title: Estradiol receptors in subpopulations of breast cancer cells isolated from human primary tumors.
abstract: Cancer cells isolated from biopsy specimens from seven women with primary breast cancer were analyzed for estradiol receptors. The cells were separated into subpopulations using the techniques of velocity centrifugation, buoyant density centrifugation, and density gradient electrophoresis. It was found that only large breast cancer cells (with diameters between 10.1-18.5 micrometers) concentrate tritiated estradiol. The total population of cancer cells has diameters between 5.6-18.5 micrometers, and the proportion of large cancer cells from different tumors varies from 8-59% of the total population. It is suggested that clinical regression following endocrine ablation is related to the proportion of large cancer cells and to the concentration of estradiol receptors in these cells.
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism*; D002469:Cell Separation / Q000379:methods; D002498:Centrifugation / Q000379:methods; D004586:Electrophoresis; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D006801:Humans; D011959:Receptors, Estradiol; D011960:Receptors, Estrogen / Q000032:analysis*
chemical_list: D011959:Receptors, Estradiol; D011960:Receptors, Estrogen; D004958:Estradiol