Andrographolide Induces Apoptosis of C6 Glioma Cells via the ERK-p53-Caspase 7-PARP Pathway

Figure 4

Effect of p53 siRNA on AND-induced apoptosis in C6 glioma cells. (a) Knockdown efficiency. Cells were transfected with p53 siRNA for 48 h, and cell lysates were analyzed for total p53 expression. 𝑁=3. ^∗∗𝑃<0.01, as compared to the siRNA-negative (siN) group. ((b)-(c)) Effect of p53 siRNA on AND-induced apoptosis. The cells were transfected with siN and siRNA-p53 (siP53) for 48 h and were then treated with 0.01% DMSO or 15 μM AND for 12 h and stained with DAPI (b), and the ratio of apoptotic cells counted (c). 𝑁=5. Bar = 20 μm. ^∗∗𝑃<0.01, compared to the siN + DMSO group. ^##𝑃<0.01 compared to the siN + AND group. (d) Cells were transfected with siN or siP53 for 48 h and then treated with 0.01% DMSO or 15 μM AND. Cell lysates were analyzed for c-PARP and c-caspase 7. 𝑁=3. ^∗𝑃<0.05, ^∗∗𝑃<0.01, as compared to the siN + DMSO. ^#𝑃<0.05, ^##𝑃<0.01, compared to the siN + AND group.

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