Inhibition of human breast cancer cell (MBA-MD-231) invasion by the Ea4-peptide of rainbow trout pro-IGF-I

✍ Scribed by Sineenat Siri; Maria J. Chen; Thomas T. Chen

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 146 KB
• Volume: 99
• Category: Article
• ISSN: 0730-2312
• DOI: 10.1002/jcb.21011

✦ Synopsis

Abstract

It was shown previously that Ea4‐peptide of trout pro‐IGF‐I exerted mitogenic activity in non‐transformed cells and inhibited colony formation in a soft agar medium of established human cancer cells. Here we report that the same peptide inhibits the invasion of human breast cancer cells (MDA‐MB‐231) through a matrigel membrane in a dose‐dependent manner. The expression of urokinase‐type plasminogen activator (uPA), tissue‐type plasminogen activator (tPA) and plasminogen activator inhibitor 1 (PAI1) genes in MDA‐MB‐231 cells were downregulated by treatment with rtEa4‐peptide. The inhibition of expression of these genes in response to rtEa4‐peptide treatment was reduced to the control level when inhibitors for c‐Jun N‐terminal kinase 1/2 (JNK1/2), mitogen activated protein kinase kinase 1/2 (Mek1/2), p38 mitogen activated protein kinase (p38 MAPK), phosphatidylinositol 3‐kinase (PI3K), and phosphokinase C (PKC) were used. These results suggest that inhibition of invasion of MDA‐MB‐231 cells by rtEa4‐peptide may be mediated via the suppression of uPA, tPA, and PAI1 gene activities through signal transduction pathways. J. Cell. Biochem. 99: 1363–1373, 2006. © 2006 Wiley‐Liss, Inc.