Research Article

Mitogenic Effects of Phosphatidylcholine Nanoparticles on MCF-7 Breast Cancer Cells

Figure 2

ERK1/2 and MEK1/2 phosphorylation and protein content. MCF-7 breast cancer cells were incubated for 24 hs with PC nanoparticles dispersed at 0.01 and 0.01% (w/v) in buffer pH 5.0 and buffer pH 7.0 or vehicle (Ct) in absence ((a) and (c)) or presence ((b) and (d)) of serum. Representative results of immunoblots with anti-p44/42 MAP kinase (ERK1/2) and anti-phospho-p44/42 MAP kinase Thr202/Tyr204 ((a) and (b)) and anti-MEK1/2 and antiphospho MEK ((c) and (d)) are shown. Reprobing with anti-actin antibody demonstrated uniformity of protein loading in all lanes. Quantification of phosphorylated proteins was performed by scanning densitometry and expressed as percent of values measured for control, nonstimulated breast cancer cells (Ct). Data are expressed as the mean ± S.E.M. of the indicated number ( ) of different experiments. Statistical analysis was performed by ANOVA. Different letters denote significant difference at , whereas results with the same letter are not statistically different from each other.