Dynamic and influential interaction of cancer cells with normal epithelial cells in 3D culture.

Laura P Ivers,Dimitri Scholz,Katarzyna Welzel,Brendan Cummings,Darran O’Connor,Rut Klinger,Sayaka Saitoh,Yasuyuki Fujita,Funke Owolabi,Nobue Itasaki

doi:10.1186/s12935-014-0108-6

Laura P Ivers, Dimitri Scholz + Show 8 more

Open Access

https://doi.org/10.1186/s12935-014-0108-6

Copy DOI

Abstract

BackgroundThe cancer microenvironment has a strong impact on the growth and dynamics of cancer cells. Conventional 2D culture systems, however, do not reflect in vivo conditions, impeding detailed studies of cancer cell dynamics. This work aims to establish a method to reveal the interaction of cancer and normal epithelial cells using 3D time-lapse.MethodsGFP-labelled breast cancer cells, MDA-MB-231, were co-cultured with mCherry-labelled non-cancerous epithelial cells, MDCK, in a gel matrix. In the 3D culture, the epithelial cells establish a spherical morphology (epithelial sphere) thus providing cancer cells with accessibility to the basal surface of epithelia, similar to the in vivo condition. Cell movement was monitored using time-lapse analyses. Ultrastructural, immunocytochemical and protein expression analyses were also performed following the time-lapse study.ResultsIn contrast to the 2D culture system, whereby most MDA-MB-231 cells exhibit spindle-shaped morphology as single cells, in the 3D culture the MDA-MB-231 cells were found to be single cells or else formed aggregates, both of which were motile. The single MDA-MB-231 cells exhibited both round and spindle shapes, with dynamic changes from one shape to the other, visible within a matter of hours. When co-cultured with epithelial cells, the MDA-MB-231 cells displayed a strong attraction to the epithelial spheres, and proceeded to surround and engulf the epithelial cell mass. The surrounded epithelial cells were eventually destroyed, becoming debris, and were taken into the MDA-MB-231 cells. However, when there was a relatively large population of normal epithelial cells, the MDA-MB-231 cells did not engulf the epithelial spheres effectively, despite repeated contacts. MDA-MB-231 cells co-cultured with a large number of normal epithelial cells showed reduced expression of monocarboxylate transporter-1, suggesting a change in the cell metabolism. A decreased level of gelatin-digesting ability as well as reduced production of matrix metaroproteinase-2 was also observed.ConclusionsThis culture method is a powerful technique to investigate cancer cell dynamics and cellular changes in response to the microenvironment. The method can be useful for various aspects such as; different combinations of cancer and non-cancer cell types, addressing the organ-specific affinity of cancer cells to host cells, and monitoring the cellular response to anti-cancer drugs.Electronic supplementary materialThe online version of this article (doi:10.1186/s12935-014-0108-6) contains supplementary material, which is available to authorized users.

Highlights

The cancer microenvironment has a strong impact on the growth and dynamics of cancer cells
Morphological diversity and dynamics of MDA-MB-231 cells in 3D The breast cancer cells MDA-MB-231 exhibit a spindleshaped morphology when cultured in 2D [17] (Figure 1A)
In 3D culture MDA-MB-231 exhibit a wide variety of cell morphologies which are not normally seen in 2D culture

Summary

Introduction

The cancer microenvironment has a strong impact on the growth and dynamics of cancer cells. When a single epithelial cell is transformed by an oncogene and is surrounded by normal epithelial cells, the transformed cell is, in many cases, apically extruded and eliminated from the epithelium [3,4] In another example, normal breast epithelial cells or their conditioned media attenuate the growth of co-cultured breast cancer cells [5,6]. In mammary ducts in vivo, myoepithelial cells surround luminal cells on their basal side and secrete anti-invasive and anti-angiogenic factors [9] These examples represent the preventive effect of the normal cellular microenvironment on the early stages of tumour growth and may explain why the chance of a small number of tumour cells successfully establishing a colony or forming secondary tumours in a new location is extremely low [1,10]

Objectives

Methods

Results

Discussion

Conclusion