Comparison of Short-Term Estrogenicity Tests for Identification of Hormone-Disrupting Chemicals

The aim of this study was to compare results obtained by eight different short-term assays of estrogenlike actions of chemicals conducted in 10 different laboratories in five countries. Twenty chemicals were selected to represent direct-acting estrogens, compounds with estrogenic metabolites, estrogenic antagonists, and a known cytotoxic agent. Also included in the test panel were 17β-estradiol as a positive control and ethanol as solvent control. The test compounds were coded before distribution. Test methods included direct binding to the estrogen receptor (ER), proliferation of MCF-7 cells, transient reporter gene expression in MCF-7 cells, reporter gene expression in yeast strains stably transfected with the human ER and an estrogen-responsive reporter gene, and vitellogenin production in juvenile rainbow trout. 17β-Estradiol, 17α-ethynyl estradiol, and diethylstilbestrol induced a strong estrogenic response in all test systems. Colchicine caused cytotoxicity only. Bisphenol A induced an estrogenic response in all assays. The results obtained for the remaining test compounds—tamoxifen, ICI 182.780, testosterone, bisphenol A dimethacrylate, 4-n-octylphenol, 4-n-nonylphenol, nonylphenol dodecylethoxylate, butylbenzylphthalate, dibutylphthalate, methoxychlor, o,p′-DDT, p,p′-DDE, endosulfan, chlomequat chloride, and ethanol—varied among the assays. The results demonstrate that careful standardization is necessary to obtain a reasonable degree of reproducibility. Also, similar methods vary in their sensitivity to estrogenic compounds. Thus, short-term tests are useful for screening purposes, but the methods must be further validated by additional interlaboratory and interassay comparisons to document the reliability of the methods

Male reproductive health and environmental xenoestrogens

EHP is a publication of the U.S. government. Publication of EHP lies in the public domain and is therefore without copyright. Research articles from EHP may be used freely; however, articles from the News section of EHP may contain photographs or figures copyrighted by other commercial organizations and individuals that may not be used without obtaining prior approval from both the EHP editors and the holder of the copyright. Use of any materials published in EHP should be acknowledged (for example, "Reproduced with permission from Environmental Health Perspectives") and a reference provided for the article from which the material was reproduced.Male reproductive health has deteriorated in many countries during the last few decades. In the 1990s, declining semen quality has been reported from Belgium, Denmark, France, and Great Britain. The incidence of testicular cancer has increased during the same time incidences of hypospadias and cryptorchidism also appear to be increasing. Similar reproductive problems occur in many wildlife species. There are marked geographic differences in the prevalence of male reproductive disorders. While the reasons for these differences are currently unknown, both clinical and laboratory research suggest that the adverse changes may be inter-related and have a common origin in fetal life or childhood. Exposure of the male fetus to supranormal levels of estrogens, such as diethlylstilbestrol, can result in the above-mentioned reproductive defects. The growing number of reports demonstrating that common environmental contaminants and natural factors possess estrogenic activity presents the working hypothesis that the adverse trends in male reproductive health may be, at least in part, associated with exposure to estrogenic or other hormonally active (e.g., antiandrogenic) environmental chemicals during fetal and childhood development. An extensive research program is needed to understand the extent of the problem, its underlying etiology, and the development of a strategy for prevention and intervention.Supported by EU Contract BMH4-CT96-0314

Optimizing Staining Protocols for Laser Microdissection of Specific Cell Types from the Testis Including Carcinoma In Situ

Microarray and RT-PCR based methods are important tools for analysis of gene expression; however, in tissues containing many different cells types, such as the testis, characterization of gene expression in specific cell types can be severely hampered by noise from other cells. The laser microdissection technology allows for enrichment of specific cell types. However, when the cells are not morphologically distinguishable, it is necessary to use a specific staining method for the target cells. In this study we have tested different fixatives, storage conditions for frozen sections and staining protocols, and present two staining protocols for frozen sections, one for fast and specific staining of fetal germ cells, testicular carcinoma in situ cells, and other cells with embryonic stem cell-like properties that express the alkaline phosphatase, and one for specific staining of lipid droplet-containing cells, which is useful for isolation of the androgen-producing Leydig cells. Both protocols retain a morphology that is compatible with laser microdissection and yield RNA of a quality suitable for PCR and microarray analysis

Split T Cell Tolerance against a Self/Tumor Antigen: Spontaneous CD4+ but Not CD8+ T Cell Responses against p53 in Cancer Patients and Healthy Donors

Analyses of NY-ESO-1-specific spontaneous immune responses in cancer patients revealed that antibody and both CD4+ and CD8+ T cell responses were induced together in cancer patients. To explore whether such integrated immune responses are also spontaneously induced for other tumor antigens, we have evaluated antibody and T cell responses against self/tumor antigen p53 in ovarian cancer patients and healthy individuals. We found that 21% (64/298) of ovarian cancer patients but no healthy donors showed specific IgG responses against wild-type p53 protein. While none of 12 patients with high titer p53 antibody showed spontaneous p53-specific CD8+ T cell responses following a single in vitro sensitization, significant p53-specific IFN-γ producing CD4+ T cells were detected in 6 patients. Surprisingly, similar levels of p53-specific CD4+ T cells but not CD8+ T cells were also detected in 5/10 seronegative cancer patients and 9/12 healthy donors. Importantly, p53-specific CD4+ T cells in healthy donors originated from a CD45RA− antigen-experienced T cell population and recognized naturally processed wild-type p53 protein. These results raise the possibility that p53-specific CD4+ T cells reflect abnormalities in p53 occurring in normal individuals and that they may play a role in processes of immunosurveillance or immunoregulation of p53-related neoplastic events

