Figure 1.

(a) myc-CaP cells derived from the FVB background were provided by C Sawyers (University of California, Los Angeles and Memorial Sloan Kettering Cancer Center).³ Virus-containing supernatants were added to the cells for 2 days with polybrene, and transduced cells were selected in 5 μg/ml puromycin (Invitrogen, Carlsbad, CA, USA). Male FVB mice were injected with myc-CaP cells, previously infected with lentiviruses expressing control (Scrambled) or BAG3-specific siRNAs. When tumors reached 900 mm³, mice (n=10 per group) were castrated. Tumor size was measured every 2–3 days. Results are expressed as means±S.D. Data were analyzed by Student's t-test using GraphPad Prism statistical program (^*P<0.001). (b) Paraffin sections of tumors transduced with BAG3 siRNA (right panel) or control vector (left panel) as described in a were stained using a specific antibody recognizing IKKα (Imgenex, San Diego, CA, USA) and counterstained with hematoxylin as previously described³ (original magnification × 200). (c) myc-CaP cells were infected with a lentivirus carrying a control (Scrambled; left panel) or a BAG3-specific siRNA (right panel) then treated with LTα2β1, TGFβ or RANKL, all at 10 ng/ml (Sigma, Aldrich, St. Louis, MO, USA) for 1 h. Cells were harvested and subjected to nuclei/cytosol fractionation. Lysates were analyzed by immunoblot, using the same antibody as in b (C, cytosol; N, nucleus).