Manassantins inhibit hypoxic induction of HIF-1 target genes CDKN1A, GLUT-1, and VEGF in T47D cells. Quantitative real time RT-PCR analysis was performed to determine CDKN1A (A), GLUT-1 (B), and VEGF (C) mRNA levels following treatments with 1, 2, 4, and 6 (30 nM each) under hypoxic conditions (1% O2) for 16 h. "C" represents media only. Data shown are relative expression levels (mean ± SD) of target genes normalized to that of an internal 18S rRNA control, determined from one representative experiment performed in triplicate.