Coordinate Expression of Galectin-3 and Caveolin-1 in Thyroid Cancer.
Journal - The Journal of pathology
Galectin-3 (Gal-3) is the single most accurate marker for diagnosis of differentiated thyroid cancer (DTC). Gal-3 overrides the tumor suppressor activity of caveolin-1 (Cav1) and functions in concert with Cav1 to promote focal adhesion turnover and tumor cell migration and invasion. To study their coordinate role in progression of a human cancer, we investigated expression of Gal-3 and Cav1 in specimens of human benign thyroid lesions, DTC and anaplastic thyroid cancer (ATC). Gal-3 and Cav1 expression is significantly associated with DTC and ATC, but not benign nodules. Essentially all Cav1-positive DTC cancers express Gal-3 supporting the synergistic activity of these two proteins in DTC progression. Similarly, coordinate elevated Gal-3/Cav1 expression was observed in three DTC derived cell lines (papillary TCP1 and KTC1 and follicular FTC133) and but only one (ACT1) of five ATC derived cell lines. Using siRNA knockdown, Gal-3 and Cav1 were shown to be required for RhoA GTPase activation, stabilization of focal adhesion kinase (FAK), a measure of focal adhesion signaling and turnover, and increased migration of the DTC cell lines studied but not the ATC cell lines, including ACT1 that expresses elevated levels of Gal-3 and Cav1. Co-expression of Gal-3 and Cav1 in the T238 anaplastic cell line stabilized FAK-GFP in focal adhesions. Gal-3 and Cav1 therefore function synergistically to promote focal adhesion signaling, migration and progression of DTC. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
RNA purification from tumor cell protrusions using porous polycarbonate filters.
Journal - Methods in molecular biology (Clifton, N.J.) (United States )
Actin-rich cellular protrusions or pseudopodia form via local actin filament polymerization and branching and represent a variety of polarized cellular domains including lamellipodia, filipodia, and neuronal growth cones. RNA localization and local protein translation in these domains are important for various cellular processes. RNA transport and local synthesis have been implicated in cell migration and tumor cell metastasis as well as in neuronal plasticity in neurons. Characterization of the mRNAs present in these domains is key to understanding the functional role of mRNA translocation and local protein translation in cellular processes. We describe here a method to segregate pseudopodia of metastatic cancer cells from the cell body using porous polycarbonate filters. This approach enables the purification and identification of RNAs and proteins in these protrusive cellular domains.
|ISSN : ||1940-6029|
|Mesh Heading : ||Blotting, Western Cell Line, Tumor Electrophoresis, Polyacrylamide Gel Filtration Humans Microscopy, Confocal Neoplasms Polycarboxylate Cement Porosity Proteins Pseudopodia RNA, Neoplasm isolation & purification|
|Mesh Heading Relevant : ||methods genetics pathology chemistry genetics isolation & purification|