[Effects of hypoxia-inducible factor inhibitor on expression of HIF-1alpha and VEGF and induction of apoptosis in leukemic cell lines].
This study was purposed to investigate the effect of a hypoxia-inducible factor inhibitor (YC-1) on expression of hypoxia-inducible factor 1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) as well as induction of apoptosis in leukemic cell lines. RT-PCR was used to determine the levels of HIF-1alpha mRNA and VEGF mRNA in K562, U937 and Jurkat cells. After treatment of U937 cell with 4 micromol/L YC-1, cell apoptosis was assayed by DAPI staining under fluorescent microscope and flow cytometry with Annexin V-FITC/PI staining; the expression levels of HIF-1alpha mRNA and VEGF mRNA were measured with RT-PCR; the expression levels of HIF-1alpha, VEGF, BAX, BCL-2 and caspase-3 proteins were measured by Western blot. The results showed that HIF-1alpha mRNA and VEGF mRNA were expressed in all three leukemia cell lines. After treatment of U937 cell with 4 micromol/L YC-1 for 0, 8, 16 and 24 hours, the changes of morphologic features of U937 cells could be observed under fluorescent microscope and the apoptotic rates significantly increased in time-dependent manner, they were (4.87 +/- 0.70)%, (27.27 +/- 2.00)%, (51.53 +/- 2.81) and (60.5 +/- 3.20)% respectively, the expression levels of VEGF mRNA reduced, while the expression levels of HIF-1alpha mRNA had no obviously changes.Furthermore, the expression of HIF-1alpha, VEGF and BCL-2 decreased, while the expression of BAX and caspase-3 increased, the ratio of BAX/BCL-2 increased in time-dependent manner (r = 0.973, p < 0.01). It is concluded that HIF-1alpha mRNA and VEGF mRNA are all expressed in in K562, U937 and Jurkat cells, YC-1 has significant effect on down-regulating the protein expression of HIF-1alpha and VEGF, and induces the apoptosis in U937. The mechanism of apoptosis in leukemic cells may involve in up-regulating BAX/BCL-2 ratio and expression of protein caspase-3.
Wang
Fei
F
Department of Hematology, Zhongda Hospital, Southeast University Clinical Medical College, Nanjing 210009, Jiangsu Province, China.
Chen
Bao-An
BA
Cheng
Jian
J
Xu
Wen-Lin
WL
Wang
Xue-Mei
XM
Ding
Jia-Hua
JH
Gao
Chong
C
Sun
Yun-Yu
YY
Wang
Jun
J
Zhao
Gang
G
Bao
Wen
W
Song
Hui-Hui
HH
Gao
Feng
F
Zhang
Wei
W
Xia
Guo-Hua
GH
Pei
Xiao-Ping
XP
Wu
Wei-Wei
WW
Yin
Li
L
Shan
Xue-Yun
XY
D017209:Apoptosis / Q000187:drug effects*; D015687:Cell Hypoxia; D015973:Gene Expression Regulation, Leukemic; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D007191:Indazoles / Q000494:pharmacology*; D019169:Jurkat Cells; D020014:K562 Cells; D020298:U937 Cells; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D007191:Indazoles; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C090937:3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole