title: Size-dependent regulation of Snail2 by hyaluronan: its role in cellular invasion.
abstract: Hyaluronan (HA) induces changes in cellular behavior that are crucial during both embryonic development and cancer progression. However, the biological effects of varying sizes of HA and the signal transduction mechanisms that these polymers may activate remain unclear. In this study, we demonstrate that pulse stimulation of mouse embryonic fibroblasts with high-molecular-weight (HMW) HA, but not HA of lower molecular sizes, leads to increases in Snail2 protein which are dependent on NFkappaB activity. Involvement of CD44, the main HA receptor, in these responses was determined by use of a CD44 blocking antibody and CD44 siRNA. Both the blockade and silencing of CD44 significantly abrogate the increases in nuclear factor kappaB (NFkappaB) activity and Snail2 protein following HMW-HA stimulation. Furthermore, we show that HMW-HA induces cellular invasion and that inhibition of CD44, Snail2, or NFkappaB significantly decreases this response. These studies elucidate a novel HA/Snail2 functional connection through CD44 and NFkappaB that is important for the induction of cellular invasion and is dependent on HA size.
authors.affiliation: Department of Pharmacology and Toxicology, University of Arizona, Tucson, AZ 85721, USA.
authors.forename: Evisabel A
authors.initials: EA
authors.lastname: Craig
authors.forename: Patti
authors.initials: P
authors.lastname: Parker
authors.forename: Todd D
authors.initials: TD
authors.lastname: Camenisch
mesh_terms: D000818:Animals; D002465:Cell Movement / Q000502:physiology*; D005347:Fibroblasts / Q000378:metabolism; D018960:Hyaluronan Receptors / Q000378:metabolism; D006820:Hyaluronic Acid / Q000378:metabolism*; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism; D041681:NIH 3T3 Cells; D015398:Signal Transduction / Q000502:physiology; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D018960:Hyaluronan Receptors; D016328:NF-kappa B; C000604429:Snai1 protein, mouse; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors; D006820:Hyaluronic Acid