[Thymidine kinase activity in mammary tumors of animals exposed to estradiol as an index of tumor hormone dependence].
The effects of ovariectomy and estrogen treatment on the activity of thymidine kinase in estrogen-dependent and estrogen-independent mammary gland tumors (MGT) of experimental animals were studied. Thymidine kinase activity decreased 3-18 fold after ovariectomy in estrogen-dependent MGT only. It increased 3-7 fold again after estradiol treatment. These changes were significantly greater than those in hexokinase and glucose-6-phosphate dehydrogenase activity. High doses of estrogens (200 micrograms/day) resulted in an 1.8-3.5-fold decrease in thymidine kinase in estrogen-dependent MGT. The enzyme activity in estrogen-independent MGT did not change. It is suggested to use thymidine kinase activity as a marker of proliferative processes in evaluation of hormone-dependency of tumors and the effects of other factors on tumor growth.
D000818:Animals; D002369:Castration; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D006593:Hexokinase / Q000378:metabolism; D008325:Mammary Neoplasms, Experimental / Q000201:enzymology*; D051379:Mice; D008815:Mice, Inbred Strains; D051381:Rats; D011919:Rats, Inbred Strains; D013937:Thymidine Kinase / Q000378:metabolism*; D013997:Time Factors
D004958:Estradiol; D005954:Glucosephosphate Dehydrogenase; D006593:Hexokinase; D013937:Thymidine Kinase
Aktivnost' timidinkinazy v opukholiakh molochnykh zhelez zhivotnykh pri deĭstvii éstradiola kak pokazatel' gormonozavisimosti opukholeĭ.