常氧条件下调控表达缺氧诱导因子1α对肝癌细胞增殖和侵袭能力的影响

目的探讨在体外常氧条件下,诱导表达缺氧诱导因子1d（HIF-1α）对肝癌细胞（HepG2）增殖及侵袭能力的影响。方法利用Tet—on基因调控系统构建能诱导表达HIF-1α的HepG2^Tet-on-HIF-1α“细胞系;常氧条件下,噻唑兰法检测HIF-1α对细胞增殖、黏附能力的影响,Transwell法检测其对HepG2细胞侵袭能力的影响。结果常氧条件下,强力霉素（1μg／m1）可诱导HepG2^Tet-on-HIF-1α“细胞HIF-1αmRNA和蛋白表达增加;增殖实验中,Dox（＋）组与Dox（一）组各时段吸光度A490nm值无差异（P〉0．05）;黏附实验中,Dox（＋）组的A490nm值明显高于Dox（-）组（P=0．008）;Dox（＋）组侵袭细胞数[（37．6114-8．424）个]明显高于Dox（-）组[（25．3334-8．117）个]（P〈0．01）。结论Tet—on基因调控系统可上调HIF-1α mRNA的转录并增加其蛋白的表达;常氧条件下,HIF-1α不影响HepG2细胞的增殖,但明显增加其黏附和侵袭能力。

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 invasived 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.