FIG 5.
Calpain knockdown enhances 17AAG-induced downregulation of HSP90 clients in vivo. Mice were engrafted with MDA-MB-231 cells transduced with control or calpain knockdown shRNA-Capns1-expressing lentiviruses. When tumors reached 100 to 200 mm3, mice were treated with the vehicle or 75 mg/kg 17AAG for 3, 6, or 12 h in duplicate. (A) Mice were euthanized, and tumors were excised for immunoblotting analysis of the proteins indicated. (B to E) Densitometric quantitation of cyclin D1 (B), AKT (C), pERK (D), and HSP90 (E) is shown. *, P ≤ 0.05 by Student's t test. AU, arbitrary units.