Binding of fluorescein isothiocyanate conjugated lectins to MXT mouse mammary neoplasm and their relation to steroid receptor status.

As previous studies have suggested a hormone dependence of binding sites for peanut agglutinin in mammary neoplasm, this feature has been thought to be correlated to steroid receptor status. The present investigation was undertaken on a well-established ovarian-dependent cancer model in order to check this hypothesis. Sections of primitive tumor transplants as well as of tumors induced in vivo by injection of cell clones were analyzed with the use of three fluorescent lectins. The lectin binding sites were evaluated semi-quantitatively and compared with estrogen and progesterone receptor levels. Using non-parametric statistical tests, the results revealed a strong correlation between the expression of peanut agglutinin (PNA) binding sites and steroid receptor status, but only in primitive tumor transplants. No such correlation was observed in tumors induced in vivo, by injection of cell clones. No correlation between the steroid receptor status and the two other lectins (Concanavalin A and Dolichos biflorus) was observed. These data suggest that PNA can be used as a valuable histochemical tool in steroid hormone dependence study.

Hormonal regulation of uterine epithelial cell proliferation. I. Effects of estradiol or progesterone administered separately.

Using an in vivo tritiated thymidine (3H-TdR) labeling followed by autoradiography, the effects at different times before sacrifice of single or paired injections of 17-beta-estradiol (E2) or progesterone (Pg) at various concentrations were investigated in adult B6D2FI ovariectomized mouse luminal and glandular uterine epithelium. With regard to the luminal epithelium, E2 (0.25, 2.50 or 25.00 micrograms/animal) exerts a mitogenic influence which is dose-related. Pg (125, 600 or 5000 micrograms/animal) exerts a significant proliferative effect only at a high dose. With regard to glandular epithelium, E2 and Pg have an almost identical mitogenic influence which is dose-related. A two-step Pg administration (2 x 125 micrograms) inhibits cell proliferation in glandular epithelium as compared to the promoting action exerted by a single injection. No refractory response was observed after a two-step E2 administration in either the luminal or the glandular epithelium. These data demonstrate that cell proliferation in the uterine luminal epithelium of an adult B6D2F1 mouse is very sensitive to E2 but not to Pg, whereas these two steroids have a similar mitogenic influence on the cell proliferation of the glandular epithelium. Moreover, a second Pg administration seems to have an inhibiting effect on cell proliferation as compared to that exerted by the first injection performed 12 or 24 hours earlier. In contrast, the repetition of E2 treatment would seem to exert an additive effect on uterine epithelial cell proliferation. In conclusion, epithelial components of the endometrium are complex steroid targets. The two major cell types (luminal, glandular) differ in their abilities to respond to steroid stimulation by entering into DNA synthesis.

Hormonal regulation of uterine epithelial cell proliferation. II. Effects of estradiol and progesterone administered in combination.

The effects of estradiol (E2) and progesterone (Pg) administered in combination on the cell proliferation of the ovariectomized B6D2F1 mouse uterine epithelium were assessed by thymidine autoradiography. In the luminal and glandular cell populations Pg inhibits the mitogenic effect of E2 when administered simultaneously or 24 hours after E2; when Pg is given 12 hours after E2 it does not block but slows down the proliferative effect of E2, at least at the concentrations studied here. Given prior to E2, Pg rather exerts an additive (synergistic) effect on uterine epithelia. It is concluded that Pg can exert different actions on the E2- mitogenic effect induced at both luminal and glandular levels. Further investigations are needed to understand better the precise biochemical mechanisms involved in the modulating actions of these steroids on the mouse endometrium epithelial cells.

Comparison of biochemical and immunoenzymatic macromethods and a new immunocytochemical micromethod for assaying estrogen receptors in human breast carcinomas.

