Over-expression of Hypoxia-inducible factor 1alpha increases invasive potency of LNCaP cells in vitro

Objective: To evaluate the effect of hypoxia-inducible factor-1α (HIF1α) overexpression on the invasive potency of human prostate cancer cell. Methods: Human prostate cancer cell of the line LNCaP were cultured and transfected by the recombinant plasmid pcDNA3. 1 (-)-HIF-1α containing the gene HIF1α with Lipofectamine 2000 system. The positive clone cells were selected by G418 and confirmed by Western blotting and immunofluorescence staining (LNCaP/ HIF1α cells). Transwell chambers with polycarbonate filter were coated by 100 μl Matrigel at 1:20 dilution in serum-free medium. LNCaP cell suspension and LNCaP/ HIF1α cell suspension were inoculated into the Transwell chambers respectively for 24 hours to analyze the invasive potency. Western blotting was used to detect the expression of E-cadherin, vimentin, matrix metalloproteinase-2 (MMP-2), cathepsin D, and urokinase-type plasminogen activator receptor (uPAR). Results: The expression level of HIF1α in the LNCaP/HIF1α cells was distinctly higher than that in the LNCaP cells. The numbers of LNCaP-HIF1α cells penetrating through the Transwell polycarbonate filter was 4.6 ± 0.4 × 10⁴, significantly higher than that of the LNCaP cells (3.2 ± 0.3 × 10⁴, P < 0.01). The expressions of vimentn, MMP-2, cathepsin D, and uPAR were all up-regulated in LNCaP-HIF1α cells than those of the LNCaP cells. Whereas, the expression of E-cadherin was down-regulated in the LNCaP-HIF1α cells. Conclusion: Over-expression of HIF-1α stimulates the invasion potency of human prostate carcinoma cell. The expression of E-cadherin, vimentin, MMP-2, cathepsin D, and uPAR, all playing an established role in the invasion of tumor, can be regulated by HIF-1 in human prostate cancer cell.