Enhanced microtubular stability correlates with lower proliferation and cell motility in stable FTC-133 overexpressing the cytoplasmic domain of epidermal growth factor (proEGFcyt)

• Published in: Experimental and Clinical Endocrinology & Diabetes
• Main Authors: Pyka, J, Glogowska, A, Hoang-Vu, C, Klonisch, T
• Format: Conference Proceeding
• Language: English
• Published: 21.03.2005
• ISSN: 0947-7349; 1439-3646
• DOI: 10.1055/s-2005-863028

The membrane-bound proEGF acts as a functional ligand in a juxtacrine interaction with the EGF receptor on neighbouring cells. Strong expression of proEGF and a novel cytoplasmic proEGF splice variant occures in dedifferentiated thyroid carcinoma cells. To determine the function of the cytoplasmic domain of proEGF (proEGFcyt) in human thyroid, we generated stable FTC-133 human thyroid carcinoma cell transfectants. Overexpression of proEGFcyt in those stable FTC-133 transfectants lead to increased microtubular stability, enhanced production of the microtubule associated proteins MAP1b and MAP2c and decreased expression of the histone deacetylase HDAC6, which has previously been identified to act as a tubulin deacetylase. The cytoskeletal changes in stable FTC-133-proEGFcyt transfectants correlated with increased tubulin acetylation, decreased rates in tumor cell proliferation and cell motility. Furthermore we provide evidence that one of the exons encoding for the cytoplasmic domain of proEGF may be involved in eliciting the phenotypical changes observed in these stable FTC-133 transfectants. Supported by the Deutsche Krebshilfe.