Abstract
Endometrial cells isolated from uteri of ovariectomized rats were treated in vitro with 1 X 10(-9) M estradiol-17 beta (E2beta) to analyze early changes in membrane properties during hormone-induced growth. After 30-min exposure to E2beta at 22 degrees C, cells exhibited an enhanced capacity to bind erythrocytes (hemadsorption) in the presence of concanavalin A (Con A) to 237% of the level in paired controls. Fluorescence microscopy revealted that approximately 25% of cells exposed to E2beta, but not estradiol-17 alpha (E2alpha), showed a redistribution into polar clusters of Con A-binding sites that were dispersed in random patches at the external surfaces of control cells. These hormore-induced membrane alterations were abolished by prior treatment of cells with inhibitors of thiol proteinase activity of the cathepsin B1 (CB1) type, such as leupeptin and iodoacetate. Leupeptin at 4.5 X 10(-7) M also reduced the affinity of [3H]E2beta binding to intact cells but did not influence specific binding of the hormone to macromolecular components of cytosol. A pronounced increase in the availability of endogenous CB1, But not of alkaline phosphatase, succinate, or lactate dehydrogenase, in the extracellular media was elicited within 30 min after E2beta treatment. In cells cultured in chemically defined medium for up to 48 h, E2beta, but not E2alpha, enhanced cell proliferation and stimulated [3H]thymidine incorporation into macromolecular form. These E2beta-induced effects were abolished by prior treatment of cells with liposome-entrapped leupeptin at a final concentration of 7 X 10(-8) M. The net rate of intercellular adhesion among endometrial cells was also enhanced by E2beta. This hormonal response was diminished by prior exposure to leupeptin. Fractionation of cells by selection for adhesiveness due to E2beta exposure for 30 min yielded a subpopulation of rapidly dividing cells which surpassed their less adhesive counterparts in cathepsin secretion and in Con A-mediated hemadsorption. These results indicate that leupeptin-sensitive proteinase activity may contribute to membrane and growth modifications elicited by E2beta treatment in endometrial cells.
Full Text
The Full Text of this article is available as a PDF (1.5 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Anderson J. N., Peck E. J., Jr, Clark J. H. Estrogen-induced uterine responses and growth: relationship to receptor estrogen binding by uterine nuclei. Endocrinology. 1975 Jan;96(1):160–167. doi: 10.1210/endo-96-1-160. [DOI] [PubMed] [Google Scholar]
- Buller R. E., O'Malley B. W. The biology and mechanism of steroid hormone receptor interaction with the eukaryotic nucleus. Biochem Pharmacol. 1976 Jan;25(1):1–12. doi: 10.1016/0006-2952(76)90164-7. [DOI] [PubMed] [Google Scholar]
- Cohn Z. A. Macrophage physiology. Fed Proc. 1975 Jul;34(8):1725–1729. [PubMed] [Google Scholar]
- Jackson V., Chalkley R. The cytoplasmic estradiol receptors of bovine uterus. Their occurrence, interconversion, and binding properties. J Biol Chem. 1974 Mar 10;249(5):1627–1636. [PubMed] [Google Scholar]
- Jensen E. V., Suzuki T., Kawashima T., Stumpf W. E., Jungblut P. W., DeSombre E. R. A two-step mechanism for the interaction of estradiol with rat uterus. Proc Natl Acad Sci U S A. 1968 Feb;59(2):632–638. doi: 10.1073/pnas.59.2.632. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Katz J., Troll W., Adler S. W., Levitz M. Antipain and leupeptin restrict uterine DNA synthesis and function in mice. Proc Natl Acad Sci U S A. 1977 Sep;74(9):3754–3757. doi: 10.1073/pnas.74.9.3754. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MUSA B. U., DOE R. P., SEAL U. S. PURIFICATION AND PROPERTIES OF HUMAN LIVER BETA-GLUCURONIDASE. J Biol Chem. 1965 Jul;240:2811–2816. [PubMed] [Google Scholar]
- McIlhinney A., Hogan B. L. Effect of inhibitors of proteolytic enzymes on the growth of normal and polyoma transformed BHK cells. Biochem Biophys Res Commun. 1974 Sep 9;60(1):348–354. doi: 10.1016/0006-291x(74)90211-3. [DOI] [PubMed] [Google Scholar]
- Nicolson G. L. Trans-membrane control of the receptors on normal and tumor cells. II. Surface changes associated with transformation and malignancy. Biochim Biophys Acta. 1976 Apr 30;458(1):1–72. doi: 10.1016/0304-419x(76)90014-7. [DOI] [PubMed] [Google Scholar]
- Notides A. C., Hamilton D. E., Rudolph J. H. The action of a human uterine protease on the estrogen receptor. Endocrinology. 1973 Jul;93(1):210–216. doi: 10.1210/endo-93-1-210. [DOI] [PubMed] [Google Scholar]
- Pietras R. J., Szego C. M. Steroid hormone-responsive, isolated endometrial cells. Endocrinology. 1975 Apr;96(4):946–954. doi: 10.1210/endo-96-4-946. [DOI] [PubMed] [Google Scholar]
- Pietras R. J., Szego C. M. Surface modifications evoked by estradiol and diethylstilbestrol in isolated endometrial cells: evidence from lectin probes and extracellular release of lysosomal protease. Endocrinology. 1975 Dec;97(6):1445–1454. doi: 10.1210/endo-97-6-1445. [DOI] [PubMed] [Google Scholar]
- Schneider S. L., Dao T. L. Effect of Ca2+ and salt on forms of estradiol cytoplasmic receptor in human neoplastic breast tissue. Cancer Res. 1977 Feb;37(2):382–387. [PubMed] [Google Scholar]
- Sherman M. R., Pickering L. A., Rollwagen F. M., Miller L. K. Mero-receptors: proteolytic fragments of receptors containing the steroid-binding site. Fed Proc. 1978 Feb;37(2):167–173. [PubMed] [Google Scholar]
- Terenius L. SH-groups essential for estrogen uptake and retention in the mouse uterus. Mol Pharmacol. 1967 Sep;3(5):423–428. [PubMed] [Google Scholar]
- Williams D., Gorski J. Preparation and characterization of free cell suspensions from the immature rat uterus. Biochemistry. 1973 Jan 16;12(2):297–306. doi: 10.1021/bi00726a019. [DOI] [PubMed] [Google Scholar]
- de Duve C., de Barsy T., Poole B., Trouet A., Tulkens P., Van Hoof F. Commentary. Lysosomotropic agents. Biochem Pharmacol. 1974 Sep 15;23(18):2495–2531. doi: 10.1016/0006-2952(74)90174-9. [DOI] [PubMed] [Google Scholar]