Na,K-adenosine triphosphatase alpha1-subunit predicts survival of renal clear cell carcinoma.
OBJECTIVE
Na,K-adenosine triphosphatase, which is composed of a catalytic alpha-subunit and a regulatory beta-subunit, generates an electrochemical gradient across the plasma membrane. Previous studies demonstrated altered Na,K-adenosine triphosphatase subunit expression in renal clear cell carcinoma and an association of subunit levels with the prediction of recurrent bladder cancer. We determined the clinical association of protein expression patterns of the Na,K-adenosine triphosphatase alpha1 and beta1-subunits in renal clear cell carcinoma using tissue microarrays with linked clinicopathological data.


METHODS
The UCLA kidney cancer tissue microarray was used to investigate the protein expression of Na,K-adenosine triphosphatase alpha1 and beta1-subunits by immunohistochemistry in 342 patients with renal clear cell carcinoma who were treated with radical nephrectomy. Of these patients clinical outcomes studies were performed in 317. The resultant expression reactivity was correlated with clinicopathological variables.


RESULTS
We found that the alpha1-subunit was a significant and independent predictor of disease specific death from renal clear cell carcinoma on multivariate Cox proportional hazards analysis that included established prognostic factors Eastern Cooperative Oncology Group performance status, pT status, metastasis status and tumor grade. Significance was found when examining all patients with clear cell renal cell carcinoma as well as patient substrata with low or high grade tumors and localized or metastatic disease, suggesting that the Na,K-adenosine triphosphatase alpha1-subunit could be used as a new prognosticator for disease specific death from renal clear cell carcinoma.


CONCLUSIONS
These results suggest that Na,K-adenosine triphosphatase alpha1-subunit expression patterns may be a useful clinical prognosticator for renal clear cell carcinoma. The Na,K-adenosine triphosphatase beta1-subunit was not found to be a useful prognosticator in this setting.
Seligson
David B
DB
Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, California, USA.
Rajasekaran
Sigrid A
SA
Yu
Hong
H
Liu
Xueli
X
Eeva
Mervi
M
Tze
Sheila
S
Ball
William
W
Horvath
Steve
S
deKernion
Jean B
JB
Rajasekaran
Ayyappan K
AK
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D002292:Carcinoma, Renal Cell / Q000201:enzymology* / Q000401:mortality*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000201:enzymology* / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D000254:Sodium-Potassium-Exchanging ATPase / Q000096:biosynthesis*; D015996:Survival Rate
D014408:Biomarkers, Tumor; D000254:Sodium-Potassium-Exchanging ATPase