A novel β1,3- N-acetylglucosaminyltransferase involved in invasion of cancer cells as assayed in vitro

Abstract

Using a two-step screening system for genes involved in tissue invasion [Kataoka et al., Cancer Lett. 163(2) (2001) 213], we identified a cDNA whose expression level was higher in mouse placenta at later stages of gestation and in sublines of cancer cells with low degrees of invasiveness. The deduced amino acid sequence showed relatively high similarity with β1,3- N-acetylglucosaminyltransferase2∼5 (β3GnT2∼5), and the protein was therefore named β3GnT7. A possible human ortholog was identified and its chromosomal locus was determined to be 2q37.1. In the mouse, β3GnT7 was most strongly expressed in the placenta and colon. Moderate amounts of mRNA were detected in the lung, stomach, small intestine, and kidney. The expression of β3GnT7 was very weak in the cerebrum, cerebellum, heart, and testis. Transfection of the antisense oligonucleotide significantly enhanced the motility of a lung cancer cell line (KLN205-MUC1) in a monolayer compared to the controls. Furthermore, the antisense oligonucleotide increased the number of cells that invaded the matrix-coated membrane in an in vitro invasion model. These results indicate that β3GnT7 may play a role in preventing cells from migrating out of the original tissues and invading surrounding tissues.