Long-Term Effects of Fetal Exposure to Low Doses of the Xenoestrogen Bisphenol-A in the Female Mouse Genital Tract1

Developmental exposure to estrogenic chemicals induces morphological, functional, and behavioral anomalies associated with reproduction. Humans are routinely exposed to bisphenol-A (BPA), an estrogenic compound that leaches from dental materials and plastic food and beverage containers. The aim of the present study was to determine the effects of in utero exposure to low, environmentally relevant doses of BPA on the development of female reproductive tissues in CD-1 mice. In previous publications, we have shown that this treatment alters the morphology of the mammary gland and affects estrous cyclicity. Here we report that in utero exposure to 25 and 250 ng BPA/ kg of body weight per day via osmotic pumps implanted into pregnant dams at Gestational Day 9 induces alterations in the genital tract of female offspring that are revealed during adulthood. They include decreased wet weight of the vagina, decreased volume of the endometrial lamina propria, increased incorporation of bromodeoxyuridine into the DNA of endometrial gland epithelial cells, and increased expression of estrogen receptor-alpha (ERalpha) and progesterone receptor in the luminal epithelium of the endometrium and subepithelial stroma. Because ERalpha is known to be expressed in these estrogen-target organs at the time of BPA exposure, it is plausible that BPA may directly affect the expression of ER-controlled genes involved in the morphogenesis of these organs. In addition, BPA-induced alterations that specifically affect hypothalamic-pituitary-gonadal axis function may further contribute to the anomalies observed at 3 mo of age, long after the cessation of BPA exposure.

Bcl-2 correlates with tumor ploidy and nuclear morphology in early stage prostate carcinoma. A fine needle aspiration biopsy study

We evaluated the nuclear morphology, ploidy, bcl-2 expression and in situ apoptosis in sections of fine-needle aspiration (FNA) biopsy specimens of thirty-one randomly selected Stage B prostate carcinomas. Sections of paraffin-embedded pelleted cells obtained from FNA biopsy specimens were studied. Nuclear grade was determined according to the WHO system. Nuclear morphometry and DNA ploidy were carried out using an automated image analyzer. We used immunostaining and the TUNEL method to evaluate bcl-2 expression and in situ apoptosis. The median nuclear area increased with increasing nuclear grade. Ploidy analysis showed that 54.8% of tumors were diploid, 3.2% tetraploid and 41.9% aneuploid. Bcl-2 overexpression was found in 10 of 31 tumors. There was a significant positive correlation between bcl-2 expression and nuclear area (r(s): 0.45 p < 0.01). Nine of ten bcl-2-positive tumors had a nuclear area larger than the median of the series, and 70% of bcl-2-positive tumors were of the aneuploid type. The apoptotic index had a negative correlation with nuclear area, and the lowest indexes were found in aneuploid tumors. Bcl-2 expression showed a highly significant association with both parameters of high aggressiveness: nuclear size and aneuploidy. The combined evaluation of nuclear morphology, ploidy and cell survival parameters might better identify patients with poor prognosis among early stage prostate carcinomas diagnosed by FNA biopsies.

Proliferative activity and steroid hormone receptor status in male breast carcinoma

Hormonal factors have been implicated in the development of both female and male breast cancers (MBC). However, MBCs are rare and seem to have different biological behavior than those of females. The aim of this study was to evaluate proliferative activity and to establish an association with steroid hormone receptor concentration and clinicopathological parameters in MBC. Proliferative activity was assessed in 18 MBC by mitotic figure counts and immunohistochemical evaluation of MIB-1 and proliferating cell nuclear antigen (PCNA). Estrogen (ER), progesterone (PR) and androgen (AR) receptors were evaluated in serial section from the same tumor by immunohistochemistry. PCNA (range 17-73%; mean, 51.6%) and MIB-1 (range 18.5-58%; mean 38.4%) were positive correlated with the mitotic rate. High proliferative activity assessed either by mitotic index or MIB-1 expression was associated with more poorly differentiated tumors. Sixty one percent (11/18) of the tumors were ER+, 72% (13/18) PR+ and 38.5% (5/13) AR+. Proliferative activity in tumors displaying ER+/PR+ phenotype showed a tendency to be higher than in ER-/PR- tumors. This difference was statistically significant when MIB-1 expression was used as proliferation marker. An association between AR concentration and age at diagnosis was found; in the AR negative group (8/13) mean age at diagnosis was 54.4 +/- 7.3 which was significantly lower than the age of patients with AR+ tumors, 63.2 +/- 11.1 (5/13). Results presented here show that decreased androgen action (AR-) within the breast might contribute to an earlier development of MBC. Besides that, the presence of ER and PR in carcinoma cells is considered to provide a growth advantage as shown by the positive association between the phenotype (ER+/PR+) and high proliferative activity. These results add information for a better understanding of hormonal control of MBC growth and development.

