Figure 1.

5-fluorouracil (5-FU) inhibits the growth of both tumor cells and bone marrow stromal cells in a dose and time-dependent manner. Cell proliferation assay was performed via the Cell Counting Kit-8 kit. (a) Cell inhibition rates are presented as (OD_{control group} − OD_{experimental group})/OD_{control group} × 100%. MCF-7 treated without 5-FU was used as a control; (b) The inhibitory effects of 5-FU on HCT-16 cells are presented as inhibition rates: (OD_{control group} − OD_{experimental group})/OD_{control group} × 100%. HCT-16 treated without 5-FU was used as a control; (c) The cell viabilities of HS-5 were almost entirely decreased with tumor-suppressive doses of 5-FU. Viability rate = OD_{experimental group}/OD_{control group} ×100%. The cell viabilities of HS-5 without 5-FU treatment on each day were set as 100%. Results of HS-5 cell viability were normalized to the OD value of control HS-5; (d) Representative images of Fibroblast-colony forming unit (CFU-F) formed from 5-FU-treated and control HS-5 cells by phase contrast microscopy. CFU-F frequency decreased with increasing 5-FU doses (Scale bar = 50 μm). * p < 0.01 vs. control. CTL: Control; OD: optical density.