Figure 2

Bone marrow-derived mesenchymal stem cells enhance breast and prostate cancer cell proliferation in vitro. (a) Luc-4T1 cells were co-cultured with mouse bone marrow-derived mesenchymal stem cells (mBM-MSCs), 4T1 cells or mouse skin fibroblasts and (b) Luc-DU145 cells were cultured with human bone marrow-derived mesenchymal stem cells (hBM-MSCs), DU145 cells or mouse skin fibroblasts at the ratio of 1:1. Luciferase activities were measured every 12 hours for a 72-hour period to determine growth of tumor cells in the co-culture assay (n = 6 per group; **P <0.01). (c) Luc-4T1 cells were incubated with mBM-MSCs and (d) Luc-DU145 cells were incubated with hBM-MSCs at different ratios. (e) Luc-4T1 cells were incubated with mouse skin fibroblasts and (f) Luc-DU145 cells were incubated with mouse skin fibroblasts at different ratios. Luciferase activities were measured after 48 hours (n = 6 per group; **P <0.01). (g) 4T1 cells were cultured in mBM-MSC conditioned medium and (h) DU145 cells were cultured in hBM-MSC conditioned medium for 72 hours. BrdU assay was performed to measure the proliferation of tumor cells at the indicated time points (n = 6 per group; *P <0.05, **P <0.01).