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Title: Ski protein levels increase during in vitro progression of HPV16-immortalized human keratinocytes and in cervical cancer

Abstract

We compared the levels of the Ski oncoprotein, an inhibitor of transforming growth factor-beta (TGF-β) signaling, in normal human keratinocytes (HKc), HPV16 immortalized HKc (HKc/HPV16), and differentiation resistant HKc/HPV16 (HKc/DR) in the absence and presence of TGF-β. Steady-state Ski protein levels increased in HKc/HPV16 and even further in HKc/DR, compared to HKc. TGF-β treatment of HKc, HKc/HPV16, and HKc/DR dramatically decreased Ski. TGF-β-induced Ski degradation was delayed in HKc/DR. Ski and phospho-Ski protein levels are cell cycle dependent with maximal Ski expression and localization to centrosomes and mitotic spindles during G2/M. ShRNA knock down of Ski in HKc/DR inhibited cell proliferation. More intense nuclear and cytoplasmic Ski staining and altered Ski localization were found in cervical cancer samples compared to adjacent normal tissue in a cervical cancer tissue array. Overall, these studies demonstrate altered Ski protein levels, degradation and localization in HPV16-transformed human keratinocytes and in cervical cancer. - Highlights: • Ski oncoprotein levels increase during progression of HPV16-transformed cells. • Ski and phospho-Ski protein levels are cell cycle dependent. • Ski knock-down in HPV16-transformed keratinocytes inhibited cell proliferation. • Cervical cancer samples overexpress Ski.

Authors:
;  [1];  [2]
  1. Department of Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC (United States)
  2. Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC (United States)
Publication Date:
OSTI Identifier:
22436643
Resource Type:
Journal Article
Resource Relation:
Journal Name: Virology; Journal Volume: 444; Journal Issue: 1-2; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CELL CYCLE; CELL PROLIFERATION; COMPARATIVE EVALUATIONS; GROWTH FACTORS; IN VITRO; NEOPLASMS

Citation Formats

Chen, Yi, Pirisi, Lucia, and Creek, Kim E., E-mail: creekk@sccp.sc.edu. Ski protein levels increase during in vitro progression of HPV16-immortalized human keratinocytes and in cervical cancer. United States: N. p., 2013. Web. doi:10.1016/J.VIROL.2013.05.039.
Chen, Yi, Pirisi, Lucia, & Creek, Kim E., E-mail: creekk@sccp.sc.edu. Ski protein levels increase during in vitro progression of HPV16-immortalized human keratinocytes and in cervical cancer. United States. doi:10.1016/J.VIROL.2013.05.039.
Chen, Yi, Pirisi, Lucia, and Creek, Kim E., E-mail: creekk@sccp.sc.edu. 2013. "Ski protein levels increase during in vitro progression of HPV16-immortalized human keratinocytes and in cervical cancer". United States. doi:10.1016/J.VIROL.2013.05.039.
@article{osti_22436643,
title = {Ski protein levels increase during in vitro progression of HPV16-immortalized human keratinocytes and in cervical cancer},
author = {Chen, Yi and Pirisi, Lucia and Creek, Kim E., E-mail: creekk@sccp.sc.edu},
abstractNote = {We compared the levels of the Ski oncoprotein, an inhibitor of transforming growth factor-beta (TGF-β) signaling, in normal human keratinocytes (HKc), HPV16 immortalized HKc (HKc/HPV16), and differentiation resistant HKc/HPV16 (HKc/DR) in the absence and presence of TGF-β. Steady-state Ski protein levels increased in HKc/HPV16 and even further in HKc/DR, compared to HKc. TGF-β treatment of HKc, HKc/HPV16, and HKc/DR dramatically decreased Ski. TGF-β-induced Ski degradation was delayed in HKc/DR. Ski and phospho-Ski protein levels are cell cycle dependent with maximal Ski expression and localization to centrosomes and mitotic spindles during G2/M. ShRNA knock down of Ski in HKc/DR inhibited cell proliferation. More intense nuclear and cytoplasmic Ski staining and altered Ski localization were found in cervical cancer samples compared to adjacent normal tissue in a cervical cancer tissue array. Overall, these studies demonstrate altered Ski protein levels, degradation and localization in HPV16-transformed human keratinocytes and in cervical cancer. - Highlights: • Ski oncoprotein levels increase during progression of HPV16-transformed cells. • Ski and phospho-Ski protein levels are cell cycle dependent. • Ski knock-down in HPV16-transformed keratinocytes inhibited cell proliferation. • Cervical cancer samples overexpress Ski.},
doi = {10.1016/J.VIROL.2013.05.039},
journal = {Virology},
number = 1-2,
volume = 444,
place = {United States},
year = 2013,
month = 9
}
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