Changes in the concentrations of receptors of insulin-like growth factor-I, epithelial growth factor, oestrogens and progestagens in adenomyosis foci, endometrium and myometrium of women during menstrual cycle.

Concentrations of receptors of insulin-like growth factor-I (IGF-I-R), epithelial growth factor (EGF-R), oestrogen (ER), and progesterone (PR) in the adenomyosis foci, endometrium and myometrium of women during the menstrual cycle were studied. Cell membrane levels of IGF-I-R and EGF-R, cytosol and nuclear oestrogen (ERc and ERn, respectively) and cytosol progesterone (PRc) receptors were assayed in 37 samples of adenomyosis foci, 46 of endometrium and 50 of myometrium using the radioligand method. It was found that concentrations of ER and PR in all studied tissues were significantly higher in the proliferative phase than in the secretory phases. In the endometrium a similar difference concerned only the ERn but not the ERc. Adenomyosis foci as compared to endometrium and myometrium showed the highest ERn and PRc concentrations during the proliferative and secretory phase. Adenomyosis foci and myometrium contained significantly higher concentrations of IGF-I-R in the proliferative phase than in the secretory phase. In the endometrium a menstrual cycle-related difference in concentration of IGF-I-R was not significant. In the endometrium however the concentration of EGF-R was over twice as high in the proliferative phase than in the secretory phase. No significant difference in the concentrations of EGF-R in adenomyosis foci and in myometrium during the menstrual cycle was noted. The findings show that changes in regulation of the concentrations of IGF-I-R, EGF-R, ER and PR in the uterus of women during menstrual cycles are related to the tissular localization of these receptors.

Epidermal growth factor receptor and estrogen and progesterone receptors in breast cancers of premenopausal and postmenopausal patients.

AIMS AND BACKGROUND: The purpose of our research was to investigate the relations between the levels of epidermal growth factor receptor and estrogen and progesterone receptors in breast cancers of premenopausal and postmenopausal Polish women. METHODS: Cell membrane levels of epidermal growth factor receptor (EGF-R), and cytosol (c) estrogen (ER) and progesterone (PR) receptors were determined in 221 specimens of primary breast cancers. ERc and PRc were assayed using the dextran-coated charcoal procedure, and EGF-R were assayed by the radioligand method of specific saturation of the crude membrane fraction with 125I-EGF RESULTS: A statistically significant inverse correlation was found in all tumors between the concentrations of EGF-R and ERc, whereas for PRc significance of this correlation was not fully confirmed. ERc concentrations in tumors were positively correlated with age of patients, whereas EGF-R and PRc were not. In all, in premenopausal, and in postmenopausal EGF-R-positive tumors (> or = 10 fmol/mg of membrane protein), mean concentrations of ERc did not differ significantly. These groups of tumors seem to be homogeneous with respect to ERc concentrations. In EGF-R-negative (< 10 fmol/mg of membrane protein) postmenopausal tumors, the mean ERc concentration was significantly higher than in premenopausal tumors, hence these groups of tumors appear to be heterogeneous with regard to ERc contents: CONCLUSIONS: The present findings may have significance in differentiation of postmenopausal breast cancer.

The role of vacuolar digestive system in preventing cadmium poisoning in Acanthamoeba castellanii.

Constituents showing cadmium affinity were found in digestive residues of the vacuolar digestive system in Acanthamoeba. Cadmium was detected by means of X-ray analysis in complexes appearing both in residues included within the digestive vacuoles and in those egested outside the cell. The digestive vacuolar system in Acanthamoeba castellanii is characterized by a particularly high turnover rate (4). Confronted with this fact, results of the present study suggest that the system is able to egest rapidly the ligand-bound cadmium. In this way protects the amoeba against serious toxic effects of the Cd-polluted environment.

Replacement of calcium by cadmium ions from Ca-affinity sites localized in different cytoplasmic compartments of Acanthamoeba cells.

In Acanthamoeba cells both Ca and Cd may be precipitated in different cytoplasmic compartments forming electron-opaque deposits, as shown in cells treated with glutaraldehyde supplied with either Ca or Cd respectively. It was found by semiquantitative X-ray microanalysis that the transfer of cells containing Ca-deposits to glutaraldehyde supplied with Cd causes a considerable replacement of Ca by Cd: in deposits formed at cell membrane, in cytoplasm, and in mitochondria the total weight percentage of Cd amounted to over 90, only in deposits formed in vacuoles the value was about 80. The replacement was not prevented by the presence of Ca in the transfer medium. When cells containing Cd-deposits were transferred to Ca-supplied medium, Cd predominated as well, its total weight percentage also amounting to over 90 in all the examined deposits. The results suggest that calcium bound in different cell structures may be easily replaced by cadmium, but not conversely, which suggests that Cd is more firmly than calcium linked to many cell constituents well preserved by fixation.