Figure 7. Reelin induced HIF1α upregulation through STAT3 and PI3K/Akt pathways.

(A) Reelin alters the protein levels of HIF1α and its targets. H929 cells were transfected with pCrl/vector or Reelin specific siRNAs/siNC for 40 hours. The cells were then cultured in FN-coated plates for 24 hours and were subjected to western blotting with HIF1α, PDK1, LDHA, and β-actin-specific antibodies. (B) The addition of Reelin protein abolished HIF1α down-regulation in cells with Reelin knockdown. H929 cells were transfected with Reelin-specific siRNA or control siRNA for 40 hours. The cells were then seeded in FN-coated plates with rReelin or BSA control. Twenty-four hours later, the cells were harvested and the cell lysates were subjected to western blotting. (C) PI3K/Akt is involved in Reelin-induced HIF1α upregulation. pCrl-transfected H929 cells were treated with DMSO or PI3K inhibitor LY 294002 for 24 hours. The cells were then subjected to western blotting. (D) STAT3 is involved in Reelin-induced HIF1α upregulation. H929 cells were co-transfected with pCrl and STAT3-specific siRNAs (or siNC) or pcDNA3 with siRNAs. The cells were then seeded in FN-coated plates for 24 hours and were subjected to western blotting.