Intra-Genomic Ribosomal RNA Polymorphism and Morphological Variation in Elphidium macellum Suggests Inter-Specific Hybridization in Foraminifera

Elphidium macellum is a benthic foraminifer commonly found in the Patagonian fjords. To test whether its highly variable morphotypes are ecophenotypes or different genotypes, we analysed 70 sequences of the SSU rRNA gene from 25 specimens. Unexpectedly, we identified 11 distinct ribotypes, with up to 5 ribotypes co-occurring within the same specimen. The ribotypes differ by varying blocks of sequence located at the end of stem-loop motifs in the three expansion segments specific to foraminifera. These changes, distinct from typical SNPs and indels, directly affect the structure of the expansion segments. Their mosaic distribution suggests that ribotypes originated by recombination of two or more clusters of ribosomal genes. We propose that this expansion segment polymorphism (ESP) could originate from hybridization of morphologically different populations of Patagonian Elphidium. We speculate that the complex geological history of Patagonia enhanced divergence of coastal foraminiferal species and contributed to increasing genetic and morphological variation

Expression of MAGE-C1/CT7 and selected cancer/testis antigens in ovarian borderline tumours and primary and recurrent ovarian carcinomas

MAGE-C1/CT7, NY-ESO-1, GAGE and MAGE-A4 are members of the cancer/testis (CT) antigen family, which have been proposed as potential targets for cancer immunotherapy. To determine the prevalence and biologic relevance of the novel CT antigen MAGE-C1/CT7 and other antigens, 36 ovarian borderline tumours (BTs), 230 primary ovarian carcinomas (OCs) and 80 recurrent OCs were immunohistochemically analysed using the monoclonal antibodies CT7-33 (MAGE-C1/CT7), E978 (NY-ESO-1), clone 26 (GAGE) and 57B (MAGE-A4). Positivity of at least one CT antigen was present in 39.5 % (81/205) of primary OC and in 50 % (26/52) of all recurrences. Expression of the novel CT antigen MAGE-C1/CT7 was most commonly seen with positivity in 24.5 % of primary and 35.1 % of recurrent OC. MAGE-A4, GAGE and NY-ESO-1 expressions were seen in 22.7, 13.9 and 7.1 % of primary and 22.6, 17.5 and 8.9 % of recurrent OC, respectively. Analysis of histological subtypes (serous, endometrioid, clear cell, mucinous and transitional) exhibited variable expression with negativity in all mucinous OC. High-grade serous OC revealed CT antigen expression in 5.6 to 28 % with MAGE-C1/CT7 being the most frequent, but without correlation with stage or overall survival. MAGE-C1/CT7 expression and coexpression of CT antigens were significantly correlated with grade of endometrioid OC. None of the BT showed CT antigen expression. No significant correlation was seen with stage, overall survival or response to chemotherapy. In summary, CT antigens are expressed in a certain subset of OC with no expression in BT or OC of mucinous histology. These findings may have implications for the design of polyvalent vaccination strategies for ovarian carcinomas

Exposição ambiental a interferentes endócrinos com atividade estrogênica e sua associação com distúrbios puberais em crianças Environmental exposure to endocrine disruptors with estrogenic activity and the association with pubertal disorders in children

A substância exógena que causa efeitos adversos na saúde de um organismo ou sua descendência, como resultado de distúrbios na função hormonal, é denominada interferente endócrino. Nos últimos anos, produtos ambientais com atividades hormonais têm sido documentados como causadores de anormalidades puberais ou reprodutivas em animais. Os poucos casos comprovados em humanos foram aqueles relacionados a exposições acidentais. Apesar disso, pediatras e pais recomendam a suspensão de todos os alimentos potencialmente contaminados, em especial carne (aves, gado) e derivados da soja quando a criança apresenta alguma alteração puberal. Estas recomendações, se não embasadas cientificamente, podem ter conseqüências deletérias, não apenas pela eliminação de fontes protéicas da dieta, como também por retardar a investigação de causas tratáveis. Por outro lado, a não investigação dos efeitos adversos destes produtos é da mesma forma danosa. Esta revisão descreve os principais interferentes endócrinos responsáveis por alterações puberais em humanos e conclui que, excetuando exposições acidentais a altas quantidades destes produtos, mais estudos são necessários para responsabilizar a ação crônica e em baixas doses destas substâncias na alteração do tempo de desenvolvimento puberal em nossa espécie.<br>Endocrine disruptors are exogenous substances with adverse health effects in intact organisms or their progeny, secondary to changes in endocrine function. Recent years have witnessed constant reports of environmental factors with hormone-like effects causing pubertal or reproductive abnormalities in animals. The few cases proven to be associated with pubertal disorders in humans have been related to accidental exposure. Nevertheless, pediatricians and parents recommend suspending all possible estrogen-contaminated food, especially meat (poultry, beef) and soy products, when the child presents with a pubertal disorder. These recommendations, if not scientifically sound, may have deleterious consequences by eliminating sources of dietary protein and possibly delaying the investigation of other potential and treatable causes. On the other hand, not investigating potential side effects of these products could have similar harmful effects. The current article describes the main endocrine disruptors associated with pubertal disorders in humans and concludes that except for accidental exposure to high doses, more research is needed on the effects of chronic and low-dose exposures in altering human pubertal development