Processing fine needle aspirates of prostate carcinomas for standard immunocytochemical studies and in situ apoptosis detection

A method is described for making permanent histological sections of prostate carcinoma material obtained by fine needle aspiration (FNA) under ecography guidance. Smears made from prostate aspirates were used for diagnosis and from the same patient remaining aspirates were expelled into fixative filled microcentrifuge tube. Aspirates were pelleted and further processed to paraffin blocks. Permanent histological sections were obtained and each section was defined as satisfactory when it contained about 200 intact tumor cells. We have used these tumor sections and immunocytochemistry (ICC) procedures to study molecular biological marker expression. The technique described here has proven to be easy to use and offered a fast, reliable and cost-effective method to obtain suitable samples for standard ICC and in situ apoptosis detection from FNA prostate carcinoma. The method should be equally suitable for outpatient use on other tumors in which FNA and ICC or in situ apoptosis detection is likely to be helpful.

Antigen retrieval immunohistochemistry: past, present, and future

The antigen retrieval (AR) technique, which is predominantly based on high-temperature heating of tissues, is used as a non-enzymatic pretreatment for immunohistochemical staining of formalin-fixed, paraffin-embedded tissue sections. It has been widely applied in pathology and analytical morphology. The existence of a growing body of literature on the AR technique raises a number of interesting issues for the further development of AR. These issues include the use of a "test battery" and the concept of "maximal retrieval" applied to the selection of optimal test protocols for the standardization of AR.

Lack of relationship between the expression of Hsp27 heat shock estrogen receptor-associated protein and estrogen receptor or progesterone receptor status in male breast carcinoma

Estrogen, through estrogen receptors (ERs), may regulate the synthesis of progesterone receptors (PRs) and of a heat shock estrogen receptor-associated protein (hsp27). In female breast carcinoma (FBC) both proteins serve as surrogate indicators for the presence of functional ERs. In addition, the expression of these proteins was related to other prognostic indicators of value in female breast tumours. Endocrine disorders, hormone therapy and altered estrogen metabolism have been associated with the development of male breast cancer (MBC), suggesting that evaluation of the expression of ER, PR and hsp27 might improve our understanding of the biology of this tumour. ER and PR status and hsp27 expression were evaluated by immunohistochemistry in 16 primary MBC patients. The interrelationships between these parameters were established and compared with the clinicopathological data on the tumours. Ten (56%) MBC patients were ER-positive, 69% were PR-positive and all samples were hsp27-positive. Our series of MBC patients showed a positive correlation between ERs and PRs, however there was a lack of correlation between hsp27 and ERs or PRs. MBCs did not exhibit any correlation between the biomarkers studied and known prognostic indicators for females (e.g. Scarff-Bloom-Richardson (SBR) or modified SBR (MSBR) grade, T stage, lymph node status). This is the first published series reporting the incidence of hsp27 in MBC. The lack of association between the expression of ERs and hsp27 found in MBC differs from the results reported for FBC, moreover the expression of ERs, PRs or hsp27 did not correlate with the clinicopathological parameters that have prognostic value in females. Although the data were obtained from a relatively small sample population, our findings suggest that MBC and FBC are biologically different tumours with respect to the expression of the studied proteins.