Figure 8. Effects of HIF1α knockdown and of parthenolide on the normoxic and hypoxic expression of the pro-inflammatory phenotype and HO1 transcription in DU145 cells.

A HIF1α shRNA cells were exposed to 1% O₂ or left untreated from 2 up to 72 h in the presence and absence of 5 µM parthenolide. mRNA levels for VEGF, RAGE, PTX3, COX2 and CXCR4 were analyzed by real-time PCR and normalized to the housekeeping gene 18S rRNA. For each gene we present the result on the time point where hypoxia exerted a maximum increase in transcription. Graphs show the ratio between the expression of parthenolide, hypoxia, parthenolide and hypoxia treated HIF1α shRNA cells with respect to the mean normoxic control of wt cell cultures (set at 1). Mean values ± SE. ° HIF1α shRNA normoxic control cells vs wt normoxic control cells, * hypoxic HIF1α shRNA cells vs HIF1α shRNA normoxic control cells. # Parthenolide treated hypoxic HIF1α shRNA cells vs hypoxic HIF1α shRNA cells. B Effect of parthenolide on the transcription the anti-inflammatory gene HO1 in HIF1α shRNA cells in normoxia and in hypoxia after 4 h (when parthenolide maximally upregulated HO1 expression in normoxic cultures) and 24 h treatment. Graph shows the ratio between the expression of parthenolide, hypoxia, parthenolide and hypoxia treated HIF1α shRNA cells with respect to the mean normoxic control of wt cell cultures (set at 1). Mean values ± SE. * Normoxic and hypoxic parthenolide treated HIF1α shRNA cells vs HIF1α shRNA normoxic control cells. C: control normoxic untreated cells. P: parthenolide treated cells. H: hypoxic cells. HP: parthenolide treated hypoxic cells.