Protein phosphatase-2A association with microtubules and its role in restricting the invasiveness of human head and neck squamous cell carcinoma cells.
The role of protein phosphatase-2A (PP-2A) in regulating the motility and adhesion of human head and neck squamous cell carcinomas (HNSCC) was investigated. Immunofluorescent staining of these HNSCC cells showed PP-2A can co-localize with microtubules. That the PP-2A influences motility was shown by the increase in HNSCC cell migration through laminin and vitronectin when PP-2A was selectively inhibited with low dose okadaic acid, and by the reduction in invasion through these same matrix components by elevators of PP-2A activity. Motility of HNSCC cells through collagen I or fibronectin was not modulated by PP-2A. The reduction in HNSCC migration through vitronectin or laminin that resulted from treatment with PP-2A elevators was associated with an increase in cellular adhesiveness to these same ECM components. These studies show the association of PP-2A with the cellular cytoskeleton and its role in restricting the invasiveness of tumor cells through select extracellular matrix components.
Meisinger
J
J
Department of Research Services, Hines V.A. Hospital, IL 60141, USA.
Patel
S
S
Vellody
K
K
Bergstrom
R
R
Benefield
J
J
Lozano
Y
Y
Young
M R
MR
D002117:Calcitriol / Q000494:pharmacology; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000556:secondary; D002518:Ceramides / Q000494:pharmacology; D006258:Head and Neck Neoplasms / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D008870:Microtubules / Q000378:metabolism*; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D019319:Okadaic Acid / Q000494:pharmacology; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D054648:Protein Phosphatase 2; D014407:Tumor Cells, Cultured / Q000187:drug effects
D002518:Ceramides; D009363:Neoplasm Proteins; D019319:Okadaic Acid; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2; D002117:Calcitriol