Figure 1. Effects of DS2 on the growth of human cancer cells.

(A) Chemical structures of oridonin (1) and DS2 (2). (B) 6 × 10³ MGC-803, PC-3, EC9706 and EC109 cells were plated in 96-well culture plates. 24 hours later, the cells were changed with fresh medium and treated with DS2 or oridonin at the indicated doses for 24 hours or 48 hours, 0.1% DMSO was used as controls. Cell viability was measured by MTT assay. Data are mean ± SD (n = 3).