Galectins: Major Signaling Modulators Inside and Outside the Cell

Abstract

Galectins control cell behavior by acting on different signaling pathways. Most of the biological activities ascribed to these molecules rely upon recognition of extracellular glycoconjugates and establishment of multivalente interactions, which trigger adaptive biological responses. However, galectins are also detected within the cell in different compartments, where their regulatory functions still remain poorly understood. A deeper understanding of the entire galectin signalosome and its impact in cell behavior is therefore essential in order to delineate new strategies to specifically manipulate both galectin expression and function. This review summarizes our current knowledge of the signaling pathways activated by galectins, their glycan dependence and the cellular compartment where they become activated and are biologically relevant.

Towards molecular mechanisms regulating the expression of galectins in cancer cells under microenvironmental stress conditions

“…Third, we do not know what signaling mechanisms regulate the differential expression of galectin genes in cells and whether a collaboration between common and diverse stress-sensitive signaling pathways is required. Considering recent comprehensive reviews and books on galectins [3,5,[12][13][14][15][16][17][35][36][37], the main goal of this short review is to focus specifically on the stress-induced changes in the expression of individual galectins in human cells including cancer cell lines and to point out some potential regulatory mechanisms likely deserving of attention in elucidating the crosstalk between various members of the galectin network at the transcriptional and post-transcriptional levels.…”

Molecular Mechanisms Underlying the Role of Galectin-8 as a Regulator of Cancer Growth and Metastasis

“…Galectin-8 (Gal-8) (1) is a member of the galectin family of animal lectins (2) that regulate a myriad of biological processes including cell growth, cell transformation, embryogenesis, apoptosis, cell adhesion and immune responses [reviewed in (3)(4)(5)(6)(7)]. It is a 34 kDa protein, made of two carbohydrate recognition domains (CRDs) of about 140 amino acid each, joined by a linker peptide of various lengths.…”

Extracellular presence/release of galectins from HTR-8/SVneo extravillous trophoblast cells*

“…Galectins manifest their roles both inside and outside of cells and are also present in the extracellular matrix (Compagno et al, 2014). Most galectins described in humans are present at the fetomaternal interface (Than et al, 2012).…”