[Effect of tetrandrine and droloxifene on the reversion of drug resistance of K562/A02 cell line and induction of apoptosis].
OBJECTIVE
To study the reversal effect of tetrandrine (Tet) and droloxifene (Drol) on multidrug resistant cell line K562/A02 and apoptosis induction.


METHODS
The cytotoxicity of daunorubicin (DNR) was assayed by MTT method. The effects of Tet and DRL, alone or combined were detected through the apoptosis of K562/A02 by agarose gel electrophoresis.


RESULTS
The cytotoxicity of DNR to K562/A02 was enhanced by 0.62 microg/ml Tet or 1.94 microg/ml Drol with IC(50) 7.28 +/- 2.06 microg/ml, 7.58 +/- 3.44 microg/ml, giving a reversal effect of 2.94 and 2.82. But IC(50) of combined Tet and Drol was 1.66 +/- 0.41 microg/ml with the reversal effect markedly increased to 12.9. Neither 0.62 microg/ml Tet nor 1.94 microg/ml Drol could induce apoptosis of K562/A02 cells.


CONCLUSIONS
Multidrug resistance (MDR) can be partially reversed by Tet or Drol, of which the combination shows a great synergistic reversal effect. The mechanism of Tet and Drol reversing multidrug resistance is not correlated with the apoptosis of K562/A02 cells.
Chen
Baoan
B
Department of Hematology, Zhongda Hospotal, Medical College of Southeast University, Nanjing 210009, China.
Dong
Ying
Y
Zhang
Peng
P
Cheng
Jian
J
Zhou
Yun
Y
Sheng
Ming
M
Wang
Ting
T
Gao
Feng
F
D000470:Alkaloids / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D017209:Apoptosis; D044182:Benzylisoquinolines; D003630:Daunorubicin / Q000494:pharmacology; D018432:Drug Resistance, Multiple / Q000502:physiology*; D019008:Drug Resistance, Neoplasm / Q000502:physiology; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D020014:K562 Cells; D013629:Tamoxifen / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D000470:Alkaloids; D000970:Antineoplastic Agents; D044182:Benzylisoquinolines; D013629:Tamoxifen; C009438:tetrandrine; D003630:Daunorubicin