The effect of receptor protein tyrosine phosphatase kappa on the change of cell adhesion and proliferation induced by N-acetylglucosaminyltransferase V.

Abstract

N-acetylglucosaminyltransferase V (GnT-V) has been reported to be positively associated with tumor progression, but its mechanism still remains unknown. In the present study, we found that GnT-V overexpression not only changed the glycosylation of receptor protein tyrosine phosphatase kappa (RPTPkappa) but also decreased its protein level. Moreover, GnT-V overexpression decreased cell calcium-independent adhesion and increased the tyrosine phosphorylation level of beta-catenin, in which RPTPkappa played an important role. Since RPTPkappa has an RXKR motif, which is a favored cleavage site for furin, we used furin inhibitor to further explore the effect of RPTPkappa on the change of cell adhesion and beta-catenin signaling induced by GnT-V. Our results showed that preventing RPTPkappa cleavage rescued the above effects of GnT-V, suggesting that furin cleavage could be one of the factors for RPTPkappa to regulate cell adhesion and beta-catenin signaling in GnT-V overexpression cell lines. In addition, the increased tyrosine phosphorylation level of beta-catenin was associated with the increased nuclear level of beta-catenin and downstream signaling molecules such as c-myc and cyclin D1 that were associated with cell proliferation. Our results suggest that GnT-V could decrease human hepatoma SMMC-7721 cell adhesion and promote cell proliferation partially through RPTPkappa.

• Authors: Can Wang, Zengxia Li, Zhaohua Yang, Hongbo Zhao, Yong Yang, Kangli Chen, Xiumei Cai, Liying Wang, Yinghong Shi, Shuangjian Qiu, Jia Fan, Xiliang Zha
• Journal: Journal of cellular biochemistry (J Cell Biochem) Vol. 109 Issue 1 Pg. 113-23 (Jan 01 2010) ISSN: 1097-4644 [Electronic] United States
• PMID: 19911372 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• beta Catenin
• N-Acetylglucosaminyltransferases
• alpha-1,6-mannosylglycoprotein beta 1,6-N-acetylglucosaminyltransferase
• PTPRK protein, human
• Receptor-Like Protein Tyrosine Phosphatases, Class 2

Topics

• Blotting, Western
• Cell Adhesion (physiology)
• Cell Line, Tumor
• Cell Proliferation
• Fluorescent Antibody Technique
• Humans
• Immunoprecipitation
• N-Acetylglucosaminyltransferases (metabolism)
• RNA Interference
• Receptor-Like Protein Tyrosine Phosphatases, Class 2 (metabolism)
• Reverse Transcriptase Polymerase Chain Reaction
• Signal Transduction (physiology)
• beta Catenin (metabolism)