BACKGROUND:
Survivin has been implicated in inhibition of
apoptosis. To date, alternatively spliced
isoforms, Survivin-2alpha, -2B, -DeltaEx3, -3B, have been described. We assessed the effect of
survivin gene expression on the proliferation of
renal cancer (RCC) cells, and studied the association of
survivin and its spliced
isoform gene expression levels with the clinical stage of RCC. METHODS:
Gene expression of
survivin and its spliced
isoform in RCC cells, Caki-1, were performed by
RT-PCR. We knocked down the
gene expression of
Survivin using small interfering
RNA (siRNA), and assessed the
cell proliferation by
MTS assay. Next, we quantified the
gene expression levels of
survivin and its
isoform in
nephrectomy samples using quantitative
real-time PCR. RESULTS: In Caki-1 cells,
survivin and survivin-2alpha, -2B were expressed higher than survivin-DeltaEx3. Decrease of
Survivin gene expression by transfection of siRNA was accompanied by inhibition of the proliferation of Caki-1 cell with 36% decrease in comparison with negative control transfected cells (p<0.01). In clinical RCC tissues,
survivin expression levels in
metastatic stage were significantly higher compared with those in distant
metastasis stage (M0:M1=1:4.81, p=0.014);
survivin 2B
gene expression levels in pT3
tumors were associated significantly higher than those in pT1 (pT1:pT3=1:4.50, p=0.043). No significant differences were found in survivin-2alpha expression levels and the ratio of survivin-2B/
survivin gene expression levels among any clinical stages. CONCLUSION: We first demonstrated the
gene expression of survivin-2alpha in
renal cancer cells, and also showed that
survivin and its spliced
isoforms had associations with
renal cancer cell proliferation and distant
metastases.
