Methylating effect of daphnetin and 5-aza-dc on DR3, PDCD5, FasL and p53 in CIA rat synovial cells. Four experimental groups consisting of untreated cell control, or treated with 5-aza-dc at 20 μM, daphnetin at 40 μg/mL, or combination of 5-aza-dc (20 μM) and daphnetin (40 μg/mL). Cells were cultured, treated and harvested as described in Materials and Methods. Total DNA was extracted and used for MSP after bisulphite modification. M: methylated amplification products, U: hypomethylated amplification products.