Figure 1. Screening of 144 compounds from an in-house chemical library for inhibition of HIF-1 activity.

HEK-293 cells were co-transfected with luciferase reporter plasmids (pGL3-HRE-luciferase) and Renilla vector (pRL-SV40). Cells were exposed to hypoxic conditions in the presence or absence of chemicals for 24 h, and were then lysed for assays of luciferase activity. Echinomycin (E), a known HIF-1α inhibitor, was used as a positive control. N, normoxia, H, hypoxia. Three independent experiments were performed in triplicate.