ABSTRACT
The development of efficient molecular imaging probes with high specificity, high sensitivity, and low toxicity is the core in promoting the development of cancer molecular imaging technology. Natural expressed purified protein-based nanocage with self-assembling ability to form intrinsically cavity structure has been widely used to prepare various molecular imaging probes of cancer for its ideal physical properties, excellent biological compatibility, exceptional biodegradability as well as diverse engineering strategies. This paper focuses on the research progress of natural protein-based nanocage from the following aspects: various types of protein-based nanocages of different origins and compositions, cargos loading mechanisms, functionalization strategies, and their recent advances in cancer molecular imaging.