title: In situ quantification of HER2-protein tyrosine kinase 6 (PTK6) protein-protein complexes in paraffin sections from breast cancer tissues.
abstract: BACKGROUND
  Protein tyrosine kinase 6 (PTK6; breast tumour kinase) is overexpressed in up to 86% of the invasive breast cancers, and its association with the oncoprotein human epidermal growth factor receptor 2 (HER2) was shown in vitro by co-precipitation. Furthermore, expression of PTK6 in tumours is linked with the expression of HER2.
  
  
  RESULTS
  In this study, we used the proximity ligation assay (PLA) technique on formalin-fixed paraffin sections from eighty invasive breast carcinoma tissue specimens to locate PTK6-HER2 protein-protein complexes. Proximity ligation assay signals from protein complexes were assessed quantitatively, and expression levels showed a statistically significant association with tumour size (P=0.015) and course of the cancer disease (P=0.012).
  
  
  CONCLUSIONS
  Protein tyrosine kinase 6 forms protein complexes with HER2 in primary breast cancer tissues, which can be visualised by use of the PLA technique. Human epidermal growth factor receptor 2-PTK6 complexes are of prognostic relevance.
authors.affiliation: Institute of Pathology, Helmholtz Zentrum München, German Research Center for Environmental Health, D-85764 Neuherberg, Germany. aubele@helmholtz-muenchen.de
authors.forename: M
authors.initials: M
authors.lastname: Aubele
authors.forename: M
authors.initials: M
authors.lastname: Spears
authors.forename: N
authors.initials: N
authors.lastname: Ludyga
authors.forename: H
authors.initials: H
authors.lastname: Braselmann
authors.forename: A
authors.initials: A
authors.lastname: Feuchtinger
authors.forename: K J
authors.initials: KJ
authors.lastname: Taylor
authors.forename: K
authors.initials: K
authors.lastname: Lindner
authors.forename: G
authors.initials: G
authors.lastname: Auer
authors.forename: K
authors.initials: K
authors.lastname: Stering
authors.forename: H
authors.initials: H
authors.lastname: Höfler
authors.forename: M
authors.initials: M
authors.lastname: Schmitt
authors.forename: J M S
authors.initials: JM
authors.lastname: Bartlett
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D009363:Neoplasm Proteins / Q000378:metabolism*; D016612:Paraffin Embedding; D011485:Protein Binding; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*
chemical_list: D009363:Neoplasm Proteins; D011505:Protein-Tyrosine Kinases; D018719:Erb-b2 Receptor Tyrosine Kinases; C088375:PTK6 protein, human