Described herein are nanoparticle conjugates that demonstrate enhanced penetration of tumor tissue (e.g., brain tumor tissue) and diffusion within the tumor interstitium, e.g., for treatment of cancer. Further described are methods of targeting tumor-associated macrophages, microglia, and/or other cells in a tumor microenvironment using such nanoparticle conjugates. Moreover, diagnostic, therapeutic, and theranostic (diagnostic and therapeutic) platforms featuring such nanoparticle conjugates are described for treating targets in both the tumor and surrounding microenvironment, thereby enhancing efficacy of cancer treatment. Use of the nanoparticle conjugates described herein with other conventional therapies, including chemotherapy, radiotherapy, immunotherapy, and the like, is also envisaged.
