[Combination of thymidine and dexamethasone increases the K562 tumor cells sensitivity to human leukocytes cytotoxicity].
The influence of the number of differentiating agents on sensitivity of human erythroleukemic cells K562 to human leukocyte-mediated non-MHC-restricted lysis was studied. It has been shown that a 4-day treatment of cells K562 by dexamethasone (1 microM) or phorbol-12-myristate-13-acetate (100 nM) leads to a significant decrease in sensitivity of the treated cells to non-specific lysis mediated by human leukocytes. On the contrary, the treatment of cells K562 by a combination of dexamethasone and thymidine (2 mM) leads to an increased sensitivity of the treated cancer cells to non-specific lysis mediated by the above effector cells, compared with the situation when these cells were treated by dexamethasone only. The treatment of cells K562 by a combination of thymidine and phorbol-12-myristate-13-acetate demonstrates a tendency (P < 0.1) to increase the sensitivity to non-specific lysis mediated by human leukocytes, as compared with the cases, when these cells were treated by phorbol ester only. It has been shown that the changes in K562 cell sensitivity to lytic action of leukocytes, under the chosen incubation time and doses of the used agents, well compare with the changes of erythroid differentiation of the cancer cells in the same conditions.
Anisimov
A G
AG
Department of Biochemistry, Petrozavodsk State University. anisimov@mainpgu.karelia.ru
Chekmasova
A A
AA
Volkova
T O
TO
Nemova
N N
NN
D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology* / Q000627:therapeutic use; D002454:Cell Differentiation / Q000187:drug effects; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D003907:Dexamethasone / Q000494:pharmacology* / Q000627:therapeutic use; D004347:Drug Interactions; D006801:Humans; D020014:K562 Cells; D004915:Leukemia, Erythroblastic, Acute / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology; D007962:Leukocytes / Q000276:immunology / Q000473:pathology; D013936:Thymidine / Q000494:pharmacology* / Q000627:therapeutic use
D018931:Antineoplastic Agents, Hormonal; D003907:Dexamethasone; D013936:Thymidine