Small integrin-binding ligand N-linked glycoproteins (SIBLINGs): multifunctional proteins in cancer

The family of glycophosphoproteins known as small integrin-binding ligand N-linked glycoproteins (SIBLINGs) are emerging as important players in malignant transformation, invasion and metastasis. Could these proteins be promising diagnostic and prognostic tools, as well as therapeutic targets? Numerous components and pathways are involved in the complex interplay between cancer cells and their environment. The family of glycophosphoproteins comprising osteopontin, bone sialoprotein, dentin matrix protein 1, dentin sialophosphoprotein and matrix extracellular phosphoglycoprotein — small integrin-binding ligand N-linked glycoproteins (SIBLINGs) — are emerging as important players in many stages of cancer progression. From their detection in various human cancers to the demonstration of their key functional roles during malignant transformation, invasion and metastasis, the SIBLINGs are proteins with potential as diagnostic and prognostic tools, as well as new therapeutic targets.