Studying Normal Tissue Radiation Effects using Extracellular Matrix Hydrogels

Abstract

Radiation is a therapy for patients with triple negative breast cancer. The effect of radiation on the extracellular matrix (ECM) of healthy breast tissue and its role in local recurrence at the primary tumor site are unknown. Here we present a method for the decellularization, lyophilization, and fabrication of ECM hydrogels derived from murine mammary fat pads. Results are presented on the effectiveness of the decellularization process, and rheological parameters were assessed. GFP- and luciferase-labeled breast cancer cells encapsulated in the hydrogels demonstrated an increase in proliferation in irradiated hydrogels. Finally, phalloidin conjugate staining was employed to visualize cytoskeleton organization of encapsulated tumor cells. Our goal is to present a method for fabricating hydrogels for in vitro study that mimic the in vivo breast tissue environment and its response to radiation in order to study tumor cell behavior.

Emerging Biomimetic Materials for Studying Tumor and Immune Cell Behavior

“…For example, murine mammary fat pads were decellularized and exposed to radiation ex vivo. 3 Using these dECM hydrogels allowed for studying the effect of radiation on breast cancer proliferation and invasion in the context of recurrence after therapy. Wolf and coworkers also showed that the ECM derived from urinary bladder can support 3T3 fibroblast growth and proliferation.…”

“…46 An important application of biomimetic materials is to study the behavior of cancer cells treated with novel therapies. 3 One approach is local cancer immunotherapy, a treatment intended to stimulate the immune system of cancer patients commonly achieved through Tcell infusion, vaccines, or antibodies to inhibit proteins produced by cancer cells using macroscale bio-materials. 29,83 The principal advantage of local immunotherapy is specific immunomodulation at the tumor site, which prevents systemic toxicity.…”

“…The process of deriving decellularized ECM from various organs for hydrogel formation. 3,41,76,78,116…”

The Effects of Ionising and Non-Ionising Electromagnetic Radiation on Extracellular Matrix Proteins

“…Murine mammary fat pads decellularised and made into hydrogels. [206] Increased proliferation for murine TNBC reseeded on irradiated hydrogel.…”

“…Decellularised cultures ( Table 3 ) involve taking tissue samples from living organisms and removing the cells from the tissue, leaving behind the ECM scaffold and proteins for cell culture applications [ 206 , 207 ]. There is still little evidence of UVR affecting large scale mechanical properties of such ECM scaffolds, although localised changes in molecular structure may be occurring [ 208 ].…”