3,3′-Diindolylmethane: A Promising Sensitizer of γ-Irradiation

Figure 3

Effect of DIM on cells apoptosis. (a) Representative analyses of apoptotic MCF-7 cells by annexin V-FITC staining and flow cytometry at 48 h after they were treated with vehicle, DIM/γ-irradiation alone, and DIM plus γ-irradiation; (b) DNA fragmentation of MCF-7 breast cancer cells treated by DIM or/and γ-irradiation by TUNEL assay; (c) effects of DIM on the caspase-3 activity. DIM pretreated (20 μM, 2 h) before exposure to γ-irradiation (10 Gy) can significantly increase caspase-3 activity; (d) effect of DIM (20 μM) or γ-irradiation (10 Gy) treatment on activation of PARP cleavage. Whole cell lysates were analyzed by immunoblot analysis. Equal loading was confirmed by reprobing for β-actin.

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