Figure 6. Representative Western blot and immuno­precipitation (IP) analyses of Ras proangiogenic targets (A) and inhibitors of Ras-driven angiogenesis (B).

Upregulation of HIF-1α, VEGF, and IL-8 (A) was associated with high HIF-1α/ARNT complexes, low levels of HIF-1α inhibitors (IGFBP3, BNIP3, BNIP3L, and EGLN2), and low EGLN2/HIF-1α complexes in subclass A HCC (B). (C) Suppression of Ras downstream effectors MEK (UO126 [UO]) and AKT (LY294002 [LY]) led to downregulation of HIF-1α, VEGF, and IL-8 in Focus hepatoma cell lines. (D) Reactivation of HIF-1α inhibitors and EGLN2 by Zebularine (Zeb) reduced HIF-1α, VEGF, and IL-8 expression in Focus hepatoma cell lines. Equivalent results were obtained in SNU-387 and 7703 hepatoma cell lines (data not shown).