[Biological effects of down-regulating of TIZ gene on ovarian cancer cells in vitro].

OBJECTIVE: To construct TIZ gene RNA interference plasmid, as well as study the biological effects of down-regulating of TIZ gene on ovarian cancer cells.

METHODS: According to the mRNA sequence of TIZ on GenBank, 3 pairs of small interference RNA (siRNA) for TIZ gene expression were designed and introduced into SKOV3 cells by liposome transfection reagent; the real-time quantitative PCR (QRT-PCR) was used to detect the interference efficiency and selected the most efficiency siRNA segment; pGPU6/GFP/Neo carrier was used to construct pGPU6/GFP/Neo-siRNA-TIZ-573 restructured interference plasmid, introduced into SKOV3 cell (sh-TIZ-573/SKOV3). The cell growth curves were made by methyl thiazolyl tetrazolium (MTT) method. The clonogenicity efficiency was observed by clony formation test. The cell cycles were measured by flow cytometry (FCM). The ability of invasion, metastasis and adhesion of ovarian cancer cells were detected by the matrigel invasion assay, transwell migration assay and adhesion assay, respectively.

RESULTS: QRT-PCR results showed that ovarian cancer SKOV3 cells which transfected by recombinant plasmids pGPU6/GFP/Neo-siRNA-TIZ-573 could down-express TIZ gene. The cell growth curves, FCM and clony formation tests showed that the growth and proliferation of sh-TIZ-573/SKOV3 cells were significantly speeded up compared with the control cells (P < 0.01). There was no significant difference in cell invasion, migration and adhesion between sh-TIZ-573/SKOV3 cells [(48.5 ± 1.7)%, (53.6 ± 3.4)%, (64.9 ± 5.0)%, respectively] and the control cells (P > 0.05).

CONCLUSION: The growth of ovarian cancer cells could be speeded up by down-expressing of TIZ gene, which TIZ gene may be play a biological role as a tumor suppressor gene.