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Silencing of IQGAP1 by shRNA inhibits the invasion of ovarian carcinoma HO-8910PM cells in vitro.

Dong PX, Jia N, Xu ZJ, Liu YT, Li DJ, Feng YJ - J. Exp. Clin. Cancer Res. (2008)

Bottom Line: Levels of both IQGAP1 mRNA and protein were significantly reduced in HO-8910PM cells transfected with plasmid-based IQGAP1-specific shRNAs.RNAi-mediated knockdown of IQGAP1 expression in HO-8910PM cells resulted in a significant decrease in cell invasion and migration.Our findings support the hypothesis that IQGAP1 promotes tumor progression and identify IQGAP1 as a potential therapeutic strategy for ovarian cancer and some other tumors with over-expression of the IQGAP1 gene.

View Article: PubMed Central - HTML - PubMed

Affiliation: Hospital and Institute of Obstetrics and Gynecology, Fudan University Shanghai Medical, College, Shanghai, PR China. dpx1cn@yahoo.com.cn

ABSTRACT

Background: IQGAP1 is a scaffolding protein and overexpressed in many human tumors, including ovarian cancer. However, the contribution of IQGAP1 to invasive properties of ovarian cancer cells remains unknown. Here, we investigated the effect of IQGAP1-specific short hairpin RNA (shRNA) expressing plasmids on metastatic potential of ovarian cancer HO-8910PM cells.

Methods: We used RT-PCR and Western blot analysis to characterize expression of IQGAP1 in three human ovarian cancer-derived cell lines SK-OV-3, HO-8910 and HO-8910PM. We then determined whether expression of endogenous IQGAP1 correlated with invasive and migratory ability by using an in vitro Matrigel assay and cell migration assay. We further knocked down IQGAP1 using shRNA expressing plasmids controlled by U1 promoter in HO-8910PM cells and examined the proliferation activity, invasive and migration potential of IQGAP1 shRNA transfectants using MTT assay, in vitro Matrigel-coated invasion assay and migration assay.

Results: IQGAP1 expression level seemed to be closely associated with the enhanced invasion and migration in ovarian cancer cell lines. Levels of both IQGAP1 mRNA and protein were significantly reduced in HO-8910PM cells transfected with plasmid-based IQGAP1-specific shRNAs. RNAi-mediated knockdown of IQGAP1 expression in HO-8910PM cells resulted in a significant decrease in cell invasion and migration.

Conclusion: Our findings support the hypothesis that IQGAP1 promotes tumor progression and identify IQGAP1 as a potential therapeutic strategy for ovarian cancer and some other tumors with over-expression of the IQGAP1 gene.

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indicates that silencing of IQGAP1 inhibited ovarian cancer cell invasion and migration in vitro. (a) Suppression of IQGAP1 hampered transmembrane migration ability of HO-8910PM cells. HO-8910PM-shIQGAP1, HO-8910PM-shRNA negative and un-transfected HO-8910PM cells were seeded onto a Matrigel-coated invasion chamber and the number of invading cells was determined as described before.  *, P < 0.05 versus HO-8910PM-shRNA negative or un-transfected HO-8910PM cells.     (b) Suppression of IQGAP1 decreased migration of HO-8910PM cells. HO-8910PM-shIQGAP1, HO-8910PM-shRNA negative and un-transfected HO-8910PM cells were seeded onto a Boyden chamber and the number of migrating cells was determined as described before.  *, P < 0.05 versus HO-8910PM-shRNA negative or un-transfected HO-8910PM cells.
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Figure 4: indicates that silencing of IQGAP1 inhibited ovarian cancer cell invasion and migration in vitro. (a) Suppression of IQGAP1 hampered transmembrane migration ability of HO-8910PM cells. HO-8910PM-shIQGAP1, HO-8910PM-shRNA negative and un-transfected HO-8910PM cells were seeded onto a Matrigel-coated invasion chamber and the number of invading cells was determined as described before. *, P < 0.05 versus HO-8910PM-shRNA negative or un-transfected HO-8910PM cells. (b) Suppression of IQGAP1 decreased migration of HO-8910PM cells. HO-8910PM-shIQGAP1, HO-8910PM-shRNA negative and un-transfected HO-8910PM cells were seeded onto a Boyden chamber and the number of migrating cells was determined as described before. *, P < 0.05 versus HO-8910PM-shRNA negative or un-transfected HO-8910PM cells.

Mentions: Invasion of basement membranes by tumor cell is thought to be a critical event in the cascade of metastasis. It has been shown that over-expression of IQGAP1 enhances the capacity of human breast adenocarcinoma MCF-7 cell for transmembrane migration by up-regulating the expression active CDC42 and Rac1 [17]. To evaluate whether silencing of IQGAP1 contributes to the reduced invasive behavior of ovarian cancer cells, we examined the invasive potential of IQGAP1 shRNA transfectants using an in vitro Matrigel-coated invasion assay. HO-8910PM-shIQGAP1 cells displayed a significantly lower transmembrane migration activity as compared to HO-8910PM-shRNA negative and un-transfected HO-8910PM cells (Fig 4a). This result suggested that suppression of IQGAP1 by shRNA resulted in a significant decrease in the invasiveness of ovarian cancer cells.


