Tumor suppressor p16INK4a--modulator of glycomic profile and galectin-1 expression to increase susceptibility to carbohydrate-dependent induction of anoikis in pancreatic carcinoma cells

Item Type:	Review
Title:	Tumor suppressor p16INK4a--modulator of glycomic profile and galectin-1 expression to increase susceptibility to carbohydrate-dependent induction of anoikis in pancreatic carcinoma cells
Creators Name:	Andre, S. and Sanchez-Ruderisch, H. and Nakagawa, H. and Buchholz, M. and Kopitz, J. and Forberich, P. and Kemmner, W. and Boeck, C. and Deguchi, K. and Detjen, K.M. and Wiedenmann, B. and von Knebel Doeberitz, M. and Gress, T.M. and Nishimura, S. and Rosewicz, S. and Gabius, H.J.
Abstract:	Expression of the tumor suppressor p16(INK4a) after stable transfection can restore the susceptibility of epithelial tumor cells to anoikis. This property is linked to increases in the expression and cell-surface presence of the fibronectin receptor. Considering its glycan chains as pivotal signals, we assumed an effect of p16(INK4a) on glycosylation. To test this hypothesis for human Capan-1 pancreatic carcinoma cells, we combined microarray for selected glycosyltransferase genes with 2D chromatographic glycan profiling and plant lectin binding. Major differences between p16-positive and control cells were detected. They concerned expression of beta1,4-galactosyltransferases (down-regulation of beta1,4-galactosyltransferases-I/V and up-regulation of beta1,4-galactosyltransferase-IV) as well as decreased alpha2,3-sialylation of O-glycans and alpha2,6-sialylation of N-glycans. The changes are compatible with increased beta(1)-integrin maturation, subunit assembly and binding activity of the alpha(5)beta(1)-integrin. Of further functional relevance in line with our hypothesis, we revealed differential reactivity towards endogenous lectins, especially galectin-1. As a result of reduced sialylation, the cells' capacity to bind galectin-1 was enhanced. In parallel, the level of transcription of the galectin-1 gene increased conspicuously in p16(INK4a)-positive cells, and even figured prominently in a microarray on 1996 tumor-associated genes and in proteomic analysis. The cells therefore gain optimal responsiveness. The correlation between genetically modulated galectin-1 levels and anoikis rates in engineered transfectants inferred functional significance. To connect these findings to the fibronectin receptor, galectin-1 was shown to be co-immunoprecipitated. We conclude that p16(INK4a) orchestrates distinct aspects of glycosylation that are relevant for integrin maturation and reactivity to an endogenous effector as well as the effector's expression. This mechanism establishes a new aspect of p16(INK4a) functionality.
Keywords:	Anoikis, Fibronectin Receptor, Galectin, Glycosyltransferases, Pancreas Tumor
Source:	FEBS Journal
ISSN:	1742-464X
Publisher:	Blackwell Publishing
Volume:	274
Number:	13
Page Range:	3233-3256
Date:	July 2007
Official Publication:	https://doi.org/10.1111/j.1742-4658.2007.05851.x
PubMed:	View item in PubMed

Repository Staff Only: item control page