Fig. 4

Promoter activities of Per2 and Bik under MTX treatment. Synovial fibroblasts transfected with vectors containing various Per2 or Bik promoters for 24 h. After treatment with MTX (10, 100 nM) or control media for 24 h, luciferase reporter assay was performed. Promoter activities of MTX-untreated cells defined as 1.0, and each value shown relative to control. Values are mean ± SEM. *p < 0.05, #p < 0.1, n = 5 (Per2), n = 6 (Bik). Bik Bcl-2 interacting killer, MTX methotrexate, Per period