The newcomer in the integrin family: integrin α9 in biology and cancer.
Integrins are heterodimeric transmembrane receptors regulating cell-cell and cell-extracellular matrix interactions. Of the 24 integrin heterodimers identified in humans, α9β1 integrin is one of the least studied. α9, together with α4, comprise a more recent evolutionary sub-family of integrins that is only found in vertebrates. Since α9 was thought to have similar functions as α4, due to many shared ligands, it was a rather overlooked integrin until recently, when its importance for survival after birth was highlighted upon investigation of the α9 knockout mouse. α9β1 is expressed on a wide variety of cell types, interacts with many ligands for example fibronectin, tenascin-C and ADAM12, and has been shown to have important functions in processes such as cell adhesion and migration, lung development, lymphatic and venous valve development, and in wound healing. This has sparked an interest to investigate α9β1-mediated signaling and its regulation. This review gives an overview of the recent progress in α9β1-mediated biological and pathological processes, and discusses its potential as a target for cancer diagnosis and therapy.
Department of Biomedical Sciences, The Faculty of Health and Medical Sciences, and Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen Biocenter, Ole Maaløes Vej 5, Copenhagen N 2200, Denmark.
Anette M
AM
Høye
John R
JR
Couchman
Ulla M
UM
Wewer
Kiyoko
K
Fukami
Atsuko
A
Yoneda
D051722:ADAM Proteins / Q000378:metabolism; D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D006801:Humans; D039001:Integrin alpha Chains / Q000235:genetics / Q000502:physiology*; D039441:Integrin alpha4 / Q000502:physiology; D016023:Integrins / Q000502:physiology; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D009369:Neoplasms / Q000503:physiopathology; D015398:Signal Transduction / Q000502:physiology; D019063:Tenascin / Q000378:metabolism; D042442:Vascular Endothelial Growth Factors / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology
D039001:Integrin alpha Chains; D016023:Integrins; D008562:Membrane Glycoproteins; D019063:Tenascin; D042442:Vascular Endothelial Growth Factors; C030340:elastin microfibril interface located protein; C113256:integrin alpha 9 beta 1; C084613:integrin alpha9; D039441:Integrin alpha4; D051722:ADAM Proteins