title: ShRNA-mediated gene silencing of MTA1 influenced on protein expression of ER alpha, MMP-9, CyclinD1 and invasiveness, proliferation in breast cancer cell lines MDA-MB-231 and MCF-7 in vitro.
abstract: BACKGROUND
  MTA1(metastasis associated-1) is a tumor metastasis associated candidate gene and overexpression in many human tumors, including breast cancer. In this study, we investigated depressive effect on MTA1 by MTA1-specific short hairpin RNA(shRNA) expression plasmids in human breast cancer cell lines MDA-MB-231 and MCF-7, and effect on protein levels of ER alpha, MMP-9, cyclinD1, and tumor cell invasion, proliferation.
  
  
  METHODS
  ShRNA expression vectors targeting MTA1 was constructed and transfected into human breast cancer cell lines MDA-MB-231 and MCF-7. The transfection efficiency was evaluated by fluorescence microscopy, mRNA levels of MTA1 were detected by reverse transcription-polymerase chain reaction (RT-PCR), protein levels of ER alpha, MMP-9 and cyclinD1 were detected by Western blotting, respectively. Tumor cells invasive ability were evaluated by Boyden chamber assay, the cells proliferation were evaluated using cell growth curve and MTT analysis, the cell cycle analysis was performed using flow cytometry.
  
  
  RESULTS
  Down-regulation of MTA1 by RNAi approach led to re-expression of ER alpha in ER-negative breast cancer cell lines MDA-MB-231, and reduced protein levels of MMP-9 and CyclinD1, as well as decreased tumor cell invasion and proliferation, more cells were blocked in G0/G1 stage(P < 0.05). However, after inhibiting mRNA levels of MTA1, protein expression of ER alpha, MMP-9, cyclinD1 and the changes of cancer cells invasiveness, proliferation, cells cycle were no statistical difference in ER-positive human breast cancer cell lines MCF-7 (P > 0.05).
  
  
  CONCLUSIONS
  ShRNA targeted against MTA1 could specifically mediate the MTA1 gene silencing and consequentially recover the protein expression of ER alpha, resulting in increase sensitivity of antiestrogens, as well as suppress the protein levels of MMP-9 and cyclinD1 in ER-negative human breast cancer cell lines MDA-MB-231. Silencing effect of MTA1 could efficiently inhibit the invasion and proliferation in MDA-MB-231 cells. The shRNA interference targeted against MTA1 may have potential therapeutic utility in human breast cancer.
authors: Department of Pathology, School of Basic Medicine Sciences, Chong Qing University of Medical Sciences, Chong Qing, 400016, China.
authors: Qingming
authors: Q
authors: Jiang
authors: Hui
authors: H
authors: Zhang
authors: Ping
authors: P
authors: Zhang
references: J Biol Chem. 1994 Sep 16;269(37):22958-63
references: 8083195
references: J Cell Biochem. 2000 Aug 2;79(2):202-12
references: 10967548
references: Development. 2004 Jul;131(14):3469-79
references: 15226262
references: Genome Biol. 2004;5(9):R66
references: 15345050
references: Nature. 1986 Mar 13-19;320(6058):134-9
references: 3754034
references: CA Cancer J Clin. 2011 Mar-Apr;61(2):69-90
references: 21296855
references: Arch Histol Cytol. 2004 Dec;67(5):435-42
references: 15781984
references: J Thorac Oncol. 2010 Aug;5(8):1159-66
references: 20661085
references: Proc Natl Acad Sci U S A. 1992 Dec 1;89(23):11538-42
references: 1454845
references: J Biol Chem. 2000 Aug 4;275(31):23462-70
references: 10811646
references: Gene. 1995 Jun 14;159(1):97-104
references: 7607577
references: Histol Histopathol. 1999 Apr;14(2):665-71
references: 10212827
references: Cancer Sci. 2006 May;97(5):374-9
references: 16630134
references: Chem Biol Interact. 2007 Feb 20;165(3):220-9
references: 17240363
references: Rev Invest Clin. 2010 Jan-Feb;62(1):81-90
references: 20415062
references: FASEB J. 2006 Jul;20(9):1293-9
references: 16816104
references: J Biol Chem. 2003 Oct 24;278(43):42560-8
references: 12920132
references: World J Surg. 2009 Sep;33(9):1876-81
references: 19575142
references: Cancer Res. 1987 Jun 15;47(12):3239-45
references: 2438036
references: J Biol Chem. 2003 Mar 28;278(13):11676-85
references: 12527756
references: Neoplasia. 1999 Oct;1(4):368-72
references: 10935492
references: Mol Endocrinol. 2005 Jul;19(7):1740-51
references: 15746193
references: Nat Cell Biol. 2001 Jan;3(1):30-7
references: 11146623