Figure 5

Functional analysis of MDA sublines. (A)Two parametric BrdU/Hoe33258 (Fl-IV) versus EtBr (Fl-III) fluorescence density plots of MDA-MB-468 CD44+/CD24 -/LOW cells displayed clearly a higher proliferation rate of low (I) EGFR expressing cells (n = 3; mean R1/R2 = 32%/68%) when compared with high (II) EGFR expressing cells (n = 3; mean R1/R2 = 41%/59%). (B) Western blot analysis of erk 1/2 (p44/p42 MAP - Kinase), phospho-erk (Thr202/Tyr204), Akt and phospho-Akt (Ser473) in MDA-MB-468 CD44+/CD24 -/LOW high (lanes 1 - 3), MDA-MB-468 CD44+/CD24 -/LOW low (lanes 4 - 6), and SK-BR-3 (lanes 7 - 9). Lanes 1, 4, and 7 represent protein expression of cells cultured in DMEM medium supplemented with 5% FCS; proteins in lanes 2, 5, and 8 are from cells cultured under 0.1% FCS for 24 h; and proteins in lanes 3, 6, and 9 are from cells stimulated with EGF (100 nM) for 30 minutes after FCS starvation for 24 h. For quantitative evaluation of western blot analysis see, Additional file 1.