Nanostructured Biomaterials in Tumor Tissue Engineering: Regenerative Medicine and Immunotherapies

The evaluation of nanostructured biomaterials and medicines is associated with 2D cultures that provide insight into the biological mechanisms at the molecular level, while critical aspects of the tumor microenvironment (TME) are provided by the study of animal xenograft models. More realistic models that can histologically reproduce human tumors are provided by tissue engineering methodologies of co-culturing cells of varied phenotypes, to provide 3D tumor spheroids that recapitulate the dynamic TME in 3D matrices. The novel approaches of 3D tumor models are combined with tumor tissue engineering (TTE) scaffolds including hydrogels, bioprinted materials, decellularized tissues, fibrous and nanostructured matrices. This review focuses on the use of nanostructured materials in cancer therapy and regeneration, and the development of realistic models for studying TME molecular and immune characteristics. Tissue regeneration is an important aspect of TTE scaffolds for restoring the normal function of the tissues, while providing cancer treatment. Thus, this article reports recent advancements on the development of 3D TTE models for antitumor drug screening, studying of tumor metastasis, and tissue regeneration. Also, this review identifies the great opportunities of 3D TTE scaffolds in the evaluation of the immunological mechanisms and processes involved in the application of immunotherapies.