Biofabrication using well-matched cell/materials systems provides unprecedented opportunities for dealing with human health issues where disease or injury overtake the body’s native regenerative abilities. Such opportunities can be enhanced through the development of biomaterials with cues that appropriately influence embedded cells into forming functional tissues and organs. In this context, biomaterials’ reliance on rigid biofabrication techniques needs to support the incorporation of a hierarchical mimicry of local and bulk biological cues that mimic the key functional components of native extracellular matrix. Advances in synthetic self-assembling peptide biomaterials promise to produce reproducible mimics of tissue-specific structures and may go some way in overcoming batch inconsistency issues of naturally sourced materials. Recent work in this area has demonstrated biofabrication with self-assembling peptide biomaterials with unique biofabrication technologies to support structural fidelity upon 3D patterning. The use of synthetic self-assembling peptide biomaterials is a growing field that has demonstrated applicability in dermal, intestinal, muscle, cancer and stem cell tissue engineering.

A significant challenge to current cancer drug treatment is mode of delivery, both in terms of efficacy and off-target toxicity to healthy tissues. To overcome this, drug localisation using a range of biocompatible carriers is currently in use or under investigation. One class of these biomaterial carriers that offers a unique prospect for use as drug delivery vectors to tumour sites is hydrogels formed by small molecules. In particular, tissue mimetic self-assembling molecular hydrogels can function either as injectable precursors that gelate in response to tumour-specific markers, or as implants in conjunction with surgical resection or tumour debulking. Their inherent biocompatibility, tuneable properties, and capacity to flow and gelate in situ allow them to effectively transport, hold and release therapeutic molecules in a spatially and temporally controlled manner. This has been shown in a number of in vitro and in vivo studies, where they improve anti-cancer efficacy while reducing non-specific toxicity. However, further investigation is required to optimise these systems toward both the drug and the target tissue, to provide sophisticated temporal control over the drug presentation, and to determine the most effective drug–material combinations for specific cancer types and locations.

Metastatic tumours are complex ecosystems; a community of multiple cell types, including cancerous cells, fibroblasts, and immune cells that exist within a supportive and specific microenvironment. The interplay of these cells, together with tissue specific chemical, structural and temporal signals within a three-dimensional (3D) habitat, direct tumour cell behavior, a subtlety that can be easily lost in 2D tissue culture. Here, we investigate a significantly improved tool, consisting of a novel matrix of functionally programmed peptide sequences, self-assembled into a scaffold to enable the growth and the migration of multicellular lung tumour spheroids, as proof-of-concept. This 3D functional model aims to mimic the biological, chemical, and contextual cues of an in vivo tumor more closely than a typically used, unstructured hydrogel, allowing spatial and temporal activity modelling. This approach shows promise as a cancer model, enhancing current understandings of how tumours progress and spread over time within their microenvironment.

All data sets corresponding to figure published in Advanced Functional Materials "Tissue programmed hydrogels functionalized with GDNF improve human neural grafts in Parkinson’s Disease".