Objective: To evaluate the effect of hypoxia-inducible factor-1alpha (HIF1alpha) over-expression on the invasive potency of human prostate cancer cell.
Methods: Human prostate cancer cells of the line LNCaP were cultured and transfected by the recombinant plasmid pcDNA3.1(-)-HIF-1alpha containing the gene HIF1alpha with Lipofectamine 2000 system. The positive clone cells were selected by G418 and confirmed by Western blotting and immunofluorescence staining (LNCaP/HIF1alpha cells). Transwell chambers with polycarbonate filter were coated by 100 microl Matrigel at 1:20 dilution in serum-free medium. LNCaP cell suspension and LNCaP/HIF1alpha 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 HIF1alpha in the LNCaP/HIF1alpha cells was distinctly higher than that in the LNCaP cells. The numbers of LNCaP-HIF1alpha cells penetrating through the Transwell polycarbonate filter was 4.6 +/- 0.4 x 10(4), significantly higher than that of the LNCaP cells (3.2 +/- 0.3 x 10(4), P < 0.01). The expressions of vimentin, MMP-2, cathepsin D, and uPAR were all up-regulated in LNCaP-HIF1alpha cells than those of the LNCaP cells. Whereas, the expression of E-cadherin was down-regulated in the LNCaP-HIF1alpha cells.
Conclusion: Over-expression of HIF-1alpha 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.