Original Article
Copyright ©2010 Baishideng. All rights reserved.
World J Gastroenterol. Jun 14, 2010; 16(22): 2743-2753
Published online Jun 14, 2010. doi: 10.3748/wjg.v16.i22.2743
Unlocking the ultrastructure of colorectal cancer cells in vitro using selective staining
Joanna M Biazik, Kristina A Jahn, Yingying Su, Ya-Na Wu, Filip Braet
Joanna M Biazik, Kristina A Jahn, Yingying Su, Ya-Na Wu, Filip Braet, Australian Key Centre for Microscopy and Microanalysis, Madsen Building F09, The University of Sydney, NSW 2006, Australia
Author contributions: Biazik JM prepared the manuscript for publication, conducted the selective staining and sectioning for transmission electron microscopy, data analysis, and data interpretation for the three cell lines; Jahn KA, Su Y and Wu YN carried out cell culture on the three cell lines; Braet F assisted in data interpretation and manuscript preparation.
Supported by The Australian Research Council for funding some of the research reported herein through Linkage Infrastructure, Equipment and Facilities grants, No. LE0775598 and the ARC/NHMRC FABLS Research Network, No. RN0460002
Correspondence to: Dr. Joanna M Biazik, Australian Key Centre for Microscopy and Microanalysis, Madsen Building F09, The University of Sydney, NSW 2006, Australia. j.biazik@usyd.edu.au
Telephone: +61-2-93515220 Fax: +61-2-93517682
Received: December 11, 2009
Revised: January 20, 2010
Accepted: January 27, 2010
Published online: June 14, 2010
Abstract

AIM: To characterise differences between three widely used colorectal cancer cell lines using ultrastructural selective staining for glycogen to determine variation in metastatic properties.

METHODS: Transmission electron microscopy was used in this investigation to help identify intracellular structures and morphological features which are precursors of tumor invasion. In addition to morphological markers, we used selective staining of glycogen as a marker for neoplastic cellular proliferation and determined whether levels of glycogen change between the three different cell lines.

RESULTS: Ultrastructural analysis revealed morphological differences between the cell lines, as well as differentiation into two sub-populations within each cell line. Caco-2 cells contained large glycogen deposits as well as showing the most obvious morphological changes between the two sub-populations. SW480 cells also contained large glycogen stores as well as deep cellular protrusions when grown on porous filter membranes. HT-29 cells had trace amounts of glycogen stores with few cellular projections into the filter pores and no tight junction formation.

CONCLUSION: Morphology indicative of metastatic properties coincided with larger glycogen deposits, providing strong evidence for the use of selective staining to determine the neoplastic properties of cells.

Keywords: Cancer; Colorectal; Electron microscopy; Glycogen; Potassium ferrocyanide