The Correlation Of Survivin With Micrometastases And PTEN In Renal Cell Carcinoma

Objective Survivin is a member of the inhibitor of apoptosis protein(IAP) family and is involved in both inhibition of apoptosis and regulation of cell division. Although rarely expressed in terminally differentiated normal adult tissues, Survivin is upregulated in most malignancies. Our study is attempt to examine the expression of Survivin in renal cell cancer , and to analyse the relationship with micrometastases and PTEN.Methods The protein expression of Survivin and PTEN were investigated by immunohistochemical PV technique in tissues from 50 cases of renal cell cancer and 10 normal renal tissues . Survivin mRNA positive cells were detected by RT - PCR in peripheral blood and fresh tissue samples which were collected from 30 eligible patients who had been received radical nephrectomy for the renal carcinoma.Results In 50 cases of renal cell cancer , the protein positive rates of Survivin and PTEN were 86% and 16% respectively ,while in normal renal tissue, the positive rates of Survivin and PTEN were 0 and 100%. The expression of Survivin in renal cell cancer was significantly higher than that in normal tissue( P< 0.001) . Eight cases (57. 1%) of Grade I , 19 (95%) of Grade Ⅱand 16(100%) of Grade Ⅲ were all positive for Survivin. Positivestaining was seen in 16(72. 7 %) of Stage I -11,27(96.4 %) of Stagelll— IV cases. Survivin positivity was correlated with the pathological grade (.P <0.05) and the clinical stage (P <0.05) .The expression of PTEN was significantly higher in normal tissue than in renal cell cancer( P< 0.001). Six cases (42. 9 %) of Grade 1,2 (10 %) of Grade II and 0(0%) of Grade IH were positive for PTEN. Positive staining was seen in 8(36.4%) of Stage I ~II, 0(0 %) of StageIII~ IV cases. The expression of PTEN was related to the pathological grade (P<0. 05) and the clinical stage (/><0. 05 ) . There was significant negative correlation between the expression degrees of Survivin and PTEN( P < 0.001) .The positive rate of Survivin mRNA in blood samples of 30 patients with renal cell cancer was 76. 7 % and there were significant differences compared with healthy volunteers (K0. 001) as well as 25 fresh-frozen tumor tissues (83.3 %) were detected Survivin mRNA. The expression of Survivin mRNA in blood samples and fresh-frozen tumor tissues were all related to the clinical stage( P <0. 01) . The positive rates were increased with the pathological grade but the expression of Survivin mRNA were not correlated with the pathological grade (P>0. 05) .Conclusions Survivin was overexpressed in renal cell cancer but PTEN was reduced. Survivin may play an promoting role and PTEN may play an postponement role in the development of renal cell cancer. Survivin and PTEN may have some relation with aggression and prognosis of renal cell cancer. The expression of Survivin mRNA is specific in renal cell cancer . It correlates with the clinical stage and pathological grade and could bean effective signal.to monitor the micrometastases of tumor .