Galectin-3 and Regulation of Cell Function

Abstract

The galectin family is phylogenically conserved in metazoans, presently consisting of 14 identified members in mammals, and galectin-3 is one of the most abundant, widely distributed, and well-studied members. It is present intracellularly in nuclear and cytoplasmic compartments, but is also secreted through an unconventional mechanism that involves vesicles and exosomes and, consequently, present outside the cell. While galectin-3 shares many features with other galectins, including cellular compartmentalization and functions, it appears to be unique in its structural constituency in the N-terminal domain, which is rich in proline, glycine, and alanine. It is through this domain that galectin-3 is able to form oligomers, and this may be one feature that functionally differentiates it from other galectins. Galectin-3 has been associated with several intracellular and extracellular functions, and recent investigations have uncovered proteins through which this lectin mediates its activities. The availability of targeted mutant mice deficient in galectin- 3 and other proteins has also contributed to our appreciation of the breadth of processes in which this protein is involved. Among cell functions attributable to galectin-3 are some that are associated with neoplastic transformation and invasiveness, but the most extensively documented ones are those related to the immune and inflammatory responses.

Lactose‐Functionalized Dendrimers Arbitrate the Interaction of Galectin‐3/MUC1 Mediated Cancer Cellular Aggregation

“…Found inside and on the surface of most healthy cells, galectin‐3 is involved in regulating cell growth, differentiation, adhesion, and death 1. Galectin‐3 is a chimeric lectin, with a carbohydrate recognition domain (CRD) specific for β‐galactosides and a collagen‐like tail capable of forming pentamers and other oligomers at high concentrations or when interacting with multivalent frameworks 2–8. Galectin‐3 is overexpressed in many forms of cancer,9, 10 and there is a correlation between the amount of circulating galectin‐3 and the aggressiveness of the cancer 11.…”