Fig. 7.

Palbociclib combined with the PI3K/AKT inhibitor BYL719 hinders glucose metabolism under normoxic and hypoxic conditions. MDA-MB-231 cells were treated with 0.5 μM palbociclib and 5 μM BYL719 alone or in combination under normoxic or hypoxic (1% O₂) conditions for 24 h. Glucose uptake (a) and glucose consumption (b) were measured. *p < 0.05, **p < 0.01, ***p < 0.001 vs ctrl Normoxia (N); ^●p < 0.05, ^●●p < 0.01 vs palb N; ^▪p < 0.05, ^▪▪p < 0.01 vs BYL N; ^##p < 0.01, ^###p < 0.001 vs ctrl Hypoxia (H); ^§§p < 0.01 vs Palb H; ^$$$p < 0.001 vs BYL H. c The expression of the indicated proteins was analyzed by Western blotting. d GLUT-1 mRNA levels were analyzed by RT-PCR. Results are plotted as 2^-ΔΔCT ± SD. e MDA-MB-231 cells were treated with 0.5 μM palbociclib for 48 h and 5 μM BYL719 for 24 h alone or were pre-incubated with palbocilcib for 24 h and then with palbociclib combined with BYL719 for further 24 h. Glucose uptake was then evaluated. **p < 0.01, ***p < 0.001 vs ctrl; ^###p < 0.001 vs palb; ^§§§p < 0.001 vs BYL. f The cells were treated as in e and GLUT-1 expression was evaluated by Western blotting on cell protein extracts. Data in a,b and e are mean values ±SD of three independent experiments (n = 6). Data in d are mean values ±SD of three independent experiments (n = 4). Results in c and f are representative of two independent experiments