BSO treatment inhibits mitotic clonal expansion.

<p>A: Confluent 3T3-L1 cells were treated with 100 µM BSO. After 2 days cells were induced to differentiate. BSO treatment was renewed with every change of medium. Cells were counted at induction and at day 3 of differentiation using a hemocytometer. Cell number did not differ at induction of differentiation. B: Confluent cells were treated with 100 µM BSO for two days. Cells were labeled with CFSE and induced to differentiate. BSO treatment was renewed with every change of medium. On day 3 of differentiation cells were collected and analyzed using FACS. CFSE mean fluorescence declines with cell division, and geometric mean fluorescence is inversely proportional to the proliferation rate. C: Cells were treated as described in A. 24 h after induction of differentiation cell cycle distribution was assessed by DNA staining with propidium iodide and subsequent FACS analysis. Cell cycle distribution did not differ at induction of differentiation (baseline). D: Confluent subcutaneous stromal vascular cells were treated with 10 µM BSO. After 2 days, BSO treatment was renewed and cells were induced to differentiate. Cell cycle distribution was analyzed after 16 h. All results are presented as mean ± SEM (* p<0.05 vs. control).