[Inducible expression of hypoxia-inducible factor 1alpha on the proliferation and invasion property of HepG2 cells under normoxia in vitro].

Objective: To study the inducible expression of hypoxia-inducible factor 1alpha (HIF-1alpha) on the proliferation and invasion property of HepG2 cells under normoxia in vitro.
Methods: Constructed the HepG2(Tet-on-HIF-1alpha) cell line which could induce the expression of HIF-1alpha by doxycycline; Under normoxia in vitro, MTT assay was used to observe the proliferative and adhesive activity of cells, and the invasive activity was determined by transwell cell culture chamber method.
Results: Under normoxia, the HIF-1alpha mRNA and protein of HepG2(Tet-on-HIF-1alpha) cells could be induced up to (5.899 +/- 2.176) and (2.179 +/- 0.742) folds by doxycycline (1 microg/ml); There were no difference of A(490 nm) between the Dox(+)and Dox(-) group in experiment detecting the proliferation activity (P > 0.05); But in adhesive experiment, the A(490 nm) of Dox (+) group was 0.662 +/- 0.058, higher than the Dox(-) group 0.526 +/- 0.808 (P = 0.008); The invasive cell number of Dox(+) group was 37.611 +/- 8.424, but in the Dox(-) group, the number was 25.333 +/- 8.117 (P < 0.01).
Conclusions: Under normoxia in vitro, the Tet-on gene regulate system could increase the HIF-1alpha protein by inducing the HIF-1alpha mRNA; HIF-1alpha has no influence with the proliferation activity, but it could enhance the adhesive and invasive properties of HepG2 cells.