Objective: To study the inhibition effect of survivin antisense RNA on the growth of ovarian carcinoma SKOV3 cells, and the tumorigenic ability of the transfected SKOV3 cells implanted subcutaneously in nude mice.
Methods: The recombinant vector pcDNA3-SVVas was constructed by directed cloning of fragments of survivin cDNA into the vector. The ovarian carcinoma SKOV3 cells were transfected with pcDNA3-SVVas by lipofectamine 2000 (SKOV3/SVVas cells), and blank vector pcDNA3 as control (SKOV3/neo cells). The effect of survivin antisense RNA on cell growth was assessed by growth curve. The inhibition of expression of endogenous survivin protein and mRNA was evaluated by immunohistochemical stain and RT-PCR. The apoptosis of cells was assessed by flow cytometry. Twenty-four nude mice were divided into three groups, then SKOV3/SVVas, SKOV3/neo and SKOV3 cells were implanted subcutaneously. The growth of tumor was observed and the tumor volume calculated.
Results: The expression of survivin significantly decreased in SKOV3/SVVas cells in comparison to that in SKOV3 and SKOV3/neo cells. The growth of the SKOV3/SVVas cells became significantly slower than those of SKOV3 cells and SKOV3/neo cells (P < 0.01). The expression of survivin protein and mRNA in the SKOV3/SVVas cells were (37.5 +/- 1.0)% and 0.407 +/- 0.022 respectively, compared with SKOV3 [(81.2 +/- 0.4)%, 0.793 +/- 0.042] and SKOV3/neo [(80.4 +/- 0.8)%, 0.734 +/- 0.039]. The difference was significant (P < 0.01). After transfected with pcDNA3-SVVas, cells were found apoptosis in early stage by flow cytometry. The apoptosis rate was (27.4 +/- 9.6)%. There was significant difference between SKOV3/SVVas cells and SKOV3 cells, as well as between SKOV3/SVVas and SKOV3/neo cells (P < 0.05). The tumorigenic ability of SKOV3/SVVas cells was reduced. The first time that tumor could be detected in SKOV3/SVVas group, (14.0 +/- 1.0) days was significantly prolonged compared to SKOV3/neo, (6.1 +/- 0.8) days and SKOV3, (5.8 +/- 0.9) days (P < 0.01). In SKOV3/SVVas group, 5 of 8 nude mice were found tumor, the growth rate of tumor was slower compared with the other two groups. When compared in volume, the difference was significant (P < 0.01).
Conclusions: Stable expression of survivin antisense RNA can effectively inhibit the growth of SKOV3 cells and reduce the expression of endogenous survivin proteins and mRNA, induce the apoptosis of cells. Survivin antisense RNA can inhibit the tumorigenesis of SKOV3 cells in nude mice.