Figure 3. Gomisin M2 suppresses CSC self-renewal. (A) MDA-MB-231 cells were treated with 20 μM or 40 μM Gomisin M2 or DMSO control for 48 h. In the absence of Gomisin M2, the first and second passages that were derived from Gomisin M2-treated primary tumor spheres produced a smaller number of spheres compared with the DMSO control. (B) HCC1806 cells were treated with 30 μM or 60 μM Gomisin M2 or DMSO control for 48 h. The same method was applied to HCC1806 cells. Right panel, the number of two-passage spheres compared with the control. The data are presented as the mean ± SD. **, P<0.01.