Three-dimensional tumor model mimics stromal - breast cancer cells signaling

Abstract

Tumor stroma is a major contributor to the biological aggressiveness of cancer cells. Cancer cells induce activation of normal fibroblasts to carcinoma-associated fibroblasts (CAFs), which promote survival, proliferation, metastasis, and drug resistance of cancer cells. A better understanding of these interactions could lead to new, targeted therapies for cancers with limited treatment options, such as triple negative breast cancer (TNBC). To overcome limitations of standard monolayer cell cultures and xenograft models that lack tumor complexity and/or human stroma, we have developed a high throughput tumor spheroid technology utilizing a polymeric aqueous two-phase system to conveniently model interactions of CAFs and TNBC cells and quantify effects on signaling and drug resistance of cancer cells. We focused on signaling by chemokine CXCL12, a hallmark molecule secreted by CAFs, and receptor CXCR4, a driver of tumor progression and metastasis in TNBC. Using three-dimensional stromal-TNBC cells cultures, we demonstrate that CXCL12 – CXCR4 signaling significantly increases growth of TNBC cells and drug resistance through activation of mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) pathways. Despite resistance to standard chemotherapy, upregulation of MAPK and PI3K signaling sensitizes TNBC cells in co-culture spheroids to specific inhibitors of these kinase pathways. Furthermore, disrupting CXCL12 – CXCR4 signaling diminishes drug resistance of TNBC cells in co-culture spheroid models. This work illustrates the capability to identify mechanisms of drug resistance and overcome them using our engineered model of tumor-stromal interactions.

Cell‐Inspired All‐Aqueous Microfluidics: From Intracellular Liquid–Liquid Phase Separation toward Advanced Biomaterials

“… The patterned tumor spheroids partially addressed challenges in the heterogeneity of spheroid culture in vitro, which is therefore used as promising platforms for executing high‐throughput anticancer compounds screening. The ability to scale‐up 3D spheroid culture in microfluidic devices offers new opportunity for fast testing of multiple anticancer drugs and analyze their half‐maximum (IC 50 ) and maximum ( E max ) inhibitory concentrations, which facilitates the multiparametric analysis of cellular responses to drug compounds and identify novel chemical probes with chemotherapeutic benefits, as demonstrated in Figure 26e …”

Three‐dimensional culture models to study drug resistance in breast cancer

“…These cytokines are known to promote chemoresistance (Mao et al, 2015; Su et al, 2018). Another coculture model used to study chemoresistance to paclitaxel (PTX), is an aqueous two‐phase system (ATPS) engineered by robotically dispensed MDA‐MB‐231 cells with matched donor human mammary fibroblasts and CAFs (1:2 TNBC:stromal) in a DEX‐phase nanodrop (Ham et al, 2018). The incorporation of CAFs was important as this has been previously reported to contribute to MDA‐MB‐231 chemoresistance in 2D (Amornsupak et al, 2014; Goliwas et al, 2017).…”

“…The incorporation of CAFs was important as this has been previously reported to contribute to MDA‐MB‐231 chemoresistance in 2D (Amornsupak et al, 2014; Goliwas et al, 2017). ATPS study revealed that the signaling between the CXCL12 cytokine secreted by CAFs and the associated receptor CXCR‐4 activated the MAPK/PI3K pathway driving proliferation and drug resistance (Ham et al, 2018). In another coculture study, Brancato et al (2018) compared the applicability of the basic spheroid model to a 3D microtissue (3D‐μTP) scaffold in which the cells spread throughout a porous gelatin microbead to test the efficacy of DOX on MCF7 breast cancer cells with and without incorporation of CAFs (Brancato et al, 2018).…”

Optical clearing methods: An overview of the techniques used for the imaging of 3D spheroids

“…Thus, 3D cell cultures, such as spheroids, have received great attention from the research community, as these in vitro models can represent more accurately the different properties of human tissues, such as liver (Yoon, Lee, Lee, & Lee, 2015), thyroid *Elisabete C. Costa and Daniel N. Silva contributed equally to this work. (Cirello et al, 2017), cartilage (Jukes et al, 2008), pancreatic tissue (Lumelsky et al, 2001), cardiac muscle (Kehat et al, 2001) or of solid tumors (e.g., breast, colon, pancreas, prostate, ovary, among others (Eiraku et al, 2008;Eiraku et al, 2011;Ham et al, 2018;Ham, Joshi, Luker, & Tavana, 2016;Hamilton, 1998;Khawar et al, 2018;Lazzari et al, 2018;Suga et al, 2011)). Spheroids are microtissues with a diameter within hundreds of micrometers to few millimeters that present a spatial architecture, cellular organization, cell-cell, and cell-extracellular matrix interactions quite similar to those found in the human tissues (as reviewed in detail elsewhere (Costa et al, 2016;Duval et al, 2017)).…”