Fig. 4.

HSP90α is overexpressed in human and murine PKD-associated kidney cysts. (A) Quantification of expression levels of HSP90α determined from Western analysis; n = 5–8 for each group. (B and C) Immunohistochemical analysis of HSP90α expression in epithelial cells lining dilated tubules and cysts in kidneys from mice of indicated genotypes (B) with quantification index (C); n = 5 for each group. (D and E) Immunohistochemical analysis of HSP90α expression in human kidney tissue from PKD patients (D), with quantification index (E); n = 6–7 for each group. (F) Quantification of expression levels of HSP70 determined from Western analysis; n = 5–8 for each group. (G) Association between cyst volume and HSP70 expression. Dots represent individual mice of the indicated treatment groups. P < 0.001. (H) Ratio of kidney to plasma concentration of STA-2842 12 and 48 h after a single dose of STA-2842 (75 mg/kg) in 5-mo-old female Pkd1^−/− and control mice. n = 3 WT mice; n = 5–6 Pkd1^−/− mice. *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.005; n/s, not significant. Data are expressed as mean ± SEM. (Scale bars, 100 μm.)