[Analyzing anti-cancer action mechanisms of dihydroartemisinin using gene chip].
OBJECTIVE
To understand the action mechanisms of artesunate on inhibiting leukaemia cell line K562 on the molecular level.


METHODS
The gene chip was used to detect the expression panel of genes of leukaemia cell line K562 treated by dihydroartemisinin. K562 cells were treated with 1 x 10(-5), 4 x 10(-5), 16 x 10(-5), 64 x 10(-5), 256 x 10(-5) mol x L(-1) dihydroartemisinin for 24 h, and then studied the modality changes by invert microscope. The morphological changes of the nucleons were observed by Hoechst33342/PI staining. The cell cycle were examined by flow cytometry analysis (FCM). Total RNA samples were obtained by TRIzol and were reverse transcribed to the cDNA. The cDNA samples were hybridized to our gene chips. Hybridization signal were collected and analyzed following scanning by Gene Pix 4100A.


RESULTS
The numbers of drift cells were increased and the density of cells was decreased under invert microscope after K562 cells were treated with dihydroartemisinin for 24 h. Morphological changes of cell apoptosis such as karyopyknosis and conglomeration were observed by Hoechst 33342/PI staining. Flow cytometric analysis showed that cells were arrested in G2 phase. There were 13 differentially expressed genes identified. Hybridization analysis showed up-regulation of chk1 and down-regulation of PCNA, cyclinB1, cyclinD1, cyclinE1, cdk4, cdk2, E2F1, DNA-PK, DNA-Topo I, mcl-1, jNK, VEGF in the dihydroartemisinin-treated K562 cells.


CONCLUSIONS
Dihydroartemisinin can Inhibit the leukaemia cell line K562 and exert its anti-cancer effect by altering the expression of these genes involved in cell cycle; dihydroartemisinin may act via apoptosis pathway.
Department of Biochemistry, Medical College of the Chinese People's Armed Police Forces, Tianjin 300162, China.
Li
L
Yao
Hong
H
Xie
Qiu-Yue
QY
Jin
Wen-Liang
WL
Hu
Li-Jun
LJ
Chen
D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D037621:Artemisinins / Q000494:pharmacology*; D002452:Cell Count; D002453:Cell Cycle / Q000187:drug effects; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D020014:K562 Cells; D008853:Microscopy; D020411:Oligonucleotide Array Sequence Analysis; D012313:RNA / Q000032:analysis / Q000302:isolation & purification
D000970:Antineoplastic Agents; D037621:Artemisinins; D012313:RNA; C039060:artenimol