[Value of MN/CAIX in the diagnosis of renal cell carcinoma]

To investigate the expression of MN/CAIX in patients with renal cell carcinoma (RCC) and assess the value of MN/CAIX in the diagnosis of RCC.

RT-PCR was employed to detect MN/CAIX mRNA in the carcinoma tissue and peripheral blood of 62 patients with RCC, using normal renal tissue and peripheral blood sample from 32 patients without RCC as control. Immunohistochemistry was used to detect MN/CAIX protein in the tissue specimens of clear cell RCC (n=36), non-clear cell renal neoplasm (n=17) and normal kidney (n=16).

The positivity rate of MN/CAIX mRNA was 82.3% (51/62) in renal carcinoma tissues and 54.8% (34/62) in the peripheral blood from patients with RCC, significantly higher than the rates in the control cases (P<0.05). In cases of clear cell renal cell carcinoma, the positivity rate of MN/CAIX mRNA was 98% (49/50) in the carcinoma tissues and 66% (33/50) in the peripheral blood, significantly higher than the rates in cases of non-clear cell type of RCC (P<0.05). Immunohistochemistry showed a significantly higher positivity rate of MN/CAIX protein in clear cell RCC tissues [97.2% (35/36)] than in non-clear cell renal neoplasm and normal renal tissues (P<0.05).

MN/CAIX is specifically overexpressed in RCC, especially in clear cell RCC, suggesting its potential in the diagnosis and prognostic and therapeutic evaluation of RCC.