[Expression of hypoxia inducible factor-1alpha and glucose transporter protein 1 in renal and bladder cancers and the clinical significance thereof].

OBJECTIVE

To investigate the protein expression of hypoxia inducible factor-1alpha (HIF-1alpha) and glucose transporter protein 1 (Glut-1) in renal cancer and bladder cancers and the clinical significance thereof.

METHODS

TransAMTMELISA was used to detect the protein expression of HIF-1alpha in the tissue sections from 25 patients with bladder transitional cell carcinoma (TCC) and 16 patients with renal clear cell carcinoma resected during operation and small amounts of normal renal and bladder tissues far from the cancer tissue resected simultaneously. Immunohistochemistry was used to detect the protein expression of Glut-1 in tissue sections from 58 patients with bladder carcinoma transitional cell carcinoma and 38 patients with renal clear cell carcinoma resected during operation. 16 specimens of normal bladder and 16 specimens of normal renal tissue were obtained from the patients with other diseases who underwent operation during the same period to be used as controls. Follow-up was conducted for more than 2 years for all patients.

RESULTS

The protein expression of HIF-1alpha in the tissue of renal clear cell carcinoma was 3.38 +/- 1.71 microg/well, significantly higher than that in the tissue near the cancer (2.23 +/- 1.07 microg/well, P < 0.01). The protein expression of HIF-1alpha in the bladder TCC tissue was 2.69 +/- 1.34 microg/well, not significantly different from that in the tissue near the cancer (248 +/- 1.28 microg/well, P = 0.60). Protein expression of Glut-1 was not detected in the normal renal and bladder tissues, however, was significantly higher in the bladder TCC and renal clear cell carcinoma tissues. The positive rate of Glut-1 in the bladder TCC tissue was 77.90% (45/58). The positive rates of Glut-1 in the tissues of bladder TCC tissue, grades G1, G2, and G3 were 66.7%, 89.1%, and 53.3%. (P = 0.29), showing the correlation of Glut-1 expression with the grading of cancer. The positive rate of Glut-1 in the superficial TCC was 83.9%, not significantly different from that of the invasive TVV (70.4%, P = 0.90), showing that the Glut-1 is not correlated with the cancer staging. Nineteen of the 31 cases of superficial TCC showed recurrence within 2 years, however, the protein expression of Glut-1 rate was not significantly different between those with recurrence and those without recurrence (P = 0.90), showing that the protein expression of Glut-1 is not correlated with the recurrence of TCC. The protein expression of Glut-1 in the renal clear cell carcinoma was at a rate of 86.9% (33/38), however, it was not correlated with the grade and stage of the cancer.

CONCLUSION

The protein expression of HIF-1alpha is strongly associated with the neoplastic progression of renal clear cell carcinoma, but its role in the development of bladder TCC is not clear yet. The protein expression of Glut-1 is strongly associated with the neoplastic progression of bladder TCC and renal clear cell carcinoma.