Biological effects of bortezomib in prostate cancer tissues. A and B, cytoplasmic and nuclear NF-κB were quantified using immunohistochemistry as described in Materials and Methods. NF-κB cytoplasmic expression is increased in patients treated with bortezomib (B), whereas nuclear expression is decreased compared with controls (A). Boxplot shows the median. C, apoptotic rate and proliferative index were determined as described in Materials and Methods. Results for patients treated with bortezomib and controls are shown. Boxplot shows the median. D, proliferative index in tumors of patients treated with bortezomib (1) compared with their matched preoperative biopsies (0). Note that all patients, except 2, have increase in the proliferation index. One had no change and one decreased.