Fig. 1

Direct co-culture of prostate carcinoma cells with MSCs significantly enhanced the stemness of prostate carcinoma cells. a Flow cytometry was employed to evaluate the subpopulation of CD133⁺ PC-3 cells in mono-culture, transwell-culture, and mixed co-culture with MSCs. b Clonogenic ability of the sorted PC-3 cells in each group was examined using clonogenic assay (in a conventional attachment six-well plate, 2 × 10³ cells/well, two weeks). The representative photographs are provided in the left panel (× 10), and quantified data of three independent experiments are shown in the right panel. c Cell sphere formation assay (in an ultra-low attachment six-well plate,5 × 10³ cells/well, seven days) was performed to examine tumor sphere formation in mono-culture, transwell-culture, and mixed co-culture of MSCs with PC-3 cells. Quantitation of sphere formation (left panel) and representative photographs of sphere size (right panel, × 40) are provided. d, e After multiple dilutions, the colony formation experiment (in a conventional attachment 96-well plate) and sphere formation assay (in an ultra-low attachment 96-well plate) of the PC-3 cells in each group was performed. f The expression of stemness-related molecules (Sox2, Oct4 and Nanog) was investigated by western blot analysis, with Lamin B1 was used as an internal reference. Quantification of image was presented as the mean ± SD; *P < 0.05, **P < 0.01; ***P < 0.001