title: Effects of hexestrol, medroxyprogesterone acetate and chlormadinone acetate on 7, 12-dimethylbenz [a] anthracene-induced rat mammary cancer in relation to estrogen receptor.
abstract: The effects of hexestrol (HXS), medroxyprogesterone acetate (MAP) and chlormadinone acetate (CMA) on 7, 12-dimethylbenz [a] anthracene-induced mammary cancer in rats were evaluated. As a result of successive intramuscular injections of HXS at dosages of 2 or 10 mg/kg or MAP at dosages of 24 or 120 mg/Kg, tumors were markedly reduced in size in all groups on day 7 approximately 14. These effects were the same regardless of the presence or absence of cytoplasmic estrogen receptors (ER) in tumors as determined by the dextran-coated charcoal method. Although such an effect was also seen with CMA, it was much less marked than the effects seen with HXS and MAP. The body weights of HXS-administered groups decreased considerably, whereas those of MAP-administered groups increased. These results may suggest that there is another endocrinological tumor-suppressing mechanism besides the mechanism involving the estrogen-ER system in large-dose administration of HXS and MAP.
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002715:Chlormadinone Acetate / Q000627:therapeutic use*; D003692:Delayed-Action Preparations; D005260:Female; D006589:Hexestrol / Q000627:therapeutic use*; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced* / Q000188:drug therapy* / Q000378:metabolism; D008525:Medroxyprogesterone / Q000031:analogs & derivatives* / Q000627:therapeutic use; D017258:Medroxyprogesterone Acetate; D051381:Rats; D011919:Rats, Inbred Strains; D011960:Receptors, Estrogen / Q000378:metabolism*
chemical_list: D003692:Delayed-Action Preparations; D011960:Receptors, Estrogen; D002715:Chlormadinone Acetate; D006589:Hexestrol; D015127:9,10-Dimethyl-1,2-benzanthracene; D017258:Medroxyprogesterone Acetate; D008525:Medroxyprogesterone