Breast cancer cell lines stimulate MSC proliferation.

<p>MSCs were grown in the complete DMEM medium mixed with equal volume of RPMI 1640 media or with conditioned media of RCAS-Neu, RCAS-PyMT or NIH 3T3 cells for 48 hr. Cells were photographed (A) (left panel) and analyzed for cell proliferation by MTT assay (B) (right upper panel). (C) RCAS-Neu CM increases BrdU incorporation in MSCs. MSCs were grown in the complete DMEM medium mixed with equal volume of RPMI 1640 culture media or with conditioned media of RCAS-Neu cells for 48 hr. Cells were labeled with 10 µM BrdU overnight and then analyzed for BrdU incorporation by staining with an Alexa-488-conjugated anti-BrdU antibody. Alexa 488-conjugated mouse IgG was used as an isotype control.