Invasive behaviour of glioblastoma cell lines is associated with altered organisation of the cadherin-catenin adhesion system.
As little is known about the role of cadherin-mediated cell-cell adhesion in astrocytes and its alteration in migrating and invasive glioblastomas, we investigated its molecular composition and organisation in primary cultured astrocytes and the T98G and U373MG glioblastoma cell lines. Biochemical and morphological analysis indicated that all three cell types express all of the structural components of the adhesion system, including the LIN-7 PDZ protein, a novel component involved in the organisation of the junctional domain in epithelia and neurons. However, only the astrocytes and T98G cells generated and maintained mature adhesive junctional domains to which LIN-7 was recruited. Alterations in the junctional domain of U373MG cells were associated with higher motility in a poly-L-lysine migration assay. When the T98G cells were cultured on Matrigel matrix, they acquired invasive properties but, despite unchanged cadherin adhesion system protein levels, the invasive T98G cell-cell contacts failed to accumulate LIN-7 and failed to mature. These results identify the LIN-7 PDZ protein as a marker of cell adhesion maturity and cell invasion and indicate that instability and disorganisation of cadherin-mediated junctions rather than reduced expression of cadherin-catenin system components are required to promote migration and invasiveness in glioblastoma cell lines.
Department of Pharmacology, Center of Excellence of Neurodegenerative Disease, University of Milan, IN CNR, Italy.
Carla
C
Perego
Cristina
C
Vanoni
Silvia
S
Massari
Andrea
A
Raimondi
Sandra
S
Pola
Maria Grazia
MG
Cattaneo
Maura
M
Francolini
Lucia Maria
LM
Vicentini
Grazia
G
Pietrini
D048868:Adaptor Proteins, Signal Transducing; D022005:Adherens Junctions / Q000378:metabolism; D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism; D001932:Brain Neoplasms / Q000473:pathology / Q000503:physiopathology*; D015820:Cadherins / Q000378:metabolism*; D002448:Cell Adhesion / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D005909:Glioblastoma / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D009361:Neoplasm Invasiveness; D051381:Rats; D017207:Rats, Sprague-Dawley; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000378:metabolism; D033921:Vesicular Transport Proteins; D051176:beta Catenin
D048868:Adaptor Proteins, Signal Transducing; C495270:CTNNB1 protein, human; D015820:Cadherins; C495268:Ctnnb1 protein, rat; D003598:Cytoskeletal Proteins; C119588:LIN-7 protein, mammalian; C486532:LIN7A protein, human; C486531:LIN7C protein, human; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; D015534:Trans-Activators; D033921:Vesicular Transport Proteins; D051176:beta Catenin; D014443:Tyrosine