Estrogen receptors (ERs) were assayed in 23 breast carcinomas by: (1) the conventional biochemical assay with dextran-coated charcoal (DCC); (2) the immunoenzymatic assay using a monoclonal antibody (MAb), ER-EIA (Abbott); and (3) an original cytochemical method using another MAb, ER-ICA (Abbott). The first two techniques were performed on biopsy samples, whereas the last was carried out on fine needle aspiration (FNA) samples. The ER contents in aspirates were evaluated by: (1) scaled proportions of colored neoplastic cells; (2) scaled coloration intensity; (3) total grading (= proportion plus intensity); (4) product grading (= proportion times intensity); and (5) a new index (NI) described in this paper. The ER-EIA assay correlated best, with a high statistical significance, with the NI (P less than .001); NI was also the only index that significantly correlated (P less than .05) with the DCC results. The results show that the ER-ICA assay offers the great advantages of being applicable to FNA specimens and of producing rapidly available results. This new technique enriches the panel of MAbs for the diagnosis of adenocarcinomas and offers a new tool for the therapeutic follow-up of breast cancer patients. Our preliminary results suggest that the anti-ER MAbs might be helpful for measuring the hormone dependence of small lesions not assayable by DCC, even under endocrine therapy, thus avoiding false-negative assays.

[Immunocytochemical assay of estrogen receptors in puncture products of breast carcinomas]. / Dosage immunocytochimique du récepteur d'oestrogène dans les produits de ponctions de carcinomes mammaires.

In a pilot study, estrogen receptors (ER) were assayed on 42 surgically removed breast tumors by the following 3 methods: biochemical assay with dextran coated charcoal (DCC), Abbott immunoenzymatic (ER-EIA) and immunocytochemical (ER-ICA) technics. DCC and ER-EIA were performed on biopsy specimens while ER-ICA was run on cytocentrifugated cells obtained by fine needle aspiration (FNA). ER contents were expressed according to an index taking into account the proportion of colored neoplastic cells and the intensity of staining. Statistical correlation coefficient (Spearman and Kendall) concordance, sensitivity and specificity between the results were calculated (ER - ICA/ER - EIA: P less than 0.001, r = 0.38, concordance = 83%, sensitivity = 86%, specificity = 77%; ER - ICA/DCC: P less than 0.05, r = 0.22, concordance = 77%, sensitivity = 85%, specificity = 63%; ER - EIA/DCC: P less than 0.001, (r = 0.60). As previously reported, both immunoassays showed good agreement. The weaker but nevertheless significant correlation found with reference DCC may be due to the heterogeneity of tumoral ER content. This hypothesis is supported by the variability of ER - ICA assays on multiple FNA performed in 16 cases from our series. Use of multidirectional FNA slightly improved the results. Nevertheless, ER - ICA appear to be a good semi-quantitative method and might be helpful in the follow-up of metastasis treated with anti-estrogen, especially in small lesions not assayable by DCC.

Sexual dimorphism of the weight of the skull in African cercopithecidae (primates, catarrhini).

As we had to determine the sex of Cercopithecidae with the help of their skulls, we employed the usual method of measuring the length of their canines. Since we had to consider some doubtful cases, we wondered if we could confirm the diagnosis on the basis of another practical variable. Skull weight seemed to be one such possibility. We weighed 447 skulls from different genera and species of African Cercopithecidae. Whereas the t test confirmed the existence of a sexual dimorphism at this level, discriminant analysis gave a discriminating value to the weights of skulls.

In vitro studies of canine mammary tumors: influence of 17-beta-estradiol and progesterone on cell kinetics parameters.

Using an in vitro tritiated thymidine nuclear labeling followed by autoradiography, the effects of 17-beta-estradiol (E2) or progesterone (Pg) were studied in 30 canine mammary tumors that were incubated and hormonally stimulated in vitro. In 10 of these tumors, the synthetic (S) phase duration was also measured in absence or in presence of E2, by using a double labeling with tritiated thymidine. Our results demonstrate that E2, and, to a lesser degree, Pg can induce cell replication in both estrogen receptor-positive (ER+ PgR+) and estrogen receptor-negative (ER- PgR-) canine mammary tumors. The mitogenic effect of E2 may involve a shortening of the DNA S cell cycle phase. We have also found a significantly positive relationship between the estrogen and the progesterone receptor concentrations and the basal proliferation rate in these tumors, whereas no correlation was found between steroid receptor contents and the maximal level of stimulation achieved after E2 or Pg exposure.