title: Implication of α2β1 integrin in anoikis of MCF-7 human breast carcinoma cells.
abstract: Silencing of α2β1 integrin expression significantly promoted anchorage-dependent apoptosis (anoikis) and drastically reduced clonal activity of MCF-7 human breast carcinoma cells. Depletion of α2β1 enhanced the production of apoptotic protein p53 and of inhibitor of cyclin-dependent protein kinases, p27, while downregulating antiapoptotic protein Bcl-2 and multifunctional protein cMyc. Blocking the expression of α2β1 had no effect on activity of protein kinase Akt, but it sharply increased the kinase activity of Erk1/2. Pharmacological inhibition of Erk1/2 had a minor effect on anoikis of control cells, while it reduced anoikis of cells with downregulated α2β1 to the level of control cells. The data show for the first time that integrin α2β1 is implicated in the protection of tumor cells from anoikis through a mechanism based on the inhibition of protein kinase Erk.
authors.affiliation: Orekhovich Institute of Biomedical Chemistry, Russian Academy of Medical Sciences, Moscow, 119121, Russia. 1938berman@gmail.com.
authors.forename: G E
authors.initials: GE
authors.lastname: Morozevich
authors.forename: N I
authors.initials: NI
authors.lastname: Kozlova
authors.forename: O Y
authors.initials: OY
authors.lastname: Susova
authors.forename: P A
authors.initials: PA
authors.lastname: Karalkin
authors.forename: A E
authors.initials: AE
authors.lastname: Berman
mesh_terms: D023102:Anoikis; D001943:Breast Neoplasms / Q000201:enzymology / Q000378:metabolism*; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D006801:Humans; D038982:Integrin alpha2beta1 / Q000502:physiology*; D020935:MAP Kinase Signaling System; D061986:MCF-7 Cells; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: D038982:Integrin alpha2beta1; D016159:Tumor Suppressor Protein p53; D050760:Cyclin-Dependent Kinase Inhibitor p27; D048049:Extracellular Signal-Regulated MAP Kinases