J Cancer 2011; 2:165-176. doi:10.7150/jca.2.165

Research Paper

Protein Signatures in Human MDA-MB-231 Breast Cancer Cells Indicating a More Invasive Phenotype Following Knockdown of Human Endometase/Matrilysin-2 by siRNA

Seakwoo Lee1*, Doris Terry2, Douglas R. Hurst3, Danny R. Welch3, Qing-Xiang Amy Sang1✉

1. Department of Chemistry and Biochemistry and Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306-4390, USA;
2. Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, Florida 32306-4390, USA;
3. Department of Pathology, Comprehensive Cancer Center, and National Foundation for Cancer Research Center for Metastasis Research, University of Alabama at Birmingham, Birmingham, Alabama, USA.
* Present address: Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, 21205, USA.

Abstract

Human matrix metalloproteinase-26 (MMP-26/endometase/matrilysin-2) is a putative biomarker for carcinomas of breast, prostate, and other cancers of epithelial origin. MMP-26 expression was silenced using small interfering RNA (siRNA) in the human breast cancer cell line MDA-MB-231. Immunological and proteomics approaches, including two-dimensional gel electrophoresis and matrix assisted laser desorption/ionization time-of-flight mass spectrometry, were employed to identify differential protein expression in MMP-26 knockdown cells. A comparison of the protein expression profiles of control and MMP-26 knockdown cells revealed nine differentially regulated proteins. Five of the proteins (heat shock protein 90, glucose-regulated protein 78 (GRP78), annexin V, tropomyosin, and peroxiredoxin II) were up-regulated, while alpha-tubulin, cystatin SA-III, breast cancer metastasis suppressor 1 (BRMS1) and beta-actin were down-regulated. This decrease of BRMS1 expression is concomitant with an increase of invasion through matrix-coated membranes. These results suggest an important role for MMP-26 in the regulation of proteins involved in invasive and metastatic breast cancers.

Keywords: Matrix metalloproteinase (MMP), MMP-26, breast cancer metastasis suppressor 1, putative protein biomarkers, invasion and metastasis, mass spectrometry, proteomics

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How to cite this article:
Lee S, Terry D, Hurst DR, Welch DR, Sang QXA. Protein Signatures in Human MDA-MB-231 Breast Cancer Cells Indicating a More Invasive Phenotype Following Knockdown of Human Endometase/Matrilysin-2 by siRNA. J Cancer 2011; 2:165-176. doi:10.7150/jca.2.165. Available from http://www.jcancer.org/v02p0165.htm