Fig. 1. Expression of HIF-1{alpha} is increased by the addition of insulin or with the mutation of PTEN in cancer cell lines. U2-OS, ACHN, DU145, AND PC-3 cells were cultured in serum-free MEM with Earle’s salts for 24 h, followed by incubation in the absence or presence of 200 nM insulin for 6 h. Nuclear extracts were prepared, and 10 µg of the nuclear extracts were used for immunoblot analysis and detected by antibodies against HIF-1{alpha} and HIF-1ß.