). hTAP1 and hTAP2 are expressed in several cell lines, whereas the expression level of hTAP3 is low. Expression of hTAP1 is induced in human umbilical cord blood-derived mast cells upon differentiation by interleukin 4. In tissues, the three hTAPs are detectable ubiquitously at low level; pronounced and localized expression is found for hTAP2 and hTAP3 in the perinuclear region in cerebellum, lung, liver and adrenal gland. hTAP3 is well expressed in the epithelial duct cells of several glands, in ovary in endothelial cells of small arteries as well as in granulosa and thecal cells, and in testis in Leydig cells. Thus, the three hTAPs may mediate lipid uptake, secretion, presentation, and sub-cellular localization in a tissue-specific manner, possibly using organelle- and enzyme-specific docking sites.

A novel enzyme immunoassay specific for ABCA1 protein quantification in human tissues and cells

ATP-binding cassette transporter A1 (ABCA1) mediates the transport of cholesterol and phospholipids from cells to lipid-poor HDL and maintains cellular lipid homeostasis. Impaired ABCA1 function plays a role in lipid disorders, cardiovascular disease, atherosclerosis, and metabolic disorders. Despite the clinical importance of ABCA1, no method is available for quantifying ABCA1 protein. We developed a sensitive indirect competitive ELISA for measuring ABCA1 protein in human tissues using a commercial ABCA1 peptide and a polyclonal anti-ABCA1 antibody. The ELISA has a detection limit of 8 ng/well (0.08 mg/l) with a working range of 9-1000 ng/well (0.09-10 mg/l). Intra- and interassay coefficient of variations (CVs) were 6.4% and 9.6%, respectively. Good linearity (r = 0.97-0.99) was recorded in serial dilutions of human arterial and placental crude membrane preparations, and fibroblast lysates. The ELISA measurements for ABCA1 quantification in reference arterial tissues corresponded well with immunoblot analysis. The assay performance and clinical utility was evaluated with arterial tissues obtained from 15 controls and 44 patients with atherosclerotic plaques. ABCA1 protein concentrations in tissue lysates were significantly lower in patients (n = 24) as compared with controls (n = 5; 9.37 +/- 0.82 vs. 17.03 +/- 4.25 microg/g tissue; P < 0.01). The novel ELISA enables the quantification of ABCA1 protein in human tissues and confirms previous semiquantitative immunoblot results.

Radiolabelled GLP-1 receptor antagonist binds to GLP-1 receptor-expressing human tissues.

PURPOSE Radiolabelled glucagon-like peptide 1 (GLP-1) receptor agonists have recently been shown to successfully image benign insulinomas in patients. For the somatostatin receptor targeting of tumours, however, it was recently reported that antagonist tracers were superior to agonist tracers. The present study therefore evaluated various forms of the (125)iodinated-Bolton-Hunter (BH)-exendin(9-39) antagonist tracer for the in vitro visualization of GLP-1 receptor-expressing tissues in rats and humans and compared it with the agonist tracer (125)I-GLP-1(7-36)amide. METHODS Receptor autoradiography studies with (125)I-GLP-1(7-36)amide agonist or (125)I-BH-exendin(9-39) antagonist radioligands were performed in human and rat tissues. RESULTS The antagonist (125)I-BH-exendin(9-39) labelled at lysine 19 identifies all human and rat GLP-1 target tissues and GLP-1 receptor-expressing tumours. Binding is of high affinity and is comparable in all tested tissues in its binding properties with the agonist tracer (125)I-GLP-1(7-36)amide. For comparison, (125)I-BH-exendin(9-39) with the BH labelled at lysine 4 did identify the GLP-1 receptor in rat tissues but not in human tissues. CONCLUSION The GLP-1 receptor antagonist exendin(9-39) labelled with (125)I-BH at lysine 19 is an excellent GLP-1 radioligand that identifies human and rat GLP-1 receptors in normal and tumoural tissues. It may therefore be the molecular basis to develop suitable GLP-1 receptor antagonist radioligands for in vivo imaging of GLP-1 receptor-expressing tissues in patients.

Polybrominated diphenyl ethers: Potential human exposure through household dust and dryer lint

This MPH thesis consists of (1) literature review of the relatively new synthetic persistent organic pollutants (POP), polybrominated diphenyl ethers (PBDEs), a type of flame retardant posing a potential public health hazard, (2) Presentation of data on PBDE levels in dryer lint from Dallas, TX and Hamburg, Germany. ^ PBDEs are used as additive fire retardants in plastics, polyurethane foam and electronic equipment to reduce flammability and thus save life and property. PBDEs have been widely used beginning in the 1970s. They resemble polychlorinated biphenyls (PCBs) in structure and toxicity. PBDEs are found in environmental sediments, sludges, and wildlife and even in human blood, milk and tissues. ^ PBDEs, due to their lipophilicity, accumulate in fat and other tissues and biomagnify up the food chain, with increasing concentrations. Animal studies have suggested potential health effects including thyroid disruption, permanent learning and memory impairment, fetal malformations, developmental neurotoxicity and, at high doses, possibly cancer. ^ PBDE levels are increasing in blood and breast milk in North America, but PBDEs intake unlike PCBs appears to be not primarily through food; food PBDE levels in the U.S. are not markedly higher than in Europe yet U.S. human blood and milk levels are much higher. For this reason various exposure pathways including PBDE contaminated dust and air have been studied to better characterize routes of PBDE intake into humans. ^ The scientific literature on PBDE levels in household dust reports higher PBDE concentration in dust than that found in dryer lint; levels in the U.S are elevated compared to other countries with congeners such as BDE 47, 99, 100 and 209 predominating. The United Kingdom has elevated BDE 209 due to high usage of Deca commercial mixture. These studies suggest that indoor PBDE contamination through household dust could be a potential source of PBDE exposure and body burden especially in young children. ^ PBDE levels in dryer lint from U.S ranged from 321 to 3073 ng/g (Mean: 1138 ng/g, Median: 803 ng/g) and from Germany were from 330 to 2069 ng/g (Median: 71ng/g, Mean: 361 ng/g). High median levels in U.S samples indicate contamination of lint with PBDEs although the source of the PBDEs in lint may be from dryer electrical components or air deposition onto clothes, lint may be one source of PBDE exposure to humans. ^