[Interference of HIF-1alpha by RNA reduces the expression of matrix metalloproteinase-2 in human cervical carcinoma HeLa cells].
OBJECTIVE
Hypoxia inducible factor-1 alpha (HIF-1alpha) is a hypoxia-responsive factor, which commonly exists in the tissues of solid tumors. It plays crucial roles in maintaining cell energy metabolism, tumor angiogenesis and metastasis, cell proliferation and apoptosis. This study was to investigate the effect of silencing HIF-1alpha by RNA interference on the expression of matrix metalloproteinase-2 (MMP-2) in human cervical carcinoma HeLa cells, and to further explore the mechanism.


METHODS
Fifteen nude mice were divided into three groups randomly, and were inoculated with HeLa cells, pGenesil-1-HeLa cells and HIF-1alpha-HeLa cells, respectively. Expressions of HIF-1alpha, E-cadherin, beta-catenin, MMP-2 in the xenograft tumors of nude mice were detected by immunohistochemistry. pGenesil-1-HeLa or HIF-1alpha-HeLa cells were cultured under a hypoxic(1% O2) or normoxic environment for 48 h, while HeLa cells were cultured under the same condition as control. Expressions of HIF-1alpha, E-cadherin, beta-catenin and MMP-2 were measured by Western blot.


RESULTS
In HeLa, pGenesil-1-HeLa and HIF-1alpha-HeLa cell xenograft groups, the positive rates of HIF-1alpha protein were (69.0+/-12.1)%, (62.8+/-12.3)% and (17.4+/-8.8)%, respectively; expressions of E-cadherin were 1.00+/-0.07, 1.00+/-0.10, 3.21+/-0.25; expressions of beta-catenin were 4.21+/-0.92, 4.31+/-0.87, 1.29+/-0.72; and expressions of MMP-2 were 4.84+/-0.67, 4.50+/-0.71 and 1.00+/-0.83. HIF-1alpha and MMP-2 were positively correlated (correlation coefficient=0.521). Expressions of HIF-1alpha, beta-catenin and MMP-2 protein were low and that of E-cadherin protein was high in HIF-1alpha-HeLa cells under hypoxia or normoxia for 48 h; while opposite results were obtained in HeLa and pGenesil-1-HeLa cells.


CONCLUSIONS
Inhibition of HIF-1alpha could effectively down-regulate the expression of MMP-2 in human cervical carcinoma Hela cells.
Cancer Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China.
Tao
T
Xie
Xiang-Lin
XL
Yuan
Shi-Ying
SY
Yu
Bin
B
Yang
Lan-Lan
LL
Dong
D000818:Animals; D015820:Cadherins / Q000032:analysis; D005260:Female; D006367:HeLa Cells; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D007150:Immunohistochemistry; D020778:Matrix Metalloproteinase 2 / Q000032:analysis*; D051379:Mice; D008807:Mice, Inbred BALB C; D034622:RNA Interference; D051176:beta Catenin / Q000032:analysis
C495270:CTNNB1 protein, human; D015820:Cadherins; C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D051176:beta Catenin; D020778:Matrix Metalloproteinase 2