[Transfection of HL-60 cells with CYP3A5 gene induces drug-resistant phenotype].
OBJECTIVE
To investigate if CYP3A5 gene is involved in the molecular mechanisms for multiple drug resistance in leukemia cells.


METHODS
A full length cDNA of CYP3A5 gene was cloned, and a recombinant eukaryotic expression plasmid was constructed, then stably transfected cell lines were established. Furthermore, the sensitivity of those cell lines to several anticancer drugs were assessed by MTT and FCM assay.


RESULTS
The recombinant plasmid was designated as pcDNA3-CYP3A5. Transfecting HL-60 cells (which didn't show transcript of CYP3A5 gene) with recombinant plasmid pcDNA3-CYP3A5 generated HL-60/CYP3A5 cell line, and transfecting of HL-60 cells with the parental pcDNA3 vector served as control HL-60/pc cell line. Daunorubicin induced remarkable apoptosis peaks in HL-60 and HL-60/pc cells, while such effect did not occur in HL-60/CYP3A5 cells (apoptosis cell percentage were 7.3%, 6.3% and 1.2%, respectively). Compared with HL-60 and HL-60/pc cells, HL-60/CYP3A5 cells were statistically significantly resistant to daunorubicin, aclacinomycin A, vincristine and harringtonine (resistance multiples were 2.89, 2.01, 4.05 and 2.79 times, respectively, P < 0.05), however the sensitivity to teniposide didn't change (resistance multiple was 1.04 times).


CONCLUSIONS
Transcription of CYP3A5 gene in leukemia cells directly induces resistance to anthracyclines and alkaloids, however the cells are still sensitive to epipodophyllotoxins. Therefore, our findings confirmed a new mechanism of multidrug resistance.
Wang
Ting
T
Department of Hematology, Renji Hospital of Shanghai Second Medical University, Shanghai Institute of Hematology, Shanghai 200001, China.
Chen
Fang-yuan
FY
Gu
Chun-hong
CH
Zhong
Hua
H
Teng
Ye
Y
Ouyang
Ren-rong
RR
D015250:Aclarubicin / Q000494:pharmacology; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D051544:Cytochrome P-450 CYP3A; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D003630:Daunorubicin / Q000494:pharmacology; D018432:Drug Resistance, Multiple / Q000235:genetics*; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D018922:HL-60 Cells; D006801:Humans; D010641:Phenotype; D010957:Plasmids / Q000235:genetics; D011995:Recombination, Genetic; D014162:Transfection; D014750:Vincristine / Q000494:pharmacology
D000903:Antibiotics, Antineoplastic; D014750:Vincristine; D015250:Aclarubicin; D003577:Cytochrome P-450 Enzyme System; C510164:CYP3A5 protein, human; D051544:Cytochrome P-450 CYP3A; D003630:Daunorubicin