Silencing of IQGAP1 by shRNA inhibits the invasion of ovarian carcinoma HO-8910PM cells in vitro.

Dong PX, Jia N, Xu ZJ, Liu YT, Li DJ, Feng YJ - J. Exp. Clin. Cancer Res. (2008)

indicates that silencing of IQGAP1 inhibited ovarian cancer cell invasion and migration in vitro. (a) Suppression of IQGAP1 hampered transmembrane migration ability of HO-8910PM cells. HO-8910PM-shIQGAP1, HO-8910PM-shRNA negative and un-transfected HO-8910PM cells were seeded onto a Matrigel-coated invasion chamber and the number of invading cells was determined as described before.  *, P < 0.05 versus HO-8910PM-shRNA negative or un-transfected HO-8910PM cells.     (b) Suppression of IQGAP1 decreased migration of HO-8910PM cells. HO-8910PM-shIQGAP1, HO-8910PM-shRNA negative and un-transfected HO-8910PM cells were seeded onto a Boyden chamber and the number of migrating cells was determined as described before.  *, P < 0.05 versus HO-8910PM-shRNA negative or un-transfected HO-8910PM cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Figure 4: indicates that silencing of IQGAP1 inhibited ovarian cancer cell invasion and migration in vitro. (a) Suppression of IQGAP1 hampered transmembrane migration ability of HO-8910PM cells. HO-8910PM-shIQGAP1, HO-8910PM-shRNA negative and un-transfected HO-8910PM cells were seeded onto a Matrigel-coated invasion chamber and the number of invading cells was determined as described before. *, P < 0.05 versus HO-8910PM-shRNA negative or un-transfected HO-8910PM cells. (b) Suppression of IQGAP1 decreased migration of HO-8910PM cells. HO-8910PM-shIQGAP1, HO-8910PM-shRNA negative and un-transfected HO-8910PM cells were seeded onto a Boyden chamber and the number of migrating cells was determined as described before. *, P < 0.05 versus HO-8910PM-shRNA negative or un-transfected HO-8910PM cells.
Mentions: Invasion of basement membranes by tumor cell is thought to be a critical event in the cascade of metastasis. It has been shown that over-expression of IQGAP1 enhances the capacity of human breast adenocarcinoma MCF-7 cell for transmembrane migration by up-regulating the expression active CDC42 and Rac1 [17]. To evaluate whether silencing of IQGAP1 contributes to the reduced invasive behavior of ovarian cancer cells, we examined the invasive potential of IQGAP1 shRNA transfectants using an in vitro Matrigel-coated invasion assay. HO-8910PM-shIQGAP1 cells displayed a significantly lower transmembrane migration activity as compared to HO-8910PM-shRNA negative and un-transfected HO-8910PM cells (Fig 4a). This result suggested that suppression of IQGAP1 by shRNA resulted in a significant decrease in the invasiveness of ovarian cancer cells.

Bottom Line: Levels of both IQGAP1 mRNA and protein were significantly reduced in HO-8910PM cells transfected with plasmid-based IQGAP1-specific shRNAs.RNAi-mediated knockdown of IQGAP1 expression in HO-8910PM cells resulted in a significant decrease in cell invasion and migration.Our findings support the hypothesis that IQGAP1 promotes tumor progression and identify IQGAP1 as a potential therapeutic strategy for ovarian cancer and some other tumors with over-expression of the IQGAP1 gene.

View Article: PubMed Central - HTML - PubMed

Affiliation: Hospital and Institute of Obstetrics and Gynecology, Fudan University Shanghai Medical, College, Shanghai, PR China. dpx1cn@yahoo.com.cn

ABSTRACT

Background: IQGAP1 is a scaffolding protein and overexpressed in many human tumors, including ovarian cancer. However, the contribution of IQGAP1 to invasive properties of ovarian cancer cells remains unknown. Here, we investigated the effect of IQGAP1-specific short hairpin RNA (shRNA) expressing plasmids on metastatic potential of ovarian cancer HO-8910PM cells.

Methods: We used RT-PCR and Western blot analysis to characterize expression of IQGAP1 in three human ovarian cancer-derived cell lines SK-OV-3, HO-8910 and HO-8910PM. We then determined whether expression of endogenous IQGAP1 correlated with invasive and migratory ability by using an in vitro Matrigel assay and cell migration assay. We further knocked down IQGAP1 using shRNA expressing plasmids controlled by U1 promoter in HO-8910PM cells and examined the proliferation activity, invasive and migration potential of IQGAP1 shRNA transfectants using MTT assay, in vitro Matrigel-coated invasion assay and migration assay.

Results: IQGAP1 expression level seemed to be closely associated with the enhanced invasion and migration in ovarian cancer cell lines. Levels of both IQGAP1 mRNA and protein were significantly reduced in HO-8910PM cells transfected with plasmid-based IQGAP1-specific shRNAs. RNAi-mediated knockdown of IQGAP1 expression in HO-8910PM cells resulted in a significant decrease in cell invasion and migration.

Conclusion: Our findings support the hypothesis that IQGAP1 promotes tumor progression and identify IQGAP1 as a potential therapeutic strategy for ovarian cancer and some other tumors with over-expression of the IQGAP1 gene.

Show MeSH
Related in: MedlinePlus