Fig. 2

Luteolin inhibits progestin-induced secretion of VEGF from human breast cancer cells. a T47-D cells were treated at 37 °C for 18 h with 10 nM MPA, 10 nM MPA + 1 µM RU-486 (RU), 10 nM MPA + 2 or 10 µM luteolin (LU), 2 µM or 10 µM LU, or 1 µM RU-486. b T47-D cells were treated at 37 °C for 18 h with 10 nM MPA, progesterone (P4), norethindrone (NE), or norgestrel (NG) ± 10 µM LU, or 10 µM LU alone. c BT-474 cells were treated at 37 °C for 18 h with 10 nM MPA ± 10 or 25 µM LU, or 10 µM or 25 µM LU alone. Levels of VEGF in culture medium were measured by ELISA. In all experiments, LU or RU was administered 30 min prior to MPA. VEGF ELISA values were normalized to cellular protein content, measured using bicinchoninic acid protein assays. Results represent mean ± SEM (n = 3, in duplicate). *Significantly different from control (DMSO only) (P < 0.05, ANOVA). **Significantly different from progestin alone (P < 0.05, ANOVA)