Fig. 1

Proliferation activity of osteosarcoma cell lines after treatment with MTX. Proliferation activity was measured using MTT assay at day 6 of incubation with various concentrations of MTX and compared with those of untreated control cells. Untreated controls were set as 100 %. The data represent the mean ± SD. Experiments were repeated three times in duplicates. **P < 0.01, indicates significant differences from the respective cell lines