Abstract |
Thirteen independently derived murine thymic lymphosarcoma lines were assayed for various aspects of sensitivity to glucocorticoid-induced cytolysis. All tumor lines were sensitive to cytolysis, as evidenced by profound tumor regression after pharmacologic doses of cortisol. All tumor lines contained about 20,000 high-affinity, dexamethasone binding sites/cell. Between 55 and 88% of these presumptive receptor sites underwent nuclear translocation during a 30-minute incubation at 37 degrees C. Dissociation constants (Kd) for the dexamethasone-receptor complex were between 1.5 and 3.6 nM in all cases. Kd for the triamcinolone acetonide-receptor complex were determined for a few tumor lines and were between 0.5 and 0.9 nM. Cytolysis-resistant subpopulations were selected by prolonged glucocorticoid treatment of BALB/c pi mice bearing tumors from seven of the lymphosarcoma lines. All seven resistant subpopulations contained about 20,000 high-affinity, dexamethasone binding sites/cell. Between 57 and 80% of these presumptive receptor sites underwent nuclear translocation under standard assay conditions. No resistant variants exhibited significantly reduced dexamethasone binding or nuclear translocation properties.
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Authors | A K Chan, E A Thompson Jr |
Journal | Journal of the National Cancer Institute
(J Natl Cancer Inst)
Vol. 71
Issue 3
Pg. 579-82
(Sep 1983)
ISSN: 0027-8874 [Print] United States |
PMID | 6577232
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Receptors, Glucocorticoid
- Receptors, Steroid
- Dexamethasone
- Hydrocortisone
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Topics |
- Animals
- Cell Nucleus
(metabolism)
- Dexamethasone
(metabolism)
- Female
- Hydrocortisone
(therapeutic use)
- Lymphoma, Non-Hodgkin
(drug therapy, physiopathology)
- Mice
- Mice, Inbred BALB C
- Receptors, Glucocorticoid
(metabolism)
- Receptors, Steroid
(metabolism)
- Sarcoma, Experimental
(drug therapy, physiopathology)
- Thymus Neoplasms
(drug therapy, physiopathology)
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