Figure 8

Modulation of 5'-AMP-activated protein kinase (AMPK; a metabolic energy sensor or cellular fuel gauge) pathway either up-regulates or down-regulates the activity of -575 p27 (p27-5'UTR). The estrogen receptor (ER)-negative MDA-MB-231 cells were transfected with -575 p27 (p27-5'UTR) and then exposed to D-(+)-glucose (20 mM), rotenone (20 μM), or AICA riboside (50 μM), compound C (1.25 μM) or metformin (3.02 μM) for 24 hours. The basal culture medium (DMEM) contained 1 g/L (or 5.55 mM) rather than the usual 4.5 g/L (or 25 mM) of D-(+)-glucose. All assays were performed in triplicates and the transfection experiments were repeated three times.