Figure 5.
Increased Notch receptor and Notch ligand expression in breast cancer cells by hypoxia. (A) Western blot analysis of the expression of NOTCH3 in breast cancer cells under 21% O2 or 1% O2 culture conditions with or without GSI treatment. H, hypoxia; N, normoxia. (B) Expression of Notch ligands JAGGED1 and JAGGED2 in breast cancer cells under hypoxia. *P<0.01. (C) Expression of Notch ligand DELTA1 in breast cancer cells under hypoxia. *P<0.05; **P<0.01. (D) MCF7 cells were transfected with HES1-luc and TK-Renilla luciferase reporter genes and were cultured at 21% or 1% O2 conditions. Dual-luciferase assays were performed 48 h after transfection. *P<0.05; H, hypoxia; N, normoxia.