title: [Evaluation of the effectiveness of tamoxifen in malignant breast tumors: new approaches].
abstract: It has been shown that 17 beta-estradiol stimulates the cycle of phospholipid conversion in the breast tumor cells. The action of tamoxifen on antiestrogen cells is not limited by weakening the stimulating effect of 17 beta-estradiol on the exchange of intracellular phospholipids, but gives rise to a more complicated pattern of changes: inhibited incorporation of 32-P-phosphatidylcholine (PC) and activated exchange of phosphoinositides (PI). The experimental findings of 53 breast tumors have indicated that in 47.2% of cases Tamoxifen alters the PC/PI ratio and causes its 2-fold increase. Such alterations have been found to be induced by the ability of Tamoxifen to suppress the activity of protein kinase C that regulates the synthesis of PC and PI. It is suggested that the revealed capacity of Tamoxifen to change the rate of intracellular phospholipid conversion might be used for evaluating the efficiency of this agent on malignant tumors.
authors.forename: M A
authors.initials: MA
authors.lastname: Krasil'nikov
authors.forename: V A
authors.initials: VA
authors.lastname: Shatskaia
authors.forename: V D
authors.initials: VD
authors.lastname: Ermilova
authors.forename: V P
authors.initials: VP
authors.lastname: Letiagin
mesh_terms: D001345:Autoradiography; D001943:Breast Neoplasms / Q000201:enzymology / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D006801:Humans; D010713:Phosphatidylcholines / Q000378:metabolism; D010716:Phosphatidylinositols / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D010761:Phosphorus Radioisotopes; D011493:Protein Kinase C / Q000187:drug effects / Q000378:metabolism; D013629:Tamoxifen / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism
chemical_list: D010713:Phosphatidylcholines; D010716:Phosphatidylinositols; D010743:Phospholipids; D010761:Phosphorus Radioisotopes; D013629:Tamoxifen; D004958:Estradiol; D011493:Protein Kinase C
vernacular_title: Opredelenie éffektivnosti deĭstviia tamoksifena na zlokachestvennye opukholi molochnoĭ zhelezy: novye podkhody.