The PDGF pathway regulates proliferation of Luminal MCF-7 cells
. A. MCF-7 cells in 2D on plastic were incubated with control or BJ3Z cell-conditioned media (CM) in the absence or presence of Imatinib Mesylate (IM). Percent of cells incorporating BrdU were compared to total cells (DAPI) to quantify proliferation; n = 3, *p < 0,05 by ANOVA followed by Tukey’s post-test. B. MCF-7 cells in 3D Matrigel monoculture, or co-cultured with BJ3Z cells, were treated with IM for 48 hr. BrdU incorporation (green nuclei) into MCF-7 cells was used to quantify proliferation compared to total cells (DAPI; blue nuclei). Cytokeratin-18 (red)-positivity mark the Luminal MCF-7 cells; BJ3Z cells are CK18-negative; n = 3; bar denotes 100 μm. Quantification of data is on the right with *p < 0,05 by ANOVA followed by Tukey’s post-test. C. MCF-7 cells in 3D Matrigel colonies were treated with recombinant PDGF-BB, 30 ng/ml for 48 hr. Phosphorylated-Histone H3 expression was quantified by IHC, n = 3, bar: 100 μm. *p < 0,05 by Student’s t-test. D Proliferation in PDGF-BB treated MCF-7 cells was quantified by BrdU incorporation, n = 3, *p < 0,05 by Student’s t-test.