Effect of downregulation of osteopontin on biological behaviors and MMP-2 expression of breast cancer cells
- Author:
Nan-Lin JIAO
1
Author Information
1. Department of Pathology and Pathophysiology
- Publication Type:Journal Article
- Keywords:
Breast neoplasms;
Matrix metalloproteinases;
Osteopontin;
Phenotype;
RNA, small interfering
- From:
Tumor
2007;27(12):939-943
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To study the effects of downregulation of osteopontin (OPN) on biological behaviors and matrix metalloproteinase-2 (MMP-2) expression of breast cancer cells MDA-MB-231. Methods: siRNA expression vectors were designed to target OPN and named as pSilence-OPN S 1 and pSilence-OPN S 2. The two plasmids were transfected into MDA-MB-231 cells. The mRNA and protein expression of OPN and MMP-2 were measured by RT-PCR and Western blotting, respectively. The effect of downregulation of OPN on cell proliferation, cell cycle distribution, and malignant phenotype of MDA-MB-231 cells were determined by MIT assay, flow cytometry, and soft agar assay, respectively. The level of MMP-2 protein in the supernatant of cultured cells was measured with ELISA. Results: The expression of OPN in the transfected cells (M-OPN S 1 and M-OPN S 2) was significantly downregulated at both mRNA and protein levels compared with MDA-MB-231 cells. The proliferation of transfected cells was inhibited and the cells were arrested at S phase. Downregulation of OPN caused a significant reduction in colony formation rate and MMP-2 expression. Conclusions: The stable silencing of OPN gene expression with siRNA inhibited the proliferation of MDA-MB-231 cells, downregulats malignant degree and MMP-2 expression. It may provide a novel therapeutic approach for breast cancer therapy.