Elevated concentrations of the small stress protein HSP27 in rat renal tumors.
The expression of two small stress proteins, alpha B crystallin and the 27-kDa heat shock protein (HSP27), was studied quantitatively and immunohistochemically in normal kidney and renal tumors in rats. Levels of alpha B crystallin in renal cell tumors tended to be higher than in normal kidney (P = 0.07), but with a wide range of values, whereas they were significantly lower in mesenchymal tumors (P < 0.0001). In contrast, HSP27 concentrations in both renal cell (mean +/- SD: 1790 +/- 940 ng/mg protein, n = 15) and mesenchymal (1260 +/- 1080 ng/mg protein, n = 10) tumors were significantly higher than the normal kidney value (142 +/- 30 ng/mg protein, n = 10, P < 0.0001). A positive correlation was found between alpha B crystallin and HSP27 levels limited to the renal cell tumor case (Pearson's correlation coefficient, r = 0.68, P < 0.01). Immunohistochemistry revealed the loops of Henle to be positive for alpha B crystallin, whereas HSP27 staining was positive in glomerular and interstitial vascular walls and epithelial cells of proximal and distal tubules. Positive immunostaining for alpha B crystallin was demonstrated in six of nine renal cell tumors (67%) studied and for HSP27 in all of the nine cases (100%).
Takashi
M
M
Department of Urology, Nagoya University School of Medicine, Japan.
Sakata
T
T
Ohmura
M
M
Kato
K
K
D000818:Animals; D002292:Carcinoma, Renal Cell / Q000378:metabolism*; D003459:Crystallins / Q000032:analysis; D006360:Heat-Shock Proteins / Q000032:analysis / Q000378:metabolism*; D007150:Immunohistochemistry; D007668:Kidney / Q000737:chemistry / Q000378:metabolism; D007680:Kidney Neoplasms / Q000378:metabolism*; D008297:Male; D008648:Mesoderm / Q000378:metabolism; D018832:Molecular Chaperones / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000378:metabolism*
D003459:Crystallins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones