Reversal of multidrug resistance in leukemic cell line K562/AO2 by chlordelazine in vitro.
- Author:
Li-jun CHEN
1
;
Shao-hua SHEN
;
Hong-mei WANG
;
Xin YE
;
Sha-yi JIANG
;
Fei GAO
;
Gui-mei LI
Author Information
- Publication Type:Journal Article
- MeSH: ATP-Binding Cassette, Sub-Family B, Member 1; genetics; Antiemetics; pharmacology; Cell Division; drug effects; Chlorpromazine; pharmacology; Drug Resistance, Multiple; drug effects; genetics; Drug Resistance, Neoplasm; drug effects; Flow Cytometry; Humans; K562 Cells; RNA, Messenger; genetics; metabolism; Reverse Transcriptase Polymerase Chain Reaction
- From: Chinese Journal of Pediatrics 2003;41(7):525-527
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVESome recent studies revealed that phenthiazine might be able to reverse tumor cell drug-resistance. Chlorderazin belongs to the phenthiazine compounds. The study aimed to investigate the reversing effect and mechanism of chlorderazin on multidrug resistance of leukemic cell line K562/AO2.
METHODS(1) The cytotoxicities of chlorderazin were assayed with the tetrazolium dye, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. (2) The reverse effect of chlorderazin on K562/AO2 cells was analyzed with MTT method. The multidrug resistance reversal index (RI) was equal to the ratio of control group IC(50)/test group half inhibition concentration IC(50). (3) The intracellular daunorubicin (DNR) concentrations were measured by the flow cytometry. (4) Mdr1 mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR). The ratio of mdr-1/beta-actin density was calculated.
RESULTS(1) Chlorderazin 3 micro g/ml showed little toxicity to K562/AO2 cells and the suppression rate was less than 5%, so the concentration of 3 micro g/ml chlorderazin was selected as the experiment concentration. (2) The cytotoxicities of DNR to K562/AO2 were enhanced by 3 micro g/ml of chlorderazin (P < 0.05) and RI was 1.901. (3) Chlorderazin of 3 micro g/ml could increase the intracellular DNR accumulation significantly (P < 0.05), and the fluorescence staining by the flow cytometry was higher (250.95 +/- 18.96) than the control group (112.75 +/- 15.78) and shift right in K562/AO2 cells treated with chlorderazin, and the difference was significant (P < 0.05). (4) Chlorderazin has no significant influence to the expression level of mdr-1 mRNA. Both test group and control group showed a clear mdr-1 mRNA band located at the position of 157 kb. The ratios of mdr-1/beta-actin density were 0.414 +/- 0.012 in the test group and 0.447 +/- 0.027 in the control group, respectively, and the difference was not significant (P > 0.05).
CONCLUSIONChlorderazin could reverse the multidrug resistance by increasing the intracellular DNR accumulation in K562/AO2 cells. The effects had no correlation to the mdr-1 gene. Further study is needed.
