Inhibition of RAD51 by siRNA and Resveratrol Sensitizes Cancer Stem Cells Derived from HeLa Cell Cultures to Apoptosis

Figure 6

Resveratrol inhibits RAD51 expression in sphere cultures. (a) VP16 in the presence of RESveratrol (RES) decreases cell viability in HeLa SPhere (SP) cultures. Culture was exposed 72 h to both 5.8 μg/mL VP16 and 137 μM RES. Under these conditions, cell viability measured by MTT assay was strongly decreased (to 15.3%). Ethanol was used as vehicle control. (b) Western blot analysis shows that RES (137 μM) treatment for 48 h inhibited RAD51 protein expression (similar to siRAD51) in SP cultures as compared to HeLa SP without treatment or HeLa SP treated with Etoposide. RAD51 protein levels were highly reduced when HeLa SP were treated with resveratrol alone or together with Etoposide. Untreated MonoLayer (ML) HeLa cells were also used as a control.

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