title: αB-crystallin expression is correlated with phospho-ERK1/2 expression in human breast cancer.
abstract: αB-crystallin is regarded as a biomarker for triple-negative and/or basal-like breast cancer. In normal breast cells, overexpression of αB-crystallin leads to neoplastic-like changes, which likely relate to enhanced expression of phosphorylated ERK1/2 (pERK1/2). In this study, we investigated whether αB-crystallin expression is correlated to pERK1/2 expression in breast cancer. In a balanced tissue microarray the expression of αB-crystallin and pERK1/2 kinase were determined immunohistochemically, together with the triple-negativity and basal-like markers CK5/6 and SMA and the signaling molecules pAKT, pmTOR, EGFR, and IGF-1R. αB-crystallin expression significantly correlated with triple negativity and basal-like markers CK5/6 and SMA (Pearson Chi-square test p=0.004, p=0.001, and p&lt;0.001, respectively). A significant correlation was also observed with pERK1/2 expression (p=0.002). siRNA-mediated knockdown of αB-crystallin in the triple-negative breast cell line MDA-MB468 did not show an effect on pERK1/2 expression levels, indicating that lowering the level of αB-crystallin does not reduce pERK1/2 expression. Our results confirm that αB-crystallin can be used as a biomarker for triple-negative and/or basal-like breast cancer. The expression of αB-crystallin correlates with pERK1/2 expression in breast cancer tissue suggesting that therapies targeting αB-crystallin might be considered for treatment of triple-negative or basal-like breast cancer.
authors.affiliation: Department of Biomolecular Chemistry, Institute for Molecules and Materials and Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen - The Netherlands.
authors.forename: Chantal
authors.initials: C
authors.lastname: van de Schootbrugge
authors.forename: Freekje
authors.initials: F
authors.lastname: van Asten
authors.forename: Iris D
authors.initials: ID
authors.lastname: Nagtegaal
authors.forename: Yvonne M
authors.initials: YM
authors.lastname: Versleijen-Jonkers
authors.forename: Hanneke W M
authors.initials: HW
authors.lastname: van Laarhoven
authors.forename: Melissa H
authors.initials: MH
authors.lastname: Roeffen
authors.forename: Fred C G J
authors.initials: FC
authors.lastname: Sweep
authors.forename: Johan
authors.initials: J
authors.lastname: Bussink
authors.forename: Johannes H A M
authors.initials: JH
authors.lastname: Kaanders
authors.forename: Ger J M
authors.initials: GJ
authors.lastname: Pruijn
authors.forename: Wilbert C
authors.initials: WC
authors.lastname: Boelens
authors.forename: Paul N
authors.initials: PN
authors.lastname: Span
mesh_terms: D014408:Biomarkers, Tumor / Q000096:biosynthesis; D045744:Cell Line, Tumor; D015331:Cohort Studies; D005260:Female; D055785:Gene Knockdown Techniques; D006801:Humans; D007150:Immunohistochemistry; D019950:Mitogen-Activated Protein Kinase 1 / Q000096:biosynthesis* / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000096:biosynthesis* / Q000378:metabolism; D010766:Phosphorylation; D064726:Triple Negative Breast Neoplasms / Q000201:enzymology / Q000378:metabolism*; D038203:alpha-Crystallin B Chain / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; D038203:alpha-Crystallin B Chain; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3