Tumor-associated Endo180 requires stromal-derived LOX to promote metastatic prostate cancer cell migration on human ECM surfaces.

Matthew P Caley,Julian H Gronau,Justin Sturge,Neel Shah,Helen King,Jonathan Waxman,Kai Wang,Mercedes Rodriguez-Teja

doi:10.1007/s10585-015-9765-7

Abstract

The diverse composition and structure of extracellular matrix (ECM) interfaces encountered by tumor cells at secondary tissue sites can influence metastatic progression. Extensive in vitro and in vivo data has confirmed that metastasizing tumor cells can adopt different migratory modes in response to their microenvironment. Here we present a model that uses human stromal cell-derived matrices to demonstrate that plasticity in tumor cell movement is controlled by the tumor-associated collagen receptor Endo180 (CD280, CLEC13E, KIAA0709, MRC2, TEM9, uPARAP) and the crosslinking of collagen fibers by stromal-derived lysyl oxidase (LOX). Human osteoblast-derived and fibroblast-derived ECM supported a rounded ‘amoeboid-like’ mode of cell migration and enhanced Endo180 expression in three prostate cancer cell lines (PC3, VCaP, DU145). Genetic silencing of Endo180 reverted PC3 cells from their rounded mode of migration towards a bipolar ‘mesenchymal-like’ mode of migration and blocked their translocation on human fibroblast-derived and osteoblast-derived matrices. The concomitant decrease in PC3 cell migration and increase in Endo180 expression induced by stromal LOX inhibition indicates that the Endo180-dependent rounded mode of prostate cancer cell migration requires ECM crosslinking. In conclusion, this study introduces a realistic in vitro model for the study of metastatic prostate cancer cell plasticity and pinpoints the cooperation between tumor-associated Endo180 and the stiff microenvironment imposed by stromal-derived LOX as a potential target for limiting metastatic progression in prostate cancer.Electronic supplementary materialThe online version of this article (doi:10.1007/s10585-015-9765-7) contains supplementary material, which is available to authorized users.

Highlights

Metastatic bone disease (MBD) affects approximately 1 million advanced cancer patients per annum in the EU, USA and Japan; and estimates suggest that approximately one fifth of MBD cases result from advanced prostate cancer [1]
Image analysis revealed that inhibition of collagen crosslinking with the lysyl oxidase (LOX) inhibitor BAPN did not affect the total levels of type I collagen deposition by human osteoblasts (Fig. 1c) or HCA2 fibroblasts (Fig. 1d) but induced a significant increase in the curvature ratio of the collagen fibers in both types of matrices (Fig. 1e, f)
These results confirm that human osteoblastderived extracellular matrix (ECM) and human fibroblast-derived ECM both require LOX to maintain their organized structure, providing two physiologically relevant substrata for studying how tumor-associated Endo180 modulates the plasticity of prostate cancer cell migration in the presence and absence of LOX-dependent collagen crosslinking

Summary

Introduction

Metastatic bone disease (MBD) affects approximately 1 million advanced cancer patients per annum in the EU, USA and Japan; and estimates suggest that approximately one fifth of MBD cases result from advanced prostate cancer [1]. In vitro experimental systems used to study putative metastatic targets tend to overlook the precise composition, organization and bioactivity of human bone and visceral tissues. Human fibroblast-derived ECM has been used to develop more realistic in vitro models of human cancer localized in visceral tissue in which its influence on therapeutic strategies can be considered [5, 6]. Tumor cells can switch back-andforth between different modes of migration in response to external and/or internal cues. This type of morphological plasticity is a feature of the epithelial-to-mesenchymal, mesenchymal-to-amoeboid and collective-to-amoeboid transitions that occur during tumor progression [9, 10]. Instead rounded cell migration is driven by the spatial localization of integrins and cytoskeletal regulators at the posterior plasma membrane [14, 15] and generation of RhoA and Rho kinase associated protein kinase (ROCK)-based actinomyosin contractile signals [16]

Methods

Results

Conclusion