EGCG neutralizes the antitumoral effects of BZM in multiple myeloma in vivo. Tumor-bearing mice were treated with bortezomib and EGCG individually or in combination, or remained untreated. Seventy-two hours later, the animals were killed and the tumors were analyzed by TUNEL (apoptosis indicator) or H&E (morphology). (A) Representative microphotographic images were taken of the TUNEL staining (original magnification 400× for all panels). Arrowheads indicate representatively selected TUNEL-positive cells. (B) The percentage of TUNEL-positive cells (reddish-brown stain) was determined in 10 randomly chosen microscopic fields from each treatment group. Columns represent mean; bars, SEM. Statistically significant differences in the extent of tumor cell death between individual and combination drug treatments are indicated in the chart. (C) Representative microphotographic images were taken of the H&E staining (original magnification ×200 for all panels). Open arrowheads indicate area of subcapsular necrosis.