Loss of miR-200 family in 5-fluorouracil resistant colon cancer drives lymphendothelial invasiveness in vitro.

Abstract

Invasive colorectal cancer is associated with poor prognosis requiring treatment with systemic chemotherapies usually including 5-fluorouracil. A consequence of prolonged treatment is the acquisition of resistance eventually resulting in the recurrence of highly metastatic cancer cells. To address the relationship between drug resistance and increased lymphatic metastatic potential, we used a 3D co-culture model of colon tumour cell spheroids of parent CCL227 cells and subclones with gradually increasing resistance against 5-fluorouracil. From each investigated cell line, homogeneous tumour spheroids were generated in the presence of methylcellulose yielding emboli of ∼700 µm diameter. When invasive, tumour spheroids disrupt the continuous lymphendothelial cell (LEC) layer and generate a 'circular chemorepellent-induced defect' (CCID), reminiscent of the entry gates through which tumour emboli intravasate lymphatic vasculature. Here we provide evidence that increasingly chemoresistant colon cancer spheroids were strongly associated with enhanced intravasative properties. In naïve CCL227 spheroids, miR-200 family members were released into exosomes thereby repressing the epithelial to mesenchymal transition-regulating transcription factors ZEB1 and SLUG in LEC. As a consequence of attenuated plasticity and migration of LEC, CCID formation was impaired. Loss of exosomal transferred miR-200c in resistant colon cells rendered LEC more susceptible to pro-migratory signals that were generated and directly transmitted by colon cancer spheroids. This observation indicates a common molecular axis in colon cancer and LEC where miR-200 family members act as regulators of ZEB proteins. The data support the notion that horizontal miR-200 signalling prevents the permeation of cells into adjacent epithelia and contributes to organ integrity.

• Authors: Daniel Senfter, Silvio Holzner, Maria Kalipciyan, Anna Staribacher, Angelika Walzl, Nicole Huttary, Sigurd Krieger, Stefan Brenner, Walter Jäger, Georg Krupitza, Helmut Dolznig, Robert M Mader
• Journal: Human molecular genetics (Hum Mol Genet) Vol. 24 Issue 13 Pg. 3689-98 (Jul 01 2015) ISSN: 1460-2083 [Electronic] England
• PMID: 25832648 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected].

Chemical References

• Homeodomain Proteins
• MIRN141 microRNA, human
• MIRN200 microRNA, human
• MicroRNAs
• SNAI1 protein, human
• Snail Family Transcription Factors
• Transcription Factors
• ZEB1 protein, human
• Zinc Finger E-box-Binding Homeobox 1
• Fluorouracil

Topics

• Cell Line, Tumor
• Colonic Neoplasms (drug therapy, genetics, metabolism, pathology)
• Drug Resistance, Neoplasm
• Endothelial Cells (drug effects, metabolism)
• Fluorouracil (pharmacology)
• Homeodomain Proteins (genetics, metabolism)
• Humans
• Lymphatic Metastasis
• MicroRNAs (genetics, metabolism)
• Multigene Family
• Neoplasm Invasiveness
• Snail Family Transcription Factors
• Spheroids, Cellular (drug effects, metabolism)
• Transcription Factors (genetics, metabolism)
• Tumor Cells, Cultured
• Zinc Finger E-box-Binding Homeobox 1